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101.
对胶体五乳化二锑的研究现状进行了回顾,详细概述了胶体五乳化二锑的各种制备方法及其特点和适用范围,讨论了两种成胶理论。针对目前存在的问题,对胶体五乳化二锑的研究方向及研究重点提出了几点建议。  相似文献   
102.
钨青铜(TB)型晶体材料的分子设计及其新进展   总被引:6,自引:1,他引:5  
在TB型晶体结构讨论的基础上,着重阐述分子设计的方法在TB型晶体材料研究中的具体运用,以及近年来所取得的新进展;指出了国内在TB型晶体材料研究方面与国外存在的差距和今后的努力方向。  相似文献   
103.
Several problems are encountered with asphaltenes during the exploitation, transportation, storage and treatment of crude oil. The purpose of the present work was to study the behaviour of the crude oil fraction (<210°C) by varying the temperature and doping with some hydrocarbons including solid paraffin and aromatic concentrate. The effect of flooding water was investigated. A preliminary characterization study on asphaltenes removed from the crude oil using two different solvents was performed. The state of the oil was determined by the stability factor which indicates the susceptibility of asphaltenes to agglomerate or to disperse in the continuous phase.  相似文献   
104.
智能化劳厄定向法   总被引:1,自引:0,他引:1  
提出了晶体劳厄定向的智能化方法;简述了有关的X射线衍射理论、数学模型和运行步骤;讨论了该方法的可靠性和实用性.  相似文献   
105.
Mixtures of liquid‐crystalline di‐oxetanes and mono‐oxetanes are made for the purpose of making birefringent films by photopolymerization. The composition of a di‐oxetane mixture that forms spin‐coated films of planarly aligned nematic monomers is reported. These films are photopolymerized in air. The molecular order of the monomers can be changed on the microscale to form thin films with alternating birefringent and isotropic parts by using a combination of photopolymerization and heating. The interface observed between the birefringent and isotropic 10 μm × 10 μm domains is very sharp and the films show hardly any surface corrugation. In addition, the polymerized films are thermally stable, making them very suitable for use as patterned thin‐film retarders in high‐performance transflective liquid‐crystal displays (LCDs) which satisfy customer demand for displays that are brighter and thinner and that deliver better optical performance than conventional LCDs with an external non‐patterned retarder.  相似文献   
106.
The effects of α‐form and β‐form nuclei on polymorphic morphology of poly(butylene adipate) (PBA) upon recrystallization from the molten state up to various Tmax values were examined by differential scanning calorimetry (DSC), wide‐angle X‐ray diffraction (WAXD) and polarized light microscopy (PLM). In this study, PBA with complex melting and polymorphism behaviour was used as a model for examining different types and extents of residual nuclei. As the PBA initially containing the sole α‐crystal was brought to a molten state of various Tmax, the extents of trace α‐form crystal nuclei varied and were dependent on Tmax. Furthermore, it did not matter whether, initially, the PBA contained α‐ or β‐form crystals (or both) because only a single type of α‐nuclei could be left upon treatment to the molten liquid state at Tmax. Therefore, only the α‐crystal in PBA had ‘memory capacity’ in the molten liquid state while the β‐crystal did not. This was so because the latter had been completely transformed into the solid state prior to being heated into a liquid. PBA crystallized before α‐nuclei could be packed into α‐crystal, regardless of the crystallization temperature (Tc). For recrystallization from molten PBA without any nuclei, the crystalline polymorphism was correspondingly influenced by Tc. Copyright © 2005 Society of Chemical Industry  相似文献   
107.
Gradient-corrected density functional theory was used to investigate the adsorption of H2S on Pd(1 1 1) surface. Molecular adsorption was found to be stable with H2S binding preferentially at top sites. In addition, the adsorption of other S moieties (SH and S) was investigated. SH and S were found to be preferentially bind at the bridge and fcc sites, respectively. The reaction pathways and energy profiles for H2S decomposition giving rise to adsorbed S and H were determined. Both H2S(ad) → SH(ad) + H(ad) and SH(ad) → S(ad) + H(ad) reactions were found to have low barriers and high exothermicities. This reveals that the decomposition of H2S on Pd(1 1 1) surface is a facile process.  相似文献   
108.
胶溶法合成 TiO_2超微粒子   总被引:1,自引:0,他引:1  
用胶溶法合成了 TiO_2超微粒子。研究了反应物浓度、胶溶剂用量、胶溶温度对胶溶过程的影响,以及表面活性剂 DBS 的量与 Ti 萃取率的关系。探讨了合成超微粒子 TiO_2的最佳条件,分析了产品的特性。200℃热处理得到的产品为非晶型圆球状,粒度均匀,平均6.0nm,在许多有机溶剂中具有良好的分散性和透明性。550℃得到晶态锐钛矿型超微粒子 TiO_2,粒度为8.5nm。700℃热处理得到金红石型TiO_2,粒度为33.2nm。  相似文献   
109.
The application of irradiation in silicon crystal is introduced.The defects caused by irradiation are reviewed and some major ways of studying defects in irradiated silicon are summarized.Furthermore the problems in the investigation of irradiated silicon are discussed as well as its properties.  相似文献   
110.
Makoto Kohga 《含能材料》2006,14(6):471-474
1 IntroductionThe ammonium perchlorate ( AP)-based compositepropellant is currently the most widely used one becausethis propellant has good burning characteristics and me-chanical properties. One of the few serious drawbacks ofthe AP-based propellant is that its products of combus-tion, which include HCl, chlorine, and chlorine oxides,cause atmospheric pollution. Increasing concern for aclean atmosphere in recent years has resulted in a com-pelling need for developing a chlorine-free,enviro…  相似文献   
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