含有50原子%Zn的Ag-Au-Zn合金的研究

合金AgAuZn₂具有一个与郝斯勒合金同晶型结构的β″相,这个β″相存在于一个相当广阔的成分范围里。事实上,β″相就是β′有序结构的超结构。伴随着,β″结构的形成晶格发生突然的收缩。关于Ag-Au替换对于原子分布的影响,也作了系统的观察。在Ag-Au替换过程中,Au和Ag的替换或多或少是无规律性的,但Zn原子则仍保持它们的适宜位置,而不受到影响。当成分偏离于理想化学式AgAuZn₂时,有序度的减小不仅仅是由于化学成分的乖异,而且Ag-An替换也产生了一些无序的排列。高温观察的结果指出:Ag多合金的β′-β转变温度随着Au含量的增加而升高,而β相只能在高温度存在。少量的Au大大地提高了由淬炼而得到的β′相的稳定度。但是Au多的合金无论是在室温和高温都是具有β′结构的。     

利用电子束浮区区熔法制备钼单晶体

本文简单介绍自制的1.5千瓦电子束浮区区熔装置及其工作情况。应用这种装置我们制备了直径4毫米、长2—5厘米的钼单晶体,并掌握了制备定向单晶体的实验技术。制备的钼单晶体没有择优取向;显微镜观察发现晶体表面有大量的台阶(高度在2.3×10^-5—6.3×10^-4厘米),初步推断为蒸发台阶。 关键词：     

隧道二极管伏安曲线二次微商与直流偏压关系的测量

本文提供测量隧道二极管伏安曲线二次微商与直流偏压关系的谐波分析法。着重讨论测量原理,电路设计和误差对结果的各种影响。同时,指出进行这项工作对隧道二极管应用和它的物理性质研究的意义。文中介绍了典型测量结果。并对隧道二极管作低电平检波器应用的价值作了一些定量的讨论。     

Poisson Traffic Processes in RGSMP and Generalized Networks

1.Introductiontrafficprocessesinqueueingnetworksareanimportantoperatingfacetofsuchmodels,aswellasvaluableinthestudyofvaliddecompositionsofnetworks.IfwefindsometrafficprocessesinanetworkPoisson,thenitoftenrendersthemathematicalanalysistractable.Generalized…     

关于多项式多重卷积利用差分与移位算子的计值法

Here concerned and further investigated is a certain operator method for the computation of convolutions of polynomials. We provide a general formulation of the method with a refinement for certain old results, and also give some new applications to convolved sums involving several noted special polynomials. The advantage of the method using operators is illustrated with concrete examples. Finally, also presented is a brief investigation on convolution polynomials having two types of summations.     

Magnetic Heat Transfer Enhancements on Fin-Tube Heat Exchangers

通过DNS方法解耦合的三维非稳态流动和固流体能量方程组,本文研究了两平行磁质平板和圆管所组成的肋片式圆管换热器单元与震荡流体间的传热过程.对不同的磁场频率和振幅的三维动态流热场的模拟结果表明增强磁场频率和振幅能很有效地增加周期平均传热强度达到强化传热的目的.     

CONFORMATION AND CHAIN PACKING STRUCTURES OF POLY (ρ-PHENYLEN BENZOBISTHIAZOLE) BY MOLECULAR SIMULATION*

The conformation, the chain packing stabilization and the unit cell modeling of poly(p-phenylene benzobisthiazole) have been investigated by using molecular simulation techniquein the present work. A coupling behaviour of σ-bond rotations at either side of the pheny-lene ring or the heterocyclic ring was found surely to exceed a length of the repeat unit ofthe polymer chain. For a single chain model, the stable torsion angle of the repeat resultedat 14°. In the crystalline cell minimization, the dihedral angle along the polymer chaincould even be stabilized in various values. It therefore indicates that the intermolecularinteraction does play a considerable role for this polymer forming the conformation. Ac-cording to cohesive energies calculated for these unit cell models, the torsion angle in themost stable crystalline cell is 0°. When the chains packing together, there exist so manyenergy stable wells along the chain axis 0.35--0.36nm apart from neighbouring chains.Most of the unit cells have quite closed cohesive energies. These factors thus cause thedifficulty of forming an unique perfect crystalline structure of the polymer. The presentstudy suggested a number of reasonable unit cells, and the most stable crystalline structurefor this polymer that is monoclinic, non-primitive unit cell.     

银锌合金中的β相变

Owen与Edmunds曾经指出:银锌合金Ag-Zn由β相区骤冷后得到有序的体心立方结构β′相;缓冷则得到六角晶系ζ相;但在β相区进行高温观察,则只得无序的体心立方结构β相(图1)。然而对于相变机构及超结构β′相的性质他们并未说明。     

利用红外吸收积分强度进行碳氢化合物中的族分析

本文对于利用红外吸收光谱的积分强度来进行碳氢化合物的族分析作了初步尝试。从分析原子团CH₂及CH₃的结果来看,这方法是可以利用的。     

PHOTOREACTIONS ASSOCIATED WITH IN VITRO HEMOLYSIS IN ERYTHROPOIETIC PROTOPORPHYRIA*

Abstract— –Photohemolysis of erythrocytes. from patients with erythropoietic protoporphyria results from damage to the cell membrane following photoexcitation of the protoporphyrin molecule by 400 nm radiation. Photochemical reactions were assessed for their roles in initiating cell destruction in an in vitro model in which erythrocytes from patients with erythropoietic protoporphyria were irradiated. Electron transfer properties were demonstrated using 2,3,6-trichloroindophenol as an electron acceptor. Photohemolysis of these abnormal cells is due to cell membrane damage initiating colloid osmotic hemolysis. Additional data are offered demonstrating that this type of photohemolysis is oxygen-dependent, associated with peroxide formation, and preceded by increased osmotic fragility. An hypothesis explaining the interrelationship of the photochemistry of protoporphyrin with the photobiologic observation of hemolysis is offered.