一种EPR谱图模拟软件的研制

采用Microsoft Visual BASIC 4.0 for Windows 95编写了一个EPR谱图模拟软件.此软件采用鼠标控制命令按键进行程序过程.得到的图象分辨率和色彩优于用其他早期开发的BASIC语言编写的程序,打印的黑白图象质量也很好.运算时间小于20秒.这种软件可用于多种EPR模拟应用,包括自由基EPR谱图的模拟、过渡金属离子E PR谱图的模拟和二维EPR成像的模拟.EPR成像可以彩色强度图、等高线图或三维俯视图来表示.所有的模拟图象均可用激光打印机打印成黑白图片.自由基模拟程序的数据组有2560点.EPR成像的像素一般为128×128点.     

新型X波段多功能EPR谱仪的设计与性能

本文设计和研制了一款新型X波段多功能电子顺磁共振（electron paramagnetic resonance,EPR）谱仪,并为其开发一款新的控制和读出系统（control and readout system,CRS）来操控微波脉冲的产生和信号的采集,提高了系统的集成度和可扩展性. 该谱仪可实现常规的连续波EPR（continuous-wave EPR,cw-EPR）、脉冲EPR（pulsed EPR）和瞬态EPR（transient EPR,trEPR）实验,并装配了6~300 K的无液氦变温装置,以及兼具平行模式与垂直模式的新型双模连续波谐振腔和用于脉冲EPR及trEPR的介质腔. 针对新型EPR谱仪和新谐振腔,本文利用双模连续波、脉冲和瞬态三个不同方式的EPR实验,对其功能进行了验证.     

一种新的DEPT 谱编辑方法

提出一种新的基于多元线性回归计算的无畸变极化转移增益法(DEPT)谱编辑方法．该方法使用多元线性回归对谱图中的杂信号进行拟合,获得最佳拟合系数,然后将拟合系数代入拟合公式,通过该公式对DEPT 子谱进行计算,去除杂信号,最终分别得到纯净的CH₃、CH₂、CH 子谱图．实验结果证明,使用新方法对DEPT 谱进行编辑能够很好地减少杂信号的干扰,得到只含有CH_n 信号的子谱．新方法为碳谱的解析尤其是复杂和密集的谱线的解析提供了方便．     

液体核磁共振 HSQC 实验的量子化学计算与模拟

核磁共振（NMR）异核单量子相干（HSQC）实验因具有较高的灵敏度和分辨率而被广泛用于液体大分子化合物的结构鉴定和研究．然而由于HSQC脉冲的复杂性,需要严格控制实验参数和实验条件才能得到高质量的谱图．本文基于量子力学原理对HSQC实验进行数学建模,通过理论推导、数值计算求解自旋1/2的IS双核体系在每个脉冲节点作用后的密度矩阵,然后结合二维NMR信号采样方法,使用计算机程序完成了该体系HSQC谱图的模拟,同时,还实现了乙醇分子的HSQC谱图模拟． HSQC实验的成功模拟基于对复杂演化过程的精确计算,可用于预测谱图以及实验参数改变对NMR谱图的影响,指导高质量HSQC实验谱图的采集．     

基于非均匀B样条曲线的红外数据的精确拟合及校正

红外谱图数据的精确拟合是建立标准谱图的重要组成部分,是光谱仪器正确进行定性和定量分析的基础。文章采用非均匀B样条对红外谱图数据进行曲线拟合,通过采用基于最大范数距离的B样条拟合算法,不仅解决了大容量红外谱图的精确拟合问题,同时对谱图峰值精确定位也提供了方便。文章介绍了非均匀B样条曲线,以及二阶(三阶)非均匀B样条曲线拟合的实现,重点描述了红外谱图数据拟合精度的控制方法。     

基于LabVIEW和Arduino的远程监控系统设计与实现

针对现场采集数据实时远程监控的要求,根据LabVIEW强大的功能模块和Arduino灵活易用的开发特点,提出以Arduino为控制器,采用Arduino软件与LabVIEW软件交互编程的设计思想。为解决LabVIEW在本地服务器Web发布的局限性,同时简化系统的硬件设计,增加使用的灵活性,使用云计算作为服务器,设计实现了一种基于LabVIEW和Arduino的无线串口采控和实时同步Web发布的系统。测试结果表明,该系统界面友好,运行可靠,可扩展性很强,可以在整个互联网上通过网页建立Web请求。     

在体剂量检测专用EPR数据采集与控制系统

研制了X波段在体剂量检测专用EPR谱仪的数据采集与控制系统,利用阿尔泰USB2812数据采集卡作为控制卡,在LabVIEW图形化编程开发环境中进行程序开发,实现了扫场电源的控制、微波模的显示、微波功率的控制和EPR信号的采集等功能. 数据处理程序可实现存储数据的查询、谱线基线校正和积分等基本功能,为下一步开展牙齿剂量试验研究提供了平台.     

研究固体微结构的X射线粉末衍射全谱图拟合方法

Ｘ射线粉末衍射全谱图拟合的Ｒｉｅｔｖｅｌｄ方法是一种有效的晶体结构和微结构的分析方法。本文介绍了Ｘ射线粉末衍射全谱图拟合的Ｒｉｅｔｖｅｌｄ方法的基本原理,综述了该方法中的线形分析、校正及其在晶体结构分析、微结构分析、相定量分析和衍射图谱指标化等方面应用的最新进展。文章最后介绍了在实验方案选取方面的新概念     

喇叭型开口光子晶体波导的传输谱研究

设计一种喇叭型开口二维光子晶体波导,利用时域有限差分法计算波导传输谱图。模拟结果表明：通过改变开口处光子晶体椭圆点缺陷的结构,传输谱图中将出现相应变化的缺陷模,可用于实现频率可调的窄带光子晶体滤波器。     

研究固体微结构的X射线粉末衍射全谱图拟合方法

Ｘ射线粉末衍射全谱图拟合的Ｒｉｅｔｖｅｌｄ方法是一种有效的晶体结构和微结构的分析方法。本文介绍了Ｘ射线粉末衍射全谱图拟合的Ｒｉｅｔｖｅｌｄ方法的基本原理，综述了该方法中的线形分析、校正及其在晶体结构分析、微结构分析、相定量分析和衍射图谱指标化等方面应用的最新进展。文章最后介绍了在实验方案选取方面的新概念     

EasySpin, a comprehensive software package for spectral simulation and analysis in EPR

EasySpin, a computational package for spectral simulation and analysis in EPR, is described. It is based on Matlab, a commercial technical computation software. EasySpin provides extensive EPR-related functionality, ranging from elementary spin physics to data analysis. In addition, it provides routines for the simulation of liquid- and solid-state EPR and ENDOR spectra. These simulation functions are built on a series of novel algorithms that enhance scope, speed and accuracy of spectral simulations. Spin systems with an arbitrary number of electron and nuclear spins are supported. The structure of the toolbox as well as the theoretical background underlying its simulation functionality are presented, and some illustrative examples are given.     

Application of the SCVT Orientation Grid to the Simulation of CW EPR Powder Spectra

The orientation grid obtained using the spherical centroidal Voronoi tessellation (SCVT) method is assessed for the simulation of continuous-wave electron paramagnetic resonance (CW EPR) powder spectra. The SCVT spherical code presents less distorted Voronoi cells associated to the points of the grid compared to the regular Igloo, SOPHE and EasySpin grids and similar distortions of the cells to the irregular Repulsion grid. The degree of distribution of the SCVT cells’ areas is smaller than for SOPHE, but higher than for the Igloo and Repulsion grids. All compared spherical codes have nearly the same electrostatic potential energy. Simulated CW EPR powder spectra for rhombic systems of spin S = 1/2 are similar when using the energy minimization SCVT and Repulsion spherical codes and show less intense ripples than the spectra calculated with the SOPHE and Igloo grids, but more intense than those obtained using the EasySpin grid. The classical projection method and a new modified form involving the spectral intensities at the orientations of the grid have been tested for the attenuation of the simulation noise, for grids of relatively reduced size.     

OASIS4.0—a new version of the program OASIS for phasing protein diffraction data

<正>The program OASIS4.0 has been released.Apart from the improved single-wavelength anomalous diffraction (SAD) phasing algorithm described in a separate paper,an important new feature in this version is the automation of the iterative phasing and model-building process in solving protein structures.A new graphical user's interface(GUI) is provided for controlling and real-time monitoring the dual-space iterative process.The GUI is discussed in detail in the present paper.     

An interactive graphical user interface (GUI) for the CATGIXRF program – for microstructural evaluation of thin film and impurity doped surfaces

This paper is a continuation and extension of our earlier work (X‐ray Spectrom. 2010 , 39, 127–134, DOI:10.1002/xrs.1215) on the development of a software platform CATGIXRF, as a solution to provide non‐destructive evaluation of nanostructured materials. Here, we describe an interactive graphical user interface (GUI) for the CATGIXRF program. The newly developed GUI interface facilitates determination of microstructural parameters on angstrom length scale for the nanostructured thin layered materials using synchrotron as well as laboratory X‐ray sources. It allows combined analysis capabilities for both the X‐ray reflectivity and grazing incidence X‐ray fluorescence (GIXRF) data simultaneously, thus enabling us a greater sensitivity for the determination of microstructural parameters such as thickness, interface mixing, and roughness of a thin film medium with improved accuracies. The utility and various newly added salient features of the GUI‐CATGIXRF program are described by providing example calculations as well as by analyzing experimentally a few thin film structures with different surface‐interface properties. Copyright © 2016 John Wiley & Sons, Ltd.     

基于GUI的空间滤波实验的计算机模拟

分析了空间滤波实验的原理,利用Matlab软件编写了带有图形用户界面(GUI)的计算机模拟程序.该程序能够准确模拟实际实验过程,在功能上还对其进行了扩充,对于提高空间滤波实验的教学效果起到很好作用.     

WIFIP: a web‐based user interface for automated synchrotron beamlines

The beamline control software, through the associated graphical user interface (GUI), is the user access point to the experiment, interacting with synchrotron beamline components and providing automated routines. FIP, the French beamline for the Investigation of Proteins, is a highly automatized macromolecular crystallography (MX) beamline at the European Synchrotron Radiation Facility. On such a beamline, a significant number of users choose to control their experiment remotely. This is often performed with a limited bandwidth and from a large choice of computers and operating systems. Furthermore, this has to be possible in a rapidly evolving experimental environment, where new developments have to be easily integrated. To face these challenges, a light, platform‐independent, control software and associated GUI are required. Here, WIFIP, a web‐based user interface developed at FIP, is described. Further than being the present FIP control interface, WIFIP is also a proof of concept for future MX control software.     

EPR and Optical Absorption Study of VO2+ Ions Doped Potassium Hexaaquazinc (II) Sulfate Single Crystals

X-band single-crystal electron paramagnetic resonance (EPR) studies are done on VO²⁺ ions doped in potassium hexaaquazinc (II) sulfate, K₂[Zn (H₂O)₆] (SO₄)₂ (PHZS) at room temperature. The spin Hamiltonian parameters, i.e., g and A tensors and their direction cosines, are evaluated by the standard diagonalization procedure using angular variation of the EPR spectra in three planes (ab, bc* and c*a), with the help of a computer program. The EPR spectrum is simulated using the EasySpin program to verify the calculations. The detailed EPR analysis indicates the presence of two magnetically inequivalent VO²⁺ sites. Both the vanadyl complexes are found to take up the substitutional position in the host lattice. The optical absorption spectrum of VO²⁺ ions doped in PHZS single crystal at room temperature is also recorded and four main d–d transfer bands in the visible region are assigned. The theoretical band positions are obtained using energy expressions and a good agreement is found with the experimental values. With the help of assigned bands the crystal-field parameters (Dq, Ds and Dt) are evaluated. Finally, with the optical and EPR data, the nature of bonding in the complex is discussed.     

Physical Optics Simulation in Matlab for High-Performance Systems

Two advanced optical system applications are implemented in a Matlab™ based simulation engine. The applications are aligning a micro-optic fiber coupler and scanning an optical disk with a readout system having an effective numerical aperture of 1.8. Many phenomena, like scalar diffraction, vector diffraction, addition of aberrations, thin-film interactions, and Babinet decomposition are described in the examples. A powerful graphical user interface (GUI) is also described that allows users to define optical elements, program operations and control program flow. Users can also easily interface custom field operations to the simulation engine.     

基于GUI的阿贝-波特滤波实验的计算机仿真

介绍了阿贝-波特空间滤波的实验原理,在Matlab环境下建立了带有图形用户界面（GUI）的计算机仿真平台.不仅可以准确地完成针对不同输入图像、不同滤波要求的滤波过程,还可以通过调整滤波器参数观察滤波效果的差异,形象地展现光学空间滤波过程的物理本质,提高教学效果.