中立型泛函微分方程的周期解

本文考察中立型泛函微分方程的ω-周期解的存在性,并且获得一些结果,推广了Yoshizawa的结果。     

烷基硫醚与单重态氧反应速度常数的测定

近年来,单重态氧在光氧化反应中所起的作用越来越受到重视。在新合成途径的开辟、高分子材料老化的研究、生化药物作用机理的探讨等方面,单重态氧都起着相当活跃的作用。在研究某一化合物与单重态     

Nonlinear Flow Numerical Simulation of an Ultra-Low Permeability Reservoir

A nonlinear flow mathematical model is established and the grid equation is deduced. A nonlinear flow reservoir numerical simulation program is compiled. The permeability loss coefficient is used to describe the permeability loss. A pilot calculation is made on the basis of actual field data, which reflects the reservoir development characteristics. The numerical simulation program based on nonlinear flow can anticipate the dynamic characteristics of the ultra-low permeability reservoir exploitation more exactly.     

脑电信号的标度分析及其在睡眠状态区分中的应用

脑电信号具有长程幂律相关性及多重分形的标度特性,并随生理病理状态改变.本文首次针对睡眠脑电信号应用单重分形去趋势波动分析(detrended fluctuation analysis,简记为DFA)方法与多重分形奇异谱对睡眠脑电信号的标度特征进行系统的对比研究.发现DFA标度指数α对于不同导联和样本组间的差异较为敏感,随睡眠状态的变化不规律;而多重分形奇异强度区间Δα随睡眠状态的变化更为规律,睡眠Ⅰ期至Ⅳ期不断增大,并且导联间差异和样本组间差异均较小.多重分形Δα参数更适合作为判定睡眠状态的定量参数.     

Primary result of ^236U measurement with accelerator mass spectrometry at CIAE

The rare isotope ^236U has a half-life of 2.342（3）×107 years, and is produced principally by thermal neutron capture on ^235U. The isotopic atom ratio of ^236U/^238U depends on the integral thermal neutron flux received by the material of interest. ^236U is potentially useful as a ＂fingerprint＂ for indicating the presence of neutron-irradiated uranium usually originating from nuclear activity. By extracting negative molecular ion UO^- from the uranium oxide target, simulating the ^236U^16O^- beam transport with ^238U^16O^- and ^208Pb2^16O^- pilot molecular ion beam, transporting the ^236U-containing ion beam with a high resolution injection magnet analyzer and electrostatic analyzer system, and finally identifying and detecting ^236U with a time-of-flight detector （TOF）, a method for AMS （Accelerator Mass Spectrometry） measurement of ^236U was established on the HI-13 Accelerator AMS system at China Institute of Atomic Energy.     

Primary result of ~(236)U measurement with accelerator mass spectrometry at CIAE

The rare isotope 236U has a half-life of 2.342(3)×107 years,and is produced principally by thermal neutron capture on 235U.The isotopic atom ratio of 236U/238U depends on the integral thermal neutron flux received by the material of interest.236U is potentially useful as a fingerprint for indicating the presence of neutron-irradiated uranium usually originating from nuclear activity.By extracting negative molecular ion UO- from the uranium oxide target,simulating the 236U16O- beam transport with 238U16O- an...     

HIV-1整合酶的RNA适配子的筛选及活性研究

通过SELEX技术已经筛选到了多种HIV-1病毒相关蛋白,如：逆转录酶、Rev和Tat蛋白、核壳蛋白等的核酸适配子,然而以HIV-1整合酶为靶点的DNA或RNA适配子却鲜有报道．在结合缓冲液中以10mmol．L-1的Mg2＋作为辅助因子,加入100mmol．L-1KCl筛选到了三个具有相似结构和托的适配子IN1,IN2和IN3．亲和力最高的适配子IN1的Kd为145nmol．L-1,保守区富含乌嘌呤碱基（G）,缺失任何一个茎环结构会使亲和力减弱．缺失右端固定序列的IN1-L的Kd为283nmol．L-1,虽然不能形成四链结构但可以被G-四链T40214竞争结合,可能与T40214具有相同的结合位点．     

信号延时叠加提高激光雷达探测信噪比

以激光雷达回波信号的频谱特征为基础,提出了用信号延时叠加来提高激光雷达探测信噪比的方法.通过实验测量获取了大量激光雷达回波信号,并以此为基础,讨论了信号延时叠加提高激光雷达探测信噪比的可行性.结果表明:在系统带宽50 MHz、回波脉宽30 ns的条件下,通过信号延时叠加可提高激光雷达的探测信噪比在40%以上,且存在最佳的延时时间.     

对偶超导模型n=90—110的近似解析解

研究了对偶超导模型的大n涡旋。 基于变分原理得出了Abelian Higgs模型在n=90—110的近似涡旋解析解, 并计算了涡旋张力对n的依赖性。 发现, 每根涡旋的张力大致随n线性增长。 期望该解对理解Abelian Higgs模型中的大量子数涡旋的墙行为具有一定价值。 The large n vortices in the dual superconductor model was investigated. An approximate analytical solution was obtained for n fold quantized vortices with n=90—110 by variationally solving the AbelianHiggs model, and the vortex tension was calculated as a function of n. It was found that the vortex tension rises linearly as n grows. It is hoped that our solution shines light on the understanding of the wall behavior of the large n vortices in Abelian Higgs model.     

具强迫力的奇数阶中立型微分方程的振动性

Abstract. In this paper, the forced odd order neutral differential equations of the form are con-sidered