一种含硅环氧树脂的制备及固化性能

采用烯丙基缩水甘油醚、四甲基环四硅氧烷为原料,在铂催化剂下进行硅氢加成反应合成了低粘度的有机硅环氧单体.对有机硅环氧单体进行了红外表征,结果显示将环氧基团成功地引入到了化合物中去.以甲基六氢苯酐为交联剂、2-乙基-4-甲基咪唑为促进剂,并采用Kissinger模型对有机硅环氧化合物进行了固化动力学的研究,结果显示有机硅环氧化合物的固化后玻璃化转变温度为200.44℃,5%热失重为347.9℃.     

聚酰胺交联改性氯丁橡胶粘合剂

研究结果表明采用粘流态的低相对分子质量聚酰胺(LMPA)作为交联剂,在常温条件下对氯丁橡胶(CR)类粘合剂作用明显。本文探讨了LMPA的加入量对CR粘合剂180°剥离强度和耐水性能的影响;同时还探讨了该交联型CR粘合剂的改性原理、合成方法以及存储时间。     

中国柳珊瑚化学成分的研究(Ⅵ) Junceella squamata中一个新的多乙酰氧基含氯二萜Junceellin B

从鳞丁心柳珊瑚Janceella squamata中分离出一个新的具有Briarein A骨架的含氯二萜,命名为Junceellin B.它带有四个乙酰氧基,两个双键,一个三元环氧基和一个羟基.分子式C_(28)H_(35)O_(12)Cl,熔点228—230°,比旋光度[α]_D~(25)-13.48°.通过IR,~1HNMR,~(13)CNMR和M_s推导出结构.     

光引发制备互穿聚合物网络及其二阶非线性光学性能

合成了一种含生色团的环氧单体,将它与酚醛缩水甘油醚和双环氧丙烯酸酯及光引发剂溶解在一起后涂膜,用UV光照固化,同时在高压电场下极化,得到了一种极化互穿聚合物网络.该体系二阶非线性光学系数d33值为9.4×10-8esu,d33热稳定性良好.     

2,4,6-哌啶基-1,3,5-均三嗪新的合成方法及结构分析

由二(二甲基胺基二甲硅基)甲基锂1与哌啶腈反应合成了均三嗪2,并通过1HNMR,13CNMR和X-射线单晶衍射等手段进行了表征,结构表明,化合物2属三斜晶系,P-1空间群,a=8.356(3) ,b=9.840(3) ,c=12.019(4) ;α=98.507(4)°,β=101.357(5)°, =108.441(4)°;V=895.4(5) 3,Z=2,R1=0.0734,GOF=0.997.     

Ph2PCH(SiMe3)2的合成及晶体结构分析

由二(三甲基硅基)甲基锂(1)与一氯二苯基膦经一步反应合成了二(三甲基硅基)-二苯基膦基-甲烷化合物(2),并通过1H NMR、13C NMR、元素分析和X-射线单晶衍射等手段进行了表征,结果表明,化合物(2)属三斜晶系,P-1空间群,a=8.815(2)A,b=11.188(3)A,c=11.211(3)A;α=109.864(3)°,β=96.567(3)°,γ=101.867(3)°;V=997.1(4)A3,Z=2,R1=0.0 874,GOF=1.042.     

含氢单晶硅的ESR面效应

电子自旋共振(ESR)实验结果确定:氢气区熔单晶硅的电子自旋总数随样品平均厚度的相对变化不是体效应,而是面效应.面效应的特点是当样品表面与磁场的央角在0°至140°范围内变化时,含氢硅的g 因子保持不变;在O°至±90°范围内ESR 信号强度由大变小,正负转向基本对称.由此推测:Si(H)/Si_2O_2界面中硅悬挂键的数量较少.并观测得:无论红外光照前或后,含氢硅的ESR 信号强度都不随微波功率饱和,并归因于自旋-自旋弛豫时间很小,约T_2=1.4×10~(-(?))秒.     

氟橡胶硫化促进剂2,3,5-三苯基-2H-四唑化氯的合成和配方试验

一、前言氟橡胶具有优异的耐高温、耐介质等性能,因而广泛应用于密封制品上。但氟橡胶也存在几个明显的缺点:压缩永久变形大、低温性能差、高温下机械性能低、加工困难和水蒸汽性能不好等。为了改善26°型氟橡胶的压缩永久变形,国内外曾作了不少工作,主要着眼于从硫化系统方向进行改进。1957年以后26型氟橡胶主要是采用二元胺(1°～4°交联剂),例如目前国     

多孔硅表面Si-OH结构的研究

建立了2×1的表面为Si-OH结构的多孔硅(Porous Silicon,PS)模型,在周期性边界条件下的K空间中,采用基于密度泛函理论广义梯度近似的平面波超软赝势方法,对Si-OH结构进行几何结构与电子结构的计算研究.通过分析优化后稳定的Si-OH结构,从理论上证实多孔硅的结构是完全不规则的,表面结构中两类Si-O键长值分别介于0.161-0.163 nm之间和0.168-0.170 nm之间,两类O-H键长值分别为0.097 nm和0.098-0.100 nm,角∠Si-O-H的值主要分布在109.0°-116.3°之间,角∠O-Si-O的值主要分布在96.2°-98.5°之间;最后通过电子局域函数ELF图分析了表面成键与表面电子分布特性.     

正交叠层板最终拉伸破坏的细观力学研究

基于剪滞理论,研究了在０°方向承受拉伸的复合材料正交叠层板由９０°层的破坏及０°层中部分纤维断裂相互作用所导致的细观应力重新分布．在此基础上,采用随机临界核统计理论,对正交叠层板的最终拉伸破坏进行了细观统计分析．对［０／９０ｎ／０／９０ｎ／０］碳／环氧的计算结果表明,算得的最终拉伸强度能较好地吻合现有的实验结果．     

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.     

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     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the