高频燃烧—红外线吸收法测定硅钡铁合金中的碳和硫

研究了不同助熔剂对硅钡铁合金中碳和硫积分曲线的影响,优选了测定条件,用于硅钡铁合金中碳和硫的测定,获得较满意的结果.     

高清晰度录象机

一、前言在高清晰度电视系统中完成节目制作的输出或保存工作的录象机,从用途上区别可以分为演播室用VTR,指日可待的家庭用MUSE方式VTR,一直到视频唱盘重放装置。从记     

SMT的现状及其质量管理

表面贴装技术(SMT)发展迅速,表面安装生产过程的自动化程度不断提高,目前对于整个生产过程不仅要求其产量高,而且要求产品质量可靠。因其生产过程为链状,故其质量管理的常见方式是:在生产过程中各环节分别把关,不将次品送至下工序。具体实施就是在各工序后设置相应的检验设备(或生产设备中内含相应检验功能)。如图1     

光电子集成器件

以光通信应用为中心,研制了激光器,发光二极管,光探测器等半导体光电器件,并且已经用于很多实用化系统。要使这些发光,和探测器件工作,必须要有驱动电路和放大电路。由于半导体光电器件和电子电路之间的互连会直接影响到响应速度和噪声特性,所以这是在系统结构方面必须注意的问题之一。在力求解决这种光一电互连问题的同时,考虑并提出了一种性能更高,功能更多的新一代器件,这就是光电子集成电路。     

Calculation of High Frequency Complex Permeability of Carbonyl Iron Flakes in a Nomagnetic Matrix

The carbonyl iron flakes are fabricated by high-energy ball milling. The effective permeability is measured and calculated for the composite consisting of flakes embedded in a nonmagnetic matrix. The magnetic flakes with a shape anisotropy and random spatial distribution of normal direction are considered to calculate the complex permeability of magnetic flake materials. Its analytical model is derived from the Landau-Lifshitz-Gilbert equation and Bruggeman ＇s effective medium theory. The calculated results agree well with the experiment.     

Three-dimensional analysis on plates

I.IntroductionGenerally,asathree-dimensionaI(3-D)solid-theplateshouldbeanalysedwiththethickplatetheory.Thethickplatetheoryismultifarious:Acust0marythick[heoryoriginatesfromvariousmodificationsofthethinplatetheory,whichisbasedonKirchhoffLovehypothesis'with…     

改变云芝多糖的化学结构提高其抑瘤活性的研究

本文将长白山野生云芝子实体提取的多糖,用选择性氧化和还原及部分水解的方法,切断其β(1-6)糖苷键,明显提高了云芝多糖的抑瘤活性。此外,未脱色的云芝多糖抑瘤活性较脱色者高。     

FNR-Ⅰ核磁共振波谱仪

基于自旋回波的原理研制成功了一台专用于分析磁性材料的核磁共振波谱仪。其工作频率为25-80MHz;输出功率10W,可用它在77-300°k范围测量铁磁材料的共振谱线,增强因数和自旋-自旋弛豫时间T₂;它也可用于测量非磁性固体的宽核磁共振谱线。     

PPAR激动剂的定向设计、虚拟筛选及合成

过氧化物酶体增殖因子活化受体(PPAR)是核受体超家族的一员.基于受体结构的药物分子设计与组合化学策略相结合,构建了过氧化物酶体增殖因子活化受体(PPAR)激动剂的虚拟化合物库.将已知小分子配体(GW409544)与PPAR晶体复合物进行剥离,得到受体的活性构象,并利用此活性受体分子与虚拟库中小分子进行对接和虚拟筛选,得到理论上结合较强的化合物,并对这些化合物进行合成,共合成9个新化合物.活性筛选结果显示化合物对PPAR具有一定的亲和力,其中有三个化合物显示出对PPARα,PPARγ的双重激动作用,从而指导新活性化合物的设计和合成.     

Mǒsbauer study of the field induced uniaxial anisotropy in electro-deposited FeCo alloy films

Thin ferromagnetic films with in-plane magnetic anisotropy are promising materials for obtaining high microwave permeability.The paper reports a Mo¨ssbauer study of the field induced in-plane uniaxial anisotropy in electro-deposited FeCo alloy films.The FeCo alloy films were prepared by the electro-deposition method with and without an external magnetic field applied parallel to the film plane during deposition.Vibrating sample magnetometry and Mo¨ssbauer spectroscopy measurements at room temperature indicate that the film deposited in external field shows an in-plane uniaxial anisotropy with an easy direction coinciding with the external field direction and a hard direction perpendicular to the field direction,whereas the film deposited without external field does not show any in-plane anisotropy.Mo¨ssbauer spectra taken in three geometric arrangements show that the magnetic moments are almost constrained in the film plane for the film deposited with applied magnetic field.Also,the magnetic moments tend to align in the direction of the applied external magnetic field during deposition,indicating that the observed anisotropy should be attributed to directional ordering of atomic pairs.