W18Cr4V高速钢离子渗氮层相结构与脆性研究

采用X射线衍射仪,金相显微镜及透射电镜分析W18Cr4V高速钢离子渗氮层相结构,采用连续加载压入法测定渗氮层脆性,分析了渗氮工艺对渗层相结构与脆性的影响。结果表明:离子渗氮工艺影响渗层相结构、含量及其分布,从而影响渗层脆性。     

Synthesis of cylohexanol by three-phase reactive distillation: influence of kinetics on phase equilibria

A reactive distillation process is being suggested for the production of the commercially interesting intermediate cyclohexanol from cyclohexene and water, which avoids some of the drawbacks of the conventional liquid-phase cyclohexane oxidation process, especially with respect to operational safety. This reactive distillation process has its own intricate challenges due to the fact that reaction, distillative separation and liquid-phase splitting occur simultaneously. The interaction of these three phenomena is studied using residue curve maps for both, model simulations and experimental data. Based on the fixed point analysis of the residue curves, a novel process is proposed for the reactive separation of cyclohexene/cyclohexane mixtures which is difficult to be carried out by conventional distillation due to very close boiling temperatures.     

AOT及其复配体系的中相微乳液研究

在表面活性剂－醇－正辛烷－盐水体系中，研究了以双－２－乙基己基磺琥珀酸钠，十六烷基三甲溴化铵及ＡＯＴ与ＣＴＡＢ的复配物为表面活性剂时形成的微乳液性质，考察了ＮａＣｌ浓度、醇的种类与浓度对体系相行为与中相微乳液特性的影响。研究结果表明，ＡＯＴ与ＣＴＡＢ按１：７按摩尔比复配时有显著的协同效应，最佳中相微乳液体积大幅度增加；该体系的最佳含盐量对醇分子碳链长度的变化特别敏感。     

光纤环形延迟线陷波器最佳陷波的实现及PIIN的影响

本文研究了ＰＩＩＮ的时，频响应特性，得到了它作为陷波器的最佳陷波条件，提出了利用环路损耗调节器性能，实现最佳陷波特性的方法，采用该方法使ＦＯＲＤＬ的陷波深度达到了６５ｄＢ，同时，本文还研究限制ＦＯＲＤＬ最佳陷波特性实现的主要系统因素－相位感生的强度噪声（ＰＩＩＮ）给出其在单模条件下的频率特性，由此出发，分析了影响ＰＩＩＮ的几个因素，提出了抑制ＰＩＩＮ的三个途径：（１）采用极化控制器适当调节两个正交     

Calculation of thermodynamic quantities of metals and alloys by statistical moment method

The thermodynamic quantities of metals and alloys are studied using the moment method in the quantum statistical mechanics, going beyond the quasi-harmonic approximations. Including the power moments of the atomic displacements up to the fourth order, the free energy, specific heats C_v and C_p, mean square atomic displacements and thermal lattice expansion coefficients are derived explicitly in terms of the second and fourth order vibrational coupling constants. The thermodynamic quantities are calculated both for cubic (fcc and bcc) and closed packed hexagonal (hcp) metals. The Lennard–Jones type of potentials as well as the effective interatomic potentials derived from the tight-binding (TB) total energy calculation scheme are used. The calculated thermodynamic quantities are favorably compared with the experimental results. For the calculations of alloys, we investigate the effects of thermal lattice vibration on the long range order (LRO) parameter and order–disorder transitions of the ordered binary alloys.     

Monte Carlo simulation of phase separation in iron-based ternary alloys

Numerical simulations of phase separation in Fe–Cr–Mo ternary alloys were performed with use of a model based on the Monte Carlo simulation, in order to investigate mechanisms of phase separation in Fe-based ternary alloys. Cr-rich regions were formed in an Fe–40at.%Cr–5at%Mo alloy. Mo atoms enrich into the Cr-rich region and/or boundaries of Cr/Fe rich regions. Behaviors of Mo and Cr in an Fe 40at.%Mo–5at.%Cr alloy were similar to those in the Fe–40at.%Cr–5at.%Mo alloy. The first peak position of the structure factor moves on to the shorter side of the wave number with the increase of temperature. Analysis of the static structure factor of a minor element indicates that the bifurcation formation of concentration profile of the minor element occurs at peak positions of the major element which is predicted by a theory based on the Cahn-Hilliard equation.     

Practical applications of modified poly(ethylene oxide) networks

Modified poly(ethylene oxide) (PEO) networks have been studied as phase transfer catalysts, flocculates and solvent-free polymer electrolytes. The activity of the hydrogels has been investigated with respect to the structure and crosslinking density of the networks, their degree of quaternization and amphiphilic properties (hydrophilicity coefficients). It has been found that the microenvironment of the active sites (EO segments and ammonium ions) affects the catalytic activity and sorption ability of the modified networks. Hydrophobic organic compounds such as sodium picrate and bromophenolblue are bound predominantly to the lipophilic quaternary ammonium ions. A stable level of electrical conductivity of 5.0×10⁻⁵ S cm⁻¹ was achieved without using of additives. A probable mechanism of ion transport within the networks has been proposed. Potential applications of PEO-based materials as solvent-free solid polymer electrolytes are also discussed.     

光栅投影三维轮廓测量及关键技术分析

说明了光栅投影三维测量技术的原理；就国内外的研究和应用状况，对三维测量中的关键技术，如相位测量，解相位，数据配位和拼接，系统结构的调整和标定等进行了分析综述。     

Local Velocity and Concentration of the Single Components in Water/Oil Mixtures Monitored by Means of MRI Flow Experiments in Steady Tube Flow

In this paper the spatially resolved determination of velocities in two‐phase systems consisting of water and oil by means of nuclear magnetic resonance (NMR) imaging (MRI) techniques is described and applied to steady tube flows with regard to the total flow rate. As MRI offers the possibility to study the flow of multiphase materials spatially resolved with various forms of contrast, even optically opaque water/oil mixtures can be studied in the interior of the material. Besides snapshot images of the actual flow pattern also local velocity and concentration fields of both phases can be obtained separately. The insight into the inner micro flow processes and microstructure allows to characterize fluid mixtures or emulsions. Flow rate and preparation/mixing method were varied in order to realize changes of the flow pattern and the structure of the mixture during flow. Physical models of the flow behavior and physical stability of these complex systems can be based upon this information.     

Si(113)表面的原子结构

利用LEED研究了Si(113)表面的原子结构.清洁表面是采用离子轰击和退火方法制备的.实验发现:当温度高于600℃时表面为1×1结构,随着温度缓慢下降,表面原子结构发生1×1(?)3×1(?)3×2的可逆相变.