Free energy of an SU(2) monopole-antimonopole pair
KOH活化制备烟杆基活性炭的炭化过程
第37卷第6期2009年6月 化 学 工 程CHE M I CAL E NGI N EER I N G (CH I N A ) Vol .37No .6Jun .2009基金项目:国家自然科学基金资助项目(20167001);高等学校优秀青年教师教学科研奖励计划资助作者简介:张利波(1977—),男,博士,副教授,主要从事碳材料制备与应用,E 2mail:libozh77@yahoo ;彭金辉,通讯联系人,E 2mail:jhpeng@kmust .edu .cn 。
K OH 活化制备烟杆基活性炭的炭化过程张利波,彭金辉,李 宁,夏洪应,李 玮,曲雯雯,朱学云(昆明理工大学材料与冶金工程学院,云南昆明 650093)摘要:为了揭示K OH 活化烟杆制备活性炭中炭化阶段的反应机理,利用热重法对氮气气氛中烟杆和浸渍K OH 的烟杆在不同升温速率下(分别为5,15,30K/m in )的热解过程进行了研究。
结果表明,随着K OH 的加入,降低了烟杆主要成分的分解温度,为炭化之后的活化反应奠定了重要基础。
采用Coats 2Redfern 模型对实验数据进行处理,得出了烟杆和添加K OH 的烟杆的热解表观活化能和指前因子,建立了热解动力学模型,发现烟杆及添加K OH 的烟杆热解的主要阶段分别可由一段1级反应和2.5级反应过程描述,K OH 的存在可将烟杆炭化阶段的活化能降低约30kJ /mol,动力学参数存在补偿效应。
关键词:烟杆;K OH;炭化过程;热解;动力学;动力学补偿效应中图分类号:T Q 351.21 文献标识码:A 文章编号:100529954(2009)0620059204Carbon i zati on process i n preparati on of acti vated carbon fro mtobacco ste m s with K OH 2acti vati onZHANG L i 2bo,PENG J i n 2hu i ,L I N i n g,X I A Hong 2y i n g,L IW e i ,QU W en 2wen,ZHU Xue 2yun(Faculty of Materials and Metallurgical Engineering,Kun m ing University of Science and Technol ogy,Kunm ing 650093,Yunnan Pr ovince,China )Abstract:I n order t o reveal the mechanis m of carbonizati on p r ocess in p reparati on of activated carbon fr om t obacco ste m s with K OH 2activati on,the pyr olytic p r ocess of t obacco ste m and that i m p regnated with K OH was carried out by using ther mo 2gravi m etric analyzer at different heating rates of 5,15,30K/m in in N 2at m os phere .The te mperature of pyr olytic reacti ons of main component of t obacco ste m s can be reduced in the p resence of K OH,which lays the i m portant foundati on of the activati on reacti on after ward .Coats 2Redfern model was used t o deter m ine the kinetic para meters for the t obacco ste m s with /without K OH,including frequency fact ors and activati on energies .Thepyr olytic kinetic models of t w o sa mp les were set up.The main pyr olytic stages can be described by first 2order and 2.52order gl obal model,res pectively .The results indicate that the pyr olysis activati on energy can be l owered by about 30kJ /mol in the p resent of K OH,and the kinetic para meters exhibit compensati on effects .Key words:t obacco ste m s;K OH;carbonizati on p r ocess;pyr olysis;kinetic;kinetic compensati on effect 高比表面积活性炭具有比表面积大、吸附量高、吸附速度快等特点,在气体燃料的吸附存储、吸附分离、双电层电容器电极材料的制备等诸多方面均表现出广阔的应用前景。
酶辅助超临界CO_2提取柚皮甙的研究
a d o o o a x e me t r s l s g e t d t a h pi z d c n i o sw r b an d a n  ̄h g n le p r n . e u t u g se h tt e o t i mie o d t n e e o t i e s ̄l ws r a me ttmp r — i l o :te t n e ea tr 0 C , p . ue5  ̄ H4 0, a u to n y e e 3 , t ame tt . h, Un e h pi lc n i o s t e 0ly ed mo n fe z me w r % r t n i 2 5 e me d rte o t ma o d t n , h i i l i ra h d 3 6 % , En y e c e . 8 z me—a sse u e e i c a b n d o i e e t ci n o i h r c d o t e t h xr c in sit d s p r r ia c r o ixd xr t fcc o i a i b mn d wi t e e ta t tl a o c h o o se ta t n r t , p o u t u t , t e p o e s i smp e fi x r ci ae t o r d c r y h r c s s i l . pi Ke r s s a d c y wo d : h d o k; n rn i ai g n;c l w l d ga ai n s p r r ia O2f i xr ci n e z me el a l e r d t ; u e c i c C u d e t t ; n甙 ;破壁 ;超 临界二 氧化碳 ;酶
射频技术在皮肤抗衰老方面的应用进展
射频技术在皮肤抗衰老方面的应用进展闫飞【摘要】皮肤衰老主要表现为皮肤松垂、皱纹形成、容量丢失,是随着年龄的增加由多种机制共同作用产生的一种衰老征象.维持或恢复皮肤年轻化,日益受到人们重视,随着研究的不断深入,抗衰老技术日益增多.其中射频技术以其治疗方式简单、安全性好、在面部年轻化方面具有良好的长期效果等特点,而成为目前皮肤年轻化的一项重要的美容技术.大量研究表明,单极到多极射频技术均具有去皱、改善皮肤松弛和肤质的效果,但是也存在治疗后的效果不显著等情况.本文拟综述射频技术在皮肤抗衰老方面的应用进展,以期更好地提高射频技术的临床应用效果.%The hallmark of human skin aging is accumulation of skin laxity, photodamage, wrinkles and an overall decline in skin texture. It is a kind of aging phenomenon along with multiple mechanism. Minimally invasive procedures have gained popularity nowadays. The appeal behind these nonsurgical antiaging procedures is that they are less invasive and require less downtime. Researches show that: both the monopole radiofrequency technology , Bipolar and multi-frequency radiofrequency technology have gained popularity for the treatment of skin laxity of the face. Radiofrequency is currently one of the most important cosmetic techniques, which has good prospect, while the clinical efficacy has yet to be determined significantly. The goal of this review is to summarize the use of radiofrequency technology in the esthetic field and its scientific background and to evaluate the evidence-based efficacy of these devices and to improve the clinical effect of radiofrequency technology.【期刊名称】《中国美容医学》【年(卷),期】2017(026)004【总页数】4页(P132-135)【关键词】射频技术;抗衰老;面部年轻化;联合治疗【作者】闫飞【作者单位】中国医学科学院整形外科医院整形十七科, 北京 100144【正文语种】中文【中图分类】R339.3+8皮肤衰老是一个多因素、多角度的过程,衰老的变化在30岁开始并且在女性绝经期迅速发展。
超亲气泡沫铜纳米线电极电化学还原CO2性能
化工进展Chemical Industry and Engineering Progress2024 年第 43 卷第 3 期超亲气泡沫铜纳米线电极电化学还原CO 2性能王凯1,2,叶丁丁1,2,朱恂1,2,杨扬1,2,陈蓉1,2,廖强1,2(1 重庆大学低品位能源利用技术及系统教育部重点实验室,重庆 400030;2 重庆大学能源与动力工程学院工程热物理研究所,重庆 400030)摘要:利用可再生电能进行电化学还原CO 2被认为是一种有前景的储能和减排技术,但在阴极发生析氢副反应,将降低电化学还原CO 2的性能。
采用泡沫铜为基底制备铜纳米线电极扩展电极的电化学活性面积,然后通过十七氟癸基三甲基硅烷对电极进行亲气处理,使电极表面从疏气状态变为超亲气状态,从而强化气相反应物CO 2传质,增加反应三相接触线,提高电极的电化学还原 CO 2性能。
实验结果表明:与未亲气处理的泡沫铜纳米线电极相比,所制备的超亲气泡沫铜纳米线电极虽然具有较小的电化学活性面积,但其超亲气的特性更有利于CO 2的传质,抑制了电解液中氢离子的传输,有效削弱了析氢副反应的发生。
在电解电位为-1.5V (vs . Ag/AgCl )时,H 2法拉第效率降低了17.7%,电化学还原CO 2性能提升。
关键词:电化学;还原;二氧化碳;铜纳米线;超亲气;传质中图分类号:TQ021.4 文献标志码:A 文章编号:1000-6613(2024)03-1232-09Performance of electrochemical reduction of CO 2 by superaerophiliccopper foam electrode with nanowiresWANG Kai 1,2,YE Dingding 1,2,ZHU Xun 1,2,YANG Yang 1,2,CHEN Rong 1,2,LIAO Qiang 1,2(1 Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Ministry of Education, Chongqing University, Chongqing 400030, China; 2 Institute of Engineering Thermophysics, School of Energy and Power Engineering, ChongqingUniversity, Chongqing 400030, China)Abstract: Electrochemical reduction of CO 2 by renewable electricity is regarded as a promising methodto storage energy and reduce emissions environmental problems. However, the hydrogen evolution sidereaction at the cathode will reduce the performance of electrochemical reduction of CO 2. Nanowires were prepared on the copper foam electrode to expand the electrochemical active area of the electrode. Then, the copper foam nanowire electrode was treated with trimethoxy (1H, 1H, 2H, 2H-heptadecafluorodecyl)silane to make the electrode surface change from aerophobic to aerophilic, which was expected to strengthen the mass transfer of gas-phase CO 2, increase the three-phase contact line of the reaction and further improve the performance of electrochemical reduction of CO 2. Experimental results showed thatcompared with the copper foam nanowire electrode without aerophilic treatment, although the prepared aerophilic electrode possessed lower electrochemical active area, its superaerophilic property was研究开发DOI :10.16085/j.issn.1000-6613.2023-0426收稿日期:2023-03-21;修改稿日期:2023-06-06。
Second organic aerosol formation from the ozonolysis of α-pinene in the presence of dry submicr
D epart me nt of E nvi ronm e ntal Sc ienc e and E ngine er ing, Tsinghua U niv eห้องสมุดไป่ตู้si ty, B ei jing l00084, Chi na. E-m ail: zhaozhe 97@m ails.tsi .c n Re c eive d 13 D e ce mbe r 2007; revi sed 3 F ebruary 2008; a cc epte d 27 Fe brua ry 2008
A bstra ct A n ind oo r chamb er facility is d escrib ed fo r in vestig ation of atmos ph eric aero so l chemistry. Two sets o f α -pinen e ozo no ly sis ex periments were con du cted in th e p resen ce o f d ry ammon iu m s ulfate seed p article: o zon e limited ex periments and α -p in ene limited ex periments. T he con centration of gas ph as e and particle p has e s pecies w as mon itored contin uo us ly by o n-lin e in strumen ts an d reco rded au to matically b y data samp ling s ys tem. Th e evo lu tion of size d is tributio n was measu red by a s cann in g mob ility p article s izer (SM PS), an d α -pinen e con su med w as measu red u sing G C-FID . Seco nd ary organ ic aeros ol (SOA) pro du ced fo r s eed-free s ys tem is 1 00 % organ ic in con ten t, res ulting fro m a s uffi cient su pers atu ratio n o f low v olatility o rganics to pro du ce h omo gen eou s nu cleatio n fo llow ed by co nd ens ation to th e aero so l. Secon dary o rgan ic aeros ol p rod uced in seed ed sy stem is a mixture of org anic an d in organ ic co ns titu ents, in itially fo rms v ia co nd ens ation on to th e in org an ic p articles , an d s ub seq uent g rowth o ccurs via abs orp tion in to th e organ ic s urface coating the in organ ic core. Alth ou gh th e fo rmation pro cess an d the size d is tributio n for s eed-free sy stem and s eeded s ystem is d iff erent, the u ltimate mas s o f SOA fo rmed is equ al, and SOA yield for th e tw o sy stem lo cated in the same reg ress io n lin e w hen us in g o ne-p rod uct mod el, su gg estin g that th e pres ence of d ry ammo nium s ulfate s eed h as n o measu rab le e ffect on th e to tal aeros ol yield , an d the dry seed particle acts s olely as a site up on wh ich org anic dep os itio n o ccurs . Key wo rds: α -p in ene o zon olys is ; s econ dary org anic aeros ol (SOA ); ch amber ex periment; s eed particles
糖蜜酒精废液中大分子焦糖色素模拟物浸出软锰矿的动力学
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( . c o l f e s ya dCh mia En ie r g Gu g i iest, n ig5 0 0 , ia 1 S h o Ch mi r n e c l gn e i , a x v ri Na nn 3 0 4 Chn ; o t n n Un y
糖 蜜酒精废液 中大分 子焦糖 色素模 拟物浸 出软Байду номын сангаас矿 的动力学
粟海锋 吕奕菊 崔勃 焱 王 凡 吕小 艳 文衍 宣 , , , , ,
(.广 西大学 化 学化 工学院,广 西 南宁 500; 2 I 3 04 .广西大学 教 务处,广西 南 宁 5 0 0 ) 3 04
摘 要 :用 收缩芯模型研 究了糖蜜酒精废液 中大分子焦糖色素在硫酸 介质中还原浸 出软锰矿 的动力学,考察 了软锰矿
关键 词:软锰矿 ;糖 蜜酒精 废液;焦糖色素 ;浸 出;动力学 中图分 类号: T 1 .;T 2 .6 Q0 32 Q0 89 :X7 2 9 文献标识码:A
Le c n ne i so o ust y M a r m o e u a r m e f a hi g Ki tc fPyr l ieb co lc l rCa a l o M o a s sAlo l l s e c ho se t r t wa e
粒度 、反应温度 、浸 出时 间、硫 酸浓度和焦糖 色素浓度对锰浸 出速率 的影响。结果表 明锰浸 出速 率随反应温度 、硫酸 浓度 、焦糖色 素浓度的增加和 软锰矿 粒径的减 小而 增加。糖蜜酒精废液 中大 分子焦糖色素还原浸 出软锰 矿属固体产物 层扩 散控制 ,表观活化 能为 5 . J l ,硫酸 和焦糖色 素的表 观反应级数分别为 O 4及 O8 。 67 . ~ 2 k mo . 6 . 3
新托福ETS真题阅读精选56篇词汇终极版龙哥
自由基化学
自由基化学刘有成(中国科学技术大学化学系 合肥 230026) 刘中立(兰州大学应用有机化学国家重点实验室 兰州 730000)刘有成 男(1920111—),安徽舒城人,教授,博士,中国科学院院士,研究方向:有机化学。
刘中立 男(194116—),湖北汉阳人,教授,研究方向:有机化学。
1999210210收稿摘 要 近20年来,中国的自由基化学研究在若干领域取得了重要的进展,包括单电子转移反应,自旋离域取代基参数的建立,自由基的热力学稳定性研究等。
哌啶氮氧自由基与一些生物小分子,如半胱氨酸、谷胱甘肽、抗坏血酸等,在溶液及胶束中的反应经过动力学研究证明反应的单电子转移机理。
哌啶氧铵盐氧化芳香胺和含氮、硫芳杂环为相应的自由基正离子,首次报道了噻蒽及甲基吩噻嗪自由基正离子与其中性母体之间电子转移的同位素效应。
通过对对位取代的Α,Β,Β2三氟苯乙烯热环加成的动力学研究,建立了一套新的自旋离域取代基参数ΡJJ ・,与取代基的极性效应分开,并用一个双参数方程对一些自由基反应进行相关分析,取得了成功。
研究了吸电子取代基和给电子取代基对自由基热力学稳定性的影响,证明了C lass O 自由基的存在。
关键词 自由基 电子转移 取代基效应Abstract D u ring the past tw o decades i m po rtan t advances have been m ade in som e areas of freeradiacal research in the Peop le’s R epub lic of Ch ina ,i .e .single electron tran sfer reacti on s ,theestab lishm en t of sp in 2delocalizati on sub stituen t con stan ts ,and the study of thermodynam ic stab ilities ofradicals.It has been show n th rough k inetic studies that the reacti on s betw een p i peridine n itrox ides w ith som e b i o logical s m all mo lecu les ,e .g .cysteine ,glu tath i one ,asco rb ic acid ,in so lu ti on o r m icelles p roceed by electron tran sfer m echan is m .P i peridine oxoammon ium salts ox idize arom atic am ines and N ,S 2con tain ing heterocycles to the co rresponding radical cati on s ,and the iso tope effects in electron tran sfer reacti on s betw een th ian th rene and N 2m ethylpheno th iazine radical cati on s and their respective neu tral paren t mo lecu les have been repo rted fo r the first ti m e .T h rough k inetic studies on the therm alcycloadditi on reacti on s of Y 2sub stitu ted Α,Β,Β2trifluo ro styrenes ,a new scale ΡJJ ・of sp in 2delocalizati on sub stituen t con stan ts is estab lished ,w h ich is separated from the sub stituen t po lar effect ,and a dual 2param eter equati on is u sed fo r co rrelati on analysis of a num ber of free radical reacti on s w ith success.By study of the effects of E W G and ED G sub stituen ts on the thermodynam ic stab ilities of free radicals ,the ex istence of C lass O radicals has been p roved .Key words free radical ,electron tran sfer ,sub stituen t effect .新中国成立以来,尤其是改革开放以来,我国的有机自由基化学研究取得了重要的进展,引起了国际学术界的关注。
兔儿伞不同溶剂提取物的体外抗氧化作用研究(精)
兔儿伞不同溶剂提取物的体外抗氧化作用研究[ 10-08-26 15:15:00 ] 编辑:studa20作者:李加林,刘丽华,吴素珍,范启兰,陈水亲【摘要】目的探讨兔儿伞乙醇、丙酮、醋酸乙酯、水提取物体外抗氧化能力。
方法利用微波辅助提取法分别得到了兔儿伞乙醇提取物、丙酮提取物、醋酸乙酯提取物和水提取物,采用Fonton反应体系产生羟基自由基和邻苯三酚自氧化产生超氧阴离子自由基。
结果4种提取物对羟自由基、超氧阴离子自由基(O2- ·)均有清除作用,其中以乙醇提取物的效果最佳。
结论兔儿伞可作为抗氧化物质资源,有一定的开发利用价值。
【关键词】兔儿伞;自由基;抗氧化活性自由基(free radical) 也称活性氧,很多情况下,它都缺少一个电子,处于不稳定的状态。
不稳定的自由基会从周围的物质中夺取电子配对,这种行为就是自由基的氧化作用。
被夺走电子的物质,又去抢夺其它物质的电子。
就这样,争夺电子的连锁反应逐渐扩散到各处,细胞一个一个被氧化,从而失去了其正常功能。
越来越多的科学研究证实自由基是人体疾病和衰老的直接制造者。
人只要活着,自由基就在不断生成。
自由基一旦大量产生,超过身体内酶所能处理的程度,人的健康就会亮起红灯,出现癌症、动脉硬化、糖尿病、白内障、风湿性关节炎、巴金森氏症等多种疾病[1]。
动物实验也指出,寿命的长短与自由基的产生及人体内抗氧化剂的浓度确实有密切的关联;流行病学与临床研究报告也显示,如果人体内有足够的抗氧化剂,则可降低多种疾病的罹患几率。
然而研究发现,合成抗氧化剂对人体具有潜在的威胁,如BHA可造成大鼠前胃增生、乳状瘤甚至癌变,在日本已被禁用;BHT能使人的Wl-38胚胎细胞分裂后期发生阳性的染色体异常,甚至导致死亡,因此在美国和日本已经停止使用。
随着消费者自身健康意识的提高,天然抗氧化剂日益受到重视[2~4]。
因此,研究开发广谱、高效、安全的天然抗氧化剂,已经成为当今的研究热点之一。
硫酸镁建筑材料制备及性能研究
硫酸镁建筑材料制备及性能研究马梦娜(陕西工业职业技术学院,咸阳712000)摘要:硫酸镁水泥具有质轻、高强、高环保以及低耗能等特点,是一种新型的胶凝材料,其在建筑领域有着重要的应用前景。
本论文采用发泡技术,选用硫酸镁水泥作为主要的原材料,制备硫酸镁基轻质材料,并通过单一变量的实验方法,研究了不同的稳泡剂剂量、水灰比条件下制备的材料的力学性能以及软化系数性能,为以后的硫酸镁建筑材料的研究奠定了基础,同时为以后的应用提供了理论和试验的依据。
关键词:硫酸镁;材料表征;力学强度;衍射分析中图分类号:TU528文献标识码:A文章编号:1001-5922(2021)01-0012-04 Study on Preparation and Performance of MagnesiumSulfate Building MaterialsMa Mengna(Shaanxi Polytechnic Institute,Xianyang712000,China)Abstract:Magnesium sulfate cement has the characteristics of light weight,high strength,high environmental pro⁃tection and low energy consumption.It is a new type of cementitious material and has important application pros⁃pects in the field of construction.This paper adopts foaming technology,selects magnesium sulfate cement as the main raw material,prepares magnesium sulfate-based lightweight materials,and through a single variable experi⁃mental method,the mechanical properties and softening coefficient performance of materials prepared under differ⁃ent foam stabilizer dosages and water-cement ratio conditions were studied,which laid the foundation for future re⁃search on magnesium sulfate building materials,and at the same time provided theoretical and experimental basis for future applications.Key words:magnesium sulfate;material characterization;mechanical strength;diffraction analysis0引言我国城镇化的不断发展,人民生活质量的不断提高,使得国民对于环保的意识逐渐提高。
芦苇硫酸盐浆氧脱木素动力学的研究(Ⅱ)——碳水化合物降解动力学
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Contemporarily, there is a heated discussion concerning whether moving to a new town is worthwhile for we may lose the old social circle. Numerous people hold the opinion that people will surely lose their old social circle for the reason that we will be far away from our former living place and might gradually forget the bosom friends and colleagues. However, as far as I concerned, we will not lose our old social circle. And here are several reasons.To start with, we won't lose our old friends for the reason that the communication equipment is well developed nowadays. So we can get in touch with each other wherever you are and whenever you want. Take my friend Peter as an example, we have been best friends for 12 years. But 3 years ago, he moved to Chicago to study in a university. We haven't seen each other for 3 years in total. However, we chat on the internet every day even if we have time difference. I strongly believe that our friendship can stand the test of time.In addition, if we are fully into a new environment, we can easily find a new job and begin a brand new life. Also, we will establish a new social circle in a short time and make more friends. A case in point is that my cousin Jason once traveled to Kunming, a wonderful city in China. He fell in love with that amazing city and decided to move there as soon as possible. As a result, he is familiar with his dream city now and had found a proper job in a big company. I guess now Jason is having a wider social circle than before and realize his goal in life.Admittedly, we will find it hard to get used to a new environment and may have difficulty finding the common topics with your old friends.But if we just stay in the original city and don't move anywhere, we do will live a life of ease. However, moving to another city is worthy to be experenced for we just have one life. Additionally, as well as we are active and positive people, we will not lose the old social circle for sure.Judging from what has discussed above, we could undoubtedly draw the conclution that it is a good thing for us to move to a new city.397 wordsBy ClaireVannQuestion:Do you agree or disagree with the following statement? It is often not a good thing for people to move to a new town or a new country because of the lose of old social connection.写作提纲我不同意开头1.没有失去老朋友,现在通信设备很发达,可以随时联系2.得到新的工作,建立新的社交圈3.是一种新的生活体验,人生就需要这种体验。
防风中色原酮类化合物的抗氧化活性研究
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运动对抗氧化酶活性影响的研究进展
运动对抗氧化酶活性影响的研究进展第20卷第1期2005年3月山西师大体育学院学报JournalofPhysicalEducationInstituteofShanxiTeachersUniversityV o1.20No.1Mar.2005运动对抗氧化酶活性影响的研究进展钱荣,杨德顺(1.上海体育学院,上海200438;2.蚌埠医学院,安徽蚌埠233000)摘要:剧烈运动时自由基的大量生成与清除能力下降是导致运动性疲劳和运动性损伤的主要原因之一.抗氧化酶在保护机体免受自由基损伤中发挥着重要的作用.运动训练能增加抗氧化酶的活性,提高机体清除自由基的能力.不同抗氧化酶对不同运动训练的反应不同.本文通过文献查阅的方法,对国内外学者近年来关于运动训练对抗氧化酶影响的研究进行综述,为该领域的研究提供一定的理论指导.关键词:运动;自由基;抗氧化酶中图分类号:G804文献标识码:A文章编号:1008—8571(2005)01—0l13—02 AdvancesinStudiesontheEfiectofExerciseontheActivityofAntioxidamEnzymesQIANRong.Y ANGDe-shun(ShanghaiInstituteofPhysicalEducation.Shanghai200438.China)Abstract:Strenuousexercisemayinducemuchmorefreeradicalsproductionanddecreasetheabilityfor scavengingfreeradicals,whichisoneofthemajorreasonsofexercisefatigueandinjuries.Antioxidanten zymes playanimportantroleinprotectingtissuesfromfreeradicaldamageduringexercise.ExercisetrainingCa nin- creasetheactivityofantioxidantenzymesandenhancetheabilityforenzymaticscavengingoffreeradica ls.The reactionsofdifferentantioxidantenzymestodifferentexercisesappearedvariously.Bythemethodofco nsultingliteraturematerials.thisarticlereviewsbrieflythenewstudiesofintemationallearnersconcenfingtheeff ectofexerciseontheantioxidantenzymes,whichprovidescertaintheorydirectionsforthefuturestudiesinthis field.Keywords:exercise;freeradicals;antioxidantenzymes运动训练中随着运动强度,运动时间的增加,自由基产生急剧上升,当体内与之相对抗的清除自由基的抗氧化酶活性下降时,可导致机体氧化应激的发生,对组织器官造成不利影响,是引起运动性疲劳,组织损伤的主要原因之一.机体抗氧化酶系统主要包括超氧化物歧化酶(SOD),谷胱甘肽过氧化物酶(GSH—Px),过氧化氢酶(CA T).不同运动模式对机体抗氧化酶活性的影响不同.不同器官组织中的同一种酶受运动影响的表现也不同.本文通过文献查阅的方法,对近年来不同运动训练对机体抗氧化酶的影响的研究作一综述,以更好地了解抗氧化酶在对抗自由基损伤中所发挥的作用.1不同运动训练对SOD活性的影响SOD是需氧生物体内数千种酶中底物为氧自由基的唯一的酶,该酶对底物显示绝对专一性,其作用是歧化超氧阴离子自由基(O:一?)生成过氧化氢(H:O:).SOD是评定机体抗氧化能力的经典指标.人体具有三种SOD同功酶:存在于细胞浆的CuZn—SOD,存在于线粒体的Mn—SOD,还有一种Fe—SOD,发现最晚,动物组织中不含Fe—SOD.关于运动对SOD活性影响的研究,国内外学者报道不一.一般认为,一次急性运动可引起心肌,骨骼肌和肝脏等组织SOD等抗氧化酶的活性增高.但对于不同的组织和抗氧化酶,激活阈值和升高幅度可能有不同.陈刚等报道大鼠耗竭游泳时心肌线粒体SOD活性和脂质过氧化程度呈负相关;Powe~等…研究发现强度越大和/或每日运动持续时间越长提高骨骼肌SOD的活性越明显.但也有不同的报道.如林丽雅等发现,中跑,羽毛球.柔道运动员一次极限负荷收稿日期:2004—09—15作者简介:钱荣(1972一),女,安徽蚌埠人,上海体育学院硕士研究生,主要从事运动人体科学的研究.114?山西师大体育学院学报2005年3月后SOD活力无显着改变,提示长期的专项运动训练可使SOD活性产生适应.倪耀华报道血浆SOD在30%VO一,70%VO,90%VO2三种不同的强度条件下运动时,在70%VO一时,MDA升高的同时SOD水平下降,可能与运动强度及运动时间有关.越来越多的研究证实有氧锻炼可以提高组织SOD活性.如王胜奎等发现,长期坚持健身锻炼的老人,其血清中SOD活性增加.这与刘洪珍的报道不一【5j,发现7周的有氧耐力训练并没有提高大鼠肌组织SOD活性,反而略有下降,与训练周期较短,运动量不够有关.关于运动对SOD同工酶的报道不多见,ChitoseNakao将小鼠进行6周游泳训练后,CuZn—SOD仅在肾脏组织中明显增加,心肌,肺和肝组织中明显下降,Mn—SOD在肺,肾,骨骼肌明显增加,但在肝中显着下降,提示不同组织对游泳训练的反应不同,肾脏可能是适应氧化应激状态的最敏感的器官.也有学者认为存在于线粒体的Mn—SOD与VO之间呈线性正相关,推测SOD活性在某种程度上可反映有氧代谢能力.2不同运动训练对GSH—Px活性的影响目前认为,运动或运动训练对机体抗氧化机制的影响中,谷胱甘肽系统的反应最为敏感.曾有报道体外实验证明GSH—Px在防止自由基损伤的作用中比SOD和CA T大, 它以GSH(还原型谷胱甘肽)为底物,特异性地催化GSH对过氧化氢的还原反应,使GSH氧化成GSSG(氧化型谷胱甘肽),从而起到保护细胞膜结构和功能完整的作用.因此根据GSH:GSSG比值的变化可以更全面地判断GSH—Px的活性变化.研究者一致认为,长期大强度有氧训练,能增强机体氧化应激程度,使机体的抗氧化能力产生适应性变化.季丽萍等对大强度间歇训练和持续训练大鼠肾脏组织自由基及抗氧化酶活性进行比较时发现,GSH—Px与SOD在对抗自由基的过程中,两者相互协作,同时GSH—Px又滞后于SOD,表现为运动后SOD下降而GSH—Px上升.史亚丽等认为在较短时间运动后机体GSH—Px活性升高,而较长时间亚极量运动后尤其是力竭性运动后机体GSH—Px活性下降;这与刘洪珍等的研究报道不一,他采用由亚极量负荷到极量负荷递增直至力竭的运动模式,发现GSH—Px活性随运动负荷的加大而升高.在关于耐力运动对GSH—Px活性影响的报道中,刘洪珍发现短时期有氧耐力训练对GSH—Px活性影响不显着,而曹国华等报道,有氧运动后自由基防御体系中GSH—Px活力显着提高,表明与运动强度或持续时间有关.郭林等学者认为,仅以组织SOD或GSH—Px等数量的单纯相加作为对抗自由基能力的唯一指标,而忽略了MDA 水平的变化,是不全面的,而应将SOD/MDA,GSH—Px/MDA 的比值变化作为综合衡量自由基代谢指标,但目前这一观点并未达到共识.3不同运动训练对CA T活性的影响CA T在细胞内主要与线粒体及过氧化物酶结合,在红细胞中CA T呈溶解状态.CA T能将细胞代谢所产生的毒性物质I-I202迅速加以清除,从而起到和GSH—Px共同保护巯基酶,膜蛋白和解毒的作用.据报道,红细胞中CA T活性在抗氧化中所起的作用是血清中CA T活性的3000多倍.有关运动对CA T活性影响的研究在20世纪80年代后逐渐增多.如Salminen和V ihko报道,持续3周的运动训练xCd,鼠骨骼肌中CA T活性没有影响;Terblanche【13]发现1小时的游泳训练使雌性和雄性大鼠心脏,肝脏,肺,肾脏组织的CA T活性显着增加,并且雌性和雄性大鼠有明显差异.国内在这方面的研究报道较少.刘洪珍实验发现,人体内CA T的活性对运动刺激非常敏感,有氧运动锻炼能够明显促进机体CA T活性的升高,增大运动强度其效果更为明显;在对48名少年进行亚极量和极量两种负荷的测试中,CA T活性在亚极量负荷时较运动前稍有下降,而极量负荷时又非常显着地升高¨;王梅¨研究发现经过7周有氧耐力训练的大鼠其骨骼肌中CA T活性显着高于对照组,对运动训练的敏感性较高.以上研究证明运动中CA T活性有其特异性,并与运动强度和持续时间密切相关.4小结运动对抗氧化酶影响的研究近10年已取得可喜的进展,从目前的研究结果分析,机体不仅对运动刺激能产生应激性,更为重要的是具有适应性.随着运动强度的增加和持续时间的延长,机体在对抗自由基的过程中,抗氧化酶活性从代偿反应发展到失代偿反应,在不同的运动条件下,活性发生着相应的变化.但迄今为止,国内外关于运动与抗氧化酶之间相互关系的实验学研究的文献,主要局限于动物实验,在人体的研究尚不完善,有关运动员的研究更少,研究的结果也不尽一致.运动模式多为一次性急性运动,耐力训练或递增负荷力竭训练,因而对运动训练实践的指导难免具有片面性.这也为今后的工作指明了研究方向,在探讨运动对机体抗氧化酶系统影响的研究中,扩大实验对象的范围及涉及的运动项目,为全面揭示运动与抗氧化酶之间的关系提供丰富的实验依据.参考文献:[1]Powe~SK,CriswellD,LawlerJ.Influenceofexerciseandfiber typeOilantioxidantenzymeactivityinratskeletalmuscle[J].AmJ Physiol,1994,266,(2):375~380.[2]林丽雅,邓京捷,周卫海.一次极限运动对运动员体内的自由基生成与清除的影响[J].体育科研,1996,17(4):45~48.[3]倪耀华.运动强度对血浆脂质过氧化物和超氧化物歧化酶活性的影响[J].中国运动医学杂志,1992,11(2):118.[4]王胜奎,李爱华,健身锻炼对老年人身体素质的影响.Ⅱ.酶和自由基[J].中国运动医学杂志,1999,18(1):89~90.[5]刘洪珍,郭建军,武桂新.不同有氧耐力训练对肌组织自由基代谢和抗氧化系统的影响[J].中国运动医学杂志,2000,19 (1):99~100.(下转第128页)山西师大体育学院学报2005年3月互转化上,如武术中的进与退,上与下,往与来,开与合,虚与实等对立面的不断转化,形成鲜明的节奏. 没有节奏,就不可能给人以美感.3.3协调多样统一是形式美规律中最高级的表现形式.它概括了形式美法则中的多种类型,既包含了对称,平衡,整齐一律等和谐统一的方面,又容纳了对比,比例,节奏,主次等变化多样的方面”.反映在整套演练时的协调主要表现在:(1)运动员“形”与”神”的协调.竞技武术套路对形神协调的要求是”形神兼备”,”形”与”神”是与表现攻防格斗含义紧密关联的.运动员在演练中要将自己”置于一个战斗的场合”,并通过”形”与”神”的协调来达到”形神兼备”的,体现武术套路的和谐之美.在演练同一套路上,往往会因不同的运动员而产生不同的风格与神韵,这与运动员演练技术水平的高低, 对演练内容与内涵的理解程度以及个人的身体素质,气质有一定的关系.因此,运动员在追求”形美”的同时,要根据自身的条件,充分发挥出”神美”,做到有自身特点的”形”与”神”的”和谐”.(2)人与器械的协调.器械是指刀,剑,枪,棍等长短器械.人与器械的和谐是指人体动作与器械协调一致所表现出来的美学特征.武术运动中各种长短,软硬器械,在古代是一种进攻和防守的武器,使用器械的熟练程度是评定一个人的武功高低最重要的条件之一.因此,如何熟练掌握各种器械使手眼身步等身体的动作与器械协调一致,对于发挥各种器械的功能就显的格外重要.如剑术练习中,要做到剑与身,剑与手,剑与指,剑与眼,剑与意的协调配合;棍术练习中,以腰为轴,以头领身,棍随身转,眼随棍行,身棍融合,手足应心,意到棍到,意停棍停.棍术中人与器械协调一致,使全身之力贯于棍体,似觉棍是手臂的伸延,伸缩自如,力点准确,给人以身械协调的美感.(3)动作与音乐的协调.音乐和竞技武术套路都是表演性艺术,有着不同的特点.音乐长于抒情,表现性强,能引起人们的自由联想,可导致明确的或朦胧的确定的或不确定的情绪产生. 音乐富有生命力的音调和旋律,能够给人以强烈的震撼和巨大的感染.音乐这一表达思想情感的听觉艺术与竞技武术套路这一展示攻防格斗技艺的视觉艺术的融合,会产生强烈的艺术魅力.伴随着运动员的动作对观众的视觉输入,音乐伴奏同时给予观众听觉输入.这种完美的视听结合,将会赋予竞技武术套路生机勃勃的活力.总之,只有深刻认识规定动作指标的美学内涵以及在体育运动中的体现,才能在竞赛中获得好的成绩,毕竟在难度分相当的情况下,还要看演练水平的高低.参考文献:[1]刘叔成.美学基本原理[M].上海:上海人民出版社,1987.81. [23许自强.美学基础[M].北京:首都经济贸易大学出版社, 2003.118.[3]曾扬.试论”松,顺,通”在武术中的作用[J].成都体育学院学报,1994(4):54—56.[43赵道新.辨劲[J].武魂,1996(1):36.[5]温力.武术的劲力[J].精武,1987(1):30—31.[63国家体育总局武术运动管理中心.武术竞赛规则(试用本) [M].北京:人民体育出版社.2004.(上接第l14页)[11][6]ChitoseNakao,eta1.Effectsofswimmingtrainingonthreesuperox- idedismutascisoenzymesinmousetissues.J.App1.Physiol,2000.[12] 88,(2):649-654.[7]隋波.运动对自由基生成及超氧化物歧化酶活性的影响[J]. 山东体育学院学报,1997,13(2):37—40.[13][8]傅静波,刘洪珍.少年在亚极量,极量负荷运动下血中MDA, GSH,SOD和CA T的变化[J].中国体育科技,2000,36(8):34—38.[14][9]季丽萍,冯照军.大强度间歇训练和持续训练对大鼠肾脏组织自由基代谢及其防御系统的影响[J].中国运动医学杂志.2O04,23(1):87—89.[15][1O]史亚丽.耐力运动与机体抗氧化酶[J].北京体育大学学报, 1999(1):34—36.刘洪珍.有氧运动锻炼对人体自由基代谢及其相关酶系的影响[J].中国运动医学杂志,2001,20(4):425—427.曹国华,陈吉棣.运动,锌铜营养与自由基代谢一Ⅱ.一次急性有氧或无氧运动对人体内自由基生成与清除的影响[J].中国运动医学杂志,1991.10(1):l一3.S.E.Terblanche.Theeffectsofexhaustiveexerciseontheactivity levelsofcatalaseinVgI*iOHStissuesofmaleandfemalerats.Cell biologyinternational,1999,23(11):749—753.傅静波,刘洪珍,少年在亚极量,极量负荷运动下血中MDA, GSH,SOD和CA T的变化[J].中国体育科技,2000,36(8):34—38.王梅.运动与自由基代谢[J].中国l临床康复,2002,6(3):408—4O9.。
Novel Strategy for Selection of Monoclonal Antibodies
Novel Strategy for Selection of Monoclonal Antibodies Against Highly Conserved Antigens:Phage Library Panning Against Ephrin-B2Displayed on YeastXiaoling Gu1.,Yogindra Vedvyas1.,Xiaoyue Chen1.,Tanwi Kaushik1,Chang-Il Hwang2,Xuebo Hu1, Alexander Y.Nikitin2,Moonsoo M.Jin1*1Department of Biomedical Engineering,Cornell University,Ithaca,New York,United States of America,2Department of Biomedical Sciences,Cornell University,Ithaca, New York,United States of AmericaAbstractEphrin-B2is predominately expressed in endothelium of arterial origin,involved in developmental angiogenesis and neovasculature formation through its interaction with EphB4.Despite its importance in physiology and pathological conditions,it has been challenging to produce monoclonal antibodies against ephrin-B2due to its high conservation in sequence throughout human and ing a novel approach for antibody selection by panning a phage library of human antibody against antigens displayed in yeast,we have isolated high affinity antibodies against ephrin-B2.The function of one high affinity binder(named as‘EC8’)was manifested in its ability to inhibit ephrin-B2interaction with EphB4, to cross-react with murine ephrin-B2,and to induce internalization into ephrin-B2expressing cells.EC8was also compatible with immunoprecipitation and detection of ephrin-B2expression in the tissue after standard chemical fixation procedure.Consistent with previous reports on ephrin-B2induction in some epithelial tumors and tumor-associated vasculatures,EC8 specifically detected ephrin-B2in tumors as well as the vasculature within and outside of the tumors.We envision that monoclonal antibody developed in this study may be used as a reagent to probe ephrin-B2distribution in normal as well as in pathological conditions and to antagonize ephrin-B2interaction with EphB4for basic science and therapeutic applications.Citation:Gu X,Vedvyas Y,Chen X,Kaushik T,Hwang C-I,et al.(2012)Novel Strategy for Selection of Monoclonal Antibodies Against Highly Conserved Antigens: Phage Library Panning Against Ephrin-B2Displayed on Yeast.PLoS ONE7(1):e30680.doi:10.1371/journal.pone.0030680Editor:Wei-Chun Chin,University of California Merced,United States of AmericaReceived June29,2011;Accepted December21,2011;Published January23,2012Copyright:ß2012Gu et al.This is an open-access article distributed under the terms of the Creative Commons Attribution License,which permits unrestricted use,distribution,and reproduction in any medium,provided the original author and source are credited.Funding:This work was supported by National Institutes of Health Grant AI179532(MMJ),GM090320(MMJ),CA96823(AYN),CA112354(AYN)and Northeast Biodefense Center U54-AI057158(Lipkin)(/)(/).The funders had no role in study design,data collection and analysis,decision to publish,or preparation of the manuscript.Competing Interests:The authors have declared that no competing interests exist.*E-mail:mj227@.These authors contributed equally to this work.IntroductionThe erythropoietin-producing hepatocellular(Eph)receptors and their ligands,ephrins comprise the largest subfamily of receptor tyrosine kinases(RTK),playing an important role in physiology such as embryogenesis,organ development,and angiogenesis as well as implicated in several types of cancers[1]. Among different classes of ephrins,ephrin-B2is primarily expressed in arterial endothelial cells and neovasculature,forming a bidirectional signal with its cognate receptor EphB4,which is mainly expressed in venous endothelial cell[2,3].The importance of such interaction in a developmental process has been demonstrated by impaired angiogenesis and ultimately embryonic lethality in mice due to homozygous mutation of ephrin-B2or EphB4[3,4,5,6].The role of EphB4and ephrin-B2also extends to tumor growth and angiogenesis[1,7].Inhibition of their interaction by EphB4antibody or extracellular fragment of EphB4can inhibit tumor angiogenesis and tumor growth [8,9,10].Ephrin-B2is involved in vascular endothelial growth factor(VEGF)signaling,through the internalization of VEGF receptor in all endothelial cell types during physiological and pathological angiogenesis[11,12,13],and could be upregulated in VEGF-treated endothelial cells[5,6].Expression of ephrin-B2 along with EphB4was found to be higher in many tumors including colorectal,breast,ovarian,and lung,serving as a poor prognostic marker[14,15,16,17,18].Despite the importance of ephrin-B2in physiology and pathological conditions,there are no widely available monoclonal antibodies against ephrin-B2,likely attributed to the fact that immume system in rodents prevents responses to self antigen or to highly conserved human antigens.To overcome the problem with generating antibodies against highly conserved antigens,mice with impaired immune tolerance(B/W)have been exploited [19,20];however,concerns remain on this alternative approach due to the observations of multi-specificity and low-affinity on auto-antibodies developed from autoimmune mice[20].In order to generate antibodies against highly conserved ephrin-B2,we used phage display of single chain human antibody and screened them against ephrin-B2expressed in yeast.From our previous work[21],we found that phage panning against antigens displayed in yeast is highly efficient in rapid enrichment of specific phage clones,obviating the need to produce soluble antigens as well as ensuring native conformation.With newly developed monoclonal antibody,we found that tumors of colon,breast,ovary,and lung upregulated ephrin-B2compared to respective normal tissues.Antibody staining was also observed in the neovasculature within the tumor,corresponding to new vessel sprouts.Our antibody also exhibited properties such as its ability to cross-react with murine ephrin-B2,to inhibit EphB4binding,and to be internalized into cells after binding to ephrin-B2.We anticipate that antibodies developed in this study will be useful in probing ephrin-B2distribution in normal and disease processes,and in antagonizing the interaction between ephrin-B2and EphB4for scientific and therapeutic applications.ResultsNovel strategy of selecting antibodies against ephrin-B2We have previously shown that phage library of human antibody can be directly panned against antigens expressed in yeast (Fig.1A)with great efficiency in selection of high affinity monoclonal antibodies [21].Surface expression of ectodomain of ephrin-B2on yeast cell surface was first validated by antibody binding to Myc tag,which was placed at the C-terminal of ephrin-B2,as well as the binding of EphB4,a physiological receptor of ephrin-B2(Fig.1A&B).Subtractive panning of a phage library of human single chain fragment variable fragment (scFv),consisting of depletion against yeast expressing irrelevant antigens followed by positive selection against ephrin-B2,resulted in a progressive increase in the percentage of phage clones bound to ephrin-B2(Fig.1B).A total of 96phage clones were selected from the third round pool and tested individually for binding to ephrin-B2usingflow cytometry.This resulted in 85clones with positive binding (data not shown).Out of these 85clones,10high-affinity phage clones were then sequenced,which identified three unique clones (designated as scFv-EA6,scFv-EB1and scFv-EC8).Two best binders,scFv-EB1and scFv-EC8were chosen for production in bacteria and purified by nickel-nitrilotriacetic acid (Ni-NTA)column,followed by gel filtration chromatography,which resulted in one distinct band around 35kDa in SDS-PAGE (Fig.1C).Soluble scFv-EB1and scFv-EC8not only retained binding to yeast but also showed specific binding to ephrin-B2expressed in mammalian cells,judging from the detection of basal expression in 293T and enhanced binding after transient expression of full-length ephrin-B2in 293T (Fig.1D).scFv-EA6,scFv-EB1and scFv-EC8differed mainly within the complementarity determining regions (Fig.1E).Overall,scFv-EC8showed highest binding affinity to ephrin-B2,and was chosen for further studies.Characterization of single-chain antibody fused to Fc domainAlthough scFv-EC8was fully functional in binding to ephrin-B2,for future in vivo applications and many standard assays relying on the presence of immunoglobulin Fc region,scFv fusion to Fc was constructed in pcDNA3.1and produced in mammalian cells (Fig.2A).Under the reducing condition,the Fc fusion of scFV-EC8migrated around 64kDa,consistent with its nominal molecular weight.scFv-EC8fusion to Fc (designated as EC8)was fully functional,retaining specific binding to ephrin-B2expressed in yeast and in 293T (Fig.2B)with higher levelofFigure 1.Selection,validation,and sequence of ephrin-B2-specific human single-chain antibodies.(A)A schematic diagram of phage panning against antigens expressed in yeast display system [34].(B)Immunofluorescence flow cytometry measurements of protein and phage binding to yeast cells.Surface-displayed ephrin-B2was detected by the binding of anti-Myc antibody (‘Myc’)as well as recombinant human EphB4-Fc (‘EphB4’)to yeast cells (top panel).Progressive enrichment of phage clones from first three rounds of panning (denoted as ‘1st’,‘2nd’and ‘3rd’)was detected by antibody against His tag (bottom panel).Histograms drawn in shaded area and solid lines indicate antibody binding to uninduced and induced yeast cells,respectively.The percentage of phage clones with positive binding is indicated.(C)SDS-PAGE of scFv-EB1(lane ‘1’)and scFv-EC8(lane ‘2’).(D)Ephrin-B2specific scFv binding to irrelevant yeast cells,yeast cells with expression of ephrin-B2ectodomain,293T cells,and 293T cells with transient expression of full-length ephrin-B2.Shown are the histograms of cells labeled with secondary antibody with (solid line)and without (shaded area)ephrin-B2specific scFv as primary antibody.(E)Sequence alignment of scFv-EA6,scFv-EB1,and plementarity determining regions (CDR),the beginning of immunoglobulin variable heavy (VH)and variable light (VL)chain domains,and the linker connecting VH and VL are noted.*indicates amino acids differ between scFvs.doi:10.1371/journal.pone.0030680.g001binding compared with the levels seen with scFv-EC8(Fig.1D).EC8also exhibited comparable binding to murine ephrin-B2expressed in transformed murine ovarian cells [22](Fig.2B),an anticipated result due to the fact that murine ephrin-B2differed by only three residues from human ephrin-B2expressed in yeast (Thr-22to Gly-165)for phage screening.The binding affinity (equilibrium dissociation constant,K D )of EC8to ephrin-B2was around 3.2nM,based on the fluorescence measurement using ephrin-B2-expressing 293T cells labeled in serial dilutions of EC8(Fig.2C).The increase in affinity of EC8to ephrin-B2was due to the dimerization effect of scFv,commonly noted as bivalency or avidity effect.EC8was conformation-specific against ephrin-B2,indicated from significant loss of binding to ephrin-B2expressing yeast cells when ephrin-B2was partially denatured by incubating cells eitherin guanidine hydrochloride at 6M or in elevated temperature (Fig.2D).The reduction in the level of EC8binding to ephrin-B2was not due to a change in surface expression as antibody binding to Myc tag was invariant.The property of EC8to recognize conformation-specific epitope was also corroborated by its inability to stain ephrin-B2in western blot (data not shown).We then tested if EC8would specifically pull down ephrin-B2from detergent-solubilized 293T cell lysates.Conformation-specificity of mono-clonal antibody (mAb)EC8was also confirmed with the detection of one distinct band of ,45kDa in size from the lysates only after precipitation with EC8,stained by polyclonal antibody against ephrin-B2(Fig.2E).Due to high sequence homology among some members of ephrin family,polyclonal antibodies against ephrin-B2often crossreact with other ephrins like ephrin-B1and ephrin-A5,which share sequence identity at 43%and 41%withephrin-B2,Figure 2.Conversion of scFv-EC8as a fusion to immunoglobulin Fc and functional test.(A)SDS-PAGE images of EC8resolved under reducing (R)and non-reducing (NR)conditions.(B)EC8(solid line)binding to yeast cells,293T with stable expression of ephrin-B2,and murine ovarian epithelium.The binding of isotype control is shown in shaded area.(C)Flow cytometry measurements of EC8binding to 293T cells are shown in filled squares.First order Langmuir adsorption model was used to fit the data to estimate equilibrium dissociation constant (K D ).(D)Conformation speficifity of EC8against eprhin-B2was examined by flow cytometry with (‘+’)or without (‘2’)incubating cells either in 6M guanidine hydrocholoride (‘GnHCl’)for 20min or in elevated temperature at 80u C (‘Heat’)for 10min.(E)Western blot image of immunoprecipitated ephrin-B2from 293T cells with (‘+’)or without (‘2’)EC8antibody,detected by rabbit ephrin-B2polyclonal antibody.(F)Flow cytometry measurements of EC8binding to ephrin-B1and ephrin-A5displayed on beling of uninduced yeast cells is shown in shaded histograms.(G&H)Competition assay.Relative binding of EphB4(100nM)to yeast cells expressing ephrin-B2,preincubated with varying concentrations of EC8,was measured by flow cytometry.Affinity purified human IgG was included as isotype control.n =3independent measurements.(I)Confocal microscopic images of surface-bound EC8and internalized ones before and after membrane permeabilization of 293T cells.Scale bar =10m m.doi:10.1371/journal.pone.0030680.g002respectively.While EphB2showed comparable binding to all three ephrins tested,EC8was found specific to ephrin-B2with little binding to ephrin-B1and ephrin-A5(Fig.2F).mAb EC8blocked ephrin-B2interaction with EphB4and was internalized by ephrin-B2ligationAfter confirming specific binding of EC8to ephrin-B2,we examined if EC8was able to block ephrin-B2interaction with its cognate receptor,EphB4.This would potentially be useful in blocking bidirectional signals triggered by ephrin-B2and EphB4interaction,which is important for normal physiology as well as in disease progression.In comparison to human immunoglobulin G (IgG)as isotype control,increasing concentration of EC8added to yeast cells expressing eprhin-B2led to a gradual decrease in the binding of EphB4(used at 100nM)to ephrin-B2,close to complete inhibition seen at 250nM of EC8(Fig.2G&H).We detected the distribution of EC8in 293T after labeling under fluorescence microscope,and observed that ephrin-B2ligation by EC8triggered cells to internalize the antibody.In order to differentiate surface-bound vs.intracellular pool of EC8,confocal microscopy was used to image cells prior to and after membrane permeabilization,which visualized distinct intracellular staining of EC8(Fig.2I).EC8detection of ephrin-B2expression in tumor tissues and tumor-associated vasculatureUpregulation of ephrin-B2/EphB4has been observed in many tumors,including ovary,colon,breast,and glioma,with a strong correlation with poor prognosis [14,15,16,17,18,23,24].With two widely used colon cancer cell lines,COLO205and HCT116,we found upregulation of ephrin-B2by flow cytometry using EC8(Fig.3A).Chinese hamster ovarian (CHO)cells with no ephrin-B2expression were included as a negative control.The relative levels of eprhin-B2between different cell lines were further confirmed by RT-PCR,with 293T cells stably expressing ephrin-B2as a positive control (Fig.3B).Since not all conformation-specific antibodies are compatible with immunohistology after a standard procedure for tissue fixation,we examined if EC8can be used to probe eprhin-B2expression in the tissue.When colon tumor tissues were immunostained after tumor growth in mice and harvest,EC8not only delineated human tumor xenograft with high ephrin-B2expression,but also identified the vasculature within the tumor due to the cross-reactivity of EC8with both human and murine ephrin-B2(Fig.3C).EC8staining of ephrin-B2clearly differen-tiated tumor cells (marked with arrowhead)from the murine stroma (marked with arrow)(Fig.3C).EC8detection of the upregulation of ephrin-B2in diverse human tumors of epithelial originWe further examined if EC8could be applied to detect ephrin-B2expression in other types of tumor directly collected from human patients.Among several epithelium-originated cancers,ranging from ovarian,lung,prostate,breast to colon,high level expression of ephrin-B2was all found by immunostaining (Fig.4A&B).In comparison to normal tissues or tumor stroma showing no or only baseline ephrin-B2staining,malignant tumor cells characterized by their irregular cell shape (e.g.colon and lung)and aberrantly enlarged (e.g.colon,lung and prostate)or dense (e.g.breast)nucleoli had distinctively higher ephrin-B2staining.Dual staining on human colon cancer sample with both anti-CD31antibody and EC8revealed some of the vasculatures that were co-stained,indicative of EC8detecting tumor-associated vasculature (Fig.4C).DiscussionEphrin-B2is preferentially expressed in arterial endothelium and smooth muscle cells,as well as neovasculature within the tumor.Expression of ephrin-B2is modulated by VEGF,smooth muscle cell contact,and stress [25,26,27].Ephrin-B2has also shown to be upregulated in many cancers,including colon [15],uterine [16],ovarian [17]and esophageal cancers [18].Despite the importance of the role of ephrin-B2in physiology and disease,up until now monoclonal antibody specific to ephrin-B2has not been widely available.This may be attributed to the fact that human ephrin-B2is highly homologous to those of other mammals including rodents,presenting a challenge to isolating high affinity antibody from immunization and hybridoma technique.Limited in vivo alternatives for making antibodies against highly conserved antigens,including using mice with impaired immune response [19,20],have been reported,yet the concerns remain on the multi-specificity and low-affinity of auto-antibodies[20].Figure 3.Detection of ephrin-B2expression in human cancer cell lines and tumor xenograft in mice.(A)Flow cytometry measurements of EC8binding to COLO205and HCT116cells (solid line)in comparison to the isotype control (shaded area).CHO cells with no ephrin-B2expression were also included for comparison.(B)RT-PCR detection of ephrin-B2expression in different cell lines.(C)Immunostaining of ephrin-B2on human colon cancer xenografted in mice.Control denotes immunostaining without EC8as a primary antibody.Tumor and stromal cells were indicated with arrowhead and arrow,respectively.Circle indicates murine endothelium stained with EC8.Scale bar =20m m.doi:10.1371/journal.pone.0030680.g003Here we report the isolation of monoclonal antibody against ephrin-B2,which was selected from a phage library of human single chain antibody.Rather than panning phage clones against soluble antigens,we used yeast cells expressing antigens to pull down reactive phage clones,which was found to be highly efficient in rapidly enriching specific phage library.Given the library diversity (108)and an enrichment factor of 102–103per each round of our screening strategy [21],we were able to observe specific phage clones reactive to ephrin-B2as early as after two rounds of sorting.As antibody selection is based on monomeric interaction between antigen-antibody,after conversion into a dimer by fusion to IgG Fc,the affinity (K D =3.2nM)of ephrin-B2antibody (EC8)was comparable to those of high affinity monoclonal antibodies produced from pared to many polyclonal antibodies generated from peptide fragments by immunization,EC8selected against ephrin-B2displayed in native conformation on yeast surface was found to be conformation-specific and discriminate ephrin-B2from other ephrins with high homology.Antibodies against EphB4were found to inhibit tumor growth and angiogenesis,some of which are being investigated for anti-cancer therapy in preclinical studies [9,10].Eph receptor antibodies that were conjugated to small molecule drugs caused internalization of drugs and inhibition of tumor growth in vivo [28,29].Soluble extracellular domain of EphB4targeting ephrin-B2has been used in inhibiting angiogenesis and tumor growth in vivo [8].We have found that mAb EC8potently antagonized ephrin-B2binding to EphB4,which would block forward and reverse signaling by EphB4and ephrin-B2interaction.Similar to the observation of EphB4upregulation in some tumors,when human tissue array was probed with mAb EC8,ephrin-B2was found to be also overexpressed intumors in lung,breast,ovary,colon,and prostate over respective normal tissue.Consistent with the previous observation of ephrin-B2expression in tumor-associated vasculature,EC8delineated ephrin-B2expression in newly formed vessels within the tumor.Upregulation of ephrin-B2was also found in colorectal cancer cell lines,COLO205and HT108both in cell culture and as a tumor xenograft in mice.Notably,due to the cross-reactive nature of antibody with murine ephrin-B2,mAb EC8also identified tumor-associated vasculature,simultaneously detecting ephrin-B2in human tumor as well as ephrin-B2in murine host.Neovasculatures in adults sprouting from arterial vessels and capillaries,whether caused by VEGF-signaling,tissue injury,or tumor growth,were found to express ephrin-B2.It is unknown how ephrin-B2upregulation in some of the tumors of epithelium origin would perturb the balance between ephrin-B2and Eph4expressed in arterial and venous vessels,respectively,and contribute to the tumor growth and metastasis.Given the observation that overexpression of ephrin-B2in some tumors is correlated with poor prognosis [1,16],it will be an interesting question if the role of ephrin-B2together with EphB receptors in some tumor is associated with the promotion of the vasculature growth and the adenoma-carcinoma transition,facilitating tumor metastasis.We propose that high affinity and antagonist antibodies such as EC8would provide a valuable tool for examining the role of ephrin-B2expression on tumor angiogenesis and migration.Materials and MethodsSelection and expression of ephrin-B2-specific scFvsA part of human ephrin-B2ectodomain (Thr-22to Gly-165)was cloned into yeast surface display vector,CAga2(amodifiedFigure 4.Detection of ephrin-B2expression in human tissue arrays.(A&B)Immunostaining of ephrin-B2expression in human tumor tissue arrays using EC8.Control denotes immunostaining without EC8as a primary antibody.Tumor and stromal cells were indicated with arrowhead and arrow,respectively.Scale bar =20m m.PAC =Papillary Adenocarcinoma;AC =Adenocarcinoma;BR =Bronchus;AL =Alveoli;SC =Squamous Cell Carcinoma;SAC =Serous Adenocarcinoma.IDC =Nonspecific Infiltrating Duct Carcinoma.(C)Immunofluorescence staining on human colon tumor tissue demonstrating that EC8(red)detects ephrin-B2expressions in both cancer cells and tumor-associated vasculature (green).Blow up views of the two areas indicated with dashed box are shown in the right panel.Scale bar =100m m.doi:10.1371/journal.pone.0030680.g004version of PCTCON[30]),and transformed into yeast strain EBY100by EZ-transformation kit(Zymo Research).Yeast culture and protein induction were performed as previously described [30].Proteins displayed on yeast contain ephrin-B2ectodomain, Myc tag,and Aga2from N-to C-terminal.Surface expression of ephrin-B2in yeast was measured by immunofluorescence flow cytometry using mouse anti-Myc antibody(9E10,Santa Cruz Biotechnology)followed by goat phycoerythrin-conjugated anti-mouse antibody(Santa Cruz Biotechnology),as well as by recombinant human EphB4-Fc chimera(Biomiga)followed by goat phycoerythrin-conjugated anti-human antibody(Santa Cruz Biotechnology).A phage library of human single chain variable fragment(scFv)antibody with108diversity(Tomlinson I+J, Source BioScience)was panned against ephrin-B2expressing-yeast cells,following a procedure previously described[21].Briefly, 261013phage clones were first incubated with phosphate buffered saline(PBS)containing2%nonfat dry milk(Carnation)for30min at room temperature(RT),to which26107yeast cells expressing unrelated protein(Zif268)was added for depletion of non-specific phage binders.The mixture of phage and yeast cells were then incubated for1h at RT with agitation.Non-binding phage clones in the supernatant were removed after centrifugation to pellet yeast cells,which were subsequently washed five times with PBS/ 0.05%Tween20.Then phage particles were eluted from yeast cells with trypsin and used to infect Escherichia coli(TG1)to amplify enriched phage library for the next round of selection.After three rounds of selection,,200TG1clones were picked to produce individual phage clones.The binding of phage clones to ephrin-B2 expressing yeast cells was measured by immunofluorescence flow cytometry using anti-His tag antibody(Sigma-Aldrich)followed by goat phycoerythrin-conjugated anti-mouse antibody(Santa Cruz Biotechnology).Expression of scFvIndividual phage clones with high affinity binding to ephrin-B2 were sequenced,and selected scFv antibodies were solubly expressed from bacteria HB2151(Clontech).Transformed HB2151cells were grown at OD600=0.4,to which1mM isopropyl b-D-1-thiogalactopyranoside was added.Cells were induced to express protein at25u C by culturing for16h with shaking at250rpm.After induction,cells were spun down, resuspended in binding buffer(50mM sodium phosphate,pH8.0, 300mM sodium chloride,and10mM imidazole),sonicated to break the cell wall,and were spun at10,000g for15min to remove cell debris.Proteins in the supernatant were purified with Ni-NTA column followed by gel filtration chromatography using Superdex75column connected to AKTA Purifier(GE Health-care).The purity and the size of proteins were confirmed by sodium dodecyl sulfate(SDS)polyacrylamide gel electrophoresis (PAGE).Cell cultureChinese hamster ovary(CHO)cells[30]were maintained in Ham’s F12medium(Invitrogen)supplemented with2mM L-glutamine and5%fetal bovine serum(FBS).Colorectal adeno-carcinoma COLO205[31]were cultured in RPMI1640medium supplemented with2mM L-glutamine,10%FBS and1% Penicillin-Streptomycin.HCT116colon cancer cell line[32]was grown in McCoy’s5A Medium(Invitrogen)supplemented with 10%FBS.Human embryonic kidney(HEK)293T cells[30]were maintained in advanced DMEM supplemented with10%FBS, 2mM L-glutamine,20m g/mL hygromycin and1%Penicillin-Streptomycin.All cell cultures were maintained at37u C in a humidified5%CO2atmosphere.293T cells stably expressing ephrin-B2were established by transfection of cells with pcDNA3.1 (Invitrogen)containing full-length ephrin-B2with200m g/ml of hygromycin for selection.Immunofluorescence flow cytometryProtein expression on yeast cell surface was analyzed by flow cytometry as described[33].Briefly,yeast cells were incubated with primary antibodies(10m g/ml)in200m l of labeling buffer (PBS/0.5%bovine serum albumin)for1h with shaking at30u C. Cells were then washed and incubated with secondary antibodies in200m l of labeling buffer for1h at RT.After washing,cells were resuspended in200m l of labeling buffer and subjected to flow cytometry.The expression of ephrin-B2in mammalian cells was detected by incubating cells with ephrin-B2antibody for1h at 4u C,followed by Alexa Fluor488(AF488)-conjugated goat anti-human secondary antibody(Invitrogen).Flow cytometry was performed on a FACSCalibur(BD Biosciences)and analyzed with CellQuest software(BD Biosciences).Conversion of scFv into scFv-FcIn order to fuse scFv into immunoglobulin G(IgG)constant region(Fc)including a hinge sequence,scFv sequence followed by IgG1Fc was cloned into pcDNA3.1.scFv-Fc fusion protein was expressed in293T cells and purified with Protein A beads (Thermo Scientific).Conformation specificity and selectivity of EC8against ephrin-B2Yeast cells expressing ephrin-B2were incubated either in 50mM Tris buffer(pH8.0)containing6M guanidine hydro-chloride for20min at room temperature,or in labeling buffer (PBS/0.5%bovine serum albumin)heated to80u C for10min,to denature ephrin-B2.EC8or EphB4-Fc binding to yeast cells after denaturation of ephrin-B2was then measured by flow cytometry. To examine crossreactivity of EC8to other ephrins,human ephrin-B1(Leu-24to Gly-165)and ephrin-A5(Pro-22to Gly-169) ectodomains were cloned and displayed on yeast surface. Immunofluorescence flow cytometry was conducted with mouse anti-Myc antibody(9E10,Santa Cruz Biotechnology),recombi-nant human EphB2/Fc chimera(R&D Systems),and EC8 followed by respective secondary antibodies as previously described.Competition assayYeast cells expressing ephrin-B2were incubated with varying concentrations of mAb EC8or affinity(protein A column,Pierce) purified human IgG for20min at30u C,to which recombinant human EphB4containing His-tag at C-terminal(R&D Systems) was added at100nM and incubated for20min at30u C.The binding of EphB4to yeast was detected by flow cytometry using anti-His tag antibody,followed by phycoerythrin-conjugated goat anti-mouse antibody.Immunoprecipitation of ephrin-B2by mAb EC8293T cells with stable expression of ephrin-B2were incubated in lysis buffer(20mM Tris-HCl,pH8.0,137mM NaCl,10% glycerol,1%Triton X-100,2mM ethylenediaminetetraacetic acid (EDTA),protease inhibitor cocktail(Sigma))for30min on ice. Cell debris were removed by centrifugation for20min at 14,000g.Total protein lysate was precleared by Protein A beads for1h at4u C.After centrifugation,supernatants were collected and incubated with10m g/ml EC8for2h at4u C,followed by incubation with Protein A beads overnight at4u C.Immunopre-。
二氧化碳共聚物
Carbon dioxide resin
Carbon dioxide resin material is a kind of working on a new type of synthetic material, monomer with carbon dioxide as raw materials in the catalyst (double metal complexing PBM type, etc.), the activated to a higher level, and epoxide copolymerization reaction, generate aliphatic polycarbonate, through post-processing, get carbon resin material.Add other reactants in polymerization, can get different chemical structure of resin carbon dioxide.There are many kinds of carbon dioxide copolymer aliphatic polycarbonate, but the most commercially use value is the copolymerization of carbon dioxide with propylene oxide product of propylene carbonate (或称聚甲基乙撑碳酸酯; Polypropylene carbonate ,简称PPC)。
• Air Products and Chemicals Inc., in 1994, the existing sale of carbon dioxide copolymer (the number average molecular weight of 5000), the design of the annual output of 20000 tons, sells for about $7000 / tons, mainly sold in the United States and Japan, for the cling film at low temperature of fresh beef and mutton.Japan also has formed annual production of 3000-4000 tons of production capacity, priced at $10000 $30000 per ton. • guangzhou institute of chemical load bimetallic catalyst research made a very meaningful work, recently in load type organic carboxylic acid zinc catalyst properties of polymer, and has made great progress. • Changchun institute of applied chemistry in recent years has carried out the research of rare earth composite catalyst fixed
选矿专业英语词汇
专业英语词汇共 12 页 第 1 页矿物加工工艺学(浮选部分)英文词汇floatation 浮选froth flotation 泡沫浮选 direct flotation 正浮选 reverse flotation 反浮选fineness of grinding 磨矿细度 fractionation 分级mineral wettability 矿物润湿性 mineral flotability 矿物的可浮性 equilibrium contact angle 平衡接触角 three phase interface 三相界面hydrophobicity of mineral 矿物的疏水性 hydrophilicity of mineral 矿物的亲水性 foam adhesion 泡沫附着 ionic lattice 离子晶格 covalence lattice 共价晶格surface inhomogeneity 表面的不均匀性 oxidation and dissolution 氧化与溶解 oxidizing agent 氧化剂 reduction agent 还原剂surface modification of mineral 矿物的表面改性 electric double layer 双电层 ionization 电离 adsorption 吸附electrokinetic potential 电动电位 point of zero charge 零电点 isoelectric point 等电点 collecting agent 捕收剂semi micelle adsorption 半胶束吸附 exchange adsorption 交换吸附 competitive adsorption 竞争吸附 specific adsorption 特性吸附 modifying agent 调整剂 depressant 抑制剂activating agent 活化剂 foaming agent 起泡剂hydrophilic group 亲水基团 liberation degree 解离度 polar group 极性基团nonpolar group 非极性基团 sulphide ore 硫化矿物 oxidized mineral 氧化矿物 xanthate 黄药 hydrolysis 水解medicamentous selectivity 药剂的选择性catchment action 捕收作用electrochemical action 电化学作用 pyrite 黄铁矿 calcite 方解石alkyl radical 烃基含氧酸 organic amine 有机胺类carboxylate surfactant 羧酸盐 kerosene 煤油amphoteric collector 两性两捕收剂 alkyl radical sulfonate 烃基磺酸盐 complex 络合物pH modifying agent pH 调整剂 long-chain molecule 长链分子 chalcopyrite 黄铜矿 galena 方铅矿 blende 闪锌矿oxidized ore 氧化矿 flocculant 絮凝剂non-hydronium flocculant 非离子型絮凝剂 desorption 解吸 air bladder 气泡 solubility 溶解度specific surface area 比表面积 mineral resources 矿源three phase air bladder 三相气泡ore magma electric potential 矿浆电位 mixed potential model 混合电位模型freedom hydrocarbon diversification 自由烃变化 electrostatic pull 静电引力 intermolecular force 分子间力 goethite 针铁矿semi micelle adsorption 半胶束吸附 concentration of solution 溶液浓度 flotation machine 浮选机 oxygenation 充气作用 recovery 回收率concentrate grade 精矿品位 handling capacity 处理能力 air bladder collision 气泡碰撞 flotation column 浮选柱ore concentration dressing 富集作用 floatation process 浮选工艺 floatation speed 浮选速率 flotation circuit 浮选流程共 12 页 第 2 页矿物加工工艺学(重选部分)英文词汇(1) gravity concentration 重力选矿 (2) Abkhazite 透闪石棉 (3) Amiantus 石棉 (4) acceptance operation 矿石预选 (5) Acclivity 斜面 (6) airborne dust 大气浮尘 (7) air conveying 风力输送 (8) amplitude of vibration 振幅 (9) ancillary mineral 伴生矿物 (10) a pparent viscosity 视粘度 (11) a rtificial bedding 人工床层 (12) a ttle 废石 (13) a verage grain diameter 平均粒径 (14) a xial motion 轴向运动 (15) b ackwash water 冲洗水 (16) b ackwater 筛下水 (17) b arite 菱镁蛇纹岩 (18) b arren rock 脉石 (19) b each ore 砂矿 (20) b ed separation 分层 (21) b evel angle 倾斜角 (22) b uddle 淘洗盘 (23) b uddle jig 动筛跳汰机 (24) b uoyancy 浮力 (25) b uoyant weight 悬浮重量 (26) C aplastometer 粘度计 (27) C entipoises 厘泊 (28) C entrifugal field 离心力场 (29) C entrifugal jig 离心跳汰机 (30) C ircular 圆形跳汰机 (31) C entrifuge 离心机 (32) C lassification efficiency 分级效率 (33) C lassifier 分级机 (34) C lassifier overflow 分级机溢流 (35) C lassifier sand 分级机返砂 (36) C lose sizing 窄级分级 (37) C laster of particles 颗粒群 (38) C oarse feed 粗粒给料 (39) C yclone 水力旋流器 (40) C assiterite 锡石 (41) D ilated 松散床层 (42) d imensionless parameter 无因次参数 (43) d uplex table 双层摇床 (44) d iaphragm jig 隔膜跳汰机 (45) d windles out 尖灭 (46) f ilm concentration 流膜选矿 (47) f inal velocity 末速度 (48) f ree settling particle 自由沉降颗粒 (49) f ree settling ratio 自由沉降比 (50) g ravity concentrate 重选精矿 (51) g ravity tailings 重选尾矿 (52) g alena 方铅矿 (53) i ron ore pellet 铁矿球团 (54) j ig cycle 跳汰周期 (55) h eavy liquid 重液 (56) h eavy-media separator 重介质分选 (57) h eavy-media suspension 重介质悬浮液 (58) h ydraulic analysis 水力分析 (59) h igh-weir spiral classifier 高堰式螺旋分级机 (60) h indered settling 干涉沉降 (61) H MS-flotation method 重介质浮选联合分选 (62) H ydrocyclone 水力旋流器 (63) L aundering 溜槽选矿 (64) l ow- weir spiral classier 低堰式螺旋分级机 (65) m edium recovery screen 介质回收筛 (66) m eerschaum 海泡石 (67) m enachanite 钛铁砂 (68) o uter vortex 外螺旋线 (69) p article diameter 颗粒直径 (70) p article shape 颗粒形状共12 页第3 页专业英语词汇矿物加工工艺学(磁电选矿部分)英文词汇Mineral Processing Technology 矿物加工工艺学Principle of magnetism process 磁选原理Magnetic force 磁力Ratio magnetic force 比磁力Compete force 竞争力Mineral magnetism 矿物的磁性Atomic magnetism moment 原子磁矩Molecular magnetism moment 分子磁矩Magnetization & magnetic field 磁化和磁化磁场Magnetization intensity 磁化强度Ratio susceptibility 比磁化系数Diamagnetism 逆磁性Paramagnetism 顺磁性Ferromagnetism 铁磁性Magnetic domain 磁畴Revers ferromagnetism 反铁磁性Subferromagnetism 亚铁磁性Coercive force 矫顽力Remanence 剩磁Magnetization roasting 磁化焙烧Deoxidization roasting 还原焙烧Midlle roasting 中性焙烧Oxidation roasting 氧化焙烧Siderite 菱铁矿Hematite 赤铁矿Magnetite 磁铁矿Unhydrophite magnetization 疏水磁化Magnetic process equipment 磁选设备Feebleness magnetic separation machine 弱磁场磁选机Dry magnetic separation machine 干式磁选机Wet feebleness magnetic separation machine 湿式弱磁场磁选机High magnetic separation machine 强磁场磁选机High grads magnetic sparation machine 高梯度磁选机Supercondduct magnetic separation 超导电选Concentrator 选矿机Electrity process 电选Electrity concentrator 电选机Static separation 静电选矿Air-ionization separation 电晕分选Friction electric separation 摩擦电选Magnetic process practice 磁选实践Nonmetal ore 非金属矿Diamond process 金刚石选矿Heavy medium reclaim 重介质回收共12 页第4 页专业英语词汇Primary concentrate 粗精矿Graphite gangue 石墨尾矿Kaolin magnetic process 高岭土磁选Block metal ore 黑色金属矿石Manganese ore magnetic process 锰矿石磁选Coloured metal & rare metal 有色金属和稀有金属Ilmenite 钛铁矿Rutile 金红石Zircon 锆英石Electric process practice 电选实践Tungstate 钨酸盐cassiterite 锡石hematite . 赤铁矿gangue 脉石,废石,矸石magnet .磁铁,磁体,磁石conductor mineral 导体矿物silicate 硅酸盐diatomite 硅藻土hysteresis 磁滞现象magnetic core . 磁铁芯winding 绕组,线圈medium 介质electrophoresis 电泳screening 筛分magnetic field 磁场flux 磁通量ferromagnet 铁磁物质ferromagnetism 铁磁性reunite 团聚magnetic system 磁系magnetic agitate 磁搅动permanent magnet 永久磁铁solenoid magnet 螺管式磁铁pyrite .黄铁矿,硫铁矿limonite 褐铁矿reluctivity 磁阻率conduct 传导induce .诱导,感应,归纳astrict 束缚charge 电荷electric field .电场interfacial 界面的,面间的magnetism 吸引力electrode 电极,电焊条,电极Strontium & iron oxid 锶铁氧体Periodic magnetic field 交变磁场共12 页第5 页专业英语词汇共 12 页 第 6 页Pulsant magnetic field 脉动磁场 Saturation 饱和 stainless steel material 不锈钢材料 polar distance 极距 mica 云母 quarte 石英 stimulate magnetism 激磁 magnetism circuit 磁路 magnetic line of force 磁力线 commutate quality 整流性Flatation reagent professional wordsAbsorption 吸收Absorption band 吸收光谱带 Abstract 抽出,提取 Abundance 丰富,丰度 Accelerant 促进剂 Acceptance 验收,接收 Accumulate 积累,聚集 Accuracy 准确度 Acctate 醋酸盐 Acctamide 乙酰胺 Acid 酸,酸的Acid anion 酸性阴离子 Acidation 酸化Acid depression 加酸抑制 Acid hydrolysis 加酸水解 Acintol 妥尔油制品 Acrylic amide 丙烯酰胺 Activate 活化Activated adsorption 活性吸附 Activated molecule 活化分子 Activated effect 活化作用 Activator 活化剂,活性剂 Acto 精制石油磺酸钠 Acylamide 酰胺 Addition 加添Adhere 粘附,附着Adhesion coefficient 粘着系数 Adhesive 粘合剂Adhesive tension 胶结张力 界面吸引力 Adion 吸附离子 Adsorbate 吸附物 Adsorbent 吸附剂Adsorption isotherm 吸附等温线 Adsorption layer 吸附层Aero 美国氰胺公司的药剂品牌号 Aerofloat 美国氰胺公司的黑药牌号 Aerofloc 絮凝剂牌号 Aerofroth 起泡剂牌号Aeromine 阳离子型表面活性剂 Aero promoter 促进剂牌号 Aerosol 润湿剂牌号Aerosurf MG-98A 醚胺醋酸盐 Agglomerant 团聚的凝结剂Agglomeration flotation 团聚浮选Aggregate of large molecules 大分子团 Aiv-avid 亲气的Aiv-mineral adhesion 空气-矿物粘附 Alamine 胺的牌号 Alcohol 醇Alcohol frother 醇类起泡剂 Aliphat- 妥尔油脂肪酸牌号 Aliphatic alcohol 脂肪醇 Aliphatic acid 脂肪酸 Aliphatic amine 脂肪胺Aliphatic dydrocarbon 脂肪烃 Aliquat 苯胺盐牌号 Alkali 碱Alkaliuity 碱度,碱性 Alkane 链烷,烷烃 Alkoxy- 烷氧基Alkoxyamine 烷氧胺 Alkoxy benzene 烷氧基苯 Alkyl- 烷基Alkyl alcohol sulfate 烷基醇硫酸盐共12 页第7 页专业英语词汇矿物加工工艺常用词汇(一)1选矿-Mineral separation (ore dressing) 2设计-Design3工艺-Process (craftwork) 4初步设计-Initiative(preliminary) design 5流程-Flow(circuit) 6流程图-flowsheet7施工设计-working design 8设计方案-design project9粉碎-comminution 10 磨矿-grinding11浮选-flotation 12脱水-dehydration13干燥车间-drying shop 14尾矿-tailing15精矿-concentrate 16中矿-middles17精选-concentration 18粗选-first concentration20选矿机-concentrator 21矿浆ore pulp22分级-classification 22磨矿-grinding23磨矿机-grinding mills 24筛分-screen25粉碎-crush 26筛分机-screener27粉碎机-crusher 28颚式粉碎机-jaw crusher29圆锥粉碎机-cone crusher 30冲击式粉碎机impact crusher31辊式粉碎机-crusher rolls 32球磨机-ball mill33棒磨机-rod mill 34自磨机-autogenous mills35震动筛-vibratory screener 36分级机-classification equipment37浮选-flotation 38浮选机-flotation equipment39重选- gravity concentration 40特殊选-special selection41 浮选柱-flotation column 42脱水机-spin-drier43干燥机-drier 44总图-general chart45配置-deploy 46运输-transport47环境保护-environment protect 48场址-field location(site)49布置-lay 50设计资料-design information51粉碎流程-comminution flow 52磨矿流程-grinding flow(circuit)53浮选流程-flotation flow 54金属矿-metallic mines55非金属矿-non-metallic mines 56闭路-close circuit(loop)57闭路流程-close flow 58开路-cut circuit(loop)59开路流程-cut flow 60废水-liquid waste共12 页第8 页专业英语词汇61粉尘-powder 62噪声-yawp63污染-contamination 64沉淀-form sediment65净化-decontaminate 66输送-transportation67矿石-ore 68物料-material69给矿-feed ores 70给料-feed stuff71设备-equipment 72方案-project73标高-elevation 74通道-passage75维修-maintain 76检查-check77操作-operation 78化验-test、assay79检测-examine 80坡度-gradient81起重机-crane 82堆积-accumulation83细粒-granule、fine 84粗粒-coarse85尾矿坝-tailing dam 86矿仓-feed bin(storehouse)87粉矿仓-crushing pocket 88产品仓-product bin(storehouse) 89砂泵-pump 90立式泵-stand pump91卧式泵-horizontal pump 92耐酸泵-acid-proof pump93耐碱泵-alkali-resistant pump 94勘察-reconnaissance95地形-landform 96工程-engineering97设计步骤design process 98规模-scale99选矿厂-concentrating mill 100设计内容design content(二)1 comminution-粉碎2 comminution engineering-粉碎工程3粉碎机-comminuter 4粉碎动力学-comminution kinetics 5筛分曲线图-screen analysis chart 6筛孔-screen aperture7筛面-screen area 8筛条screen bar9筛框-screen box 10筛选厂-screen building11筛分机生产能力screen capacity 12筛分槽-screen cell13筛布-screen cloth 14筛分screen classification15筛孔-screen hole 16筛分车间-screenhouse17筛分分析-screen analysis 18滚筒筛-screening-drum19筛分效率-screening efficiency 20筛分速率-screening rate共12 页第9 页专业英语词汇21筛网-screen mesh 22筛制、筛比、筛序-screen scale23筛孔尺寸-screen size 24套筛-screen set25筛序-screen size gradation 26筛余物screen tailings27筛下产品-screen throughs(underflow.undersize) 28可碎性crushability 29可碎性系数-crushability factor 30碎矿仓-crushed ore pocket31粉碎产品-crushed product 32粉碎粒度-crusher size33粉碎腔-crushing cavity 34粉碎厂-crushing plant35粉碎系数-crushing coefficient 36粉碎工段-crushiong section37助磨剂-grinding aid 38磨球-grinding ball39 磨矿负荷-grinding charge 40磨矿效率-grinding efficiency41磨矿-grinding ore 42磨砾-grinding pebble43磨碎能力-grinding property 44研磨试验grinding test45磨矿设备-grinding unit 46磨矿速度-grinding rate47磨矿功率-grinding power 48磨矿车间-grinding plant49可磨性-grindability 50可磨性指数-grindability index51可磨性指标-grindability rating 52可磨性试验-grindability test53研磨工-grinder 54磨工车间-grindery55磨矿动力学-grinding kinetics 56粉碎能-crushing energy57粉碎机给矿口-crushing mouth 58粉碎面-crushing face59粉碎力-crushing force 60粉碎机进料口-crusher throat61筛分动力学-screen kinetics 62选厂矿仓-mill bin63 选厂中矿mill chats 64选厂配置mill configuration65磨过的矿石-milled ore 66磨机给料-mill feeder67选厂给矿-mill-head 68研磨作用-milling action69磨机衬里mill liner 70入选品位milling grade71入选品位矿石milling-grade ore 72磨矿机milling-grinder73细碎、精磨-milling grinding 74磨矿介质-milling medium75磨矿法-milling method 76选矿作业-milling operation77选矿厂-milling plant 78选厂矿泥-milling slime79选厂厂址-mill site 80磨机负荷-mill load81选矿工(工长)millan 82磨机需用功率-mill power draft 83选矿质量控制mill puality control 84选矿取样-mill sampling共12 页第10 页85磨机外壳-mill shell 86磨机矿浆-mill slurries87磨石-millstone 88选矿厂储矿仓mill-storage89选厂尾矿-mill tail 90选矿用水-mill water91磨矿机溶液-mill solution 92选矿厂建筑师-millwright93分级沉淀-class setting 94矿粉-mineral fine95分级-classification 96分级溢流-classifier overflow97分级返砂-classifier sand 98分级机-classifier99分级筛-classifying screen 100分级箱-classifying box(三)1品位-grade 2精矿品位-concentrate grade3尾矿品位-tailing grade 4尾矿场-tail area(pile)5尾矿仓-tailing bin 6尾矿滤饼-tailing cake7尾矿坝-tailing dam 8尾矿池-tailing pond(pit)9取样-taking cut(sampling) 10滑石talc11蓝晶石-talc blue 12 试样缩分-sample division13 分样器-sample divider 14精矿取样-concentrate sampling15中矿取样-middles sampling 16尾矿取样-tailing sampling17浓缩-thickening 18精矿浓缩-concentrate thickening19选矿流程-concentrating circuit 20精选机-concentrating mcching21试样缩分-sample reduction (splitting) 22矿物组成-mineralcomposition23矿物组分-mineral constituent 24矿床-mineral depost25矿物-mineral 26选矿方法mineral dressing method27选矿厂-concentrating mill 28选矿ore dressing,mineral separation29矿物分析-mineral analysis 30矿物组合-mineral association31 试样袋-sample sack 32矿床-deposit33矿物岩相facies 34矿物纤维-mineral fiber35固、气界面-mineral-air interface 36固、液界面-mineral-water interface37固、气、液接触mineral-air-water contact 38矿物颗粒-grain39矿物鉴定-mineral identification 40矿物资源-interest41矿物解离-mineralliberation 42矿物特性mineral character43矿物储量-mineral reserve 44矿物(成分)检验mineral logical examination 45扑收剂-Minerec,flotigan, 46精矿回收率concentrate recovery47中矿回收率middles recovery 48精选concentration49附着精矿气泡concentratr-loaded bubble 50精选机-concentrating maching51分选判据-concentration criterion 52富集比-concentration factor53选矿摇床-concentration table 54选厂流程concentrator flow5选厂流程图concentrator flow sheet 56试样品位-sample grade57絮凝剂-flocculant 58絮凝-floculate59絮凝物-flocs 60絮凝浮选floc flotation61絮凝作用flocculation 62浮选机flotation unit63浮选剂- flotation agent 64整排浮选机flotation bank65浮选槽- flotation cell 66浮选能力flotation capacity67浮选精矿- flotation concentrate 68浮选尾矿flotation rejects69浮选中矿- flotation middles 70浮选设备flotation equipment71浮选泡沫-flotation froth 72浮选动力学flotation kinetics73浮选浸出法- flotation leaching method 74浮选厂flotation mill75浮选油-flotation oil 76浮选矿浆- flotation pulp77浮选速度-flotation rate 78浮选试验flotation test79单槽浮选机- flotation unit cell 80浮选摇床- flotation table81摇床浮选- flotation tabling 82起泡剂Flotol83流程图-flow line 84工艺流程图-flow process chart (flow sheet) 85可选(洗)性-washability 86可选性特性- washability characteristic87可选性曲线- washability curve 88可选性指数- washability number89可选性试验- washability test 90可浮性-flotability91可浮性曲线-flotability curve 92粒度特性-granularity93粒度分级试验grading test 94结构-texture95构造-tectonic(structural) 96致密结构-compact texture97斑状结构porphyritic texture 98 粒度分析-granularmetric analysis99采样-sample collecting 100分样器-sample divider。
染整专业英语Unit 1
A liquid desizer for efficient removal from the sized fabric
A Cold Scouring Bleaching Agent. Leveling Agent A dispersing agent for disperse dyes. High performance non formaldehyde dye fixing agent.
Functional groups
线性烷基苯磺酸盐 stearic
硬脂软脂-
palmitic
Sulfosuccinate esters Quaternary ammonium salts Zwitterionic surfactants
lauric oleic octylcetyl-
月桂油辛十六-
Polyoxyethylenated aklylphenols 聚氧乙烯烷基酚
Bases 盐酸 硫酸 柠檬酸
甲酸 乙酸 碳酸 磷酸二氢钠 硼酸
Sodium hydroxide Potassium hydroxide Sodium metasilicate
Trisodium phosphate Sodium carbonate Ammonia Disodium phosphate Sodium bicarbonate
The Primacy effect
Informations at the beginning
LTM STM
of the sequence have larger probability to be recalled compared to the ones in the middle , and are also more likely to become LTM.
混凝土硫酸盐侵蚀机理及影响因素
小于 0. 45、C3 S含量低于 8%的混凝土是相对安全 的 。文献 [ 12 ]认为 ,在硫酸钠环境下 ,水胶比低 ,有利 于抗侵蚀 。如水灰比 0. 5 和 0. 35, 浸泡时间为一 年 ,强度减少分别为 39%和 26%。但在硫酸镁环境 下 ,水胶比低 ,似乎加重了硫酸盐侵蚀 ,如水灰比 0. 5和 0. 35,强度减少分别为 62%和 81%。对于掺有 活性掺合料的水泥也得到类似的结果 。 2. 2 外部因素 2. 2. 1 硫酸根离子浓度
钙矾石的生成被认为是体积增加了 2. 5 倍 ,导 致膨胀应力的产生 ,而使混凝土开裂破坏 ,混凝土的 开裂又使硫酸根离子更容易渗透到混凝土内部 ,产 生恶性循环 。但对钙矾石的膨胀机理至今仍未清 楚 ,有人认为钙矾石的结晶压力导致了膨胀压力 ;也 有人认为是由于结晶差的钙矾石在碱性环境下吸水 膨胀导致了膨胀压力 [ 5 ] 。钙矾石生成的速度与铝 酸根的来源有很大的关系 ,在很多情况下 ,钙矾石形 成的速度由含铝相的溶解速度所决定 [ 6 ] 。钙矾石 形成的量与膨胀之间的关系还没有得到一个很好的 相关性 [ 4 ] 。 1. 4 C2S2H 和碳硫硅钙石 (CaSiO3 ·CaSO4 ·CaSO3 ·15H2 O )
硬化混凝土在硫酸盐溶液中石膏的形成可由化 学方程式 ( 1)和 ( 2)表示 。有观点认为石膏的形成 引起膨胀 ,体积变为原来的 1. 2倍 ,使混凝土受到膨 胀压力的作用 。为研究石膏的形成是否产生膨胀 , 必须排除钙矾石的影响 。B ingTian[ 1 ]用 5%硫酸盐 溶液浸泡 C3 S表明 ,浸泡有 4周的潜伏期 ,潜伏期一 过 , C3 S便以较大的速率膨胀 ,浸泡至 230 天 ,膨胀 达到 1. 05%。M anusanthanam[ 2 ]的试验结果同样表 明 ,在 4. 44%硫酸钠中浸泡 C3 S存在潜伏期 , 32 周 前膨胀很小 , 32周后开始膨胀 ,浸泡至 41周膨胀为 0. 22%。也有观点认为石膏的形成并不引起膨胀 , Hansen[ 3 ]认为氢氧化钙和硫酸根离子由通过 - 溶液 机理在毛细孔中形成固态石膏 ,不可能占有比孔隙 体积和溶解并参加反应的固态氢氧化钙体积之和更 大的体积 , M ather[ 1 ] 支持 Hansen 的观点 ,他认为石 膏是硫酸根离子和钙离子由通过 - 溶液机理生成 。 普遍都认为石膏的形成导致混凝土刚度 、强度的降
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a r X i v :h e p -l a t /9809113v 1 15 S e p 19981Free energy of an SU(2)monopole-antimonopole pair∗Ch.Hoelbling a ,C.Rebbi a and V.A.Rubakov baBoston University Physics Department 590Commonwealth Avenue Boston MA 02215,USAbInstitute for Nuclear Research of the Russian Academy of Sciences 60th October Anniversary Prospect 7a Moscow 117312,Russian FederationWe induce an external Z 2monopole-antimonopole pair in an SU(2)lattice gauge system and measure its free energy as a way to probe the vacuum structure.We discuss the motivation and computational methodology of the investigation and illustrate our preliminary results.It is well known that some Higgs theories with non-Abelian gauge group admit stable monopole solutions[1,2].With large gauge groups,as in grand unified theories,the residual unbroken gauge group can be non-Abelian.It is then in-teresting to determine the properties of the inter-action induced among monopoles,or,as we will consider in this paper,beteween a monopole and an antimonopole,by the quantum fluctuations of the unbroken group.Beyond the relevance that such interaction may have for the original theory,it can shed light on the low energy properties of the residual gauge theory itself.From the point of view of the unbroken theory,to a very good approximation the monopoles act as static point sources.The way to incorporate such sources in an SU (N )lattice gauge theory was spelled out in Refs.[3,4],which built on earlier results es-tablished in a seminal paper by ’t Hooft [5]and in Refs.[6–8].We will follow closely the treat-ment of Ref.[4].In a three dimensional theory,a monopole-antimonopole pair can be introduced within two cubes of the lattice by the replacement βTr U P →β′Tr U P ≡z n βTr U P for all the terms in the action corresponding to plaquettes trans-versed by a path joining the centers of the two2screening,whereas a1/r behavior or a linearly rising behaviour would characterize a Coulomb phase or a phase with condensation of electric charges,respectively.It is also noteworthy that the monopole and the antimonopole form two an-chors for a center vortex.Recent investigations (cfr.Refs.[11–14])have emphasized the role that such vortices play in confinement.The calcula-tion which we present here can be reinterpreted as the calculation of the cost in free energy to create a center vortex spanning a certain distance within the lattice.If such excess free energy quickly satu-rates(screening),then the vacuum should indeed exhibit a condensate of center vortices.The numerical calculation of a free energy is notoriously difficult.We have been able to ob-tain reasonably accurate results with acceptable amounts of CP time by combining a Monte Carlo simulation with the multihistogram method[15]. We consider a modified SU(2)lattice gauge the-ory with Wilson action,defined over a N x×N y×N z×N t hypercubical lattice with peri-odic boundary conditions.The modification con-sists in the fact that,for all the x−y plaque-ttes P′having a lower vertex with coordinates x=0,y=0,0<z≤d,0≤t<N t,the coupling constantβis replaced withβ′.These are the pla-quettes that cross the sheet joining the worldlines of the monopole and antimonopole at separation r=da(a being the lattice spacing).We denote the partition function of this system by Z(β′,β). We are interested in the free energyF(r)=−1Z(β,β) (1)Let us defineρ(E)= dUδ[E− P′Tr U P′]e P=P′βTr U P/2(2)If we perform a simulation withβ′set to a certain valueβi and record in a histogram the frequency n i(E)of occurrences of a certain value of E,we willfindn i(E)=ρ(E)eβi E/2N h i n i(E)eβi E/2Z(k)i(5)We start from Z(0)i=1and iterate:the values ofZ(k)iat convergence are proportional to the cor-responding Z(βi,β).As a technical improvementin the implementation of the histogram method,applicable to the case where the measured vari-able covers a continous range,we have allocatedthe values of E to the four neigboring end-pointsof the histogram intervals with the weights of acubic interpolation.This procedure reduces sub-stantially the total number of histogram subdivi-sions one must use to obtain accurate results.We illustrate here the results we have obtainedwithβ=2.6,N x=N y=20,N z=40and thetwo time extents N t=16and N t=6,which placethe system in the confined and deconfined phasesrespectively.We have used a combined multi-hitMetropolis overrelaxation algorithm,with5000equilibrating iterations and4000to20000mea-surements separated by50iterations.The mea-surements themselves have been performed by av-eraging over384upgrading steps of the links inthe plaquettes P′as a variance reduction tech-nique.In Figure1we show the histograms for adefinite separation of the monopole-antimonopolepair.In Figure2we show our results for the freeenergy of the pair.The calculation is computerintensive,because one must perform separate cal-culations for all separations of the pair and for allthe intermediate values ofβ′.However it is quitefeasible with present day computer resources.Wehave written a Fortan90code which,paying someattention to the distribution of the data but with-out resorting to any special programming trickslike coding critical subroutines in assembler,runsat approx.40%of peak speed on the SGI-CrayOrigin2000,with very satisfactory scaling.Withthis performance,the cost of the data presentedin this paper is of the order of a few thousand pro-cessor hours,which is rather modest by today’s3−1.0−0.50.00.5 1.0ΣP’Tr(U P’)/N P’f r e q u e n cy Figure 1.The overlap of histograms at β=2.6and different β′.The monopole separation is 2a and N t =6.246monopole pair separation0.00.20.40.60.81.01.21.41.61.82.0f r e e e n e r g yFigure 2.Free energy of a monopole-antimonopole pair at different separations for β=2.6and N x ×N y ×N z =20×20×40.The cir-cles are with N t =16in the confined phase,the diamonds with N t =6in the deconfined phase.standards of supercomputing.The results in Figure 2show that the inter-action of the pair is screened both in the con-fined and deconfined phases.The lines in the figure correspond to exponential fits exp(−d/l )with l =0.8300and l =0.7828for N t =16and N t =6,respectively.We have also computed the free energy of a single monopole adopting free boundary conditions for the z =0,N z boundaries of the lattice (we maintained periodic boundary conditions in all other directions)and the results are in agreement with the free energy of the pair for large separation.Our investigation is still in progress.We plan to repeat the calculation with a smaller value of βto verify scaling and to study the behavior of the free energy of a single monopole as one goes across the deconfining tran-sition.It would also be interesting to extend the calculation to other systems,especially to models which are expected to possess a varied structure of electric and magnetic confinement phases.REFERENCES1.G.’t Hooft,Nucl.Phys.B79(1974)276.2. 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