Application of ^41Ca Tracer and Its AMS Measurement in CIAE

The man-made calcium isotope ^41Ca is an ideal tracer for the study of calcium metabolism. We represent the first application of accelerator mass spectrometry (AMS) measurement of ^41Ca tracer in China. The technique is being applied to the research field of cell messenger at the China Institute of Atomic Energy (CLAE). The sample preparation methods and the AMS measurements are discussed and some interesting results are presented.     

Conformal invariance, Noether symmetry, Lie symmetry and conserved quantities of Hamilton systems

In this paper, the relation of the conformal invariance, the Noether symmetry, and the Lie symmetry for the Hamilton system is discussed in detail. The definition of the conformal invariance for Hamilton systems is given. The relation between the conformal invariance and the Noether symmetry is discussed, the conformal factors of the determining expressions are found by using the Noether symmetry, and the Noether conserved quantity resulted from the conformal invariance is obtained. The relation between the conformal invariance and the Lie symmetry is discussed, the conformal factors are found by using the Lie symmetry, and the Hojman conserved quantity resulted from the conformal invariance of the system is obtained. Two examples are given to illustrate the application of the results.     

Conformal invariance and conserved quantities of general holonomic systems in phase space

This paper studies the conformal invariance and conserved quantities of general holonomic systems in phase space. The definition and the determining equation of conformal invariance for general holonomic systems in phase space are provided. The conformal factor expression is deduced from conformal invariance and Lie symmetry. The relationship between the conformal invariance and the Lie symmetry is discussed, and the necessary and sufficient condition that the conformal invariance would be the Lie symmetry of the system under the infinitesimal single-parameter transformation group is deduced. The conserved quantities of the system are given. An example is given to illustrate the application of the result.     

THE COMPUTATION OF PARTIAL COHERENCE FUNCTION APPLIED FOR SOUND SOURCE IDENTIFICATION

In this paper,a new method is applied to get the computation formula of partial coherence function.The main attention is paid to the computation formula of the partial coherence function with three andfour signals.The advantages of the method discussed in the paper are clear in physical meaning and easyto compute at the end of the paper,the application of the method to the identification of an aircompressor noise source is presented and the results are satisfactory.     

Time-Resolved Terahertz Spectroscopy with Free-Space Electro-Optic Sampling

We present a time-resolved ultrafast measurement in terahertz (THz) frequency region by means of the free-space electro-optic sampling. The fast delay scan technique is used to suppress the noise with low frequency and to improve the signal-to-noise ratio of the system. The transmission spectra of different materials are obtained.The optical properties of these materials in a THz region are shown. The broadening of spectrum and chirping phenomena are illustrated. We find that polystyrene is an excellent material for the THz application.     

Electrostatic Nonlinear Structures in Dissipative Electron--Positron--Ion Quantum Plasmas

Low frequency （in comparison to ion plasma frequency） ion-acoustic shocks and solitons in superdense electronpositron-ion quantum plasmas are studied. The quantum hydrodynamic model is used incorporating quantum Bohm forces and Fermi-Dirac statistical corrections to derive the deformed Korteweg de Vries-Burgers （dKdVB） equation in weakly nonlinear limit. The travelling wave solution of dKdVB equation is presented and results are discussed in different limits. It is found that shock height increases with increase of quantum pressure, positron concentration and dissipation. Further, it is seen that the width of soliton decreases with increase of quantum pressure     

Approximate any 1-state solutions of the Dirac equation for modified deformed Hylleraas potential by using the Nikiforov-Uvarov method

<正>We investigate the spin and pseudospin symmetries of the Dirac equation under modified deformed Hylleraas potential via a Pekeris approximation and the Nikiforov-Uvarov technique.A tensor interaction of Coulomb form is considered and its degeneracy-removing role is discussed in detail.The solutions are reported for an arbitrary quantum number in a compact form and useful numerical data are included.     

Femtosecond laser induced index and relief gratings in polymer films

A true single-step process suitable for fabrication of micro-periodic structure in polymer films by two- photon initiated photopolymerization and laser ablation is presented.By the right choice of the irradiation energy,the irradiated zone is modified or ablated in the 1.44-μm-thick film.The mechanism of grating generation and the potential application of the gratings in integrated optics are discussed.     

A meshless method based on moving Kriging interpolation for a two-dimensional time-fractional diffusion equation

Fractional diffusion equations have been the focus of modeling problems in hydrology, biology, viscoelasticity, physics, engineering, and other areas of applications. In this paper, a meshfree method based on the moving Kriging inter- polation is developed for a two-dimensional time-fractional diffusion equation. The shape function and its derivatives are obtained by the moving Kriging interpolation technique. For possessing the Kronecker delta property, this technique is very efficient in imposing the essential boundary conditions. The governing time-fractional diffusion equations are transformed into a standard weak formulation by the Galerkin method. It is then discretized into a meshfree system of time-dependent equations, which are solved by the standard central difference method. Numerical examples illustrating the applicability and effectiveness of the proposed method are presented and discussed in detail.     

气体喷嘴反冲传输技术及在核科学中的应用

气体喷嘴反冲传输技术是继“跑兔”装置之后发展和完善起来的适合于短寿命核素研究的一种快速而有效的在线脱束方法。 它能够将短寿命核反应产物传输至远离高辐射区的低本底场所进行收集和测量。 该技术已在加速器和反应堆上得到了广泛的应用, 是一种研究核反应、 核谱学和合成与鉴别新元素、 新核素的一种不可缺少的基本实验技术和工具。 描述了气嘴系统的结构、 基本原理、 设计要求以及它的主要特性, 特别是对系统的气体动力学机制以及各种参数对系统特性的影响等进行了讨论。 最后, 综述了它在核物理、 核化学以及质谱学等领域的应用情况, 并且给出了几个应用的典型例子。 The gas jet recoil transport technique is developed and improved as a new rapid and effective on line and off beam method following “rabbit” apparatus in the study of short lives nuclei. It can transport the short half life nuclear reaction products far from high radioactive area for collection and measurement at low background area. This technique has been widely used in the researches with accelerator and reactor. It is indispensable basic experimental technology and tool applied to nuclear reaction, spectroscopy, as well as synthesis and identification of new elements and nuclei. The basic principle, structure, design requirement and main characteristics of gas jet system are described in this paper, especially the mechanism of gas dynamics and the effect of several parameters on the system properties are discussed. Finally, the applications of this technique in several fields such as nuclear physics, nuclear chemistry and mass spectroscopy etc. are comprehensively represented. Several typical applications are also illustrated.     

CPL技术在空间飞行器上的应用

本文对ＣＰＬ技术进行了简要概述,介绍了其工作原理与工作特性,并讨论了ＣＰＬ技术在空间飞行器上的可能应用方式。其中,对ＣＰＬ技术应用于空间设备的散热进行了全面阐述,并给予理论分析;此外,对ＣＰＬ技术应用于空间设备的主动热控制,也作了简要介绍;对ＣＰＬ技术未来有发展前景的应用方式进行了展望。     

航空成像系统检调焦技术分析与展望

介绍了航空成像系统的特殊工作环境及应用需求对检调焦技术的要求,讨论了当前3种主要检调焦方法：程序标定法,光学自准直法及图像对比度法,总结并比较了3种方法的检调焦精度、检调焦时间等性能指标。最后着重讨论了基于光场成像理论与光学系统离焦深度之间的关系,对基于光场成像原理的快速检调焦技术进行了深入的分析、讨论,并对该技术在航空成像系统的应用前景进行了展望分析。     

高压电晕特性的研究

介绍应用图像增强技术解决高压电晕观测中存在问题的实验原理和依据,分析高压电晕图像的特性,讨论利用图像增强技术研制的高压电晕观测仪器的特点,举例说明该系统在输电导线电晕放电特性研究中的应用,最后指出图像增强技术在高压电晕观测中的应用前景。     

Theory of two-frequency excitation in<Superscript>14</Superscript>N NQR

A simple and effective technique for calculating the transient signals in three-level spin systems irradiated at one and two frequencies is described. All possible signals are presented and discussed. The application of the two-frequency excitation technique for the investigation of the inhomogeneity of the crystalline lattice is suggested.     

光镊技术在生命科学研究中的应用

介绍了光镊技术的工作原理和系统结构,论述了光镊技术工作特点,并结合具体的研究工作,阐述了光镊技术在单细胞、单分子等生命科学研究领域中的应用,最后给出了近年来光镊技术取得的进展和新的应用.     

多自由度测试技术的发展

介绍目前较常用的多种多自由度测试技术，给出每种测试技术的测试原理和应用场合，比较各种技术的优缺点和适用范围，讨论该技术发展的方向。     

数据库技术在离线物理分析中的应用

讨论了如何利用数据库技术解决高能物理分析中遇到的一些问题,利用一种ＳＱＬ语方数据库与高能物理分析软件包ＰＡＷ（ｐｈｙｓｉｃｓ ａｎａｌｙｓｉｓ ｗｏｒｋｓｔａｔｉｏｎ）的接口技术,可以大大提高ＰＡＷ的数据操作功能和方便实用性,展现了数据库技术在离线数据物理分析中的一个新的应用领域和前景。     

灵巧结构与蒙皮中的特种光纤

介绍适用灵巧结构与蒙皮的几种特殊光纤的结构，特性，埋置技术及使用情况，讨论今后可能的发展趋势。     

New Possibilities of OD ESR: Vacuum Ultraviolet Generation of Radical Ion Pairs

A new version of the optically detected electron spin resonance (OD ESR) technique using vacuum ultraviolet radiation to generate radical ion pairs is discussed. The technique can be used to study the spin-correlated processes of charge recombination in thin films that can be useful in spintronics. Distinctive features of photoionization and high-energy (including X-ray) ionization are discussed. The first results obtained by the technique in the study of charge recombination in polymeric and liquid crystal films are presented. The results of the concurrent observation of the OD ESR and electron cyclotron resonance (ECR) in the low-pressure gas over the sample are outlined. A possible application of ECR in the context of the OD ESR spectroscopy is suggested.     

DSP技术在核磁共振数据系统中的应用

讨论了数字信号处理技术在核磁共振数据采集与处理系统中的应用,介绍比较了三种系统的原理、特点及优缺点.