Some problerns in adsorption and calorimetric studies of the steps of catalytic processes

Principal side factors as well as technical and procedural peculiarities capable of distorting the results of measurements of adsorbed and desorbed amounts, of falsifying the nature of the processes proceeding in the systems under study, and of promoting artifacts in calorimetric and other studies of gas chemisorption on powders are considered. Modified techniques and procedures allowing the elimination of sources of side phenomena and artifacts and freeing traditional glass static adsorption apparatuses and experimental procedures from undesirable factors and peculiarities are proposed. Some available chemisorption and calorimetric data representing artifacts and also some data that are not artifacts but, due to imperfections of chemisorption techniques, show up as artifacts are presented and discussed. Several applications of the improved techniques and procedures to calorimetric and adsorption studies of the steps of catalytic processes proceeding on the basis of natural gas and of products of its pr     

泡沫的稳定性及液晶对它的影响

泡沫体系的表面张力、粘度,表面粘度以及液晶相的存在对泡沫的稳定性皆有影响。消泡剂可改变上述性质。本文报导聚氧乙烯辛基酚(TritonX-100),十二烷基硫酸钠(SDS),油酸三乙醇胺(TEAOL)和卵磷脂等起泡剂在均相溶液及有液晶存在时产生泡沫的稳定性,观察硅油的消泡作用。     

稻麦中FAO模式必需氨基酸与限制氨基酸比值的研究

本文主要介绍稻麦中按FAO模式比必需氨基酸总量与赖氨酸、苏氨酸含量之间比值的推导过程,并获得其比值分别为6.55和9.00。根据比值可推算样品中按模式比的必需氨基酸总量及赖氨酸含量的最佳理论公式。最后还介绍了上述公式的应用举例。该研究内容不仅为提高稻麦中蛋白质的利用率提供理论依据,而且还为强化食品和饲料的营养研究提供简便的计算方法。     

氢氧化铁沉淀分离富集催化极谱法测定铅基合金中硒

探讨了５０μｇ以下的硒与氢氧化铁共沉淀的因素和分离铅基合金中硒的条件，从而成功地利用催化极谱法测定铅基合金中硒。分析范围在０．０５％－０．０００５％，回收率在９１．５％－１０５％间。应用于铅基合金中硒的测定，获得满意的结果。     

增溶甲苯对聚氧乙烯-聚氧丙烯嵌段共聚物胶团的影响

用动态光散射, 测定聚氧乙烯-聚氧丙烯嵌段共聚物水溶液胶团增溶不同量的甲苯后, 其平均流体力学半径R_h的变化, 以及温度对它们的影响。实验结果表明, 25 ℃时胶团水化度高, R_h数值大, 增溶不同量的甲苯对R_h的影响较小。温度升高,胶团的水化度降低, R_h变小, 当温度接近浊点, 水化作用降至最低。因温度升高引起的胶团聚集数增加以及增溶的甲苯进入胶团内部的胀大作用, 使R_h随增溶量增加近于线性的上升。     

A study on organized assemblies in the sodium alkylcarboxylate/fatty alcohol/water systems

The phase behavior and evolution of self-organized assembling structures in the sodium alkylcarboxylate/fatty alcohol systems were investigated by TEM.With increasing concentration of fatty alcohol,the micelles transform into lamellar La phase,sponge L3 phase,multilamellar vesicle,and transfonn back to lamellar La phase.At higher alcohol concentration,a stable two aqueous phase coexisting region has been observed in this kind of systems after aged two months.Unilamellar vesicles were found both in two separated phases but the vesicle density of the upper phase is much higher than that of the bottom phase.     

基于边缘技术的大气激光通信原理研究

介绍了利用边缘技术检测激光频率信号，实现大气激光通讯的原理。描述了利用碘分子滤波器作为边缘滤波器的原理性实验系统，并介绍和分析了实验结果。基于边缘技术的通讯系统拥有很窄的光学带宽和很高的激光频率稳定性，系统的光学信号带宽在400MHz以内，并且接收系统仅对激光信号的频率敏感，可以剔除大气中绝大部分的干扰。对于原理实验的不足之处，文中进行了初步的探讨。     

Thermodynamic properties of cubic ZrC under high pressure from first-principles calculations

The elastic and thermodynamic properties of Zirconium carbide (ZrC) are investigated by ab initio plane-wave pseudopotential density function theory method. The obtained lattice constant, elastic constant and bulk modulus B are consistent with the experimental and theoretical data. Through the quasi-harmonic Debye model, the dependences of the normalized volume V/V ₀ and the bulk modulus B on pressure P, as well as the specific heat C _V on the temperature T are obtained successfully. The relationships of the thermal expansion α with temperature and pressure are also investigated, which indicate the temperature hardly has any effect on the thermal expansion α at high pressure. Supported by the National Natural Science Foundation of China (Grant No. 10776022)     

The influence of impurity on the critical thickness of the CeO_2 buffer layer for coated conductors

The lattice parameters, band structure, density of state and elastic constant of RE-doped CeO2 (RE=Sm, Gd, Dy), the buffer material for coated HTS conductors, are calculated using the plane-wave method with pseudopotentials based on the density functional theory (DFT) of first-principle. The rule and mechanism of the effect of rare earth impurity on the critical thickness of the CeO2 buffer layer are investigated. It is found that, in the range of the calculation, the changes of the lattice volume V and ela...