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51.
Routine sonography prior to genetic amniocentesis revealed the presence of a large complex mass with pulsating channels over the anterior fetal chest wall. This led to early termination of pregnancy in a fetus affected with the rare Klippel-Trenaunay-Weber Syndrome.  相似文献   
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53.
对外来入侵物种的现状、存在问题进行了说明,针对我省的实际情况从预防优于治理的思路出发,探讨了生物入侵预警机制的构建原则并论述了该机制的内容体系,提出了保障措施。  相似文献   
54.
环境风险预警方法与应急成套装备的应用展望   总被引:1,自引:0,他引:1  
介绍了环境风险预警方法建立的环境风险预警指标体系、环境风险源管理平台、环境风险源风险评估技术方法以及模块式应急成套装备的技术特点等;分析了环境风险预警方法与应急成套设备在危险化学品环境风险与应急管理,在区域大气环境挥发性有机污染物(VOCs)监控预警等方面的实际需求。面临现实的环境风险状况从环境风险防控与应急工程技术研究中心建设角度提出了需进一步完善、开发的环境风险预测预警技术与应急成套装备等新思路。  相似文献   
55.
为推进农村环境综合整治工作,针对环办[2010]136号规定评估指标体系应用过程中遇到的问题,采取定义与计算、定性与定量结合的方法,对规定评估指标进行定义、明确赋分依据,确定不同完成程度下的赋分标准和计算方法,为环境成效评估提供科学、准确、可行、实用的赋分依据和办法。  相似文献   
56.
昭通地区滑坡泥石流预警系统及其减灾效益分析   总被引:6,自引:1,他引:5  
李观德 《灾害学》1998,13(1):50-52
阐述了昭通地区滑坡泥石流预警系统的由来与建立。该系统5a成功预报了11起滑坡泥石流灾害,419人幸免于难,预报成功率达58%。表明了在滑坡泥石流点多面广、灾情严重的地区建立预警系统是一条费省效宏的有效路子。  相似文献   
57.
洪水的等级划分及其减灾意义   总被引:11,自引:3,他引:11  
根据地震,风力等级的数学结构,提出一种洪水等级划分公式;对用等级表示洪水大小的减灾意义作了初步分析。  相似文献   
58.
In 1991, provisions for environmental impact assessment in New Zealand were changed significantly with the enactment of the Resource Management Act. Among other provisions, this act requires consideration of cumulative impacts in environmental assessment activities undertaken by planners in newly created regional authorities and district and city councils. The institutional context in which the act is being implemented offers both opportunities and constraints to cumulative impact assessment. A lack of methods for CIA is a recognized problem. However, methods that have been developed for environmental impact assessments can be modified to incorporate second-, third-, and fourth-order impacts as well as to identify the direction and magnitude of additive and synergistic impacts. Layered matrices and combined networks are examples of such methods. While they do not allow for scientific prediction, they do provide the practitioner with the ability to consider the cumulative impacts of decisions. This is crucial in New Zealand, where statutory requirements are ahead of established methodologies.  相似文献   
59.
A new method called SREST-layer-assessment method with automated software tool is presented that in a hierarchical approach reveals the degree of non-ideality of chemical processes with regard to SHE (safety, health and environment) aspects at different layers: the properties of the chemical substances involved (substance assessment layer (SAL)), possible interactions between the substances (reactivity assessment layer (RAL)), possible hazard scenarios resulting from the combination of substances and operating conditions in the various equipments involved (equipment assessment layer (EAL)), and the safety technologies that are required to run a process safely and in accordance with legal regulations (safety-technology assessment layer (STAL)). In RAL, EAL and STAL the main focus is put on process safety. A case study is used to show the principles of the method. It is demonstrated how the method can be used as a systematic tool to support chemical engineers and chemists in evaluating chemical process safety in early process development stages.  相似文献   
60.
In this paper, compared with a UN cylindrical 500 mL Dewar (H.4 in the UN tests), a spherical 1 L Dewar vessel was used to study the early stages of runaway reactions of several liquid and solid samples, including three organic peroxides and a reactive material. The samples were filled in the vessels and the temperature profiles versus times at different positions of the samples were measured. As a result, the minimum temperatures, defined as the SADT, were averagely 10 K lower than those measured in the cylindrical Dewar vessels. At the same time, the temperature profiles of solids in the spherical Dewars tended to be homogeneous. The heat transfer coefficient of a spherical Dewar is only 0.18 W/K/m, one-eighth of a conventional cylindrical Dewar vessel. Meanwhile it has a low phi factor. These factors are essential to simulate low heat loss bulk conditions in the equilibrium process and at the early stage of a runaway reaction. To characterize the ability of the adiabaticity of a storage vessel, it can be seen that a spherical Dewar could simulate the plant process having critical storage size of a reactive-material, r0, approximately 0.6 m. It is recommended that such a technique is used to investigate the SADT of an unstable material in larger scale packaging or a material with very weak heat release in industry.  相似文献   
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