功能化聚苯乙烯树脂负载钯催化剂在聚酮合成中的应用

采用苯乙烯与二乙烯基苯交联合成聚苯乙烯树脂微球,通过一系列反应后得到表面接枝双齿氮的功能化树脂微球.以负载有乙酸钯的功能化树脂微球组成的催化体系催化一氧化碳和苯乙烯共聚合成聚酮.利用红外光谱和扫描电镜对树脂负载催化剂及聚合产物进行了表征.研究了催化体系中各组分用量及反应时间对共聚反应的影响.结果表明,树脂负载催化剂对聚酮合成反应具有较好的催化性能:当树脂用量为0.5 g、乙酸钯为22.4 mg时,聚酮产量达8.6606 g.     

离子液体作用下CO与苯乙烯的交替共聚反应

在室温离子液体1-丁基-3-甲基咪唑四氟硼酸盐的作用下,利用2,2′-联吡啶、氟硼酸和乙酸钯组成复配催化体系催化一氧化碳和苯乙烯共聚,合成了聚(1-氧代-2-苯基丙撑).利用元素分析、示差扫描量热、热质量分析及红外光谱等方法对共聚产物进行了表征.同时,考察了钯复配催化剂在离子液体中对一氧化碳和苯乙烯交替共聚的重复性,使用4次后钯复配催化剂仍有催化活性.通过对比发现在聚合过程中钯复配催化剂的催化效果明显优于加入2,2′-联吡啶和乙酸钯二者混合物的催化效果.分析了离子液体的用量对催化活性的影响,在最优条件下钯复配催化剂对一氧化碳和苯乙烯交替共聚的催化活性可达3.49×103g/(mol.h).     

一氧化碳与苯乙烯溶液聚合反应研究

邻氯苯酚作为溶剂,乙酸钯／对甲苯磺酸酮和2,2′,－联吡啶组成的催化体系催化苯乙烯和一氧化碳的溶液共聚反应,合成出特种高分子材料聚酮－聚（1－氧代－2－苯基丙撑）。研究了铜盐种类、对甲苯磺酸铜用量、甲醇用量、溶剂用量、苯乙烯量及强酸种类等对该共聚反应的催化活性的影响。结果表明,溶液聚合的产物聚酮为一氧化碳与苯乙烯的交替共聚物,溶液聚合反应的催化活性高于沉淀聚合,对甲苯磺酸铜具有助催化作用。     

聚苯乙烯负载钯催化剂在共聚反应中的失活原因

对比分析聚苯乙烯负载钯催化剂在使用前后的结构变化,以图找出其催化共聚活性降低的原因; 制备了聚苯乙烯负载钯催化剂(PS-phen/Pd(OAc)2和PS-phen/PdCl2),并成功将其用于催化苯乙烯与CO的共聚反应.在温度为65 ℃,CO压力为3.0 MPa,反应5 h的条件下,PS-phen/Pd(OAc)2和PS-phen/PdCl2的催化活性分别为1.02×104和5.50×103 gPK/molPd·h,当循环使用3次后,催化活性分别降低至570 和97.4 gPK/molPd·h.对于新制负载催化剂与使用3次后回收的负载催化剂, 分别进行了元素分析、原子吸收光谱、傅立叶变换红外光谱、热重分析和场发射扫描电镜等表征.结果表明 催化剂中钯的流失和N-H键的不稳定性可能是导致催化活性降低的主要原因.     

Ni(Ⅱ)/PNP催化体系催化乙烯齐聚的研究

合成了3种PNP配体,与Ni(Ⅱ)形成催化剂,在助催化剂甲基铝氧烷(MAO)存在的条件下,催化乙烯齐聚.试验结果表明:镍系催化剂催化活性最高可达4.65×105g/(mol.h),α-烯烃选择性达76.40%.利用核磁共振氢谱、元素分析及质谱对配体及催化剂进行了结构表征.     

CuCl/bpy催化的苯乙烯原子转移自由基悬浮聚合

以1-苯基氯乙烷(1-PEC l)为引发剂、氯化亚铜(CuC l)为催化剂、2,2′-联吡啶(bpy)为配体,采用开放体系,在外加搅拌和氮气保护下,研究了苯乙烯的悬浮法原子转移自由基聚合(ATRP),采用分散相水中加入电解质N aC l的方法抑制催化剂配合物向水相的扩散.结果表明,所得聚合物的分子量随转化率呈线性增加,分子量分布较窄(分布指数可达1.40),聚合反应对单体浓度为一级动力学关系,经计算聚合体系的活性自由基浓度为6.89×1-0 8m o l/L;而对A IBN为引发剂时该催化体系的反相ATRP悬浮聚合研究显示,聚合反应可控性很差,原因在于CuC l2的水溶性太强.     

双金属络合催化剂中心金属对环氧丙烷/二氧化碳共聚影响

合成了一系列基于Zna[M(CN)b]c(M=Fe2 ,Cr3 ,Ni2 ,Co3 ,Mn3 ,Mo4 ,Cd2 和Fe3 )的双金属络合催化剂,并且用于催化环氧丙烷和二氧化碳的共聚反应,以研究中心金属对催化剂催化性能的影响。实验结果表明中心金属对催化剂催化性能影响很大,其中以Co3 ,Ni2 为中心金属的催化剂具有较高的催化效能,分别达到2000和482g/g,而以Cd2 ,Mn3 为中心金属的催化剂几乎没有催化活性。以Co3 ,Ni2 ,Fe3 为中心金属的催化剂能得到x(CO2)大于0.3的共聚物,而其它催化剂的共聚产物的x(CO2)小于0.1。     

双金属络合催化剂中心金属对环氧丙烷／二氧化碳共聚影响

合成了一系列基于Zna [ M （CN） b ] c （ M = Fe^2＋ , Cr^3＋ , Ni^2 ＋ , Co^3＋ , Mn^3＋ , Mo^4＋, Cd^2＋ 和 Fe^3＋） 的双金属络合催化剂，并且用于催化环氧丙烷和二氧化碳的共聚反应，以研究中心金属对催化剂催化性能的影响。实验结果表明中心金属对催化剂催化性能影响很大，其中以Co^3＋，Ni^2＋为中心金属的催化剂具有较高的催化效能，分别达到2000和482g／g，而以Cd^2＋,Mn^3＋为中心金属的催化剂几乎没有催化活性。以Co^3＋，Ni^2＋,Fe^3＋为中心金属的催化剂能得到x（CO2）大于0．3的共聚物，而其它催化剂的共聚产物的x（CO2）小于0．1。     

双官能化的环戊二烯基钛/锆络合物的合成及催化乙烯与1-己烯的共聚

合成了一系列含有烯丙基和芳基的茂金属络合物,通过核磁共振氢谱(~1H-NMR)、核磁共振碳谱(~(13)C-NMR)、质谱(MS)和元素分析(EA)表征,确认了其化学组成,在甲基铝氧烷(MAO)助催化下,这些茂金属络合物有效催化乙烯聚合以及乙烯与1-己烯共聚,在50℃、1.0 MPa时,催化活性最高达到520 kg/(mol·h)。研究结果表明,烯丙基的引入稳定了催化活性中心,使得聚合反应能够在较高温度下进行,芳基的引入提高了该类络合物的共聚能力。同时还研究了聚合温度、助催化剂比例等因素对聚合反应的影响,结果表明,随着聚合温度升高催化活性先升高后降低,80℃时活性最高,为352 kg/(mol·h);含有双官能团的茂金属催化活性随着助催化剂比例升高而升高,聚合物分子量随着助催化剂比例升高而降低;1-己烯插入率最高可达4.30%,这表明双官能化茂金属有效提高了双配体茂金属共聚能力。     

5-位含偶氮功能基团的降冰片烯衍生物合成及加成聚合

合成了5-位含偶氮苯功能基团的降冰片烯衍生物,并以双-(β-酮萘胺)镍(II)为主催化剂,三五氟苯硼(B(C6F5)3)为助催化剂,在甲苯中对该单体进行了加成均聚合与共聚合研究;采用FT-IR、1H NMR、13C NMR、UV-Vis、GPC、TGA对合成单体及聚合产物进行了表征。结果表明,合成单体及聚合产物均在300-400nm范围具有较强的光学吸收;共聚物的分子量在4.78×104 g/mol到5.15×104 g/mol之间,均聚物的分子量在6.5×105 g/mol到1.28×106 g/mol之间;聚合产物的热稳定性可达到320 °C以上,且在普通有机溶剂中具有良好的溶解性。     

Markedness and its Interpretation in Language Use

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.     

Features of Women's language

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

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.     

Lower Paleozoic oil relationships within Williston Basin, Canada

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.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

Design and analysis of generic LBS application developing platform

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.     

Achieving Unusual States of Matter Under High Pressure

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-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

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-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

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