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1.
以环已烷为连续相,丙烯酸作为单体,Span—60为悬浮稳定剂,过硫酸钾为引发剂,N,N’—亚甲基双丙烯酰胺为交联剂,加入不同量的丙烯酸聚氧乙烯酯作为改性剂,利用反相悬浮聚合方法制备耐电解质高吸水性树脂。发现一定比例丙烯酸聚氧乙烯酯的加入,可以明显改善高吸水性树脂的吸水能力和耐盐能力。  相似文献   

2.
N-羟甲基丙烯酰胺在胶乳中作用方式的探析   总被引:2,自引:0,他引:2  
通过萃取、紫外分先先度计等测试分析手段,比较了N—羟甲基丙烯酰胺与丙烯酸酯等乙烯类单体共聚和将N—羟甲基丙烯酰胺与丙烯酸酯类单体分别聚合后共混两种方式得到的胶乳的性能,探讨了N—羟甲基丙烯酰胺在与丙烯酸酯等乙烯类单体聚合中的行为及其在胶乳中的作用方式。  相似文献   

3.
以THF为溶剂,磺胺嘧啶钠为引发剂,甲基丙烯酰氯为封端剂,阴离子聚合合成了一类含双键端基的聚氧乙烯(PEO)大单体;在此基础上,考察了此类大单体与丙烯酰胺、甲基丙烯酸甲酯的自由基共聚反应,合成了一类新型PMMA—PAM—PEO三元共聚物,此物在常温下易于成膜;大单体及共聚物经纯化后,用IR、^1H—NMR、VPO、GPC等进行了表征,证实了产物有预期结构。  相似文献   

4.
用N-(膦酸甲基)甘氨酸与醋酸铜在强酸性和煮沸条件下,合成了铜(Ⅱ)与N-(膦酸甲基)甘氨酸的配合物.经红外光谱、紫外光谱、热谱、磁化率等表征,并用凝固点降低法测定了分子量.结果表明,该配合物是由两个水分子和两个N-(膦酸甲基)甘氨酸中的两个氮原子与铜(Ⅱ)形成的配合物,其化学式为:[Cu(OOCCH2NHCH2PO3H2)2·(H2O)2]·H2O.  相似文献   

5.
阳离子聚丙烯酰胺表征及其阳离子度测定方法   总被引:3,自引:0,他引:3  
采用反相微乳法,合成丙烯酰胺(AM)和甲基丙烯酰氧乙基三甲基氯化铵(DMC)的阳离子聚合物,并采用胶体滴定法测试聚合物的阳离子度,分析了溶液pH值、指示剂用量、滴定速度及残余乳化剂对阳离子度测试准确性的影响,并用红外光谱法确定了聚合物阳离子链节的存在。  相似文献   

6.
降凝剂EVA的结构表征   总被引:1,自引:0,他引:1  
利用^1H-NMR和^13C-NMR对降凝剂乙烯-醋酸乙烯酯(EVA)的分子结构进行了表征,实验表明,在EVA共聚物中乙烯链节(E)、醋酸乙烯酯链节(VA)在聚合链上的序列分布状况主要取决于EVA中醋酸乙烯酯链节含量,具有相同醋酸乙烯酯链节含量的EVA共聚物,分子结构的序列分布状况是相同的.随着醋酸乙烯酯链节含量的增大,VVE的含量和醋酸乙烯酯链节长度增加,而EVE的含量及乙烯链节长度都随着降低.EVA分子结构中的侧链主要是丁基、戊基或更长的烷基.  相似文献   

7.
本文测定了一系列丙烯酸酯(包括:甲基丙烯酸甲酯,甲基丙烯酸异冰片酯,丙烯酸酯等)与N-芳基取代甲基丙烯酰胺,(包括:N-苯基甲基丙烯酰胺(N-φMA),N-对甲苯基甲基丙烯酰胺(N-p-TMA),N-邻甲苯基甲基丙烯酰胺(N-o-TMA),N-对澳苯基甲基丙烯酰胺(N-p-BrPhMA),N-对氯苯基甲基丙烯酰胺(N-p-ClPhMA),N-对硝基苯基甲基丙烯酰胺(N-p-NPhMA),N-邻硝基苯基甲基丙烯酰胺(N-o-NNPhMA),N-萘基甲基丙烯酰胺(N-α-HMA))的共聚物 ̄1H-NMR谱。用 ̄1H-NMR方法测定了共聚物的组成,估算了共聚体系中各单体的竞聚率,比较了各种单体的反应活性。  相似文献   

8.
以N,N’-亚甲基双丙烯酰胺为交联剂,采用溶液聚合法合成丙烯酰胺/N-乙烯基吡咯烷酮共聚物水凝胶.研究了合成条件对水凝胶溶胀度和凝胶强度的影响,并用该水凝胶来浓缩蛋白质稀溶液.  相似文献   

9.
本文就聚氧乙烯十二醇醚、聚氧乙烯十二酸酯、聚氧乙烯十二酰胺三类产物的合成工艺及表面物性作概要论述。  相似文献   

10.
报道了2-丙烯酰胺基-2-甲基丙膦酸的合成方法,并的制备了这一含磷阻垢剂单体,合成路线以五氯化磷出发,在甲苯溶剂中吸收异丁烯后,改进采用二氧化硫脱氯,得到膦酰二氯异构混合物(产率83.3%);膦酰二氯异构混合物经室温水解,得到水解混合物(产率99%),后者再与丙烯腈水在浓硫酸催化下发生加成反应,制得2-丙烯酰胺基-2-甲基丙膦酸这一含磷阻垢剂单体(产率72%),研究比较了不同溶剂、脱氯剂、温度、时间、加成反应中的投料比等对相应产物的影响,并探讨了加成反应的机理,优化结果表明采用二氧化硫脱氯剂的改进路线,可成功制得2-丙烯酰胺基-2-甲基丙膦酸,总产率59%, .优于其他文献报道结果。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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