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101.
本文介绍了以X-射线衍射法测定非品区结构的径向分市函数RDF方法,并将其应用于聚苯乙烯(PS)非晶区的结构研究.  相似文献   
102.
对新型的代铬刷镀层Ni-Fe-W-P-S进行了耐腐蚀性能机理的分析研究。用扫描电镜(SEM)、透射电镜(TEM)、扫描隧道显微镜(STM)、X射线衍射及电子能谱(XPS)等的分析表明,基体组织为非品结构是代铬刷镀层优异耐腐蚀性的主要原因.  相似文献   
103.
本文报道用光电二极管阵列检测器(PAD)鉴定小蔓和大蔓长春花中的长春胺。并对经典制备方法得到的长春胺样品进行了纯度判断。利用建立的紫外光谱数据库对长春胺中的分解产物进行光谱检索和鉴定。测定了长春胺的稳定性。  相似文献   
104.
By use of salt elimination, the transition metal substituted oligosilanes (η5-C5Me4Et)Fe(CO)2SiMe2SiMe2Cl 1, (η5-C5Me4Et)Mo(CO)3SiMe2SiMe2Br 2, (η5-C5Me4Et)Fe(CO)2(SiMe2)6(CO)2Fe(η5-C5Me4Et) 3 and (η5-C5Me4Et)Fe(CO)2(SiMe2)6Br 4 were prepared and characterized. Compound 1 is well crystallized from pentane and its structure has been determined by X-ray diffraction analysis.  相似文献   
105.
氢火焰离子化检测器校正因子的理论计算   总被引:8,自引:0,他引:8  
根据FID检测器工作原理,提出一种相对质量校正因子的计算公式。由该公式出发可以推导出相对摩尔响应值(RMR)与化合物碳数的线性关系式和有效碳数的近似计算方法,并赋予原计算方法中的参数以明确的含意,解决了参数之间的矛盾。新方法的计算值同文献数据吻合良好。  相似文献   
106.
The new lithium ionic conductors, thio-LISICON (LIthium SuperIonic CONductor), were found in the ternary Li2S-SiS2-Al2S3 and Li2S-SiS2-P2S5 systems. Their structures of new materials, Li4+xSi1−xAlxS4 and Li4−xSi1−xPxS4 were determined by X-ray Rietveld analysis, and the electric and electrochemical properties were studied by electronic conductivity, ac conductivity and cyclic voltammogram measurements. The structure of the host material, Li4SiS4 is related to the γ-Li3PO4-type structure, and when the Li+ interstitials or Li+ vacancies were created by the partial substitutions of Al3+ or P5+ for Si4+, large increases in conductivity occur. The solid solution member x=0.6 in Li4−xSi1−xPxS4 showed high conductivity of 6.4×10-4 S cm−1 at 27°C with negligible electronic conductivity. The new solid solution, Li4−xSi1−xPxS4, also has high electrochemical stability up to ∼5 V vs Li at room temperature. All-solid-state lithium cells were investigated using the Li3.4Si0.4P0.6S4 electrolyte, LiCoO2 cathode and In anode.  相似文献   
107.
An analysis of the crystallization behaviour of a new poly(aryl-ether-ether-ketone-ketone), PK99, by differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD) is presented. Isothermal crystallization TG were obtained in the whole range between the glass transition temperature (T g) and the melting temperature (T m) as a consequence of the slow crystallization kinetics stemming from the closeness of these transitions. The calorimetric results, compared with WAXD data, were applied to determine the theoretical melting temperature and crystallization enthalpy. The DSC and WAXD data were combined in order to calculate the total amount of the crystallizable fraction of the polymer, and a model was proposed to explain the difference between the fractions of crystallinity observed with these techniques. The thermal and X-ray data were also correlated with different lamellar morphologies arising from the crystallization conditions. Finally, DSC experiments on the crystallized sample were used to detect the presence of a rigid amorphous phase which does not relax at T g. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
108.
An original system which uses Porous Graphitic Carbon as support and a mixture of organic solvents as mobile phase is proposed for the analysis of triterpenic acids by liquid chromatography. The separation of betulinic acid, ursolic acid, oleanolic acid, and 18alpha- and 18beta-glycyrrhetinic acids was carried out within a short time and monitored by evaporative light scattering detection as universal detection method. Molecular modelling studies show that the main contribution to the selectivity comes from the electrostatic interaction characterised by the dipole moment of the products.  相似文献   
109.
A new approach to calculating the equilibrium characteristics of the adsorption of noble gases on the amorphous surfaces of adsorbents was developed and applied to the Ar−TiO2(rutile) system. Intermolecular adsorbate-adsorbate interactions are taken into account for the nearest neighbors in the quasi-chemical approximation. The lattice energy parameters of all interactions of the model are determined from the Lennard-Jones potential (12-6). The formation of amorphous TiO2(rutile) surface includes completion of the surface layers and partial removal of the surface oxygen ions. The quality of the amorphization procedure was confirmed by the experimentally measured heats and isotherms of adsorption of the system under study. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1109–1118, June, 1997.  相似文献   
110.
A heated injection system for a microprocessor-controlled GC has been developed for the (GC)2 analysis of the volatile phase of whole smoke of a cigarette. Effects of injection port temperature and the presence of a Cambridge filter pad are demonstrated. Chromatograms are shown for smoke samples with and without a Cambridge Filter with the sample valve oven at 25°, 165° and 205°C. The use of a flame ionization and a nitrogen-phosphorous detector is illustrated.  相似文献   
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