由5-唑烷酮合成α-天冬氨酰肽类的简便方法(英文)

用一锅法制得了２－三溴甲基－３－甲酰基－５－氧－４－口恶唑烷乙酸，它与氨基酸酯反应形成题称化合物Ｎ－甲酰基－α－天冬氨酰肽类。     

COHOMOLOGY VANISHING IN HILBERT SPACES

§1. Introduction Oka [40] proved that any additive Cousin problem is solvable in a domain of holomorphyin Cn. Oka [41]-Cartan [2, 3]-Serre [46] generalized this as the theorem B for analyticcoherent sheaves over Stein spaces. J. P. Serre [47] proved…     

On semisymmetric cubic graphs of order 6p~2

A graph r is said to be G-semisymmetric if it is regular and there exists a subgroup G of A := Aut(Г) acting transitively on its edge set but not on its vertex set. In the case of G. = A, we call r a semisymmetric graph. The aim of this paper is to investigate (G-)semisymmetric graphs of prime degree. We give a group-theoretical construction of such graphs, and give a classification of semisymmetric cubic graphs of order 6p2 for an odd prime p.     

Acousto-electric effect in bone

In the present work,acoustoelectric effect in bone has been investi-gated.Rectangular bone samples prepared from the middiaphysis of the wallof animal bone are exposed by ultrasonic field having frequency of 2.5 MHz.The bone matrix changes under ultrasound exposure which results into the gen-eration of potential in bone.The present study may be helpful in the develop-ment of acousto-electric devices.     

EXISTENCE OF POSITIVE PERIODIC SOLUTION TO A CLASS OF NEUTRAL DELAY COMPETITION MODEL

By means of the theory of coincidence degree, sufficient condition for the existence of positive periodic solution to certain neutral delay competition model is obtained.     

Synthesis of a Novel Chiral Trihydroxamic Acid Containing L-Pro-L-Ala-L-Ala-β-(HO)Ala-OMe Unit

Iron is indispensable for almost all life forms1. Under iron-deficient environments, microorganisms secrete siderophores to chelate ferric ions and then, transport ferric ions into cells by specific receptor recognitions2,3. Siderophores have many clinica…     

一种改进的谐振参数扰动法及其在DC/DC变换器混沌控制中的应用

种改进的谐振参数扰动法来控制混沌，该混沌控制方法引入了基于非线性映射的调制，其控制目标可以是任意周期的轨道，而不是原混沌吸引子中的嵌入轨道。作为一个应用实例，文中描述了该方法在电流模式控制dc/dc变换器中的应用结果。     

互补金属氧化物半导体焦平面阵列输入电路的1/f最佳化

在光电探测系统中,互阻放大器的噪声特性对光伏探测器的增量电导率很敏感。本文指出,由于放大器产生的1/f噪声转角频率是加在探测器上的偏压的函数。在冷焦平面阵列内二极管的1/f噪声转角频率也是反偏压的函数,但是有最佳偏压,即不是OV。当必须使用具有大1/f噪声转角频率的互补金属氧化物半导体放大器时,此条件就变得很重要了。     

5.5到21.7MeV/A28Si+197Au系统的裂变测量(Ⅰ)线动量转移和偏离反应平面分布

用5.5到21.7MeV/A²⁸Si+¹⁹⁷Au,测量关联裂片的速度及角分布.实验表明:入射能超过10MeV/A时,出现非完全熔合裂变(ICF);E_cm>200MeV时,伴随ICF又出现跟随裂变(SF).从线性动量转移(LMT)分布中,提取了SF产额对总裂变产额的比值.从关联裂片偏离反应平面的分布中,给出了分布宽度与单核子激发能的线性关系式.     

一种实用的2.17K液氦容器

本文介绍一种用于获得λ点以下温度加压过冷态超流氦的低温减压系统。对该系统中的关键部件流量压缩器作了较详细的描述。最后,结合一个实用的2.17K液氦容器,给出了可供选择的流量阻抗值及其试验结果。