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2010-Successful aging foucus on congnitive and emotion-annurev[1].clinpsy.121208.131449

RE V I E WSI NAD V ANC ESuccessful Aging:Focus on Cognitive and Emotional HealthColin Depp,Ipsit V .Vahia,and Dilip JesteSam and Rose Stein Institute for Research on Aging,Department of Psychiatry,University of California,San Diego,La Jolla,California 92093;email:cdepp@Annu.Rev.Clin.Psychol.2010.6:19.1–19.24The Annual Review of Clinical Psychology is online at This article’s doi:10.1146/annurev.clinpsy.121208.131449Copyright c2010by Annual Reviews.All rights reserved1548-5943/10/0427-0001$20.00Key Wordsolder adult,elderly,cognitive aging,healthy aging,resilience,stressAbstractWe review the deﬁnitions,predictors,and biobehavioral determinants of successful aging,as well as the evidence for and mechanisms of under-lying selected interventions to enhance cognitive and emotional health in older adults.Deﬁning successful aging has proven difﬁcult,with dis-crepancies seen among biomedical,psychological,and lay perspectives.Although consensus is lacking,a number of studies have examined the genetic,lifestyle,and social determinants of operationalized determi-nants of successful aging;qualitative examinations of the meaning of the construct have also been conducted.The determinants coincide with fundamental aspects of aging.Recent clinical trials suggest that caloric restriction,physical activity,cognitive intervention,stress reduction,and social programs may enhance cognitive and emotional health in older people.19.1A n n u . R e v . C l i n . P s y c h o l . 2010.6. D o w n l o a d e d f r o m a r j o u r n a l s .a n n u a l r e v i e w s .o r g b y C h i n e s e A c a d e m y o f S c i e n c e s - I n s t i t u t e o f P s y c h o l o g y o n 01/26/10. F o r p e r s o n a l u s e o n l y .ContentsINTRODUCTION..................19.2DEFINING SUCCESSFULAGING...........................19.3History of Successful Agingas a Research Focus.............19.3Quantitative Studies of UsingDeﬁnitions of Successful Aging..19.4Qualitative Studies Assessing Lay Perspectives onSuccessful Aging................19.4Indices of BiologicalAge/Intermediate Phenotypes ...19.5Summary of Deﬁnitions ofSuccessful Aging................19.6Increasing the Focus on Cognitiveand Emotional Aging ...........19.6DETERMINANTS OF COGNITIVEAND EMOTIONAL HEAL TH ...19.7Genetic Determinants..............19.7Basic Biological Determinants......19.8Neurobiological Determinants .....19.9Emotional/PsychologicalDeterminants...................19.10Social/EnvironmentalDeterminants...................19.11Summary of the Determinantsof Successful Aging .............19.12INTERVENTIONS TO PROMOTE SUCCESSFUL COGNITIVEAND EMOTIONAL AGING .....19.12Physical Activity...................19.13Caloric Restriction/DietaryInﬂuences ......................19.14Cognitive Stimulationand T raining....................19.14Social Interventions................19.15Meditation ........................19.16Anti-Aging Interventions...........19.16Summary of Interventions..........19.16CONCLUSION .....................19.17INTRODUCTIONAs of 2008,there were 506million people in the world older than 65years;in 2040,there will be1.4billion (Kinsella &He 2009).In the United States,as the baby boom cohort enters older adulthood,the number of people over 65will rise to 72million (20%of the population)by 2030(Greenberg 2008).There is no precedent to this population change,as older adults will outnumber children younger than age 14for the ﬁrst time in recorded history (Road to Aging 1996).By and large,older people are healthier than their predecessors of just a few genera-tions ago,as observed in Robert Fogel’s Union Army Studies,with mean onset of age-related diseases occurring later in the current cohort of older adults compared to their predecessors (Fogel 2004)and rates of disability declining (Manton 2008).At the same time,there has been a shift in the past 100years in the cause of mortality,from infectious disease to age-related chronic illnesses as the most common causes of death (e.g.,cardiovascular disease,cancer,and stroke).There are some predictions that the gains made in average lifespan may be relin-quished owing to obesity trends and the corre-sponding increases in diabetes (Olshansky et al.2005).These remarkable and rapidly evolving changes to the age distribution of our species and the emergence of age-related diseases as primary determinants of human morbidity and mortality are cause for the claim that aging is the number one public health issue faced by the developed world (Cutler &Mattson 2006).Complementary to efforts to differentiate pathological aging from normal aging,a small body of research has attempted to identify the characteristics,determinants,and interventions that promote successful aging.There is remark-able divergence among researchers and laypeo-ple as to what deﬁnes successful aging and even as to what descriptor to use (e.g.,optimal ag-ing,robust aging,positive aging,healthy aging).Despite the lack of consensus in the construct of successful aging,a number of exciting re-cent ﬁndings have characterized and promoted positive states of health and well-being in older people—particularly in the realm of cognitive and emotional aspects of aging well.In the fol-lowing review,we describe (a )the status of the deﬁnitions and components of successful aging,19.2Depp·V ahia·JesteA n n u . R e v . C l i n . P s y c h o l . 2010.6. D o w n l o a d e d f r o m a r j o u r n a l s .a n n u a l r e v i e w s .o r g b y C h i n e s e A c a d e m y o f S c i e n c e s - I n s t i t u t e o f P s y c h o l o g y o n 01/26/10. F o r p e r s o n a l u s e o n l y .(b )hypothetical determinants and mechanisms focusing on cognition and emotion,and (c )evi-dence for the effectiveness of selected interven-tions to promote successful aging.DEFINING SUCCESSFUL AGING History of Successful Aging as a Research FocusThere has long been a dialogue regarding the attainment of healthy aging and longevity that conﬂicts with popular assumptions about ag-ing and decline.In Cicero’s powerful essay Cato Maior De Senectute (44BC),the author refuted prevailing negative stereotypes about aging.Ci-cero systematically enumerated ways in which positive outcomes could be attained in older age,including adaption of life roles (e.g.,ful-ﬁlling advisory roles)and the plasticity of the aging mind (e.g.,the positive effect of mental exercise on memory).However,perhaps the earliest speciﬁc use of the term “successful aging”in the biomedical literature was in 1961,in an editorial in the ﬁrst issue of the Gerontologist .Drawing from the Kansas City Studies of Adult Life (among the ﬁrst longitudinal studies aimed at understand-ing the transition from middle age to older age),Havighurst (1961)described successful aging as “getting a maximum of satisfaction out life,”and called upon the young ﬁeld of gerontology to research and promote successful aging.Subsequent inﬂuential lifespan devel-opmental theories of aging,such as the disengagement theory (Cumming &Henry 1961),activity theory (Lemon et al.1972),and continuity theory (Atchley 1989,Ryff 1982),integrated data from longitudinal research in order to depict the course of normative late-life development,which had been the subject of far less attention relative to efforts to understand development in younger adults.These theories extended earlier life-stage theories,including that of Erikson (1959),in which successful reso-lution of earlier conﬂicts were presumed to lead to better late-life outcomes (e.g.,ego integrity)(Erikson 1959).Lifespan developmentalCompression of morbidity (COM):delay of the onset of disability relative to age of deaththeories pointed toward often divergent developmental trends that could account for positive states of health in older age;for example,disengagement theory described late adulthood in terms of the cultural pressures toward reduced involvement with society.Activity theory pointed toward continued en-gagement and corresponded with the growing number of senior centers.Continuity theory emphasized the general trend for older adults to maintain consistency with earlier life roles and adaptation of activities to sustain such roles.Despite their differences,underlying the above theories is the assumption that longevity,in and of itself,is an inadequate proxy and that maintaining independence or maximizing well-being were more important constructs in deﬁn-ing positive aging.Fries (1980)described the more optimal of goal of striving for compres-sion of morbidity (COM).COM assumes that the lifespan is relatively ﬁnite,and delaying the onset of disability would thus shorten the pro-portion of life during which an individual ex-periences disability.The ideal old age would involve living free of disability until death.Healthy aging would be thus be measured by the number of disability-free years (known as the healthspan)rather than chronological years.In subsequent seminal works,Rowe &Kahn (1987)and Baltes et al.(1990)addressed the concept of successful aging more explicitly,proposing testable models.Rowe &Kahn (1987)eloquently argued that (a )existing re-search had largely failed to delineate success-ful and healthy aging,instead focusing on differentiating pathology from normal aging,and that (b )successful aging is at the other end of the continuum from pathological ag-ing and is a multidimensional and operational-izable construct that deserved its own rigor-ous study.Rowe and Kahn’s theoretical model of successful aging included three compo-nents:(a )freedom from disability and disease,(b )high cognitive and physical functioning,and (c )social engagement (in terms of involve-ment both in social and productive activities).This model was employed in the MacArthur •Successful Aging19.3A n n u . R e v . C l i n . P s y c h o l . 2010.6. D o w n l o a d e d f r o m a r j o u r n a l s .a n n u a l r e v i e w s .o r g b y C h i n e s e A c a d e m y o f S c i e n c e s - I n s t i t u t e o f P s y c h o l o g y o n 01/26/10. F o r p e r s o n a l u s e o n l y .Research Network on Successful Aging,which for nearly a decade followed a cohort of more than 1000older adults meeting an operational-ized deﬁnition based on these criteria (Berkman et al.1993,Rowe &Kahn 1997,Seeman et al.1994).A complementary theory (Baltes &Smith 2003),selection optimization and com-pensation (SOC),approached successful aging from the perspective of lifespan development,focusing on psychological and behavioral pro-cesses involved in adapting to age-related losses and disabilities and maintaining performance on functional tasks.Baltes and colleagues based this model on the the Berlin Aging Study,which followed older adults between ages 70and 100(Baltes &Mayer 1999).Both Rowe and Kahn and the SOC theory were instrumental in sub-sequent research on successful aging.Quantitative Studies of Using Deﬁnitions of Successful AgingSince publication of the Rowe &Kahn (1987)paper,the deﬁnition,prevalence,and predic-tors of successful aging have been the focus of a number of quantitative and qualitative stud-ies (see reviews by Depp &Jeste 2006,Peel et al.2005,and Phelan &Larson 2002).These reviews were aimed at understanding how re-searchers and laypeople interpreted the success-ful aging construct as well which variables best separated successful from unsuccessful groups.In a review of 11studies,Phelan found that seven dimensions of successful aging were used across these studies and noted that deﬁni-tions of successful aging lacked the perspectives of older people themselves.Building on the Phelan review,Depp &Jeste (2006)reviewed 28studies published between 1987and 2006in English language peer-reviewed journals with sample sizes greater than 100.The majority of these publications derived from large epidemi-ological investigations,where the main focus was on disease progression (e.g.,cardiovascular disease).The Depp &Jeste (2006)review identiﬁed 29unique deﬁnitions of successful aging em-ployed in 28studies,and the only componentof successful aging used in more than half of the studies was physical functioning/disability.Fourteen components appeared in more than one study,including cognitive ability,life sat-isfaction,social functioning,and absence of disease.Accordingly,the proportion of indi-viduals categorized as aging successfully var-ied broadly (from 1%to 94%,median 35%)and was negatively associated with the number of components used in the deﬁnitions.Thus,among research deﬁnitions of successful aging,little consensus exists regarding constituent do-mains of successful aging other than physical functioning/disability.In the Depp &Jeste (2006)review,the strongest predictor of membership in the “suc-cessful”category was younger age,deﬁned as close to 60(observed in 13of 15studies).Pre-dictors signiﬁcantly differentiating successful from unsuccessful groups in more than three articles include absence of arthritis,absence of hearing problems,and lower historical/present smoking.Predictors that were less consistent across studies included higher levels of exer-cise or physical activity,higher self-rated health,lower systolic blood pressure,fewer medical conditions,and absence of depression.There was limited evidence for higher income,greater education,marriage,and white ethnicity as pre-dictors.It is not surprising that younger age predicted membership groups dichotomized as successful given that most of the deﬁnitions of successful included physical functioning and disability.Qualitative Studies Assessing Lay Perspectives on Successful AgingA small number of mixed-method and quali-tative studies have examined the construct of successful aging from the perspectives of older adults.von Faber et al.(2001)used a mixed-method approach to study 599adults aged 85and older.Participants were categorized as successfully aging if they met objective cri-teria derived from the Rowe &Kahn (1987)model of successful aging,and a subsample of participants were interviewed regarding their19.4Depp·V ahia·JesteA n n u . R e v . C l i n . P s y c h o l . 2010.6. D o w n l o a d e d f r o m a r j o u r n a l s .a n n u a l r e v i e w s .o r g b y C h i n e s e A c a d e m y o f S c i e n c e s - I n s t i t u t e o f P s y c h o l o g y o n 01/26/10. F o r p e r s o n a l u s e o n l y .deﬁnition of successful aging.In comparison to the quantitative results,qualitative interview data suggested that interviewed older adults were more likely to (a )endorse themselves as aging successfully relative to the proportion that met researcher-deﬁned criteria,and (b )de-pict successful aging in terms of well-being and employ adaptive behaviors to maintain it.In separate studies,Strawbridge et al.(2002)asked older participants in the Alameda County Study to rate whether they were “aging well,”and Montross et al.(2006)employed a single-item (1to 10)subjective rating scale—both studies compared the distribution of subjective ratings of successful aging with that of the proportion meeting criteria for successful aging reported in previous studies.In both studies,signiﬁcantly more adults rated themselves as aging success-fully despite not meeting researcher-deﬁned criteria for successful aging,most often because of the presence of physical disabilities.Focus groups (Reichstadt et al.2007),in-dividual interviews (Andrews et al.2002),and survey instruments (Phelan et al.2004)have been used to examine the relative importance of individual domains of successful aging.In work with focus groups,Reichstadt et al.(2007)identiﬁed four largely psychological constructs discussed in regard to successful aging:(a )positive attitude/adaptation,(b )emotional security/stability,(c )health/wellness,and (d )engagement/stimulation.In contrast to the research deﬁnitions in which components were equally weighted,participants in the Reichstadt et al.(2007)study depicted suc-cessful aging as involving a foundation (e.g.,positive attitudes,security)that enabled stim-ulation/engagement.Knight &Ricciardelli (2003)and Phelan et al.(2004)found that older adults endorsed most research-deﬁned criteria as important to successful aging.However,Phelan et al.(2004)found that the relative importance of components of successful aging differed across Japanese,Japanese American,and European American respondents to a survey:European Americans were more likely to endorse independence as more important,whereas Japanese older adults ranked socialBiological age:index of aging-associated phenotypes that predict mortality/morbidity better than does chronological age Intermediatephenotypes:traits with greater reliability and less state dependencyAllostatic load:negative physiological effects of chronic exposure to stressbelonging as more important.Finally,Bowling &Iliffe (2006)contrasted ﬁve deﬁnitions of successful aging,including a multidimensional lay-based deﬁnition that included more subjec-tive variables than the other four deﬁnitions,patterned after research deﬁnitions described above.Interestingly,the lay-based deﬁnition was a stronger predictor of quality of life than were the biomedical deﬁnitions.Indices of BiologicalAge/Intermediate PhenotypesAt the other end of the research spectrum from qualitative approaches to uncovering the sub-jective aspects of successful aging,a number of empirical efforts have been made to develop in-tegrative indices of biological age.Described in depth elsewhere (Karasik et al.2005,Ravin-dranath et al.2002,Wilson 1988),indices of biological age are aimed at tracking the rate of biological aging by combining information from multiple intermediate phenotypes.An in-dex of biological age is validated by its ability to predict functioning and/or mortality better than chronological age or its individual con-stituents.Ideally,biological age would consist of a set of indicators of basic aging processes that are heritable,not solely related to disease ef-fects,and translatable across species.One could thus deﬁne successful biological aging as being biologically younger than one’s chronological age.A repeatable biomarker of aging could po-tentially serve as an outcome of interventions,as well.Allostatic load,for example,combines multiple physiological indicators converging on stress response,and expressed as an index has been shown to predict mortality better than its individual constituents or chronological age (O’Hara et al.2010).Critics of biological age are skeptical that a single indicator can provide meaningful sum-marization of the many causes of aging—thus,one may have multiple biological ages across different systems (McClearn 1997,Wilson 1988).In addition,given that biological age de-pends on its incremental validity over chrono-logical age,important aspects of aging that •Successful Aging19.5A n n u . R e v . C l i n . P s y c h o l . 2010.6. D o w n l o a d e d f r o m a r j o u r n a l s .a n n u a l r e v i e w s .o r g b y C h i n e s e A c a d e m y o f S c i e n c e s - I n s t i t u t e o f P s y c h o l o g y o n 01/26/10. F o r p e r s o n a l u s e o n l y .remain relatively stable over the lifespan are excluded (e.g.,emotional function).Nonethe-less,some nonage-dependent constructs (e.g.,adaptation)could be studied with intermedi-ate phenotypes (e.g.,emotional reactivity)that represent more translatable traits that are more closely related to physiological processes.Summary of Deﬁnitions of Successful AgingSuccessful aging has yet to attain a consensus deﬁnition among researchers and laypersons,with as many deﬁnitions as studies (Depp &Jeste 2006).However,there are noteworthy ar-eas of agreement in the literature—it is largely agreed that longevity is necessary but insufﬁ-cient to deﬁne successful aging and that success-ful aging is a multidimensional construct.Fur-thermore,among quantitative studies with an operationalized deﬁnition of successful aging,physical functioning/disability is included in nearly all deﬁnitions,and,on average,a minor-ity of older adults meet criteria for aging suc-cessfully,based on these deﬁnitions.In contrast to quantitative studies,qualitative approaches ﬁnd that most older adults believe they are ag-ing successfully,and lay deﬁnitions of successful aging are more likely to emphasize psycholog-ical adaptation and subjective well-being.Based on the divergences described above,it would be reasonable to question the utility of the construct of successful aging.It may be par-ticularly challenging to deﬁne a positive state of health because some individuals will invari-ably be excluded from the deﬁned positive state.There is also less of a clinical impetus to attain agreement about successful aging than would be the case in deﬁning a pathological state.How-ever,other multidimensional constructs in ag-ing research have attained consensus,have been subsequently adopted,and have advanced the ﬁeld (e.g.,frailty)(Fried et al.2001).Policy di-rectives,(Belza &Workgroup 2007,Cent.Dis-ease Control Prev.&Alzheimer’s Assoc.2007,U.S.Dept.Health Human Serv.2001)man-date investment in health-promotion programs targeting positive states of health,includingincreasing well-being and optimizing function-ing in later life;thus,there is a need to attain consensus so as to deﬁne success of these ini-tiatives.Furthermore,it is plausible that pre-dictors and mechanisms of “success”may differ from the lack of risk factors for poor states of health and functioning,necessitating research on the characteristics of the upper end of the continuum of aging (Rowe &Kahn 1987).A potential compromise is to focus on the determinants of success as individual compo-nents and to investigate the extent to which risk factors and interventions impact these compo-nents.Another rectiﬁable issue associated with the reviewed studies of successful aging is the diversity of measures used as indicators of the same construct,as well as the variation in di-chotomization schemes.Thus,even if there were agreement in which components to mea-sure,the variation among measures would still introduce variability.Recent trans-National In-stitutes of Health (NIH)initiatives,such as the Patient-Reported Outcomes Management In-formation System (PROMIS)(Fries et al.2005)and the NIH T oolbox initiative (Baughman et al.2006),are aimed at increasing the consis-tency among biobehavioral studies by identify-ing core sets of measures validated for different populations (including older adults).These ini-tiatives may aid in increasing consensus around deﬁnitions of successful aging.Increasing the Focus on Cognitive and Emotional AgingA prominent deﬁcit in the quantitative litera-ture is the comparative lack of focus on cog-nitive and emotional components of successful aging relative to physical functioning/disability.One reason for this may be that many of the quantitative studies reviewed drew from inves-tigations of physical disease (e.g.,cardiovascular illnesses).For example,measures used to delin-eate states of cognitive health were designed to rule out dementia or depression and thus may have limited sensitivity in distinguishing between normal and successful aging.Psycho-logical constructs described by older adults as19.6Depp·V ahia·JesteA n n u . R e v . C l i n . P s y c h o l . 2010.6. D o w n l o a d e d f r o m a r j o u r n a l s .a n n u a l r e v i e w s .o r g b y C h i n e s e A c a d e m y o f S c i e n c e s - I n s t i t u t e o f P s y c h o l o g y o n 01/26/10. F o r p e r s o n a l u s e o n l y .central to successful aging,such as resilience,were frequently omitted,in part because there are few well-accepted measures of such constructs.There is reason to increase the focus on cog-nitive and emotional health in relation to suc-cessful aging.First,in comparison to physical-functioning-based approaches to studying successful aging,cognitive and emotional phe-notypes may become more relevant in the fu-ture because neurodegenerative illnesses are less amenable to treatment than many other chronic physical illnesses at the present time (e.g.,Alzheimer’s disease is now the sixth leading cause of death,surpassing diabetes)(Alzheimer’s Assoc.2009).Second,cognitive and emotional processes mediate health be-haviors that impact physical health,and health behaviors are the foundation for most health-promotion programs in later life.Third,nearly all older adults will experience a chronic disease;very few centenarians have escaped these ill-nesses (Evert et al.2003).Thus,although avoid-ing chronic illness in late life is probably not a feasible goal,cognitive and emotional adapta-tion to these illnesses may well be attainable.Fourth,the phenotypes of successful aging de-scribed by older adults are largely psychological constructs rather than physical ones—Bowling &Iliffe (2006)showed that multidimensional lay-perspective-based deﬁnitions in compari-son with other deﬁnitions may in fact be more predictive of later quality of life.There is recent public health emphasis on increasing cognitive and emotional health in older age,as evidenced by several recent U.S.initiatives.In 2001,three Institutes of the NIH,the National Institute on Aging,the National Institutes of Mental Health (NIMH),and the National Institute of Neurological Disease and Stroke (NINDS),formed the Cognitive and Emotional Health Project (CEHP)(Hendrie et al.2006,2010).The Centers for Disease Control together with the Alzheimer Associ-ation have also recently published a report,“The Healthy Brain Initiative:A National Pub-lic Health Road Map to Maintaining Cog-nitive Health”(Cent.Disease Control Prev.Resilience:physical and/or emotional capacity to recover from stress or adversity CEHP:the NIH Cognitive and Emotional Health Project&Alzheimer’s Assoc.2007).These initiatives demonstrate the emerging interest in promot-ing states of cognitive and emotional health in older adults as complements to disease-focused initiatives.DETERMINANTS OF COGNITIVE AND EMOTIONAL HEALTHIn this section,we describe several putative de-terminants of successful aging,focusing on fac-tors associated with positive effects on cognitive and emotional phenotypes in older age.We do not restrict this review to the identiﬁed deter-minants of the quantitative deﬁnitions of suc-cessful aging described above (see Depp &Jeste 2006,Peel et al.2005).Instead,we take a broad approach to describing some the key mecha-nisms in selected positive constructs in cogni-tive and emotional aging.Genetic DeterminantsAlthough many studies have investigated the heritability of longevity (estimated to be ap-proximately 20%to 40%;Christensen et al.2006),fewer studies have investigated the her-itability of other phenotypes related to suc-cessful aging (e.g.,cognitive ability,function-ing)and fewer still the genetic contribution to multidimensional deﬁnitions of successful ag-ing such as those reviewed above.Uncovering the genetics of longevity has proven quite chal-lenging (Christensen et al.2006),and assess-ing the genetic contribution to successful ag-ing is made perhaps even more complex by the late age of onset,postreproduction (late pene-trance )of many phenotypes in older age,along with a multitude of indirect and direct inﬂu-ences of genes on disease and adaptive processes over the life course (Jazwinski 1996).Never-theless,a number of studies have found that later age of parental death is associated with bet-ter functional performance and cognitive ability in the offspring,suggesting that positive out-comes in aging may be heritable (Vaillant &Mukamal 2001).In a twin study,Gurland et al.(2004)estimated the heritability of 10indices of •Successful Aging19.7A n n u . R e v . C l i n . P s y c h o l . 2010.6. D o w n l o a d e d f r o m a r j o u r n a l s .a n n u a l r e v i e w s .o r g b y C h i n e s e A c a d e m y o f S c i e n c e s - I n s t i t u t e o f P s y c h o l o g y o n 01/26/10. F o r p e r s o n a l u s e o n l y .。

2015_-_Jian_Geng_-_Thestabilityofboundchloridesincementpastewithsulfa[retrieved_2015-09-23]

The stability of bound chlorides in cement paste with sulfate attackJian Geng a ,b ,⁎,Dave Easterbrook b ,Long-yuan Li b ,Li-wei Mo aa Research Center of Green Building Materials and Waste Resources Reuse,Ningbo Institute of Technology,Zhejiang University,China bSchool of Marine Science and Engineering,University of Plymouth,UKa b s t r a c ta r t i c l e i n f o Article history:Received 10July 2014Accepted 25November 2014Available online 27December 2014Keywords:Sulfate attack (C)Bound chlorides (D)Stability (C)Fly ash (D)Ground granulated blast-furnace slag (D)This paper presents an experimental investigation on the stability of bound chlorides in chloride-contaminated cement pastes with and without FA/GGBS when subjected to Na 2SO 4and MgSO 4attack.It is shown that bound chlorides were released in the chloride-contaminated pastes when exposed to Na 2SO 4or MgSO 4solution.This is mainly attributed to the decomposition of Friedel's salt (FS),where Cl −bound in FS is replaced by SO 42−.How-ever there were fewer released chlorides found in the pastes exposed to MgSO 4solution than in those exposed to Na 2SO 4solution.This is partly due to the low pH in the pore solution and partly due to the blocking effect of brucite on ionic transport caused by MgSO 4.The inclusion of FA/GGBS in concrete can increase the decomposition of FS and thus the release of bound chlorides.However,it also resists the penetration of Na 2SO 4and thus reduces the attack of Na 2SO 4.©2014Elsevier Ltd.All rights reserved.1.IntroductionThe corrosion of reinforcing steel in concrete structures,due to chlo-ride ion contamination,is one of the main reasons for the deterioration of concrete structures.There are two forms of chloride ions in concrete.One is free chlorides and the other is bound chlorides.It is well-known that the corrosion of reinforcing steel is mainly induced by the free chlo-rides,so reducing free chlorides by increasing bound chlorides will be bene ﬁcial to the durability of concrete structures.According to the bind-ing mechanism,chloride ions can be bound through chemical reactions and physical absorption.In the former,chloride ions are mainly bound in Friedel's salt (FS)(3CaO·Al 2O 3·CaCl 2·10H 2O)through hydration reactions between chloride ions,tricalcium aluminate (C 3A)and its hydration products.In the latter,chloride ions are mainly absorbed by calcium silicate hydrate (C –S –H gel).It was reported that the formation of bound chlorides could be affected by a multitude of factors such as the quantity of C 3A in cement,supplementary cementitious materials (SCM),alkalinity of pore solution,Ca/Si and Ca/Al of hydration products,chloride salt type,and service condition of concrete structures [1–5].In summary,the chloride binding capacity of concrete can be improved by using SCM or cement with high C 3A content.However,many researchers have identi ﬁed that the stability of bound chlorides,espe-cially of FS,can be affected by pH,carbonation,and chemical erosion [6–9].Sulfate attack is another problem for the durability of concrete struc-tures.The attack of sodium sulfate (Na 2SO 4)and magnesium sulfate (MgSO 4)on concrete is a common phenomenon.The mechanisms of Na 2SO 4and MgSO 4attack on concrete are different,mainly due to the solubility of phases formed with sodium and magnesium ions [10–12].With regard to Na 2SO 4attack,the deterioration of concrete is attributed to the formation of expansion products such as gypsum (CaSO 4·2H 2O)and secondary ettringite (AFt)(3CaO·Al 2O 3·3CaSO 4·32H 2O)according to the following equations:Ca ðOH Þ2þNa 2SO 4þ2H 2O →CaSO 4·2H 2O þ2NaOHð1Þ3ðCaSO 4·2H 2O Þþ3CaO ·Al 2O 3þ26H 2O →3CaO ·Al 2O 3·3CaSO 4·32H 2Oð2Þ2ðCaSO 4·2H 2O Þþ3CaO ·Al 2O 3·CaSO 4·12H 2O þ16H 2O →3CaO ·Al 2O 3·3CaSO 4·32H 2O :ð3ÞWhereas for MgSO 4attack,the transformation of the cementitious C –S –H gel to the non-cementitious magnesium silicate hydrate mush (M –S –H),which has very little strength,is the main reason for the dete-rioration of concrete,although gypsum and secondary AFt are also formed during the attack.In addition,brucite,i.e.Mg(OH)2,will form when magnesium is present in the pore solution,which has low solubil-ity and could densify the pore system and thus affect the transport ofCement and Concrete Research 68(2015)211–222⁎Corresponding author.E-mail address:gengjian@ (J.Geng)./10.1016/j.cemconres.2014.11.0100008-8846/©2014Elsevier Ltd.All rightsreserved.Contents lists available at ScienceDirectCement and Concrete Researchj o u rn a l h o m e p a g e :h t tp ://e e s.e l s e v i e r.c o m /C EM C O N /d e f a u l t.a s pions in the cement paste.The mechanism of MgSO4attack occurs according to the following equations:CaðOHÞ2þMgSO4þ2H2O→CaSO4·2H2OþMgðOHÞ2ð4Þx CaO·y SiO2·z H2Oþx MgSO4þð3xþ0:5y−zÞH2O→xðCaSO4·2H2OÞþx MgðOHÞ2þ0:5yð2SiO2·H2OÞð5Þ4MgðOHÞ2þSiO2·nH2O→4MgO·SiO2·8:5H2Oþðn−4:5ÞH2O:ð6ÞIn fact,sulfate attack and chloride contamination are often found to coexist in concrete structures which are exposed to marine and saline environments.The effects of the sulfate and chloride on a concrete structure's durability are multifaceted.On the one hand,the existence of sulfate,especially of Na2SO4,inhibits the formation of FS and reduces the quantity of bound chlorides[13–15].On the other hand,the exis-tence of chloride ions is beneﬁcial for the resistance of concrete to Na2SO4and MgSO4attack[15–18].However,Baghabra argued that the effect of chloride ions on MgSO4attack was slight because the trans-formation of cementitious C–S–H gel to non-cementitious M–S–H was not affected by chloride ions[19].Despite the work on the interaction of sulfate and chloride in con-crete mentioned above,there is very little work on the effect of sulfate attack on the stability of bound chlorides in concrete.Brown and Badger investigated the distributions of bound sulfates and chlorides inﬁeld concrete cores exposed to mixed NaCl,Na2SO4and MgSO4attack. They found that there was extensive AFt in the absence of a gypsum zone for some concrete cores[20].Xu et al.obtained similar results, i.e.that sulfate attack could lead to the release of bound chlorides[21]. Both studies suggested the transformation of FS to AFt due to sulfate attack,but the mechanism of FS transform to AFt and the stability of bound chlorides absorbed by C–S–H gel under sulfate attack were not discussed in depth.It is well known that the use ofﬂy ash(FA)and ground granulated blast-furnace slag(GGBS)in concrete can not only improve the chloride binding capacity of concrete,but also the resistance of concrete to sulfate attack[22,23].Hence,it would be interesting to know how they affect the stability of bound chlorides when the concrete is under sulfate attack.The purpose of this paper is to report the experimental in-vestigation on the stability of bound chlorides in cement paste under Na2SO4and MgSO4attack,and the corresponding inﬂuence of FA and GGBS on the stability of bound chlorides.The stability of bound chlorides in cement paste was examined by analyzing the change of a dimensionless index,R cl,which represents the mass ratio of bound chlo-rides to initial total chlorides in the sample after it was exposed to a5% Na2SO4solution or a5%MgSO4solution for28,56or90days.The mech-anisms of the release of bound chlorides are discussed based on the results of X-ray diffraction(XRD),Fourier transform infrared(FT-IR) and differential thermo-gravimetric analysis(DTG).2.Experiment2.1.MaterialsThe materials used in the experiments were Type42.5Ordinary Portland Cement(OPC),grade II FA and GGBS.The chemical composi-tions of OPC,FA and GGBS are listed in Table1.The potential phase com-positions of OPC,calculated from chemical analysis by Bogue,are given in Table2.All other chemical reagents used in the experiments,but not listed in the tables,are analytically pure.2.2.MethodsIn order to reduce the experimental running time but still able to achieve good and representative results,chloride binding was achieved by using0.5mol/L NaCl solution as the mixing water for the casting of samples.The mass ratio of the mixing water to the binder(cement and SCM)was0.5,which was the same for all samples.The inﬂuence of single and combined use of FA and GGBS on the stability of bound chlorides was also investigated.The replacement of cement with SCM was30%by weight,and the proportions of FA to GGBS in the combined samples were either1:1or7:3.The detailed mix proportions of the samples tested are listed in Table3.A total of106samples were tested.All samples were of a size of 40mm×40mm×160mm.There were three groups of samples.The ﬁrst group(2×5×7samples)were cured at a standard curing condi-tion(20±2°C and95%RH)for periods of1,3,7,14,28,56and90days for the investigation of the effect of curing time and SCM on the evolu-tion of bound chlorides in the cement paste.The second group(2×5×3 samples)were examined for the effect of Na2SO4attack on the stability of bound chlorides.In this group,all samples,after the56days standard curing,were dried at a room temperature(20±2°C and60%RH)for 1day.Then,for each sample itsﬁve surfaces were sealed by parafﬁn wax and one40mm×40mm surface was left untouched.After then, all samples were immersed in a covered plastic container(575mm ×400mm×275mm)of5%Na2SO4solution for28,56and90days at the standard curing condition(20±2°C and95%RH).The third group(2×1×3samples)were for the samples only with OPC,which were cured as the same as those done in the second group.The only dif-ference is that they were immersed in a similar covered container of5% MgSO4solution for28,56and90days at the standard curing condition (20±2°C and95%RH)for the examination of the effect of MgSO4at-tack on the stability of bound chlorides.The volume of the sulfate solu-tions used in the immersion tests was25L and the storage solutions were not renewed during the immersed tests.In the second and third groups,when the attack time reached28,56, and90days,the samples were dried at room temperature for1day,and then were sliced into four pieces parallel to the exposed surface (starting from the exposed surface)and each piece is one cm thick. Afterwards,each piece was broken into small blocks,which were then immersed in anhydrous ethanol for7days to terminate hydration. These small blocks were ground intoﬁne powder by passing through a sieve of0.15mm mesh aperture size,which was then stored in a des-iccator with silica gel and soda lime at11%RH to minimize carbonation before it was used in the tests for chloride content titration and other material characterization analyses.The initial total chloride content(C t)of the sample cured at the stan-dard curing condition can be calculated based on the mixing water of Table1Chemical composition of main materials(data presented by mass%).SiO2CaO MgO Fe2O3Al2O3SO3Ignition loss OPC19.6760.43 4.56 4.20 5.70 2.30 2.54FA43.10 6.300.247.2638.200.70 2.04GGBS23.5052.80 6.500.7011.80 1.650.78Table2Potential phase composition of OPC(data presented by mass%).Potential phase composition OPCC3S51.58C2S17.77C3A8.01C4AF12.773.91212J.Geng et al./Cement and Concrete Research68(2015)211–2220.5mol/L NaCl solution,which is 8.863mg ·g −1.The free chloride content (C f )was measured using the traditional leaching method according to the standard of Test Code for Hydraulic Concrete (SL352-2006)and the total chloride content (C t )was measured using the acid-soluble method (SL352-2006).In order to analyze the stability of bound chlorides in concrete,the dimensionless index (R cl )was exam-ined,which is de ﬁned as follows,R cl ¼C t −C f %ð7Þwhere 8.863mg.g −1is the initial total chloride content in the sample.X-ray diffraction (XRD)/reference intensity ratio (RIR)analysis and DTG can be used to approximately determine the quantity of FS,AFt and calcium hydroxide (CH)in the samples.XRD/RIR can determine the relative mass relations among different minerals in a sample,which is calculated according to the following equations [24,25]:W i ¼I i =RIR iX i ¼1I i=RIR i ðÞð8ÞW 1þW 2þW 3þ⋯þW l ¼1ð9Þwhere W i is the relative mass of mineral i ,RIR i is the reference intensityratio of mineral i ,which can be collected from the PDF card of the Inter-national Centre for Diffraction Data (ICDD),I i is the integral intensity of the highest peak of mineral i ,which is calculated using X'Pert HighScore Plus ™software,and N is the number of minerals in the sample.XRD/RIR is usually used to determine the quantity of substances in metals because of simple compositions [25].For cement based materials,it is rather complicated to accurately determine the kinds of hydration products,which increases the dif ﬁculty of the quantitative analysis.However,if the quantity of one of the minerals can be determinedusing other methods,the calculation process of XRD/RIR becomes pared with the FS and AFt,the quantity of CH can be accurately determined using DTG.Therefore,the quantities of the FS and AFt can be calculated by solving the following algebraic equations,m FS :m AFt ¼T 1ð10Þm FSFS þm AFt þm CH ¼T 2ð11Þm AFtm FS þm AFt þm CH ¼T 3ð12Þm CHm FS þm AFt þm CH¼T 4ð13Þwhere m FS ,m AFt and m CH are masses of FS,AFt and CH,respectively,T 1,T 2,T 3and T 4are the mass ratios,which can be calculated from Eqs.(8)and (9).Note that,m CH can be determined by DTG and thus m FS and m AFt can be determined by Eq.(10)plus any one taken from Eqs.(11)–(13).XRD was carried out using the D8Advance instrument of Bruker AXS with a Cu K αradiation generated with 40kV and 30mA.The diffraction spectra were collected in the range of 5–60°(2θ)scale,with a step sizeTable 3Mix proportions (data presented by mass %).Samples OPC FA GGBS w/b a NoteCN 100000.5Exposed to 5%Na 2SO 4solutionCF 703000.5CG 700300.5CF1G17015150.5CF7G3702190.5CM1000.5Exposed to 5%MgSO 4solutionaw/b represents the mass ratio of mixing water (i.e.0.5mol/L NaCl solution)to binder (cement +SCM).Fig.1.Variation of R cl with standard curing time in samples of differentmixes.Fig.2.Values of R cl in the surface layer of the sample at various different sulfate attack times (CM was exposed to MgSO 4,while all the others were exposed to Na 2SO 4).Fig.3.Values of R cl in different layers of the sample after 90days sulfate attack (1st layer is next to the surface and 4th layer is away from the surface.CM was exposed to MgSO 4,while all the others were exposed to Na 2SO 4).213J.Geng et al./Cement and Concrete Research 68(2015)211–222of 0.02°/s.FT-IR was performed for the samples on a Nicolet Nexus 470spectrometer using the KBr pellet technique in the range of 400–4000cm −1.DTG was carried out in a Netzsch TG-209F1thermal an-alyzer,using a heating rate of 20°C/min at the range of 25–1000°C,in N 2atmosphere.3.Stability of bound chlorides 3.1.Standard curing conditionThe variation of R cl during the standard curing time is shown in Fig.1.It can be seen from the ﬁgure that R cl in the samples with SCM is higher than that in the sample only with OPC when they have the same curing time,which is more obvious after the curing time exceeds 14days.Up to 28days,the combined use of FA and GGBS results in higher values of R cl in CF1G1and CF7G3than in the samples with only either FA (CF)or GGBS (CG).However,after the 28days standard curing,the R cl value of the samples has an order of CF ≈CF7G3N CF1G1N CG,which increases with the increased proportion of FA to GGBS.The latereffect of FA on chloride binding is mainly due to its slow pozzolanic re-action.The results shown in Fig.1indicate that the inclusion of SCM in concrete can increase the chloride binding capacity and the effect of FA on chloride binding is more signi ﬁcant than that of GGBS.Furthermore,they also show that the R cl values of all samples increase very obviously before 28days but after that there is less change,suggesting that the equilibrium between free and bound chlorides has been reached.3.2.Sulfate attack conditionFig.2shows the expected decrease in R cl of the surface layer of all samples with the sulfate attack,but the rate of the decrease is higher than that was reported [21].The R cl value in the surface layer of sample CN exposed to Na 2SO 4solution,for example,decreases from 59.8%to 4.3%after only 28days.After that,R cl continuously decreases with the attack time but with a slow reduction rate,from 4.3%at 28days to 1.9%at 90days.The results for locations other than the surface layer at 90days are shown in Fig.3.It can be seen from the ﬁgure that,although the 4th layer of sample CN is far away from theexposedFig.4.XRD patterns of samples CN(CM),CF and CG at standard curing condition for (A)28and (B)56days (E:ettringite (AFt),F:Friedel's salt (FS),CH:calcium hydroxide,M:mono-sulfoaluminate,V:Vaterite,CSH:C –S –H gel,C:calcite).214J.Geng et al./Cement and Concrete Research 68(2015)211–222surface,there is still a notable decrease in the R cl value from59.8%at the beginning of the Na2SO4attack to16.6%after90days of attack.This demonstrates that the stability of bound chlorides in concrete is very susceptible to Na2SO4attack.Note that the data plotted in Fig.2show that there is also a decrease in the R cl values of the samples with SCM after Na2SO4attack for28days, but the R cl values are still higher than that of the sample CN only with OPC.This suggests that the use of SCM can alleviate the effect of Na2SO4attack on the stability of bound chlorides.This is partly because the effect of SCM on the diffusion of ions,since the ionic diffusion coef-ﬁcient in cement paste with SCM is normally lower than that in OPC paste,and partly because the cement paste with SCM has more bound chlorides[26].Additionally,in contrast with the results obtained under the standard curing condition,the R cl values of the samples with SCM increase with the decreased proportion of FA to GGBS,and also the R cl value of the surface layer of sample CF is the lowest of all samples containing SCM,following the Na2SO4attack.This suggests that Na2SO4attack can also alter the effect of SCM on the stability of bound chlorides.This appears to be consistent with what is reported in literature[21].The stability of bound chlorides in concrete under MgSO4attack is also shown in Figs.2and3.When the MgSO4attack time extends from0to28days,the R cl value of the surface layer of sample CM decreases from59.8%to26.3%,which is slower than that of sample CN exposed to Na2SO4solution.When the attack time reaches90days, the R cl value of sample CM's surface layer decreases to7.5%,which is still almost four times as high as that of sample CN.This indicates that the stability of bound chlorides is less susceptible to MgSO4attack when compared with Na2SO4attack.Again,thisﬁnding is consistent with what is reported in other experiments[21,27].The different reductions of R cl in samples CM and CN reﬂect the different effects of MgSO4and Na2SO4on bound chlorides.During the immersion process free chloride ions will diffuse out and sulfate ions will diffuse into the specimen.The former may decrease the bound chlo-ride level in the sample owing to the equilibrium between the free and bound chlorides.The latter can transform FS into AFt,which not only can reduce the bound chlorides but also can change the pore system and thus affect the diffusion rate of ions.In addition,when magnesium is present,brucite will be formed,which can also change the pore sys-tem and thus affect the transport of ions and the R cl value.The slower reduction of R cl found in sample CM shown in Figs.2and3indicates that the magnesium ions must have some inﬂuence on the sulfate attack to the bound chlorides.This inﬂuence could be physical and/or chemi-cal.The former is mainly due to the forming of brucite in the surface layer,which reduces the inward diffusion of sulfate ions and the out-ward diffusion of chloride ions.Indeed,the measured free chloride con-centration after the90days immersion was found to be higher in sample CM than in sample CN and have the ratios of about1:0.72for the surface layer and1:0.81for the4th layer.An accurate analysis for the diffusion effect on the bound chlorides requires having more data on thinner layers and knowing the binding isotherms.Nevertheless, the above results did indicate that the diffusion of chloride ions was affected by magnesium ions.The chemical effect of magnesium ions on bound chlorides will be discussed in the next section.Note that the ionic diffusion coefﬁcient in concrete with SCM is nor-mally smaller than that in concrete only with OPC.Thus,the inclusion of SCM in cement paste can provide additional resistance to the ingress of sulfate ions,which in turn can affect the stability of bound chlorides. More discussion on this will be provided in the next section.4.Material characterization analyses4.1.X-ray diffractionThe XRD patterns of samples CN,CF and CG cured at the standard curing condition for28and56days are shown in Fig.4.From the XRD patterns one can identify the FS with a very obvious diffraction peak at around11°2θ.Fig.5shows the relative masses of AFt,FS and CH in samples CN,CF and CG after they were cured in the standard condition for56days.It can be seen from theﬁgure that the use of FA and GGBS is beneﬁcial to forming more FS.This result can be attributed to two rea-sons.First,the forming process of FS in concrete has been associated with the quantity of aluminate in cementious materials.The higher the quantity of aluminate,the more FS is formed.According to the chemical composition shown in Table1,there is a larger quantity of alu-minate in GGBS and FA than in OPC,which can be released due to the latent hydraulic property of GGBS and the pozzolanic property of FA, which is beneﬁcial to the formation of FS.Secondly,the formation of FS would be hindered because SO42−can react with aluminate prior to Cl−to form mono-sulfoaluminate(AFm)and AFt[13–15].In addition, C–A–H and C–S–H gel,formed due to the hydration reactions induced by FA and GGBS,are also beneﬁcial to chloride binding.As shown in Fig.5,although the quantity of aluminate in FA is higher than that in GGBS,the quantity of FS in sample CF is still lower than that in sample CG after standard curing for56days.It was believed that only reactive alumina Al2O3r−in SCM could react with Cl−to form FS[5].The quantity of CaO in FA used in this study is6.3%,which is low calciumﬂy ash according to Chinese speciﬁcation GB/T15696-2005,and where Mullite is the main form of Al2O3,so it is adverse to the formation of FS.Nevertheless,a notable decrease in the intensity of diffraction peak (IDP)of CH can be found in the XRD patterns of sample CF over the curing time from28to56days,which is induced due to the pozzolanic reaction between CH and FA.As a result,more C–S–H gel and C–A–H are formed,which could increase the bound chlorides in sample CF.It should be noticed that the IDP change at around30°(2θ)shown in Fig.4correlates with both C–S–H gel and calcite(CaCO3),because of the overlap of the two strongest diffraction peaks at29.25°(2θ)and 29.40°2θ,respectively[8,28].The XRD patterns of sample CN under Na2SO4attack are shown in Fig.6.It can be observed from Fig.6A that the IDP of FS in the surface layer of sample CN becomes very weak after Na2SO4attack for28 days,which indicates that FS has been decomposed due to the Na2SO4 attack.A quantitative analysis of FS,AFt and CH of sample CN after the Na2SO4attack for28and90days is shown in Fig.7.It can be seen from theﬁgure that the relative mass of FS in the sample decreases very quickly from2.04to0.45after the28days attack.This suggests that the stability of FS is very susceptible to Na2SO4attack,which may also explain why the decrease of R cl is quick as is shown in Fig.2.How-ever,when the attack time is extended from28to90days,the change in the quantity of FS is slight,which indicates that a large quantity of FShasFig.5.Analysis of ettringite(AFt),Friedel's salt(FS)and calcium hydroxide(CH)in sam-ples CN/CM,CF and CG after they had56days standard curing(wt.%represents the mass percentage of AFt/FS/CH in sample).215J.Geng et al./Cement and Concrete Research68(2015)211–222been decomposed following 28days of the Na 2SO 4attack.Moreover,it can be seen from Fig.7that the quantity of FS gradually decreases from the inside to the surface,which correlates with the change of the R cl value shown in Fig.3.In addition,one can see from Fig.6B that AFt with a diffraction peak at around 9°(2θ)can be detected in every layer of sample CN after the Na 2SO 4attack for 90days.The data shown in Fig.7for AFt indicate that the quantity of AFt in the fourth layer of sam-ple CN is higher than its initial value,which con ﬁrms that the attack of Na 2SO 4has reached the fourth layer of the sample.Fig.7also shows the expected opposite changes of FS and AFt with time.The XRD patterns of samples CF and CG after the Na 2SO 4attack for 90days are shown in Fig.8.Similar to the sample CN,the diffraction peaks of FS in the samples with SCM,especially in sample CF,become very weak.Similar to the analysis of the sample CN,Fig.9shows the relative mass of FS,AFt and CH of samples CF and CG after the Na 2SO 4attack for 90days.It seems that the quantities of FS in samples CF and CG are as high as that in sample CN after the Na 2SO 4attack.However,considering the higher quantity of FS in samples CF and CG before the Na 2SO 4attack as shown in Fig.5,the decrease of the quantity of FS in them is quicker than that in sample CN.Therefore,it can be concluded that the stability of FS in the samples with FA or GGBS is susceptible to Na 2SO 4attack when compared to the sample CN.The XRD patterns of samples CN and CM attacked by Na 2SO 4and MgSO 4for 90days are shown in Fig.10.An interesting ﬁnding is that there is still an obvious diffraction peak of FS in the sample CM,which is different from the sample CN attacked by Na 2SO 4.The analysis results shown in Fig.11demonstrate that there is more FS in sample CM than in sample CN.Therefore,it can be concluded that the Na 2SO 4attack has more effect on the decomposition of FS in hardened cement paste than the MgSO 4attack.In addition,the IDP of AFt in sample CM is lower than that in sample CN due to the different erosion mechanisms.However,there is still an obvious increase in AFt for sample CM from 0to 90days as demonstrated in Figs.5and 11,which indicates that MgSO 4attack can also lead to the formation of secondary AFt.NoteFig.6.XRD patterns of samples CN with Na 2SO 4attack.(A)1st layer at different days and (B)different layers at 90days (E:ettringite (AFt),F:Friedel's salt (FS),CH:calcium hydroxide,M:mono-sulfoaluminate,V:Vaterite,CSH:C –S –H gel,C:calcite).216J.Geng et al./Cement and Concrete Research 68(2015)211–222that,when magnesium is included in the exposure solution,brucite is formed at the expense of calcium hydroxide,which can affect not only the leaching of chloride from the specimen but also the inward trans-port of sulfate from the exposed solution and thus provide the in ﬂuence on the decomposition of FS and the formation of AFt.However,our XRD result did not reveal a signi ﬁcant amount of brucite and/or gypsum in the surface layer.This is probably due to the specimen layer used in the tests being too thick.Both Skaropoulou and Sotiriadis reported their test results in which brucite was detected in XRD patterns,but the IDP of it was very weak when compared to other phases [11,17].However,in other similar experiments brucite was not detected in XRD patterns [27,29,30].This is probably attributed to the consumption of brucite due to the formation of M –S –H as shown in Eqs.(4)–(6)[19].4.2.Fourier transform infrared (FT-IR)Fig.12shows the FT-IR spectra of sample CN after the Na 2SO 4attack for 28and 90days,respectively.The band at around 3640cm −1is due to the stretching vibration of \OH in Ca(OH)2[30],which is very weak in all samples due to Na 2SO 4attack.The presence of carbonate bands at around 1430and 870cm −1indicates that the samples have already absorbed CO 2molecules from the air before they were immersed into sulfate solution [31].The band at around 1110cm −1comes from asym-metric stretching vibration of S –O in SO 42−,which is identi ﬁed as the ﬁngerprint peak of AFt [32,33].As is shown in Fig.12,owing to more secondary AFt being formed,this band becomes stronger from the in-side to the surface over the attack time.The changes in the bands at around 3440and 1650cm −1are due to the stretching vibration of \OH in structural water of hydration products and the bending vibra-tion of \OH in the interlayer water of hydration products [30].The two bands are also related to the formation of secondary AFt,which be-come strong with the increased quantity of secondary AFt.In addition,the band at around 970cm −1comes from asymmetric stretching vibra-tion of Si –O in C –S –H gel [31,34].It can be observed from Fig.12that there is no obvious change in this band over the attack time,which sug-gests that the stability of C –S –H gel is independent of Na 2SO 4attack.With regard to FS,because chloride ions are not absorbed in the range 400–4000cm −1,the bands at around 730,530and 460cm −1,which are due to Al –O vibrations of [Al(OH)6]3−,can be identi ﬁed as the ﬁn-gerprint peaks of FS [35,36].Owing to the decomposition of FS under Na 2SO 4attack,the strength of these bands appears very weak.Fig.13shows the FT-IR spectra of samples CF and CG after the Na 2SO 4attack.There is no obvious band at around 3640cm −1in thespectra due to the consumption of CH induced by hydration reactions of FA and GGBS and sulfate attack.It can be observed from Fig.13that there is an increase in the strength of the band of C –S –H gel at 976cm −1in sample CF over the attack time from 56to 90days.Guerre-ro et al.attributed this to the further activating action on FA due to the increase in alkalinity induced by Na 2SO 4attack [15].Moreover,this re-sult also indicates that the stability of C –S –H gel is independent of Na 2SO 4attack.The difference of the bands at 714,535and 458cm −1be-tween samples CF and CG is slight.Fig.14shows the FT-IR spectra of samples CN and CM after Na 2SO 4and MgSO 4attack for 90days,respectively.It is observed from Fig.14that the strength of the band at around 710cm −1in sample CM is much stronger than that in sample CN.Also there is more FS in sample CM than in sample CN,which agrees with the results shown in Figs.10and 11.Moreover,it can be seen clearly from Fig.14that the strength of the band at around 970cm −1in sample CM is lower than that in sample CN.This is likely attributed to the decomposition of C –S –H gel induced by MgSO 4attack.As a result of that,the bound chlorides absorbed by C –S –H gel are released.A weak band at around 1110cm −1in sample CM due to the attack of MgSO 4can induce the formation of secondary AFt.4.3.Derivative thermo-gravimetric analysis (DTG)The DTG curves of sample CN attacked by Na 2SO 4are shown in Fig.15.There are some notable endothermic peaks in the DTG curves.The peak near 100°C is mainly attributed to the dehydration of C –S –H gel and AFt,which are dif ﬁcult to distinguish because of the overlap of dehydration temperature from 85to 130°C [23].The peak near 160°C is attributed to AFm [23].Besides these,the peaks near 340,450and 710°C are attributed to the dehydration of FS,CH and the decomposi-tion of calcite.The absence of the peak for FS in the DTG curve after the Na 2SO 4attack for 28days shown in Fig.15further demonstrates that the stability of FS is susceptible to Na 2SO 4attack.The change in the peak of AFm,which plays an important role in the formation of sec-ondary AFt during the Na 2SO 4attack,is also consistent with the change of FS.Fig.16shows the DTG curves of samples CF and CG after the Na 2SO 4attack for pared to sample CG,sample CF has a weak strength of the peak for FS,which is consistent with the analysis result shown in Fig.9and the R cl data shown in Fig.2.Fig.17shows similar DTG results of samples CN and CM after Na 2SO 4and MgSO 4attack for 90days.It is noticed from the ﬁgure that the strength of the peak for C –S –H gel and AFt in sample CM is far lower than that in sample CN.Ac-cording to the FT-IR results shown in Fig.14,this result further indicates that MgSO 4attack will lead to the decomposition of C –S –H gel,resulting in the release of bound chlorides.5.Discussion5.1.Stability of Friedel's saltSuryavanshi and Swamy reported that a drop in alkalinity of pore so-lution due to carbonation could induce the decomposition of FS [8].Con-versely,Na 2SO 4attack can increase the alkalinity of the pore solution,which has a negative effect on chloride binding [23,27,37].The question now is how Na 2SO 4attack affects the stability of FS.The exchange be-tween Cl −and SO 42−is the main mechanism in the formation of FS,which can be explained by the following reaction [27]:3CaO ·Al 2O 3·CaSO 4·12H 2O ðAFm Þþ2Cl −→3CaO ·Al 2O 3·CaCl 2·10H 2O ðFS ÞþSO 2−4þ2H 2O :ð14ÞEssentially,FS belongs to a phase of the AFm family,which has a complex chemical and structural constitution.A general formula for AFm phase is [Ca 2(Al,Fe)(OH)6]+X·m H 2O,where the bracketsindicateFig.7.Analysis of ettringite (AFt),Friedel's salt (FS)and calcium hydroxide (CH)in sample CN after Na 2SO 4attack for 0,28and 90days (wt.%represents the mass percentage of AFt/FS/CH in sample).217J.Geng et al./Cement and Concrete Research 68(2015)211–222。

1-s2.0-S0263436814001590-main

Effect of rare earth elements on the consolidation behavior and microstructure of tungsten alloysMingyue Zhao a ,Zhangjian Zhou a ,⁎,Qingming Ding a ,Ming Zhong a ,Kameel Arshad ba School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China bSchool of Physics and Nuclear Energy Engineering,Beihang University,Beijing 100191,Chinaa b s t r a c ta r t i c l e i n f o Article history:Received 11February 2014Available online 23July 2014Keywords:Rare earth element Tungsten alloyConsolidation behavior MicrostructureThe effects of rare earth elements (Y 2O 3,Y and La)on the consolidation behavior,microstructure and mechanical properties of tungsten alloys were investigated in this work.The starting powders were mechanical alloyed (MA)and then consolidated by spark plasma sintering (SPS).It was found that Y doping was bene ﬁcial to obtain fully dense tungsten alloys with more re ﬁned grains as compared to any other rare earth elements.The maximum values of Vickers microhardness and bending strength obtained from W –0.5wt.%Y alloy reached up to 614.4HV 0.2and 701.0MPa,respectively.©2014Elsevier Ltd.All rights reserved.IntroductionTungsten is a promising candidate material for high temperature applications due to its attractive properties,such as high melting point,high conductivity,low thermal expansion coef ﬁcients and low sputtering yield [1].However,a major limitation of its use is the inherently high ductile –brittle transition temperature (DBTT)and low recrystallization temperature.Fine grained tungsten materials have shown improved properties in terms of reduced brittleness and improved toughness and strength [1,2].However,the improved mechanical properties will be deteriorated when exposed to high temperatures for long time and when the service temperature is higher than the recrystallization temperature of pure tungsten.Recent studies suggested that the dispersion of high temperature oxide nanoparticles,such as La 2O 3and Y 2O 3,will not only inhibit the grain growth of W during the consolidation but also stabilize the microstructure when exposed to higher temperature [3,4].It is well known that,the impurities,especially for oxygen,have det-rimental in ﬂuence on the sinterability of tungsten powders and make tungsten materials embrittlement.Thus adding rare earth elements in the metallic state instead of the oxidic state should be better for fabrica-tion of high performance tungsten alloys,due to the high af ﬁnity of rare earth elements with oxygen.A recent research conducted by L.Veleva et al.[5]found that the relative density of W –(0.3–2)wt.%Y appeared higher than that of W –(0.3–2)wt.%Y 2O 3,however,the microhardnessappeared always lower than that of W –(0.3–2)wt.%Y 2O 3.From the viewpoint of oxygen absorption,it is suggested that La will be better than Y when used as alloying element for fabrication of W [6].However there are almost no reports on W –La alloy and their comparison with W –Y alloy.It will be interesting and important to investigate the effects of different rare earth elements on the densi ﬁcation of W and their mechanical properties.This is the motivation of this work.In this study the effect of rare earth elements,including Y 2O 3,Y and La on the consolidation behavior of W under the same sintering condi-tion was investigated.The microstructural evolution and mechanical properties of different rare earth tungsten materials were examined and compared.Experimental proceduresPowders of commercial pure W (with an average particle size of 2.0μm and a purity of 99.9%),rare earth element of Y or La (with an av-erage particle size of 48μm and a purity of 99.9%),and rare earth oxide of Y 2O 3(with an average particle size of 30nm and a purity of 99.9%)were used as starting materials.The mixture powders of W –0.5wt.%Y 2O 3(named as WYO),W –0.5wt.%Y (named as WY)or W –0.5wt.%La (named as WL)were mechanical alloyed (MA)in a planetary ball mill,respectively.The MA parameters can be found in our previous work [7,8].Then,the MA treated powders were placed into graphite tool in glove box and sintered by spark plasma sintering (SPS)in vacuum.Fig.1shows the temperature and pressure pro ﬁle of SPS as a function of time.In order to get fully dense bulk materials by suppress-ing the pore-boundary separation,the samples were ﬁrst sintered at 1373K for 2min and then sintered at 1873K according to [9].Int.Journal of Refractory Metals and Hard Materials 48(2015)19–23⁎Corresponding author at:Laboratory of Special Ceramics and Powder Metallurgy,School of Materials Science and Engineering,University of Science &Technology Beijing,Beijing 100083,PR China.Tel./fax:+861062334951.E-mail address:zhouzhj@ (Z.Zhou)./10.1016/j.ijrmhm.2014.07.0140263-4368/©2014Elsevier Ltd.All rightsreserved.Contents lists available at ScienceDirectInt.Journal of Refractory Metals and Hard Materialsj o u r n a l h o m e p a g e :w w w.e l s e v i e r.c o m/l o c a t e /I J R M H MThe shrinkage of the specimens was continuously monitored by the displacement of the punch rod.The density of the compacts was measured by Archimedes method.A ﬁeld emission scanning electron microscope (FE-SEM)equipped with Energy-dispersive X-ray Spectros-copy (EDS)and Scanning electron microscope (SEM)were employed to investigate the microstructural features,i.e.,the element distribution,and the size and morphology of the grains and the pores of the samples.Moreover,XRD was used to determine the phase and X-ray diffraction analysis was made by the Rietveld method using the Full prof program [10].The average crystallite size as well as the internal stress of the MA treated powders were determined from the diffraction peak widths taking into account the diffractometer resolution function.Vickers mi-crohardness was measured at room temperature by applying a load of 1.96N for 15s.Three point bending tests were conducted on specimens with dimensions of 2mm ×3mm ×18mm with a span of 13.1mm and a crosshead speed of 0.5mm/min.The thermal behavior of the MA treated powders in the range 373–1723K was investigated by differen-tial scanning calorimetry (DSC)at a heating rate of 10K/min in ﬂowing pure Ar.Results and discussion Consolidation behaviorFig.2compares the consolidation behavior of all tungsten alloys as a function of temperature.It can be clearly seen that the displacement of WY alloy is similar with that of WL alloy,and shows quite different ten-dency from that of WYO alloy,especially at the sintering temperature of 1373K.For WY and WL alloys,the displacement decreased by 0.6mm between 993K and 1373K due to the thermal expansion of graphite punch rods and the matrix overweighing the contribution of pre-compaction,and continued to decrease at the sintering temperature of 1373K.For WYO alloy,the displacement experiences a slower down-ward trend between 993K and 1373K and a weak upward trend at 1373K.After that,the displacement of WY sees a similar trend with that of WYO.It was found that the WY alloy experienced a substantial decrease in the displacement while the WYO alloy experienced a slight increase at the temperature of 1373K.This result is likely to arise from the formation of a higher volume of Y 2O 3due to the oxidation of Y ele-ment in the WY system.Chemical analysis of the consolidated compacts was performed by the HORIBA EMIA-820V and LECO TCH600devices to measure the C and O contents,respectively.It shows that the C contents were about 240ppm for various tungsten materials fabricated under the same conditions.The amount of oxygen content which existed in MA treated WY powders was 0.4808wt.%,which is enough for the reactionwith added Y particles to form Y 2O 3.Fig.3shows the DSC curve of the MA treated WY powders in the range 373–1723K.A weak exothermic peak at 1500K with an onset temperature of 1400K is found.It probably corresponds to the oxidation of the metallic Y with the residual oxygen in a hermetically sealed pan,which also illustrates that the remaining Y particles are likely to start to react with oxygen around 1373K during SPS.Moreover,a sharp strong and a small exothermic peak can be clear-ly seen at 1003K and 1173K,respectively.According to [11,12],these peaks indicate that the strain relief took place during the heating of MA treated powders.Similar results on the oxygen analysis and the thermal behavior are also found for MA treated WL powders.Fig.4shows the milling and sintering effect on the XRD patterns of the investigated samples.It is obvious that the diffraction peaks are broadened after milling,which was caused by the re ﬁnement of powder particles and a high level of internal strain in the W grains fabricated by the MA process.After sintering,the diffraction peaks become narrow again due to the grain growth and strain relief.The quantitative data on such grain growth and strain relief can be obtained by the compari-son of lattice parameters after each stage of the powder processing (Table 1).It should be noted that the XRD patterns for all samples after milling exhibit a single BCC phase,suggesting that the rare earth elements were dissolved into the W lattice.This solid solutionduringFig.1.The temperature and pressure pro ﬁle as a function of time for the sintering experiments of rare earth tungstenalloys.Fig.2.The real time sintering curves of all samples without removing the contribution of the thermal expansion of the graphite tool andmatrix.Fig.3.DSC curve of the MA treated WY powder.The peak temperatures of thermally induced transformation of the powders are indicated by arrows.20M.Zhao et al./Int.Journal of Refractory Metals and Hard Materials 48(2015)19–23the MA process can be further demonstrated by the lattice parameter increase of the MA treated powders compared with that of the starting pure tungsten powder (Table 1).Microstructure observationMicrostructure of the fracture surfacesThe fracture surfaces of WY,WYO and WL samples are presented in Fig.5.It can be clearly seen that the rare earth elements in ﬂuence the grain re ﬁnement signi ﬁcantly.Fig.6shows the grain size distribution which was determined from the SEM micrographs of fracture surfaces.For each image,about 130grains were chosen randomly to eliminate the bias of grain counting.The grain size distributions of WL and WYO alloys are in the range from 1.6to 8.0μm and from 0.8to 4.4μm,respec-tively,and their average grain sizes are 2.46μm and 4.62μm,respective-ly;while,the average grain size of WY alloy is only 1.10μm,which is much smaller than that of WL and WYO alloys.The grain size distribu-tion of WY alloy is in the range from 0.3to 2.0μm,which is much nar-row as compared with that of WL and WYO alloys.Moreover,it is worth noting that the average grain size acquired from the SEM images of fracture surfaces has a remarkable consistency with those calculated by the Rietveld method using the Full prof program,as shown in Table 1.More careful analysis of Fig.6reveals that the WY alloy is denser than WYO and WL alloys.Many big worm-like pores (indicated by yel-low arrows)and small pores (indicated by white dot circles)can be found for WYO and WL alloys on the surface of individual tungstengrains and in the triple junctions.It is easy to learn that the tungsten grains with different additions grew up in a different speed (WL N WYO N WY)according to the average grain size of each stage of powder processing.Besides,the grain growth of pure tungsten or ODS W-based materials sintered by SPS starts between 1373K and 1773K according to literature [9,13].Under a certain pressure between 1773K and 1873K in our present work,the smaller the grain size,the easier the re-arrangement and plastic deformation,and thus higher shrinkage can be achieved.During the holding time at sintering temperature (1873K),grain growth took place simultaneously with further densi ﬁcation,which was achieved dominantly by more homogeneous interfacial atomic diffusion but with minimized involvement of surface diffusion according to [9].Meanwhile,the worm-like pores could be formed if the holding time at sintering temperature of 1873K was not enough for W –0.5La alloy having a large grain size.The microstructure of chemically etched surfacesThe microstructures of chemically etched surface are illustrated in Fig.7.EDS analysis indicated that the black phases which existed in WYO,WY and WL alloys are rare earth oxides (indicated by blue ar-rows)and the dark gray phases are pores (indicated by red arrows).For WY alloy (Fig.7b),pores can hardly be found,which is consistent with the microstructure observation of the fracture surface.Besides,ﬁne Y 2O 3particles are distributed uniformly along grain boundaries of WY alloy;while for WYO and WL alloys (Fig.7a and c),many micro-scale pores are found in triple junctions and tungsten grain boundaries,especially for WL alloy.Moreover,the FESEM images shown in Fig.7a and c reveal that the oxide particles are irregular and not distributed uniformly.In the XRD measurements performed on the WL alloy (Fig.4and Table 1),a weak diffraction peak of La 2O 3phase and lattice parameter decrease of sintered WL alloy are observed,which also suggest that the La particles separate from tungsten grains and become micro-scale La 2O 3during sintering.The densi ﬁcation analysisTable 2shows the relative density of the rare earth tungsten alloys.The relative density of WY reaches 99.4%,which is much higherthanFig.4.Effect of milling and SPS sintering on the XRD patterns of rare earth tungsten alloys.(a)MA treated powders,and (b)sintered compacts.Table 1Lattice parameters after each stage of the powder processing and the average grain size ac-quired from the SEM images of fracture surfaces.SamplePowder Sintered compact Crystallite size (nm)lattice strain (%)a (W:nm)Grain size (nm)Lattice strain (%)Grain size (nm)—SEM WY 8050.3510.31646215220.0701100WL 4100.3010.31659956650.0414620WYO 6200.3860.31653424820.0342460W11740.0450.31604021M.Zhao et al./Int.Journal of Refractory Metals and Hard Materials 48(2015)19–23the WYO (92.1%)and WL (88.3%).This result is agreeable with the mi-crostructure observation.Owing to the grain boundary cleaning effect and sintering enhancing effect of Y particles during SPS,Y doping is ben-e ﬁcial to achieve fully dense tungsten alloys than Y 2O 3doping.On the other hand,the well-distributed ﬁne Y 2O 3dispersions which existed in WY alloy play a prominent role in the re ﬁnement of tungsten grains,thus dense ﬁne grained sample can be obtained under the present sintering process.Kim et al.[14]reported that the second phases can act as obstacles in inhibiting the grain growth only in solid phase sintering.Owing to the formation of metallic La liquid phase at 1193Kaccording to the phase diagram Mo –La and then the formation of micro-scale and non-uniformly distributed La 2O 3dispersions as a result of oxidation,the grain growth speed of WL alloy is much higher than that of WYO and WY alloys.Thereby,the relative density of WL alloy is lower than that of WYO alloy and WY alloy even though La particles can exert cleaning effect on the tungsten grain boundaries.Besides,in accordance with literatures [4,15,16],the internal energy originating from the signi ﬁcant strain of the particles could serve as a part of sintering driving force.As shown in Table 1,the lattice strain of WL alloy is 0.301%,lower than that of WYO (0.386%)and WY (0.351%),which is another reason for the lower relative density of WL alloy.The basic mechanical propertiesVickers microhardness and bending strength of the rare earth tung-sten alloys were also listed in Table 2.Of all the three kinds of tungsten materials,the hardness of WY sample is 614.4HV 0.2,much higher than that of WYO (445.2HV 0.2)and WL (303HV 0.2).The lower hardness of WYO and WL alloys originates from the lower relative density and coarse grain size,as shown in Figs.5and 6.Moreover,WY exhibits the highest bending strength (701MPa)among these tungsten alloys,which is 11%and 88%higher than that of WYO and WL alloys.As shown in Fig.5,the remaining pores,including worm-like pores and small pores,reduce the contact area of tungsten grains,thus the bending strength of WYO and WL to some extent decreases.Besides,the coarse grain size (Fig.6)and inhomogeneous dispersions of oxide particles (Fig.7)of WYO and WL alloys are also the reason for their low bending strength.ConclusionsTungsten alloys were successfully fabricated by adding different rare earth elements to W matrix.The effect of dispersing rare earthelementsFig.5.SEM micrographs of fracture surfaces for:(a)WYO,(b)WY,and (c)WL;the yellow arrows denote worm-like pores existed on the surface of individual grains,and the white dot circles denote pores located in the triplejunctions.Fig.6.Histograms of the grain size distributions for WYO,WY and WL alloys.22M.Zhao et al./Int.Journal of Refractory Metals and Hard Materials 48(2015)19–23on the microstructure evolution and mechanical properties of the tung-sten alloys can be concluded as follows:(1).The relative density of WY,WYO and WL alloy reached 99.4%,92.1%and 88.3%,respectively.The Y doping was bene ﬁcial toobtain fully dense tungsten alloys as compared with Y 2O 3doping and La doping because the ﬁnely distributed second phase parti-cles suppressed the tungsten grain growth and thus ensured the suf ﬁcient grain boundary volume available for densi ﬁcation by grain boundary diffusion.The analysis of consolidation behavior and thermal behavior of MA treated WY or WL powders revealed that the added Y or La particles were likely to start to react with oxygen around 1373K during SPS.(2).The average grain sizes of WY,WYO and WL alloys were 1.10μm,2.46μm and 4.62μm,respectively.The Y doping was bene ﬁcial to obtain tungsten alloys with more re ﬁned tungsten grains as com-pared with Y 2O 3doping and La doping.(3).Of all the three kinds of rare earth tungsten alloys,WY alloy ex-hibited the highest mechanical properties at room temperature.The maximum values of Vickers microhardness and bending strength reached up to 614.4HV 0.2and 701.0MPa,respectively.AcknowledgmentsThe authors would like to express their thanks for the ﬁnancial support of the National Natural Science Foundation of China under grant No.50634060.References[1]Zhang Y,Ganeev AV,Wang JT,Liu JQ,Alexandrov IV.Observations on the ductile-to-brittle transition in ultra ﬁne-grained tungsten of commercial purity.Mater Sci Eng A 2009;503:37–40.[2]Kitsunai Y,Kurishita H,Kayano H,Hiraoka Y,Igarashi T,Takida T.Microstructure andimpact properties of ultra-ﬁne grained tungsten alloys dispersed with TiC.J Nucl Mater 1999;271–272:423–8.[3]Kim Y,Lee KH,Kim E,Cheong D,Hong SH.Fabrication of high temperature oxidesdispersion strengthened tungsten composites by spark plasma sintering process.J Refract Met Hard Mater 2009;5:842–6.[4]Wang HT,Fang ZZ,Hwang KS,Zhang HB,Siddle D.Sinter-ability of nanocrystallinetungsten powder.Int J Refract Met Hard Mater 2010;28:312–6.[5]Veleva L,Oksiuta Z,Vogt U,Baluc N.Sintering and characterization of W –Y andW –Y 2O 3materials.Fusion Eng Des 2009;84:1920–4.[6]Brown PH,Rathjen AH,Graham RD,Tribe DE.Chapter 92rare earth elements inbiological systems.Handbook on the physics and chemistry of rare earths;1990.p.423–52.[7]Zhou ZJ,Tan J,Qu DD,Pintsuk G,Rödig M,Linke J.Basic characterization of oxidedispersion strengthened ﬁne-grained tungsten based materials fabricated by me-chanical alloying and spark plasma sintering.J Nucl Mater 2012;431:202–5.[8]Tan J,Zhou ZJ,Zhu XP,Guo SQ,Qu DD,Lei MK,et al.Evaluation of ultra-ﬁne grainedtungsten under transient high heat ﬂux by high-intensity pulsed ion beam.Trans Nonferrous Metals Soc China 2012;22:1081–5.[9]Ma J,Zhang JZ,Liu W,Shen ZJ.Suppressing pore-boundary separation during sparkplasma sintering of tungsten.J Nucl Mater 2013;438:199–203.[10]Rodríguez-Carvajal J.Recent advances in magnetic structure determination byneutron powder diffraction +FullProf.Physica B 1993;192:55–6.[11]Muñoz A,Monge MA,Savoini B,Rabanal ME,Garces G,Pareja 2O 3-reinforced Wand W –V alloys produced by hot isostatic pressing.J Nucl Mater 2011;417:508–11.[12]Maweja K,Phasha MJ,Choenyane LJ.Thermal stability and magnetic saturation ofannealed nickel –tungsten and tungsten milled powders.J Refract Met Hard Mater 2012;30:78–84.[13]Yar MA,Wahlberg S,Bergqvist H,Salem HG,Johnsson M,Muhammed M.Spark plas-ma sintering of tungsten –yttrium oxide composites from chemically synthesized nanopowders and microstructural characterization.J Nucl Mater 2011;412:227–32.[14]Kim Y,Hong MH,Lee SH,Kim EP,Lee S,Noh JW.The effect of yttrium oxide on thesintering behavior and hardness of tungsten.Met Mater Int 2006;12:245–8.[15]Han Y,Fan JL,Liu T,Cheng HC,Tian JM.The effects of ball-milling treatment on thedensi ﬁcation behavior of ultra-ﬁne tungsten powder.Int J Refract Met Hard Mater 2011;29:743–50.[16]Prabhu G,Chakraborty A,Sarma B.Microwave sintering of tungsten.Int J Refract MetHard Mater 2009;27:545–8.Fig.7.FESEM micrographs of chemically etched surface of:(a)WYO,(b)WY,and (c)WL.Table 2The relative density and basic mechanical properties of rare earth tungsten alloys.Sample Relative density (%)Microhardness (HV 0.2)Bending strength (MPa)WYO 92.1445.2631WY 99.4614.4701WL88.3303372.123M.Zhao et al./Int.Journal of Refractory Metals and Hard Materials 48(2015)19–23。

《品质》 PPT

坚守理想
品质严肃认真、不擅交际
格斯拉的人品
• 技艺高超 • 真诚朴实 • 正直善良 • 恪守职业道德 • 坚持原则品质
三、细读文本，体味描写艺术
• 高尔斯华绥1932年获诺贝尔文学奖，颁奖词是：因其描述的卓越艺术
品质
那几双靴子太美观了——有一双轻跳舞靴，细长到非言语所能形容的地步；那双带布口的漆皮靴，叫人看了舍不得离开；还有那双褐色长筒马靴，闪着怪异的黑而亮的光辉，虽然是簇新的，看来好像已经穿过一百年了。（2）
但是当我走近他的店铺所在地时，我发现他的姓氏不见了。橱窗里照样陈列着细长的轻跳舞靴、带布口的漆皮靴，以及漆亮的长筒马靴。（54）
品质
他回答说：“这是一种手艺。”从他的含讽带刺的红胡根上，突然露出了一丝的微笑。（4）
他眼睛盯着皮革对我说：“多么美的一张皮啊！”（10）
他把手里的皮革举起来说，“这是一张美丽的皮革。”（41）
他肯用最好的皮革，而且还要亲自做。（64）
思考：一个用生命坚守着社会良知的高尚的普通劳动者，有如此高超的手艺怎么会饿死?
思考：一个用生命坚守着社会良知的高尚的普通劳动者，有如此高超的手艺怎么会饿死?
思考：一个用生命坚守着社会良知的高尚的普通劳动者，有如此高超的手艺怎么会饿死?
不让任何人碰他的靴子——过分认真；接一份订货后，要费好长时间去做它——费时长；从早到晚在那里做靴子——不知休息；从不登广告——经营理念陈旧；只用最好的皮革——成本过高；店里从来不存一个便士，所有的钱都用在房租和皮革上了——不懂经营；不注意同行竞争——不能积极应对竞争。
小说主题
• 小说以工业垄断对手工业作坊的冲击为背景，客观地描写手工业者的生存危机，赞扬鞋匠格斯拉纯洁朴实、诚实守信、恪守职业道德的高尚品质，表现出对底层劳动者的尊重，同时借这个形象，揭露了工业革命、市场竞争带来的商业诚信危机。

Jpsi suppression in heavy ion collisions - interplay of hard and soft QCD processes

a rXiv:h ep-ph/981486v126Oct1998J/ψsuppression in heavy ion collisions –interplay of hard and soft QCD processes C.Spieles 1∗†,R.Vogt 1,2,L.Gerland 3,S.A.Bass 4∗,M.Bleicher 3,L.Frankfurt 3,5∗,M.Strikman 6,H.St¨o cker 3,W.Greiner 31Nuclear Science Division,Lawrence Berkeley National Laboratory,Berkeley,CA 94720,USA 2Physics Department,University of California at Davis,Davis,CA 95616,USA 3Institut f¨u r Theoretische Physik,J.W.Goethe-Universit¨a t,D-60054Frankfurt a.M.,Germany 4Department of Physics,Duke University,Durham,N.C.27708-0305,USA 5School of Physics and Astronomy,Tel Aviv University,69978Ramat Aviv,Tel Aviv,Israel 6Department of Physics,Pennsylvania State University,University Park,PA 16802,USA Abstract We study J/ψsuppression in AB collisions assuming that the charmonium states evolve from small,color transparent conﬁgurations.Their interac-tion with nucleons and nonequilibrated,secondary hadrons is simulated us-ing the microscopic model UrQMD.The Drell-Yan lepton pair yield and the J/ψ/Drell-Yan ratio are calculated as a function of the neutral transverse en-ergy in Pb+Pb collisions at 160GeV and found to be in reasonable agreement with existing data.I.INTRODUCTIONExperimental data on the AB and E T dependence of J/ψ-meson production from the CERN SPS[1–4]exhibit tantalizing evidence for J/ψsuppression when compared to hard QCD production.Do the J/ψdata in Pb+Pb-collisions indicate the creation of a deconﬁned phase of strongly interacting matter,i.e.a quark-gluon plasma(QGP)[5,6]?Such QGP scenarios generally rely on the experimental observation of deviations from the predictions of models of hadronic suppression.Simple analytical models of J/ψsuppression have used nuclear absorption alone[5]or absorption by nucleons and comoving secondaries[7]toﬁt all but the Pb+Pb data.These models generally assume a single,ﬁxed nucleon absorption cross section for all charmonium states and that the comover interaction rate,assuming a Bjorken scaling expansion,is essentially thermal.(For theoretical reviews,see Refs.[8–10].)1 Charmoniumﬁnal state interactions with mesons and baryons are simulated using the Ultrarelativistic Quantum Molecular Dynamics,UrQMD[15],a microscopic hadronic trans-port model.The charmonium nucleon cross sections employed here are calculated in a nonrelativistic potential model[16]since at SPS energies,charmonium-nucleon interactions are predominantly nonperturbative.The charmonium precursors are not eigenstates of the QCD Hamiltonian,therefore their eﬀective sizes and interaction cross sections may vary from their production to theﬁnal state formation[16].Thus the charmonium absorption cross sections are assumed to expand linearly with time until their asymptotic value is reached. Since the produced particles in the collision have a non-thermal distribution[17],comover interactions can rather eﬀectively dissociate the J/ψ.Because of abundant high mass res-onances,most of the meson induced J/ψdissociation processes are exothermic[17].They account for an important fraction of the observed suppression,larger in Pb+Pb collisions than the nuclear absorption alone.II.THE MODELWe apply perturbative QCD to the production of charmonium states by simulating nucleus-nucleus collisions in the impulse approximation.The nuclear dependence of parton distribution functions is neglected.The resulting space-time distribution of charmonium production points is inserted into the evolving hadronic environment calculated with UrQMD [17]since the rare quarkonium production processes are small perturbations on the heavy ion collision2.Our model is thus designed to account for partonic and hadronic aspects of the charmonium dynamics.The space-time distributions of hard and soft processes,i.e.in particular charmonium production and absorption,may overlap.Thus,in our model,a charmonium state produced in a hard process can be dissociated by the interaction with a comoving hadron before this state leaves the nuclear environment and before all other hard production processes are completed(in contrast to Ref.[14]).The probability for such an event,however,is reduced due to the initially small absorption cross sections and theﬁnite formation times of comoving mesons according to the string model(see below).To avoid double counting,interactions of c¯c states with produced hadrons in individual NN collisions are excluded.In AB collisions,all hard NN collisions can contribute to the c¯c production while all soft NN collisions can contribute to the hadronic environment in which the c¯c state may be dissociated.The error imposed by this concept—inherent to all microscopic and analytical models of comover absorption—is estimated to be very small.The charmonium states are distributed according to their assumed production probability times their decay probability to J/ψ’s.Thus40%of theﬁnal states areχ’s,55%are J/ψ’s, and5%areψ′s[18].According to the spin degeneracy,1/3of theχ’s areχc10states and 2/3areχc11states.Their momenta are assigned according to the parametrization[19],dσEσiFor this study,we have slightly modiﬁed the angular distributions of meson-baryon inter-action in the UrQMD1.0model since their strong forward peak underpredicts the total pro-duced transverse energy[21].The model now reproduces the E T spectra in S(200GeV)+Au and Pb(160GeV)+Pb collisions measured by NA35and NA49,respectively[22].Neither the amount of baryon stopping nor the rapidity distribution of negatively charged parti-cles which have been shown to agree with experimental pp and AB interactions[15]are signiﬁcantly aﬀected by this modiﬁcation.III.RESULTS AND DISCUSSIONFigure1shows the calculated number of Drell-Yan muon pairs,proportional to the num-ber of hard collisions,in Pb+Pb collisions as a function of the produced neutral transverse energy within1.1<η<2.3.The NA50data[23]have been included with the abscissa rescaled to reﬂect the latest change in data[4]which indicates an≈20%shift in the abso-lute E T scale from previous publications[3,23].We are aware that the new analysis does not imply a simple overall rescaling of the old data points.However,in order to reasonably com-pare the gross features of the experimental dimuon E T spectrum with our model calculation, we have multiplied all E T-values of the data by0.8.This factor was obtained by comparing the E T−E ZDC contour from Quark Matter’97[23]and the Moriond’98[4]proceedings. The agreement between the model and the rescaled data is to be expected since the NA49 E T distribution[24]is described correctly[22]3.The additional simulation is a simple and well understood model of hard scattering processes in nucleus-nucleus collisions.Figure2shows the J/ψproduction cross section according to UrQMD calculations for several projectile-target combinations(p(450GeV)+C,p(200GeV)+Cu,p(200GeV)+W, p(200GeV)+U,S(200GeV)+U,and Pb(160GeV)+Pb)in comparison to experimental data[3].The results of the calculations are normalized to the experimental cross section in p(200GeV)+p interactions.The450GeV and160GeV simulations are rescaled to p lab=200GeV with the parametrization of Ref.[26],as done by NA50[2,3].Considering only nuclear dissociation results in a far smaller J/ψsuppression than seen in the data,not only for Pb+Pb collisions but also for S+U and even pA reactions.Note that the system-atics of nuclear absorption shown in Fig.2does not reﬂect a universal straight line as in Glauber calculations with constant absorption cross sections.By taking the nonequilibrium charmonium-meson interactions into account,good agreement with the data is obtained. However,a strong dependence on parameters such as the charmonium and comover forma-tion times and the dissociation cross sections remains to be studied in detail[20].Due to the linear expansion of the charmonium cross sections with time,the J/ψandψ′cross sections are similar in the very early stages,leading to a weak A-dependence of theψ′/J/ψratio in pA collisions at central rapidities,apparently consistent with the data. However,for a deeper understanding of this ratio quantum interference eﬀects[27]as well as refeeding processes,πJ/ψ→ψ′π[28,29],must be considered.Theψ′/J/ψratio will be studied further later[20].Figure3shows the J/ψto Drell-Yan ratio as a function of E T for Pb+Pb interactions at160GeV compared to the NA50data[4].The normalization of Bµµσ(J/ψ)/σ(DY)=46 in pp interactions at200GeV has beenﬁt to S+U data within a geometrical model[5].The application of this value to our analysis is not arbitrary:the model of Ref.[5]renders the identical E T-integrated J/ψsurvival probability,S=0.49,as the UrQMD calculation for this system.An additional factor of1.25[8]has been applied to the Pb+Pb calculation in order to account for the lower energy,160GeV,since the J/ψand Drell-Yan cross sections have diﬀerent energy and isospin dependencies.The gross features of the E T dependence of the J/ψto Drell-Yan ratio are reasonably well described by the model calculation.No discontinuities in the shape of the ratio as a function of E T are predicted by the simulation.IV.CONCLUSIONWe have examined charmonium production and absorption processes in pA and AB collisions at SPS energies.The microscopic simulation of hard processes in the impulse approximation and the hadronic transport description of AB collisions with the UrQMD model simultaneously provide reasonable E T dependencies of the Drell-Yan rates as well as baryon and meson rapidity distributions.We have modelled J/ψabsorption according to the scenario described in Ref.[16].Cross sections evolving from color transparent small conﬁgurations to asymptotic states derived from quantum diﬀusion and the dynamicalχpolarization(colorﬁltering)are taken into account.The calculated J/ψproduction cross sections for minimum bias pA,S+U and Pb+Pb collisions agree with experiment.Dissociation by nonequilibrium comovers accounts for about half of the total absorption in S+U and Pb+Pb reactions.The contribution of the interaction with comovers in pA reactions is small but not negligible.The suppression of charmonium states is sensitive to the comover momentum distributions.The eﬀective dissociation by comovers seems to indicate a nonequilibrated hadronic environment.The observed E T dependence of the J/ψto Drell-Yan ratio in Pb+Pb collisions is reproduced by the model.The calculated result is smooth,without abrupt discontinuities,in agree-ment with new high statistics data[30].We conclude that within our model,the data on charmonium cross sections at the SPS can be explained without invoking exotic mechanisms.FIGURESE T (GeV)d N /d E T (1/G e V )FIG.1.Number of Drell-Yan pairs in Pb+Pb interactions as a function of the neutral trans-verse energy within 1.1<η<2.3.The calculation is normalized to the data.Shown is the UrQMD result and experimental data from NA50[23]with the E T of the data rescaled by 0.8.The modiﬁcation is motivated by a comparison of the recently published E T −E ZDC contour plot[4]with the previously published analysis [3,23].AB467910024B (J /)/(A B )(n b /n u c l e o n )FIG.2.J/ψ-production cross sections times dimuon branching ratio in the kinematical domain 0<y cm <1and |cos θCS |<0.5,and rescaled,if necessary,to p lab =200GeV as a function of AB .The data (open triangles)are from [3].Open circles denote the production cross sections if only nuclear absorption is considered.E T (GeV)01020304050B (J /)/(D Y )FIG.3.The ratio of J/ψto Drell-Yan production as a function of E T for Pb+Pb at 160GeV.The experimental data are from Ref.[4].The normalization factor,from pp interactions at 200GeV,B µµσ(J/ψ)/σ(DY)=46is taken from Ref.[5].This value,however,has been indirectly determined in the framework of a diﬀerent model.An additional factor of 1.25[8]has been applied to the Pb+Pb calculation in order to account for the lower energy.Note that no scaling factor has been applied to the x -axis for either the calculations or the data.REFERENCES[1]C.Baglin et al.(NA38Collab.),Phys.Lett.B251(1990)472;Phys.Lett.B270(1991)105;Phys.Let t.B345(1995)617.[2]M.Gonin et al.(NA50Collab.),Nucl.Phys.A610(1996)404c.[3]M.C.Abreu et al.(NA50Collab.),Phys.Lett.B410(1997)327,337.[4]A.Romana(NA50Collab.),in Proceedings of the XXXIIIrd Rencontres de Moriond,March1998,Les Arcs,France.[5]D.Kharzeev,C.Lourenco,M.Nardi and H.Satz,Z.Phys.C74(1997)307.[6]C.-Y.Wong,Presented at the Workshop on Quarkonium Production in RelativisticNuclear Collisions,Seattle,May1998,hep-ph/9809497.[7]R.Vogt,Phys.Lett.B430(1998)15.[8]R.Vogt,LBNL-41758,Phys.Rep.in press.[9]D.Kharzeev,in Proceedings of Quark Matter’97,Tsukuba,Japan,nucl-th/9802037.[10]B.M¨u ller,DUKE-TH-98-145,Talk given at the CERN Heavy Ion Forum,June1997,nucl-th/9806023.[11]W.Cassing and C.M.Ko,Phys.Lett.B396(1997)39.[12]W.Cassing and E.L.Bratkovskaya,Nucl.Phys.A623(1997)570.[13]J.Geiss,C.Greiner,E.L.Bratkovskaya,W.Cassing and U.Mosel,nucl-th/9803008.[14]D.E.Kahana and S.H.Kahana,nucl-th/9808025.[15]S.A.Bass et al.,Prog.Part.Nucl.Phys.41(1998)225,nucl-th/9803035.[16]L.Gerland,L.Frankfurt,M.Strikman,H.St¨o cker and W.Greiner,Phys.Rev.Lett.81(1998)762.[17]C.Spieles,R.Vogt,L.Gerland,S.A.Bass,M.Bleicher,H.St¨o cker and W.Greiner,LBNL-42280,hep-ph/9809441.[18]R.Gavai,D.Kharzeev,H.Satz,G.A.Schuler,K.Sridhar and R.Vogt,Int.J.Mod.Phys.A10(1995)3043.[19]R.Vogt,Atomic Data and Nuclear Data Tables50(1992)343.[20]C.Spieles,R.Vogt,S.A.Bass,M.Bleicher and H.St¨o cker,in preparation.[21]M.Bleicher,C.Spieles,C.Ernst,L.Gerland,S.Soﬀ,H.St¨o cker,W.Greiner andS.A.Bass,hep-ph/9803346,subm.to Phys.Lett.B.[22]C.Spieles,R.Vogt,S.A.Bass,M.Bleicher,H.St¨o cker,LBNL-42380.[23]L.Ramello(NA50Collab.),in Proceedings of Quark Matter’97,Tsukuba,Japan,1997.[24]T.Alber et al.,Phys.Rev.Lett.75(1995)3814.[25]A.Borhani(NA38Collab.),Ph.D.thesis,Ecole Polytechnique,Palaiseau(1996).[26]G.A.Schuler,CERN Preprint,CERN-TH-7170-94,hep-ph/9403387.[27]L.Frankfurt and M.Strikman,Prog.Part.Nucl.Phys.27(1991)135,J.H¨u fner and B.Z.Kopeliovich,Phys.Rev.Lett.76(1996)192.[28]H.Sorge,E.Shuryak and I.Zahed,Phys.Rev.Lett.79(1997)2775.[29]J.-W.Chen and M.Savage,Phys.Rev.D57(1998)2837.[30]L.Kluberg(NA50Collab.),Proceedings of the Conference on Heavy Ion Collisions fromNuclear to Quark Matter,September1998,Erice,Italy.。

品质英语之四

品质英语之四S-ZSample,样本Sampleregressioncoefficient,样本回归系数Sample size,样本量Samplestandarddeviation,样本标准差Samplingerror,抽样误差SAS(Statisticalanalysissystem),SAS统计软件包Scale,尺度/量表Scatterdiagram,散点图Schematicplot,示意图/简图Scoretest,计分检验Screening,筛检SEASON,季节分析Secondderivative,二阶导数Secondprincipalcomponent,第二主成分SEM(Structuralequationmodeling),结构化方程模型Semi-logarithmicgraph,半对数图Semi-logarithmicpaper,半对数格纸Sensitivitycurve,敏感度曲线Sequentialanalysis,贯序分析Sequentialdataset,顺序数据集Sequentialdesign,贯序设计Sequentialmethod,贯序法Sequentialtest,贯序检验法Serialtests,系列试验Short-cutmethod,简捷法Sigmoidcurve,S形曲线Signfunction,正负号函数Signtest,符号检验Signedrank,符号秩Significancetest,显著性检验Significantfigure,有效数字Simpleclustersampling,简单整群抽样Simplecorrelation,简单相关Simplerandomsampling,简单随机抽样Simpleregression,简单回归simpletable,简单表Sineestimator,正弦估计量Single-valuedestimate,单值估计Singularmatrix,奇异矩阵Skeweddistribution,偏斜分布Skewness,偏度Slashdistribution,斜线分布Slope,斜率Smirnovtest,斯米尔诺夫检验Sourceofvariation,变异来源Spearmanrankcorrelation,斯皮尔曼等级相关Specificfactor,特殊因子Specificfactorvariance,特殊因子方差Spectra,频谱Sphericaldistribution,球型正态分布Spread,展布SPSS(Statisticalpackageforthesocialscience),SPSS统计软件包Spuriouscorrelation,假性相关Squareroottransformation,平方根变换Stabilizingvariance,稳定方差Standarddeviation,标准差Standarderror,标准误Standarderrorofdifference,差别的标准误Standarderrorofestimate,标准估计误差Standarderrorofrate,率的标准误Standardnormaldistribution,标准正态分布Standardization,标准化Startingvalue,起始值Statistic,统计量Statisticalcontrol,统计控制Statisticalgraph,统计图Statisticalinference,统计推断Statisticaltable,统计表Steepestdescent,最速下降法Stemandleafdisplay,茎叶图Stepfactor,步长因子Stepwiseregression,逐步回归Storage,存Strata,层（复数）Stratifiedsampling,分层抽样Stratifiedsampling,分层抽样Strength,强度Stringency,严密性Structuralrelationship,结构关系Studentizedresidual,学生化残差/t化残差Sub-classnumbers,次级组含量Subdividing,分割Sufficientstatistic,充分统计量Sumofproducts,积和Sumofsquares,离差平方和Sumofsquaresaboutregression,回归平方和Sumofsquaresbetweengroups,组间平方和Sumofsquaresofpartialregression,偏回归平方和Sureevent,必然事件Survey,调查Survival,生存分析Survivalrate,生存率Suspendedrootgram,悬吊根图Symmetry,对称Systematicerror,系统误差Systematicsampling,系统抽样Tags,标签Tailarea,尾部面积Taillength,尾长Tailweight,尾重Tangentline,切线Targetdistribution,目标分布Taylorseries,泰勒级数Tendency of dispersion,离散趋势Testingofhypotheses,假设检验Theoreticalfrequency,理论频数Timeseries,时间序列Toleranceinterval,容忍区间Tolerancelowerlimit,容忍下限Toleranceupperlimit,容忍上限Torsion,扰率Totalsumofsquare,总平方和Totalvariation,总变异Transformation,转换Treatment,处理Trend,趋势Trendofpercentage,百分比趋势Trial,试验Trialanderrormethod,试错法Tuningconstant,细调常数Twosidedtest,双向检验Two-stageleastsquares,二阶最小平方Two-stagesampling,二阶段抽样Two-tailedtest,双侧检验Two-wayanalysisofvariance,双因素方差分析Two-waytable,双向表TypeIerror,一类错误/α错误TypeIIerror,二类错误/β错误UMVU,方差一致最小无偏估计简称Unbiasedestimate,无偏估计Unconstrainednonlinearregression,无约束非线性回归Unequalsubclassnumber,不等次级组含量Ungroupeddata,不分组资料Uniformcoordinate,均匀坐标Uniformdistribution,均匀分布Uniformlyminimumvarianceunbiasedestimate,方差一致最小无偏估计Unit,单元Unordered categories,无序分类Upperlimit,上限Upwardrank,升秩Vagueconcept,模糊概念Validity,有效性VARCOMP(Variancecomponentestimation),方差元素估计Variability,变异性Variable,变量Variance,方差Variation,变异Varimaxorthogonalrotation,方差最大正交旋转Volumeofdistribution,容积Wtest,W检验Weibulldistribution,威布尔分布Weight,权数WeightedChi-squaretest,加权卡方检验/Cochran检验Weightedlinearregressionmethod,加权直线回归Weightedmean,加权平均数Weightedmeansquare,加权平均方差Weightedsumofsquare,加权平方和Weightingcoefficient,权重系数Weightingmethod,加权法W-estimation,W估计量W-estimationoflocation,位置W估计量Width,宽度Wilcoxonpairedtest,威斯康星配对法/配对符号秩和检验Wildpoint,野点/狂点Wildvalue,野值/狂值Winsorizedmean,缩尾均值Withdraw,失访Youden'sindex,尤登指数Ztest,Z检验Zerocorrelation,零相关Z-transformation,Z变换。

质量机能展开

• 正確性(Correctness or Definiteness): 必須能夠證明此一演算法能够正確地解決問題。
• 有限性(Finiteness): 演算法必須在有限步驟內結束。
• 結果描述和輸出(Output)
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QFD使用工具
在實施品質機能展開時,需依靠品質屋 (House of Quality； HOQ)這項工具來輔助,其內容架構有: 1.顧客需求 2.解決方案 3.相關矩陣 4.關係矩陣 5.目標值 6.優先順序
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QFD實例運用
運用QFD步驟:
1.先藉由訪談方式多搜集顧客需求,再將這些顧客需求做成問卷
2.問卷形式從“非常主要”到“非常不主要”分成五等份
3.計算出回收問卷中每一項顧客需求滿意度平均值
4.藉由演算法算出每一項顧客需求所佔標準權重
5.在將其導入QFD品質屋中排定其品質提昇先後順序
质量机能展开
• 顧客需求: 根據顧客聲音或意見而來
• 解決方案: 藉由企業內跨部門溝通與協調後所擬定策略
• 相關矩陣: 顯示各解決方案之間關係程度
• 關係矩陣: 顯示顧客需求與解決方案間有效程度
• 目標值: 根據演算法求得之數據
• 優先順序: 排定顧客需求主要順序,以及各項解決方案執行順序
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高尔斯华绥《品质》课件

2.下列词语中书写有误的一项是（）

A.趿拉 B.双颊
搔痒狭窄
羞怯稀薄
沁人心脾
咤异
蹙眉
怜悯
脚趾
茹毛饮血
并行不悖
答案：C。 “咤异”应为“诧异”
3．下列选项中加点成语使用正确的一项是 (

)
A．以色列《国土报》网站透露，如果以总统卡察夫的罪名成立，等待他的将是多年的囹圄生涯。但司法部门能否如期起诉，中间还有什么变化，会不会节外生枝等，都在未定之列。 B．平时比喻男人之美，就说赛潘安；比喻女人之美，就说赛西施。其实潘安、西施再美，我们也没见过，所以这种比喻虽属阳春白雪，却难让人记忆深刻，倒是山歌里的比喻虽是“农家土菜”，却让人感到清新自然记忆鲜明。 C．儿子对含辛茹苦望子成龙的父亲则只知写信要钱，其余完全置之度外。 D．如今，一种被称作网上代购的消费方式正方兴未艾，它可以让消费者通过在网上请人代购的方式买到时下最新颖最便宜的商品。
朴实负责
保守固执
品味细节关注人物命运
肖像变化
店面变化
橱窗里靴子的变化店面招牌的变化
1．肖像描写的变化：

他本人有点儿像皮革制成的人……好像在迷恋着理想；他的红胡子好像突然添上好多花白须毛了；

我所遇到的原来是他本人，但是多么苍老，多么消瘦啊；
我离去时．他是个六十岁的人，我回来时，他仿佛已经七十五岁了，显得衰老、瘦弱，不断地发抖；他变得衰老极了，看了他实在叫人难过。

2．店面的变化

先是两间店铺，后来只剩一间，最后不属于他了
3．橱窗里陈列的靴子的变化

橱窗里陈列着几双靴子；那几双常见的旧靴子已经失去了孤高的气派，挤缩在单独的橱窗里了；

Sunnen Honing Guide

HONING GUIDEH e l p f u l T i p s F o r S o l v i n g B o r e S i z i n g & F i n i s h i n g P r o b l e msPRINTED IN U.S.A. 0410©COPYRIGHT SUNNEN ®PRODUCTS COMPANY 2004, ALL RIGHTS RESERVED X-SP-5061PSUNNEN PRODUCTS COMPANY7910 Manchester Ave., St. Louis, MO 63143 U.S.A.Phone: 314-781-2100 Fax: 314-781-2268U.S.A. Toll-Free Sales and Service –Automotive: 1-800-772-2878 • Industrial: 1-800-325-3670International Division Fax: 314-781-6128 e-mail:*****************GENERAL HONE CORP (A Sunnen Company)471 US 250 East, Ashland, OH 44805 U.S.A.Phone:419-289-3000 Fax: 419-281-0700U.S.A. Toll-Free Sales and Service: 1-800-837-1999SUNNEN PRODUCTS LIMITED No. 1 Centro, Maxted RoadHemel Hempstead, Herts HP2 7EF ENGLANDPhone:++ 44 1442 39 39 39 Fax: ++ 44 1442 39 12 12SUNNEN AG Fabrikstrasse 18586 Ennetaach-Erlen, SwitzerlandPhone:++ 41 71 649 33 33 Fax: ++ 41 71 649 34 34Sunnen®reserves the right to change or revise specifications and product design in connection with any feature of our products contained herein. Such changes do not entitle the buyer to corresponding changes,improvements, additions, or replacements for equipment, supplies or accessories previously sold. Information contained herein is considered to be accurate based on available information at the time of printing.Should any discrepancy of information arise,Sunnen recommends that user verify discrepancy with Sunnen before proceeding.SHANGHAI SUNNEN MECHANICAL CO., LTD.889 Kang Qiao East Road, PuDong Shanghai 201319, P.R. ChinaPhone:86 21 5 813 3322 Fax: 86 21 5 813 2299SUNNEN ITALIA S.R.L.Viale Stelvio 12/1520021 Ospiate di Bollate (MI) ItalyPhone:39 02 383 417 1 Fax: 39 02 383 417 50“SUNNEN AND THE SUNNEN LOGO ARE REGISTERED TRADEMARKS OF SUNNEN PRODUCTS COMPANY.”Standard Sunnen Tooling and Procedures will satisfy all ordinary honing requirements. If problems are encountered, they can usually be solved by following procedure suggested below. For detailed information on difficult or unusual honing problems contact your local Sunnen Field Engineer or Sunnen Customer Service Department in St. Louis, Missouri, USA.CONDITION TO BE CORRECTED STEP1STEP2STEP3STEP4STEP5STONE GLAZED*Sharpen A or J stone Increase cutting Increase stroking Use a softer stone Check oil to be STONE Stone surface looks with MAN-700pressure speed(one with a lower sure you are using NOT clean but cutting diamond dresser; use hardness number)Sunnen Industrial CUTTING grains are dulledLBN-700 dressing stick Honing Oil*on all other stones (Honing dial STONE LOADED*Clean stone with Increase stroking Use a softer stone Use a coarser grit Check oil to be needle moves Stone surface looks LBN-700 dressing pressure (one with a lower stone (one with a sure you are using too slowly)smeared and stickhardness number)lower grit number)Sunnen Industrial clogged with chipsHoning Oil*SLOW STOCK REMOVAL*Increase spindle speedIncrease cutting Check oil to be Use a softer stone Use a coarser grit (Honing dial needle moves too slowly)pressuresure you arc using (one with a Lower stone (one with a Sunnen Industrial hardness number)lower grit number)Honing Oil*POOR STONE LIFE* Decrease cutting Use faster spindle Use harder stone Use coarser grit stone Using Sunnen (Honing dial needle moves too fast)pressur e spe ed (higher hardness number) (lower g rit number) Industrial Honing Oil/Coolant*BELLMOUTH True stone and shoes Use softer stone If Bore is LONGERShorten STONE only If bellmouth persists with truing sleeve (OK with lower than 2/3 stone length:(or row of stones)shorten stones still If part is short or hardness number)slightly on both ends more but do not shorten unbalanced, shorten shoes any further stroke length If Bore is SHORTER Shorten STONES and CAUTION:than 2/3 stone length:SHOES equally to Overcorrection of1-1/2 times bore bellmouth will lead length to barrel conditionBARREL True stone and shoes Use finer grit stone Use longer stone or Use mandrel with CAUTION:with truing sleeve (one with higher grit shorten guide shoes longer stone and shoe Overcorrection ofnumber)on both ends barrel will leadto bellmouth conditionTAPER IN True stone and shoes Change stroke so tight Reverse work on If power stroking, make OPEN HOLE with truing sleeveend of bore is stroked mandrel more oftensure spindle and stroker over stone further are in alignment TAPER IN Shorten stone and True stone and shoes If hole has insufficient Provide sufficient Provide adequate oil BLIND HOLE shoes to about 3/4frequently with truing or no relief at bottom,relief at bottom of flow at bottom of hole shorten stone more sleeveuse hard tip stone holeto wash cutting out if taper persists OUT-OF-ROUNDMake sure honing Thoroughly true stone If thin wall part,If stone stops cutting If power stroking tool is recommended and shoes to exact decrease cutting at decreased pressure make sure spindle size for diameter to hole diameter pressure use stone with lower and stroker are in be honedhardness numberalignmentWAVINESS Use honing tool with sufficient stone length to bridge waviness (or Iands and ports in bore)RAINBOWUse L, BL, or multi-stone mandrel. Stone Use shorter stroke Use stone with lower length should be at least 1-1/2 times the length hardness number to length of bore for best bow correction (less overstroke)avoid part flexing FINISH TOO ROUGH*Decrease cutting Use finer grit stone Check oil to be sure Thoroughly true shoes For extremely fine pressure(one with higher grit you are using Sunnen to exact hole diameterfinishes in soft or number)Industrial Honing Oil*exotic material, use bronze mandrel or bronze shoes RANDOM SCRATCHESDecrease cutting Use finer grit stone Use softer stone If hard steel mandrel is Check oil to be pressure(one with higher grit (one with lower being used, change to sure you are using number)hardness number)soft steel mandrel. If Sunnen Industrial soft steel mandrel or Honing Oil*shoes are being used,change to bronze mandrel or shoes*Many honing problems, such as poor cutting action, poor stone life, and rough finish are caused by wrong honing oil, insufficient honing oil, dirty honing oil, or contaminated honing oil. Use only clean, full-strength Sunnen Industrial Honing Oil. Make sure that honing oil is neither diluted or "cut" with other oils. Keep solvents and cleaning fluids away from honing machine.{{FOR FAST STOCK REMOVAL IN DE-BURRED, BORED, REAMED OR GROUND HOLESFOR FINE FINISHING SOFT STEELHARDENED STEELIN PREVIOUSLHONED HOLES DIAMETER HONING FOR INCLUDIES: CAST STEELS HARD SOFT STEEL,SPINDLE OF BOREUNITDE-BURRING & STAINLESS STEELS FOR OCCASIONALFOR SOFT CAST IRON,CARBIDE GLASSS STEEL,BRONZE,CARBIDE,GLASSSPEED IN ROUGH (USE BRONZE MANDREL WORKPRODUCTION BRASSBRONZE &SOFT ALUMINUM CERAMICRPM HOLESOR SHOES IN WORK RUNS&CERAMIC * * *BRASSCAST IRON(MAX)STAINLESS STEEL)ALUMINUM * * *ALL FOR FOR TRY THIS IF FIRSTCHOICE MATERIALS OCCASIONALPRODUCTION STONE DOES NOT CUT,* *!!mm INCHES WORK WORK FIRST USE THIS STONE1,52- 2,03(0.060-0.080)D2D6-A67D6-A67D6-NM69D6-A65D6-A63D6-NM69D6-J63D6-J67D6-DM57D6-DM57D6-J93D6-J95D6-DR07D6-DR0730002,03- 2,54(0.080-0.100)D2D8-A67D8-A67D8-NM69D8-A65D8-A63D8-NM69D8-J63D8-J67D8-DM57D8-DM57D8-J93D8-J95D8-DR07D8-DR0730002,54- 3,05(0.100-0.120)K3K3-A611K3-A67K3-NM69K3-A65K3-A63K3-NM69K3-J63K3-J67K3-DM57K3-DM57K3-J93K3-J95K3-DMO7K3-DMO73000BU L3-A611L3-A67L3-NM69L3-A65L3-A63L3-NM69L3-J63L3-J67L3-DM57L3-DM57L3-J93L3-J95L3-DMO7L3-DMO73,05- 3,81(0.120-0.150)K4K4-A611K4-A67K4-NM69K4-A65K4-A63K4-NM69K4-J63K4-J67K4-DM57K4-DM57K4-J93K4-J95K4-DMO7K4-DMO73000BL4L4-A611L4-A67L4-NM69L4-A65L4-A63L4-NM69L4-J63L4-J67L4-DM57L4-DM57L4-J93L4-J95L4-DMO7L4-DMO73,81- 4,70(0.150-0.185)K5K5-A611K5-A67K5-NM69K5-A65K5-A63K5-NM69K5-J63K5-J57K5-DM57K5-DM57K5-J93K5-J95K5-DMO7K5-DMO73000BL5L5-A611L5-A67L5-NM69L5-A65L5-A63L5-NM69L5-J63L5-J57L5-DM57L5-DM57L5-J93L5-J95L5-DMO7L5-DMO74,70- 6,22(0.185-0.245)K6, JK6K6-A415K6-A57K6-NM69K6-A55K6-A63K6-NM69K6-J63K6-J57K6-DM57K6-DM57K6-J93K6-J95K6-DMO7K6-DMO73000L6, BL6L6-A413L6-A57L6-NM69L6-A55L6-A63L6-NM69L6-J63L6-J57L6-DM57L6-DM57L6-J93L6-J95L6-DMO7L6-DMO7K8, JK8K8-A413K8-A57K8-NM55K8-A55K8-A63K8-NM55K8-J63K8-J57K8-DM55K8-DM55K8-J93K8-J95K8-DMO5K8-DM056,22- 7,82(0.245-0.308)L8, BLS L8-A413L8-A57L8-NM55L8-A55L8-A63L8-NM55L8-J63L8-J57L8-DM55L8-DM55L8-J93L8-J95L8-DM05L8-DMO53000Y8Y8-A49Y8-A57'Y8-A55Y8-A63*Y8-J63Y8-J57****Y8-J93Y8-J95****K10, JK10K10-A413K10-A57K10-NM55K10-A55K10-A63K10-NM55K10-J63K10-J57K10-DM55K10-DM55K10-J93K10-J95K10-DM05K10-DMO57,82- 9,40(0.308-0.370)L10, BL10L10-A413L10-A57L10-NM55L10-A55L10-A63L10-NM55L10-J63L10-J57L10-DM55L10-DM55L10-J93L10-J95L10-DM05L10-DMO52000Y10Y10-A49Y10-A57*Y10-A55Y10-A63*Y10-J63Y10-J57****Y10-J93Y10-J95****K12, JK12K12-A413K12-A57K12-NM55K12-A55K12-A63K12-NM55K12-J63K12-J57K12-DM55K12-DM55K12-J93K12-J95K12-DM05K12-DMO516009,40- 12,57(0.370-0.495)L12, BL12L12-A413L12-A57L12-NM55L12-A55L12-A63L12-NM55L12-J63L12-J57L12-DM55L12-DM55L12-J93L12-J95L12-DMO5L12-DMO5to Y12Y12-A49Y12-A57*Y12-A55Y12-A63*Y12-J63Y12-J57****Y12-J93Y12-J95****2000K16, JK16K16-A413K16-A57K16-NM55K16-A55K16-A63K16-NM55K16-J63K16-J57K16-DM55K16-DM55K16-J93K16-J95K16-DMO5K16-DMO512,57- 15,72(0.495-0.619)L16, BL16L16-A413L16-A57L16-NM55L16-A55L16-A63L16-NM55L16-J63L16-J57L16-DM55L16-DM55L16-J93L16-J95L16-DMO5L16-DMO51270Y16Y16-A49Y16-A57"Y16-A55Y16-A63*Y16-J63Y16-J57**Y16-J93Y16-J95K20, JK20K20-A413K20-A57K20-NM55K20-A55K20-A63K20-NM55K20-J63K20-J57K20-DM55K20-DM55K20-J93K20-J95K20-DMO5K20-DMO515,72- 18,90(0.619-0.744)L20, BL20L20-A413L20-A57L20-NM55L20-A55L20-A63L20-NM55L20-J63L20-J57L20-DM55L20-DM55L20-J93L20-J95L20-DMO5L20-DMO51000P20P20-A413P20-A57P20-NM55P20-A55P20-A63P20-NM55P20-J63P20-J57P20-DM55P20-DM55P20-J93P20-J95P20-DMO5P20-DMO5Y20Y20-A411Y20-A57Y20-A55Y20-A63*Y20-J63Y20-J57""**Y20-J93Y20-J95AK20, JAK20K20-A413K20-A57K20-NM55K20-A55K20-A63K20-NM55K20-J63K20-J57K20-DM55K20-DM55K20-J93K20-J95K20-DMO518,90- 25,40(0.744-1.00)AL20, BAL20L20-A413L20-A57L20-NM55L20-A55L20-A63L20-NM55L20-J63L20-J57L20-DM55L20-DM55L20-J93L20-J95L20-OM05800P20P20-A413P20-A57P20-NM55P20-A55P20-A63P20-NM55P20-J63P20-J57P20-DM55P20-DM55P20-J93P20-J95P20-DMO5AAY20N20Y20-A411Y20-A57*Y20-A55Y20-A63*Y20-J63Y20-J57****Y20-J93Y20-J95**AK20, JAK20K20-A413K20-A57K20-NM55K20-A55K20-A63K20-NM55K20-J63K20-J57K20-DM55K20-DM55K20-J93K20-J95K20-DM05K20-DMO525,40- 26,19(1.000-1.031)AL20, BAL20L20-A413L20-A57L20-NM55L20-A55L20-A63L20-NM55L20-J63L20-J57L20-DM55L20-DM55L20-J93L20-J95L20-DMO5L20-DMO5640P28P28-A413P28-A57P28-NM55P28-A55P28-A63P28-NM55P28-J63P28-J57P28-DM55P28-DM55P20-J93P20-J95P20-DMO5P20-DMO5R28R28-A413R28-A57R28-NM55R28-A55R28-A63R28-NM55R28-J63R28-J57R28-DM55R28-DM55Y20-J93Y20-J95..AK20K20-A413K20-A57K20-NM55K20-A55K20-A63K20-NM55K20-J63K20-J57K20-DM55K20-DM55K20-J93K20-J95K20-DMO5K20-DMO526,19- 31,75(1.031-1.250)P28P28-A413P28-A57P28-NM55P28-A55P28-A63P28-NM55P28-J63P28-J57P28-DM55P28-DM55L20-J93L20-J95L20-DMO5L20-DMO5640R28R28-A413R28-A57R28-NM55R28-A55R28-A63R28-NM55R28-J63R28-J57R28-DM55R28-DM55P28-J93P28-J95P28-DMO5P28-DMO531,75- 92,08(1.250-3.625)P28P28-A413P28-A57P28-NM55P28-A55P28-A63P28-NM55P28-J63P28-J57P28-DM55P28-DM55P28-J93P8-J95P28-DMO5P28-DMO5640 to R28R28-A413R28-A57R28-NM55R28-A55R28-A63R28-NM55R28-J63R28-J57R28-DM55R28-DM55R28-J93R8-J95R28-DMO5R28-DMO550092,08-152,40(3.625-6.000)P28P28-A413P28-A57P28-NM55P28-A55P28-A63P28-NM55P28-J63P28-J57P28-DM55P28-DM55P28-J93P28-J95P28-DMO5P28-DMO5200R28R28-A413R28-A57R28-NM55R28-A55R28-A63R28-NM55R28-J63R28-J57R28-DM55R28-DM55R28-J93R28-J95R28-DMO5R28-DM0525,20- 34,93(0.992-1.375)Y32Y32-A49Y32-A57*Y32-A55Y32-A63*Y32-J63Y32-J57****Y32-J93Y32-J95****640 to 50034,67- 44,45(1.365-1.750)Y44Y44-A49Y44-A57*Y44-A55Y44-A63*Y44-J63Y44-J57****Y44-J93Y44-J95****500 to 40044,20- 57,15(1.740-2.250)Y56Y56-A49Y56-A57*Y56-A55Y56-A63*Y56-J63Y56-J57****Y56-J93Y56-J95****400 to 32056,90- 69,85(2.240-2.750)Y72Y72-A49Y72-A57*Y72-A55Y72-A63*Y72-J63Y72-J57****Y72-J93Y72-J95****320 to 25069,60- 82,55(2.740-3.250)Y88Y88-A49Y88-A57*Y88-A55Y88-A63*Y88-J63Y88-J57****Y88-J93Y88-J95****25082,30- 98,42(3.240-3.875)Y104Y104-A49Y104-A57*Y104-A55Y104-A63*Y104-J63Y104-J57****Y104-J93Y104-J95****20063,50- 68,58(2.500-2.700)AN-600G25-A47G25-A45*G25-A45G25-A63*G25-J63G25-J45G25-DV57G25-DV57G25-J85G25-J87G25-DV87**G25-DV87**25068,58-104,14(2.700-4.100)AN-600M27-A47M27-A45*M27-A45M27-A63*M27-J63M27-J45M27-DV57M27-DV57M27-J85M27-J87M27-DV87**M27-DV87**20088,90-139,70(3.500-5.500)AN-600N37-A47N37-A45*N37-A45N37-A63*N37-J63N37-J45N37-DV57N37-DV57N37-J85N37-J87N37-DV87**N37-DV87**20063,50- 83,82(2.500-3.300)AN-600GY25-A47GY25-A45*GY25-A45GY25-A63*GY25-J45GY25-J45****GY25-J85GY25-J85****250GG25-A47GG25-A45*GG25-A45GG25-A63*GG25-J45GG25-J45****GG25-J85GG25-J85****83,82-106,68(3.300-4.200)AN-600MY33-A47MY33-A45*MY33-A45MY33-A63*MY33-J45MY33-J45****MY33-J85MY33-J85****200MM33-A47MM33-A45*MM33-A45MM33-A63*MM33-J45MM33-J45****MM33-J85MM33-J85****101,60-142,24(4.000-5.600)AN-600NY40-A47NY40-A45*NY40-A45NY40-A63*NY40-J45NY40-J45****NY40-J85NY40-J85****200NN40-A47NN40-A45*NN40-A45NN40-A63*NN40-J45NN40-J45****NN40-J85NN40-J85****ABRASIVE TYPESGRIT SIZEHARDNESSRECOMMENDED STONESGRIT SIZEMATERIAL ABRASIVE TYPE 801001502202803204005006001200HARD ALUMINUM OXIDE 25 / 0,65–20 / 0,5018 / 0,4512 / 0,3010 / 0,25 5 / 0,12 3 / 0,08 1 / 0,03–STEEL SILICON CARBIDE CBN/BORAZON ®–55 / 1,4045 / 1,1540 / 1,0028 / 0,70–20 / 0,50–7 / 0,18 2 / 0,05SOFT ALUMINUM OXIDE 80 / 2,00–35 / 0,9025 / 0,6520 / 0,5016 / 0,407 / 0,18 4 / 0,10 2 / 0,05–STEEL SILICON CARBIDE CBN/BORAZON ®–65 / 1,60–70 / 1,75––25 / 0,65–16 / 0,40 5 / 0,12CAST SILICON CARBIDE 100 / 2,50–30 / 0,7520 / 0,5012 / 0,30– 6 / 0,15 5 / 0,12 3 / 0,08–IRON DIAMOND –––80 / 2,00––50 / 1,27–20 / 0,5012 / 0,30ALUMINUM,SILICON CARBIDE 170 / 4,30–80 / 2,0055 / 1,4033 / 0,8527 / 0,7016 / 0,4012 / 0,30 2 / 0,05–BRASS, BRONZE CARBIDE DIAMOND ––30 / 0,7520 / 0,50––7 / 0,18– 3 / 0,08 1 / 0,03CERAMIC DIAMOND ––50 / 1,2740 / 1,00––20 / 0,50–15 / 0,4010 / 0,25GLASSDIAMOND––95 / 2,4070 / 1,80––30 / 0,75–15 / 0,408 / 0,20SUNNEN STONE GUIDEAPPROXIMATE SURFACE FINISH IN MICROINCHES R A / MICROMETERS (MICRONS) R A* CBN/Borazon stones available on special order. !CBN/Borazon stones available on special order. ** CBN/Borazon stones available on special order.*** CBN/Borazon stones available on special order.FINISH FIGURES BASD ON USE OF SUNNEN HONING OIL. IN GENERAL, USE OF WATER BASED COOLANTS RESULT IN FINER SURFACE FINISH AND REDUCED METAL REMOVAL RATES.A—ALUMINUM OXIDE C —SILICON JCARBIDE DM DR —DIAMONDDV NM CBN /NR —NVBORAZON1—702—803—1004—1505—2206—2807—3208—4009—5000—60090—90000—12001—SOFT2—3—5—7—11—15—HARDK8 –A57SERIES ABRASIVE GRIT HARD-TYPE SIZE NESS}}}HONING GUIDEInformation shown is applicable to (conventional) stones, which must be used with honing oil, and NM & DM stones (metal bond)which may be used with either honing oil or water based coolant. The process fluid is very important. Many honing problems,such as poor cutting action, poor stone life, and rough finish are traceable to the process fluid. In general, honing performance will be reduced when water based coolants are used.。

Five_Star_Evaluation_Program

Five-Star Chapter EvaluationTable of ContentsSection I Page # Basic Principles Guiding the University-Greek Relationship 3 Greek IdealsWhat is a Fraternity 5Complement to the Academic Mission 6Developing Leaders in Members 6Serving the Community 7Character Development 7Personal Development 8Community Building 9Life-Long Friendships 9 Section IIFive Star Chapter Evaluation Program 11 An Outline of the Program 12 Academics 13 Financial Management 15 University/Community/Alumni Relations & Service 16 Campus Involvement 18 Membership Recruitment & Member Education Program 20 Section IIISummary Form 22 University Counseling Center Workshop Topics 24 Telephone Directory 25Basic Principles Guiding the University-Greek Relationship Duquesne University has had a long and rich relationship with its collegiate fraternities and sororities. As an important component of the co-curricular programs for undergraduate students, Greek chapters have supported the central mission of the University by providing an enriched out-of-class living/learning experience. Fraternal organizations (the words "fraternal" or "fraternity" refer to both men's and women's Greek letter organizations) have existed on the Duquesne campus since the early part of the 20th century, and are characterized by a tradition of involvement and leadership in campus life.The University has been supportive of the ideals and goals of individual chapters and, collectively, a Greek community. The organizational ideals and goals promote personal development and a strong sense of identity with the institution as well as post-graduate association. The ideals and goals of fraternal life include scholarship, moral development, leadership, community service, individual and group initiative, self-governance, and an array of interpersonal and social skills development.The relationship between the University and the Greek community is one that must be mutually beneficial. Greek chapters can enhance the quality of life for students on campus by providing a full range of opportunities for meaningful individual involvement and growth. Life-long commitment to a Greek organization can in turn result in greater alumni involvement and service to the university, community, and country.The document developed by the American College Personnel Association, "The Student Learning Imperative: Implications for Student Affairs" (1994) states that the "Hallmarks of a college-educated person include: ...(b) an ability to apply knowledge to practical problems encountered in one's vocation, family, or other areas of life; (c) an understanding and appreciation of human differences; (d) practical competence skills (e.g. decision making, conflict resolution); and (e) a coherent integrated sense of identity, self-esteem, confidence, integrity, aesthetic sensibilities, and civic responsibility" (p. 1). Given the intensity of daily life and the range of developmental challenges that exist in a college setting, fraternities and sororities remain perhaps the most productive living-learning experiences available to students that will allow them to achieve these competencies.Greek students at Duquesne University are represented in a variety of leadership organizations and positions (e.g. Student Government, Resident Assistants, Orientation Advisors, Honor Societies, Campus Ministry) on campus. They are richly involved with the local community through service initiatives, and Greek alumni contribute significantly greater amounts of money to their alma mater compared to non-Greek alumni. Inter/national data reflect similar conclusions. Supporting Greek life has been an important educational initiative for the campus. Greek organizations have the potential to affect student development in powerful and lasting ways. Organizations which ultimately and cumulatively manage to promote leadership, foster scholastic excellence, encouragecommunity service, and develop life-long friendships deserve a prominent place in the University community.The American Council on Education (ACE) examined the Greek movement and published a document entitled Greek Organizations on the College Campus: Guidelines for Institutional Action (1990) which contained "an analysis, recommendations, and suggested strategies to help college and university leaders as they examine Greek systems associated with their institutions and as they decide how they can best align these organizations with the institution's education mission and values. (p. 1)" The materials included in this document are based on several of the recommendations of the ACE Report.GREEK IDEALSWhat Is a Fraternity"A fraternity is an association of men, selected in their college days by democratic processes, because of their adherence to common ideals and aspirations. Out of their association arises a personal relation which makes them unselfishly seek to advance one another in the arts of life and to add, to the formal instruction of the college curriculum, the culture and character which men acquire by contact with great personalities, or when admitted to partnership in great traditions" (Newton Baker, The Purple Pilgrim, Manual of Phi Gamma Delta).The first Greek letter organization, Phi Beta Kappa, was founded at the College of William and Mary in 1776. The fraternity was founded as a society with the purpose of openly discussing the ideas and views of the time and without the supervision of the faculty. According to Baird's Manual, the preeminent historical account and "encyclopedia" of Greek life, "Inevitably, what had begun as shared yearning for a livelier life of the mind grew into a broader fellowship. Intellectual pastimes persisted at the center of fraternity life until nearly the end of the nineteenth century: orations, debates, the reading of original poems as well as scientific and scholarly papers" (Baird's Manual, pp. I-II).The Greek organizations at Duquesne University were founded on similar principles and aspirations. Creeds extol virtues such as "to teach that true men the world over should stand together and contend for supremacy of good over evil; to teach not politics, but morals” (Alpha Tau Omega); "You ng men who join the Fraternity grow in friendship, scholarship, leadership, sportsmanship and citizenship" (Sigma Nu); "We seek the highest ideal of womanhood, and we try to gain this ideal by cultivating not only the power and passion for seeking intellec tual development but also, the spirit of love and charity." (Alpha Phi); “To crusade for justice, to seek the truth and defend it always” (Delta Zeta); "The True Gentleman is the Man whose conduct proceeds from good will and an acute sense of propriety, and whose self-control is equal to all emergencies..." (Sigma Alpha Epsilon, "The True Gentleman").Greek organization members ideally espouse to be model student citizens of the campus. Universities long have supported the Greek movement given the direct relationship between the mission of higher education and the purposes and espoused values of the college fraternity. The shared or common mission of higher education institutions and fraternal organizations is to prepare students for responsible citizenship. Inter/national Greek organizations have recognized that to be effective and valued members of the campus community, they must work in partnership with the institution. Both entities prosper when the values and principles for which Greek groups were established are realized.Complement to the Academic MissionThe promotion of good scholarship and attainment of academic excellence are essential to the purpose of the college fraternity. Working as an integral component of the academic mission, Greek organizations have sought to enrich the intellectual life of the campus by sponsoring lectures, debates, and discourse among members, faculty, and friends. All Greek organization mission statements reflect the collaborative nature of the fraternity experience with academic life. Examples include: “The object of this organization shall be to develop the highest type of womanhood through education, social life, and service to country and humanity” (Gamma Phi Beta); “I will strive for academic achievement and practice academic integrity” (#1 Basic Expectation of a Delta Chi). “To promote academic excellence and to provide assistance to persons in need” (Delta Sigma Theta). “Dedicated to academic excellence, leadership deve lopment, high ideals and sisterhood” (Alpha Gamma Delta). Clearly, Greek organizations were founded and promulgated because they embraced the academic achievement of their members.The University is, first and foremost, concerned for the academic welfare of its students. The central mission of the University is "to serve God by serving students - through commitment to excellence in liberal and professional education”. The missions of the University and Greek organizations are complementary and supportive of the intellectual growth of students.Developing Leadership in MembersDeveloping leadership skills in members, creating opportunities to practice those skills, and recognition for leadership achievements of members have always been instrumental dimensions of the fraternity's purpose. Indeed, leadership development may be the most recognized trademark of the fraternal experience given the number of leaders who have emerged from fraternity and sorority roll books. Numerous CEOs of major corporations, political leaders, professional athletes, film stars and university presidents are affiliated with Greek organizations. Members of Greek groups are present in educational, political, religious, cultural and artistic arenas.Fraternity an d sorority purposes reflect this emphasis on leadership. “The Fraternities principles are…to develop good leaders for America. Leadership is the process through which a Sig Tau shares his Brotherhood wit h other men” (Sigma Tau Gamma); “To make a differenc e in the lives of our membership by developing the potential of each individual through visionary programming which emphasizes leadership development, service to others, academic success and continued personal growth for women with a commitment to friendship and the future based on the values and traditions of our past (Zeta Tau Alpha).Most inter/national fraternities sponsor annual or bi-annual leadership schools or conventions in addition to regional workshops. These workshops provide comprehensive leadership training for student leaders and alumni advisors. Thisis evidence in the significant commitment inter/national organizations make to promote and teach leadership skills to their members.On a daily basis, Greek organization leaders are faced with decisions and challenges that test their leadership and managerial skills. These challenges have the net effect of allowing students ample opportunities to practice skills and develop competencies in leading. These leadership opportunities (managing budgets, orchestrating meetings with members, community service events, etc) are powerful learning experiences. Greek organizations are in a unique position to teach leadership skills to members and to create avenues in which to practice these abilities.Serving the CommunityThe support of philanthropic endeavors is an important aspect of developing chapters and their members. Most inter/national organizations support causes and philanthropic organizations such as breast cancer awareness (Zeta Tau Alpha), support of national organizations and local projects designated for speech and hearing help (Delta Zeta), or the Books for Kids donation collection project (Sigma Tau Gamma). Many of the historically African-American fraternities and sororities explicitly state a commitment to service efforts. "The efforts of Alpha Kappa Alpha women in the promotion of high scholarship, vocational and career guidance, health services, the advancement of human and civil rights, and in so many other areas constitute a priceless part of the American experience in the twentieth century” (Alpha Kappa Alpha). Serving others can be a powerful learning experience. The encouragement of this principle of Greek life can reap rewards for both the students and those whom they serve."There is scarcely a inter/national fraternity or sorority today which does not energetically promote a program of scholarships and awards...as well as such social welfare projects as orthopedics, muscular dystrophy, the deaf...and so on" (Baird's Manual, pp. I-19). Greek organizations have embraced one of the most positive teaching methodologies - education through service learning.Character Development“High ideals and high moral and ethical teachings are central to the theme of most rituals...The new member is instructed as to the high purposes of the group and of the responsibility which membership requires" (Baird's Manual, pp. I-13). Fraternity rituals are filled with words such as honor, trust, respect, humility, courage, and tolerance. Central to the mission of the fraternity is the creation of individuals who learn about responsibility, to others and to self.Greek organizations promote values such as "to stand together and contend for supremacy of good over evil; to teach, not politics, but morals; to foster, not partisanship, but the recognition of true merit wherever found” (Alpha Tau Omega); "to obey God’s principles of justice and right” (Purpose of Alpha Phi); and “to foster and develop the highest and noblest traits of man” (Alpha Phi Delt a). They seek to develop in their members’ character beyond reproach andan understanding of humankind. They espouse a philosophy of open-mindedness toward others. Unanimous agreement could be obtained from its leaders that the Greek experience has as one of its fundamental purposes the development of men and women of the highest and most noble character. The campus community along with inter/national fraternity officers and alumni expects students to not only espouse these values but to practice them in their daily lives. College fraternities and sororities place high value on educating student members on the rights and responsibilities associated with being a citizen of their local and global communities. From helping those in need to respecting the rights and dignity of others, Greek organizations foster the character development of individual members.Personal DevelopmentGreek organizations provide numerous avenues to promote the personal and social development of their members. Students learn interpersonal communication skills by participating in membership recruitment events; learning to associate and live with other members for three or four years; and interacting with alumni, inter/national organization representatives, and University faculty and staff. Members learn conflict resolution skills by having to adapt to roommates who are brothers or sisters. Chapter members learn time management skills as they juggle their academic commitments with their fraternal experience, work, and relationships.“It's about pledging our efforts to our communities to make them better places and our energies to our futures. It's about committing ourselves to each other and the ideals of Alpha Sigma Tau. Facing life's challenges and working together as sisters, we learn to develop, in each other, strengths and positive values” (Alpha Sigma Tau). “…was founded on religious beliefs and is the foundation of our principles, value system and ideals. To deepen the spiritual and enrich the temporal lives of our members through a well-balanced program of fraternal, spiritual, intellectual, social and service activities” (Phi Kappa Theta). There are many ways Greek organizations assist in the development of their members. Proof comes from the numerous testimonies from alumni who reflect on their Greek affiliation and realize the positive difference it made in their professional and personal lives. This significant out-of-class endeavor provides ample opportunities for an enriched college experience.Community BuildingGreek organizations are structured as small communities within the larger campus community. Governing bodies promote collaboration and self-governance among the member groups. Common traditions such as Homecoming, Greek Week and Carnival bind the community together for a common good and a festive experience. By nature, Greek organizationscontribute to the social fabric of the campus community and have elaborate mechanisms for involving members in campus activities.The Pan-Hellenic Council groups provide a particularly important community building function within the African-American community on campus. These organizations have a rich heritage of supporting and encouraging African-American students. Alpha Phi Alpha Fraternity Inc., for example, has been active in the civil rights movement, has established a campaign to increase African-American participation in higher education, and has been active in school integration efforts.Fraternal alliances often do not end at graduation. Alumni play critical roles as mentors and volunteers for undergraduates. Alumni groups continue to serve an integral role in the day-to-day life of the chapter. Some volunteers serve as advisors, chapter corporation representatives or counselors. Most chapters provide newsletters, keeping alumni up to date on the progress of the undergraduate chapter. Inter/national organizations publish quarterly journals with extensive coverage of alumni achievements. More than virtually any other group on campus, fraternities and sororities provide a structured means by which alumni can spend a lifetime of interacting with their classmates and maintaining an effective bond to the institution. Moral and political support as well as financial contributions to their alma mater are valued outcomes of such a relationship. Greek organizations generally promote a life-long commitment to the University and serve to generate a positive attitude about the campus. Greek alumni support athletic events and activities, rally for political causes supportive of University aims, and provide significant financial assistance for achieving University goals.Life-long FriendshipsThe creation and nurturing of life-long friendships are the hardest to quantify and measure yet are powerful aspects of the fraternity culture. Fraternities and sororities play an integral role within the campus community and help new students adjust to a large and overwhelming college environment. New members find a sense of belonging within the chapter and in the Greek community. Brothers and sisters play the role of collegiate siblings while alumni advisors and other alumni leaders become mentors, counselors, and positive role models. Numerous examples of deep friendship exist within the chapter bonds. For example, each spring some chapters host final banquets and senior "send-offs" to say farewell and thank you to graduating members. Many chapters provide scholarships to outstanding members as ways of helping to pay for college costs while other chapters have recognition dinners to honor contributions their members have made to the chapter and larger community. Chapter support is even more critical when serious problems arise with members. Some examples of this type of support at Duquesne University include: a sister with a serious eating disorder is confronted by her chapter who helps her overcome her health problem, a fraternity provides meaningful emotional support to the family of abrother killed in a tragic accident; and a fraternity requires an alcoholic member to get help in order for him to continue to be involved in the chapter. These powerful chapter bonds deepen the meaning of life-long friendships.In conclusion, it is these perspectives that we establish in this document that provide a mutual understanding throughout the Greek community to assist chapters in continuously improving and evolving into successful fraternal organizations.Duquesne University of the Holy GhostFive Star Chapter Evaluation ProgramIntroductionTo improve the management and the quality of sorority and fraternity chapters at Duquesne University, the Office of the Executive Vice President for Student Life and Office of Greek Life, Honor Societies & Professional Organizations have implemented the following evaluation and awards system.The results of the evaluation will be used to designate a chapter as a Five Star, Four Star, Three Star, Two Star, or One Star chapter. Each chapter evaluation will be shared with each individual chapter and may be utilized with national and local alumni upon request and mutual agreement between both groups.The end of the year awards are determined by this document. The top three highest-scoring fraternities and sororities are in the running for the President's Cup Award for the Most Outstanding Chapter; in addition to their awards memo. Additionally, the President Cup chapters will receive a monetary incentive to be used for their local or national philanthropy.Each spring, numerous awards are also given to the fraternity and sorority with the highest grade point average, the most improved academic standing, excellence in community service & involvement, and many other areas. Greek Woman and Greek Man of the Year are some of the additional individual awards that will be given based on separate applications available in the spring semester. These awards will also be presented at the Greek Awards Banquet in April.An Outline of the ProgramThe following areas will receive an evaluation each year:1. Scholarship - 25%2. Financial Management - 10%3. Risk Management - 10%4. University Mission, Community, & Alumni Relations - 15%5. Philanthropy & Service - 10%6. Campus Involvement - 10%7. Member Development - 10%8. Membership Intake and New Member Education - 10% Total Points Possible:1000 pointsBonus Points:Throughout the course of the year, several opportunities for bonus points will arise at events sponsored through the Office of Greek Life. Information regarding how to obtain these points will be distributed before the event takes place.Scoring Criteria:90% or higher of points possible = Five Star status80% - 89% of points possible = Four Star status70% - 79% of points possible = Three Star status60% - 69% of points possible = Two Star status50% - 59% of points possible = One Star statusBelow 50% of points possible = Zero Stars / organizational reviewThe intent of the Five Star Chapter evaluation is to provide a framework by which chapters can quantify and document their activities and successes, while creating a tool by which fraternities and sororities can be evaluated. There is an expectation that all chapters will strive to attain a Five Star rating and that the Greek Community at Duquesne University will be an example of excellence to other Greek Communities nationwide.Recognizing that dramatic change cannot happen overnight; this program will, at the outset, demonstrate to chapters their current standing within the Greek Community. This information should be used as baseline data and will provide a starting point from which improvements will be made.Chapters will not be able to maintain status quo. Continued improvement will be expected. At the end of spring semester 2010, One-Star chapters will not be allowed to have any social activities or membership intake until they reach Two-Star status. This allows a One-Star chapter to focus on improvements with academics, leadership, and service without a focus on social activities and recruitment. Chapters at Two-Star status will not be allowed to have any social activities until they reach Three-Star status. A One-Star chapter can only remain in that status for one year before Duquesne University will consider removing recognition from the organization. Two-Star chapters can only remain in that status for two years before Duquesne University will consider removing recognition from the organization.Please note that if any section of the 5-Star packet is not turned in by the designated due date, the chapter will lose all possible points for that section.Scholarship -- 25% of Total Value(250 points possible)It is the position of Duquesne University, the Office of Greek Life, the Interfraternity Council, and the Panhellenic Council that a good chapter places a strong emphasis on scholarship. It is the obligation and expectation of a sorority or fraternity to provide an environment which will be conducive and supportive of the strong academic performance of its members.150 points possible(1). The chapter grade point average exceeds the University's all women's or all men's average.*Each chapter must have an overall grade point average for its full current membership that is at or above the respective male and female campus averages.GPA CATEGORIES:I. Chapter is at or above all men's/all women's average and receives the full150 point award.II. Chapter is within .05 points of the all men's or all women's average will receive 100 points.III. Chapter i s within .10 points of the all men’s or all women’s average will receive 50 points.IV. Chapter is within .20 points of the all men's or all women's average will receive no points. Chapter will receive academic assessment and beplaced on deferred probation.V. Chapter is below .20 points of the all men’s or all women’s average will receive no points. Chapter will receive academic assessment and beplaced on probation.Chapters below the all men's or all women's average will need to continue to improve in order to avoid sanctions. Chapters at or above the all men's or all women's average will need to maintain cumulative GPA's at or above the all men's or all women's average in order to receive the full 150 points in this category. Chapters can move up or down each semester.10 Points (5 per semester)(2) The chapter has an appointed scholarship chairperson who is responsible for monitoring members' academic performance and arranging special programs to meet the chapter's and individual member's needs in this area.*Each chapter must elect a scholarship chair. This individual's name and telephone number must be included in the evaluation report. The scholarship chairperson will be required to submit an outline of his or her scholarship plans from each semester. The scholarship chair will also be required to share any information on scholarship requirements or programming that is provided by the chapter's national organization.20 points (10 per semester)(3) The chapter has developed and implemented a chapter scholarship program that includes a scholarship mission statement, a statement on academic policies, information on programs and resources, and a rewards program. This chapter scholarship program should be outlined and included in the evaluation report. If any academic programming calendars are used by the chapter, include them as well.10 points (5 per semester)(4) Grade point requirement for recruitment and initiation has been established at least a 2.5 cumulative grade point index, or the national fraternity/sorority standards for recruitment and initiation (whichever is higher). Additionally, a GPA requirement for holding office is set at or above this requirement.*Grade point averages for prospective members offered bids will be checked by the Office of Greek Life. Additionally, grades for new members will also be checked and recorded. In order to receive the full point award, chapters will need to monitor the academic performance of their new members and initiates.10 points (5 per semester)(5) The chapter has had all members sign grade release forms in order to determine scholastic status.*A form with each member's signature will be returned with the evaluation report.20 points (10 per semester)(6) At least 80 percent of all members are above a 2.5 GPA each semester or the national fraternity/sorority GPA standards for active membership. Demonstrate programming to assist those members who fall below the chapters minimum GPA standards.*This information will be checked at the conclusion of each academic semester 20 points (10 per semester)(7) The chapter has hosted a program related to academic issues at least once each semester for all chapter members. The description of the program as well as proof of chapter member attendance will be included in the report.。

高尔斯华绥《品质》课件

与个人其他自然主义作品比较
高尔斯华绥的《品质》与他之前的自然主义作品如《自然主义小说集》相比，更注重道德选择和人性光辉。他的自然主义作品强调遗传和环境对人物的影响，而《品质》则更注重人物性格和道德选择对命运的影响。
THANKS
03
艺术特色
叙事手法
叙事视角
小说采用第一人称叙述，通过主人公的视角展现故事情节，增强
了叙述的真实感和可信度。
叙事节奏
作者通过控制叙事节奏，使得故事情节紧凑而富有张力，不断引
发读者的阅读兴趣。
叙事结构
小说采用双线叙事结构，将现实与回忆相互交织，使故事更加丰
富和立体。
语言风格
生动形象
作者运用生动的语言，描绘人物形象和场景，使读者能够更好地理解和感受作品。
作品风格
现实主义
高尔斯华绥的作品以现实主义风格为主，关注社会底层人物的生活和命运。
心理描写
他的作品擅长细腻的心理描写，深入挖掘人物内心世界。
社会批判
高尔斯华绥的作品常常带有强烈的社会批判色彩，揭示社会不公和人性弱点。
02
《品质》内容解析
故事背景
故事发生背景
小说《品质》以英国资本主义经济从自由竞争过渡到垄断阶段为背景，描绘了当时社会上追求利益至上、忽视产品品质的浮躁风气。
其他鞋匠
与格斯拉兄弟形成鲜明对比，他们追求产量和利润，忽视品质，是当时社会风气的代表。
主题思想
对品质的追求
小说通过格斯拉兄弟的故事，强调了对品质的追求和坚守的重要性。
对传统手工艺的捍卫
在工业化和自动化的冲击下，传统手工艺逐渐衰落，小说呼吁对传统手工艺的尊重和保护。
对浮躁风气的批判

EXECUTIVE SUMMARY..........................................................................

DG XIII – E/4 Second Metadata Workshop, 26 June 1998Table of contentsEXECUTIVE SUMMARY (2)1. INTRODUCTION (4)2. SPECIFIC OBJECTIVES OF THE SECOND WORKSHOP (5)3. PARTICIPATION (6)4. STRUCTURE OF THE WORKSHOP (6)5. MORNING SESSION: TECHNICAL ISSUES (6)6. AFTERNOON SESSION: STRATEGIC ISSUES (8)7. CONCLUSIONS (8)8. LIST OF ACRONYMS AND REFERENCES (9)APPENDIX 1. PROGRAMME (13)APPENDIX 2. PRESENTATIONS (14)APPENDIX 3. LIST OF PARTICIPANTS (44)DG XIII – E/4 Second Metadata Workshop, 26 June 1998E XECUTIVE SUMMARYOn 26 June 1998, the second workshop of a series on the subject of metadata organised by the European Commission DGXIII/E4 took place in Luxembourg.32 participants attended the workshop. Many organisations in Europe involved in the implementation of metadata for electronic resources were represented, as were several European Commission services.The workshop contained one session on technical and implementation issues and one session on strategic and standardisation issues reflecting the specific objectives of the workshop.The first specific objective was to give a number of projects the opportunity to present results in the area of metadata from various perspectives. In the morning session, the issues that were covered in the presentations were:metadata creation toolsdefinition of local extensions to Dublin Core for specific application areasthe use of controlled vocabularymultilingual metadataThe presenters of these subjects conducted a panel discussion on these issues and others raised by the audience.The second specific objective was to discuss metadata in a broader context with project participants and experts involved in definition and standardisation of metadata elements. In the afternoon session, presentations covered:metadata activities in contextfuture developments in Dublin CoreIn a plenary discussion, the participants discussed strategic issues concerning the definition and standardisation of metadata element sets.The major conclusions of the workshop can be summarised as follows:the strategic discussions highlighted that establishing widely accepted agreements is essential for the success of metadata;it is necessary that consensus on agreements for metadata is achieved across domains (e.g. libraries, museums, education, business, etc.);agreements and standards need to be maintained over time in a clear and open way with participation of all interested parties (especially user communities) to guarantee stability over time;formal and informal bodies involved in the standardisation of metadata sets (Dublin Core community, CEN, ISO) need to find effective ways of co-operation to ensure maximum acceptance of agreements and to avoid overlapping activities; further metadata workshops organised by the European Commission are considered to be valuable platforms for co-ordination and exchange of experience.DG XIII – E/4 Second Metadata Workshop, 26 June 1998 For further information, including PowerPoint presentations, see the Workshop’s Web site at: http://www2.echo.lu/libraries/en/metadata2.htmlFor more information on the Libraries sector of the Telematics Application Programme, see: http://www2.echo.lu/libraries/en/libraries.htmlDG XIII – E/4 Second Metadata Workshop, 26 June 19981.I NTRODUCTIONThis document is the report of the second Workshop on Metadata, held in Luxembourg on 26 June 1998.DGXIII/E4, the Electronic publishing and libraries unit, is organising a series of workshops on the issue of metadata. Intended participation is from libraries sector projects within the Telematics Applications Programme and from projects in other TAP sectors and other programmes, both EU and national. The primary objectives of the workshops are:To establish a platform for co-ordination between projects concerned with metadata in a broad sense.Under the current Framework Programme for RTD there are a number of projects concerned with metadata as such or with descriptions and descriptors of electronic documents. These projects will come across the same issues and problems and will benefit from concertation, as this will allow them to compare their concepts and approaches with others.To make a wider European community aware of developments in the standards arena and stimulate feedback from the projects to the standards.Developments in metadata in the Internet, specifically in Dublin Core, are moving fast. Some European organisations invest in participating in the Dublin Core workshops but not all have easy access to this activity. By inviting Dublin Core workshop participants to present the developments in the proposed workshops, a wider European audience can be informed on this subject. At the same time, models and experiences from the projects can be fed back into the standards arena.The first workshop which took place on 1 and 2 December 1997, contained a tutorial, project presentations, breakout sessions discussing various aspects of metadata creation and usage.The workshop, although recognising the usefulness of Dublin Core as a starting point in metadata descriptive standards, brought forward a number of concerns regarding the current state and the further development of Dublin Core:•There is currently no formal responsibility for the maintenance of Dublin Core: development takes place in an informal group of invited experts which meets once or twice per year in what is known as the Dublin Core Workshop Series.•The current technical state of Dublin Core is unstable: during the meetings of the Dublin Core group, changes are being made to the format and there is no convergence to a stable version.•The use of the current Dublin Core metadata format is not supported by the existence of guidelines: some of the philosophy and terminology of Dublin Core isDG XIII – E/4 Second Metadata Workshop, 26 June 1998 not obvious to the uninitiated user which could lead to different interpretations adversely affecting interoperability.It was also identified that the current take-up of Dublin Core is slow and that there is a lack of critical mass. This seems to be a classical chicken-and-egg situation: authors and publishers do not invest in providing Dublin Core metadata if the Internet indexing services (the ‘harvesters’) do not utilise it, and harvesters do not collect Dublin Core and use it for selective indexing if there is not enough data available. If this situation cannot be changed, Dublin Core might not turn into reality.The workshop identified a number of actions that could be taken to promote and encourage the use of Dublin Core, including the following:1.There needs to be clarity about version control and maintenance of Dublin Core.The Dublin Core group, addressed through the mailing list META2, will be asked to give a clear statement about this.2.Further pilot projects should be started to further develop experience, test out theissues and help realise a critical mass of Dublin Core metadata. The European Commission and national bodies like National Libraries might have a role to play by encouraging the provision of Dublin Core metadata in documents, e.g. in project deliverables and electronic documents in the national deposit.3.The interest and requirements existing in Europe warrant the establishment of aEuropean group of implementers discussing the practical issues of implementing metadata in general and Dublin Core in particular. The Luxembourg workshops, such as this December 1997 one and a second one scheduled for mid-1998, could develop into a regular series.4.The liaison with other groups concerned with metadata, such as the CEN/ISSSworking group on Metadata for Multimedia Information (MMI), should be established to ensure applicability and interoperability of metadata as widely as possible and cover the needs of a wide range of communities.The report of the first workshop is available on the Web at http://www2.echo.lu/libraries/en/metadata.html.2.S PECIFIC OBJECTIVES OF THE SECOND WORKSHOPThe specific objectives of this second workshop, held in Luxembourg on 26 June 1998, were as follows.The first specific objective of the second workshop was to give a number of projects the opportunity to present results in the area of metadata from various perspectives. In the morning session, the issues that were covered in the presentations were:•metadata creation tools•definition of local extensions to Dublin Core for specific application areasDG XIII – E/4 Second Metadata Workshop, 26 June 1998•the use of controlled vocabulary•multilingual metadataThe presenters of these subjects conducted a panel discussion on these issues and others raised by the audience.The second specific objective was to discuss metadata in a broader context with project participants and experts involved in definition and standardisation of metadata elements. In the afternoon session, presentations covered:•metadata activities in context•future developments in Dublin CoreIn a plenary discussion, the participants discussed strategic issues concerning the definition and standardisation of metadata element sets.The programme of the workshop is attached in Appendix 1. Printouts of the presentation, with short biographical notes of the presenters are attached in appendix 2.3.P ARTICIPATION32 persons representing projects from the Telematics programme, national projects and various Commission services attended the workshop.The list of participants is attached as appendix 3.4.S TRUCTURE OF THE WORKSHOPThis second workshop was organised on a single day and contained two sessions: one session on technical and implementation issues and one session on strategic and standardisation issues reflecting the specific objectives of the workshop.5.M ORNING SESSION: TECHNICAL ISSUESIn the first presentation, Anna B RÜMMER of Lund University in Sweden demonstrated metadata creation software constructed for the Nordic Metadata Project. This creation software on the Web offers an easy way to attach descriptive metadata to resources and has helped to build the SweMeta Dublin Core Database for Sweden, which contains 110.000 records. The system also allows users to assign a unique URN to their resource. Currently there is no statistical information on the use of the various elements, which could provide interesting information. There is no validation of the terms entered. This could be considered in the future.Erik D UVAL of Leuven University in Belgium presented the Ariadne project aiming at sharing and re-use of pedagogical resources to make the best use of scarce high-quality material for educational purposes. The project provides authoring tools that produce base metadata, which helps in creating a corpus of consistent descriptions. The project constitutes a closed environment for the participants, allowing a strongDG XIII – E/4 Second Metadata Workshop, 26 June 1998 exercise of editorial control and therefore of quality. Furthermore, users have the possibility to add annotations to the descriptions. A “Replicator Scheme” controls the distribution and access to the resources available in the Central Pool and the Local Pools in various places around Europe. The project has not reached the stage where a critical mass of material is available and is looking for further participants. The Ariadne project is co-operating with the IMS (Instructional Management Systems) project to co-ordinate the metadata definitions and agree a common metadata set. This set is not technically speaking Dublin Core as it has a richer structure and contains elements specific to educational use of the resources, but the mapping of Dublin Core into the Ariadne metadata set is considered to be possible. Also the project participates in the work in the IEEE Learning Technology Standards Committee which develops technical Standards, Recommended Practices, and Guides for software components, tools, technologies and design methods that facilitate the development, deployment, maintenance and interoperation of computer implementations of education and training components and systems.Paul M ILLER of the Archaeology Data Service in the UK introduced the advantages of using controlled vocabularies and thesauri. For users, these tools would help gaining more effective access to resources and reduce the number of false hits. Creators would be able to make more consistent descriptions and achieve a better integration of new and existing resources. It was noted that a major factor for the use of controlled vocabulary is the ease with which it can be used in both the process of creation of metadata and in the process of searching.Matthew S TIFF of the Museum Documentation Association in the UK spoke about multilingual aspects of information retrieval. He discussed the creation of parallel metadata in multiple languages versus the use of translation tools and multilingual thesauri. He identified the need for new tools but also noted these tools will be expensive and will take a lot of time to develop. Various options can be explored to create multilingual thesauri, including linking existing monolingual ones and translating one thesaurus in multiple languages. He touched upon the fundamental issue of incomplete equivalence of terms in different languages. Project Term-IT is investigating mechanisms to facilitate the production and dissemination of multilingual thesauri in the cultural sector through establishing dialogue with users and analysis of the economics of thesaurus production.As a conclusion of the technical session it was identified that:quality is a crucial issue both in the creation of metadata and in its maintenance there should be a clear focus on the user when designing tools to help create and use metadata; user communities should be actively involved to make sure their requirements are taken into accountspecial attention must be given to the change in concepts and terminologies over time.DG XIII – E/4 Second Metadata Workshop, 26 June 19986.A FTERNOON SESSION: STRATEGIC ISSUESThe first presentation in the afternoon session was delivered by Ian C AMPBELL-G RANT of ICL, chairman of the CEN/ISSS Workshop on Metadata for Multimedia Information. He introduced the work of this group as part of a new approach to standardisation especially intended to achieve rapid agreements on standards and a wide acceptance n the market. The specific objectives of the group include to gather information on metadata activities, to identify gaps and overlaps in current work and to disseminate this information to European industry, projects and programmes. The group is currently working to establish a framework that will help to find existing activities in the area of metadata definition.In the final presentation, Stuart W EIBEL of OCLC in the US presented the current state and the future prospects for the Dublin Core metadata initiative. He outlined the objectives of the initiative, noting that it is a simple set for descriptive elements that are relevant for resource discovery. It could be used as a cross-domain “switching”language, working together with other sets in the framework provided by RDF. He presented the current thinking on the issue of more formally standardising Dublin Core, working through any body that would be appropriate for that purpose (IETF, ISO, NISO, CEN/ISSS).In the discussion that took place after the presentations, several aspects were identified:the involvement of user communities and business areas is crucial to make sure their requirements are being taken into accountagain the issue of critical mass was raised: Dublin Core and other structured metadata forms an ‘island in the sea of marked data’. There needs to be more metadata before it can produce benefits to the users.the CEN/ISSS workshop could form an appropriate platform for rapid standardisation of Dublin Core in the form of a CEN Workshop Agreement; this needs to be further explored.the issue of maintenance of metadata standards is very important. The mechanism and structure should allow open and international participation to ensure the widest possible and agreement7.C ONCLUSIONSThe major conclusions of the workshop can be summarised as follows:the strategic discussions highlighted that establishing widely accepted agreements is essential for the success of metadata;it is necessary that consensus on agreements for metadata is achieved across domains (e.g. libraries, museums, education, business, etc.);agreements and standards need to be maintained over time in a clear and open way with participation of all interested parties (especially user communities) to guarantee stability over time;DG XIII – E/4 Second Metadata Workshop, 26 June 1998formal and informal bodies involved in the standardisation of metadata sets (Dublin Core community, CEN, ISO) need to find effective ways of co-operation to ensure maximum acceptance of agreements and to avoid overlapping activities; further metadata workshops organised by the European Commission are considered to be valuable platforms for co-ordination and exchange of experience.8.L IST OF ACRONYMS AND REFERENCESACM the Association for Computing Machinery, an internationalscientific and educational organization dedicated to advancingthe arts, sciences, and applications of information technology.ADS Archaeology Data Service./ahds/AHDS Arts and Humanities Data Service./ALA American Library Association./ALCTS /ccda/Ariadne RTD project under the "Telematics for Education andTraining" sector of the 4th Framework Programme of theEuropean Union. The project focuses on the development oftools and methodologies for producing, managing and reusingcomputer-based pedagogical elements and telematicssupported training curricula.http://ariadne.unil.ch/CEN European Committee for Standardisation.http://www.cenorm.be/CEN/ISSS European Committee for Standardisation - InformationSociety Standardisation System.http://www.cenorm.be/isss/default.htmCIDOC The International Committee for Documentation of theInternational Council of Museums (ICOM), the internationalfocus for the documentation interests of museums and similarorganisations./CIMI Consortium for the Computer Interchange of MuseumInformation./CPA Commission on Preservation and Access./programs/cpa/cpa.htmlDC Acronym for Dublin CoreDesire Telematics for Research project addressing the needs ofresearch users in the context of a European informationnetwork based on the World Wide Web (WWW).http://www.surfnet.nl/surfnet/projects/desire/DG XIII Directorate General XIII of the European Commission.http://europa.eu.int/en/comm/dg13/13home.htm. See also:http://www2.echo.lu/home.htmlDublin Core Dublin Core is a 15-element metadata element set intended tofacilitate discovery of electronic resources./metadata/dublin_core/EC European Commission.http://europa.eu.int/ERCIM The European Research Consortium for Informatics andMathematics - aims to foster collaborative work within theEuropean research community and to increase co-operationwith European industry.EULER Telematics for Libraries project aiming to provide user-oriented, integrated network based access to mathematicalpublications.http://www.emis.de/projects/EULER/ICL /ICOM The International Council of Museums, a Non-GovernmentalOrganisation (NGO) maintaining formal relations with UNESCO,devoted to the promotion and development of museums and themuseum profession at an international level./IEEE The Institute Of Electrical And Electronics Engineers, Inc., atechnical professional society with the objective to advance thetheory and practice of electrical, electronics and computerengineering and computer science.IETF The Internet Engineering Task Force, a large openinternational community of network designers, operators,vendors, and researchers concerned with the evolution of theInternet architecture and the smooth operation of theInternet.IMS Instructional Management Systems Project, an investmentmembership of academic, commercial and governmentorganisations developing a set of specifications and prototypesoftware for facilitating the growth and viability of distributedlearning on the Internet./ISO International Organisation for Standardisation.http://www.iso.ch/MDA Museum Documentation Association, body in the UK formuseum information management, supporting museums in allaspects of heritage information management including thecrucial area of Information and Communications Technology(ICT)./MIT Massachusetts Institute of Technology./MMI CEN/ISSS Workshop on Metadata for MultimediaInformation.http://www.cenorm.be/isss/Workshop/MMI/Default.htm NGDF National Geospatial Data Framework (UK)./NISO U.S. National Information Standards Organization:Nordic Metadata Scandinavian co-operation project creating basic elements of a metadata production and utilisation system:http://renki.helsinki.fi/meta/NSF National Science Foundation (US), an independent U.S.government agency responsible for promoting science andengineering through programs that invest in research andeducation projects in science and engineering./OCLC Online Computer Library Center, Inc., a non-profit, membership, library computer service and researchorganisation in Dublin, Ohio, USARDF Resource Description Framework, a specification currentlyunder development, designed to provide an infrastructure tosupport metadata across many web-based activities:/RDF/RLG Research Libraries Group.RTD Research & Technological DevelopmentSweMeta Dublin Core Database for Sweden.TAP The Telematics Applications Programme, one of theEuropean Commission's research programmes, aimed atstimulating RTD on applications of information and/orcommunications technologies in areas of general interest:http://www2.echo.lu/telematics/telehome2.htmlTEISS Telematics - European Industry Standards SupportTelematics for Libraries The Libraries sector of the Telematics Applications Programme:http://www2.echo.lu/libraries/en/libraries.htmlTerm-IT a preparatory-phase project under the Language Engineeringsector of the Telematics Applications Programme, aimed atleading to the development of methods and systems toimprove the production, dissemination and exploitation ofmultilingual terminology resources/term-it/URN Universal Resource Name:/html.charters/urn-charter.htmlA PPENDIX 1.P ROGRAMMEMETADATA WORKSHOP 26 JUNE 1998EUROFORUM Building352*5$00(09:00-09:20Welcome, registrationPatricia Manson, European Commission DG XIII/E-409:20-09:30IntroductionMakx D EKKERS, The Libraries Support Team0RUQLQJ VHVVLRQ 7HFKQLFDO LVVXHV09:30-10:00Metadata creation toolsAnna B RÜMMER, Univ. of Lund10:00-10:30Extension of Dublin Core for Educational materialErik D UVAL, Univ. of Leuven10:30-11:00Coffee break11:00-11:30Controlled vocabularyPaul M ILLER, Archaeology Data Service11:30-12:00Multilingual issuesMatthew S TIFF, Museum Documentation Association12:00-12:30Panel discussion12:30-13:30Lunch break$IWHUQRRQ VHVVLRQ 6WUDWHJLF LVVXHV13:30-14:00Metadata activities in contextIan C AMPBELL-G RANT, ICL (chair CEN/ISSS open Workshop on Metadatafor Multimedia Information)14:00-14:30Future developments in Dublin CoreStuart W EIBEL, OCLC14:30-15:00Tea break15:00-15:45Discussion15:45-16:00Wrap-up and closingAriane I LJON, Head of Unit, European Commission DG XIII/E-4A PPENDIX 2.P RESENTATIONSMetadata creation toolsAnna B RÜMMER, Univ. of LundBiographical note:Anna Brümmer is an electronic information services librarian at Lund University Library development department NetLab since the first of February 1996. She began after having finished her studies in library and information science in January 1996. Between 1996-1998 she has, among other things, been involved in the EU-project DESIRE, the Development of a European Service for Information on Research and Education. She is also involved in project EULER, European Libraries and Electronic Resources in Mathematical Sciences, integrating bibliographic databases, library online public access catalogues, electronic journals from academic publishers, online archives of pre-prints and grey literature, and indexes of mathematical Internet resources. For the time being she is the pro tem. head of NetLab.Abstract:Metadata tags are, in an end user perspective, complicated to produce. The talk presented one solution aiming to facilitate the metadata creation process (for end users): a metadata creation tool. The presentation described the issues involved in, and related to, the Dublin Core metadata creation and provided explanations on construction of DC Metadata records. The starting point was the Nordic Metadata project, which has developed basic elements of a metadata production and utilisation system, based on the Dublin Core Metadata Element Set. The result is the Nordic Metadata DC production template/creator, which was demonstrated at the workshop.The presentation included a short introduction to the web resource identifier URN (Uniform Resource Names) and an URN generator.The presentation is available on the Web at:http://www.lub.lu.se/EULER/presentations/creator.html.(one page print-out of Web page)Extension of Dublin Core for EducationalmaterialErik D UVAL, Univ. of LeuvenBiographical note:Erik Duval is a post-doctoral fellow of the National Fund for Scientific Research - Flanders and a part-time professor at the Katholieke Universiteit Leuven, Belgium. His main research areas are distributed hypermedia systems, data modelling, the application of information and communication technology in education, metadata and computer science education. He co-ordinates the development of the Knowledge Pool System for the ARIADNE project and is a member of the IEEE Computer Society, the ACM and the program committee of the WebNet Conference Series.Abstract:This presentation covered the current status of the author’s work on educational metadata. Since about two years, the ARIADNE project has developed both a structure and an infrastructure for educational metadata <http://ariadne.unil.ch>. The structure extends Dublin Core to a considerable extent and includes circa 70 data elements, grouped in 9 categories and defined over abstract data types. The infrastructure includes a tool for describing pedagogical documents and a distributed database of these documents and their descriptions, called the Knowledge Pool System. The ARIADNE results have been input in standardisation work in the Learning Object Metadata Working Group of the IEEE Learning Technology Standards Committee </p1484>.(6 pages printout of PowerPoint presentation, 6 slides to a page)(6 pages printout of PowerPoint presentation, 6 slides to a page)(6 pages printout of PowerPoint presentation, 6 slides to a page)(6 pages printout of PowerPoint presentation, 6 slides to a page)(6 pages printout of PowerPoint presentation, 6 slides to a page)(6 pages printout of PowerPoint presentation, 6 slides to a page)Controlled vocabularyPaul M ILLER, ADSBiographical note:Dr. Paul Miller is Collections Manager for the Archaeology Data Service (ADS)</>, one of five service providers comprising the Arts & Humanities Data Service (AHDS) </> in the United Kingdom.The ADS seeks to both preserve and encourage the reuse of digital archaeological data, whether by physically taking and mounting data or by working with existing organisations and technologies to facilitate distributed access mechanisms.Paul is responsible for the development of this distributed catalogue, and is closely involved with a number of evolving metadata initiatives around the world. These include the Dublin Core </metadata/dublin_core>, the UK's National Geospatial Data Framework (NGDF) </>, and the work of the Consortium for the Computer Interchange of Museum Information (CIMI) </>.Abstract:This presentation went into the problems of terminology and vocabulary, which become increasingly apparent as opportunities for cross-searching between different data sources grow. Efforts to develop controlled lists of terms have been relatively isolated in individual disciplines or geographic areas.With the current explosion in projects to provide remote access to these resources, and initiatives to link diverse resources together for the first time, new problems have arisen, namely;•divorcing of resources from the local expertise developed to support and maintain them •integrating diverse terminologies•contextualising the terminologies•providing access to the terminologiesIn conclusion, controlled terminology remains an important weapon in the information scientist's arsenal, but the new distributed world in which these terminologies are increasingly being used perhaps requires a new approach to some old problems, an approach which was explored in this paper.。

PHOENICS中文教程

目录目录 (1)1简介 (5)1.1FLAIR是什么? (5)1.2FLAIR 可以做些什么？ (8)1.3FLAIR 组成部分以及PHOENICS的关系 (9)1.3.1FLAIR模块 (9)1.3.2FLAIR与PHOENICS的关系 (9)1.4FLAIR 与众不同的功能 (9)1.4.1用户接口功能(In-Form) (9)1.4.2自动收敛控制 (10)1.4.3PARSOL技术 (10)1.4.4嵌套网格 (11)1.4.5LVEL 湍流模型 (12)1.4.6IMMERSOL 辐射模型 (12)2启动FLAIR程序 (14)2.1FLAIR的操作方式 (14)2.1.1Satellite ....................................................................................... 错误！未定义书签。

2.1.2Commander................................................................................ 错误！未定义书签。

2.1.3VR-Environment......................................................................... 错误！未定义书签。

2.2FLAIR 在线帮助和用户手册 (14)2.2.1Problem description (15)2.2.2建立模型 (15)2.2.3启动求解器 (24)2.2.4使用VR-Viewer 查看结果 (25)2.2.5从VR中打印图片 (28)2.2.6总结 (29)3暖通设备组件和暖通模型 (30)3.1可以使用的那些模型文件和介绍....................................................... 错误！未定义书签。

Fourth+Grade+English+Volume+1+Unit+8

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THE FIRST LESSON OF THE SCHOOL YEAR
本单元的重点词汇包括动物名称（如狮子、猴子、大象等）、颜色名称（如红色、黄色、蓝色等）、以及一些描述动物特征和行为的形容词（如大的、小的、快乐的、悲伤的等）。学生需要能够正确拼写这些词汇，理解其含义，并在上下文中正确使用。
本单元的语法难点主要涉及形容词和副词的比较级形式，以及一些常见的动词短语。
通过例句和练习，理解句子结构，提高句子表达能力。
理解文章内容
分析本单元的课文，理解文章的主题、情节和人物关系，学习如何提取文章中的重要信息。
通过阅读理解和问题回答练习，提高阅读理解能力。
01
Analysis of key and difficult points in the unit
掌握本单元的重点词汇是理解课文和完成相关练习的基础。
录
01
Unit Theme Introduction
Theme: "My Community"
The unit explores the concept of community, focusing on the people, places, and activities that make up a community.
Fourth Grade English Volume 1 Unit 8
目
CONTENTS
Unit Theme IntroductionOverview of Unit ContentAnalysis of key and difficult points in the unitUnit learning strategies and techniquesUnit learning evaluation and feedback

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●群文阅读全球掀起“汉语热”Reading Check1~4CDBD汉字之美Reading Check1~4CBAC我的英语学习之路Reading Check1~4BCAD走进塞缪尔·约翰逊的词典世界Reading Check1~4DCBC最难学习的语言Reading Check1~4DCABLanguage StudyⅡ.The harder you study,the more you ll get.拯救濒危语言Reading Check1~4DBBA主题应用·语库构建Dear Paul,Hearing that you run into difficulties with your Chinese listening,I m writing to express my concern and offer you some ad⁃vice on how to learn it well.Your problem is so common among foreign learners that you needn t worry too much.As the saying goes,“Practice makes perfect!”So it s a good idea to practice Chi⁃nese daily.Besides,listening to Chinese radio programs is a good choice,which can not only entertain you,but also improve your listening skills.Additionally,you can communicate with your Chinese teacher who can tell you how to improve your Chi⁃nese listening ability effectively.I hope my advice can be helpful! Wish you all the best.Yours,Li Hua ●时文精粹非遗人物志：薛生金Reading Check1~4BCBD小蓝企鹅，萌宠上线Reading Check1~4DCBD“阳光市长”Reading Check1~4CABC参考答案童年的沙堡Reading Check1~4CDBA拯救阿托亚克河Reading Check1~4CBAD中国传统纹样保护者Reading Check1~4BCDB●纯享悦读“希望”摄影展Reading CheckThey feel excited.六岁萌娃，高尔夫冠军Reading CheckAny answer can be possible as long as it makes sense.非洲之巅，“无线”风光Reading CheckSafety is the main reason for setting up the Internet service on the mountain.餐厅菜单上的碳足迹Reading CheckThe Canteen sent its recipes and the source of the ingredients to a specialized company called MyEmissions.南极探险日常Reading CheckAny answer can be possible as long as it makes sense.《无穷之路》第二季“生态”回归Reading CheckShe acts as a guide for audiences in the documentary.无人机助力消防“降火”Reading CheckAny answer can be possible as long as it makes sense.●巧读妙写猩猩的招呼语一、阅读自测1~4BDCA四、语言运用（一）例句仿写1.not only enjoyed;but also made2.that s why I think（二）写作实践Dear Mr Smith,I feel greatly honored to write and ex⁃tend our thanks to you on behalf of my fel⁃low students.How I wish that you could continue to be with us.More than a year has passed since you came to our school for the exchange program.We have been greatly inspired by your good behavior and sense of duty.In the past year,not only did you teach us knowledge,but also you taught us how tobehave.With your encouragement,we be⁃gan to communicate with each other in English whenever possible.Besides,our understanding of English and its culture has been greatly enhanced.Thank you again.Wish you a pleasant journey home and all the best for the fu⁃ture.Yours,Li Hua学习汉语的诀窍一、阅读自测1~3DBD四、语言运用（一）例句仿写1.It took him several weeks to make the gift2.whatever he decides to do3.Not only did we donate money to them（二）写作实践Dear Jack,I admire your passion for the Chinese language and I m more than happy to give you some help.Here is a popular four⁃word Chinese idiom which I think you might be inter⁃ested in.It is called Shou Zhu Dai Tu.It is used to describe someone who is lazy and sits around and waits for something good to happen.The idiom originated from the story of a farmer who saw a rabbit bump into a tree stump and die.This gave him the idea of waiting near the tree stump for more rabbits to kill themselves that way. The farmer waited for a long time,but such a coincidence did not occur again. The lesson behind this idiom is—if we really long for something,we have to strive for it.Yours sincerely,Li Hua ●写作园地语言学习博客写作写作指导三、完成句子1.I ll offer/give you some advice2.In my opinion/From my point of view3.You d better4.in context5.enlarge your vocabulary6.My problem is that四、句式升级1.I will offer you some advice whichwill help you to remember words.2.From my point of view,you must learn to read English words first instead of only being able to spell them.3.You had better remember more phrases and make up more sentences be⁃cause words will be learned better in con⁃text.4.Reading more English articles is also of great importance for you to enlarge your vocabulary.五、连句成篇I will offer you some advice which will help you to remember English words. From my point of view,you must learn to read English words first instead of only be⁃ing able to spell them.In addition,you had better remember more phrases and make up more sentences because words will be learned better in context.Furthermore,read⁃ing more English articles is also of great importance for you to enlarge your vocabu⁃lary.Do remember to take notes when you meet with some unknown words.My prob⁃lem is that I can t write well.Who can give me some good advice?小试牛刀I ll give some suggestions on improv⁃ing your English reading speed.One is to divide the text into some sections and read the text in each section.Another sugges⁃tion is to skim the main idea first.Take reading a novel as an example.Taking ad⁃vantage of the title,the table of contents, subtitles,captions under pictures,and the first paragraph,we can easily piece them together and grasp the gist of the story. With these reading techniques,you will ab⁃sorb more information while reading and read faster.I sometimes have trouble with English speaking.Any advice?决胜“人堆城堡”一、语篇研读（一）基本要素1.Jordi s2.because3.encouraging4.making5.won6.believe（二）主题探究The text is about the author s experi⁃ence of being a castle builder.The author wants to tell us that with faith in each other and with focus on the task,we can succeed.二、语言学习（一）词块1.坐起来2.犹豫不决……3.挤满；装满；充满4.和……一起站着5.如果……怎么办6.肯定7.相信；信任8.抬起；举起9.尽力10.组成；构成；编造（三）即学即用1.Never shall I forget the days when you were with us.2.Just then I noticed,for the first time,that our master was wearing his fine green coat and his black silk cap.3.As I waited at the stop,I heard a big noise.4.Rights are won only by those who make their voices heard.四、续写布局Paragraph1:I place my foot into Mom s waist belt and try to stand,but it slips off.Fortu⁃nately,Mom grasps me by the wrist before I lose my balance and tumble backwards. My heart leaps into my throat.Panic is rip⁃pling through me so fiercely that my whole body shivers.“Tranquil.Easy,”Mom whis⁃pers soothingly.I take a deep breath to calm myself.I cannot let my team down. Meanwhile,Tomeu s words echo in my mind,“Have focus.Have faith.”I again place my foot into Mom s belt.This time,my toes grip firmly.Slowly but steadily,I step up and onto her shoulders. Opposite me,Tomeu has also made it to the top.Paragraph2:Tomeu and I grasp each other s arms, and our tower is complete.I breathe a sigh of relief.It is not until this moment that I truly feel the charm of castle building.I am no longer frightened.Beneath me,the base feels strong,and my heart beats steady in my chest.Far below,I can hear the crowd s cheering.I smile across at Tomeu.We win this competition,and I know we have done our best.Our team has worked together.With faith in each other and with focus on the task,we have built our castle.Today,I am a casteller!●自测园地世界各地的语言第一部分单句语法填空1.based2.reference3.varieties4.global5.beggar6.equality7.description8.appreciation9.to 10.to/towards11.majority12.leaving 13.has14.struggled15.related第二部分完成句子1.ups and downs2.date back to3.Along with4.Neither you nor I5.no matter when6.of no interest to7.It was a time when8.the more excited9.The reason why10.in which第三部分阅读第一节A本文是一篇应用文。

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