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231.
渤海辽东湾附近海域在严寒季节海冰分布广泛,核电厂向受纳海域排放的温排水带有大量乏热,将导致海域内水温升高而引起海冰融化。某核电厂址西侧海域有一斑海豹国家自然保护区,电厂温排水及其融冰效应可能影响斑海豹的生存、繁殖环境。文章根据核电厂温排水融冰模型对其融冰量的预测和环境影响分析,表明了电厂温排水对斑海豹保护区的影响是在较小范围内的。  相似文献   
232.
高职环保类专业职业技能培养课程体系开发   总被引:1,自引:0,他引:1  
课程体系是高职专业办出特色、持续发展的载体。针对高职环保类专业人才培养存在课程体系不合理、实践教学薄弱、职业技能培养方法陈旧等问题,以职业岗位需求为基础,以职业技能培养为主线,构建了以实际污染治理项目为载体的高职环保类专业职业课程体系和职业核心课程。通过职业核心课程建设、双师型师资队伍建设、校内外实训基地建设等措施实现职业技能的培养。  相似文献   
233.
Abstract

In the last few years, marked progress has been made in the development of methods for evaluating the mutagenic and carcinogenic potential of pesticide chemicals. The correlation of genetic and related biological activity in short‐term tests with carcinogenic activity in whole animals allows the utilization of short‐term mutagenicity bioassays to prescreen chemicals for effects related to mutation induction and presumptive carcinogenicity. In addition, bioassays now available can measure directly the chemical transformation of normal cells in culture into cells capable of producing tumors when injected into animals.

This paper will review briefly the major types of relevant short‐term tests and will develop a rationale for a phased approach to the evaluation of the mutagenic and carcinogenic potential of environmental chemicals. This approach involves the sequential application of bioassays which are organized into a three‐level matrix emphasizing first detection, then confirmation, and finally hazard assessment. Chemicals demonstrating positive results in the short‐term detection systems and confirmatory bioassays are pursued in higher level whole animal tests. A core battery of tests is proposed to operationally define a negative result. The phased approach should facilitate a cost effective utilization of limited testing resources and provide protection for human health in proportion to the anticipated hazard.

Results obtained in evaluating a series of thirty‐eight pesticide chemicals according to the phased approach are discussed in detail.  相似文献   
234.
Research core and framework of sustainability science   总被引:8,自引:6,他引:2  
This paper reviews recent achievements in sustainability science and discusses the research core and framework of sustainability science. We analyze and organize papers published in three selected core journals of sustainability science: Sustainability Science, Proceedings of the National Academy of Sciences of the United States of America, and Sustainability: Science, Practice, & Policy. Papers are organized into three categories: sustainability and its definition, domain-oriented research, and a research framework for sustainability science. First, we provide a short history and define the basic characteristics of sustainability; then we review current efforts in the following research domains: climate, biodiversity, agriculture, fishery, forestry, energy and resources, water, economic development, health, and lifestyle. Finally, we propose a research framework for sustainability science that includes the following components: goal setting, indicator setting, indicator measurement, causal chain analysis, forecasting, backcasting, and problem–solution chain analysis. We emphasize the importance of this last component for improving situations and attaining goals.  相似文献   
235.
温度、SO_2浓度、颗粒大小、石灰石类型和样品的微观结构影响着直接硫酸化反应过程。这一反应过程能用缩芯模型来描述,并对SO_2具有一级反应特征。本征反应和产物层扩散控制反应的活化能分别是85.2kJ/mol和41.5kJ/mol。在800℃、2000ppmSO_2和反应101min的条件下,Igzlaberga和Forsby石灰石的CaCO_3转化率分别可达84%和72%。在初始2min内已煅烧石灰石(CaO)的硫酸化反应速率与石灰石的反应速率稍高,随后二者基本相同。  相似文献   
236.
为探究融冰过程中重金属离子的迁移规律,选择铁离子和锰离子为研究对象,开展了室内模拟融冰实验,探讨其在融冰过程中的迁移规律,并分析初始浓度和冷冻温度对其迁移过程的影响.结果表明:在不同的初始浓度和冷冻温度条件下,铁离子和锰离子在冰中各层的浓度分布关系皆为:中层 < 上层 < 下层;融冰过程中,51.17%~71.67%的铁离子和锰离子均在冰体融化前期(0~25%)集中释放,中后期相对平稳均匀释放,此外初始浓度对冰融化时铁离子和锰离子的迁移规律影响不大,而冷冻温度较低时,融1中铁离子和锰离子的浓度基本在增加;融冰过程中,随着累积融水体积的增加,融水中铁离子和锰离子的浓度与冰体初始浓度之比逐渐降低,它们之间呈指数函数衰减模式.  相似文献   
237.
Abstract

This methodological paper draws on research from Australia to examine the question of gaining access to local governments in undertaking work on natural resource management. It is argued that a range of macro-level changes have impacted on the local government sector in Australia, and these changes have rendered access problematic for researchers. These changes include an expansion of local government roles, an increase in financial pressure within the sector, a proliferation of audit measures across local governments and a low level of respect amongst local government personnel for academics and academic work. The paper concludes by identifying the reasons why understanding access in qualitative research on local government and environmental sustainability is important.  相似文献   
238.
职业是经济社会分层的表征,职业指导随着经济社会和职业的发展应运而生。从就业形势、社会对高校人才培养的要求及大学毕业生职业核心竞争力缺失等方面对高校就业工作现状进行了分析,提出将职业指导融入人才培养机制、目标、方法和内容等各个层面,实现大学生有序就业,完成高校办学与社会需求之间的有效对接。  相似文献   
239.
This paper examines the role of proactive personality in the receipt of informal mentoring received (i.e., psychosocial and career‐related mentoring) among a sample of 174 early career employees in China. The regression results indicated that networking behavior mediated the relationship between proactive personality and career‐related mentoring, whereas voice behavior mediated the relationship between proactive personality and psychosocial mentoring. Furthermore, core self‐evaluations moderated the aforementioned two indirect relationships such that they were stronger at higher levels of core self‐evaluations. Our analyses also showed that the moderating effects occurred at the first stage of the indirect relationships. We discuss the theoretical and practical implications of these findings. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
240.
河冰对桥墩作用的冰荷载计算方法(Ⅱ)——冰压力计算公式   总被引:10,自引:0,他引:10  
在松花江河冰力学性能试验和流冰动压力测量的基础上,回顾了国内外目前有关冰-结构相互作用与冰荷载计算的主要方法和公式,并通过黑龙江省流冰长期观测数据的统计分析,提出了适合我国国情的冰荷载计算方法,可供工程部门参考使用。  相似文献   
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