粘结剂炭的结构与抗氧化性

研究了中间相沥青和酚醛树脂粘结剂及其热解炭的抗氧化性，通过X－ray衍射，扫描电镜，粘结剂残炭率及炭真密度测定，综合评价中间相沥青用作镁炭砖粘结剂的可行性，结果表明，中间相沥青的抗氧化明显优于酚醛树脂，中间相沥青炭结构致密，有取向性，呈石墨化炭结构，而酚醛树脂质炭结构疏松，无取向性，呈难石墨化炭结构，中间相沥青残炭率为65．53％，炭真密度为1．91g/cm^3，酚醛树脂残炭率为49．40％，炭真密度为1．73g/cm^3，可以看出，粘结剂炭的抗氧化性取决于它的显微结构。     

预氧化时间对中间相沥青及其泡沫炭的影响

对AR中间相沥青进行300℃预氧化处理,获得氧化沥青,以AR中间相沥青和氧化沥青为原料制备泡沫炭,采用氮/氧、碳/硫分析仪和热分析仪分析原料的元素含量和热分解过程,采用扫描电子显微镜观察泡沫炭的微观形貌,研究了300℃预氧化处理对AR中间相沥青元素和热重的影响机制.结果表明,AR中间相沥青经300℃预氧化2 h,4 h和6h后,沥青中氧元素含量由原来的0.85%增加到6.60%,10.47%和11.31%.AR中间相沥青经预氧化后获得了孔径较小的泡沫炭材料.当预氧化时间为6 h时,炭化和石墨化泡沫炭的压缩强度分别为12.07 MPa和9.06 MPa.     

酚醛树脂保温板热解动力学研究

采用热重分析仪研究酚醛树脂保温板粉体热解行为.采用FWO法探讨活化能分布,机理函数法确定热解动力学模型.结果表明:10 K/min的升温速率下,酚醛树脂保温板粉体热解过程可分为三个阶段.低于180℃,粉体表面吸附水份受热脱附蒸发过程,失重约10％,符合一维扩散的D1机理函数模型,活化能约25 kJ/mol;180～408℃,交联网络的分解和主聚合物链的随机断裂,同时释放出低分子烃类挥发物,失重约32％,符合二级化学反应模型,活化能约为58 kJ/mol;408～800℃,芳香族组分分解,失重约28％,遵循三维扩散、球形对称模型,活化能约为67 kJ/mol;剩余固体物为炭,约占30％.DTG曲线出现多峰,证明酚醛树脂保温板热解是个复杂过程;随着升温速率提高炭得率略有增加.     

攀枝花铁精矿粉氧化过程的实验研究

采用热重分析法研究升温速率和反应气流量对铁精粉氧化过程的影响。采用积分法对不同气体流量条件下的热重数据进行处理得到反应的动力学参数(表观活化能E)。研究结果表明:升温速率和气体流量均能改变氧化产物的微观形貌;在整个氧化反应过程中,主要步骤由外扩散型转变为内扩散型,最后转变为外扩散型;220~350℃时,表观活化能为48~52 kJ/mol;400~600℃时,表观活化能为22~30 kJ/mol;620~750℃时,表观活化能为11~15 kJ/mol;当升温速率8℃/min时,反应的最佳气流量为45 mL/min。     

钼酚醛树脂热分解动力学的研究

用热重法TG分析了钼酚醛树脂的热分解动力学。实验结果表明：固化剂六亚甲基四胺与钼酚醛树脂配比为10／100时，钼酚醛树脂的热失重率最低，同时热分解温度最高；钼酚醛树脂的热分解反应为一级反应，热分解活化能为137．5kJ／mol，500℃时热分解速率常数为9．83^＊10^4s^-1。     

中间相沥青原料对泡沫炭结构及性能的影响

考察了萘系和煤系中间相沥青原料对发泡工艺及石墨化泡沫炭结构及性能的影响.由于萘系中间相沥青比煤系中间相沥青的平均相对分子量低且分布宽,两者的最佳发泡条件分别为600℃/5 MPa、600℃/1.5 MPa.流线型域状结构及圆盘状分子结构的煤系中间相沥青易于得到高热导率、高压缩强度的泡沫炭,所制煤系中间相沥青泡沫炭的热导率和压缩强度分别为33.4 W/(m·K)、1.28 MPa.     

基于热重质谱联用的沥青质燃烧特性分析

为了分析沥青质的燃烧特性,利用热重质谱联用技术模拟了沥青质在空气环境中的燃烧.分别采用Coats-Redfern积分法和分布活化能模型计算了沥青质不同阶段的活化能,其中CoatsRedfern积分法将沥青质的燃烧过程分为2个阶段,其活化能分别为221.33和147.07 kJ/mol.采用分布活化能模型计算了转化率为0.1~0.9的9个活化能,活化能从210.49 kJ/mol逐渐降低至42.98 kJ/mol.根据质谱图,确定了各个时刻逸出气体的种类和产量.2种活化能计算方法分别验证了沥青质燃烧过程中活化能逐渐降低,说明在燃烧过程中随着反应的进行,燃烧逐渐变得更容易发生.由质谱图与沥青质的热失重速率曲线比较可知,热失重速率峰值处气体逸出量最多.     

微波对Fenton试剂降解苯酚反应活化能的影响

研究了在微波场条件下Fenton试剂降解含酚废水的反应．分别在常规和微波场条件下进行反应,测定了反应动力学曲线,发现在常规条件下和微波条件下,反应动力学曲线可分成两个阶段,第一阶段为二级反应,第二阶段为一级反应;讨论了温度、微波功率对总有机碳（TOC）去除率的影响,估算了反应活化能．实验结果表明：微波辐射可提高Fenton试剂降解苯酚的反应速率和TOC去除率,降低反应活化能;当微波功率分别为100、200和600W时,在反应的第一阶段,苯酚降解反应活化能分别为9．833、9．139和8．579kJ／mol,在第二阶段分别为28．245、27．560和26．710kJ／mol,低于常规条件下相应阶段的苯酚降解反应的活化能（第一阶段为10．782kJ／mol,第二阶段为30．294kJ／mol）,且反应活化能随着微波强度的增大而减小．     

苯热解渗透炭抑制焦炭劣化反应动力学

进行苯热解渗透炭抑制焦炭劣化反应动力学实验,用未反应收缩核模型表征动力学实验数据,建立苯热解渗透炭抑制焦炭劣化反应动力学模型,确定模型参数.依所建动力学模型,计算出抑制焦炭劣化反应过程中的相对外扩散阻力ηg/Ση、相对内扩散阻力ηD/∑η和相对界面反应阻力ηC/∑η.研究结果表明:按Arrhenius方程得到苯热解渗透炭抑制焦炭劣化反应的活化能Ea=217.0 kJ/mol和有效扩散活化能ED=162.9 kJ/mol,均大于空白焦炭劣化反应的活化能Ea-142.0 kJ/mol和有效扩散活化能ED=96.30 kJ/mol;苯热解炭抑制焦炭劣化反应起始阶段主要受界面化学反应和外扩散影响,随着反应进行,劣化反应由内扩散、界面化学反应和外扩散同时影响;在较低温度下,焦炭劣化反应主要受界面化学反应控制,随反应温度升高,界面化学反应的相对阻力逐渐下降.     

中间相沥青用作镁炭砖粘结剂的可行性研究

提出以中间相沥青替代酚醛树脂作镁炭砖粘剂来提高镁炭砖的质量。通过正交实验选定了用作粘结剂的中间相沥青，并探讨了中间相沥青溶剂分级组分对镁炭砖型块耐压强度的影响。两种粘结对比实验表明，中间相沥青结合型块的高温耐压性能优于酚醛树脂结合型块。上述实验结果具有一致性。     

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