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排序方式: 共有1291条查询结果,搜索用时 15 毫秒
101.
DZH2-8型蒸汽锅炉事故原因及预防措施   总被引:1,自引:0,他引:1  
企业轻投入重产出,是发生事故的根本原因,水处理措施不完善,是造成事故的直接原因,管理人员、操作人员素质低是导致事故率高的不可忽视的因素。  相似文献   
102.
在再生资源产业快速发展过程中,集散市场、分拣中心与加工园区等新兴产业形态令人瞩目。这些新兴产业形态的出现是再生资源产业经济效率提高的要求,是产业地位提升的需要,是先进理念注入的结果,是技术进步的必然趋势。其代表着再生资源产业更先进的生产力,标志着再生资源产业的庞大产业链条正在形成。应从新兴产业形态中,发掘再生资源产业发展的内生动力,推动再生资源产业又好又快发展。  相似文献   
103.
Actually, embryos can be cultured from the one‐cell stage up to the blastocyst stage, and their development can be easily monitored at any time: severe effects caused by toxic compounds are traduced by rapid embryonic death, less pronounced effects can be expressed by a lowered cleavage activity or by an arrest of the development from a particular stage. The system can be improved by transferring the embryos at the blastocyst stage in another more complete medium where they can “implant”; and form an inner cell mass with differentiated ectoderm and endoderm. Since last years, it has also become possible to culture postimplantation rodent embryos for short periods involving a number of particularly critical stages of organogenesis, such as the formation and closure of the anterior neuropore. Embryo‐culture also represents a useful system to study cytogenetic effects of chemicals which are often linked to lethal or teratogenic effects. These different possibilities are illustrated by examples of studies already performed with metals, and dealing with their teratogenic and/or cytogenetic effects on pre‐ and postimplantation rodents.  相似文献   
104.
Bacterial systems have not had success predicting metal carcinogenicity. Hypotheses explaining this failure are examined. Using a broad genetic endpoint, λ prophage induction, under sub‐toxic growing conditions, genotoxicity is seen for compounds of chromium, manganese, lead, molybdenum and tungsten. Copper, manganese, arsenic and molybdenum compounds enhanced UV mutagenesis in E. coli WP2.

The toxicity of metal compounds to cultured mammalian cells correlates well with rat oral LD50 values. Whereas insolubility can present problems in bacterial studies, concentrations of metal compounds toxic to mammalian cells can be determined even in the presence of precipitate, and sometimes [Pb(NO3)2, BaCl2 and BeCl2] occurs only in its presence. PbS and MnS, which are insoluble, are much more toxic than the more soluble compounds Pb(NO3)2 and MnCl2. These results demonstrate the importance of cellular phagocytosis of insoluble metal compounds as a factor in studying the toxicity and genotoxicity of metal compounds.  相似文献   
105.
Kyoo‐Man Ha 《Disasters》2018,42(4):804-822
Numerous Western researchers have examined the influence of Confucianism on development in Asia, but almost no South Korean researchers have studied the topic in regard to emergency management in their own country. This study begins by considering Confucianism as a social culture. Next, it goes on to evaluate its role in South Korea's emergency management system, contributing, ultimately, to efficiencies in emergency management. Drawing on a literature review and a case study, the paper assesses the double‐ and single‐faced approaches, using four major Confucian components: destiny; family; ritual; and relation. The double‐faced approach includes the positive and negative aspects of emergency management, whereas the single‐faced approach incorporates only its positive aspects. This paper provides, for the first time, a systematic analysis of the relationship between Confucianism and emergency management in South Korea. Its key finding is that the double‐faced approach needs to be transformed into a single‐faced approach through active facilitation of behavioural change.  相似文献   
106.
为了改善L大学安全状况,提高L大学安全文化建设水平,采用文献对比分析法研究高校安全文化定义及其理论实质,从狭义的角度提出高校安全文化是高校管理的一系列安全理念,具体化为32条高校安全文化核心元素。以L大学为研究样本,定性分析其安全文化建设内容;编制高校安全文化定量测量量表,对其安全文化建设水平进行定量测量。评价结果表明L大学安全文化建设存在缺欠,提出了实用性对策措施和建议。  相似文献   
107.
实物型水资源资产负债表表式结构设计   总被引:7,自引:1,他引:6  
秦长海  甘泓  汪林  贾玲  游进军  周普 《自然资源学报》2017,32(11):1819-1831
论文在阐述资产负债表基本概念和原理的基础上,遵循会计恒等式、复式记账规则和权责发生制的记账基础,结合我国水资源管理的实际,提出了基于会计学的水权益实体水资源资产负债表表式结构和基于统计学、经济学的国家(地区)水资源资产负债表表式结构,从而实现能够反映水权益实体之间和经济体与环境之间关于水资源资产的债务债权关系的水资源资产核算,实现国家和行政区层面的水资源资产负债核算,为生态文明体系建设、自然资源资产核算、领导干部离任审计考核等提供必要的基础信息,也为进一步完善水资源资产负债表账户体系奠定基础。  相似文献   
108.
三峡库区淹没区土壤重金属形态分布及其对水质影响   总被引:11,自引:3,他引:8  
结合三峡水库调度模式,在汛期及汛后对库区淹没区土壤中重金属Cu,Pb,Cd,Cr的存在形态、迁移转化特征及其对水体水质的影响进行研究.结果表明:不同重金属在库区土壤中存在形态不同,Cu和Cr主要以残渣态存在,w(残渣态Cu)和w(残渣态Cr)平均值为87.41%和96.04%,而w(可提取态Pb)和w(可提取态Cd)较高,平均值为41.95%和88.14%,生态风险相对高于Cu和Cr.在汛期三峡水库低水位运行,水体重金属含量较高,汛期水体ρ(Pb)和ρ(Cd)分布特征与土壤w(Pb)和w(Cd)分布呈显著相关性,而汛后水库首次172 m高水位蓄水,由于水环境因素的改变,水体中重金属含量显著降低,汛后淹没土壤重金属形态含量变化细微,土壤淹没对库区水体水质影响小,不构成汛期、汛后水体重金属含量波动的主因.   相似文献   
109.
This article focuses on employee direct participation in occupational health and safety (OHS) management. The article explains what determines employee opportunities to participate in OHS management. The explanatory framework focuses on safety culture and safety management at workplaces. The framework is empirically tested using Estonian cross-sectional, multilevel data of organizations and their employees. The analysis indicates that differences in employee participation in OHS management in the Estonian case could be explained by differences in OHS management practices rather than differences in safety culture. This indicates that throughout the institutional change and shift to the European model of employment relations system, change in management practices has preceded changes in safety culture which according to theoretical argument is supposed to follow culture change.  相似文献   
110.
Abstract

This study compares energy use for food transport to a farmers' market in Sweden with energy use for transport in the conventional food system. The farmers' market was investigated through data sampling from on-site investigations. The conventional food system was studied with the aid of life cycle assessments reported in the literature. Overall, the study found no significant differences in levels of energy use for transport to the farmers' market compared with the conventional food system. For certain products, such as fresh fruits and vegetables, transport-related energy use was much lower in the local system although the season in Sweden for this kind of product is restricted to two or three months at the end of the summer. However, there is considerable potential to increase energy efficiency in local food systems by organizing the selling in new ways and by using more energy efficient vehicles.  相似文献   
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