绿色荧光粉YAGG∶Tb,Gd用于FED的尝试

FED器件的发展迫切需要具有化学和热稳定性 ,高亮度 ,长寿命的新型荧光材料。本文合成了Gd3 +离子共掺杂的YAGG∶Tb获得了YAGG∶Tb ,Gd ,并将其用于 0～ 30 0 0V低压范围 ,对其在不同电压和电流密度下的发光特性进行了测试。结果表明 ,该种材料特性优于ZnO∶Zn并且不存在电压与电流饱和     

张金磊：向支气管哮喘宣战的勇士

支气管哮喘是一种常见病、多发病、疑难病,多自幼发病,以反复出现咳痰、哮喘、呼吸困难为主症,严重影响着患者的身心健康。据流行病学统计,我国哮喘病率1～4%,约有4800万患者,其中儿童约占62.6%。有关专家预     

异型扬声器纸盆几何形状数学模型的设计

构造了椭圆形和跑道形两类扬声器纸盆的数学模型．从理论上证明这两类数学模型的光滑性．给出了生成这两类模型的步骤，为开发、生产扬声器纸盆模具获得新的依据，对扬声器外形随意变化提供很大方便．该方法已经在计算机上模拟出三维图形，通过实验得到证实．     

Rogue Waves for a (2+1)-Dimensional Coupled Nonlinear Schr?dinger System with Variable Coefficients in a Graded-Index Waveguide

Studied in this paper is a(2+1)-dimensional coupled nonlinear Schr?dinger system with variable coefficients,which describes the propagation of an optical beam inside the two-dimensional graded-index waveguide amplifier with the polarization effects. According to the similarity transformation, we derive the type-Ⅰ and type-Ⅱ rogue-wave solutions. We graphically present two types of the rouge wave and discuss the influence of the diffraction parameter on the rogue waves.When the diffraction parameters are exponentially-growing-periodic, exponential, linear and quadratic parameters, we obtain the periodic rogue wave and composite rogue waves respectively.     

Yb2O3-Y2O3-Gd2O3-ZrO2热障涂层制备及性能研究

以Yb2O3、Y2O3 、Gd2O3稀土氧化物粉末和ZrOCl2·8H2O粉末为原料,采用化学共沉淀法制备了Yb2O3-Y2O3-Gd2O3-ZrO2 (YYGZO)热喷涂用粉末,采用大气等离子喷涂技术制备了YYGZO涂层,利用场发射扫描电镜(FESEM)、X射线衍射(XRD)研究了YYGZO粉末及涂层的微观组织形貌、相结构.结果表明,制备的热喷涂YYGZO粉末大部分呈规则实心球体状,且球形度良好,颗粒粒径均匀,大部分颗粒粒径分布为30～60μm,流动性能较好,满足大气等离子喷涂的要求.YYGZO涂层具有较好的高温相结构稳定性.所制备YYGZO热障涂层组织结构比较致密,涂层各个界面结合紧密,孔隙率约为9.23;,结合强度为35.2 MPa.     

热镀铝锌轴套及轴瓦失效机理分析

对热镀铝锌过程中的沉没辊轴套及轴瓦进行了失效分析,采用扫描电镜和能谱仪对其微观组织形貌进行观察。结果表明轴套及轴瓦的失效过程是腐蚀、磨损协同作用的结果;Fe_2Al_5硬质颗粒磨损是失效过程中的主要摩擦形式;轴套为3层结构,内层为Fe基合金,中间层为过渡层,外层为Co基合金。外层中Co基固溶体容易熔融腐蚀,同时laves相的磨粒磨损消耗,造成轴套尺寸显著降低;轴瓦为Fe基合金,腐蚀失效后内部形成了孔蚀、裂纹和组织疏松。     

智能多功能报警系统的研制

本文介绍了一种新型多功能报警系统,它实现了全方位立体空间的安全监控,功能齐全,应用广泛,既能对温度,烟雾等多项指标进行监控报警,又可根据需要灵活切除．可用于家庭,商店,部队等场所,有着良好的市场前景．     

Internet 网与管理信息系统

随着Ｉｎｔｅｒｎｅｔ网在我国的广泛开通和网络用户的迅猛增长,如何在Ｉｎｔｅｒｎｅｔ网上建立大型管理信息系统正在引起人们的关注．本文概述了建立大型管理信息系统所需要的系统环境,Ｉｎｔｅｒｎｅｔ网上管理信息系统的几个特点,建立管理信息系统所要解决的关键问题等内容．指出：在Ｉｎｔｅｒｎｅｔ网上建立管理信息系统是今后管理信息系统发展的必然趋势．     

“波适康”给您带来生命之光——“波适康”红外养生暖毯简介

前不久,北京华讯智慧科技发展有限公司向国内市场推出一款名为“波适康”红外养生暖毯的保健用品。波适康毯是一种建立在现代高分子材料学、现代物理学、现代生物学基础上研究开发出的高科技产品。     

Lax pair and vector semi-rational nonautonomous rogue waves for a coupled time-dependent coefficient fourth-order nonlinear Schrodinger system in an inhomogeneous optical fiber

Optical fibers are seen in the optical sensing and optical fiber communication. Simultaneous propagation of optical pulses in an inhomogeneous optical fiber is described by a coupled time-dependent coefficient fourth-order nonlinear Schr?dinger system, which is discussed in this paper. For such a system, we work out the Lax pair, Darboux transformation, and corresponding vector semi-rational nonautonomous rogue wave solutions. When the group velocity dispersion(GVD) and fourth-order dispersion(FOD) coefficients are the constants, we exhibit the first-and second-order vector semirational rogue waves which are composed of the four-petalled rogue waves and eye-shaped breathers. Both the width of the rogue wave along the time axis and temporal separation between the adjacent peaks of the breather decrease with the GVD coefficient or FOD coefficient. With the GVD and FOD coefficients as the linear, cosine, and exponential functions, we respectively present the first-and second-order periodic vector semi-rational rogue waves, first-and second-order asymmetry vector semi-rational rogue waves, and interactions between the eye-shaped breathers and the composite rogue waves.