Hydrogen Permeation and Diffusion in Amorphous Alloy Ni_(68)Cr7_Si_8B_(14)Fe_3 at Elevated Temperature

The behaviour of hydrogen permeation and diffusion in amorphous alloy Ni68Cr7Si8B14Fe3 hasbeen investigated by an ultrahigh vacuum gas permeation technique. A comparison experimentwas carried out between the as-quenched and annealed States (400℃/2h) of the amorphousalloy. The results show that, for both states of the amorphous alloy in the temperature rangeof 200～350℃, the diffusivity and permeability of hydrogen are in agreement with Arrheniusrelationship, there does not exist H-trapping effect, and the activation energies of diffusion andpermeation almost keep the same.     

ATM网络的可用比特率业务

本文介绍了可用比特率业务的业务特点，速率控制机制以及该业务存在的问题。     

Incremental iron overload during reperfusion progressively augments oxidative injury

OBJECTIVE: To determine if a relationship exists between the extent of iron-catalyzed injury and the degree of tissue iron overload during reperfusion. METHODS: To selectively increase tissue iron only during early reperfusion, isolated, buffer perfused rabbit hearts were exposed to 20 microM Fe(2+)-100 microM ADP during the last 3 minutes of ischemia and the initial 4 minutes of reperfusion. Control groups were exposed to ADP and iron-ADP regimens that did not increase intracellular iron. All the hearts received 30 minutes of normothermic global ischemia and 30 minutes of reperfusion. Heart function was monitored continuously throughout each experiment. Tissue iron and biochemical markers were analyzed at the end of experiments. RESULTS: Hemodynamic recovery was decreased and tissue lipid peroxide levels were increased in the 20 microM Fe(2+)-100 microM ADP group compared to controls. The recoveries of developed pressure and positive/negative dP/dT at 30 minutes of reperfusion were negatively correlated with tissue iron levels, while cytosol and membrane lipid peroxide levels correlated positively with the iron levels during reperfusion. CONCLUSION: The extent of oxidative injury during reperfusion was directly related to the tissue iron burden present during reperfusion. Increased lipid peroxidation was the principal chemical marker of iron-catalyzed injury.     

建材研究的新热点——黄河淤泥沙综合利用进展及前景展望

简要介绍了黄河淤泥沙的特性及相关情况,论述了黄河於泥综合利用研究的进展及主要成果,概述了其工业化开发的现状,分析了其存在的问题,对其发展前景进行了预测。黄河淤泥沙综合利用工作是关系到国计民生、千秋万代的大事,具有重要的现实意义和深远的历史意义。     

虚拟企业图纸数据传输

图纸数据是企业间合作需交换的一种重要的信息。本文分析了虚拟企业环境下企业之间交换图纸数据的要求，提出了一种具体的解决方案，并给出实例。     

高温超导研究的新进展

本文简要回顾了一年来高温超导的新进展，特别介绍和讨论了新型高温超导体系和线材、带材、块材及薄膜应用的发展情况。     

强度调制／直接检测（IM／DD）光纤通信系统色散限制的研究

通过引入归一化脉宽Ｐ和相对脉冲展宽因子ｑ，提出了一个适用于ＩＭ／ＤＤ系统中各种眼图恶化量ｘ和归一化脉宽Ｐ的色散限制改进公式。通过与其它理论的比较、计算机仿真和对实验数据的分析，验证了该公式的正确性，并给出了其它结果的限制条件。研究表明：当眼图恶化量ｘ为１ｄＢ左右时，对２．５Ｇｂ／；外调制信号（α＝０）而言，非色散位移光纤ＩＭ／ＤＤ系统的色散因子γ约等于０．７９，所对应的系统再生中继距离约为９００余公里。     

开放、交流与凝聚--广州大学城广外学生活动中心设计

2003年夏天，广州大学城广州外语外贸大学一期项目的单体设计在相当短的设计周期中紧张地铺开。     

石膏矿床冲击地压灾害形成原因及其防范

以往认为金属矿山开采深度超过500m、煤矿山开采深度超过200m时，应关注冲击地压问题。通过对石膏矿床冲击地压的灾害调查，表明石膏矿开采深度在150m以内都存在冲击地压、冒顶等事故隐患。根据调查情况，分析了冲击地压形成的地理条件及造成冲击压灾害的有关开采技术与管理等因素，并介绍了灾害的预测与预防措施。     

论现行行政事业单位财务会计制度和现实会计处理的矛盾

随着我国市场经济的发展与管理体制的不断改革，财会管理制度相对落后于现实工作要求，使实际工作缺乏相关规范性的指导。本文从实践出发，在分析了这一规则与实务间的矛盾后，提出对行政事业单位财务规则及会计制度的几项修改建议。