中国公路建设项目环境保护管理综述

综述了中国公路建没项目环境保护管理的有关规定，包括环境保护管理的内容与程序、分类管理、环境影响评价市批与环境影响咨洵收费管理等。     

煤飞灰中铬铁元素的形态分析研究

用连续提取法将煤飞灰中的铬、铁元素依结合态区分为水溶态,交换态,表面氧化物和碳酸结合态,铁锰氧化物结合态,金属有机物和硫化物结合态,磁性四氧化三铁结合态和硅铝酸盐矿物态,用原子吸收法及X-衍射分析进行测定。并对煤飞灰化学形态分布进行了讨论。     

武钢金山店铁矿某通风系统项目评估

介绍了金山店铁矿通风系统多级站和机站设计；阐述了该项目的施工，检测及通风效果评估情况；对安全生产提出了全面，系统的建议。     

小径薄壁管射线透照布置方法

小径薄壁管广泛用于工艺管道中，在对其进行无损探伤时，一般采用双壁双影椭圆成像法和双壁重叠成像法，针对小径薄壁管对接焊缝透照成像的特殊要求，具体介绍双壁双影椭圆成像法的透照布置方法。     

液化石油气罐区火灾爆炸危险性评价

液化石油气罐区属于重大危险源,一旦发生火灾爆炸事故,后果非常严重.评价其安全性,控制其危险,是重大事故预防的思想,也是国家安全生产法律、法规的强制要求.笔者根据安全工程学的相关原理,综合运用重大危险源评价法和灰色聚类法分别对罐区的固有危险性和现实危险性进行了评价,克服了重大危险性评价法未考虑环境因素这一缺陷,最后得出了其火灾爆炸危险性等级,为政府监管和企业对危险源的监控管理提供了可行的科学依据.     

Dynamic Bayesian networks for reliability evaluation of subsea wellhead connector during service life based on Monte Carlo method

The subsea wellhead connector is a critical connection component between subsea Christmas tree and subsea wellhead for preventing the leakage of oil and gas in the subsea production system. Excited by cyclical loadings due to environmental forces and the other support forces, the subsea wellhead connector is prone to the failure, which could lead to the loss of subsea tree or wellhead integrity and even catastrophic accidents. With the Monte Carlo simulation method, this paper presents a reliability analysis approach based on dynamic Bayesian Networks, aiming to assess the failure probability of the subsea wellhead connector during service life. Take the driving ring component of the subsea wellhead connector as an example to demonstrate the reasonability of the proposed model. The generation data is processed by the transform between the numerical value and the state variable. Based on the stress-strength interference theory, the structure reliability of the driving ring with 96.26% is achieved by the proposed model with the consideration the aging of the material strength and the most influential factors are figured out. Meanwhile, the corresponding control measures are proposed effectively reduce the failure risk of the subsea wellhead connector during service life.     

机载武器及其双配套设备可靠性鉴定试验方案的分析

通过分析机载武器的使用特点和情况,并结合实验室开展机载武器可靠性鉴定试验的已有经验,对该类装备的可靠性鉴定试验的方案进行了分析和讨论,对试验样件在充足或不足的条件下进行试验的各种试验方案进行了深入分析。指出了各种方案的优缺点,对比了各种试验方案的特点。最后给出了机载武器可靠性鉴定统计试验方案的选取原则。     

基于蒙特卡罗模拟的土壤环境健康风险评价:以PAHs为例

为获得更为合理的健康风险评价结果,并辨识对健康风险影响最大的因素,基于蒙特卡罗随机模拟,运用概率风险评价模型,定量评估了中国上海某居民区土壤中16种PAHs对居民的健康风险水平,并对各参数进行敏感性分析.结果表明,土壤中PAHs造成的健康风险服从对数正态分布,总的致癌风险为3.43×10~(-5)±2.63×10~(-5),最小值为8.10×10~(-7),最大值为2.39×10~(-4),超过10-6的概率为95%,超过10~(-5)的概率为75%,超过10~(-4)的概率小于5%;总的危害商为4.74×10~(-2)±3.42×10~(-2),不超过1,风险较小;在7种具有致癌效应的PAHs中,苯并(a)芘、二苯并(a,h)蒽和苯并(a)蒽是总致癌风险的主要贡献物质,贡献率分别占60.41%、26.84%和6.56%;3种暴露途径中,经口途径是造成致癌风险的主要途径,贡献率为73.22%;对于总致癌风险,人体暴露参数中每日土壤摄入量、暴露周期、暴露皮肤面积敏感度较大,分别为58.35%、50.21%和20.51%;体重具有负敏感性,敏感度为-11.66%.     

Development of a biaxial loading frame for sheet metal

Characterization of the evolving yield loci and forming limit diagrams for sheet materials under biaxial loading is necessary for the development of accurate sheet metal forming process simulations. Biaxial tension testing has been shown to have significant advantages over the current computational and experimental methods for such material characterization; however, the few commercially available loading frames are far too large and expensive to be practical for most metal forming research laboratories. In this paper, the design of a practical servohydraulic biaxial loading frame is presented. The design, control, and operation of the loading frame are discussed in detail, and experimental data is provided to validate the effectiveness of the control system with respect to specimen center shifting.     

水质氨氮在线监测仪发展现状

水中氨氮作为"十二五"国家重点控制污染指标,其在线监测设备的发展至关重要,本文主要介绍了目前中国市场上存在的主要水质氨氮在线监测仪的原理情况,并按照国家标准对其进行基本性能和实际水样测试的比较试验,为水质氨氮在线监测仪的应用提供参考。