The Squeezing Effect in a Mesoscopic RLC Circuit

Using the path integral method we derive quantum wave function and quantum fluctuations of charge andcurrent in the mesoscopic RLC circuit. We find that the quantum fluctuation of charge decreases with time, oppositely,the quantum fluctuation of current increases with time monotonously. Therefore there is a squeezing effect in the circuit.If some more charge devices are used in the mesoscopic-damped circuit, the quantum noise can be reduced. We also findthat uncertainty relation of charge and current periodically varies with the period π/2 in the under-damped case.     

同时估计回归函数零点及噪声参数

对未知的回归函数以 ARMA 型的误差得到量测时,本文以随机逼近型算法搜索回归函数的零点,同时以参数辨识算法估计噪声模型中的未知系数阵.本文证明了两种算法以概率1的收敛性.     

Spectral Representation Theory for Dielectric Behavior of Nonspherical Cell Suspensions

Recent experiments revealed that the dielectric dispersion spectrum of fission yeast cells in a suspension was mainly composed of two sub-dispersions. The low-frequency sub-dispersion depended on the cell length, while the high-frequency one was independent of it. The cell shape effect was simulated by an ellipsoidal cell model but the comparison between theory and experiment was far from being satisfactory. Prompted by the discrepancy, we proposed the use of spectral representation to analyze more realistic cell models. We adopted a shell-spheroidal model to analyze the effects of the cell membrane. It is found that the dielectric property of the cell membrane has only a minor effect on the dispersion magnitude ratio and the characteristic frequency ratio. We further included the effect of rotation of dipole induced by an external electric field, and solved the dipole-rotation spheroidal model in the spectral representation.Good agreement between theory and experiment has been obtained.     

BEPCⅡ高频发射机和环流器的调整和测试

北京正负电子对撞机升级改造工程(BEPCⅡ)将采用的频率500MHz、输出功率250kW的高频发射机和环流器已安装、调整、测试和验收完毕,这是国内建立的第一套500MHz/250kW发射机系统.本文将详细介绍机器的调测试的原理和各项测量内容及结果, 并比较设计指标和要求,来阐述此发射机的实际技术指标和测试性能.     

硫化锌掺钴对电子结构和光学性质的影响

根据密度泛函理论对钴掺硫化锌周围的品格进行了结构优化,计算得到了钴杂质周围的晶体结构、电子态密度分布和吸收光谱.计算结果表明,由于Co原子掺入ZnS晶格常数减小,导致晶格畸变;带隙变窄;吸收峰展宽至更长波长区域.     

526例儿童指血微量元素检测结果分析

为了解吐哈油区婴幼儿体内钙、铁、锌、铜、镁的含量,使用多通道原子吸收光谱仪对门诊体查的526例0~7岁幼儿指血检测了钙、铁、锌、铜、镁。结果表明,各个年龄组中缺铁均居第一位,缺钙居第二位,缺锌居第三位,年龄越小,这3种元素含量越低。提示婴幼儿生长发育快,易缺钙,铁,锌元素,年龄越小,越易缺乏。     

溶胶凝胶法制氧化铝负载铜基超细粒子催化剂的研究

采用溶胶凝胶法制氧化铝负载铜基超细粒子催化剂的制备了氧化铝负载的铜基超细粒子催化剂，用ＴＧ－ＤＴＡ，ＸＲＤ，ＢＥＴ以及ＴＥＭ等技术手段，对催化剂的物相结构，表面孔结构，粒子形貌以及催化性能等进行了研究。结果表明，利用溶胶凝胶法，可以直接帛备出高比表面积，低堆积密度的纤维状纳米级负载型Ｃｕ／Ａｌ２Ｏ３超细粒子；活性组分以远低于纳米级的微晶粒子簇状态，均匀地分散在纳米级氧化铝载体表面上，而且在低于５０     

ISOLATION,CHARACTERIZATION AND EXPRESSION OF THE COMPLEMENTARY DNA FOR HUMAN TUMOR NECROSIS FACTOR (TNF-α)

A cDNA for human TNF-α (615bp) was isolated by means of polymerase chain reaction (PCR) using first strand cDNA from PMA-induced HL-60 cells as template. The result from sequencing the 615 bp cDNA fragment indicated that it corresponded to the entire sequence of mature human TNF coding region. Direct expression of mature human TNF was achieved using a plasmid pHT-1 constructed by ligation of the cDNA and a synthetic DNA. The IPTG-induced bacterial product (hTNF) showed cytotoxicity to mouse L-929 cells. The TNF activity was further identified by neutralization of a specific monoclonal antibody against human TNF-α. Approximately 80,000 units of activity were detected per ml of culture at A600=2.     

透射电镜像转角的测定及应用

论述了完全标定透射电镜像转角所需拍摄的二次曝光电子显微像的数量,推导了由已测的像转角间接计算其它像转角的一般公式,以Philips Cm200电镜为实例,说明了测定像转角的基本步骤,并以实例说明怎样利用像转角,把衍射花样的晶体学信息传递给电子显微像。     

一类相变的Landau-deGennes模型——高斯近似

本文对一类相变的Landau-deGennes模型(以下简称L-deG模型)进行了高斯近似和平均场近似计算,获得一些“临界指数”的数值。例如,在高斯近似下,α=0.5≠α＇,γ=1≠γ＇,ν=0.5≠ν＇等等。我们计算了比热,并与液晶MBBA的实验进行了比较,讨论了向列相-各向同性液相相变与三重临界点的关系。文中特别着重讨论了一类与二类相变临界行为的异同。我们认为,二类相变的标度律结果不能简单地挪用到一类相变的情况。