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151.
为研究在居民区附近开展大面积爆破施工的安全可行性以及安全控制距离标准,采用数值模拟方法,分析了地铁车辆段爆破施工对周边高压线及居民楼的影响,根据分析结果,给出了安全控制距离及关键控制指标,说明采用数值模拟的方法适用于类似工况的可行性。另外,研究发现,在居民楼附近进行地铁车辆段爆破施工风险较高,建议在距建构筑物100 m范围内采用静态爆破或机械开挖的方式进行施工。  相似文献   
152.
建筑企业安全文化对安全绩效影响的实证研究   总被引:1,自引:0,他引:1  
基于安全文化在建筑业安全管理中的重要性越来越突出,因此安全文化对于提高安全绩效,减少建筑业事故发生率的作用日益得到重视。文中进行实证研究,探讨建筑企业安全文化对安全绩效的影响。安全文化的维度为安全制度文化、安全物质文化和安全观念文化,研究结果表明,安全制度文化、安全物质文化和安全观念文化均有助于安全绩效提高,研究结果可在一定程度上促使建筑企业重视并自觉改善安全文化,有助于减少建筑业安全事故发生率,提升安全绩效。  相似文献   
153.
在设计阶段对压力容器出具风险评估报告会增加设计难度,也对设计人员有了更高的要求。针对如何具体实施风险评估,本文提出了煤化工行业变换炉的风险评估的技术,以便与同行交流,旨在推广风险评估技术,促进风险评估技术的应用推广。  相似文献   
154.
分析了桑树的生态作用,根据山西省不同立地条件,提出了水土保持桑树生态林和绿化观赏桑树生态林两种主要栽植模式.  相似文献   
155.
In this study, we used a within‐person daily research paradigm to examine the relationship between daily family–work conflict (FWC) and daily job performance. On the basis of theory on dynamic behavior, we hypothesized that concentration serves as a mechanism through which daily FWC impairs daily job performance. We further predicted that psychological detachment from work during time‐off (i.e., mentally switching off) buffers the negative relationship between daily FWC and daily job performance. Ninety‐five employees completed daily surveys over one workweek. Multilevel modeling results showed that daily FWC was negatively associated with daily job performance and that concentration mediated this relationship. Furthermore, general psychological detachment, but not daily psychological detachment, buffered the negative relationship between daily FWC and daily job performance. The current findings suggest that daily FWC has negative performance implications and that the general level rather than the daily level of psychological detachment from work helps alleviate the negative implications. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
156.
In order to develop better process hazard analysis (PHA) approaches, weaknesses in current approaches first must be identified and understood. Criteria can then be developed that new and improved approaches must meet. Current PHA methods share common weaknesses such as their inability specifically to address multiple failures, their identification of worst-consequence rather than worst-risk scenarios, and their focus on individual parts of a process. There has been no comprehensive analysis of these systemic weaknesses in the literature. Weaknesses are identified and described in this paper to assist in the development of improved approaches. Knowledge of the weaknesses also allows PHA teams to compensate for them to the extent possible when performing studies.Key criteria to guide the development of improved methods are proposed and discussed. These criteria include a structure that facilitates meaningful brainstorming of scenarios, ease of understanding and application of the method by participants, ability to identify scenarios efficiently, completeness of scenario identification, exclusion of extraneous scenarios, ease of updating and revalidating studies, and ease of meeting regulatory requirements. Some proposals are made for moving forward with the development of improved methods including the semi-automation of studies and improvements in the training of team members.  相似文献   
157.
渤海海峡跨海通道建设环境影响研究   总被引:3,自引:0,他引:3  
渤海海峡跨海通道建设是一项高技术、高投入的特大战略性工程,工程建设具有重大的经济、军事和政治意义,但是也必将对环境产生重大影响。本文在对各界专家一致推荐的“伏贴式隧道和隧道桥”方案进行简要分析的基础上.论述了对工程建设进行环境影响研究的必要性,提出了环境影响评价工作程序与工程决策生命周期的耦合过程,以便从工程源头控制环境影响的产生;初步探讨了工程施工期和运营期的环境影响识别内容,结果表明:采用“伏贴式隧道和隧道桥”方案,相对于其它方案对资源、生态环境的干扰和影响是最小的;并提出了预防和减缓不良环境影响的对策措施,为工程的环保施工与运营提供科学依据。  相似文献   
158.
In recent years, the exposure of humans to phthalate esters through environmental contamination has increased. One among them is di-ethyl phthalate (DEP), which is used as a plastisizer for cellulose ester plastic films and sheets, solid rocket propellants, molded and extruded articles, as a component in insecticide sprays and various other substances, as well as in industrial applications. Release into the environment occurs primarily as a result of production and manufacturing of DEP and during the use and disposal of products containing DEP. Therefore, a study was undertaken to evaluate gender-specific toxicity of DEP in Wistar rats. Rats of both sexes, weighing 125–130?g, were administered 50?ppm (w/v) DEP in water ad libitum for a period of 180 days and were given normal diet. Control animals received normal diet and water ad libitum. During the treatment, rats were weighed every week and water consumption per day was measured. After the completion of treatment, liver weight?:?body weight?1 ratio, liver weight, body weight?1, liver and serum enzymes, and other biochemical parameters of liver and serum were assessed. It was observed that there was no significant change in body weight?1, liver weight, liver weight?: body weight?1 ratio, and water consumption in both sexes. There were significant increases in liver acid phosphatase (ACP) activity and kidney glutathione levels, and nonsignificant changes in liver alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), succinate dehydrogenase (SDH), and lactate dehydrogenase (LDH) activities in DEP-treated male rats, whereas in DEP-treated female rats the liver showed significant decrease in ALP and SDH and nonsignificant changes in AST, ALT, and LDH activities. Serum ACP and LDH levels in DEP-treated male rats were significantly decreased, and in the case of DEP-treated female rats, only serum LDH levels were significantly decreased. There was no significant change in serum ALP, AST, and SDH levels in DEP-treated male and female rats as compared to control rats. Histology of the livers of both male and female rats showed loss of hepatic architecture, degenerative changes in hepatocytes, and vacuolation in hepatocytes in both the centrilobular and periportal areas. It can be concluded from this study that prolonged exposure to DEP at 50?ppm levels can be harmful to animals and humans. This is evident from the present study as certain significant changes in enzyme activities in the liver, serum, and histological alterations in liver were observed.  相似文献   
159.
Degradation of Acid Red I (ARI) dye by electrochemical treatment and UV light irradiation was studied in this work. The effect of the current density and the concentration of NaCl and dye on the decoloration and degradation efficiency were studied and optimized. The UV irradiation was monitored by UV-Vis spectrophotometry and chemical oxygen demand. The kinetic constants for decoloration and degradation were calculated. Degradation of 86% was achieved in 160?min and the first-order kinetic constant was 0.013?min?1. Degradation products were identified by gas chromatography/mass spectrometry. The mechanism for the degradation of ARI was proposed.  相似文献   
160.
根据全球沙尘气溶胶气候模式GEM-AQ/EC模拟的1995~2004年的沙尘起沙量和干湿沉降量,分析了沙尘气溶胶源汇的全球时空变化特征.全球沙尘起沙量集中在各个主要沙漠地区,北非对全球沙尘气溶胶贡献最大为66.6%.沙尘气溶胶沉降的高值区分布在沙漠源区及其紧临的下风地区.最大净沙尘气溶胶接收主要分布在沙漠周围地区并形成净接收量大于10t/(km2×a)的位于0°N~60°N之间的北非、欧亚大陆、西太平洋、北印度洋、北美和大西洋的带状分布.在北非、阿拉伯半岛、中亚、东亚和澳大利亚5个主要沙漠地区中,起沙量和沉降量都存在明显的季节变化,除中亚其他4个区域干湿沉降量和起沙的季节变化基本一致;东亚地区沙尘气溶胶起沙量和总沉降量的季节变化最为明显,而北非沙漠起沙量和总沉降量的季节变化最小,其他3个区域的季节变化幅度基本相同.中亚起沙峰值和阿拉伯半岛起沙次峰值出现在夏季,其他区域的峰值均出现在春季.10年间全球陆地年平均起沙量为(1500±94)Mt,保持略微上升趋势.以北非沙漠起沙量年际变化率最低(6.3%), 而以东亚(28.3%)和澳大利亚(45.0%)起沙量年际变化最为明显;全球陆地的沙尘气溶胶沉降量以约9.9Mt/a的速率递减,全球海洋的沙尘气溶胶沉降递增.  相似文献   
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