Characterization of (Y,Gd) BxV1-xO4-x:Eu Phosphor Prepared by Coprecipitation Reaction

White body-color (Y, Gd)BxV1- xO4-x :Eu3 phosphors were prepared by coprecipitation reaction. Under VUV excitation at 147 nm, the red emission colorimetric purity of (Y, Gd)BxV1- xO4-x :Eu3 phosphor is much better than that of commercial PDP (plasma display panels) phosphor (Y, Gd)BO3:Eu3 . But its relative emission intensity is only about 90% of the commercial phosphor.     

热处理工艺对2.25Cr1MoR钢组织和力学性能的影响

本文研究了热处理工艺对2.25C r1M oR钢组织和力学性能的影响。结果表明,该钢在780℃时可获得良好的强韧化效果和较高的抗回火脆性能力,在此基础上得到了该钢板生产制造的热处理工艺参数。实践证明,该工艺合理可行。     

含3-三氟甲基的均三唑并[3,4-b]-1,3,4-噻二唑类化合物的合成

以 3-三氟甲基 - 4-氨基 - 5 -巯基 - 1 ,2 ,4-三唑为原料 ,分别与 2 - ,3- ,4-吡啶甲酸及α-萘乙酸在 POCl3催化下反应 ,制得 4种新的 3-三氟甲基 - 6-取代均三唑并 [3,4- b]- 1 ,3,4-噻二唑( 3a～ 3d) ,并利用 EA,IR,1H NMR等确定了其结构     

iButton技术在安防系统中的应用

本文介绍了一种新型的智能化信息载体iButton以及iButton在安防系统上的应用举例，着重介绍了其硬件、软件设计及工作原理。     

Multi-symplectic methods for the coupled 1D nonlinear Schrödinger system

In the paper, the multi-symplectic formulation of the coupled 1D nonlinear Schrödinger system (CNLS) is considered. For the multi-symplectic formulation, a new six point scheme, which is equivalent to the multi-symplectic Preissman integrator, is derived. We also present numerical experiments, which show that the multi-symplectic scheme has excellent long-time numerical behaviour and energy conservation property.     

叠层材料振动钻削的计算机仿真

以灰色系统理论为基础,将GM(1,h)模型应用于叠层材料变参数振动钻削过程的仿真,运用灰关联度分析方法研究了叠层材料振动钻削过程中的振动频率、振幅、进给量等输入参数对工艺效果的影响,获得了钻削效果影响因素的显著性次序。理论分析和实验结果表明,用GM(1,h)模型进行仿真,建模方便、计算简单。为叠层材料振动钻削研究提供了新的方法和途径。     

新试剂2-(2''''-苯并噻唑偶氮)-1,8-二羟基-3,6-萘二磺酸与钛(Ⅳ)和 CTMAB 形成三元络合物显色反应的研究

在阳离子表面活性剂ＣＴＭＡＢ存在下，２－（２′－苯并噻唑偶氮）－１，８－二羟基－３，６－苯二磺酸与钛（Ⅳ）在ｐＨ３．５～４．５范围内发生高灵敏的显色反应，形成一种蓝色的三元胶束络合物，其最大吸收波长位于６５０ｎｍ，表观摩尔吸光系数ε＝１．２２15;１０５·Ｌ·ｃｍ－１。络合物中钛（Ⅳ）与显色剂的组成比为１：２，钛含量在０～８．０μｇ／２５ｍＬ范围内符从比尔定律。间用于铝合金中微量钛的测定，结果满意。     

The Tb Doping Effect on the Room Temperature Magnetoresistance in(La_(1-x)Tb_x)_(0.67)Sr_(0.33)MnO_3(x≤0.4)

With substitution of La by Tb in (La_(1-x)Tb_x)_(0.67)Sr_(0.33)MnO_3, the room temperature magnetoresistance △R/R_0drops at first, then undergoes an increase near x≈0.1, and finally drops again. The value of room temperaturemagnetoresistance at a field H=12 kOe for (La_(0.9)Tb_(0.1))_(0.67)Sr_(0.33)MnO_3 is -3.56%. The enhancement of the roomtemperature magnetoresistance induced by an appropriate Tb substitution in (La_(1-x)Tb_x)_(0.67)Sr_(0.33)MnO_3 is correlatedwith the shifts of the Curie temperature and metal-insulator temperature to near room temperature. The drop ofthe room temperature magnetoresistance at large Tb doping-contents may be due to its lower T_C and T_(MI) far fromthe room temperature.     

用广义上界算法解大型供应链问题

信息技术和生产率的发展以及全球经济一体化的发展趋势，使供应链成为全世界管理科学的热点.本文在阐述供应链基本数学模型的基础上，系统论述了用改进的广义上界(GUB)算法求解大型供应链问题的计算方法．     

Preparation of Perovskite-Type Oxides La1-x Srx Fe1-y Coy O3 Using EDTA Sol-Gel Method

Two series of perovskite-type oxides with composition La1-xSrxFeO3 (x≤0.8)and La1-xSrxFe1-yCoyO3( x = 0.2；y = 0.2, 0.4 ) powder productions were synthesized by EDTA complexing sol-gel method. The products were characterized by XRD, TEM, SEM, BET method (N2 adsorption)and laser granularity analysis for different synthesis conditions to obtain the optimum conditions for the preparation process. Single-phased, uniform perovskite-type oxides with small particle size were obtained by EDTA sol-gel process with high stability and repeatability,and the process temperature is much lower than that of solid state reaction method.