Large Deviation Techniques Applied to Systems with Long-Range Interactions

We discuss a method to solve models with long-range interactions in the microcanonical and canonical ensemble. The method closely follows the one introduced by R.S. Ellis, Physica D 133:106 (1999), which uses large deviation techniques. We show how it can be adapted to obtain the solution of a large class of simple models, which can show ensemble inequivalence. The model Hamiltonian can have both discrete (Ising, Potts) and continuous (HMF, Free Electron Laser) state variables. This latter extension gives access to the comparison with dynamics and to the study of non-equilibrium effects. We treat both infinite range and slowly decreasing interactions and, in particular, we present the solution of the α-Ising model in one-dimension with 0 ⩽ α < 1.     

动能定理在活动物体和固定物体的应用

学生对在运动的参考系中应用动能解题时,总感觉没有把握,不知如何下手,因而常常解错. 如何让学生解决活动坐标系上出现的问题呢? 首先应使学生明白,物体的速度是相对参考系而言的,参考系选取不同,物体的相对速度不同,具有的动能也不同.     

红外光谱技术在翡翠鉴定中的应用

在翡翠贸易中,鉴定天然翡翠和处理翡翠是一个非常重要的问题。传统的翡翠鉴定方法,主要依赖于折射仪、宝石显微镜、滤色镜和分光镜进行检测,而所有这些方法对于鉴定处理翡翠。这种方法不仅可以鉴定未镶嵌的翡翠,而且还可以鉴定镶嵌翡翠和一些大型的翡翠饷品,如手镯、挂件和串珠等。     

Study on Application of Hypervirial Theorem in the Variational Method

We discuss a methodology problcm which is crucially important for solving the SchSdinger equation interms of the variational method. We present a complete analysis on the application of the hypervirial theorem for judgingthe quality of the trial wavefunction without invoking the precise solutions.     

Study on Application of Hypervirial Theorem in the Variational Method

We discuss a methodology problem which is crocially important for solving the Schodinger equation in terms of the variational method.We present a complete analysis on the application of the hypervirial theorem for Judging the quality of the trial wavefunction without invoking the precise solutions.     

红外光谱技术在罂粟籽检验中的应用

罂粟籽的检验鉴定是当前国内毒品检验工作一项新的课题，红外光谱技术可以有效，快速，准确地检验罂粟籽。     

Application of Spectroscopic Techniques to the Structural Analysis of Petroleum

INTRODUCTION

Petroleum, in the form of liquid oil or the solid asphalt, has been known for thousands of years (Speight, 1991) but, preceding the Industrial Revolution of the 19th century, its true potential was not realized. However, the advent of the Industrial Revolution caused man to turn from wood and coal to petroleum as the main source of liquid fuels. Furthermore, with the onset of the 20th century and the emergence of a technologically oriented society which has focused on the development of the automobile and the airplane, further uses have been found for petroleum products. Vast industries have emerged which rely upon the conversion of petroleum to a variety of by-products, and further uses for petroleumderived materials are still being addressed.     

Application of Spectroscopic Techniques to the Structural Analysis of Coal

Abstract

Coal is defined as an organic rock that is composed of macerals and minerals (Given, 1988). The macerals are believed to be derived from plant tissue that has been altered by microbial, thermal, and nonbiological processes in locales that are often referred to as “peat swamps.” One of the issues that often requires debate is the extent to which thermal processes have played in coal formation, and the extent of temperature increase during the metamorphosis of plant material to coal.     

An Isserlis’ Theorem for Mixed Gaussian Variables: Application to the Auto-Bispectral Density

This work derives a version of Isserlis’ theorem for the specific case of four mixed-Gaussian random variables. The theorem is then used to derive an expression for the auto-bispectral density for quadratically nonlinear systems driven with mixed-Gaussian iid noise. C.C. Olson is a NRC Postdoctoral Research Associate.     

波谱分析技术在宝石鉴定中的应用评述

波谱分析技术已被成功地应用于宝石学研究和宝石鉴定领域,如红外光谱技术,拉曼光谱技术和顺磁共振技术均可以有效,快速,无损和准确地鉴定宝石的类别,如天然宝石,人工合成宝石和优化处理宝石。     

Application of Autoradiography to the Investigation of New Doping Techniques of Semiconductor Materials

The development of technology of new semiconductor devices requires fundamental studies of a number of phenomena taking place in semiconductors during the doping process or accompanying the doping process.

These studies are concerned with the following problems:

1. Diffusion of gold in silicon and the effect of diffusion layers (particularly phosphorus layers) and epitaxial silicon layers on the distribution of gold in thin silicon plates.

2. Distribution of admixtures in silicon introduced with the aid of the ion implantation technique. Our studies concerned with the second of the above mentioned problems comprised an autoradiographic examination of the homogeneity of the beam of phosphorus ions implanted in silicon, and a study of some apparatus factors and of the purity of the basic material on the implantation.     

近红外技术在物理特性领域的应用

介绍了近红外光谱分析技术的原理及特点,综述了近红外分析技术在制药、纺织、石化、农业、烟草、木材等行业物理特性领域的应用,认为该技术的应用将会越来越宽广,并对该技术在物理特性领域的应用进行了展望.     

Application of Optical Techniques to Investigation and Identification of Microorganisms: a Review

Optics and Spectroscopy - Identification and investigation of microorganisms plays a central role in the diagnostics of infectious diseases; therefore, implementation of novel technologies to...     

A Counter-Example to the Theorem of Hiemer and Snurnikov

A planar polygonal billiard $\mathcal{P}$ is said to have the finite blocking property if for every pair (O, A) of points in $\mathcal{P}$ there exists a finite number of “blocking” points B ₁,...,B _n such that every billiard trajectory from O to A meets one of the B _i 's. As a counter-example to a theorem of Hiemer and Snurnikov, we construct a family of rational billiards that lack the finite blocking property.     

Theorem on the origin of phase transitions

For physical systems described by smooth, finite-range, and confining microscopic interaction potentials V with continuously varying coordinates, we announce and outline the proof of a theorem that establishes that, unless the equipotential hypersurfaces of configuration space Sum(v)=[(q(1),...,q(N)) subset R(N)/V(q(1),...,q(N))=v], v subset R, change topology at some v(c) in a given interval [v(0),v(1)] of values v of V, the Helmoltz free energy must be at least twice differentiable in the corresponding interval of inverse temperature (beta(v(0)),beta(v(1))) also in the N--> infinity limit. Thus, the occurrence of a phase transition at some beta(c)=beta(v(c)) is necessarily the consequence of the loss of diffeomorphicity among the [Sigma(v)](vv(c)), which is the consequence of the existence of critical points of V on Sigma(v=v(c)), that is, points where inverted Delta V=0.     

核技术农业应用与展望

本文综述了我国核农学的研究领域及国际上的研究现况,并介绍了我们在这一领域内取得的成果和发展前景。The research status of nuclear agronomy in our country and its development in othercountries are summaried in this paper. The results obtained in nuclear agronomy and its prospect arealso introduced.     

Revisiting Noether's Theorem on constants of motion

In this paper we revisit Noether's theorem on the constants of motion for Lagrangian mechanical systems in the ODE case, with some new perspectives on both the theoretical and the applied side. We make full use of invariance up to a divergence, or, as we call it here, Bessel-Hagen (BH) invariance. By recognizing that the Bessel-Hagen (BH) function need not be a total time derivative, we can easily deduce nonlocal constants of motion. We prove that we can always trivialize either the time change or the BH-function, so that, in particular, BH-invariance turns out not to be more general than Noether's original invariance. We also propose a version of time change that simplifies some key formulas. Applications include Lane-Emden equation, dissipative systems, homogeneous potentials and superintegrable systems. Most notably, we give two derivations of the Laplace-Runge-Lenz vector for Kepler's problem that require space and time change only, without BH invariance, one with and one without use of the Lagrange equation.     

土壤有机质研究中的核磁共振技术

土壤有机质是土壤的重要组成部分,土壤有机质的存在直接或间接地影响土壤的物理、化学和生物等许多性质. 所以对土壤有机质的研究受到了科研工作者的广泛关注. 本文在介绍了几种常用的检测土壤有机质的分析测试手段基础上,结合土壤学的研究新热点,详细介绍了核磁共振技术的应用,表明了它是目前研究土壤有机质的主要测试手段之一.     

The Application of Digital Filtering to Phase Recovery when Surface Contouring using Fringe Projection Techniques

If structured light consisting of parallel stripes, or fringes, is projected onto a surface, then the surface acts as a phase modulator, with the amount of modulation at any point depending upon the height of the surface at that point. In recent years considerable effort has been devoted to the problem of fringe demodulation, with prominence given to techniques using fringe-phase stepping and Fourier analysis. It has long been known that phase demodulation is possible using a system of filters, and the technique has been widely used in the related area of frequency demodulation in radio. In this paper the development of phase demodulation using a system of digital filters is considered. For the accurate recovery of image phase it is necessary for the filters to introduce zero phase shift, or to have a phase shift proportional to frequency. The design of the digital filters is considered and their performance is assessed using the signal from a real modulated fringe pattern and a simulated signal. It is shown that the demodulation technique works well, even with a poor signal-to-noise ratio. © 1997 Elsevier Science Ltd. All rights reserved.