以Rh催化费托合成为例简述微观动力学在物理化学教学中的应用*

借助Rh催化费托合成反应,探讨了微观动力学模拟软件MKMCXX在物理化学化学动力学章节教学中的应用。以密度泛函理论(DFT)计算的能垒和反应热为基础,通过MKMCXX软件构建微观动力学模型,计算各中间物种的表面覆盖度、反应速率、反应级数与表观活化能,使学生能够直观地理解化学动力学。     

Lightweight object oriented structure analysis: Tools for building tools to analyze molecular dynamics simulations

LOOS (Lightweight Object Oriented Structure‐analysis) is a C++ library designed to facilitate making novel tools for analyzing molecular dynamics simulations by abstracting out the repetitive tasks, allowing developers to focus on the scientifically relevant part of the problem. LOOS supports input using the native file formats of most common biomolecular simulation packages, including CHARMM, NAMD, Amber, Tinker, and Gromacs. A dynamic atom selection language based on the C expression syntax is included and is easily accessible to the tool‐writer. In addition, LOOS is bundled with over 140 prebuilt tools, including suites of tools for analyzing simulation convergence, three‐dimensional histograms, and elastic network models. Through modern C++ design, LOOS is both simple to develop with (requiring knowledge of only four core classes and a few utility functions) and is easily extensible. A python interface to the core classes is also provided, further facilitating tool development. © 2014 Wiley Periodicals, Inc.     

New implementation of high‐level correlated methods using a general block tensor library for high‐performance electronic structure calculations

This article presents an open‐source object‐oriented C++ library of classes and routines to perform tensor algebra. The primary purpose of the library is to enable post‐Hartree–Fock electronic structure methods; however, the code is general enough to be applicable in other areas of physical and computational sciences. The library supports tensors of arbitrary order (dimensionality), size, and symmetry. Implemented data structures and algorithms operate on large tensors by splitting them into smaller blocks, storing them both in core memory and in files on disk, and applying divide‐and‐conquer‐type parallel algorithms to perform tensor algebra. The library offers a set of general tensor symmetry algorithms and a full implementation of tensor symmetries typically found in electronic structure theory: permutational, spin, and molecular point group symmetry. The Q‐Chem electronic structure software uses this library to drive coupled‐cluster, equation‐of‐motion, and algebraic‐diagrammatic construction methods. © 2013 Wiley Periodicals, Inc.     

SPSS软件对铁矿中微量元素含量的统计分析

利用SPSS软件从统计学描述、正态分布检验、回归和相关分析、聚类分析和因子分析等方面对铁矿中微量元素含量特点进行了研究。分析结果表明:根据抽样样本,铁矿中11种微量元素含量均不符合正态分布特征,异常值分布矿种相对集中,重金属和硫及卤素之间的相关程度高,同时根据因子综合得分对矿种进行了分类,为铁矿品质评价和合理利用提供了一定的参考。     

基于电磁兼容设计的光电设备接地问题浅析

接地设计是光电设备电磁兼容设计的重要组成部分,好的接地能够保护设备和人身的安全,保证光电设备正常可靠工作。地线造成电磁干扰的主要原因是它具有阻抗和感抗特性,这些特性在某些情况下会导致地环路干扰和公共阻抗耦合等电磁骚扰。从地线的特性出发分析地线干扰的成因,提出抑制地线干扰,提高电路电磁兼容性的方法。     

SOAS: A free program to analyze electrochemical data and other one-dimensional signals

This paper describes an open source program called SOAS, which we developed with the aim of analysing one-dimensional signals. It offers a large set of commands for handling voltammetric and chronoamperometric data, including smoothing signals, differentiation, subtracting baselines, fitting current responses, measuring limiting currents, and searching for peak positions. Although emphasis is on the analysis of electrochemical signals, particularly protein film voltammetry data, SOAS may also prove useful for processing spectra. This free program is available by download from the Internet, and can be installed on computers running any flavor of Unix or Linux, most easily on MacOS X.     

Reduction in pressure drop for pipe flow due to applied electric potentials to the pipe

For all forms of transport of fluids in pipes, there is loss of pressure due to the friction. It has been shown that an electrical potential applied to the pipe wall can reduce water flow friction. Piezometric pressure loss over the 13.1 m slanting epoxy coated pipe made of steel, through which water was flowing, decreased when pipe was exposed to positive DC-potentials in the range 0.6–1.6 V. Maximum reduction was 2% with an applied potential of 1.0 V. Results from full scale experiments in a hydroelectric power plant (12.5 MW, 85 GWh) show that head loss decreased from 45.9 m to 39.8 m at maximum flow rate after 2.5 years of exposure to 1.1 V. Similar results for the head loss in another power plant (28 MW, 116 GWh) were 17.5 and 17.2 m, respectively, after 9 months of exposure to this DC-potential. The positive polarization of the pipes was noticeable throughout the whole length of the pipe. Published in Russian in Elektrokhimiya, 2008, Vol. 44, No. 5, pp. 649–656. The text was submitted by the authors in English. The paper was prepared for special issue devoted to V.G. Levich 90th anniversary.     

房地产项目整体定位与经济评价

在市场经济条件下我国房地产业进人快速、稳定的发展阶段，新世纪中国房地产行业面临极为难得的发展机遇，如何在竞争日趋激烈的情况下规避风险，提高利润率，实现项目的利润最大化，是我国房地产业能否持续、健康、稳定发展的重大问题之一。房地产项目策划能有效整合房地产项目资源，探索解决企业发展中的问题，增强企业的管理创新能力。本文为了实现项目经济效益、社会效益、环境效益的目标设定，科学地运用了房地产项目策划理论体系，探讨了房地产项目策划的作用、方体体系和运作程序，并运用于合肥某项目的工程实践中，得到房地产项目策划的一些经验和结论，为以后相关方面的理论研究和实践活动提供了借鉴和参考。     

线性方程组的多维投影算法

本文分析了求解线性方程组的一维投影算法即最小剩余法。定义了长轴陷阱及陷阱深度，用它们刻划了该算法迭代过程中锯齿现象的几何特征。本文给出了基于残差序列的避开长轴陷阱的扰动技巧，即多维投影算法。数值试验表明，投影算法要优于现在流行的主要算法。