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71.
Despite recent major chemical process accidents in Japan, the top management teams of firms still avoid taking costly risk reduction measures because of their low perceived impact on firm performance. The disclosure of information on accident risks might motivate managers to enhance workplace safety because of the subsequent evaluation of firms by investors in stock markets. If the disclosed risk information is newly available for investors, firms with a high risk of accidents would receive a poor evaluation by stock markets and thus managers would take risk reduction measures to prevent stock prices from declining. In this study, we conduct an event study analysis to examine whether accident risk information is already reflected in stock prices, using data on the Japanese chemical industry. The results of our event study show that the estimated cumulative average abnormal returns of firms' stocks are significantly negative after severe accidents actually occurred. This finding implies that risk information is not already reflected in the stock prices of Japanese chemical firms and that the disclosure of accident risk information has the potential to motivate the top management teams of firms to reduce their firms’ accident risk.  相似文献   
72.
职业安全绩效指标研究   总被引:1,自引:2,他引:1  
为了建立企业安全生产长效机制,提高安全管理水平,预防事故的发生,笔者在研究国内外企业安全绩效要素及分类方法的基础上,提出了包含10个一级要素及50个二级要素的企业安全绩效指标体系,并就指标的设立原则、定义、权重的确定和应用进行了阐述示例.同时,也为政府安全监管部门提供了科学决策的依据.  相似文献   
73.
Objective: Despite strong evidence of the effectiveness of child safety seats in reducing injuries, the use of these devices in some communities is still rare. The purpose of this study was to determine the prevalence of child safety seat use and the factors influencing its use in the safe community of Tehran.

Methods: This roadside observational study was conducted in 2015 and 2,178 personal cars with a child under 12 years aboard were observed on Tehran's streets in regard to use of child safety seats. Other variables such as the gender of the driver, driver's age group, type of street, region of municipality, time of day, and day of the week were also collected.

Results: Prevalence of child safety seat use was 4.3% and was significantly higher among women drivers, on freeways, and in municipal regions 1, 4, and 7.

Conclusions: The prevalence of child safety seat use in Tehran as a most populous member of the international safe community was very low and most children commuted in insecure situations in the vehicle. Therefore, it is proposed that plans should be made to increase the use of child safety seats in international safe communities.  相似文献   

74.
推导保护水生环境质量标准的方法研究   总被引:6,自引:0,他引:6  
综述了美国及欧洲一些国家推导水生环境质量标准的方法研究。对水生环境质量标准包括的水质标准,底泥标准,人类和野生生物标准进行了分别叙述,详细讨论了推导水生环境质量标准的数据要求和计算方法。  相似文献   
75.
The study aims to compare the detection of 16S rRNA gene of Dehalococcoides species and the microcosm study for biotransformation in predicting reductive dechlorination of chlorinated ethenes in ground water at hazardous waste sites. A total of 72 ground water samples were collected from 12 PCE or TCE contaminated sites in the United States. The samples were analyzed and used to construct microcosms in the laboratory. The results showed that the presence of Dehalococcoides DNA was well associated with dechlorination to ethene in the field. Nearly half of the wells where Dehalococcoides DNA was detected had ethene as a dechlorination end product. In comparison, for ground water samples of 16 wells where ethene was detected, ethene was produced in 11 of the corresponding microcosms. For most microcosms, during two years of incubation, dechlorination was less extensive than that observed in the field.  相似文献   
76.
基于SCP模型的节能环保市场分析研究   总被引:1,自引:0,他引:1  
从需求角度出发,区分了节能环保产业中三种不同类型的市场,然后以SCP模型为分析框架,对三种不同类型的市场结构、企业行为和绩效进行了分析和比较,归纳了节能环保产业中不同类型的市场所存在的问题和解决思路。  相似文献   
77.
对生物膜填料塔 液相生物处理的组合系统净化低浓度甲醛废气进行实验研究,结果表明,组合系统对甲醛废气的净化效果明显优于单独生物膜填料塔净化系统,甲醛净化效率提高35%以上,甲醛生化去除量增大50%以上.动力学研究结果表明,甲醛在生物膜上的生化降解反应为慢速生化反应,需要采取强化甲醛液相生化降解反应、提高反应速率的措施,来提高废气中甲醛的生物净化效果.  相似文献   
78.
A new analytical method using accelerated solvent extraction was developed for the determination of 10 particle-associated polar and semipolar pesticides. In addition, six deuterated analogues of the target compounds were evaluated as internal standards. The method yielded acceptable accuracy (73–103% recovery) and precision (<25% relative standard deviation) for eight compounds. Using size exclusion chromatography (SEC) as cleanup step resulted in higher recoveries compared to solid phase extraction (SPE) cleanup.

Deuterated standards with 10 or more deuterium atoms performed well as internal standards concerning similar recovery and correlation with the target analytes.

The method was employed to extract particle-associated pesticides from 16 streams located in an area with intense agriculture in France. Acetochlor, pirimicarb, tebuconazole, fenpropidin, -endosulfan and chlorfenvinphos were detected at concentrations up to 1 mg kg−1 dry weight. A comparison with aquatic toxicity data indicated potential risk to the benthic fauna exposed to these concentrations of pirimicarb, -endosulfan and chlorfenvinphos.

We suggest that the method presented here be used for the extraction and quantitation of particle-associated polar pesticides.  相似文献   

79.
    
《组织行为杂志》2017,38(7):1057-1075
Research to date has largely been unclear about whether a single perpetrator is sufficient to instigate the well‐documented negative consequences of workplace incivility. In the current research, we examine the extent to which perceived belongingness and embarrassment mediate the relationship between incivility from a single perpetrator and two important outcomes (job insecurity and somatic symptoms), and the extent to which the perpetrator's power moderates these relationships. Across two studies using different methods, we find that incidents of single perpetrator incivility are associated with target feelings of isolation and embarrassment, which in turn relate to targets' perceived job insecurity and somatic symptoms (Studies 1 and 2) both the same day and three days later (Study 2). Moreover, we find that perpetrator power moderates the relationship between incivility and embarrassment, such that targets are more embarrassed when the perpetrator is powerful. Implications for theory and practice are discussed. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
80.
采用改进直剪仪模拟桩与土之间的滑动摩擦,研究了沥青涂层对桩侧摩阻力的影响.试验结果表明,桩侧摩阻力与土的类型、法向应力有关,随着法向应力的增长,滑动摩阻力也相应增长,且增长近似呈线性关系;在一定的法向应力下,沥青涂层对减小滑动摩阻力有一定的作用,随着法向应力的增长,沥青涂层亦会导致滑动摩阻力增加.  相似文献   
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