A seasonal study of polycyclic aromatic hydrocarbons in PM2.5and PM2.5–10in

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210978218_响应面优化金丝小枣碱提多糖工艺及其抗氧化活性研究

王娜，刘玉叶，刘美玲，等. 响应面优化金丝小枣碱提多糖工艺及其抗氧化活性研究[J]. 食品工业科技，2023，44（7）：163−169. doi:10.13386/j.issn1002-0306.2022060026WANG Na, LIU Yuye, LIU Meiling, et al. Optimization of Alkali Extraction Process of ‘Jinsixiaozao’ Polysaccharide by Response Surface Methodology and Its Antioxidant Activity[J]. Science and Technology of Food Industry, 2023, 44(7): 163−169. (in Chinese with English abstract). doi: 10.13386/j.issn1002-0306.2022060026· 工艺技术 ·响应面优化金丝小枣碱提多糖工艺及其抗氧化活性研究王　娜1，刘玉叶1，刘美玲1，刘孟军1,2，赵智慧1,2, *（1.河北农业大学园艺学院，河北保定 071001；2.河北农业大学枣研究中心，河北保定 071001）摘　要：以金丝小枣为原料，通过单因素考察提取温度、时间、料液比和NaOH 浓度对多糖得率的影响，在此基础上进行Box-Behnken 试验来优化碱提多糖的提取工艺，并对其进行总糖含量、扫描电镜、红外光谱及抗氧化活性测定。

结果表明，碱提多糖最佳工艺为：料液比1:35（g/mL ），提取温度80 ℃，提取时间120 min ，NaOH 浓度为0.2 mol/L ，在此条件下多糖的得率为11.44%，总糖含量为69.39%。

扫描电镜表明其具有不规则块状结构，内部紧实；红外光谱表明枣碱提多糖具有C=O 和C-H 等酸性多糖的特征吸收峰。

特性结构表面

The role of natural and synthetic zeolites as feed additives on the prevention and/or the treatment of certain farmanimal diseases:A reviewD.Papaioannou,P.D.Katsoulos,N.Panousis *,H.KaratziasClinic of Productive Animal Medicine,School of Veterinary Medicine,Aristotle University of Thessaloniki,54124Thessaloniki,GreeceReceived 4April 2005;received in revised form 12May 2005;accepted 12May 2005Available online 28June 2005AbstractThe present review comments on the role of the use of zeolites as feed additives on the prevention and/or the treatment of certain farm animal diseases.Both natural and synthetic zeolites have been used in animal nutrition mainly to improve performance traits and,based on their fundamental physicochemical properties,they were also tested and found to be eﬃcacious in the prevention of ammonia and heavy metal toxicities,poisonings as well as radioactive elements uptake and metabolic skeletal defects.During the last decade,their utilization as mycotoxin-binding adsorbents has been a topic of considerable interest and many published research data indicate their potential eﬃcacy against diﬀerent types of mycotoxins either as a primary material or after speciﬁc modiﬁcations related to their surface properties.Ingested zeolites are involved in many biochemical processes through ion exchange,adsorption and catalysis.Recent ﬁndings support their role in the prevention of certain metabolic diseases in dairy cows,as well as their shifting eﬀect on nitrogen excretion from urine to faeces in monogastric animals,which results in lower aerial ammonia concentration in the conﬁnement facilities.Moreover,new evidence provide insights into potential mechanisms involved in zeolites supporting eﬀect on animals suﬀered from gastrointestinal disturbances,including intestinal parasite infections.All the proposed mechanisms of zeolites Õeﬀects are summarized in the present review and possible focus topics for further research in selected areas are suggested.Ó2005Elsevier Inc.All rights reserved.Keywords:Zeolites;Animal health;Prevention;Treatment1.IntroductionZeolites are crystalline,hydrated aluminosilicates of alkali and alkaline earth cations,consisting of three-dimensional frameworks of SiO 4À4and AlO 5À4tetrahedra linked through the shared oxygen atoms.Both natural and synthetic zeolites are porous materials,character-ized by the ability to lose and gain water reversibly,to adsorb molecules of appropriate cross-sectional diame-ter (adsorption property,or acting as molecular sieves)and to exchange their constituent cations without majorchange of their structure (ion-exchange property)[1,2].The exploitation of these properties underlies the use of zeolites in a wide range of industrial and agricultural applications and particularly in animal nutrition since mid-1960s [3].Many researchers have proved that the dietary inclu-sion of zeolites improves average daily gain and/or feed conversion in pigs [1,4–13],calves [1,7],sheep [7,14–16],and broilers [17–19].Zeolites also enhance the reproduc-tive performance of sows [1,20,21],increase the milk yield of dairy cows [22,23]and the egg production of laying hens [24,25]and have beneﬁcial eﬀects on egg weight and the interior egg characteristics [24–26].How-ever,the extent of performance enhancement eﬀects is related to the type of the used zeolite,its purity and1387-1811/$-see front matter Ó2005Elsevier Inc.All rights reserved.doi:10.1016/j.micromeso.2005.05.030*Corresponding author.Tel.:+302310994501;fax:+302310994550.E-mail address:panousis@vet.auth.gr (N.Panousis)./locate/micromesoMicroporous and Mesoporous Materials 84(2005)161–170physicochemical properties,as well as to the supplemen-tation level used in the diets.Besides,the particle size of the zeolitic material,crystallite size and the degree of aggregation,as well as the porosity of individual parti-cles determine the access of ingestaﬂuids to the zeolitic surface during passage across gastrointestinal tract and strongly aﬀect its ion exchange,adsorption and catalytic properties.Table1summarizes the possible mechanisms by which zeolites may exert their performance promot-ing properties in farm animals.Apart from the positive eﬀects on animalsÕperfor-mance,dietary supplementation of zeolites appears to represent an eﬃcacious,complementary,supportive strategy in the prevention of certain diseases and the improvement of animalsÕhealth status.The aim of the present review article is to address the data concerning the inﬂuence of the in-feed inclusion of natural and syn-thetic zeolites on certain diseases of farm animals,to summarize the proposed mechanisms of zeolitesÕeﬀects and to suggest possible focus topics for further research in selected areas.2.Ameliorative eﬀect on the consequences of mycotoxicosesIn the recent years,high incidence rates of contami-nation of cereal grains and animal feed with mycotoxins are reported worldwide[38].One of the latest ap-proaches to this global concern has been the use of nutritionally inert adsorbents in the diet that sequester mycotoxins,thus reducing intestinal absorption and, additionally,avoiding toxic eﬀects for livestock and the carry-over of toxin compounds to animal products. For this purpose,phyllosilicates such as hydrated sodium calcium aluminosilicates(HSCAS)and benton-ite––which consist of layered crystalline structures and possess similar physicochemical properties with zeo-lites––have beenﬁrst used successfully in poultry,pig, sheep,cattle and laboratory animals[33,34,39–47].Apart from phyllosilicates,the use of zeolites has shown,lately,very promising results as well.In general, adsorption process on binders is strongly related to charge distribution,pore dimensions and accessible sur-face area of the adsorbent,as well as to polarity,solubil-ity and molecular dimensions of the certain mycotoxin which is to be adsorbed[46].Molecular sizes of aﬂatox-ins range from5.18A˚(B1and B2)to6.50A˚(G1and G2) and only zeolites with entry channels wide enough to permit the diﬀusion of aﬂatoxin molecules to the intra-crystalline structure are capable of demonstrating a clear sequestering eﬀect.Clinoptilolite,a natural zeolite,has high adsorption indexes in vitro,more than80%,for aﬂatoxins B1[48,49]and G2[48]and the adsorption pro-cess begins with a fast reaction whereby most of the toxin is adsorbed within theﬁrst few minutes[48].On the contrary,Lemke et al.[50]conducted a variety of in vitro adsorption studies and reported a limited degree of clinoptilolite ability to bind aﬂatoxin B1eﬀectively. According to them,adsorbent materials should be checked through a multi-tiered system of in vitro tests in order potential interactive factors,such as intestinal physicochemical variables and feed components,to be precluded.Indeed,a previous in vitro study had demon-strated average aﬂatoxin retention in natural zeolites of 60%,but also a nitrogen compound-related adsorbent eﬀectiveness,when liquid media quality parameters had been taken into account[51].The in vivo eﬃcacy of zeolites to ameliorate the consequences of aﬂatoxico-sis,mainly in poultry,has also been veriﬁed in many cases(Table2).In the case of phyllosilicates,the results of in vitro mycotoxin–clay interaction tests suggest the existence of areas of heterogenous adsorption aﬃnities onto sur-face,the presence of diﬀerent adsorption mechanisms or both[57].Nevertheless,the formation of strong bonds by chemisorption and the interaction of b-car-bonyl group of aﬂatoxin B1with the uncoordinated edge site aluminum ions in these adsorbents have been suggested as the binding mechanism which interprets their well-established high aﬃnity for aﬂatoxin B1 [39,58,59].Although the exact binding mechanisms of zeolites on aﬂatoxins have not been determined the pos-sibility to act through similar with phyllosilicates mech-anism cannot be precluded and should be investigated.As far as other mycotoxins are concerned,mineral adsorbents exert a lower eﬃcacy against mycotoxins containing less polar functional groups,which are required for eﬃcient chemisorption on hydrophilic negatively charged mineral surfaces to occur.This limi-tation can be overcome by the use of chemically modi-ﬁed clays.Modiﬁcations consist of alterations ofTable1Proposed mechanisms involved in animalsÕperformance promoting properties of the dietary use of zeolitesMechanismsAmmonia binding eﬀect Elimination of toxic eﬀects of NHþ4produced by intestinal microbial activity[8,10]Fecal elimination of p-cresol Reduction of the absorption of toxic products of intestinal microbial degradation,such as p-cresol[27] Retarding eﬀect on digesta transit Slower passage rate of digesta through the intestines and more eﬃcient use of nutrients[1,25,28] Enhanced pancreatic enzymes activity Favorable eﬀect on feed components hydrolysis over a wider range of pH,improved energy and protein retention[29,30]Aﬂatoxin sequestering eﬀect Elimination of mycotoxin growth inhibitory eﬀects[31–37]162 D.Papaioannou et al./Microporous and Mesoporous Materials84(2005)161–170surface properties resulting in an increased hydropho-bicity,by exchange of structural charge-balance cations with high molecular weight quaternary amines.In vitro results have veriﬁed the binding eﬃcacy of modiﬁed montmorilonite and clinoptilolite against zearalenone and ochratoxin A[60,61].However,naturally occurring clays also exert a moderate binding eﬃcacy against mycotoxins,other than aﬂatoxins,as evidenced for zearalenone and ochratoxin A by in vitro[57]andﬁeld trials[62,63],as well as for cyclopiazonic acid in exper-iments with broilers[45].Remarkable conclusions related to zeolitesÕeﬃcacy against zearalenone toxicosis have also been drawn by in vivo studies.Feeding zearalenone to rats,Smith[64] demonstrated that the dietary use of a synthetic anion exchange zeolite could alter the faecal and urinary excre-tory patterns of zearalenone due to the elimination of its intestinal absorption.Recently,the dietary use of a clin-optilolite-rich tuﬀwas also eﬀective in decreasing zearal-enone and a-zearalenole excretion in pigs fed diets contaminated with500ppb zearalenone[65].Addition-ally,in aﬁeld-case of zearalenone toxicosis with mean concentrations of660ppb,Papaioannou et al.[20] reported that the supplementation of a clinoptilolite rich tuﬀat the rate of2%in the ration of pregnant sows im-plied a rather protective role against the consequences of zearalenone ingestion,as evidenced by the improvement of indicative performance traits.Similar results were also obtained in swine with the dietary use of a modiﬁed clinoptilolite–healandite rich tuﬀat0.2%and with zea-ralenone concentration exceeding3.5ppm[66].Apart from surface interactions,the in vivo eﬃcacy of mineral adsorbents against zearalenone could also re-sult from other implicating mechanisms.The entero-he-patic circulation of zearalenone and its derivatives in pigs retards their elimination and enhances the duration of adverse eﬀects[67].Whether certain types of zeolites are able to aﬀect the entero-hepatic cycling of zearale-none,thus counteracting the toxic eﬀects of its biological action,is a hypothesis that awaits further research, although there is evidence of Ca-enriched clinoptiloliteÕs high aﬃnity to the bile acids in the intestinal tract[68].3.Supportive eﬀect on diarrhoea syndromeThere is an abundance of published data which indi-cate that the dietary use of natural zeolites reduces the incidence and decreases the severity and the duration of diarrhoea in calves[1,69–72]and pigs[1,5,13,72–75]. The exact mechanism of zeolitesÕeﬀect is not quite clear so far,although there is evidence that the use of zeolites may eliminate various predisposing and/or causative fac-tors which are associated in the culmination of intestinal disturbances in an interactive way.Apart from zeolitesÕretarding eﬀect on intestinal passage rate[1]and their water adsorption property,which leads to the appear-ance of drier and more compact faeces,as in the case of phillipsite[75]or clinoptilolite[76],Vrzgula et al.[71]also proposed that the ameliorative eﬀect on diar-rhoea syndrome of calves might result from either the alteration of metabolic acidosis,through eﬀects on os-motic pressure in the intestinal lumen,or the increased retention of the enteropathogenic Escherichia coli.As far as we know,there is no evidence in the available lit-erature for retention of enteropathogenic E.coli on the outer surface of zeolite particles.However,clinoptilolite and mordenite are capable to adsorb and partially inac-tivate the thermo-labile(LT)E.coli enterotoxin in vitro, thus constricting its attachment to the intestinalTable2In vivo studies concerning the eﬀect of the dietary use of zeolites during aﬂatoxicosesType of zeolite Dietary inclusion rate(%)Animal model ObservationsClinoptilolite1Broilers Growth depression caused by2.5ppm aﬂatoxin(aﬂ)was alleviated by15%[31] Clinoptilolite5Geese Prophylactic eﬀect on growth rate and liver enzymatic activity[32]Mordenite0.5Broilers Reducing eﬀect on toxicity of aﬂ(3.5mg kgÀ1diet)as indicated byweight gain and changes in uric acid and albumin concentrations[33] Clinoptilolite0.5Weaned piglets Growth inhibitory eﬀects and alterations of liver enzyme activity inducedby500ppb aﬂwere prevented[34]Synthetic zeolite0.5Broilers No signiﬁcant eﬀect on biochemical or haematological indexes whenadministered simultaneously with2.5mg aﬂkgÀ1diet[52]Clinoptilolite0.5Pregnant rats No eﬀect on maternal and developmental toxicities of aﬂ(2mg kgÀ1body weight)[53]Clinoptilolite5Quail chicks Growth inhibitory eﬀects of2mg kgÀ1diet diminished by70%[35] Clinoptilolite 1.5Broilers Growth inhibitory eﬀects of100ppb aﬂdiminished over a studyperiod of42days[36]Clinoptilolite 1.5–2.5Broilers Adverse eﬀects of2.5mg kgÀ1diet on biochemical and haematologicalproﬁles were reduced[54]Zeolite NaA1Broilers Protection against growth inhibitory eﬀects of2.5mg kgÀ1diet[37] Clinoptilolite 1.5–2.5Broilers Moderate to signiﬁcant decrease of incidence and severity of certaintarget-organs degenerative changes induced by2.5mg aﬂkgÀ1diet[55] Clinoptilolite2Laying hens Signiﬁcant decrease in liver mycotoxin concentration and liver weightduring aﬂatoxicosis caused by2.5mg kgÀ1diet[56]D.Papaioannou et al./Microporous and Mesoporous Materials84(2005)161–170163cell-membrane receptors[77].Furthermore,the adsorp-tion capacity of clinoptilolite and mordenite has been proved to be higher than94%for virions of bovine rota-virus and coronavirus,although infectivity level of zeolite–virus complex seems to remain unchanged[78]. Interactions among virions and the outer surface of adsorbent particles have been proposed,since the former have dimensions considerably larger(60–80nm and 60–220nm for rota-and coronavirus particles,respec-tively)than the entry channels of the aforementioned zeolites.In a more recent study of Rodrigues-Fuentes et al.[68],dealing with the development and the properties of an anti-diarrhoeic drug for humans based on clinop-tilolite,zeolite had no eﬀect on rate of passage of inges-ta,neither acted as a water adsorbent.Instead,they proposed that the anti-diarrhoeic eﬀect of clinoptilolite is due to the adsorption of(i)bile acids,‘‘one of the endogenic causes of diarrhoea’’,(ii)aﬂatoxin B1,‘‘a mycotoxin that produces severe toxicity in animals and humans’’and(iii)glucose,‘‘whose high content in intes-tinalﬂuid acts as an irritant factor and whose transport through the intestinal cells is reversed during diarrhoea’’.Concerning the newborn animals,the administration of zeolites appears to reduce the incidence of diarrhoea through the enhancement of passive immunity,as they increase the net absorption of colostrum immunoglobu-lins in calves[71,79,80]and pigs[81].Intestinal hypersensitivity to feed antigens or the mal-absorption syndrome,induced by a low enzyme activity, can both predispose to post-weaning infectious enteritis in pigs.According to Papaioannou et al.[13],clinoptil-olite has the ability to adsorb dietary substances,which may result in intestinal hypersensitivity phenomena[82], or to support the maintenance and even the restoration of the digestive enzyme activity in newly weaned piglets. This should also be evaluated in future studies as an additional explanation for clinoptilolitesÕminimising ef-fect on diarrhoea syndrome.4.Prevention of metabolic diseases in dairy cowsMilk fever and ketosis are of the most common metabolic diseases in high producing dairy cows.In the recent years,a number of experiments have been con-ducted in order to control these diseases using zeolites as feed additives.The results of these experiments are very promising but further investigation is required to deﬁne the exact mechanisms of zeolitesÕaction.k feverInitially,a series of experiments has been conducted in order to study the potential use of synthetic zeolite A for the prevention of milk fever in dairy cows.The objective of these experiments was to reduce the bio-availability of dietary Ca in the gastrointestinal tract by the administration of synthetic zeolite A,based on the evidence that one of the best ways to prevent milk fever is to feed cows with low calcium diets during the dry period[83–87].The results obtained were satisfac-tory as the administration of synthetic zeolite A,either as an oral drench or supplemented to the total mixed ra-tion,during the dry period reduced the bioavailability of dietary Ca and eﬃciently protected against milk fever, by stimulating Ca-homeostatic mechanisms prior to par-turition[88–93].Furthermore,Thilsing-Hansen et al.[92]proposed that the best ratio zeolite/Ca for the pre-vention of milk fever was10–20and that zeolite had the same eﬃciency either administrated for the last4 or2weeks of the dry period.More recently,Katsoulos et al.[94]showed that clin-optilolite was eﬀective in the prevention of milk fever as well.The incidence of milk fever was signiﬁcantly lower in cows that were receiving a concentrate supplemented with clinoptilolite at the level of2.5%(5.9%)during the last month of the dry period and the onset of lactation compared to the animals in the control group(38.9%), which were not receiving clinoptilolite,whereas was not signiﬁcantly diﬀerent than those that were receiving 1.25%clinoptilolite(17.6%)with the concentrates at the same period.The authors suggested that clinoptilolite might have had similar eﬀect with zeolite A in activating Ca homeostatic mechanisms prior to parturition.As a consequence,the animals receiving2.5%clinoptilolite responded faster and more eﬃciently in the drop of serum Ca observed at the day of calving and did not show any clinical signs of milk fever the following days. However,the exact mechanism for this positive eﬀect of clinoptilolite is currently unknown and should be fur-ther investigated.4.2.KetosisThe best strategy to prevent ketosis in dairy cows is to improve the energy uptake both in the dry period and the onset of lactation[95].According to Katsoulos et al.[23],the use of clinoptilolite has been shown to be eﬀective in improving the energy balance at this critical period as they observed that feeding dairy cows on a diet supplemented with clinoptilolite at the level of2.5%of the concentrate feed,resulted in signiﬁcantly lower incidence of ketosis(5.9%)during theﬁrst month after parturition,compared to the control group(38.9%) and the group of the animals receiving a concentrate supplemented with1.25%clinoptilolite(35.3%).These researchers suggested that clinoptilolite improved the energy status of the cows,either via prepartum enhance-ment of propionate production in rumen or through the improvement of the post-ruminal digestion of starch.164 D.Papaioannou et al./Microporous and Mesoporous Materials84(2005)161–1705.Protective role in intoxications and poisonings5.1.Ammonia toxicityWhite and Ohlrogge[96]ﬁrst stated that ammonium ions formed by the enzyme decomposition of non-pro-tein nitrogen were immediately ion exchanged into the zeolite structure and held there for several hours until released by the regenerative action of Na+,entering the rumen in saliva during the after-feeding fermenta-tion period.From both in vitro and in vivo experimentsthey found that up to15%of the NHþ4in the rumencould be taken up by the zeolite.These observations were the causation for the conduction of many experi-ments in order to determine the inﬂuence of zeoliteson rumen NHþ4concentration and their potential usefor the counteraction of the toxic eﬀects of urea inclu-sion in ruminantsÕrations.Hemken et al.[97]showed that supplementation of 6%clinoptilolite,in the ration of dairy cows containing urea,signiﬁcantly reduced rumen NH3concentration. The same trend was observed by the dietary addition of5%clinoptilolite in steers[98]and lambs[99].Fur-thermore,clinoptilolite was eﬀective in reducing rumen ammonia concentration even when no urea was present in the ration of steers receiving a high concentrate diet, and that this reduction was linearly associated to the percentage of clinoptilolite inclusion[100].Nestorov [101]referred that simultaneous administration of clin-optilolite and urea in sheep protects rumenﬂora from toxic eﬀects of ammonia by inhibiting the reduction of microbiota population.In contrast to the former observations,Bergero et al.[102]and Bosi et al.[103]found that daily administration of250g or200g of clinoptilolite, respectively,in dairy cows did not aﬀect rumen NHþ4 concentration.The same result had the dietary inclu-sion of2%synthetic zeolite A in dairy cows ration [104]and5%clinoptilolite in steers receiving a high roughage diet[98].The binding of NHþ4to zeolites has been noted in pigsas well,and many researchers suggested this action as the possible mechanism for the observed improved per-formance of the animals receiving zeolites.There are evi-dences that clinoptilolite elevates nitrogen excretion in feces[8,105]and reduces the ammonia concentration in blood serum[8,10,106],when supplemented to the basal diets of pigs.Furthermore,Pond et al.[10]and Yannakopoulos et al.[12]found that clinoptilolite reduced the weight of the organs involved in the metab-olism of ammonia(liver and kidneys),as the conse-quence of the reduced ammonia concentration in the gastrointestinal tract.Such observations result fromthe direct binding of NHþ4to zeolites,as clinoptilolitehas no adverse eﬀect on the ureolytic bacteria of the large intestine and urease activity[107]anophosphate poisoningThe dietary use of clinoptilolite appears to be eﬀective in the prevention of organophosphates poisoning. Experiments in sheep have shown that the oral adminis-tration of clinoptilolite at the dose of2g/kg of body weight,earlier or simultaneously with an organophos-phate(VX),partially protects from poisoning by inhib-iting the decrease in cholinesterase activity[108]and by protecting rumenﬂora[109].The protective eﬀect of clinoptilolite on cholinesterase activity has been ob-served in mice receiving higher doses of organophos-phates as well[110,111].5.3.Heavy metal toxicity and adsorption of radioactive elementsZeolites,due to their high ion-exchange capacity, have been used eﬀectively for the prevention of heavy metal toxicity in animals.Pond et al.[112]found that clinoptilolite protects growing mice from lead(Pb)tox-icity when added to their ration in such quantities that the ratio clinoptilolite/Pb to be10/1.According to Pond et al.[113],similar protection is provided in swine as well.The selectivity of clinoptilolite for cadmium(Cd) and Pb has been studied in vitro in order to be investi-gated whether its use reduces the levels of these elements in rumen and abomasalﬂuid.The experiments showed that clinoptilolite bent the91%of Pb and the99%of Cd in rumenﬂuid within24h,and in the abomasalﬂuid the94%of Pb within less than1h[114].The toxic eﬀects of long-term ingestion of Cd(100ppm CdCl2)on female rats and their progeny were not diminished by the simul-taneous feeding of a clinoptilolite-rich tuﬀat5%in the diet[115].Adversely,the eﬃcacy of clinoptilolite against Cd toxicity has been proved in pigs by the same authors who observed that3%clinoptilolite supplementation prevented the cadmium-induced iron deﬁcient anemia in growing swine that were receiving150ppm CdCl2 [116].The results of these experiments suggest the feasi-bility of using zeolites and mainly clinoptilolite as a feed additive in the prevention of certain types of heavy metal intoxications in farm animals or in aquatic biolog-ical systems,as is the case in the study of Jain[117], where is ascertained the capacity of zeolite to enhance the removal of Pb from water,thus decreasing its avail-ability to the teleostﬁsh Heteropneustes fossilis.Apart from heavy metals,zeolites can also bind radioactive elements,thus being suggested as a means of altering their uptake and excretion from the body. Zeolitic matrix exchanges radio-nuclides in the gastroin-testinal tract and is excreted by normal processes,there-by eliminating radioactive elementsÕassimilation into the body.Arnek and Forsberg[118]proved the selectiv-ity of some natural zeolites such as clinoptilolite, chabazite and modernite for cesium and GomonajD.Papaioannou et al./Microporous and Mesoporous Materials84(2005)161–170165et al.[119]the selectivity of clinoptilolite for strodium and zirconium.Phillippo et al.[120]showed that the dietary use of clinoptilolite may constitute a simple and cost-eﬀective method for minimizing the adsorption of radioactive cesium by sheep grazing contaminated pastures,although there might be no eﬀect on cesium already been built-up in the body due to a previous exposure.Furthermore,Forsberg et al.[121]observed that the administration of mordenite in sheep and goats increased the excretion of cesium with feces and reduced its accumulation in tissues.On the other hand,Rachu-bik and Kowalski[122]demonstrated that synthetic zeolite-enriched diets exerted an inconsistent pattern of radiostrontium assimilation in the bone tissue and liver or kidneys of rats intragastrically dosed with an aqueous solution of90SrCl2.5.4.Copper toxicityIvan et al.[123]observed that the inclusion of ben-tonite,a phyllosilicate,in the ration of sheep at the rate of0.5%signiﬁcantly reduced the Cu concentration in liver and suggested the use of this material in order to prevent copper poisoning.In contrast,clinoptilolite does not seem to be eﬀective,as Pond[124]found that the addition of2%clinoptilolite to the basal diet of sheep containing10or20ppm Cu did not protect against the toxic signs of Cu and increased the mortality in lambs fed the diet with20ppm Cu.A lack of any ef-fect on liver Cu accumulation was also found in growing pigs which were on diets supplemented with0.5%syn-thetic zeolite A and250ppm Cu[125].Clinoptilolite was expected to exchange Cu in the lumen of the intes-tine,thereby decreasing the toxicity of excess Cu for sheep,whose tolerance for Cu is low compared with that of other food animals.However,such action was not observed probably due to a shift in ion-exchange relativeto Cu and NHþ4or to some other complex interaction,which resulted in a net increase in Cu available for absorption from the intestinal tract[124].The optimum ratio of clinoptilolite to Cu in the diet for reducing the intestinal absorption of the latter has not been deter-mined,but such information,according to Pond[126], is needed in order to establish appropriate levels of die-tary clinoptilolite supplementation.6.Impact on parasite infectionsConsidering the potential eﬃcacy of zeolites against parasite infections,the results of the experimentsﬁrst conducted in rats were encouraging for their use in other animal species as well.According to Wells and McHugh [127],the administration of clinoptilolite at the rate of 10%of a conventional diet facilitated the removal of parasites from the intestinal lumen of rats infected with the nematode Nippostrongylus brasiliensis.Furthermore, Wells and Kilduﬀ[128]observed a more accelerated intestinal a-D-glucosidase and aminopeptidase activity restitution in rats fed a commercial diet supplemented with clinoptilolite(5%)and recovering from N.brasilien-sis infection.Conﬁrming the observations in rats,Deli-giannis et al.[129]recently proved the eﬃcacy of clinoptilolite against parasite infections in growing lambs.They showed that feeding lambs,primarily infected with a single dose of gastrointestinal(GI) nematodes,with a concentrate mixture containing3% clinoptilolite signiﬁcantly decreased their total worm burden and faecal egg counts per capita fecundity and demonstrated that clinoptilolite supplementation re-duced the establishment of GI nematodes and resulted in a good performance of the animals.Interestingly,zeolites have also been tested as anthel-mintic loaded carriers,through retarding drug release and prolonging its therapeutic action.Sustained-release mechanism implies a slow desorption of the drug mole-cules from the external surface and the internal zeolitic cavities,as they are progressively replaced by host pro-teins and water molecules,respectively,during the intes-tinal transport of the drug-zeolite compound.Promising results were obtained,atﬁrst,as regards tetramisole-loaded synthetic zeolite Y[130]and recently,pyrantel-and fenbendazole-loaded synthetic zeolite Y in rats infested with N.brasiliensis and dichlorvos-loaded zeo-lite Y in pigs infected with Ascaris suum[131].In the case of tetramisole and dichlorvos,anthelmintic mole-cules are small enough toﬁt through the entry channels of zeolite Y(windows of7.4A˚),while fenbendazole loading requires an initial partial dealumination of the zeolitic carrier and large pyrantel molecules allow only outer surface loading to occur.7.Prevention of metabolic skeletal defectsThe dietary inclusion of synthetic zeolite A(at the rates of0.75%or1.5%)in broilers which are on a diet with inadequate or marginal levels of calcium results in an increase of bone ash content along with a reduc-tion of rachitic lesions[132].Accordingly,the incorpora-tion of zeolite A in the same diets at1%exerts a clear beneﬁcial eﬀect in reducing the incidence of tibial dys-chondroplasia[132–134].Although tibial dyschondro-plasia is a metabolic cartilage disease which represents the endpoint of several mechanisms,the incidence is in-creased when high dietary levels of phosphorus are used [135]or when dietary calcium is lower than0.85%[136]. Similarly,the beneﬁcial eﬀect of zeolite A is inconsistent and largely depends on the dietary level of calcium. According to Watkins and Southern[137],the dietary use of0.75%zeolite A in broilers is accompanied by alterations in mineral absorption and tissue distribution,166 D.Papaioannou et al./Microporous and Mesoporous Materials84(2005)161–170。

HPLC法测定不同产地柑橘第一次生理落果中活性成分的含量

李阳，安琪，宋悦，等. HPLC 法测定不同产地柑橘第一次生理落果中活性成分的含量[J]. 食品工业科技，2022，43（19）：364−371.doi: 10.13386/j.issn1002-0306.2022010076LI Yang, AN Qi, SONG Yue, et al. Determination of Active Components in the First Physiological Fruit Drop of Citrus from Different Producing Areas by HPLC[J]. Science and Technology of Food Industry, 2022, 43(19): 364−371. (in Chinese with English abstract).doi: 10.13386/j.issn1002-0306.2022010076· 分析检测 ·HPLC 法测定不同产地柑橘第一次生理落果中活性成分的含量李　阳1,2，安　琪1,2，宋　悦1,2，屈沙沙1,2，范　刚1,2, *，任婧楠1,2，潘思轶1,2（1.华中农业大学食品科学技术学院/环境食品学教育部重点实验室，湖北武汉 430070；2.果蔬加工与品质调控湖北省重点实验室（华中农业大学），湖北武汉 430070）摘　要：本研究采用高效液相色谱法（HPLC ）测定我国柑橘主要产区如湖北宜昌、湖南怀化、广东潮州、广西南宁、福建漳州、浙江衢州等地的柑、橙、柚三种柑橘属植物第一次生理落果中川陈皮素、橘皮素、橙皮苷、柚皮苷、柠檬苦素以及辛弗林的含量，比较不同产地柑橘属植物落果中有效活性成分含量的规律特点，旨在选取营养价值高、活性成分含量丰富的柑橘落果品种，为将来从中进一步提取有效成分并将其应用到各方面奠定基础。

结果表明浙江衢州的椪柑落果中川陈皮素及橘皮素含量最高，分别为359.63 μg/g 和222.14 μg/g ；湖北宜昌的蜜柚落果中柚皮苷含量最高，为20.97 mg/g ；湖北宜昌的脐橙落果中橙皮苷含量最高，为1485.73 μg/g ；福建漳州的琯溪蜜柚落果中柠檬苦素含量最高，为866.73 μg/g ；广西南宁的沃柑落果中辛弗林含量最高，为1004.14 μg/g 。

银柴胡多糖超声辅助提取工艺优化及抗氧化活性分析

王红，彭励，宋乐，等. 银柴胡多糖超声辅助提取工艺优化及抗氧化活性分析[J]. 食品工业科技，2024，45（1）：185−191. doi:10.13386/j.issn1002-0306.2023030025WANG Hong, PENG Li, SONG Le, et al. Optimization of Ultrasonic-assisted Extraction Process and Analysis of Antioxidant Activity of Polysaccharide from Stellariae Radix[J]. Science and Technology of Food Industry, 2024, 45(1): 185−191. (in Chinese with English abstract). doi: 10.13386/j.issn1002-0306.2023030025· 工艺技术 ·银柴胡多糖超声辅助提取工艺优化及抗氧化活性分析王　红1，彭　励1,2, *，宋　乐1，冯　璐1，李振凯1，李彦青1，高　跳1（1.宁夏大学生命科学学院，宁夏银川 750021；2.宁夏天然药物工程技术研究中心，宁夏银川 750021）摘　要：目的：为了提高银柴胡多糖得率，对银柴胡多糖提取工艺参数进行优化，并评价其体外抗氧化活性。

方法：采用超声辅助提取银柴胡多糖，在单因素实验基础上结合响应面法（Box–Behnken Response Surface ）对提取工艺参数进行优化，并采用Sevag 法除蛋白得银柴胡粗多糖，进一步对其抗氧化活性进行分析。

结果：优化后银柴胡多糖最佳提取工艺参数为超声温度50 ℃、时间3.20 h 、提取次数2 次，在此条件下多糖得率最高，为28.24%±0.10%，多糖含量为59.13%；体外抗氧化测定结果显示，银柴胡粗多糖清除DPPH 自由基、OH 自由基、ABTS +自由基的IC 50分别是5.47、2.40和1.44 mg/mL ，表明其具有一定的抗氧化能力。

211188544_苹果枸杞酒的研制及挥发性成分分析

许强，蒋晓，谭溪莉，等. 苹果枸杞酒的研制及挥发性成分分析[J]. 食品工业科技，2023，44（10）：151−159. doi: 10.13386/j.issn1002-0306.2022070048XU Qiang, JIANG Xiao, TAN Xili, et al. Development of Apple Lycium barbarum Wine and Analysis of Volatile Components[J].Science and Technology of Food Industry, 2023, 44(10): 151−159. (in Chinese with English abstract). doi: 10.13386/j.issn1002-0306.2022070048· 工艺技术 ·苹果枸杞酒的研制及挥发性成分分析许　强1，蒋　晓1，谭溪莉1，袁天萌1，边名鸿1, *，曾　洪2（1.四川轻化工大学生物工程学院，四川宜宾 644000；2.贵州茅台酒股份有限公司，贵州遵义 564501）摘　要：为增加苹果发酵酒的口感与风味，提升苹果酒的营养价值，以红富士苹果与宁夏枸杞为发酵原料，以总多酚、酒精度及感官品评为主要指标，分别考察安琪果酒酵母（SY ）、和谐A 酵母（LA AROM ）、诺盟B 酵母（LA BAYANUS ）、卓越XR 酵母（EXECLLENCE XR ）、诺盟C 酵母（LA CEREVISIAE ）5株酿酒酵母的发酵能力，并通过单因素实验与正交试验优化苹果枸杞酒发酵工艺，利用气相色谱-质谱联用仪（gas chromatography-mass spectrometry ，GC-MS ）分析检测苹果枸杞酒的挥发性成分。

结果表明，诺盟B 酵母发酵速度最快，发酵所得酒体澄清透亮，香味协调，适合于发酵苹果枸杞酒，其最佳工艺条件为：苹果汁与枸杞汁比例为4:1，初始可溶性固形物10°Brix ，接种量3%，20 ℃发酵6 d ，所得果酒酒精度为5.7%vol ，可溶性固形物为6°Brix ，还原糖含量2.15 g/L ，感官评分为89.6分。

武汉市大气PM 2.5 中多环芳烃的分布特征及来源

( ＩＤ) ꎬ ｄｏｗｎｔｏｗｎａｒｅａ ( ＤＴ) ꎬ ａｎｄｂｏｔａｎｉｃａｌｇａｒｄｅｎｓ ( ＢＧ) . ＴｈｅｓｐａｔｉｏｔｅｍｐｏｒａｌｖａｒｉａｔｉｏｎｓａｎｄｓｏｕｒｃｅｓｏｆＰＡＨｓｗｅｒｅｓｔｕｄｉｅｄｂｙｔｈｅｈｅａｌｔｈ２２�� ８１) ｎｇ∕ｍ３ . Ａｄｄｉｔｉｏｎａｌｌｙꎬ ｔｈｅｃｏｎｃｅｎｔｒａｔｉｏｎｓｏｆＰＡＨｓｅｘｈｉｂｉｔｅｄａｃｌｅａｒｓｅａｓｏｎｐａｔｔｅｒｎａｃｒｏｓｓａｌｌｓｉｔｅｓꎬ ｗｉｔｈｔｈｅｈｉｇｈｅｓｔｖａｌｕｅｓｏｃｃｕｒｒｉｎｇ
收稿日期: ２０１７￣１０￣１２㊀㊀㊀修订日期: ２０１７￣１２￣２１
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李宽ꎬ周家斌ꎬ袁畅ꎬ等. 武汉市大气ＰＭ２�� ５中多环芳烃的分布特征及来源[ Ｊ] . 环境科学研究ꎬ２０１８ꎬ３１(４) :６４８￣６５６. Ｃｉｔｙꎬ Ｃｈｉｎａ[ Ｊ] .ＲｅｓｅａｒｃｈｏｆＥｎｖｉｒｏｎｍｅｎｔａｌＳｃｉｅｎｃｅｓꎬ２０１８ꎬ３１(４) :６４８￣６５６.

211251927_化学修饰多糖的方法及生物活性研究进展

杨艺，赵媛，孙纪录，等. 化学修饰多糖的方法及生物活性研究进展[J]. 食品工业科技，2023，44（11）：468−479. doi:10.13386/j.issn1002-0306.2022070383YANG Yi, ZHAO Yuan, SUN Jilu, et al. Research Progress on Chemical Modification Methods of Polysaccharides and Their Biological Activity[J]. Science and Technology of Food Industry, 2023, 44(11): 468−479. (in Chinese with English abstract). doi:10.13386/j.issn1002-0306.2022070383· 专题综述 ·化学修饰多糖的方法及生物活性研究进展杨　艺1，赵　媛2，孙纪录3，邵娟娟1,*（1.河北农业大学理工学院，河北沧州 061000；2.江南大学化工学院，江苏无锡 214122；3.河北农业大学食品科技学院，河北保定 071000）摘　要：多糖属于生物大分子，其生物活性取决于结构及理化性质。

研究表明，多糖的化学修饰可以使其结构多样性显著增加，提高生物活性，甚至增加新的生物活性。

本文系统综述了近年来化学修饰多糖的研究进展，包括常用的化学修饰方法、各类化学修饰对多糖分子量、理化特性或空间结构的影响、化学修饰多糖的生物活性以及化学修饰多糖在医药和食品工业中的应用前景及挑战，以期为化学修饰多糖的深入研究提供参考建议，同时为未来基于人类健康的食品医药开发提供重要的依据。

关键词：多糖，化学修饰，生物活性，结构，理化性质本文网刊:中图分类号：O629.12 文献标识码：A 文章编号：1002−0306（2023）11−0468−12DOI: 10.13386/j.issn1002-0306.2022070383Research Progress on Chemical Modification Methods ofPolysaccharides and Their Biological ActivityYANG Yi 1，ZHAO Yuan 2，SUN Jilu 3，SHAO Juanjuan 1, *（1.College of Science and Technology, Hebei Agricultural University, Cangzhou 061000, China ；2.School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, China ；3.College of Food Science and Technology, Hebei Agricultural University, Baoding 071000, China ）Abstract ：Polysaccharides are biological macromolecules and their biological activities depend on their structure and physicochemical properties. Studies have shown that chemical modification of polysaccharides can significantly increase their structural diversity, improve their biological activities, and even add new biological activities. This article reviews systematacially the research progress of chemical modification of polysaccharides in recent years, including frequently-used methods of chemical modification, the influence of various chemical modification on molecular weight of polysaccharides,physical and chemical properties and spatial structure, the biological activity of chemically modified polysaccharides as well as their pharmaceutical and food industrial application prospect and challenges. It is expected to offer a reference for the further research chemically modified polysaccharides and provide an important basis for the future development of food and medicine based on human health.Key words ：polysaccharide ；chemical modification ；biological activity ；structure ；physicochemical property近年来，多糖在食品、医药等领域的发展一直是人们关注的热点。

219401794_沙棘果多糖的理化特征及其体外抗氧化活性

赵志强，朱叙丞，冯真颖，等. 沙棘果多糖的理化特征及其体外抗氧化活性[J]. 食品工业科技，2023，44（13）：30−38. doi:10.13386/j.issn1002-0306.2022070288ZHAO Zhiqiang, ZHU Xucheng, FENG Zhenying, et al. Physicochemical Characteristic and Antioxidant Activity in Vitro of Seabuckthorn Fruit Polysaccharide[J]. Science and Technology of Food Industry, 2023, 44(13): 30−38. (in Chinese with English abstract). doi: 10.13386/j.issn1002-0306.2022070288· 研究与探讨 ·沙棘果多糖的理化特征及其体外抗氧化活性赵志强1，朱叙丞1，冯真颖1，陈海婷1，余佳乐1，闫　笛1，宋松泉2，申迎宾1, *，唐翠芳2,*（1.广州大学生命科学学院，广东广州 510006；2.湘南学院南岭现代种业研究院，湖南郴州 423043）摘　要：本研究通过热水提取法从沙棘果实中提取并初步纯化得到一种精制多糖（Seabuckthorn Berry Polysaccha-ride ，SBP ），对其单糖组成、分子量组成、微观表征、热稳定性、流变学特性等理化特征进行表征，并采用四种体外模型评价其抗氧化活性。

结果表明：该多糖的主要组分是一种大分子的酸性多糖，分子量为37.82×104 Da ，由岩藻糖、鼠李糖、阿拉伯糖、半乳糖、葡萄糖、木糖、葡萄糖醛酸等单糖构成，其摩尔比为0.244:0.098:0.265:0.075:0.091:0.081:0.103，含有α、β型糖苷键以及羰基、羧基、醛基、羟基等官能团，具有三螺旋结构，微观结构呈片状。

大蒜多糖提取、结构测定、化学修饰及生物活性研究进展

代爽，李琳琳，尹卫，等. 大蒜多糖提取、结构测定、化学修饰及生物活性研究进展[J]. 食品工业科技，2024，45（1）：9−17. doi:10.13386/j.issn1002-0306.2023060161DAI Shuang, LI Linlin, YIN Wei, et al. Research Progress on Extraction, Structure Determination, Chemical Modification and Biological Activity of Garlic Polysaccharides[J]. Science and Technology of Food Industry, 2024, 45(1): 9−17. (in Chinese with English abstract). doi: 10.13386/j.issn1002-0306.2023060161· 特邀主编专栏—食品中天然产物提取分离、结构表征和生物活性（客座主编：杨栩、彭鑫） ·大蒜多糖提取、结构测定、化学修饰及生物活性研究进展代　爽1,2，李琳琳1,2，尹　卫1，王　乐1，王煜伟1, *，梁　健1,*（1.青海大学省部共建三江源生态与高原农牧业国家重点实验室，青海西宁 810016；2.青海大学农牧学院，青海西宁 810016）摘　要：作为大蒜的主要活性成分之一，大蒜多糖具有增强免疫力、抗菌、抗病毒、抗氧化、保肝、降血脂、降血糖等多种生物活性，应用前景广阔。

大蒜多糖的提取方法以热水法、酶法和超声辅助法最为常见，大蒜多糖是由果糖、葡萄糖、半乳糖、甘露糖、半乳糖醛酸等组成的杂多糖，乙酰化、硒化和磷酸化等化学修饰可以增加大蒜多糖抗氧化等生物活性。

本文从大蒜多糖的提取、结构测定、化学修饰及生物活性的角度出发，系统总结了大蒜多糖的研究现状，未来应关注多糖结构与生物活性的构效关系，深入探讨大蒜多糖的功效机理，以期为大蒜多糖作为功能性产品的开发利用提供理论参考。

海藻酸钠基凝胶球的制备、改性及其食品包装的应用研究进展

杨小叶，马淑凤，王利强. 海藻酸钠基凝胶球的制备、改性及其食品包装的应用研究进展[J]. 食品工业科技，2023，44（24）：376−383. doi: 10.13386/j.issn1002-0306.2023020228YANG Xiaoye, MA Shufeng, WANG Liqiang. Research Progress on Preparation and Modification of Sodium Alginate-based Gel Spheres and Its Application in Food Packaging[J]. Science and Technology of Food Industry, 2023, 44(24): 376−383. (in Chinese with English abstract). doi: 10.13386/j.issn1002-0306.2023020228· 专题综述 ·海藻酸钠基凝胶球的制备、改性及其食品包装的应用研究进展杨小叶1，马淑凤2，王利强1,3,*（1.江南大学机械工程学院，江苏无锡 214122；2.江南大学食品科学与技术学院，江苏无锡 214122；3.江苏省食品先进制造装备技术重点实验室，江苏无锡 214122）摘　要：海藻酸钠是一种天然的多糖材料，具有良好的凝胶特性。

目前利用凝胶特性制备的海藻酸钠基凝胶球主要是作为微胶囊在包封益生菌、细胞与酶的固定、包封精油等方面的应用，但近年来利用海藻酸钠凝胶成球技术包装粘性液体也吸引了众多学者关注，展现出良好的应用前景。

该文概述海藻酸钠凝胶成球形成机理，重点总结海藻酸钠基凝胶球的制备方法及适用范围，包括正向球化法、乳化凝胶法、反向球化法、冷冻反向球化法和同轴挤出法。

由于海藻酸钠基凝胶球的凝胶强度、持水性和包埋率极大影响其应用，故探讨了对海藻酸钠进行复配混合、疏水改性以及对海藻酸钠基凝胶球二次涂膜的改善方法。

芳烃

下，与酰卤（RC0-X）作用，生成芳酮。这个反应是制备芳酮的重要方法之一。
注意：
a.酰基化反应不发生重排，可用克莱门
森法将 -CO- 还原成 -CH2- ，是由苯间
接合成烷基苯的方法。 b.苯环上引入酰基活性下降，不易生成多酰基化产物。 c.苯环上有吸电子基时，不发生酰基化反应。
* 加成反应
② 间位定位基（第二类定位基）
这类定位基可使第二个取代基进入它的间位，常见的有： -N+(CH3)、 -NO2 –CN、 -COOH 、-SO3H 、 -CHO、 -COR 等。特点：a.与苯环相连的原子，一般都是不饱和的（-CCI3 除外）。 b.钝化苯环，难发生取代反应 c.为吸电子基，具有很强的吸电子能力
第六章芳烃(aromatic
hydrocarbon）

第一节芳烃的定义及分类第二节苯的结构第三节单环芳烃第四节稠环芳烃小结
第一节芳烃的定义及分类
芳烃的是芳香族化合物的母体，主要是指分子中含有苯环结构的烃。少数非苯芳烃，虽
不含苯环，但却含有结构、性质与苯环相似的
－O-、－NH2、－NHR、－NR2、－OH、－OCH3、 -NHCOCH3、-OCOR、-C6H5、-CH3、-X 等，定位能力先强后弱。特点： a.与苯环相连的原子一般都是饱和的（-CH=CH2
除外）
b.可活化苯环，比苯易进行亲电取代反应（卤素除外） c.大部分是给电子基（具有给电子性能）
正离子在二氧化硫溶液中作用得到。
环庚三烯正离子的6个π电子
离域分布在7个碳原子上，因此是稳定的，具有芳香性。
●
环辛四烯负离子环辛四烯的π电子数为8，不符合休克尔规

碳包覆的磁性纳米材料萃取酞酸酯

第３２卷㊀第１２期２０１３年㊀㊀１２月环㊀境㊀化㊀学ＥＮＶＩＲＯＮＭＥＮＴＡＬＣＨＥＭＩＳＴＲＹＶｏｌ．３２，Ｎｏ．１２Ｄｅｃｅｍｂｅｒ２０１３㊀２０１３年３月２７日收稿．㊀∗国家自然科学基金（２１２０７０５９，２１１７１０８５）；山东省自然科学基金（ＺＲ２０１０ＢＭ０２７，ＺＲ２０１１ＢＱ０１２）资助．㊀∗∗通讯联系人，Ｔｅｌ：１３８６４５９３６９８；Ｅ⁃ｍａｉｌ：ｌｄｕｚｓｘ＠１２６．ｃｏｍＤＯＩ：１０．７５２４／ｊ．ｉｓｓｎ．０２５４⁃６１０８．２０１３．１２．００３碳包覆的磁性纳米材料萃取酞酸酯∗王颖辉１㊀腾㊀飞２㊀张媛媛３㊀张升晓３∗∗㊀刘军深３㊀吴㊀茜３（１．烟台开发区城市管理环保局，烟台，２６４００６；㊀２．上海通用东岳汽车有限公司，烟台，２６４００６；３．鲁东大学，烟台，２６４０２５）摘㊀要㊀利用水热反应制备碳材料包覆的Ｆｅ３Ｏ４（Ｆｅ３Ｏ４／Ｃ）纳米颗粒，并将这种材料用作固相萃取吸附剂，从环境水样中富集酞酸酯类（ＰＡＥｓ）污染物．由于纳米材料大的比表面积和碳材料强的吸附能力，Ｆｅ３Ｏ４／Ｃ吸附剂拥有较高的萃取效率．从５００ｍＬ的环境水样中定量萃取ＰＡＥｓ目标物，只需５０ｍｇ的吸附剂．ＰＡＥｓ在Ｆｅ３Ｏ４／Ｃ表面的吸附可快速达到平衡，并且用少量的乙腈就能将分析物洗脱下来．在优化的固相萃取条件下，几种ＰＡＥｓ的检出限在１７５８ｎｇ㊃Ｌ－１之间．通过水样的加标回收率来评价该方法，其加标回收率在９４．６％１０６．６％之间，相对标准偏差为２％８％．关键词㊀酞酸酯，磁性固相萃取，碳材料．酞酸酯类化合物（ＰＡＥｓ）作为增塑剂用于塑料制品的生产，来提高塑料强度和增大可塑性．这类物质会从塑料制品中迁移转化进入环境，从而对环境造成污染．ＰＡＥｓ具有三致（致突㊁致畸㊁致癌）作用，属于环境内分泌干扰物，其中有６种化合物已被美国国家环保局列为优先监控污染物［１］．目前测定水体ＰＡＥｓ的前处理方法主要有液液萃取［２］㊁固相萃取［３］㊁固相微萃取［４］等方法．李玫瑰等［５］以甲苯为萃取溶剂，采用微滴液相微萃取方法快速分析水溶性食品中的ＰＡＥｓ．王东新［６］以中空纤维膜液相微萃取方法从天然水体中萃取了４种ＰＡＥｓ，并结合气相色谱进行分析．胡庆兰［７］采用自制的固相微萃取涂层，通过顶空固相微萃取与气相色谱法联用测定水中的ＰＡＥＳ．固相萃取法以有机溶剂消耗少㊁操作简便等优点被广泛采用．王鑫等［８］采用Ｃ１８小柱萃取饮用水和自来水中的４种ＰＡＥｓ类污染物，并用气相色谱法测定．陈永山等［９］研究了流速和除水方式等条件对Ｃ１８固相萃取柱富集ＰＡＥｓ回收率的影响，他们还用罗里硅土净化土壤提取液，测定了土壤中的１１种ＰＡＥｓ类污染物［１０］．纳米材料拥有大的比表面积和短的扩散路径，使其具有很高的萃取效率和较快的吸附速度，近年来被开发研究用作固相萃取吸附剂，从环境或生物样品中富集污染物［１１⁃１２］．然而纳米材料填充的固相萃取小柱具有很大的反压，样品通过小柱需要消耗大量的时间．因此，磁性纳米材料用作固相萃取吸附剂的研究应运而生［１３⁃１５］，张小乐等［１６］合成了Ｃ１８基团修饰的磁性介孔硅胶材料，并利用该材料建立了磁性固相萃取⁃色谱分析方法，测定了环境水样中ＰＡＥｓ污染物的含量．我们以前的研究［１７⁃１９］表明，在基于磁性纳米颗粒的固相萃取方法中，可将经过修饰的磁性纳米材料分散到样品中进行目标物吸附，达到吸附平衡后，利用磁铁快速将吸附了目标物的磁性材料分离出来，然后将目标物进行洗脱㊁测定，该快速磁分离方法避免了传统固相萃取中耗时的过柱操作，能够节省大量时间．本文制备了一种新型的磁性纳米材料（Ｆｅ３Ｏ４／Ｃ），并以该纳米材料为固相萃取吸附剂从环境水样中富集ＰＡＥｓ污染物．优化了吸附剂用量㊁平衡时间㊁盐度㊁ｐＨ㊁解吸附等固相萃取条件，并将这种新型的固相萃取技术与高效液相色谱（ＨＰＬＣ）结合，开发了一种分析环境水体中ＰＡＥｓ的新方法．１㊀实验部分１．１㊀化学试剂和材料㊀㊀酞酸丙酯（ＤＰＰ）㊁酞酸丁酯（ＤＢＰ）㊁酞酸环己酯（ＤＣＰ）和酞酸辛酯（ＤＯＰ）标准样品从美国Ａｃｒｏｓ２２４４㊀环㊀㊀境㊀㊀化㊀㊀学３２卷Ｏｒｇａｎｉｃｓ公司购得．十八烷基三乙氧基硅烷购买自日本东京化学试剂公司．ＦｅＣｌ３㊃４Ｈ２Ｏ和ＦｅＣｌ２㊃６Ｈ２Ｏ从北京化学试剂公司购买．葡萄糖购买自北京红星化学公司．色谱纯的甲醇和乙腈购自美国的ＴｈｅｒｍｏＦｉｓｈｅｒ公司．实验用的纯水来自于美国Ｍｉｌｌｉ⁃Ｑ纯水系统．１．２㊀Ｆｅ３Ｏ４和Ｆｅ３Ｏ４／Ｃ纳米材料的制备和表征采用化学共沉淀的方法制备Ｆｅ３Ｏ４磁性纳米材料．首先将２．０ｇＦｅＣｌ２㊃４Ｈ２Ｏ和５．２ｇＦｅＣｌ３㊃６Ｈ２Ｏ溶解到２５ｍＬ的预先脱氧的去离子水，再加入０．８５ｍＬ浓盐酸．将以上溶液逐滴加到２５０ｍＬ１．５ｍｏｌ㊃Ｌ－１的ＮａＯＨ溶液，边加边机械搅拌并通氮气保护．反应完成后，生成的黑色Ｆｅ３Ｏ４纳米颗粒用２００ｍＬ去离子水洗２次，再分散到１１０ｍＬ的去离子水中，悬浮液中Ｆｅ３Ｏ４纳米颗粒的浓度约为２０ｍｇ㊃ｍＬ－１．采用水热法在纳米Ｆｅ３Ｏ４的表面包覆一层碳材料．将０．４ｇＦｅ３Ｏ４用去离子水冲洗，直至溶液为中性，然后分散到８０ｍＬ０．５ｍｏｌ㊃Ｌ－１的葡萄糖溶液中，将此混合物超声２０ｍｉｎ后转移到聚四氟乙烯内衬的反应釜中．将反应釜在１８０ħ加热４ｈ，反应完成后，用磁铁将Ｆｅ３Ｏ４／Ｃ纳米材料分离，再用去离子水和乙醇冲洗几次除去杂质．最后将反应产物分散到７０ｍＬ的去离子水中得到１０ｍｇ㊃ｍＬ－１的Ｆｅ３Ｏ４／Ｃ．利用透射电镜（ＴＥＭ，Ｈ⁃７５００，Ｈｉｔａｃｈｉ，Ｊａｐａｎ）观察制得的吸附材料的形貌和粒径，工作电压为８０ｋＶ．材料的能谱图（ＥＤＳ）采用Ｓ⁃３０００Ｎ能谱仪（Ｈｉｔａｃｈｉ，Ｊａｐａｎ）测定．材料的红外谱图采用ＫＢｒ压片的方式在ＮＥＸＵＳ６７０傅立叶变换红外光谱仪（ＮｉｃｏｌｅｔＴｈｅｒｍｏ，Ｕ．Ｓ．）采集．１．３㊀固相萃取的程序将５０ｍｇ的Ｆｅ３Ｏ４／Ｃ吸附剂分散到５００ｍＬ水样中，搅拌２０ｓ使吸附剂在溶液中均匀分散．将１个Ｎｄ⁃Ｆｅ⁃Ｂ强力磁铁置于容器底部进行磁分离．经过大约１０ｍｉｎ，溶液变清澈，吸附剂被完全分离到容器底部，将上清液倒掉．在吸附剂中加入２ｍＬ乙腈，超声１０ｓ后置于磁铁上分离，洗脱液转移到离心管中，取２０μＬ进ＨＰＬＣ系统测定．由于塑料制品可能会释放出ＰＡＥｓ，因此在实验过程中使用玻璃容器．１．４㊀ＨＰＬＣ分析利用美国安捷伦公司的高效液相色谱系统对ＰＡＥｓ进行分离和分析，迪马Ｃ１８色谱柱（２５０ˑ４．６ｍｍ，粒径５μｍ），采用梯度淋洗的方法分离，５０％的乙腈水溶液和纯乙腈分别为流动相Ａ和Ｂ，流速为１ｍＬ㊃ｍｉｎ－１．梯度淋洗程序如下：前１５ｍｉｎ内Ｂ保持在４０％，在１０ｍｉｎ内Ｂ由４０％升至１００％，保持１０ｍｉｎ，随后在３ｍｉｎ内回到初始状态．ＰＡＥｓ采用紫外检测器测定，波长设在２２６ｎｍ．２㊀结果与讨论２．１㊀吸附剂的表征图１为Ｆｅ３Ｏ４和Ｆｅ３Ｏ４／Ｃ的透射电镜图片．Ｆｅ３Ｏ４纳米颗粒为近似球形，粒径分布比较均匀，平均直径大约为１０ｎｍ．Ｆｅ３Ｏ４／Ｃ纳米颗粒呈现出明显的核壳结构，内层颜色较深的为Ｆｅ３Ｏ４核，而外层颜色相对较浅的部分是碳层．Ｆｅ３Ｏ４核使得材料具有磁性，而碳包覆层赋予材料强的吸附能力．图１㊀Ｆｅ３Ｏ４（ａ）和Ｆｅ３Ｏ４／Ｃ（ｂ）纳米材料的透射电镜图（放大倍数：２０００００）Ｆｉｇ．１㊀ＴＥＭｉｍａｇｅｓｏｆＦｅ３Ｏ４（ａ），ａｎｄＦｅ３Ｏ４／Ｃ（ｂ）ｎａｎｏｐａｒｔｉｃｌｅ㊀１２期王颖辉等：碳包覆的磁性纳米材料萃取酞酸酯２２４５㊀Ｆｅ３Ｏ４和Ｆｅ３Ｏ４／Ｃ的能谱图见图２．在Ｆｅ３Ｏ４纳米颗粒的能谱图中只有一个很小的碳峰，在其表面包覆一层碳材料后，Ｆｅ３Ｏ４／Ｃ的能谱图中出现了一个较大的碳峰，其表面碳元素的摩尔百分含量达到５４４％，而铁元素的摩尔百分含量降低到１３．８％，说明碳材料被成功的包覆到了Ｆｅ３Ｏ４纳米颗粒表面．图２㊀Ｆｅ３Ｏ４（ａ）和Ｆｅ３Ｏ４／Ｃ（ｂ）纳米材料的能谱图Ｆｉｇ．２㊀ＥＤＳｓｐｅｃｔｒａｏｆＦｅ３Ｏ４（ａ）ａｎｄＦｅ３Ｏ４／Ｃ（ｂ）ｎａｎｏｐａｒｔｉｃｌｅ利用傅立叶变换红外光谱分析Ｆｅ３Ｏ４和Ｆｅ３Ｏ４／Ｃ材料的表面基团．由图３可见，Ｆｅ３Ｏ４和Ｆｅ３Ｏ４／Ｃ的红外谱图上都有１个５８０ｃｍ－１的吸收峰，为Ｆｅ３Ｏ４的特征吸收峰［２０］．在Ｆｅ３Ｏ４／Ｃ的谱图上１７００ｃｍ－１和１６１６ｃｍ－１的峰是ＣＯ和ＣＣ的振动吸收峰［２１］，这表明在水热反应的过程中，葡萄糖碳化包覆到了纳米Ｆｅ３Ｏ４的表面．１０００１３００ｃｍ－１的峰是ＣＯＨ的伸缩振动峰和ＯＨ弯曲振动峰［２２］，３１００３７００ｃｍ－１之间的宽峰是ＯＨ伸缩振动峰［２３］．Ｆｅ３Ｏ４／Ｃ纳米材料的表面上羟基和羧基基团的存在使得该材料具有表面亲水性，能够在水溶液中分散和稳定存在，并且材料的表面亲水性降低了分析物在其表面的不可逆吸附，能够在一定程度上克服碳材料用作固相萃取洗脱困难的缺点．２．２㊀萃取条件的优化２．２．１㊀吸附剂用量的选择为了获得最优的目标物回收率，在０１００ｍｇ的范围改变Ｆｅ３Ｏ４／Ｃ吸附材料的加入量进行萃取，其结果列于图４．随Ｆｅ３Ｏ４／Ｃ吸附剂加入量的增加，ＰＡＥｓ的回收率也逐渐增加，当吸附剂用量为４０ｍｇ时，ＰＡＥｓ的回收率达到最大值，吸附剂的用量继续增加，回收率基本保持平衡，不会再有明显的增加．使用没有修饰的Ｆｅ３Ｏ４作为固相萃取的吸附剂，即使其用量达到１００ｍｇ，对ＰＡＥｓ的回收率也不会超过１０％．图３㊀Ｆｅ３Ｏ４和Ｆｅ３Ｏ４／Ｃ纳米材料的红外谱图Ｆｉｇ．３㊀ＩＲｓｐｅｃｔｒａｏｆＦｅ３Ｏ４ａｎｄＦｅ３Ｏ４／Ｃｎａｎｏｐａｒｔｉｃｌｅ图４㊀吸附剂用量对ＰＡＥｓ回收率的影响Ｆｉｇ．４㊀ＥｆｆｅｃｔｏｆｔｈｅａｍｏｕｎｔｏｆＦｅ３Ｏ４／ＣｓｏｒｂｅｎｔｏｎｔｈｅｅｘｔｒａｃｔｉｏｎｅｆｆｉｃｉｅｎｃｙｏｆＰＡＥｓ㊀㊀结果表明，能够有效吸附ＰＡＥｓ的是Ｆｅ３Ｏ４／Ｃ材料表面的碳层．碳纳米管和有机化合物之间的吸附主要通过疏水作用，π⁃π键㊁氢键作用和静电作用［２４］，Ｆｅ３Ｏ４／Ｃ纳米颗粒表面也是碳材料，因此其相互２２４６㊀环㊀㊀境㊀㊀化㊀㊀学３２卷作用机理相同．要达到满意的回收率只需要Ｆｅ３Ｏ４／Ｃ吸附剂４０ｍｇ，可能是因为Ｆｅ３Ｏ４／Ｃ材料拥有大的比表面积和碳材料的强吸附能力．为保证分析物的完全吸附，在水样中加入５０ｍｇ的Ｆｅ３Ｏ４／Ｃ纳米吸附剂．２．２．２㊀乙腈用量和平衡时间的选择选用乙腈从Ｆｅ３Ｏ４／Ｃ吸附剂上解吸ＰＡＥｓ．为了能够将ＰＡＥｓ充分解吸附，将Ｆｅ３Ｏ４／Ｃ吸附剂在洗脱液中超声２０ｓ再分离．由图５（ａ）可以看出，只需１ｍＬ乙腈就可将８０％以上的目标物解吸下来，增加乙腈的用量，ＰＡＥｓ的回收率略有增加，但影响不大，本实验选用２ｍＬ乙腈作为洗脱剂．传统的碳材料用作固相萃取吸附剂时，常常面临洗脱困难的问题［２５］．而本研究中Ｆｅ３Ｏ４／Ｃ材料较易洗脱，一方面可能是因为包覆在纳米材料上的薄层碳使得分析物的扩散路径较短，便于洗脱，另一方面可能是因为包覆上的碳材料表面是亲水性，有效避免了分析物在其上发生不可逆吸附．Ｆｅ３Ｏ４／Ｃ是超顺磁性并且拥有大的饱和磁强度，但由于其在水溶液中分散良好且表面羧基使颗粒之间存在静电斥力，因此从纯水中用磁铁分离需要较长时间．为了帮助磁分离，在水溶液中加入２ｍＬ１ｍｏｌ㊃Ｌ－１的ＮａＣｌ溶液提供补偿离子．用一个Ｎｄ⁃Ｆｅ⁃Ｂ强力磁铁能在１０ｍｉｎ将吸附剂完全吸附到容器的底部．通常要达到完全吸附目标物和吸附剂要有充分的接触时间．改变平衡时间考察目标物回收率的变化，由图５（ｂ）可以看出，随着平衡时间由０到１２０ｍｉｎ，ＰＡＥｓ的回收率没有明显变化，说明分析物能在很短的时间内完全吸附到Ｆｅ３Ｏ４／Ｃ材料上．这种快的吸附速率应归功于纳米材料短的扩散路径．磁性分离和快速的吸附，使这种新型固相萃取方法能够避免耗时的过柱操作，具有可操作性和实用性．图５㊀洗脱液乙腈用量（ａ）和平衡时间（ｂ）对ＰＡＥｓ回收率的影响Ｆｉｇ．５㊀Ｅｆｆｅｃｔｏｆａｃｅｔｏｎｉｔｒｉｌｅｖｏｌｕｍｅ（ａ）ａｎｄｓｔａｎｄｉｎｇｔｉｍｅ（ｂ）ｏｎｔｈｅｒｅｃｏｖｅｒｙｏｆＰＡＥｓ２．２．３㊀盐度和ｐＨ的选择为了考察盐度对ＰＡＨｓ回收率的影响，在溶液中加入ＮａＣｌ调整盐度．由图６（ａ）可以看出，在盐度为１５００ｍｍｏｌ㊃Ｌ－１的范围内，目标物的回收率基本不受影响，表明Ｆｅ３Ｏ４／Ｃ能从高盐度水样中萃取目标物而不受影响．吸附剂表面电荷的类型和密度通常会随溶液ｐＨ的改变而变化，因此溶液的ｐＨ可能会影响一些分析物在Ｆｅ３Ｏ４／Ｃ纳米材料上的吸附．改变溶液的ｐＨ值在３１０范围内考察其对ＰＡＨｓ萃取回收率的影响．由图６（ｂ）可以看出，在设定的ｐＨ范围内ＰＡＥｓ的回收率没有明显变化，说明Ｆｅ３Ｏ４／Ｃ纳米材料在此ｐＨ范围内比较稳定，不会被破坏，另一方面可能是因为ＰＡＥｓ在设定的条件以中性分子形式存在，材料表面电荷的改变对它们的吸附没有明显的影响．基于Ｆｅ３Ｏ４／Ｃ的磁性固相萃取方法无需严格控制溶液ｐＨ，用于环境水样品的分析更加便利和稳定．２．２．４㊀水样体积选择利用Ｆｅ３Ｏ４／Ｃ作吸附剂进行固相萃取，可以将材料分散在溶液中进行吸附，达到吸附平衡后用磁铁将吸附剂分离出来进行洗脱，该方法免去了耗时的过柱操作，因此非常适用于大体积环境水样的分析．如图７所示，利用５０ｍｇＦｅ３Ｏ４／Ｃ吸附剂，当水样的体积由２００ｍＬ增加到１０００ｍＬ时，ＰＡＨｓ的回收率没有明显下降，说明Ｆｅ３Ｏ４／Ｃ吸附材料具有大的穿透体积．通过从１０００ｍＬ水样中萃取目标物并将洗脱液浓缩到２ｍＬ，ＰＡＥｓ的富集系数可以达到５００倍．㊀㊀１２期王颖辉等：碳包覆的磁性纳米材料萃取酞酸酯２２４７图６㊀盐度（ａ）和溶液ｐＨ值（ｂ）对ＰＡＥｓ回收率的影响Ｆｉｇ．６㊀Ｅｆｆｅｃｔｏｆｓａｌｉｎｉｔｙ（ａ）ａｎｄｓｏｌｕｔｉｏｎｐＨ（ｂ）ｏｎｔｈｅｅｘｔｒａｃｔｉｏｎｅｆｆｉｃｉｅｎｃｙｏｆＰＡＥｓ图７㊀水样体积对ＰＡＥｓ回收率的影响Ｆｉｇ．７㊀ＥｆｆｅｃｔｏｆｗａｔｅｒｓａｍｐｌｅｖｏｌｕｍｅｏｎｔｈｅｒｅｃｏｖｅｙｏｆＰＡＥｓ２．３㊀分析方法相关参数固相萃取程序结合ＨＰＬＣ⁃ＵＶ检测建立了标准曲线，其线性范围为０．１２０ｎｇ㊃ｍＬ－１．从５００ｍＬ纯水样品中萃取目标物并用２ｍＬ溶剂洗脱，ＰＡＥｓ的富集系数为２５０倍．线性范围㊁线性相关系数和检出限等参数列于表１．由表１可以看出，该方法有较高的灵敏度㊁宽的线性范围和良好的精密度，ＰＡＥｓ的线性相关系数Ｒ２＞０．９９９．ＤＰＰ㊁ＤＢＰ㊁ＤＣＰ㊁ＤＯＰ的检出限（信噪比为３）分别为３５㊁５８㊁１７㊁３３ｎｇ㊃Ｌ－１．表１㊀标准曲线的方法参数Ｔａｂｌｅ１㊀Ａｎａｌｙｔｉｃａｌｐａｒａｍｅｔｅｒｓｏｆｔｈｅｐｒｏｐｏｓｅｄｍｅｔｈｏｄ分析物线性范围／（ｎｇ㊃ｍＬ－１）曲线方程线性相关系数（Ｒ２）方法检出限ａ／（ｎｇ㊃Ｌ－１）ＤＰＰ０．１２０ｙ＝０．５５７８ｘ＋０．０５６１０．９９９８３５ＤＢＰ０．１２０ｙ＝０．５４７６ｘ＋０．０６３４０．９９９７５８ＤＣＰ０．１２０ｙ＝０．９８６５ｘ－０．０３２７０．９９９７１７ＤＯＰ０．１２０ｙ＝０．５９４８ｘ＋０．１０３６０．９９９９３３㊀㊀ａ检测限根据信噪比为３确定（Ｓ／Ｎ＝３），ｘ为分析物浓度，ｙ为紫外信号强度．２．４㊀实际水样的测定实际水样选取实验室自来水和校园人工湖的湖水，采用所建立的磁性固相萃取方法测定水样中和加标后的水样中的ＰＡＥｓ，３次平行测定水样和加标水样结果平均值㊁加标水样的回收率平均值及标准偏差列于表２．自来水样中ＤＰＰ浓度为０．１０４ｎｇ㊃ｍＬ－１，其他未检出；湖水中ＤＰＰ和ＤＢＰ浓度分别为０２１５和０．１３２ｎｇ㊃ｍＬ－１，其余未检出．水样中低浓度的ＰＡＥｓ可能来自于塑料管路或者是塑料制品的释放．加标水样中ＰＡＥｓ的平均回收率在９４．６％１０６．６％之间，相对标准偏差为２％８％．图８为湖水样品及其加标色谱图，其峰型良好，基质相对比较干净，没有太多杂峰的干扰．２２４８㊀环㊀㊀境㊀㊀化㊀㊀学３２卷表２㊀实际水样中ＰＡＥｓ的浓度及其加标回收结果Ｔａｂｌｅ２㊀ＣｏｎｃｅｎｔｒａｔｉｏｎｓｏｆＰＡＥｓｉｎｒｅａｌｗａｔｅｒｓａｍｐｌｅｓａｎｄｒｅｃｏｖｅｒｉｅｓｏｆｓａｍｐｌｅｓｓｐｉｋｅｄｗｉｔｈａｎａｌｙｔｅｓ水样加标／（ｎｇ㊃ｍＬ－１）测定值ａ／（ｎｇ㊃ｍＬ－１）ＤＰＰＤＢＰＤＣＰＤＯＰ回收率ʃ相对标准偏差／％ｂＤＰＰＤＢＰＤＣＰＤＯＰ０．０００．１０４ｎｄｃｎｄｎｄ自来水０．５０．６１２０．５０４０．５２４０．５３３１０１．６ʃ３１０１．０ʃ２１０４．８ʃ６１０６．６ʃ８５５．１５５．１０４．８６４．７９１００．９ʃ２１０２．０ʃ４９７．２ʃ４９５．８ʃ７０．０００．２１５０．１３２ｎｄｎｄ湖水０．５０．７４５０．６５３０．５２３０．４９２１０６．０ʃ７１０４．２ʃ６１０４．６ʃ７９８．４ʃ４５４．９５４．９６４．７３４．８４９４．７ʃ６９６．６ʃ５９４．６ʃ７９６．８ʃ６㊀㊀注：ａ３次平行测定结果．ｂ３次测定相对标准偏差．ｃｎｄ未检出．图８㊀湖水样品中ＰＡＥｓ的色谱图．湖水样品（ａ），湖水加标０．５ｎｇ㊃ｍＬ－１（ｂ）和５ｎｇ㊃ｍＬ－１（ｃ）Ｆｉｇ．８㊀ＨＰＬＣ⁃ＵＶｃｈｒｏｍａｔｏｇｒａｍｓｏｆｌａｋｅｗａｔｅｒ（ａ），ａｎｄｉｔｓｓｐｉｋｅｄｓａｍｐｌｅｓｗｉｔｈ０．５ｎｇ㊃ｍＬ－１（ｂ）ａｎｄ５ｎｇ㊃ｍＬ－１（ｃ）ｏｆｅａｃｈａｎａｌｙｔｅ３㊀结论制备了超顺磁性的Ｆｅ３Ｏ４／Ｃ吸附剂，并用其从大体积环境水样中富集痕量的ＰＡＥｓ污染物．与传统的和文献报道的固相萃取方法比较，该方法具有如下优点：（ａ）超顺磁性吸附剂可以直接分散到水样中吸附目标物，达到吸附平衡后用磁铁分离洗脱，磁分离方法避免了耗时的过柱操作．（ｂ）Ｆｅ３Ｏ４／Ｃ具有纳米材料大的比表面积和碳材料强的吸附能力，因此从大体积水样中萃取目标物只需要少量吸附剂就能获得满意的结果．（ｃ）目标物的回收率不受溶液盐度和ｐＨ值的影响，因此在萃取时不需要对水样进行繁琐的调整．（ｄ）Ｆｅ３Ｏ４／Ｃ吸附剂的制备方法简单，所用试剂价格低廉，无毒．在进行萃取的过程中不会在环境水样中引入有毒有害的物质，环境友好．参㊀考㊀文㊀献［１］㊀王红芬，程晗煜，洪坚平．环境中酞酸酯的污染现状及防治措施［Ｊ］．环境科学与管理，２０１０，３５（７）：３３⁃３６［２］㊀ＣａｉＹＱ，ＣａｉＹＥ，ＳｈｉＹＬ，ｅｔａｌ．Ａｌｉｑｕｉｄ⁃ｌｉｑｕｉｄｅｘｔｒａｃｔｉｏｎｔｅｃｈｎｉｑｕｅｆｏｒｐｈｔｈａｌａｔｅｅｓｔｅｒｓｗｉｔｈｗａｔｅｒ⁃ｓｏｌｕｂｌｅｏｒｇａｎｉｃｓｏｌｖｅｎｔｓｂｙａｄｄｉｎｇｉｎｏｒｇａｎｉｃｓａｌｔｓ［Ｊ］．ＭｉｃｒｏｃｈｉｍｉｃａＡｃｔａ，２００７，１５７：７３⁃７９［３］㊀王超英，李碧芳，李攻科．固相微萃取／高效液相色谱联用分析水中邻苯二甲酸酯［Ｊ］．分析测试学报，２００５，２４（５）：３５⁃３８［４］㊀ＰｅñａｌｖｅｒＡ，ＰｏｃｕｒｌｌＥ，ＢｏｒｒｕｌｌＦ，ｅｔａｌ．Ｄｅｔｅｒｍｉｎａｔｉｏｎｏｆｐｈｔｈａｌａｔｅｅｓｔｅｒｓｉｎｗａｔｅｒｓａｍｐｌｅｓｂｙｓｏｌｉｄ⁃ｐｈａｓｅｍｉｃｒｏｅｘｔｒａｃｔｉｏｎａｎｄｇａｓｃｈｒｏｍａｔｏｇｒａｐｈｙｗｉｔｈｍａｓｓｓｐｅｃｔｒｏｍｅｔｒｉｃｄｅｔｅｃｔｉｏｎ［Ｊ］．ＪＣｈｒｏｍａｔｏｇｒＡ，２０００，８７２：１９１⁃２０１［５］㊀李玫瑰，李元星，毛丽秋．微滴液相微萃取技术用于气相色谱⁃质谱法测定食品中的酞酸酯［Ｊ］．色谱，２００７，２５（１）：３５⁃３８［６］㊀王东新．中空纤维液相微萃取⁃气相色谱测定不同天然水体中的酞酸酯类化合物［Ｊ］．南京师范大学学报（工程技术版），２００８，８（３）：４３⁃４６［７］㊀胡庆兰．自制固相微萃取涂层同时测定水中的多环芳烃和酞酸酯［Ｊ］．吉林大学学报（理学版），２０１３，５１（２）：３１７⁃３２０［８］㊀王鑫，许小苗，俞晔，等．固相萃取⁃气相色谱法同时测定水中的酞酸酯类环境激素［Ｊ］．食品工业科技，２００８，２９（４）：２８７⁃２８９［９］㊀陈永山，骆永明，章海波，等．固相萃取法处理环境水样中酞酸酯：流速与除水方式的影响［Ｊ］．环境化学，２０１０，２９（５）：９５４⁃９５９［１０］㊀黄玉娟，陈永山，骆永明，等．气相色谱⁃质谱联用内标法测定土壤中１１种酞酸酯［Ｊ］．环境化学，２０１３，３２（４）：６５８⁃６６５㊀㊀１２期王颖辉等：碳包覆的磁性纳米材料萃取酞酸酯２２４９［１１］㊀ＣａｉＹＱ，ＪｉａｎｇＧＢ，ＬｉｕＪＦ，ｅｔａｌ．Ｍｕｌｔｉｗａｌｌｅｄｃａｒｂｏｎｎａｎｏｔｕｂｅｓａｓａｓｏｌｉｄ⁃ｐｈａｓｅｅｘｔｒａｃｔｉｏｎａｄｓｏｒｂｅｎｔｆｏｒｔｈｅｄｅｔｅｒｍｉｎａｔｉｏｎｏｆｂｉｓｐｈｅｎｏｌＡ，４⁃ｎ⁃Ｎｏｎｙｌｐｈｅｎｏｌ，ａｎｄ４⁃ｔｅｒｔ⁃Ｏｃｔｙｌｐｈｅｎｏｌ［Ｊ］．ＡｎａｌＣｈｅｍ，２００３，７５：２５１７⁃２５２１［１２］㊀ＷａｎｇＨＹ，ＣａｍｐｉｇｌｉａＡＤ．Ｄｅｔｅｒｍｉｎａｔｉｏｎｏｆｐｏｌｙｃｙｃｌｉｃａｒｏｍａｔｉｃｈｙｄｒｏｃａｒｂｏｎｓｉｎｄｒｉｎｋｉｎｇｗａｔｅｒｓａｍｐｌｅｓｂｙｓｏｌｉｄ⁃ｐｈａｓｅｎａｎｏｅｘｔｒａｃｔｉｏｎａｎｄｈｉｇｈ⁃ｐｅｒｆｏｒｍａｎｃｅｌｉｑｕｉｄｃｈｒｏｍａｔｏｇｒａｐｈｙ［Ｊ］．ＡｎａｌＣｈｅｍ，２００８，８０：８２０２⁃８２０９［１３］㊀ＺｈａｏＸＬ，ＳｈｉＹＬ，ＣａｉＹＱ，ｅｔａｌ．Ｃｅｔｙｌｔｒｉｍｅｔｈｙｌａｍｍｏｎｉｕｍｂｒｏｍｉｄｅ⁃ｃｏａｔｅｄｍａｇｎｅｔｉｃｎａｎｏｐａｒｔｉｃｌｅｓｆｏｒｔｈｅｐｒｅｃｏｎｃｅｎｔｒａｔｉｏｎｏｆｐｈｅｎｏｌｉｃｃｏｍｐｏｕｎｄｓｆｒｏｍｅｎｖｉｒｏｎｍｅｎｔａｌｗａｔｅｒｓａｍｐｌｅｓ［Ｊ］．ＥｎｖｉｒｏｎＳｃｉＴｅｃｈｎｏｌ，２００８，４２：１２０１⁃１２０６［１４］㊀ＺｈａｏＸＬ，ＳｈｉＹＬ，ＷａｎｇＴ，ｅｔａｌ．Ｐｒｅｐａｒａｔｉｏｎｏｆｓｉｌｉｃａ⁃ｍａｇｎｅｔｉｔｅｎａｎｏｐａｒｔｉｃｌｅｍｉｘｅｄｈｅｍｉｍｉｃｅｌｌｅｓｏｒｂｅｎｔｓｆｏｒｅｘｔｒａｃｔｉｏｎｏｆｓｅｖｅｒａｌｔｙｐｉｃａｌｐｈｅｎｏｌｉｃｃｏｍｐｏｕｎｄｓｆｒｏｍｅｎｖｉｒｏｎｍｅｎｔａｌｗａｔｅｒｓａｍｐｌｅｓ［Ｊ］．ＪＣｈｒｏｍａｔｏｇｒＡ，２００８，１１８８：１４０⁃１４７［１５］㊀ＬｉＪＤ，ＺｈａｏＸＬ，ＳｈｉＹＬ，ｅｔａｌ．Ｍｉｘｅｄｈｅｍｉｍｉｃｅｌｌｅｓｓｏｌｉｄ⁃ｐｈａｓｅｅｘｔｒａｃｔｉｏｎｂａｓｅｄｏｎｃｅｔｙｌｔｒｉｍｅｔｈｙｌａｍｍｏｎｉｕｍｂｒｏｍｉｄｅ⁃ｃｏａｔｅｄｎａｎｏ⁃ｍａｇｎｅｔｓＦｅ３Ｏ４ｆｏｒｔｈｅｄｅｔｅｒｍｉｎａｔｉｏｎｏｆｃｈｌｏｒｏｐｈｅｎｏｌｓｉｎｅｎｖｉｒｏｎｍｅｎｔａｌｗａｔｅｒｓａｍｐｌｅｓｃｏｕｐｌｅｄｗｉｔｈｌｉｑｕｉｄｃｈｒｏｍａｔｏｇｒａｐｈｙ／ｓｐｅｃｔｒｏｐｈｏｔｏｍｅｔｒｙｄｅｔｅｃｔｉｏｎ［Ｊ］．ＪＣｈｒｏｍａｔｏｇｒＡ，２００８，１１８０：２４⁃３１［１６］㊀张小乐，王巍杰，张一江，等．磁性介孔硅胶萃取剂的制备及萃取性能研究［Ｊ］．环境化学，２０１２，３１（４）：４２２⁃４２８［１７］㊀ＺｈａｎｇＳＸ，ＮｉｕＨＹ，ＣａｉＹＱ，ｅｔａｌ．ＢａｒｉｕｍａｌｇｉｎａｔｅｃａｇｅｄＦｅ３Ｏ４＠Ｃ１８ｍａｇｎｅｔｉｃｎａｎｏｐａｒｔｉｃｌｅｓｆｏｒｔｈｅｐｒｅ⁃ｃｏｎｃｅｎｔｒａｔｉｏｎｏｆｐｏｌｙｃｙｃｌｉｃａｒｏｍａｔｉｃｈｙｄｒｏｃａｒｂｏｎｓａｎｄｐｈｔｈａｌａｔｅｅｓｔｅｒｓｆｒｏｍｅｎｖｉｒｏｎｍｅｎｔａｌｗａｔｅｒｓａｍｐｌｅｓ［Ｊ］．ＡｎａｌＣｈｉｍＡｃｔａ，２０１０，６６５：１６７⁃１７５［１８］㊀ＺｈａｎｇＳＸ，ＮｉｕＨＹ，ＨｕＺＪ，ｅｔａｌ．ＰｒｅｐａｒａｔｉｏｎｏｆｃａｒｂｏｎｃｏａｔｅｄＦｅ３Ｏ４ｎａｎｏｐａｒｔｉｃｌｅｓａｎｄｔｈｅｉｒａｐｐｌｉｃａｔｉｏｎｆｏｒｓｏｌｉｄ⁃ｐｈａｓｅｅｘｔｒａｃｔｉｏｎｏｆｐｏｌｙｃｙｃｌｉｃａｒｏｍａｔｉｃｈｙｄｒｏｃａｒｂｏｎｓｆｒｏｍｅｎｖｉｒｏｎｍｅｎｔａｌｗａｔｅｒｓａｍｐｌｅｓ［Ｊ］．ＪＣｈｒｏｍａｔｏｇｒＡ，２０１０，１２１７：４７５７⁃４７６４［１９］㊀ＺｈａｎｇＳＸ，ＮｉｕＨＹ，ＺｈａｎｇＹＹ，ｅｔａｌ．Ｂｉｏｃｏｍｐａｔｉｂｌｅｐｈｏｓｐｈａｔｉｄｙｌｃｈｏｌｉｎｅｂｉｌａｙｅｒｃｏａｔｅｄｏｎｍａｇｎｅｔｉｃｎａｎｏｐａｒｔｉｃｌｅｓａｎｄｔｈｅｉｒａｐｐｌｉｃａｔｉｏｎｉｎｔｈｅｅｘｔｒａｃｔｉｏｎｏｆｓｅｖｅｒａｌｐｏｌｙｃｙｃｌｉｃａｒｏｍａｔｉｃｈｙｄｒｏｃａｒｂｏｎｓｆｒｏｍｅｎｖｉｒｏｎｍｅｎｔａｌｗａｔｅｒａｎｄｍｉｌｋｓａｍｐｌｅｓ［Ｊ］．ＪＣｈｒｏｍａｔｏｇｒＡ，２０１２，１２３８：３８⁃４５［２０］㊀ＢｒｕｃｅＩＪ，ＳｅｎＴ，Ｓｕｒｆａｃｅｍｏｄｉｆｉｃａｔｉｏｎｏｆｍａｇｎｅｔｉｃｎａｎｏｐａｒｔｉｃｌｅｓｗｉｔｈａｌｋｏｘｙｓｉｌａｎｅｓａｎｄｔｈｅｉｒａｐｐｌｉｃａｔｉｏｎｉｎｍａｇｎｅｔｉｃｂｉｏｓｅｐａｒａｔｉｏｎｓ［Ｊ］．Ｌａｎｇｍｕｉｒ，２００５，２１：７０２９⁃７０３５［２１］㊀ＬｉＹ，ＬｅｎｇＴＨ，ＬｉｎＨＱ，ｅｔａｌ．ＰｒｅｐａｒａｔｉｏｎｏｆＦｅ３Ｏ４＠ＺｒＯ２ｃｏｒｅ⁃ｓｈｅｌｌｍｉｃｒｏｓｐｈｅｒｅｓａｓａｆｆｉｎｉｔｙｐｒｏｂｅｓｆｏｒｓｅｌｅｃｔｉｖｅｅｎｒｉｃｈｍｅｎｔａｎｄｄｉｒｅｃｔｄｅｔｅｒｍｉｎａｔｉｏｎｏｆｐｈｏｓｐｈｏｐｅｐｔｉｄｅｓｕｓｉｎｇｍａｔｒｉｘ⁃ａｓｓｉｓｔｅｄｌａｓｅｒｄｅｓｏｒｐｔｉｏｎｉｏｎｉｚａｔｉｏｎｍａｓｓｓｐｅｃｔｒｏｍｅｔｒｙ［Ｊ］．ＪＰｒｏｔｅｏｍｅＲｅｓ，２００７，６：４４９８⁃４５１０［２２］㊀ＬｉＹ，ＸｕＸＱ，ＱｉＤＷ，ｅｔａｌ．ＮｏｖｅｌＦｅ３Ｏ４＠ＴｉＯ２ｃｏｒｅ⁃ｓｈｅｌｌｍｉｃｒｏｓｐｈｅｒｅｓｆｏｒｓｅｌｅｃｔｉｖｅｅｎｒｉｃｈｍｅｎｔｏｆｐｈｏｓｐｈｏｐｅｐｔｉｄｅｓｉｎｐｈｏｓｐｈｏｐｒｏｔｅｏｍｅａｎａｌｙｓｉｓ［Ｊ］．ＪＰｒｏｔｅｏｍｅＲｅｓ，２００８，７：２５２６⁃２５３８［２３］㊀ＬｉｍＳＦ，ＺｈｅｎｇＹＭ，ＺｏｕＳＷ，ｅｔａｌ．ＣｈａｒａｃｔｅｒｉｚａｔｉｏｎｏｆｃｏｐｐｅｒａｄｓｏｒｐｔｉｏｎｏｎｔｏａｎａｌｇｉｎａｔｅｅｎｃａｐｓｕｌａｔｅｄｍａｇｎｅｔｉｃｓｏｒｂｅｎｔｂｙａｃｏｍｂｉｎｅｄＦＴ⁃ＩＲ，ＸＰＳ，ａｎｄｍａｔｈｅｍａｔｉｃａｌｍｏｄｅｌｉｎｇｓｔｕｄｙ［Ｊ］．ＥｎｖｉｒｏｎＳｃｉＴｅｃｈｎｏｌ，２００８，４２：２５５１⁃２５５６［２４］㊀ＰａｎＢ，ＸｉｎｇＢＳ．Ａｄｓｏｒｐｔｉｏｎｍｅｃｈａｎｉｓｍｓｏｆｏｒｇａｎｉｃｃｈｅｍｉｃａｌｓｏｎｃａｒｂｏｎｎａｎｏｔｕｂｅｓ［Ｊ］．ＥｎｖｉｒｏｎＳｃｉＴｅｃｈｎｏｌ，２００８．４２（２４）：９００５⁃９０１３［２５］㊀ＨｅｎｎｉｏｎＭＣ．Ｇｒａｐｈｉｔｉｚｅｄｃａｒｂｏｎｓｆｏｒｓｏｌｉｄ⁃ｐｈａｓｅｅｘｔｒａｃｔｉｏｎ［Ｊ］．ＪＣｈｒｏｍａｔｏｇｒＡ，２０００，８８５：７３⁃９５Ｃａｒｂｏｎｃｏａｔｅｄｍａｇｎｅｔｉｃｎａｎｏｐａｒｔｉｃｌｅｆｏｒｓｏｌｉｄ⁃ｐｈａｓｅｅｘｔｒａｃｔｉｏｎｏｆｐｈｔｈａｌａｔｅｅｓｔｅｒｓｆｒｏｍｗａｔｅｒｓａｍｐｌｅｓＷＡＮＧＹｉｎｇｈｕｉ１㊀㊀ＴＥＮＧＦｅｉ２㊀㊀ＺＨＡＮＧＹｕａｎｙｕａｎ３㊀㊀ＺＨＡＮＧＳｈｅｎｇｘｉａｏ３∗㊀㊀ＬＩＵＪｕｎｓｈｅｎ３㊀㊀ＷＵＱｉａｎ３（１．ＣｉｔｙＭａｎａｇｅｍｅｎｔＢｕｒｅａｕｏｆＥｎｖｉｒｏｎｍｅｎｔａｌＰｒｏｔｅｃｔｉｏｎｏｆＹａｎｔａｉＤｅｖｅｌｏｐｍｅｎｔＺｏｎｅ，Ｙａｎｔａｉ，２６４００６，Ｃｈｉｎａ；２．ＳｈａｎｇｈａｉＧｅｎｅｒａｌＭｏｔｏｒ（Ｄｏｎｇｙｕｅ）ＡｕｔｏＣｏｍｐａｎｙ，Ｙａｎｔａｉ，２６４００６，Ｃｈｉｎａ；㊀３．ＬｕｄｏｎｇＵｎｉｖｅｒｓｉｔｙ，Ｙａｎｔａｉ，２６４０２５，Ｃｈｉｎａ）ＡＢＳＴＲＡＣＴＣａｒｂｏｎｃｏａｔｅｄＦｅ３Ｏ４ｎａｎｏｐａｒｔｉｃｌｅｓ（Ｆｅ３Ｏ４／Ｃ）ｗｅｒｅｓｙｎｔｈｅｓｉｚｅｄｂｙａｓｉｍｐｌｅｈｙｄｒｏｔｈｅｒｍａｌｒｅａｃｔｉｏｎａｎｄａｐｐｌｉｅｄａｓｓｏｌｉｄ⁃ｐｈａｓｅｅｘｔｒａｃｔｉｏｎ（ＳＰＥ）ｓｏｒｂｅｎｔｓｔｏｅｘｔｒａｃｔｔｒａｃｅｐｈｔｈａｌａｔｅｅｓｔｅｒｓ（ＰＡＥｓ）ｆｒｏｍｅｎｖｉｒｏｎｍｅｎｔａｌｗａｔｅｒｓａｍｐｌｅｓ．ＴｈｅＦｅ３Ｏ４／Ｃｓｏｒｂｅｎｔｓｐｏｓｓｅｓｓｈｉｇｈｅｘｔｒａｃｔｉｏｎｅｆｆｉｃｉｅｎｃｙｄｕｅｔｏｓｔｒｏｎｇａｄｓｏｒｐｔｉｏｎａｂｉｌｉｔｙｏｆｃａｒｂｏｎｍａｔｅｒｉａｌｓａｎｄｌａｒｇｅｓｐｅｃｉｆｉｃｓｕｒｆａｃｅａｒｅａｏｆｔｈｅｎａｎｏｐａｒｔｉｃｌｅｓ．Ｏｎｌｙ５０ｍｇｏｆｓｏｒｂｅｎｔｓｗｅｒｅｎｅｅｄｅｄｔｏｅｘｔｒａｃｔＰＡＥｓｆｒｏｍ５００ｍＬｗａｔｅｒｓａｍｐｌｅｓ．Ｔｈｅａｄｓｏｒｐｔｉｏｎｒｅａｃｈｅｄｅｑｕｉｌｉｂｒｉｕｍｒａｐｉｄｌｙａｎｄｔｈｅａｎａｌｙｔｅｓｗｅｒｅｅｌｕｔｅｄｗｉｔｈａｃｅｔｏｎｉｔｒｉｌｅｒｅａｄｉｌｙ．ＳａｌｉｎｉｔｙａｎｄｓｏｌｕｔｉｏｎｐＨｈａｄｎｏｏｂｖｉｏｕｓｅｆｆｅｃｔｏｎｔｈｅｒｅｃｏｖｅｙｏｆＰＡＨｓ，ｗｈｉｃｈａｖｏｉｄｓｆｕｓｓｙａｄｊｕｓｔｍｅｎｔｔｏｗａｔｅｒｓａｍｐｌｅｂｅｆｏｒｅｅｘｔｒａｃｔｉｏｎ．Ｕｎｄｅｒｏｐｔｉｍｉｚｅｄｃｏｎｄｉｔｉｏｎｓ，ｔｈｅｄｅｔｅｃｔｉｏｎｌｉｍｉｔｏｆＰＡＥｓｗａｓｉｎｔｈｅｒａｎｇｅｏｆ１７５８ｎｇ㊃Ｌ－１．Ｔｈｅａｃｃｕｒａｃｙｏｆｔｈｅｍｅｔｈｏｄｗａｓｅｖａｌｕａｔｅｄｂｙｔｈｅｒｅｃｏｖｅｒｉｅｓｏｆｓｐｉｋｅｄｓａｍｐｌｅｓ．Ｇｏｏｄｒｅｃｏｖｅｒｉｅｓ（９４．６％１０６．６％）ｗｉｔｈｌｏｗｒｅｌａｔｉｖｅｓｔａｎｄａｒｄｄｅｖｉａｔｉｏｎｓｆｒｏｍ２％ｔｏ８％ｗｅｒｅａｃｈｉｅｖｅｄ．ＴｈｉｓｎｅｗＳＰＥｍｅｔｈｏｄｐｒｏｖｉｄｅｓｓｅｖｅｒａｌａｄｖａｎｔａｇｅｓ，ｓｕｃｈａｓｈｉｇｈｅｘｔｒａｃｔｉｏｎｅｆｆｉｃｉｅｎｃｙ，ｈｉｇｈｂｒｅａｋｔｈｒｏｕｇｈｖｏｌｕｍｅ，ｃｏｎｖｅｎｉｅｎｔｅｘｔｒａｃｔｉｏｎｐｒｏｃｅｄｕｒｅ，ａｎｄｓｈｏｒｔａｎａｌｙｓｉｓｔｉｍｅ．Ｋｅｙｗｏｒｄｓ：ＰＡＥｓ，ｍａｇｎｅｔｉｃｓｏｌｉｄ⁃ｐｈａｓｅｅｘｔｒａｃｔｉｏｎ，ｃａｒｂｏｎｍａｔｅｒｉａｌｓ．。

Essence cosmetics

Essence cosmeticsIn daily life, the girls always worries such as how to choose and buy cosmetics, learning the course, and finally can uncover cosmetics mysterious veil. Through chemical technology to cosmetics years study, I'm more profound understanding of the chemical applications in production.Essence of modulation technology, a classificationSweet: stimulates olfactory nerve (or taste nerve) a feeling of generalized called the smell, known as sweet. The smell of pleasure is called fragrance.The classification of aroma: due to the aroma type differ in thousands ways, sense organs discrepancy, the aroma classification method is multifarious.In 1865, for example, li man (Rimmel)According to various natural aroma, disease will aroma type induction of 18 types.The basic composition of flavor: as a seasoning of raw material spices, with road by classification, can be divided into:1 the Lord sweet agent: constitute the main body of the flavor aroma of the raw material base-sweet model2 and sweet agent: also called the coordination agent, its effect is will all kinds of spices mix together, can send the fragrance of life harmony.3 modifier: also called variable swap, its function is to use some spices aroma to modify another kind sweet material aroma, is in essence of can play features aroma effect.4 set incense agent: also called the sweet agent, and its function is to adjust the volatility for mixed composition, make the essence of stable lasting aroma.In addition, according to the composition of the safe for spices and stay sweet volatility for the time is different, also can be roughly divided into the sweet flavor will, body joss-stick and head sweet three parts. essence make up:1, The Formula of The Recommended:A. clear by scent of flavor and aroma chemicals, this as seasoning goal;B. according to the essence of the application requirements, choose quality level corresponding head sweet, body joss-stick joss-stick joss-stick and the material;C. with the main fragrant spices agent by the main part of the essence ?D. the xiang xiang gas accords with a requirement basically, he can add to make the conjunction of rich smell sweet agent, the modifier and attractive top sweet agent, make the fragrance lasting set incense agent;E. after repeatedly to match, the first try with 5 ~ 6 g flavor small kind, aroma quality evaluation;F. after authorization by the small kind evaluation, in the configuration 500 ~ 1000 g essenceDaY ang, add fragrant product in sitting in application2, the production processA. liquid essence production craft pure put day but sweet water soluble materials of static agent, dissolve the sweet pure oil from solution of soluble oil from pure into the solution agent products Points for a check for static filter ripe for sex with sweet dissolve put filling body fluidPoints for a check for filter ripe for filling liquid with put the bodyBuy a check of static filter ripe for inspection with fine into product water soluble irrigation with incense deodorant liquid into material in manufacturing process is typically spices should notice one of the link. The most common being taken on the way is to put the harmonic spices for a time in the tank, make its natural maturation. Age is a complex chemical reaction.B. powder essence production processa.crushing mix method is: if the incense are solid materials, the crushing mix method is to produce the most simple method powder flavor.b. the carrier absorption method: manufacturing powder for cosmetics powder essence, can use carrier absorption to preparation. Will the powder made (or liquid) essence and other carriers (such as CaCO3, MgCO3 powder) mixed, can be made into powder kind of cosmetics.c. essence assessment: the evaluation of the quality of incense, aroma of the evaluation of the strength and stay sweet time price evaluation. Cosmetics process many people, especially women in almost every day use cosmetic. The makeup of the good quality product already beautification life, and protect the skin health.Cosmetics kinds are very rich, classification approach also have varied.According to use purpose is divided into: basic cosmetics, beauty cosmetics, clean application cosmetics, other special use cosmetics.Cosmetics development process: cosmetics of popular products, renewal is faster.The product configuration form, products also need to pass a quality detection. After qualified, then the irrigation outfit, packaging, and finally form the goods into the market.Cosmetics formula design principle:1. Security design,2. Stability design,3 efficiency to design, 4. Compatibility sex,5.Sensory sex, practical and maneuverability,6.Economy.。

中捷石化公司开发出聚丙烯VOCs回收系统

第 6 期. 31 .from aqueous solution on chemically modified activated carbons［J］. Water Resour Res，2007，41（2）：333-340. [4] Zeledón-Toruño Z C，Lao-Luque C，de las Heras F X C，et al. Removal of PAHs from water using an immature coal （leonardite）［J］. Chemosphere，2007，67（3）：505-512. [5] 黄彪，刘文静，傅建炜，等. QuEChERS前处理法-超高效液相色谱串联质谱法同时测定茶油中7种烟碱类农药残留［J］. 农产品质量与安全，2019，12（1）：45-48；61.[6] 王玉娇，邓伟，刘通，等. 食品中香料香精分析方法研究进展［J］. 食品安全质量检测学报，2019，10（2）：400-406. [7] 白国涛，刘来俊，盛万里，等. QuEChERS-气相色谱-串联质谱法测定黄瓜中10种农药残留［J］. 农药学学报，2019，21（1）：89-96.[8] 张娟，汪杰，姚成虎. 分散固相萃取-气相色谱串联质谱法测定大米中的毒死蜱、三环唑和戊唑醇残留［J］. 农药，2018，57（11）：823-825；847.[9] Fromberg A，Højgård A，Duedahl-Olesen L. Analysis ofpolycyclic aromatic hydrocarbons in vegetable oils combining gel permeation chromatography with solid-phase extraction clean-up［J］. Food Addit Contam，2007，24（7）：758-767.[10] Wegrzyn E，Grzeskiewicz S，Poplawska W，et al. Modifiedanalytical method for polycyclic aromatic hydrocarbons，using sec for sample preparation and RP-HPLC with fluorescence detection. Application to different food samples［J］. Acta Bioconjugate Chem，2006，17（8）：233-249.[11] 柳菡，龚玉霞，王绳芸，等. 气相色谱-串联质谱法测定蛋和蛋制品中氟虫腈及其代谢物残留量［J］. 质谱学报，2019，40（1）：74-82.[12] 卜晓娜，刘楚君，郭亚文，等. 动物源性食品中四环素类药物残留的色谱和质谱检测技术的研究进展［J］. 中国兽医科学，2018，48（11）：1464-1474.[13] Knopp D，Seifert M，Väänänen V，et al. Determination ofpolycyclic aromatic hydrocarbons in contaminated water and soil samples by immunological and chromatographic methods ［J］. Environ Sci Technol，2000，34（10）：2035-2041. [14] Pandey M K，Mishra K K，Khanna S K，et al. Detection ofpolycyclic aromatic hydrocarbons in commonly consumed edible oils and their likely intake in the Indian population［J］.J Am Oil Chem，2004，81（12）：1131-1136.[15] 周秋玲，娄婷婷，王素英，等. 动物源性食品中性激素检测方法的比较分析［J］. 食品研究与开发，2018，39（9）：183-189.[16] 谢瑜杰，陈辉，彭涛，等. 食品与饲料基质中真菌毒素检测技术研究进展［J］. 食品安全质量检测学报，2018，9（6）：1234-1246.[17] 张宏康，王中瑗，杨启津，等. 同位素稀释质谱法在食品分析中的应用研究进展［J］. 食品科学，2018，39（23）：280-288.[18] 刘永明，葛娜，崔宗岩，等. 粮谷中农药残留前处理技术的研究进展［J］. 食品安全质量检测学报，2014，5（7）：2151-2160.[19] Emmenegger C，Kalberer M，Morrical B，et al. Quantitativeanalysis of polycyclic aromatic hydrocarbons in water in the low-nanogram per liter range with two-step laser mass spectrometry［J］. Anal Chem，2003，75（17）：4508-4513. [20] 李小佳，马康，弓爱君，等. 酒类产品中食品添加剂的检测技术进展［J］. 食品安全质量检测学报，2014，5（5）：1451-1458.[21] 张亚莉，哈婧，赵静，等. 动物组织中抗生素残留研究进展［J］. 河北科技大学学报，2013，34（6）：517-525.刘发强等. 气相色谱-串联质谱在检测塑料包装食用油中PAHs的应用中海石油中捷石化有限公司（简称中捷石化公司）开发出一种聚丙烯挥发性有机物（VOCs）环保回收系统，包括闪蒸置换尾气回收系统和加料斗活化剂氮气压送系统。

基于多糖调节肌原纤维蛋白凝胶特性的研究进展

吕旭琴，周娇娇，蔡杰，等. 基于多糖调节肌原纤维蛋白凝胶特性的研究进展[J]. 食品工业科技，2022，43（19）：446−452. doi:10.13386/j.issn1002-0306.2021100012LÜ Xuqin, ZHOU Jiaojiao, CAI Jie, et al. Research Progress in Regulation of the Gel Properties of Myofibrillar Protein Based on Polysaccharides[J]. Science and Technology of Food Industry, 2022, 43(19): 446−452. (in Chinese with English abstract). doi:10.13386/j.issn1002-0306.2021100012· 专题综述 ·基于多糖调节肌原纤维蛋白凝胶特性的研究进展吕旭琴1,2，周娇娇1,2, *，蔡　杰1,2, *，贾继来1，陈　磊2，程水源1（1.武汉轻工大学硒科学与工程现代产业学院/国家富硒农产品加工技术研发专业中心，湖北武汉 430023；2.武汉轻工大学食品科学与工程学院，湖北武汉 430023）摘　要：肌原纤维蛋白（myofibrillar protein ，MP ）作为肌肉中具有重要生物学功能的结构蛋白，能单独形成凝胶或作为凝胶的主要部分。

MP 的凝胶作用机理及凝胶特性已成为肉类科学研究的热点。

明确各种添加剂对肉制品品质的影响，为开发健康的低脂肉制品提供依据。

多糖具有良好的生物相容性且来源广泛、价格低廉，被广泛用于改善肉制品的品质。

然而，目前多糖调节MP 凝胶特性的研究并没有得到较为全面的归纳与总结。

故本文概括了多糖的定义、分类以及功能特性，总结了多糖对MP 凝胶特性的影响以及多糖在肉制品中的应用，以期为低脂肉制品的生产提供理论依据，并提出未来的研究方向。

The Chemistry of Crystallography

The Chemistry of Crystallography IntroductionCrystallography is a branch of science that studies crystals and their properties. It involves the use of X-ray diffraction to determine the atomic structure of crystals. This approach has been used extensively in the field of chemistry to study the properties of materials and their behavior at the atomic level. In this article, we will explore the chemistry of crystallography.The Importance of Crystallography in ChemistryThe study of crystallography is important in chemistry for a number of reasons. First, it allows us to determine the structure of materials at the atomic level. This information is critical for understanding the properties of materials and how they interact with other substances.For example, the crystallographic structure of a protein can provide valuable insights into its function. By determining the structure of a protein, we can understand how it interacts with other molecules in the body and design drugs that target specific binding sites.Crystallography is also important in the study of materials science. By understanding the crystal structure of a material, we can predict its physical and chemical properties. This information can be used to develop new materials with specific properties such as strength, conductivity, and catalytic activity.How Crystallography WorksCrystallography works by using X-rays to determine the positions of atoms in a crystal. When X-rays are passed through a crystal, they diffract, or bend, as they interact with the atoms in the crystal lattice. The diffracted X-rays form a pattern that can be used to determine the position of the atoms in the crystal.To obtain a crystal suitable for X-ray diffraction, the substance must first be crystallized. This is achieved by dissolving the substance in a solvent and allowing the solvent to evaporate slowly. This process leads to the formation of a crystal, which can be analyzed using X-ray diffraction.The process of X-ray diffraction involves projecting a beam of X-rays onto the crystal and measuring the angles at which the diffracted X-rays impinge on a detector. From these measurements, the relative positions of the atoms in the crystal can be calculated.Applications of Crystallography in ChemistryCrystallography has a wide range of applications in the field of chemistry. One of the most important applications is in the study of small molecules. By determining the structure of a small molecule, chemists can understand how it interacts with other molecules and identify potential uses for the molecule.Crystallography is also used in the study of larger molecules such as proteins, nucleic acids, and carbohydrates. The structure of these complex molecules can provide valuable insights into their function and interactions with other molecules in the body.Crystallography is also used in the study of materials science. By understanding the crystal structure of a material, scientists can predict its physical and chemical properties and design new materials with specific properties.ConclusionIn conclusion, the chemistry of crystallography plays an important role in our understanding of materials and their properties. By using X-ray diffraction to determine the atomic structure of crystals, scientists can gain insights into the properties of materials and their behavior at the atomic level. Crystallography has a wide range of applications in the field of chemistry, from the study of small molecules to the development of new materials. It is a powerful tool that has revolutionized our understanding of the world around us.。

Study on the Properties of Liquid Crystal Polymers

Study on the Properties of LiquidCrystal PolymersLiquid crystal polymers (LCPs) have garnered a lot of attention lately due to their unique properties. These materials are made up of long, chain-like molecules that have both liquid and crystalline properties. They are known for their high strength, stiffness, and heat resistance, as well as their ability to self-organize into complex structures. In this article, we will delve deeper into the properties of LCPs and explore some potential applications of these fascinating materials.Structure of Liquid Crystal PolymersLCPs are made up of long, chain-like molecules called polymers. The chains are composed of repeating units called monomers, which are often derived from aromatic compounds. These molecules are characterized by their rigid, rod-like shapes, which give them their unique properties.The molecules in LCPs are arranged in such a way that they exhibit both liquid-like and crystalline properties. The molecules can flow and move around like a liquid, but they also have a degree of order and alignment, similar to a crystal. This alignment is due to the intermolecular forces between the chains, which orient the molecules in a particular direction.The degree of alignment in LCPs can be controlled by factors such as temperature, pressure, and the presence of other molecules. For example, at high temperatures, the chains are more disordered and liquid-like, while at low temperatures, the chains become more ordered and crystalline. This ability to control the structure of LCPs makes them attractive for a variety of applications.Properties of Liquid Crystal PolymersLCPs possess a number of unique properties that make them useful in a variety of applications. Some of these properties include:1. High Strength: LCPs are known for their high strength and stiffness, making them useful in applications where durability is important.2. Heat Resistance: LCPs have high melting points and can withstand high temperatures without degrading. This property makes them useful in applications where high temperatures are involved.3. Chemical Resistance: LCPs are resistant to many chemicals, including acids, bases, and solvents. This makes them useful in applications where exposure to harsh chemicals is common.4. Self-Organizing: LCPs have the ability to self-organize into complex structures, due to the alignment of the molecules. This property makes them useful in applications where precise structures are necessary.Applications of Liquid Crystal PolymersLCPs have a wide range of potential applications, due to their unique properties. Some of the most promising applications include:1. Aerospace: Due to their high strength, stiffness, and heat resistance, LCPs are being studied for use in aerospace applications, such as lightweight structural components for aircraft and spacecraft.2. Electronics: LCPs are being explored for use in electronics applications, such as flexible displays and sensors. Their self-organizing properties make them attractive for creating precise, ordered structures at the nanoscale.3. Medical Devices: LCPs are being investigated for use in medical devices, such as implantable sensors and drug delivery systems. Their chemical resistance and biocompatibility make them useful for applications where exposure to harsh chemicals or biological fluids is common.4. Packaging: LCPs are being studied for use in food packaging, due to their abilityto withstand high temperatures and resistance to chemicals. They could help reduce food waste by extending the shelf life of perishable goods.ConclusionLiquid crystal polymers are a class of materials that have unique properties due to their liquid-crystalline structure. These properties, such as high strength, stiffness, and heat resistance, make them attractive for a variety of applications. As research into LCPs continues, it is likely that new applications will be discovered, making these materials even more valuable in the future.。

关于花的实验的英文作文题目

关于花的实验的英文作文题目回答例子1:Title: "Exploring Floral Beauty: An Experiment on the Fascinating World of Flowers"Introduction:Flowers, with their captivating colors, intricate patterns, and alluring fragrances, have intrigued humanity for centuries. Beyond their aesthetic appeal, flowers play crucial roles in ecosystems, from attracting pollinators to providing food and shelter for various organisms. In this experiment, we delve into the realm of flowers to unravel their mysteries, explore their diverse characteristics, and understand their significance in nature.Experiment Objective:The primary aim of this experiment is to investigate the physiological and ecological aspects of different types of flowers. By conducting various tests and observations, we seek to comprehend the factors influencing flower growth, development, and interactions with the environment.Experimental Design:1. Selection of Flower Species: Choose a diverse range of flower species, including both native and exotic varieties, to study their unique traits and adaptations.2. Growth Conditions: Cultivate the selected flowers in controlled environments with varying factors such as light intensity, temperature, soil composition, and water availability.3. Data Collection: Record observations on flower growth rates, blooming patterns, color variations, and responses to environmental stimuli over specific time intervals.4. Pollination Studies: Investigate the mechanisms of pollination by observing interactions between flowers and pollinators such as bees, butterflies, and birds.5. Ecological Impact: Analyze the ecological roles of flowers in supporting biodiversity, enhancing ecosystem stability, and providing ecosystem services such as pollination and habitat provision.Experimental Procedures:1. Germination: Start the experiment by germinating flower seeds or propagating young plants from cuttings.2. Growth Monitoring: Regularly measure plant height, leaf development, and bud formation to track growth progress.3. Flowering Stage: Document the stages of flower development from bud formation to full bloom, noting any abnormalities or deviations from typical growth patterns.4. Environmental Manipulation: Alter environmental conditions (e.g., light exposure, temperature regimes) to assess their impact on flower growth and development.5. Pollination Observations: Observe pollinator visits to flowers, noting the frequency and effectiveness of pollination events.6. Data Analysis: Compile and analyze the collected data to identify patterns, correlations, and potential causal relationships between environmental factors and flower characteristics.Results and Discussion:The experiment yielded valuable insights into the intricate dynamics of flower biology and ecology. Through careful observation and analysis, we discovered the following key findings:1. Influence of Environmental Factors: Light intensity,temperature, and soil nutrients significantly influence flower growth and blooming patterns.2. Pollination Efficiency: Different flower species exhibit varying degrees of attractiveness to pollinators, affecting pollination rates and reproductive success.3. Ecological Significance: Flowers play essential roles in supporting pollinator populations, maintaining ecosystem health, and sustaining biodiversity.4. Adaptations to Environmental Stress: Some flowers demonstrate remarkable resilience to environmental stressors, showcasing adaptive traits such as drought tolerance or shade tolerance.5. Human Impacts: Human activities such as habitat destruction, pollution, and climate change pose threats to floral diversity and ecosystem functioning, highlighting the need for conservation efforts.Conclusion:In conclusion, our experiment sheds light on the fascinating world of flowers and their ecological significance. By unraveling the intricate relationships between flowers and their environment, we gain a deeper appreciation for thebeauty and importance of these botanical wonders. Moving forward, further research and conservation efforts are essential to preserve floral diversity and safeguard ecosystem health for future generations.回答例子2:Title: "Exploring the Mysteries of Flowers: An Experimental Journey"Introduction:Flowers, with their captivating beauty and intricate structures, have fascinated humanity for centuries. Beyond their aesthetic appeal, flowers play essential roles in ecosystems and human culture. In this essay, we embark on an experimental exploration of flowers, delving into their biology, behavior, and significance through various experiments.Experiment 1: Floral Anatomy and MorphologyOur first experiment involves dissecting different types of flowers to explore their anatomy and morphology. By carefully examining the petals, sepals, stamens, and pistils, we gain insights into the reproductive structures and mechanisms of flowers. Through microscopy, we observe the intricatepatterns and textures that make each flower unique. This experiment deepens our understanding of the diversity and complexity of floral structures across plant species.Experiment 2: Pollination DynamicsPollination is a critical process for the reproduction of flowering plants, and our second experiment focuses on understanding its dynamics. Using controlled environments, we observe how different pollinators, such as bees, butterflies, and birds, interact with flowers. Through pollen analysis and observation of pollinator behavior, we investigate the efficiency and effectiveness of various pollination strategies. This experiment sheds light on the co-evolutionary relationships between plants and their pollinators, highlighting the importance of biodiversity in maintaining healthy ecosystems.Experiment 3: Floral Fragrance and AttractionFlowers often emit fragrances to attract pollinators and repel herbivores, and our third experiment explores the chemical composition and biological significance of floral scents. Using gas chromatography-mass spectrometry(GC-MS), we identify the volatile compounds responsible for specific floral fragrances. Through behavioral assays with pollinators and herbivores, we examine the role of floral scents in mediating plant-insect interactions. This experiment elucidates the multifaceted functions of floral fragrances in plant reproduction and defense strategies.Experiment 4: Flower Coloration and UV PatternsThe vibrant colors of flowers play a crucial role in attracting pollinators and signaling ripeness, and our fourth experiment investigates the mechanisms behind flower coloration. Using spectrophotometry and UV photography, we analyze the pigments and UV patterns present in different flower species. By manipulating light conditions and observing pollinator preferences, we discern the adaptive significance of flower coloration in ecological contexts. This experiment unravels the intricate interplay between genetics, environment, and evolution in shaping floral traits.Conclusion:Through a series of experiments, we have unveiled some of the mysteries surrounding flowers, from their intricateanatomy to their ecological functions. Our journey has underscored the remarkable diversity and complexity of the floral world, highlighting the interconnectedness between plants, pollinators, and their environments. As we continue to explore the wonders of flowers, let us cherish and protect these precious symbols of beauty and life on our planet.。

南充2024年统编版小学四年级下册第9次英语第1单元真题

南充2024年统编版小学四年级下册英语第1单元真题(含答案)考试时间：90分钟（总分:140）B卷一、综合题(共计100题)1、What is 15 divided by 3?A. 4B. 5C. 6D. 7答案: B2、填空题：I have a lovely ________ (洋娃娃) that wears a pink dress. I like to take her to the________ (公园).3、听力题：A solute is a substance that is ______ in a solution.4、选择题：What do you call a small house for a dog?A. KennelB. CageC. BarnD. Shed5、填空题：I want to learn how to ________ (骑车).6、选择题：What is the main ingredient in chocolate cake?A. SugarB. CocoaC. FlourD. Eggs7、听力题：She is ___ (reading/writing) a letter.8、听力题：The process of electrolysis uses electricity to cause a _____ reaction.9、Which instrument is played by blowing air into it?A. PianoB. GuitarC. FluteD. Drum答案:C10、填空题：A hedgehog can curl into a _______ (球) when scared.11、听力题：The pH scale ranges from to _______.12、听力题：The ______ is known for its elaborate courtship dance.13、听力题：The chemical symbol for aluminium is ________.14、Which direction does the sun rise?a. Northb. Southc. Eastd. West答案:c15、填空题：The _______ (The Civil Rights Act) aimed to end segregation in public places.16、听力题：The chemical symbol for argon is ______.17、填空题：A ______ (植物的利用) can lead to innovative products.18、What do we call the part of the Earth that supports life?A. BiosphereB. AtmosphereC. LithosphereD. Hydrosphere答案:A19、听力题：A seahorse is a unique type of ______.20、How many months have 28 days?A. 1B. 2C. 12D. 1021、听力题：An electric circuit needs a ______ to flow.22、填空题：The rabbit loves to hop around the ______.23、填空题：The ________ was a famous ship that sank in 1912.24、填空题：The _____ (小猫) plays with a ball of yarn. It is so playful! 小猫在玩一团毛线。

小果蔷薇不同采收时期叶和茎中主要活性成分的变化

周瑶瑶，张晓元，陈雄，等. 小果蔷薇不同采收时期叶和茎中主要活性成分的变化[J]. 食品工业科技，2024，45（2）：220−226. doi:10.13386/j.issn1002-0306.2023020208ZHOU Yaoyao, ZHANG Xiaoyuan, CHEN Xiong, et al. Changes of Main Active Components in Leaf and Stem of Rosa cymosa Tratt.at Different Harvesting Periods[J]. Science and Technology of Food Industry, 2024, 45(2): 220−226. (in Chinese with English abstract).doi: 10.13386/j.issn1002-0306.2023020208· 分析检测 ·小果蔷薇不同采收时期叶和茎中主要活性成分的变化周瑶瑶1,2，张晓元2,3, +, *，陈　雄2，罗韶刚2，曾令杰1, *（1.广东药科大学中药学院，广东广州 510006；2.韶关市华工高新技术产业研究院，广东韶关 512027；3.华南理工大学工业技术研究总院，广东广州 510640）摘　要：目的：探索一年中不同采收时期小果蔷薇叶和茎中总多糖、总有机酸、鞣花酸的含量变化情况，为其质量控制和适宜采收期的确定提供实验依据。

方法：于2021年的2月至12月采集小果蔷薇的茎和叶的样品，每月采集1次。

样品阴干后，分别采用紫外分光光度法测定其总多糖和总有机酸和含量，用高效液相色谱法测定其鞣花酸含量。

同时采用聚类分析和主成分分析对不同采收时期的叶和茎进行综合评价。

结果：叶和茎中总多糖、总有机酸、鞣花酸的含量在一年中呈现一定的波动趋势。

叶中总多糖含量在7月（22.689 mg·g −1）和8月（23.164 mg·g −1）达到较高水平；总有机酸在2月（111.484 mg·g −1）、6月（113.342 mg·g −1）、8月（102.425 mg·g −1）含量最高；鞣花酸在4月（0.074 mg·g −1）、6月（0.077 mg·g −1）和8月（0.074 mg·g −1）含量最高。

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Journal of Hazardous Materials 183 (2010) 70–80Contents lists available at ScienceDirectJournal of HazardousMaterialsj 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 /j h a z m atA seasonal study of polycyclic aromatic hydrocarbons in PM 2.5and PM 2.5–10in ﬁve typical cities of Liaoning Province,ChinaShaofei Kong,Xiao Ding,Zhipeng Bai ∗,Bin Han,Li Chen,Jianwu Shi,Zhiyong LiState Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control,College of Environmental Science and Engineering,Nankai University,Weijin Road 94#,Tianjin 300071,Chinaa r t i c l e i n f o Article history:Received 24December 2009Received in revised form 12June 2010Accepted 28June 2010Available online 31 July 2010Keywords:Particulate matterPolycyclic aromatic hydrocarbons Diagnostic ratioPrincipal component analysisa b s t r a c tFourteen polycyclic aromatic hydrocarbons (PAHs)in PM 2.5and PM 2.5–10samples collected in ﬁve cities (Shenyang,Anshan,Jinzhou,Fushun and Dalian),Liaoning Province,China in 2004and 2005were analyzed by using a HPLC equipped with ﬂuorescence and UV detectors.Results showed total PAHs con-centrations in PM 2.5and PM 2.5–10were in the range of 75.32–1900.89ng m −3and 16.74–303.24ng m −3,respectively.90%of the total PAHs were in PM 2.5.PAHs in PM 2.5had a winter to summer ratio varying from 6.5to 125.8while PAHs in PM 2.5–10had a ratio ranging from 1.7to 37.6.Total PAHs concentra-tions were most abundant at residential/commercial sites and were fewest at an industrial site for both PM 2.5and PM 2.5–10.Urban background sites showed unexpected higher PAHs concentrations.Total BaP equivalent concentration (BaPeq)for PM 2.5ranged from 7.80to 88.42ng m −3in different function zones.Similarities of PAHs proﬁles between sampling sites and between ﬁne and coarse fractions were com-pared by coefﬁcient of divergence which indicated that remarkable differences in PAHs compositions existed.Principal component analysis (PCA)associated with diagnostic ratios revealed coal combustion and vehicle emission were the major sources for PM 2.5and PM 2.5–10associated PAHs.© 2010 Elsevier B.V. All rights reserved.1.IntroductionPolycyclic aromatic hydrocarbons (PAHs)have been widely accepted as a class of ubiquitous and mutagenic environmental pollutants and attracted much attention in previous studies on air pollution recently [1,2].PAHs are products of incomplete combus-tion and pyrolysis of fossil fuels such as petroleum and coal and other organic materials from natural and anthropogenic sources [3–13]including fossil fuels combustion [14],vehicle exhaust [15,16],open-ﬁre straw burning [16,17],cigarette smoking [17],wood combustion [18],industrial production [19],including waste incineration [6],metal production [20],coke production [20],iron production [5,17],airplane production [17],etc.Results of previ-ous studies had shown that the main sources of PAHs in urban area were trafﬁc exhaust (diesel or gasoline)and certain industrial pro-cesses [20,21].Zhang and Tao [17]pointed out that in China,the major emission sources for atmospheric PAHs were biofuel,coke production,domestic coal,trafﬁc oil,open straw burning,petrol reﬁnery and consumer products which contributed 66.4%,14.4%,10.7%,2.0%,2.0%,1.0%and 0.9%,respectively.Tian et al.[22]con-cluded that in heating period,the main pollution sources were∗Corresponding author.Tel.:+862223503397.E-mail addresses:zbai@ ,hanbin@ (Z.Bai).coal-ﬁred boiler emission (56%),residential coal combustion (33%)and trafﬁc emissions (11%).As for non-heating period,the main sources were gasoline engine emission,trafﬁc tunnel emission and coal-ﬁred power plant,and the overall source contributions of traf-ﬁc emission (gasoline engine in trafﬁc tunnel)was 79%and of coal-ﬁred power plant was 21%in Dalian,China.An important property-particle size determined the PAHs size distribution,and furthermore,the inhalable and respirable PAHs fractions [3].In general,average ﬁne particulate PAHs concentra-tions were all higher than coarse particulate PAHs concentrations [23–25].Schnelle-Kreis et al.[26]found that in most cases the amount of PAHs associated with coarse particles was less than 10%of the total.Baek et al.[27]reported that 95%of particulate PAHs sampled in London were in particles with diameter less than 3.3␮m.Temporal variation of PAHs has been investigated in some stud-ies and most results showed higher PAHs concentrations in winter than in summer [4,20,21,24,28,29].Although several studies have been conducted to compare PAHs between urban sites and subur-ban sites [4,24,25,30],only a few measurements were conducted to compare the difference in different function zones in urban areas [31–32].In particular,benzo[a]pyrene (BaP)had always been selected as an indicator of carcinogenic PAHs [24,32]and some countries and organizations had also set up standards for it.The guided level of0304-3894/$–see front matter © 2010 Elsevier B.V. All rights reserved.doi:10.1016/j.jhazmat.2010.06.107S.Kong et al./Journal of Hazardous Materials 183 (2010) 70–8071BaP is 0.25ng m −3in USA [8],1.0ng m −3in European Union [8,21],0.25ng m −3in UK [21,24],1.0ng m −3in Italy [24],1.0ng m −3in WHO [33]and 10ng m −3in China [34].While the environmen-tal health risk associated with exposure to atmospheric particulate PAHs has yet not to be assessed for the cities of Liaoning Province.PAHs are present in both aerosol phases.The PAHs of low molec-ular weight (2and 3aromatic rings)were found preferentially in the gas phase while the ones of larger molecular weight (4–6aromatic rings)were found adsorbed on the surface of suspended particles [2,3,11,19,20,29,32].Therefore,it is important to evaluate the amount,distribution and possible sources of PAHs in the atmo-spheric aerosols since their absorbed amount through breathing depends upon their atmospheric concentration [35].In Liaoning Province,air quality monitoring networks have been constructed to monitor criteria air pollutants such as SO 2,NO x ,CO,O 3and PM 10.Less attention has been paid on monitoring PAHs that requires more elaborate sampling and analytical protocols.Stud-ies related to PAHs have recently been conducted in some cities such as Shenyang [36]and Dalian [22].The main objectives of these studies were to detect and quantify the PAHs compounds in PM.However,PAHs partition between PM 2.5(particles with aero-dynamic diameter less than 2.5␮m,ﬁne fraction)and PM 2.5–10(2.5␮m <aerodynamic diameter <10␮m,coarse fraction)is still unknown.It is important to conduct detailed and systematic PAHs proﬁles for particulate matter for the purpose of effective air pol-lution control and establishing air quality standards by assessing public exposure to PAHs and their associated health risks [23].We have performed a four-season PM 2.5and PM 2.5–10sampling in 2004and 2005at 10sites in ﬁve cities which covered different city zones of Liaoning Province.We focused on characteristic,tem-poral and spatial distribution as well as sources for both ﬁne and coarse particulate PAHs.The main objectives of this study were to:(1)give the PAHs levels of PM in Liaoning Province;(2)identify the seasonal variation of PAHs concentration and distribution pattern associated with ﬁne and coarse fraction;(3)compare the status of PAHs pollution in different city function zones;(4)identify their possible sources.It is expected that the results from this study will provide a baseline reference for a global database as well as for regulatory action to improve air quality in these cities.2.Experimental2.1.Sampling area and sites descriptionLiaoning province is located in the eastern shore of Eurasia,under the control of a continental monsoonal climate within a warm temperate zone.The terrain of the province is complex,including mountain,plain,hill and coast.Annual average tem-perature is between 5and 10◦C,decreasing from coastal area to inland.The average yearly rainfall is between 500and 1000mm,decreasing from east to west.The precipitation is mainly in sum-mer,accounting for 60–75%.Long cold period,strong wind in the plain area,wet in the east and dry in the west,concentrative precip-itation in summer,plenitudinous sunlight and distinct four seasons are the main climate characteristics of the province.As the tradi-tionary heavy-industrial base of China,the major industry system of the province includes metallurgy,mechanics,petrochemical,con-struction material and so on.Considering differences in topography,meteorology,industrial structure and air quality,ﬁve representative cities includ-ing Shenyang (122◦25 –123◦48 E,41◦11 –43◦02 N),Anshan (122◦10 –123◦13 E,40◦27 –41◦34 N),Fushun (123◦39 –125◦28 E,41◦41 –42◦38 N),Jinzhou (120◦42 –122◦37 E,40◦48 –42◦08 N)and Dalian (120◦58 –123◦31 E,38◦43 –40◦10 N)were selected to study the characterization of PM-bound PAHs in Liaoning Province.Locations of these ﬁve cities are indicated in Fig.1.T a b l e 1G e o m e t r i c m e a n c o n c e n t r a t i o n s o f P A H s i n P M 2.5a n d P M 2.5–10a t 10s i t e s i n ﬁv e s e l e c t e d c i t i e s d u r i n g s a m p l i n g p e r i o d s (n g m −3).P A H sP M 2.5P M 2.5-10S h e n y a n gA n s h a n F u s h u n J i n z h o uD a l i a nS h e n y a n g A n s h a nF u s h u n J i n z h o u D a l i a n S Z (n =53)T Y J (n =51)SG S (n =51)A S J (n =51)T X Z (n =45)S K (n =53)Z Q (n =53)N S (n =51)J Z J (n =50)G J Z (n =50)S Z (n =53)T Y J (n =51)S G S (n =51)A S J (n =51)T X Z (n =45)S K (n =53)Z Q (n =53)N S (n =51)J Z J (n =50)G J Z (n =50)N a p 3.494.810.981.011.000.731.530.650.921.523.573.090.390.230.182.626.330.550.741.04A c e 4.053.56103.41133.90212.721.792.332.530.411.141.521.544.737.4122.613.452.940.351.660.85P h e 69.9892.6815.1914.4029.8421.0874.1810.735.587.0948.465.033.064.416.5015.4128.42.572.494.43A n t 1.7664.074.235.6010.248.3910.773.501.730.980.511.090.680.711.722.743.410.740.560.62F l u 20.39311.7748.6467.94116.6070.45560.3842.5329.6912.515.1614.276.615.3215.8717.7147.434.984.304.38P y r 15.23272.8151.0762.28108.9952.26583.6730.6914.138.102.1710.405.397.2215.3313.4345.562.871.552.40B a A 5.9064.0521.1226.5050.4817.71190.2320.7310.376.060.772.862.652.746.513.4311.451.871.101.28C h r 8.1381.0422.3326.7149.8523.09203.7813.645.817.631.683.692.382.826.214.8512.811.490.611.66B b F 14.2165.6725.4729.7956.6923.96115.1719.5310.818.922.164.442.613.026.413.625.701.660.961.92B k F 3.5516.3719.7722.2244.176.0933.616.173.602.880.711.062.712.955.361.381.830.560.240.77B a P 5.9331.7120.1524.0947.3810.7148.4413.616.615.391.132.042.502.956.011.983.441.130.770.91D b A 9.1423.6442.4752.48105.0712.8941.8213.8410.456.652.561.833.284.3410.551.922.031.231.071.29B g h i P 1.404.7623.9429.9260.084.428.622.611.591.630.700.721.872.416.281.060.380.420.130.35I n d 7.3516.8912.4315.2429.908.9826.3710.756.164.831.181.661.071.413.201.461.540.910.561.22 P A H s170.501053.83411.21512.08923.01262.531900.89191.49107.8775.3272.2753.7339.9247.96112.7275.07173.2421.3516.7423.1272S.Kong et al./Journal of Hazardous Materials183 (2010) 70–80Fig.1.Location of theﬁve selected cities and the sampling sites.Shenyang,as the capital city of Liaoning Province and the biggest city in the Northeast area of China,lies in the middle plain of the province.The main industry is mechanics.Locating at the west of Qianshan Mountain,Anshan is one of the most important iron and steel base in China.Fushun,a famous city owing to coal,is situated in the eastern mountainous area of the province with petrochemi-cal and coal as its supporting industry.Jinzhou,which is the trafﬁc ligament connecting Northeast District of China and other districts lies on the north of Bohai Sea,with metallurgy and petrochemi-cal as its dominant industry.Dalian,a coastal city,lies in the south of Liaodong peninsula and the principal industries are shipbuild-ing,petrochemical and mechanics.According to the bulletins of environmental situation published by Liaoning Environmental Pro-tection Bureau from2000to2004,the primary air pollutant was PM10.Except for Dalian,PM10in the other four cities all exceeded the national annual secondary standards(0.1mg m−3for PM10) [37].Two sampling sites were selected for each city,except for Anshan and Dalian.All these sites are national routine monitor-ing stations.There were two sites in Shenyang:SZ(a residential area)and TYJ(a commercial area,near major roads with high traf-ﬁc volume,lots of construction activities and barbecue sites);three sites in Anshan:SGS(a residential area),ASJ(a residential area)and TXZ(an industrial/commercial area,near Anshan steel smelt cor-poration,17coal combustion boilers within1km,annual total coal consumption was16,000tons);two sites in Fushun:SK(an urban background site,10km away from two power plant,about20coal combustion boilers within1km)and ZQ(a residential/commercial area,2km away from Fushun power plant,heavy trafﬁc,tens of boilers for hotel and bathhouse);two sites in Jinzhou:NS(an urban background site,12coal combustion boilers within1km,annual total coal consumption was16,000tons,an iron smelt stove about 1km on the windward direction,an mixing site for bitumen within 0.9km on the southeast)and JZJ(a residential area,32pollution sources including16coal combustion boilers within1km,annual total coal consumption was70,000tons);one site in Dalian:GJZ (an industrial area,special industry area,60%of industry sources of Dalian concentrated here).There are total four residential sites, one residential and commercial mixed site,one commercial site, one commercial and industrial mixed site,one industrial site and two urban background sites,differing substantially in industry structure and were also expected to vary signiﬁcantly in particu-late associated PAHs.Sampling equipments were all placed on the rooftop of each site of the air quality monitoring network set by local government,3–15m above ground level.2.2.SamplingMeasurements were carried out inﬁve cities simultaneously between2004and2005.Samplings were carried out during the ﬁrst halves of January,April,July and October to represent four seasons.Each sampling began at8:30a.m.and continued for24h. These samples were collected on consecutive days in all four sea-sons except extreme meteorological conditions such as rain,snow or strong wind(wind speed higher than8m s−1).Ambient air par-ticulate matter was continuously collected onto quartzﬁlters(Ø37mm,Pall Gelman Laboratory,Ann Arbor,MI)using dichotomous samplers(Model TH-15S,Wuhan Tianhong Instument Factory) with a10␮m cut point before inlet at a rate of15.03L/min forﬁne particulate matter and1.67L/min for coarse fraction for24h.The ﬂow rate of each dichotomous sampler,equipped with a massﬂow controller,was calibrated automatically with bubbleﬂow meters to ensure a constantﬂow rate.Flow rate variations throughout each 24h sampling were within±5%.Prior to sampling,quartzﬁberﬁlters were calcined at400◦C for 4h to remove any organic compounds that may be present on the ﬁlters.Filters were weighted by a sensitive microbalance(Meter Toledo MX5)with balance sensitivity±1␮g.Prior to weighing,the ﬁlters were equilibrated in a desiccator at room temperature within 48h and then weighed before and after sample collection.After sampling,theﬁlters were removed from the inlet,folded in half and wrapped in a laminar-ﬂow clean hood until use.Filter blanks were assessed in the same procedure.After weighing,theﬁlters were stored at−20◦C until analysis.2.3.Analytical procedureHalf of eachﬁlter was cut into pieces to5mL centrifugal glass tube with5mL acetonitrile.PAHs were removed from theﬁlter using ultrasonic extraction for10min and then reconcentrated for 10min using a centrifuge with600r/min.10␮L extracts wereﬁl-trated by a0.45␮mﬁlter,injected into an ampoule bottle and stored in a refrigerator until analysis.Separation and identiﬁcation of14PAHs were achieved using a HPLC system equipped with aﬂuorescence detector(RF2000)and a UV detector(PDA-100Photodiode Array Detector)from Dionex Corporation,USA.Theﬂuorescence of PAHs was monitored with an automatic adjustment of the wavelengths for each compound according to its retention time.The excitation wavelength was 245nm,while the emission wavelength was425nm.Four wave-lengths(207nm,220nm,230nm,254nm)of the UV detector were selected.A gradient with acetonitrile and water was applied for sep-aration of the analytes:60%acetonitrile and40%water in0–3min; 60%acetonitrile and40%water in3–15min;100%acetonitrile and 0%water in15–38min;60%acetonitrile and40%water at38min. Theﬂow rate of mobile phase was set at1mL min−1.S.Kong et al./Journal of Hazardous Materials183 (2010) 70–8073Quantiﬁcation of PAHs was standardized by the retention times and peak areas of the calibration standards.In all analyses,a proce-dural blank was performed periodically to conﬁrm that there was no contamination.An external standard mixture of selected PAHs which was diluted to500␮g mL−1by acetonitrile was used.Concentrations of14PAHs were quantiﬁed according to their elution orders as followed:napthalene(Nap),acenapthene(Ace), phenanthrene(Phe),anthracene(Ant),ﬂuorene(Flu),pyrene(Pyr), benzo[a]anthracene(BaA),chrysene(Chr),benzo[b]ﬂuoranthene (BbF),benzo[k]ﬂuoranthene(BkF),benzo[a]pyrene(BaP), dibenzo[ah]anthracene(DbA),benzo[ghi]perylene(BghiP), indeno[1,2,3-cd]pyrene(Ind).Data handling and statistical analysis were performed using the Statistical Package for Social Sciences software(SPSS version13.0).2.4.Quality assuranceThe recovery test was performed by spiking known amounts of a mixture of PAHs and then the spikedﬁlter was treated the same way as mentioned above.The recovery experiment was repeated four times.When the concentrations of internal standards were 0.500mg L−1,the recovery for each PAHs fell between86%and95%, and the relative standard deviation was less than10%.Field blank ﬁlters were placed unopened next to the samplers for the dura-tion of sampling,after which they were returned to the laboratory and treated as regular samples to ensure that there was no sig-niﬁcant background boratory blanks(cleanﬁlters) were extracted and analyzed with every10samples.None of the target compounds was found in the blankﬁlters.Consequently,the data was not subjected to any blank correction.3.Results and discussion3.1.General characteristics of total PAHs inﬁne and coarse particulate matterConcentrations of14PM-bound PAHs obtained in this study are presented in Table1,arranged by sampling sites.The total PAHs concentrations of PM2.5and PM2.5–10were in the range of75.32–1900.89ng m−3and16.74–303.24ng m−3,respec-tively.The highest concentrations for PM2.5and PM2.5–10were both found at a residential/commercial area(site7,ZQ).The ZQ site held heavy trafﬁc with tens of boilers for hotel and bath-house as well as lots of barbecue plots.At the same time,it was2km away from Fushun power plant,which emitted about 5000tons of soot each year accounting for16%of the total soot emission of Fushun.The lowest concentration detected was at an industrial area(site10,GJZ)and a residential area(site9,JZJ)in Dalian and Jinzhou for PM2.5and PM2.5–10,separately.Average con-centration of individual PAHs in PM2.5and PM2.5–10varied from 1.64ng m−3(NaP)to128.09ng m−3(Flu)and from1.28ng m−3 (Ant)to12.60ng m−3(Flu).BaP had mean value of21.40ng m−3 for PM2.5,which exceeded10ng m−3,the state recommended air quality standard for BaP as day average[34].It was observed that in theﬁne fraction,the highest concentra-tions of PAHs compounds were Flu(23%),Pyr(21%),Ace(8.3%),Chr (7.9%)and BaA(7.4%)which were associated with coal combustion sources[22].The other nine compounds represented about32.4% of the total concentration of this fraction.In the coarse fraction the dominant compounds were Flu(19.8%),Phe(19.0%),Pyr(16.7%), Ace(7.4%)and Chr(6.0%)indicating that coal combustion was one of the main sources[22]and the other nine compounds represent about31.1%of the total concentration of this fraction.Flu,Pyr,Ace and Chr were also observed as predominant compounds in Xiamen [1],Hongkong[24]and Zonguldak[38]where the contribution of coal combustion,cooking sources and residential heating should not be ignored.Yet some other studies found Ind,BbF and BghiP were the abundant species in Flanders[4],Taichung[10],Sao Paulo [13],Porto Alegre[13]and Rio de Janeiro[18]where vehicular emis-sion was the main source for particulate PAHs.Different sources indicated that there were different inputs of PAHs in urban area.Sum of the carcinogenic PAHs(CANPAHs)including BaA,BbF, BkF,BaP,DbA and Ind accounted for28.8%and23.9%of the total PAHs concentrations inﬁne and coarse particulate matter,respec-tively.The obtained results suggested that coarse fraction can be hazardous to human health as theﬁne one.It also reﬂected PAHs with higher rings tend to be strongly absorbed byﬁne air particles, which was similar to the research of Wang et al.[5].Another criterion to characterize each fraction was to group the PAHs compounds that were combustion derived,including Flu,Pyr, Chr,BbF,BkF,BaA,BeP,BaP,Ind and BghiP[13].In this study,we summed all the species except for Chr and BeP.The sum of the main combustion-derived PAHs concentrations(COMPAHs)cov-ered69.8%,54.1%,70.2%and68.4%of the total PAHs in PM2.5for spring,summer,autumn and winter,respectively.It was60.3%, 43.8%,64.7%and58.0%for PM2.5–10.These proportions indicated that there was a clear difference in summer from the other seasons. Rogge et al.[39]determined the value of COMPAH/ PAHs ratio for non-catalyst(0.4)and catalyst-equipped(0.5)automobiles and for heavy-duty diesel trucks(0.3).In this study,the lower value of COMPAH/ PAHs in summer meant that vehicular emissions espe-cially from catalyst-equipped vehicles may be a contribution while in other seasons emission sources were more complex.Although it was pointed out that results on atmospheric PAHs could differed by40%depending on sampling system,extraction solvents,analytical techniques and detectors[40],and also PAHs determined in airborne particles were inﬂuenced by regional cli-matic as well as source characteristics[13,41],the comparison was conducted with others as listed in Table1in Supplementaryﬁle to better understand the atmospheric particulate PAHs levels in Liaoning Province.The PAHs concentrations observed in this study were comparable to those reported in Beijing[5]and Taichung[23] but were signiﬁcantly higher than those in urban environments of Hongkong[29]and Zonguldak[38].Higher PAHs levels in this region were likely attributed to the combination of dense heavy industries,huge coal consumption due to long heating period, poorer atmospheric dispersion of pollutants,washout effects and less weak photo-degradation.In general,the averageﬁne particulate PAHs concentrations were all higher than coarse particulate PAHs concentrations [19,23,24,26,27,29].Except NaP,the other13kinds of PAHs were consistent with other studies.The amount of PAHs associated with ﬁne particles were47.0%,90.8%,73.8%,89.7%,91.0%,91.9%,92.3%, 92.0%,91.9%,90.0%,90.0%,91.3%,90.7%and90.7%of the total for Nap,Ace,Phe,Ant,Flu,Pyr,BaA,Chr,BbF,BkF,BaP,DbA,BghiP and Ind,respectively.Fang et al.[10]gained the similar results in Beijing that almost all the PM2.5concentrations of individual PAHs were higher than those in the coarse fraction,except for NaP,Ace, BaA and BbF.Zhou[25]pointed approximately45.0–67.8%of total PAHs were present in the particles size less than1.1␮m,while the values were68.4–84.7%for the particles size less than2.0␮m in Beijing.The results showed that total PAHs existed predominantly inﬁne particles,which were strongly related to a potential health risk.While Miguel et al.[44]observed higher PAH concentrations in coarse fraction and attributed this difference to chemical reactions which depleted PAHs fromﬁne fraction.PAHs condensing on the surface of coarse fraction,dust resuspension by wind and vehicle emissions were also contributions to PAHs in coarse fraction[13].Fig.2shows the spatial comparison of PAHs and BaP inﬁne and coarse fraction in theﬁve cities.The concentrations of total PAHs and BaP in theﬁne fraction were higher than those in the coarse fraction and theﬁne to coarse ratio ranged from3.3to9.8for PAHs74S.Kong et al./Journal of Hazardous Materials183 (2010) 70–80Fig.2.Spatial comparison of PAHs inﬁne and coarse particulates inﬁve cities.The top line and symbol graph shows the percentage of BaP in PAHs forﬁne and coarse particulates.The bottom column represents the percentage of PM2.5and PM2.5–10for PAHs and BaP inﬁve cities during sampling periods and the bottom line and symbol graph reﬂects theﬁne/coarse ratio.The blue box means PAHs distribution inﬁne and coarse particulate matter for each city and the red one is the representation of BaP. The left ellipse represent the percentage for BaP in PAHs onﬁne fraction in every city and the right one shows the percentage for BaP in PAHs on coarse fraction.and from5.9to12.0for BaP,respectively.On theﬁne fraction,the BaP accounted for2.7–6.7%of PAHs with value2.2–5.7%on the coarse fraction.3.2.Temporal variation for PAHs inﬁne and coarse fractionSeasonal variations have been widely reported for many stud-ies and the variability has been found to be mainly dependent upon the unique climatic changes and anthropogenic activities of the sampling sites under investigation[24].In Liaoning,there are obvious four seasons with winter(from December to February), spring(from March to May),summer(from June to August)and autumn(from September to November).The results as illustrated in Fig.3indicated that lower PAHs concentrations were observed in July(summer)and April(Spring)while higher PAHs concentra-tions occurred in January(winter)and October(autumn)for both ﬁne and coarse particulates.Higher PAHs concentrations in winter and lower concentra-tions in summer were also widely observed in some Asia cities like Guangzhou[2],Taichung[10],Shizuoka[19],Hongkong[24],Bei-jing[25],Zonguldak[38],Delhi[45]and Kaohsiung[46]and cities in other continents such as Atlanta[11]and Florence[31].For this reason we calculated the winter to summer ratio(w/s)as shown in Fig.4for bothﬁne and coarse particulates.For total PAHs,theﬁne fraction had a ratio that varied from6.5(at GJZ)to125.8(at ZQ)and the coarse fraction had a ratio that varied from1.7(at JZJ)to37.6 (at ZQ).This was in the same or higher level than that in Xiamen [1](w/s:2.0–15.8),Augsburg[15](w/s:8–20),HongKong[24](w/s: 1.4–2.4),Birmingham[28](w/s:4.9),Zonguldak[38](w/s:7.0–70.7 for PM2.5,1.5–12.0for PM2.5–10)and Bursa[47](w/s:8–30).Highest w/s ratio at site ZQ was related to its surrounding circumstances as explained rge coal consumption may explain the higher winter/summer ratio at this site.Site GJZ is near to sea.Therefore, the pollutants could be easily dispersed by the sea-breeze[2].Source emissions and meteorological conditions as well as gas-particle partitioning may result in winter and summerdifference Fig.3.Seasonal concentrations of atmospheric PAHs at10sites forﬁne(a)and coarse particulate matter(b).The tops were for April,July and October.of PAHs concentrations[2].Emissions increased obviously owing to the fossil fuel usage for space heating purposes[3,9,19,21,25] during its4-month long heating periods in Liaoning Province which was one reason for the higher concentrations in winter.The cold start conditions for the vehicles in winter may also contribute to the higher PAHs concentrations[11,25,48].Lower temperatures and atmospheric mixing heights as well as decreased photochemical oxidation intensity can also explain the higher PAHs concentrations in winter[9].A higher ambient temperature could change the distribution of PAHs between the gaseous and particulate phases by increasing the vapour pressure of pollutants that adhered to atmospheric aerosols and favouring the volatilization of PAHs from the particulate to gaseous phase,but it could also increase the mixing height of the atmosphere result-ing in excellent dilution and dispersion of PAHs and hence reduce them[1,24].Furthermore,low atmospheric temperature can affect the distribution of PAHs between the gas and particle phases and result in a relatively larger portion of PAHs partitioning to the particle phase in winter[10,11].There was a negative correlation between PAHs and temperature in many studies[1,2,4,9,20,21]. Greater wind speed could reduce PAHs levels by diluting air mass。