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化学专业英语文献

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不知道,随便给你一个疏水缔合型聚合物P(AMTA)溶液性质的研究疏水缔合型水溶性聚合物是指在聚合物亲水性大分子链上带有少量疏水基团的一类水溶性聚合物。在聚合物水溶液中,疏水基团之间由于憎水作用而发生聚集,使大分子链产生分子内和分子间缔合。在临界缔合质量分数以上,形成分子间缔合为主的超分子结构,增大了流体力学体积,故具有较好的增黏性。在盐溶液中,由于小分子电解质的加入增加了溶液极性,使疏水缔合作用增强,表现出明显的抗盐性质。 疏水缔合型水溶性高分子很难合成,且不易表征,把疏水部分连接到水溶性聚合物链上,一般采用胶束共聚合或者使用具有表面活性的大单体进行共聚,胶束聚合需要在体系中加入大量的表面活性剂,这就增加了后处理过程的复杂性。利用表面大单体共聚合,需要事先合成大单体,这方面的技术也有相当大的难度。作者采用丙烯酸十四酯作为疏水单体,直接用沉淀聚合法制备疏水缔合型聚合物P(AM/TA)共聚物,从而使共聚反应及其产物的后处理过程较为简单易行。并用凯达尔定氮法表征共聚物的组成,研究共聚物的溶液性能和对苯丙乳液的增稠性。 1实验 1.1试剂 丙烯酰胺(AM),质量分数不少于985%,根据文献提供的方法提纯;N,N-甲基甲酰胺(DMF),分析纯;甲醇、氯化钠,化学纯;丙烯酸十四酯(TA),实验室自制;苯丙乳液由福建省福州树脂有限公司提供。 1.2P(AM/TA)共聚物的合成 称取一定量的AM和TA单体,用DMF溶解,转入三颈瓶中,通氮除氧。升温至80℃,加入引发剂反应4h,过滤,产物用甲醇洗涤多次,以除去未反应的单体。40℃真空干燥至恒重。 1.3分析测试 凯达尔定氮法测定共聚物的组成。用乌氏黏度计测定共聚物溶液特性黏度[η],测试温度为(30±O1)℃。聚合物溶液表观黏度用NDJ-I型旋转黏度计测定。 2结果与讨论 2.1共聚物稀溶液性质不同疏水基团摩尔分数的P(AM/TA)共聚物在蒸馏水和w(NaCl)=5%的溶液中的特性黏度[η]值列于表1。 聚合物的[η]正比于溶液中大分子线团的流体力学体积,因而能反应大分子线团收敛、卷曲的程度。从表1可知,随共聚物的TA链节摩尔分数的增加,其水溶液的[η]值逐渐减小,在w(NaCl)=5%的溶液中也是持续减小。这是因为在稀溶液中,疏水基团缔合以分子内缔合为主,随着TA摩尔分数的增加,分子内缔合增强,导致分子链卷曲。在盐溶液中,由于离子电荷的作用,使疏水链节分子内缔合力增强,分子链收缩,因而[η]值也持续下降。 2.2疏水基团TA摩尔分数对聚合物溶液黏度的影响 图1和图2分别表示P(AM/TA)系列共聚物及PAM在蒸馏水和w(NaCl)=5%的溶液中表观黏度与聚合物质量分数的关系曲线。PAM溶液黏度随其质量分数的增加而平缓上升,而疏水共聚物溶液的质量分数为3O%~4O%时其黏度急剧增加,表明疏水基团聚集而导致分子间缔合,形成了物理交联网络。此时共聚物溶液的质量分数即是临界缔合的质量分数。如图1所示,随TA摩尔分数增加,共聚物溶液的黏度显著增加。当疏水基团摩尔分数较高时,其溶液黏度随质量分数增加的速度更快,共聚物的临界缔合质量分数降低。如图2所示,加入Nacl溶液后,溶液表观黏度有较大提高,如质量分数为O%的P(AM/TA)-1 5聚合物溶液在20℃,转速为6r/min时,黏度达OmPs,而在水溶液中的黏度只有374mPa·s。不同TA摩尔分数的聚合物的质量分数均较其在纯水中低。Hydrophobically associating polymer P (AMTA) the nature of the study solution Hydrophobically associating water-soluble polymer is the hydrophilic polymer with a small amount of macromolecular chain hydrophobic group of a class of water-soluble Aqueous solution in the polymer, the hydrophobic groups and between the role as a result of hydrophobic aggregation occurred, so that large molecules have a molecular chain and inter-molecular Associating the critical mass fraction of the above, the formation of intermolecular association based supramolecular structure, increases the volume of fluid mechanics, it has good by In salt solution, because of the addition of small molecule electrolyte solution increased polarity, so that co-operation with enhanced hydrophobic association, shows that the nature of the Hydrophobically associating water-soluble polymer-based synthesis is difficult and not easily characterized, in part to hydrophobic chains connected to the water-soluble polymer, the general use of micellar copolymerization, or the use of the large surfactant monomer to copolymerization, polymer micelles need in the system by adding a large number of surface-active agent, which, after an increase of the complexity of the The use of the surface monomer copolymerization, the need for prior synthesis of large monomer, this technology also has considerable Author tetradecyl acrylate used as a hydrophobic monomer, the direct use of precipitation polymerization Preparation of hydrophobically associating polymer P (AM / TA) copolymers, so that the product of copolymerization and post-processing is more simple and easy And characterization of nitrogen determination Kedar copolymer composition, study the solution properties of copolymers of styrene-acrylic emulsion and of the 1 Experimental 1 Reagents Acrylamide (AM), the mass fraction of not less than 985 percent, according to documents provided by purification methods; N, N-dimethylformamide (DMF),分析纯; methanol, sodium chloride, chemical pure; acrylic 10 four acetate (TA), laboratory-made; styrene-acrylic emulsion resin from Fuzhou in Fujian Province L 2P (AM / TA) Copolymer Check that a certain amount of monomer AM and TA, using DMF dissolved into three-neck bottle, pass oxygen Warming to 80 ℃, reaction by adding initiator 4h, filtering, washing the product several times with methanol to remove unreacted 40 ℃ vacuum drying to constant 3 Analysis and Testing Determination of nitrogen Kedar will be the composition of Determination of intrinsic viscosity with copolymer solution viscosity [η], the test temperature (30 ± O1) ℃ Apparent viscosity of polymer solution with NDJ-I-type rotary viscometer 2 Results and Discussion 1 Dilute Solution Properties of Copolymers of different mole fraction of hydrophobic groups of the P (AM / TA) copolymers in distilled water, and w (NaCl) = 5% of the solution intrinsic viscosity [η] values listed in Table Polymer [η] is proportional to the solution of the fluid dynamics of macromolecular coil volume, which can respond to the convergence coil macromolecules, the degree of We can see from Table 1, with the copolymer chain of the TA increase in mole fraction, the aqueous solution of [η] value decreases in w (NaCl) = 5% of the solution is continued to This is because in dilute solution, the hydrophobic group to intramolecular association based association, with the mole fraction of the increase in TA, to enhance intramolecular association, resulting in the molecular chain In salt solution, because of the role of ionic charge, so that intramolecular hydrophobic chain to enter into force enhancement, molecular chain contraction, so [η] value continued to TA hydrophobic group 2 mole fraction of polymer solution viscosity on the impact of figures 1 and 2, respectively, P (AM / TA) series of copolymers and PAM in distilled water, and w (NaCl) = 5% in the apparent viscosity of the solution and the relationship between the mass fraction of polymer PAM solution viscosity with the increase of mass fraction of gentle rise, and the hydrophobic copolymer solution for the mass fraction of 3O% ~ 4O%, when a sharp increase in viscosity, indicating that aggregation of hydrophobic groups and lead to intermolecular association, forming a physical crosslinking网络 At this point the mass fraction of copolymer solution that is the critical mass fraction of the As shown in Figure 1, with the mole fraction of TA increased, the viscosity of copolymer solution increased When the mole fraction of hydrophobic groups is high, the solution viscosity increases with the mass fraction of the faster, the critical aggregation copolymer mass fraction As shown in Figure 2, by adding Nacl solution, the solution has greatly enhanced apparent viscosity, such as the mass fraction of O% for the P (AM / TA) -1 5 polymer solution at 20 ℃, rotation speed 6r/min , the viscosity of OmPs, and viscosity in aqueous solution only 374mPa TA different mole fraction of the mass fraction of polymer in water were

化学专业英语论文

Study on Adsorption of Heavy Metals by Suspended Sediment of Juma River 拒马河悬浮沉积物对重金属的吸附—解吸研究 Effect of Cd-Pb pollution on cole growth behavior and its accumulation effect of heavy metals in soil 土壤镉、铅污染对油菜生长行为及重金属累积效应的影响 Study on the Adsorption of Heavy Metals Ion onto Vermiculite 蛭石对重金属离子吸附作用的研究 A Perliminary Study on Concentrating Heavy Metals By Sabina Chinensis Seadlings 桧柏富集重金属研究初报 Iron presents in abundance as variety of Fe(III) oxides in Fe 在地壳中含量丰富,通常以各种Fe(III)氧化物的形式存在。 Chemical behavior of heavy metals in rhizosphere——Ⅱ The rhizosphere effect of desorption of adsorbed Cu in 重金属在根际中的化学行为——Ⅱ土壤中吸附态铜解吸的根际效应 STUDY OF POLYSILOXANE WITH AMINO ACID SIDE CHAIN SUPPORTED CATALYSTS Ⅲ THE SYNTHESIS, HYDROGENATION ACTIVITY AND XPS STUDY OF POLY-γ-(L-SERINE)PROPYLSILOXANE PALLADIUM CATALYSTS 含氨基酸侧链的有机硅高分子催化剂——Ⅲ聚γ—(丝氨酸基)丙基硅氧烷钯催化剂的合成、加氢活性及XPS研究 A Study of Monitoring Heavy Metals and SO_2 in Air Using Moss-bags as Bio-monitors 苔袋法监测大气重金属和SO_2污染 STUDY ON HIGH EFFICIENT REMOVAL METHOD OF COD_(cr) IN DIPDYE OUTLET WATER 印染废水COD_(cr)高效去除法的研究 The absorptive capacity of soil to heavy metals and its pollution levels were in the following orders:Cd>Pb>Cr>Cu>As>Zn>Ni>Mn>F 土壤对重金属元素的吸附及污染程度 :Cd >Pb >Cr >Cu >As>Zn >Ni>Mn >Fe。

有机化学英语论文Abstract In this work the effects of the microporosity and chemical surfaceof polymeric adsorbents on adsorptive properties of phenol Textural parameters of four kinds of polymeric resins namely AB-8 D4006 NKA-II and D16 resin were separately measuredby ASAP The surface chemistry of these polymeric resins was determined by means of inverse gaschromatography (IGC) and diffusereflectance infrared Fourier transform spectroscopy (DRIFTS) Static equilibrium adsorption experiments were carried out to obtain theisotherms of phenol on the polymeric It was shown that NKA-II and AB-8 resin possessed relatively high BET surface areas andmicropore volumes while D4006 and D16 resin possessed comparatively low BET surface areas and micropore The results of IGCexperiments revealed that NKA-II resin had extraordinary high specific component of the free energy of adsorption both for polar acetone andbenzene probe and thus extraordinary strong surface polarity compared to the other polymeric It was also found that the isotherm ofphenol on NKA-II was much higher than that on the other polymeric resins due to its strongest surface polarity and largest micropore volumeamong four kinds of These experimental observations indicated that adsorption of phenol on the polymeric resins depended greatly ontheir microporosity and surface The well-developed microporosity and the strong surface polarity would improve the adsorptionof phenol on the polymeric 2004 Elsevier BV All rights Keywords: Polymeric resin; Phenol; Porosity; Surface chemistry; Inverse gas chromatography

高效的重金属去除聚合物纳米保湿由铁(3):行为和XPS研究氧化物 文摘:本研究开发了一种聚合物混合吸着剂(HFO-001)为高效的重金属去除(如铅(2)、Cd、铜(II),(2)]不可逆转的浸渍水合氧化(铁(III)在cation-exchange HFO)粒子(R-SO3Na D-001树脂),这种现象的潜在机制的基础上揭示x射线光电子能谱(XPS)的研究。HFO-001结合了出色的处理,和摩擦阻力流量特性,传统的cation-exchange树脂与特定的关系入手,对重金属HFOs阳离子。D-001相比,吸附选择性的HFO-001对铅(II)、铜(二)、(2)Cd大大提高从Ca(II)中更大的浓度。结果表明,柱吸附能力的工作是4-6 HFO-001 D-001倍以上三方面的重金属去除从模拟电镀水(pH ~ 0)。同样,HFO-001尤为有效杀灭多种微量铅(II)和Cd(2)从模拟自然水域达到饮用水标准,以治疗量高于D-001数量级。性能优越的HFO-001归因于Donnan膜效应所举办D-001以及纳米粒子交互作用的特殊HFO浸渍对重金属阳离子作为进一步证实,由XPS研究吸附铅。更有吸引力,疲惫的HFO-001串珠可以有效地解决由HCl-NaCl再生(pH值(3),没有任何有意义的能力的重复使用的损失。 1。简介:重金属注入受纳水体环境问题仍然是重要的,现在正在日益规范作为新的法规限制金属废水推进亿欧元(合ppb),甚至更低(美国EPA,2004年的水平,中国2008年美国环保署)。在现有技术、碱性降水重金属去除历来是首选的技术会议,(ppm)管理水平为微量铅(如第(二)、(二)、Cd等。]在direct-discharge废水点源,然而,这技术通常是限于≥污水浓度百万分之一的有限溶解无定形的金属氢氧化物阶段和效率低下的商业固液分离装置(代尔等,1998年,2003年)。离子交换树脂,利用strong-acid cation-exchange是另一个高效的技术,为有效去除工业废水中重金属的(Dabrowski等,2004,康等,2004;Kurniawan等,2006)或污染地下水(Vilensky等,2002;Dabrowski等,2004年)。然而,一个简单的交换过程中只被静电相互和非特异性为重金属去除(Demirbas等,2005;Carmona等,2008年)。

化学专业英语文献翻译摘要

两个多孔金属有机骨架材料纳入exotridentate桥联配体3 -氨基- 1 2,4 - triazolate(AmTAZ)已通过二级衔接阴离子合成的变化:[Zn3(AmTAZ)3S技术](硝酸)·(水) (1 °(水)) 和Zn7(AmTAZ)8(碳酸)2(OH)2的· 2(乙醇)(2 ° 2(乙醇);乙醇)乙醇)。 1 ·(H2O)的晶体立方空间群格I23,并从三角Zn3S是桥接成阳离子三维(3D)的网络,通过配体与AmTAZ硝酸盐和水分子中的腔居住单位建造。 2 · 2(乙醇)单斜晶系,空间群为C2 / c,显示出复杂的三维网络从七晶体学独特的锌

At present, the industrial route for the production of cyclohexanone cyclohexane oxidation, there are two First cyclohexane catalytic oxidation, and the other is non-catalytic oxidation of The traditional process of production of cyclohexyl alcohol and cyclohexanone (KA oil), the process is complex and serious Therefore, to find a new energy to maximize cyclohexane conversion rate and the selectivity of the alcohol and ketone oxidation method has great Metal porphyrin catalysts to improve the role of traditional crafts shortcomings, showing high activity and selectivity is the main object of study of the catalytic oxidation of The conversion rate of cyclohexane, cyclohexyl alcohol selectivity of cyclohexanone as the indexes were tetraphenylporphyrin copper (TPPCu), four (m-methylphenyl) porphyrin copper (Tm-MPPCu) (3,4 - dimethylphenyl) porphyrin copper (TDMPPCu) and other three metal porphyrin catalyzed oxidation of cyclohexane synthesis of cyclohexyl alcohol and cyclohexanone experiments, the purpose is to explore the tetraphenylporphyrin copper even methyl substituents at the benzene ring, the number of methyl substituted biomimetic catalytic oxidation of cyclohexane The experimental results show that: (1) within the scope of this experimental study, with methyl substituents on the benzene ring of the tetraphenylporphyrin copper, and its catalytic performance has improved, methyl substituted with a base number is more catalytic properties to improve more; (2) three metalloporphyrins have to study indicators of conditions, the optimum catalyst for is TDMPPC Suitable reaction conditions: the pressure 0MPa, air flow 10-12m3 / h, the catalyst concentration of 4 × 10-6g / g conditions, the optimum reaction temperature of 150 ° C, the reaction time was Under these conditions, the cyclohexane conversion rate of 23% of alcohol and ketone selectivity of 1%Keywords: cyclohexane; Metalloporphyrins; catalytic oxidation; methyl substituents the number of

化学专业英语论文翻译

高效的重金属去除聚合物纳米保湿由铁(3):行为和XPS研究氧化物 文摘:本研究开发了一种聚合物混合吸着剂(HFO-001)为高效的重金属去除(如铅(2)、Cd、铜(II),(2)]不可逆转的浸渍水合氧化(铁(III)在cation-exchange HFO)粒子(R-SO3Na D-001树脂),这种现象的潜在机制的基础上揭示x射线光电子能谱(XPS)的研究。HFO-001结合了出色的处理,和摩擦阻力流量特性,传统的cation-exchange树脂与特定的关系入手,对重金属HFOs阳离子。D-001相比,吸附选择性的HFO-001对铅(II)、铜(二)、(2)Cd大大提高从Ca(II)中更大的浓度。结果表明,柱吸附能力的工作是4-6 HFO-001 D-001倍以上三方面的重金属去除从模拟电镀水(pH ~ 0)。同样,HFO-001尤为有效杀灭多种微量铅(II)和Cd(2)从模拟自然水域达到饮用水标准,以治疗量高于D-001数量级。性能优越的HFO-001归因于Donnan膜效应所举办D-001以及纳米粒子交互作用的特殊HFO浸渍对重金属阳离子作为进一步证实,由XPS研究吸附铅。更有吸引力,疲惫的HFO-001串珠可以有效地解决由HCl-NaCl再生(pH值(3),没有任何有意义的能力的重复使用的损失。 1。简介:重金属注入受纳水体环境问题仍然是重要的,现在正在日益规范作为新的法规限制金属废水推进亿欧元(合ppb),甚至更低(美国EPA,2004年的水平,中国2008年美国环保署)。在现有技术、碱性降水重金属去除历来是首选的技术会议,(ppm)管理水平为微量铅(如第(二)、(二)、Cd等。]在direct-discharge废水点源,然而,这技术通常是限于≥污水浓度百万分之一的有限溶解无定形的金属氢氧化物阶段和效率低下的商业固液分离装置(代尔等,1998年,2003年)。离子交换树脂,利用strong-acid cation-exchange是另一个高效的技术,为有效去除工业废水中重金属的(Dabrowski等,2004,康等,2004;Kurniawan等,2006)或污染地下水(Vilensky等,2002;Dabrowski等,2004年)。然而,一个简单的交换过程中只被静电相互和非特异性为重金属去除(Demirbas等,2005;Carmona等,2008年)。

灵格斯,谷歌金山词霸合作版,有道等,可以在线翻译。灵格斯可以下载化学专业词典。但是软件翻译局限性很大,自己还是要懂一些外文命名。是在不行可以先看一些相关中文文献,熟悉常用词。

impossible between members of different species because genitals of males and females are structurally incompatible or because molecules on the surfaces of sperm and egg fail to A final type of prezygotic mechanism is temporal isolation, in which time-related environmental cues that trigger reproductive processes are different for related 有时,产生前合子隔离的差异涉及了隔离机制。即,由于生殖器结构不匹配或精卵分子表面不结合而使不同种群成员间不能自然结合。最后一类前合子机制是暂时隔离,与时间有关的环境因素触发了相关物种的不同繁殖过程。

医学专业英语文献

seek68文献馆中外数据库汇总,覆盖学科全面。包括医学。包括以下数据库Pubmed是美国国家医学图书馆(NLM)所属的国家生物技术信息中心(NCBI)于2000年4月开发的一个基于WEB的生物医学信息检索系统。免费Ovid(Ovid Technologies)在国外医学界被广泛应用。scintific research从事国际学术会议论文集的出版和检索,以及专业学术期刊、专著的出版发行。内容涵盖物理、化学、医学、生物、数学、通信、计算机等领域Clinical trials提供了网站临床试验注册辅导,登记了各种观察性研究和干预性研究,包括药物、器械和手术等干预方式。其注册和查询临床试验均为免费~Springer生命科学、医学、数学、化学、计算机科学、经济、法律、工程学、环境科学、地球科学、物理学与天文学。PLOS医学生的首选外文文献搜索库,这里可以搜索到世界医学领域最新、最专业的研究结果,并且免费查阅!Science美国的一个科学网站,是大型综合性、多学科、核心期刊引文索引数据库。免费!ClinicalKey临床精钥是信息分析公司爱思唯尔(Elsevier)推出的一个临床决策支持工具,帮助医生快速获取准确、简洁、世界前沿的循证医学知识。HighWire Press是全球最大的提供免费全文的学术文献出版商。涵盖生物科学、人文、医学、物理科学、社会科学等大类。标为free的可免费访问全文。

可以在以下文献网站中检索需要的医学文献:UpToDate数据库用于协助临床医生进行诊疗上的判断、决策的循证医学数据库。Thieme是一家拥有百年历史的医学和科学出版社。Karger出版的学科领域涵盖了医学的传统领域及现代医学的最新发展。美国医学会(American Medical Association, AMA)是世界三大医学会之一HighWire Press是全球最大的提供免费全文的学术文献出版商。涵盖生物科学、人文、医学、物理科学、社会科学等大类。标为free的可免费访问全文。Ovid(Ovid Technologies)在国外医学界被广泛应用。其Databases@Ovid包括300多种医学外文文献数据库,并可直接链接全文期刊和馆藏。Pubmed是美国国家医学图书馆(NLM)所属的国家生物技术信息中心(NCBI)于2000年4月开发的一个基于WEB的生物医学信息检索系统。seek68文献馆整合了大量的中外文献数据库资源。涉及各科领域,包括医学的各个分类。EMBASE内容涉及药学、临床医学、基础医学、预防医学、法医学和生物医学工程等。Clinical trials提供了网站临床试验注册辅导,登记了各种观察性研究和干预性研究,包括药物、器械和手术等干预方式。其注册和查询临床试验均为免费。ClinicalKey临床精钥是信息分析公司爱思唯尔(Elsevier)推出的一个临床决策支持工具,帮助医生快速获取准确、简洁、世界前沿的循证医学知识。

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