可以用谷歌学术、sci-hub或者用Science DirectScience Direct收录的期刊是世界上公认的高质量学术期刊,被广泛运用,大部分的高校和研究单位购买的都有该数据库。如果没有可以通过seek68文献馆进入该数据库。
网页链接这个网址里面有免费账号可以在英文数据库Web of Science检索,在这个网址下载
您可以进入爱学术网站,先输入自己要搜索内容的关键词,然后在搜索结果页面选择sci类型即可。
网页链接这个网址里面有免费账号可以在英文数据库Web of Science检索,在这个网址下载
如何下载sci论文,这是一个比较大的内容。1、对于大多数SCI论文而言,都是需要收费才能进行下载的。只有不到10%的可以免费下载。比如pubmed中,对于大多数医学免费期刊,都已经做好链接。highware press是美国斯坦福大学图书馆数据,向全球提供了最大的免费下载平台。2、SCI论文,主要是以数据库的形势进行上市的,由几大数据库商业集团进行经营。如interscience(现已经为welly合并),welly,elseware,也就是我们经常用的其实,这两个数据库,现在已经 能够下载到ISI集团所收录的90%以上的SCI论文。对于非国内北大清华等有名的高校人员,想下载SCI论文,实在比较困难。主要在于可能盲目下载,花没有必要的钱。建议大家可以通过国内目前比较火爆的“派博传思国际中心”等中介机构,进行相关查新服务,比较可取。也可以,通过“科学中华人”等平台,进行SCI论文有效检索后,再进行付费下载服务。这样更为经济。
您可以进入爱学术网站,先输入自己要搜索内容的关键词,然后在搜索结果页面选择sci类型即可。
首先可以到ei和sci检索的数据库下载。其他的可以到中国知网,aps,sciencedirect之类的下载,而且一般在学校,图书馆之类的网站下载是免费的吧。
图书馆:图书馆图书是传统参考文献来源的主要途径,而且相对其他传统方式来说,是比较方便实惠的中国知网:中国知网(CNKI)是比较权威的网络文献来源,而且大多数高校都有跟中国知网的合作,在学校是可以免费下载文献,校外是需要收费的;维普期刊:在维普期刊使用高级检索,可以精确查找到所需文章。网址:万方数据库:网址:百度学术:网址:
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
中国期刊网下载中文文献Web of Science查英文文献,再从全文链接下载
常用的有百度学术,谷歌学术 ,爱学术,暂时只知道爱学术可以批量下载,其它的不清楚。
通常,我们在中国知网,万方,龙源这些数据库搜索和下载参考文献。这些网站对外是收费的,但是,如果你通过学校的图书馆的网络接入,如果你们学校买了版权,就可以免费下载。另外,你也可以在百度学术里面搜索论文,里面,有些文章也是可以免费下载,或者在线观看的。
知网
去学校图书馆里找书籍,另外可以去学校的电子图书馆或者是电子信息室下载一些论文。因为那上面都有一些备注、书名号等等,都可以查的到。还可以自己交钱去学术论坛网或者学术交流中心查阅相关的论文
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搜索“豆瓣2345导航”下载免费ssci苏大。百度 “豆瓣2345导航“, 打开,进入界面。点击下方的 ”sci-hub“, 点击进去。在此界面中的搜索框中输入要下载的文献的名字,点击右侧按钮,即可下载ssci苏大啦。很多时候下载SCI文献是要收费的,这只是其中一个小方法。不是所有都能下载。有一些还要上正规网站下载。