高速公路桥梁混凝土防撞护栏质量通病及预防措施

桥梁混凝土防撞护栏作为桥梁外观质量的关键施工部位,因其自身的特点容易产生质量通病,从而影响整个桥梁美观。本文通过分析产生质量通病的原因,提出了相应的预防措施。     

国家体育场、国家游泳中心对比研究

2008北京奥运给土木工程领域注入了新的活力,也带了的新的挑战。国家体育场与国家游泳中心是奥运重要场馆,分别体现着不同的使用功能,代表着不同的结构形式,带有普遍性与特殊性,。就这两个场馆进行了对比,为其他大型场馆工程的设计提供了思路。     

居住区无障碍设计与残障人群特征

在居住区中,对无障碍设施有需求的人群,不仅包括传统意义上的残疾人,还应包括老年人、幼年儿童等对居住环境使用有困难的群体.因此,要科学地对残疾人、老年人和儿童的生理、心理、行为进行分析,寻找他们的特殊需求,为有针对性的无障碍设计做准备.     

C50机制砂高性能混凝土在白庙劳教所高层住宅转换层中的应用

根据工程设计特点结合当地原材料情况,采用机制砂配制C50高性能混凝土,并通过优化配合比设计及合理的施工方案,成功解决了该转换层的施工难点。     

锰氧化物负载沸石固定床离子交换柱去除铀(VI)的研究

The adsorption of uranium (VI) on the manganese oxide coated zeolite (MOCZ) from aqueous solution was investigated in a fixed-bed column. The experiments were conducted to investigate the effects of bed height, flow rate, particle size, initial concentration of uranium (VI), initial pH, presence of salt and competitive ions. The U-uptake by MOCZ increased with initial uranium (VI) concentration and bed height, but decreased as the flow rate and particle size increased. In the presence of salt and competitive ions, the breakthrough time was shorter. The ad-sorption capacity reached a maximum at pH of 6.3. The Thomas model was applied to the experimental data to de-termine the characteristic parameters of the column for process design using linear regression. The breakthrough curves calculated from the model were in good agreement with the experimental data. The BDST model was used to study the influence of bed height on the adsorption of uranium (VI). Desorption of uranium (VI) in the MOCZ column was investigated. The column could be used for at least four adsorption-desorption cycles using 0.1 mol•L－1 NaHCO3 solution as the elution. After desorption and regeneration with deionized water, MOCZ could be reused to adsorb uranium (VI) at a comparable capacity. Compared to raw zeolite, MOCZ showed better capacity for uranium (VI) removal.     

1,2-环氧环己烷与2-环己烯-1-酮的等压汽液平衡

Green oxidation of cyclohexene using dioxygen as oxidizing agent is highly desirable because of its environmental compatibility and economic impact. Separation of its oxidation products depends on the reliable vapor- liquid equilibrium (VLE) data of relevant components, which are still lacking. The VLE data of binary system 1,2-epoxycyclohexane and 2-cyclohexen-1-one under ambient pressure were obtained using an improved VLE equipment EC-2 still in this work. The results showed that this binary system has no azeotropic point. Furthermore, the experimental VLE data were correlated with the Wilson thermodynamic model and the corresponding binary interaction parameters of the model were obtained. The results showed that the VLE data agreed well with the model and passed the thermodynamic consistency test of Herrington.     

国内外低焦油烤烟型卷烟中性香味成分的分析比较

将国内外5种（国外1种,国内4种）低焦油烤烟型卷烟烟丝经同时蒸馏萃取、GC、GC／MS分析测试,对低焦油烤烟型卷烟烟丝29种中性香味成分进行了分析研究。国内外卷烟烟丝的常规化学成分也进行了测试比较。结果发现,国产烤烟型卷烟挥发性、半挥发性中性成分总量、酮类成分总量、醇类成分总量比国外烤烟型卷烟低,醛类成分总量、酯类成分总量比国外高。4种国产烤烟型卷烟烟丝重要中性香味成分中均比国外烤烟型卷烟低10％以上的有：苯乙醛、糠醇、苯甲醇、六氢金合欢基丙酮和2-甲氧基4-乙烯基苯酚;均高于10％的有：糠醛、亚麻酸甲酯等。     

VOX-XG全数字光纤视频传输交换平台在高速公路上的应用

VOX-XG系统将视频、音频、计算机网络、数据等统一到同一的传输平台中,提供了丰富的业务接口,如Ethernet、E1、RS232/RS485/RS422、开关量、语音等,并且创造性地将分布式数字视频矩阵纳入到该平台中。     

一种移动IPv6下防火墙技术的研究与实现

随着计算机网络在政治、经济、文化等诸多方面的飞速发展,网络安全技术也越来越受到前所未有的重视。本文针对移动节点在外地网络与家乡网络通信的透明性,以及传输的安全性问题,设计了一种对防火墙和移动节点之间的通信进行IPSEC信息验证的方法,解决了移动IPv6下移动节点在外地网络与家乡网络通信穿越防火墙的问题。     

使用McAfee企业版的访问保护加固服务器安全

随着计算机技术的迅猛发展,操作系统的功能也越来越强、越来越人性化,但伴随着的是越来越多的漏洞的出现,现有的防黑技术和防病毒技术已经捉襟见肘,McAfee企业版针对这种现象引入了主机入侵防御体系,为服务器的安全提供了有力的保障。