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英文论文在哪下载

知网上能下载的外文文献主要是期刊数据库中的国内出版的英文版期刊和会议数据库中的英文会议论文。还有其他合作的外文数据库springer、Taylor&Francis,你可以在中文的检索环境下去检索外文,这点对初学者比较适合,但是只能看到题录摘要。假如对外文文献要求较高、较全,建议你还是根据学科去选择专业的外文数据库查询会比较好。先搜索到“中国知网”主页;如果您是“中国知网”的用户则先在其主页登录,否则不允许下载全文;在“中国知网”的“工具栏”中选择CNKI知识搜索;进入到CNKI知识搜索的主页,在“全文文献”中输入要检索的英文关键字;搜索就可以 找到有关的英文文献。 在给你推荐两个常用的外文文献数据库,ScienceDirect和SpringerLink。

Open Access Library。Open Access Library(OA图书馆),在线数据库,里面的所有的文章都来自顶级著名的出版商和数据库,可以满足各个领域学者的需求。同时,那些已经评审或者未发表的文章都可以在线查看,以此提供学术交流的机会。读者可以用关键字在Open Access Library(OA图书馆)搜索下载完整的PDF格式的文章,这是不需要注册和交任何费用的。开放存取(Open Access,简称OA)是基于互联网不受限制的访问同行评审的学术期刊的机制。开放存取代表不受限制的访问和无限制的重用,这就是它为什么重要。开放存取正逐渐被应用于论文、学术专著和图书章节。它消除了价格障碍(订阅费、按次计费的费用)和许可障碍(大部分版权和许可限制)。根据Association of Research Libraries的解释,“开放存取”是在基于订阅的传统出版模式以外的另一种选择。这样,通过新的数字技术和网络化通信,任何人都可以及时、免费、不受任何限制地通过网络获取各类文献,包括经过同行评议过的期刊文章、参考文献、技术报告、学位论文等全文信息,用于科研教育及其他活动。从而促进科学信息的广泛传播,学术信息的交流与出版,提升科学研究的共利用程度,保障科学信息的长期保存。这是一种新的学术信息交流的方法,作者提交作品不期望得到直接的金钱回报,而是提供这些作品使公众可以在公共网络上利用。

最新的英文文献可以进行查找的网站如下:1、掌桥科研。该平台是由一位资深科研人员带头创办的一站式科研服务平台,是集论文检索、论文下载、文献求助、自然科学基金查询、科研资讯汇总、文献翻译、文档转化为一体的平台。目前拥有近4亿+篇中外文献资源,其外文文献在国内是最为齐全的,分为外文期刊、外文学位、外文会议、外文OA文献、科技报告等均可直接下载,下载时可选择原文+翻译(机译中文)很方便。2、欧洲学位论文库。收录来自欧洲28个国家的563所大学的开放学术资源,论文均可下载。

1、搜索“中国知网”,点击进入中国知网网站。2、在搜索栏中输入自己需要下载的外文文献的主题,点击搜索。3、找到所需要下载的一篇外文文献,单击题目进入。4、进入下图画面,复制该文献的DIO。5、搜索网站SCI-HUB,进入网站在搜索栏粘贴之前复制的DIO,点击“open”。6、这时候你所需要下载的外文文献就会显示在网页中,单击上方的下载箭头,保存其PDF就完成了。扩展资料:知网上能下载的外文文献主要是期刊数据库中的国内出版的英文版期刊和会议数据库中的英文会议论文。还有其他合作的外文数据库springer、Taylor&Francis可以在中文的检索环境下去检索外文,这点对初学者比较适合,但是只能看到题录摘要。对外文文献要求较高、较全,建议你还是根据学科去选择专业的外文数据库查询会比较好。

在哪下载英文文献

心理学英文文献在这里下,网页链接,专门的版块,拿走不谢!

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

去专门的英语文献下载的地方下载啊

当然要去英文文献资源多并且优质的网站,你用seek68文献馆,中外知名数据库整合汇总。

英文文献在哪下载

我给你推荐两个吧,国内网站来说算是最全的了,一个是掌桥科研(有五千多万篇吧,涵盖各学科,可直接获取原文),另一个是INFOMINE学术资源(汇集了大量供高校及研究人员使用的外文文献)

推荐到OA图书馆,可免费下载全文。输入英文关键词即可。

英语论文在哪里下载

进入相关英语学习网站,可以多选择的下载喜欢的。

去专门的英语文献下载的地方下载啊

ProQuest数据库平台 经济、管理期刊全文数据库包括大量学术期刊、学位论文 。Econlit 美国经济学会出版,部分全文 。EBSCO 收录2200种全文期刊,包括经济学、金融、国际商务、管理等SpringerLink 经济、商业与管理电子图书和期刊Elsevier sdos 收录经济类电子图书和期刊Web of Science 综合性检索平台社会科学文献、经济学文献。Scopus 全球最大的文献型数据库。商业、管理和会计,决策科学、经济学、计量经济学和金融学。如果学校的数据库权限不够,或者在校外还可以用seek68文献馆,涵盖的中外数据库更多。

爱学术 网站上每天就可以免费下载一篇文章。各种类型的都有。自己搜索。

在哪儿下载英文文献

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

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