Editor’s note

The past two decades have witnessed great progress in development of ultrashort laser pulse in laser science, often at an unexpected speed. It has found various applications, both theoretical and practical, in the frontiers of science.     

Carbonaceous particles in Muztagh Ata ice core,West Kunlun Mountains,China

Carbonaceous particles concentrations of OC and EC are determined using a two-step gas chroma- tography system in Muztagh Ata ice core covering the time period of 1955--2000. Over the period represented by the core, OC and EC concentrations appear to have changed significantly, varied in the range of 17.7--216.7 and 6.5--124.6, and averaged 61.8, 32.9 ng·g^-1, respectively. The average concentration of EC in Muztagh Ata ice core is much lower than that in an Alpine ice core record （100--300 ng·g^-1） during the same period, but it is a factor of 14 in Greenland ice core （2.3 ng·g^-1）, this may induce a strong impact on the snow albedo in the last 46 years in our study area. Observations indicate two periods with obviously high deposition concentrations （1955--1965 and 1974--1989） and two periods with low concentrations （1966--1973 and 1990--1995）, as well as a recent increasing trend. By comparing EC and SO4^2- concentration variations and deciphering OC/EC ratios recorded in the same ice core, we can judge roughly that the carbonaceous particles deposited in Muztagh Ata ice core were attributed to fossil fuel combustion sources.     

Effective identification of the three particle modes generated during pulverized coal combustion

Based on the mass fraction size distribution of aluminum （AI）, an improved method for effectively identifying the modes of particulate matter from pulverized coal combustion is proposed in this study. It is found that the particle size distributions of coal-derived particulate matter actually have three modes, rather than just mere two. The ultrafine mode is mainly generated through the vaporization and condensation processes. The coarse mode is primarily formed by the coalescence of molten minerals, while the newly-found central mode is attributed to the heterogeneous condensation or adsorption of vaporized species on fine residual ash particles. The detailed investigation of the mass fraction size distribution of sulfur （S） further demonstrates the rationality and effectiveness of the mass fraction size distribution of the AI in identifying three particle modes. The results show that not only can the number of particle modes be identified in the mass fraction size distributions of the AI but also can their size boundaries be more accurately defined. This method provides new insights in elucidating particle formation mechanisms and their physico-chemical characteristics.     

自主需要在教练行为与大学生运动员内在动机间的中介效应

研究教练领导行为与运动员内在动机之间的关系,以及教练领导行为的作用机制,即教练领导行为是否会通过运动员能力感知、自主性、关系感影响大学生运动员内在动机.运用对282份大学生运动员调查问卷的结果,采用结构方程模型技术对教练领导行为、内在动机、能力感知、自主性、关系感之间的关系进行了验证分析.结果表明,自主性和关系感对教练领导行为与运动员内在动机的关系具有一定的中介作用.     

从人才视角浅谈对电子商务专业教学方法的研究

文章结合当前电子商务毕业生就业难的现状,在指出当前高校电子商务专业教学存在问题的基础上,作者结合自己的教学实践提出了几种教学方法,并分别对各教学方法的实施以及在人才培养中所体现出来的优势进行了初步探讨。     

对艺术类院校女生健美操课的几点思考

本文通过对艺术类院校女生的生理现状和健美操专项课程的学习现状健的分析,对健美操课的教师应具备的素质、音乐的选择、课堂组织形式、运动强度、密度、间歇时间,课程安排次数、教学内容、考核办法、考勤制度等方面进行探讨。提出了怎样上好艺术类院校女生健美操课的建议。     

刍议高校教师激励机制体系的构建

从剖析现行激励机制存在的主要缺陷入手,分析了影响高校教师激励机制发展的因素,探讨了高校教师激励机制体系的构建对策。     

一类非线性算子方程的迭代求解

利用锥理论和半序理论研究Banach空间中的非线性算子方程解的存在惟一性问题．改进和推广了某些已知结果．     

基于Struts构架的企业Web管理信息系统模式研究

文章首先介绍了B/S三层客户/服务器结构,并分析了XM L和三层客户/服务器的有关技术,在此基础上提出了一种新的企业信息系统集成解决方案：用B/S三层客户/服务器搭建企业信息系统的动态集成.最后以实际的案例对该模型进行了简单的分析.