Increased fire hazard of N-heterocyclic compounds substituted by S-containing group

Release of CS₂ and/or H₂S caused by friction is demonstrated on two N-heterocyclic compounds carrying S-atom containing substituents. Because of the generation of electrostatic charge and creeping discharge, simultaneously brought about by friction, ignition and possible explosion of the released gaseous products of decomposition could occur. The tested compounds proved not to be sensitive to impact. Nonetheless, fire and explosion hazard of dusts must not be judged by their sensitivity to impact only. It is necessary to test their sensitivity to friction as well.     

严寒地区节能建筑外墙外保温施工方法优选

节能能源是我国的基本国策,建筑节能是我国节能工作的一个重要领域。严寒地区建筑物墙体节能是建筑节能的关键,而选择一种在严寒地区适用的墙体保温的施工方法显得尤为重要。文章将层次分析与模糊综合评判法引入到节能建筑外墙外保温施工方法优选中,在对节能建筑外墙保温要素分析的基础上,建立了施工方案优选的递阶层次结构,通过判断矩阵计算出层次总排序的权向量,并运用模糊综合评判模型优选出最佳方案。     

现浇混凝土外墙外保温有网体系的应用

高层民用建筑现浇混凝土外墙保温体系分有网体系与无网体系,其中有网体系是技术性较强的一种外墙外保温体系。介绍了有网体系的技术应用,以期让更多的工程技术人员认识它,从而更好地应用它。     

Use of DIPPR data in reactive chemical hazard assessment

In the early 1970's AIChE established the concept of Design Institutes. These are cooperative, industrially sponsored research efforts based on getting work done in an area of general interest at low cost to supporters. There are now four active AIChE groups. These are, with date of organization: Design Institute for Physical Property Data (DIPPR), 1978; Research Institute for Food Engineering (RIFE), 1984; Center for Chemical Process Safety (CCPS), 1985; and Center for Waste Reduction Technologies (CWRT), 1989. A fifth, Design Institute for Emergency Relief Systems (DIERS) has completed its work and established a user's group. The subject of this paper, DIPPR, is now in its eleventh year of funded project work. A symposium honoring the completion of DIPPR's tenth year was held in San Francisco in November, 1989. There were 11 papers presented, along with an historical overview. Copies of the 11 papers are available from the Engineering Societies Library in New York City, as Session 40. The papers were published as an AIChE Symposium Series in 1990 [1]. The DIPPR project results that can be used in reactive chemical hazard assessment are highlighted.     

基于层次分析法的高层建筑施工现场火灾风险模糊评价

针对高层建筑施工现场的火灾风险评价问题,在对各因素相互关系进行分析的基础上,通过层次分析法建立了由防火能力、灭火能力、疏散逃生能力和消防安全管理四大子系统组成的火灾风险评价指标体系,确定了指标体系内各因素的权值分配,得到了针对高层建筑施工现场的火灾风险评价模型。运用模糊综合评价方法对实际工程进行评价,根据最大隶属度原则确定了该工程的火灾风险等级。通过对评价结果的分析,找出了高层建筑施工现场存在的火灾隐患以及消防安全管理薄弱环节,提出了改进对策,指导施工人员有效控制施工中的不安全因素,减少施工中火灾事故的发生。     

Guidelines for hazard evaluation procedures: Second edition

This article presents an abstract of important additions and revisions to the Guidelines for Hazard Evaluation Procedures published by CCPS in 1985. It includes:

• An outline of the background and purpose of the project
• An overview of the importance of hazard identification and evaluation studies, including benefits and limitations
• An overview of the new chapters
• Discussion of Hazard Identification Methods and results

     

Documentation of hazard and operability studies

The recently enacted Clean Air Act Amendments of 1990 [1] and the proposed OSHA Process Safety Management Standard [2] both require that hazard evaluations be completed on all facilities that handle hazardous chemicals. Reports of the hazard evaluations must be kept on file and will be subject to inspection during an OSHA compliance audit. This paper outlines those concepts that are important in the preparation of the documentation of a Hazards and Operability (HAZOP) study.     

Moral hazard in repeated procurement of services

This paper analyzes repeated procurement of services as a two period model with a potential repeated agency relationship. In the first period, there is an incumbent who provides a service. In the second period, there is a contest stage in which the principal selects the next service provider. The agents’ effort is non-contractible and the contest stage is the mechanism to mitigate potential moral hazard problems. The principal takes account of the past service effort in the contest stage by choosing the weight of past effort and the degree of substitutability between past and current efforts. The results show that, when the principal does not value contest effort, considering past effort as the relevant effort in the contest is optimal. When the principal values contest effort and effort cost increases, decreasing substitutability between efforts is optimal.     

Functional requirements and design criteria for the design of high hazard containment laboratories

A brief overview of the design process which has been successfully utilized in planning a high hazard containment laboratory.     

除险加固措施在苏库恰克水库中的应用

本文对苏库恰克水库存在的病险情及产生的原因进行了分析,针对问题提出了加固的措施,以供其他平原水库土坝除险加固工程措施方案选择时参考和借鉴.     

The moral hazard of Lax FCC land use oversight for advanced network infrastructure

This article discusses issues that arise when service providers place network equipment on publicly owned lands in the United States. Based on land use policy at the Federal Communications Commission, this paper theorizes that the use of public lands for 5G network development will create a moral hazard, as service providers may be tempted to take risks in the way they use public lands. Per economic theory the firm could behave recklessly when knowing that the costs will be borne by someone else – in this case local citizens. This is an example of the moral hazard problem in economics.     

Comparative judgement for assessment

Historically speaking, students were judged long before they were marked. The tradition of marking, or scoring, pieces of work students offer for assessment is little more than two centuries old, and was introduced mainly to cope with specific problems arising from the growth in the numbers graduating from universities as the industrial revolution progressed. This paper describes the principles behind the method of Comparative Judgement, and in particular Adaptive Comparative Judgement, a technique borrowed from psychophysics which is able to generate extremely reliable results for educational assessment, and which is based on the kind of holistic evaluation that we assume was the basis for judgement in pre-marking days, and that the users of assessment results expect our assessment schemes to capture.     

A new release of the ASTM CHETAH program for hazard evaluation: Versions for mainframe and personal computer

CHETAH, which stands for the Chemical Thermodynamic and Energy Release Program, was introduced in 1974. Since then, the CHETAH program has been widely used in the chemical industry for hazard evaluation. Although its chief aim is to predict deflagration/detonation potential from molecular structure, it can also be used to estimate heats of reaction, heat capacities, and entropies. One of the limitations of the original program was its rigid, punched card oriented format for data input and the lack of an overall hazard rating derived from the several hazard criteria. A new release of this program alleviates these shortcomings and includes other improvements. The main features of the new release are: 1) a totally interactive front end, 2) an interpreter subroutine which uses sophisticated pattern recognition techniques to combine the four hazard criteria into an overall hazard rating, 3) recognition of certain atomic groupings which are known to be sensitive, 4) correct handling of the symmetry number, and 5) an updated data bank. One of the most important features of this release is its availability in an IBM PC compatible version, making the program accessible to more users.     

浅谈水利水电工程设计防火安全标准

在开展国家科技基础条件平台项目“水工程安全标准研究”中,结合《水利水电工程设计防火规范》（SDJ 278-90）的修订工作,分析并介绍了水利工程设计防火安全条款的主要内容.     

宝日希勒露天煤矿边坡大面积火区灭火方法

随着露天矿开采规模的扩大,露天矿边坡暴露面积增大,边坡煤经过自然氧化自燃发火严重,尤其是在呼伦贝尔市春季风大(平均风力3-5级)刮风时间长(40天左右),自然发火威胁着采场安全,宝日希勒露天矿通过采取三个阶段得以解决.     

CNG加气站固定储气设施的防火间距研究

CNG加气站的安全间距与城市安全及土地利用密切相关,为在满足安全要求的前提下降低安全间距,提高土地利用率,对CNG加气站的防火间距进行了研究。基于Chamberlain模型,对CNG加气站内固定储气设施发生燃气泄漏燃烧的热辐射进行数值分析,结合地下抗爆泄压式新型固定储气设施的研究成果,利用Matlab对不同形式的固定储气设施发生燃气泄漏燃烧事故时的热辐射情况做出相应的数值计算。计算结果表明,新型的固定储气设施(技术)可以有效地缩小其防火间距,提高CNG加气站的土地利用率。     

Documentation and utilization of the results of hazard evaluation studies

A Hazard Evaluation (HE) study is not finished until the study documentation is complete and all of the issues and recommendations from the HE study have been resolved. While the extent and detail of the HE documentation will vary depending on the HE technique used, and on the stage in the process life cycle at which the study is performed, all studies should include documentation in three categories:

• 1 Process documentation, defining the design and intended operation of the facility at the time the HE study was performed.
• 2 HE study documentation, recording the actual performance of the HE study and including, for example, meeting notes or worksheets, logic models, hazard index calculations, etc.
• 3 Action documentation, summarizing all recommendations, perhaps with prioritization, and listing actions taken in response to the recommendations.

Thorough and complete documentation of HE studies is essential for understanding the concerns which give rise to each recommendation, tracking action taken on recommendations to insure that all are resolved, using the HE study as a basis for subsequent HE or quantitative risk analysis studies, using the HE study to assist in the management of change, and periodic updating of the HE study. Modern computer based information storage and retrieval technology also opens the potential for use of HE study documentation as a tool for training and for process troubleshooting.