平衡纵剖面数值试验及其对防洪的影响研究

本文采用一维非恒定流非均匀沙的水沙数学模型，以长江中游螺山汉口河段为背景，进行了根化数值模拟试验，分析了该概化河段平衡纵剖面的变化规律及其与上游来水来沙条件的关系，并和相应的理论公式进行了比较。在此基础上，对水沙条件发生较在变化时的平衡纵比降以及带来的对长江中下游防洪的影响进行了分析。     

Parathion degradation and toxicity reduction in solar photocatalysis and photolysis.

The solar photocatalytic degradation of methyl parathion was investigated using a circulating TiO2/solar light reactor. Under solar photocatalysis condition, parathion was more effectively degraded than solar photolysis and TiO2-only conditions. With solar photocatalysis, 20 mg/L of parathion was completely degraded within 60 min with a TOC decrease of 63% after 150 min. The main ionic byproducts during photocatalysis recovered from parathion degradation were mainly as NO3-, NO2- and NH4+, 80% of the sulphur as SO4(2-), and 5% of phosphorus as PO4(3-). The organic intermediates 4-nitrophenol and methyl paraoxon were also identified, and these were further degraded in solar photocatalytic condition. Two different bioassays (Vibrio fischeri and Daphnia magna) were used to test the acute toxicity of solutions treated by solar photocatalysis and photolysis. The Microtox test using V. fischeri showed that the toxicity expressed as EC50 (%) value increased from 5.5% to >82% in solar photocatalysis, indicating that the treated solution is non-toxic, but only increased from 4.9 to 20.5% after 150 min in solar photolysis. The acute toxicity test using D. magna showed that EC50 (%) increased from 0.05 to 1.08% under solar photocatalysis, but only increased to 0.12% after 150 min with solar photolysis, indicating the solution is still toxic. The pattern of toxicity reduction parallels the decrease in TOC and the parathion concentrations.     

贯彻钢铁产业政策走科学发展之路

时光荏苒，钢铁行业不知不觉又沐浴在2006年的春光之中。从2004年以来国家陆续出台宏观调控政策，到2006年年初的平衡过渡，钢铁行业跨越了由风声鹤唳到有惊无险的历程。     

Continuous extension of preferences

We consider the problem of extending preferences from a subset of a commodity space to the entire space. It is a simple consequence of the Tietze extension theorem that continuous preferences can be extended if they are defined on closed subsets of a normal space and are representable by utility functions. We show the following: If the space is a non-separable metric space, then extension of preferences is not always possible. In fact for (path-connected) metric spaces, extension property, utility representation property, and separability are equivalent to each other.     

会计网络化建设存在的问题与对策

会计网络化是会计发展的必然趋势。加快会计网络化建设有利于拓宽财务管理的空间,加快业务流程的时效,提升财务管理的效能,确保资金划拨安全快捷。目前,会计网络化建设在规划设计、功能开发和运行管理等方面,存在重建轻联、重投轻用、重有轻管、重硬轻软等问题。本文中笔者从五个方面剖析会计网络化建设存在问题的原因,在此基础上,从加强统一领导,重视整体设计,完善管理机制,强化管理职能四个方面来提出有针对性的改革措施。     

面向对象程序设计教学改革与实践

指出了面向对象程序设计教学中存在的问题,针对问题提出了改革措施：采用案例式教学,加强实践教学管理,结合BB教学平台辅助教学。不断提高学生学习的自觉性和主动性,成为教学改革的重要研究内容。     

试论建立和完善我国矿产资源有偿使用制度

文章介绍了典型市场经济国家为实行矿产资源有偿使用而向矿产资源使用者征收的费税种类.同时介绍了我国向矿产资源使用者征收的六种税费,并指出了其缺陷和不足之处,在此基础上,提出了对我国矿产资源税费进行改革可供选择的三个方案.     

基于知识约简的企业员工知识培训决策研究

文章首先阐述企业员工知识培训的重要性,指出企业对员工进行知识培训管理方面的不足,认为要有效地进行知识培训,必须首先了解员工的知识缺失,进行科学的知识需求分析.文章在介绍知识约简的相关概念基础上.提出了基于知识约简的企业员工知识培训决策的方法步骤,并结合算例进行了具体分析.     

供应链管理模式下零库存理论及其在企业中的应用

主要分析了影响企业库存管理的因素，介绍了实现企业零库存的主要方法，针对目前国内企业的库存现状，提出了实现零库存的库存控制理论、实施方法和途径及在实现过程中应注意的问题。     

我国实现高科技产业化的战略与对策

文章重新审视了影响和推动人类文明可持续发展的高科技产业化浪潮 ,从知识经济、技术创新、市场经济的不同角度描述了高科技产业的全新面貌和本质特征。在此基础上 ,从新亮点、新支点和新焦点诸方面设计了中国高科技产业化平台 :高科技产业的市场化。