SCDF法对VPO催化剂物性的影响

以两种不同方法制备ＶＰＯ催化剂,分别采用超临界流体干燥法（ＳＣＦＤ）,常规见干燥法干燥。使用ＢＥＴ,ＸＲＤ等测试手段,考察了催化剂在４００℃下焙烧后的粒子比表面积的大小和晶相组成。实验结果表明：采用超临界流体法比采用常规干燥法所制得催化剂的比表面积明显增加,且对催化剂的晶相组成也有一定的影响。     

超临界流体干燥对VPO催化剂比表面和晶相的影响

以V2O5、浓H3PO4为原料，浓HCl和柠檬酸作还原剂，加入一定含量不同金属离子作助剂，采用超临界流体干燥法制备了VPO催化剂，并在不同气氛下进行活化，应用BET、XRD表征手段，考察了各VPO催化剂粒子的比表面积、晶相结构。实验表明：采用超临界流体干燥法可使催化剂的比表面积显增加，助剂的种类和量不同、活化气氛不同、对催化剂比表面积的影响也不同，助剂的种类对催化剂的晶相结构也有一定的影响。     

复合助剂对VPO催化剂物性的影响

以V2O3、浓H3PO4为原料,浓Hcl和柠檬酸作还原剂,加入一定含量不同金属离子作为助剂采用超临界流体干澡法制备了VPO催化剂,并在不同气氛下进行活化．应用BET、XRD、XPS等表征手段,考察了各VPO催化剂粒子的比表面积、晶相结构及表面V离子价态等物性．实验表明：采用超临界流体干燥法可使催化剂的比表面积显著增加,助剂的种类和量不同,活化气氛不同,对催化剂比表面积的影响也不同,助剂的种类对催化剂的晶相结构也有一定的影响．但对催化剂表面V离子价态影响不大．     

复合助剂对VPO催化剂物性的影响

以Ｖ２Ｏ５、浓Ｈ３ＰＯ４为原料,浓Ｈｃｌ和柠檬酸作还原则,加入一定含量不同金属离子作为助剂采用超临界流体干燥法制备了ＶＰＯ催化剂,并在不同气氛下进行活化,应用ＢＥＴ、ＸＲＤ、ＸＰＳ等表征手段,考虑了各ＶＰＯ催化剂粒子的比表面积,晶相结构及表面Ｖ离子价态特特性。     

制备化学对钒磷氧催化剂物理性质影响的考察——I.溶胶—凝胶法及常规制备法

应用 Ｂ Ｅ Ｔ、 Ｘ Ｒ Ｄ、 Ｔ Ｅ Ｍ 等手段研究了由溶胶—凝胶法及常规制备法制备的钒磷氧催化剂的比表面积,晶相组成,晶粒大小等物理性质．发现制备化学因素对钒磷氧催化剂物理特性的影响比较复杂,尤其是不同方法之间所表现出的差异比较明显．由有机相中制备时可以获得单一 Ｂ 相,且晶相组成与晶粒尺寸受制备条件的影响相对较小．实验结果表明包括溶胶—凝胶法在内的几种制备方法制得的催化剂粒子较大,分布不均,且比表面积较小．通过本研究提出了制备大比表面积小粒子 Ｖ Ｐ Ｏ 催化剂的其它可能途径．     

制备化学对钒磷氧催化剂物理性质影响的考察——Ⅰ．溶胶—凝胶法及常规制备法

应用ＢＥＴ、ＴＥＭ等手段了由溶胶－凝胶法及常规制备法制备的钒磷氧催化剂的比表面,晶相组成,晶粒大小等物理性质,发现制备化学因素对钒磷氧催化剂物理特性的影响比较复杂,尤其是不同方法之间所表现出的差异比较明显,由有机相中制备时可以获得单一－Ｂ相,且晶相组成与晶粒尺寸受制备条件的影响相对较小,实验结果表明包括溶胶－凝胶法在内的几处制备方法制得的催化剂粒子较大,分布不均,且比表面积较小,通过本研究提出了制     

Ce—Mo复合氧化物的制备和表征

采用溶胶－凝胶法（Ｓｏｌ－ｇｅｌ）制备出Ｃｅ－Ｍｏ复合氧化物催化剂。并用ＤＴＡ－ＴＧ,ＸＲＤ,ＢＥＴ等测试手段,考察了制备条件对Ｃｅ－Ｍｏ复合氧化物的比表面积,晶相结构等性质的影响。     

超细氧化铝的制备及表征

以硝酸铝为原料、柠檬酸作配体、聚乙二醇(PEG)水溶液作分散剂,采用溶胶凝胶以及超临界干燥法制备了氧化铝超细粒子。采用比表面测试、透射电镜等分析手段对超细粒子的形貌、粒径、粒子分布以及比表面和孔分布等进行了研究,考察了干燥方法对氧化铝颗粒大小、比表面积和孔分布的影响。结果表明,超临界干燥方法制备的氧化铝为长100nm、直径10nm左右的高比表面纤维状超细粒子,粒子分布均匀,焙烧后不团聚。作为催化剂的载体,超细氧化铝粒子负载的Co Mo催化剂的HDS活性略高于普通干燥法制备的氧化铝负载的Co Mo加氢脱硫催化剂。     

红外干燥在溶胶-凝胶法制备纳米TiO2中的应用

在溶胶-凝胶法制备纳米TiO2的过程中,分别采用红外干燥（IFD）和超临界流体干燥（SCFD）技术对生成的凝胶进行干燥,采用XRD、SEM、BET对样品进行表征．测试结果表明,两种干燥方法制备的样品在形貌、晶相、晶粒大小等方面一致．但利用红外辐射技术干燥纳米TiO2可以简化制备步骤、缩短干燥时间、降低生产成本,优于SCFD技术．     

正丁胺对Tio2／Sio2气凝胶光催化活性的影响

用溶胶 -凝胶法、超临界干燥技术合成了不同组成的TiO2 /SiO2 气凝胶材料 ,通过模板剂正丁胺调变其孔结构和孔分布 ,利用N2 吸附法、X -射线衍射法和激光拉曼光谱表征了气凝胶的比表面积、孔分布、晶相结构以及TiO2 的分散状态 .用流动法考察了在TiO2 /SiO2 气凝胶上CO光催化氧化反应的活性 ,并讨论了结构调变对提高催化活性的影响 .     

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