旋转变压器二相法轴角编码原理与实现

旋转变压器二相法轴角编码是一种计算法或查表法。首先利用旋转变压器的二相信号将轴角分为8个区间,而后再利用在小区间的电压直接编码。文中介绍轴角编码的原理及主要电路。

二相法制备聚乙烯醇缩丁醛最佳条件的探讨

叙述了以聚乙烯醇、丁醛为原料在盐酸为催化剂条件下，缩合反应最佳工艺条件的选择．介绍了配方及工艺条件的试验结果．

活性染料二相法印花影响因素的探讨

研究了固色剂用量、糊料类型、过热蒸汽三个因素对活性染料二相法印花的影响。通过在不同固色剂用量下进行固色后测出的K/S值得出,固色剂用量越大,印花的表观色深效果越好。通过对三种不同类型的活性染料分别与海藻酸钠糊和复配糊料混合后印花出的效果作出比较得出,复配糊料印花表观色深随固色时间增加显著提高。通过在过热蒸汽不同固色时间下固色得出,固色的适宜时间为2min。

今日之二相法印花高效蒸化技术(上)

二相法印花技术开发于60年代,近年又有崛起之势。笔者集60年代系统研究和近年来咨询服务之经验,系统地探讨了还原染料的二相法印花、活性染料的二相法印花、涤/棉混纺织物的二相法印花的理论依据、主要因素、典型工艺及相应的高效蒸化技术,并对相关试验作了评价。

织物二相法印花工艺

活性染料直接印花是纤维素纤维织物最常用的印花工艺。这是因为活性染料色谱较广泛、色泽鲜艳、湿牢度较好、印花成本低、适用性强、印花色浆的调配较为方便、花型的丝网印花印制方便及工艺过程控制较为容易。印花后织物不仅手感好，而且各项色彩牢度能达到较高的水平，特别是湿处理牢度和印花匀染性较好。

气相色谱法分析2,6-二异丙基苯酚气相胺化产物

采用气相色谱法 ,HP 35色谱柱分离 ,FID检测器检测 ,以甲醇为溶剂 ,以 2 ,6 二甲基苯胺作为内标物对2 ,6 二异丙基苯酚气相胺化制备 2 ,6 二异丙基苯胺的液相产物进行了定量分析。实验结果表明 ,方法回收率为 97.7%～ 10 8.7% ,相对标准偏差为 0 .5 %～ 5 .0 %。

无约束二次物理气相法CdSe单晶体的生长研究

在物理气相法的基础上,通过无约束二次气相输运法生长出具有自然显露面的尺寸约为6 mm×7 mm×2 mm CdSe晶体。对生长晶体的结构、成分和形貌进行表征,测试发现:XRD粉末衍射图谱强度高无杂峰,CdSe晶体的3个自然显露面分别是(100)、(002)和(110)面,回摆曲线半峰宽度较小;ICP-MS结果显示样品中杂质含量有效降低;红外透过率测试结果显示无约束二次气相法生长的CdSe晶体红外透过率高;SEM观测发现其解理面呈阶梯状且台阶方向一致。结果表明,采用无约束二次气相法生长的CdSe晶体结晶质量较好,纯度高,红外透过率高,并根据BFDH模型分析CdSe晶体自然显露面出现的原因。

基于瞬时无功功率理论的谐波电流检测法

为解决谐波电流检测的长时延问题，依据三相电路的瞬时无功功率理论，采用三相／二相坐标变换法，提出了一种谐波电流实时检测方法．计算结果表明，该方法可以准确、实时地检测出谐波电流，也可替代传统的电力谐波量检测方法．

Comparative analysis of isothermal and non-isothermal solidification of binary alloys using phase-field model

Based on the entropy function, a two-dimensional phase field model of binary alloys was established. Meanwhile, an explicit difference method with uniform grid was adopted to solve the phase field and solute field controlled equations. And the alternating direction implicit(ADI) algorithm for solving temperature field controlled equation was also employed to avoid the restriction of time step. Some characteristics of the Ni-Cu alloy were captured in the process of non-isothermal solidification, and the comparative analysis of the isothermal and the non-isothermal solidification was investigated. The simulation results indicate that the non-isothermal model is favorable to simulate the real solidification process of binary alloys, and when the thermal diffusivity decreases, the non-isothermal phase-field model is gradually consistent with the isothermal phase-field model.

Method for integer ambiguity resolution in GPS network RTK

A method for integer ambiguity resolution in the global positioning system （GPS） multi-reference station network real time kinematic （RTK） is proposed. First, the barycenter of the triangle of reference stations for ambiguity resolution is taken as a reference point. The satellite which has the largest elevation angle with the reference point is selected as a reference satellite. The parameters for constructing the weight matrix of carrier phase observation and the criteria for checking the correctness of integer ambiguity resolution of a network are obtained. Then, the wide ambiguity is calculated by a linear combination method of dualband observation. And the LI ambiguity is obtained by a nonionosphere combination method. The Kalman filter is introduced to refine the floating-point solution of ambiguity and estimate the real-time tropospheric delay. Finally, the cofactor matrix of ambiguity is de-correlated by Z-transformation to reduce the searching space of the integer ambiguity solution and improve the efficiency of the least-squares ambiguity decorrelation adjustment （LAMBDA） algorithm. The experimental results show that this method can reliably obtain the integer ambiguity solution among multi-reference stations with 40 epochs.

本期内容浅析

本期的特色是新工艺新技术较多，适合企业生产运用的实用新技术不少，涉及面较广。我们先从《专论与综述》说起。《活性染料二相法印花影响因素的探讨》作者研究固色剂用量、糊料类型、过热蒸汽三个因素对活性染料二相法印花的影响。研究了二相法印花工艺。

PEG-combined liquid phase synthesis and electrochemical properties of carbon-coated Li_3V_2(PO_4)_3

The carbon-coated monoclinic Li3V2(PO4)3(LVP) cathode materials were successfully synthesized by liquid phase method using PEG as reducing agent and carbon source. The effects of relative molecular mass of PEG on the properties of Li3V2(PO4)3/C were evaluated by X-ray diffraction(XRD), scanning electron microscope(SEM) and electrochemical performance tests. The SEM images show that smaller size particles are obtained by adding larger and smaller PEGs. The electrochemical cycling of Li3V2(PO4)3/C prepared by both PEG200 and PEG20 k has a high initial discharge capacity of 131.1 mA·h/g at 0.1C during 3.0-4.2 V, and delivers a reversible discharge capacity of 123.6 m A·h/g over 30 cycles, which is better than that of other samples. The improvement in electrochemical performance is caused by its improved lithium ion diffusion coefficient for the macroporous morphology, which is verified by cyclic voltammetry(CV) and electrochemical impedance spectroscopy(EIS).

Investigation on Two Novel Substituted β-Cyclodextrins Used as GC Stationary

Aim To study the chromatographic behaviors of two dipentyl cyclodextrin derivative stationary phases. Methods Two new β-cyclodextrin derivatives, heptakis-[2, 6-di-O-pentyl-3-O-(4-nitrobenzyl)] -β-CD and heptakis-[2, 6-di-O-pentyl-3 -O-(5 -hexenyl)]-β-CD, were synthesized and coatal on fed-silica capillary columns. The chromatographic behaviors of the columns were characterized . Results It was found that the she, polarity, and aromatic property of the substituted group at the 3-position of heptakis-(2, 6 - di - O - pentyl) - β - cyclodextrins greatly influenced their chromatographic properties and separation ability. The introduction of aromatic group or a group containing a double-bond may bring π-π interactions between the host and guest molecules, and therefore increases the separation ability of the β-CDs for substituted benzene isomers. Conclusion The new substituted β-CD compounds are very suitable for being used as gas chromatogaphic stationary phases.

基于模糊理论的导弹质量评估

为更好地掌握导弹的质量状态,对基于模糊理论的导弹质量评估进行分析。根据导弹自动化测试系统的测试结果,采用层次分析法对导弹的质量评定体系进行分类,构建导弹质量评估框架。对导弹测试数据的质量等级划分规则进行设计,通过二相Fuzzy统计法,拟合出导弹归一化测试数据属于各个质量状态的隶属函数模型舱,并对导弹各系统以及导弹整体进行了质量综合评定。评估结果验证了该评价体系是合理的。

Morphological evolution and growth kinetics of Kirkendall voids in binary alloy system during deformation process-Phase field crystal simulation study

The formation and growth of Kirkendall voids in a binary alloy system during deformation process were investigated byphase field crystal model.The simulation results show that Kirkendall voids nucleate preferentially at the interface,and the averagesize of the voids increases with both the time and strain rate.There is an obvious coalescence of the voids at a large strain rate whenthe deformation is applied along the interface under both constant and cyclic strain rate conditions.For the cyclic strain rate appliedalong the interface,the growth exponent of Kirkendall voids increases with increasing the strain rate when the strain rate is largerthan1.0×10-6,while it increases initially and then decreases when the strain rate is smaller than9.0×10?7.The growth exponent ofKirkendall voids increases initially and then decreases gradually with increasing the length of cyclic period under a square-waveform constant strain rate.

Measurements of Hydrate Equilibrium Conditions for CH4, CO2, and CH4＋C2H6＋C3H8 in Various Systems by Step-heating Method

Phase equilibrium conditions of gas hydrate in several systems were measured by the step-heating method using the cylindrical transparent sapphire cell device.The experimental data for pure CH4 or CO2+deionized water systems showed good agreement with those in the literatures.This kind of method was then applied to CH4/CO2+sodium dodecyl sulfate(SDS)aqueous solution,CH4/CO2+SDS aqueous solution+silica sand,and(CH4+C2H6+C3H8)gas mixture+SDS aqueous solution systems,where SDS was added to increase the hydrate formation rate without evident influence on the equilibrium conditions.The feasibility and reliability of the step-heating method,especially for porous media systems and gas mixtures systems were determined.The experimental data for CO2+silica sand data shows that the equilibrium pressure will change significantly when the particle size of silica sand is less than 96μm.The formation equilibrium pressure was also measured by the reformation of hydrate.