土石坝溃决机理模型试验研究进展

大坝溃决将给人类社会带来巨大的灾难,因此国内外都很关注溃坝问题的研究。由于多数大坝均为土石坝,且土石坝是逐渐溃决的过程,而混凝土坝一般表现为瞬时溃决,因此土石坝溃决机理与溃决过程的研究对于溃坝过程数学模型的建立和致灾后果的评价具有重要的指导意义。自20世纪90年代以来,国内外学者围绕土石坝溃决机理开展了广泛深入的模型试验研究,取得了一系列重要的研究成果。分别从土石坝溃决原因、土石坝溃决机理研究进展、土石坝漫顶溃决模型试验、土石坝管涌溃决模型试验等方面介绍国内外的研究进展。重点针对土石坝坝型(均质坝、黏性心墙坝、面板堆石坝)和主要破坏模式(漫顶溃坝与管涌溃坝),介绍国内外开展的不同尺度的溃坝模型试验,分析研究了土石坝的溃决机理,并对今后的研究工作重点提出了相关建议。     

贝叶斯(Bayes)判别分析理论在安全评价中的应用

论述了多元统计分析方法中的贝叶斯判别分析方法在安全评价中的应用。通过对原始数据的分析建立起反映被评价对象安全状况的综合指标函数模型,从而简化后续同类评价目标工作量。     

Synthesis of Succinylated Starches and Their Application as Adsorbents for the Removal of Phenol

Journal of Polymers and the Environment - Succinylated starches (SS) were prepared by the reaction of normal starch (NS) and porous starch (PS) with succinic anhydride (SA) in the presence of DMF...     

TiO2投加量及其表面载银量对光催化降解Aro-clor1260的影响

在紫外灯照射下,催化剂TiO₂的投入量及其表面载银量对光催化降解Aroclor1260有显著的影响.但TiO₂的投入量并不与Aroclor1260的降解速率成正比关系,而是有一个最佳投入量,在本文的实验条件下,这个最佳值为60mg(3g/L).TiO2的表面载银量越多,Aroclor1260的降解速率也越大,而且浓度相对较高的PCB单体化合物的降解速率大于浓度相对较低的PCB单体化合物的降解速率.对于多数PCB单体化合物而言,TiO₂的催化活性随其表面载银量的增加而增强.     

武警森林灭火作战防护鞋的设计与开发

森林火灾的灭火有一定的特性。森林灭火作战需要徒步靠近火场，有时甚至要经过几十个小时的艰苦跋涉才能到达目的地。由于每一个单兵就是一个战斗的主体，而恶劣的自然环境又对装备提出特殊要求，因此，为减轻单兵负荷。作战防护鞋应穿着轻便、舒适，适合长途行军，并具有良好的阻燃性能。     

石墨炉原子吸收法测定土壤金属元素的质量控制

为使石墨炉原子吸收法测金属元素准确可靠，对各测定程序和环节采取了消除干扰、测平行双样、测加标回收率、对照分析等措施。测定数据经统计分析，加标回收率在87．3％～115．2％范围内，平行双样相对偏差在12．3％以下，标准土样重复测定变异系数除镉（Cd）外均在5．9％以下，达到了分析测定的要求。     

Air quality assessment for land disposal of industrial wastes

Air pollution from hazardous waste landfills and lagoons is largely unknown. Routine monitoring of toxic air contaminants associated with hazardous waste facilities is difficult and very costly. The method presented in this paper would be useful for air quality assessment in the absence of monitoring data. It may be used as a screening process to examine the question of whether or not volatilization is considered to be significant for a given contaminant and also to evaluate permit applications for new hazardous waste facilities concerning waste volatilization problems.     

旋转射流破岩钻孔机理研究

综合利用实验方法和数值模拟技术,研究了旋转射流的结构特性及井底流场分布,证明了旋转射流具有三维速度,且其速度最高部分,集中在离开射流轴心一定半径的一环形区域上,射流呈扩散状,其冲击面积随喷距的增大而大幅度增加。旋转射流破岩钻孔的机理不同于普通圆射流,它以剪切破碎为主,伴以冲蚀、拉伸破坏和磨削等多种形式,因而具有很高的破岩效率。破岩首先从对应着射流能量最高的环形区域开始,并逐步向内、外扩展,形成凸锥状的孔底。研究表明旋转射流在破岩钻长连续孔眼方面具有极大的优势     

出舱活动过程中航天员的热舒适性分析

分析了出舱活动中航天员－ 服装系统的热平衡,阐述了影响航天员热舒适性的因素及热舒适性的评价标准,并对美国航天员舱外活动的冷应激的人体工程学问题进行了讨论。还指出了提高航天员热舒适性有待解决的几个关键问题。     

Air pollution assessment of toxic emissions from hazardous waste lagoons and landfills

The air quality impacts of hazardous waste disposal sites can be assessed on the basis of their contribution to each of the toxic contaminants. The purpose of this paper is to discuss the available methods of air quality assessment and their drawbacks. The need of air quality assessment is to assure that ambient concentrations of specific contaminants resulting from emissions will not exceed the acceptable levels for protection of public health and the ecosystem. Ambient concentrations of toxic contaminants are generally obtained by field measurements or air monitoring. However, field measurements and air monitoring of low-level toxic contaminants are costly and time consuming. As a result, most hazardous waste land disposal sites have not been adequately assessed. This paper describes current regulatory requirements in the United States for air quality assessment of hazardous waste land disposal sites. Emphasis is directed toward air quality assessment methodology. The paper also discusses emission predicting models based on the waste quantity and composition, scientific analysis of the waste conversion process together with meteorological conditions. The emission models are especially useful where emission cannot be reliably monitored or where a new disposal site is proposed.