二代树状碳硅烷液晶研究Ⅰ.端基含36个丁氧基偶氮苯介晶基元

用发散法合成周边含36个丁氧基偶氮苯介晶基元(M5)端基新的二代树状碳硅烷液晶(D2),并用元素分析,氢谱,激光质谱,红外,紫外,偏光显微镜,DSC和WAXD法表征.D2为向列相,与M5相同,二代树状物相态由介晶基元相态决定.D2液晶态相行为是K85N107I103N69K,其熔点比M5降低27～41℃,清亮点比M5降低17～18℃,液晶态温区比M5加宽10～23℃.二代碳硅烷(D2)与一代碳硅烷(D1)相比熔点增加2～3℃,清亮点降低26～29℃,液晶态温区减少29～31℃.在二代树状物中观察到S=+3/2的高强向错.     

双光学平板莫尔条纹实验

传统的莫尔(Moire′)条纹一般是在一组透射光栅上实现的。本文提出了一种实现莫尔条纹的新方法——双光学平板法。利用两块相同厚度的光学平板产生的多光束干涉效应来产生莫尔条纹。原理光线斜入射至一光学平板时,其反射光会在远处屏幕上产生一组清晰的干涉条纹。再使第一平板上的反射光以同样入射角入射到第二平板上。最终的反射光为两组干涉条纹的重叠,即产生了莫尔条纹。实际光路见图,激光束由透镜L略加扩束后到达固定平     

Pseudo-Spin-Valve Trilayer Using Amorphous CoNbZr Layer： Giant Magnetoresistance, Domain Structures and Potentials for Spin-Electronic Devices

We propose a pseudo-spin-valve (PSV) trilayer using amorphous CoNbZr Mloy for soft magnetic layers. The giant magnetoresistance (GMR), domain structures and their variation upon thermal annealing are investigated. The GMR effect is not only stable up to 300℃ but also enhanced due to the improvement of the interfaces between Cu and magnetic layers. With high annealing temperature, the magnetoresistance (MR) ratio decreases rapidly as a result of serious layer interdiffusion. Dense stripe domains, which disappear after annealing at 300℃ for 1h, are observed in the sandwiched films. It is found that after patterning to elliptic stripe with aspect ratio of 6:1, the trilayers have a single domain and their MR ratio increases. The dynamic MR behaviour under an ac magnetic field indicates that the patterned stripes have good linear MR responses. Therefore, it is believed that the CoNbZr/Cu/Co PSV trilayers have strong potentials for spin-electronic devices including magnetic random access memory.     

D→Klv～l衰变过程的研究

用光锥QCD求和规则研究D→Klv～_l衰变过程，首先计算D→K跃迁形状因子，通过构造新的关联函数，消除了twist-3波函数的不确定性给计算结果所带来的影响，从而使计算结果更加精确. 计算得到的分支比与最近的实验数据相一致. 关键词： QCD光锥求和规则 D介子半轻衰变 分支比 形状因子     

小朋友学习珠心算

第三节 珠算基础知识 一、算盘构造图 珠算式心算使用的算盘可以分为两种:第一种是普通珠算盘;第二种是珠心算算盘。它们的构造请看后面的图式。 (一)普通珠算盘构造图     

小朋友学习珠心算

二、加减混合五行加余 （一）原理 加减混合十五行，珠心算技术鉴定与竞赛题，减题占五行。加余中，进66…6，退55…5，总体进11…1。加减混合二十行，珠心算竞赛题，减题占七行。加余中，进88…8，退77…7，总体进11…1。     

Dynamic Mechanism of Sustainable Molecular Orientation Generated From Cyclic Rotational States

Recently, two papers presented by Ortigoso et al. [Phys. Rev. Lett. 93 （2004） 073001 and Phys. Rev. A 72 （2005） 053401] develop a novel strategy in which the best sustainable molecular alignment/orientation has been achieved. We intend to analyse the dynamic mechanisms, including those Ortigoso et al. have not clarified.     

弹性体型聚氨酯和聚碳酸酯共混物的形态结构

用ＤＳＣ、ＷＡＸＤ和ＳＡＸＳ研究了溶液共混的弹性体型聚氨酯（ＰＵ）／聚碳酸酯（ＰＣ）共混物的结构。结果表明，ＰＵ／ＰＣ为部分相容体系；共混过程中，溶剂ＤＭＦ的诱导作用使ＰＣ形成结晶，其长周期与ＰＵ硬段形成微相的长周期相近     

Synthesis and Insulin—sensitizing Activity of a Series of 2—Benzyl—1,3—dicarbonyl Derivatives

A series of 2-benzyl-1,3-dicabonyl derivatives was synthesized.Their insulin-sensitizing activity was evaluated in 3T3-L1 preadipocyte cells.Compounds3,26 and 27 were found to possess strong insulin-sensitizing activity in vitro and were selected for further hypoglycemic evaluation in vivo.     

化工工人体内微量元素积累与健康的关系

论述了化工作业工人长期接触有害元素会引起体内有害元素积蓄，微量元素平衡失调，产生潜在的职业危害，建议定期对临床尚未发现中毒现象的作业工人进行体内微量元素情况监控，以预防职业中毒。并提出采用适当补充某些必需元素的方法，可预防这种危害。