锂的用途及其资源开发

锂在原子能工业中具有十分独特的地位 ,被誉为“高能金属” ;它推动着能源工业 ,尤其是电池技术的发展 ,无愧于“能源金属”和“推动世界前进的金属”的称谓。随着技术的发展 ,世界锂业的传统格局和市场分布发生了较大的变革 ,盐湖提锂技术的进步打破了半个世纪以来锂资源的分布和供应格局 ,而澳大利亚、俄罗斯、加拿大和津巴布韦等硬岩型锂资源大国将失去其在世界锂资源和锂盐供应市场上的优势。智利、中国、阿根廷和玻利维亚等国将成为世界拥有锂资源大国。盐湖工业生产的锂产品适应于当今知识经济时代的需求 ,市场前景广阔。笔者介绍了金属锂的一些重要用途 ;分析了锂资源开发的现状 ;指出我国盐湖卤水提锂技术已取得了重大突破 ;透露了作为国家计委批准的西部高技术产业化示范工程项目有关信息 ,年产 30 0 0吨碳酸锂生产线 ,将于2 0 0 5年 6月正式投产。     

自然通风消除热源厂房热害的数值模拟与实践

在有余热余湿的厂房 ,大多采用自然通风。笔者采用k ε紊流模型 ,对某钢铁公司二高线厂房自然通风消除热害进行了数值模拟。将生产线上的散热量作为能量方程的附加源项 ,计算厂房内的速度场和温度场 ,优选出了该热源厂房的通风改造方案 :进风口的标高降低 2m ,在操作平台上设置开孔率为 30 %的通风栅栏板。通过对通风改造前、后厂房内温度实测值的对比 ,厂房工作区平均温度下降 5℃ ,风速由原来的平均 0 .2m/s增加到 1.6m/s,厂房内作业区的热环境有明显改善 ,防止了因热环境问题造成的安全事故 ,提高了工人的生产效率。     

基于资源安全的企业人才风险管理

从资源安全的角度出发 ,笔者阐述了企业人才资源的重要性 ;对我国企业目前面临的主要人才风险进行了识别 ;指出我国企业目前的人才风险主要来自人才外流、人才获取、人才道德和人才风险意识四个方面 ;强调了我国企业加强人才风险管理的重要意义。从人才风险引起的各项损失及其损失概率的角度 ,提出了企业进行人才风险估测的方法 ;建立了人才风险损失模型 ;指出了我国企业的人才风险管理、有效防范人才风险的途径。     

Perceived values of benefits from Mississippi's forestry Best Management Practices

Numerous studies in the United States have shown that, in addition to accomplishing their primary objective of preventing or reducing non-point source (NPS) pollution, silvicultural Best Management Practices (BMPs) provide additional direct and indirect benefits. These benefits are valuable to a host of forestry-related groups because they improve forest habitat, improve the public's perception of the timber industry, and increase the overall value of the timber asset. In an effort to gauge the perceived value that forestry-related groups place on BMPs, Mississippi non-industrial private forest (NIPF) landowners (n=63), forestry consultants (n=30), and timber industry professionals (n=8) were surveyed using a combination of in-person, telephone interviews, and mail surveys in spring 2001. Each group was asked to rank 35 potential benefits from 1 to 5 (1 being least beneficial; 5 being most beneficial) according to their perceived value of the benefit. Results showed little variation in the overall mean response for all benefits among groups. In general, all groups assigned a ranking of average, more beneficial, or most beneficial to 31 of 35 (88%) potential benefits. Results indicated that, although these groups may have differing perceptions of the value of some benefits, all have a largely positive perception of the potential benefits from BMPs.     

Irrigation water management policies: Allocation and pricing principles and implementation experience

Food security and sustainable development require efficient use of water resources, especially in irrigation. Economic pricing can be an effective tool to achieve more efficient water use, provided it is supported by other policies in implementation. Applying various water pricing and cost recovery arrangements is suggested for efficient allocation. Any adverse impact on farmers’ incomes must be addressed and more reliable service must accompany higher prices. Experience from several countries suggests a variety of implementation issues. Essential complements to water pricing are water distribution rules and technological choices at critical nodes in the delivery system that allow farmers flexibility in conserving water in response to higher prices. Among supporting institutions, water users associations seem a higher priority than water markets.     

Influence of ethnicity on recreation and natural environment use patterns: Managing recreation sites for ethnic and racial diversity

Management of natural environment sites is becoming increasingly complex because of the influx of urbanized society into wildland areas. This worldwide phenomenon impacts a wide range of countries. In southern California ethnicity is often a major factor influencing recreation site use and behavior at sites in the wildland-urban interface. This study investigated the role of ethnicity and race on the use patterns, perception of environment, and recreation behaviors at an outdoor recreation site visited by an ethnically diverse population. Two research questions were asked: (1) What ethnic groups engage in outdoor recreation at this site, and (2) what differences can be assigned to these various groups? Data were collected from 250 recreationists during 1991. Three major ethnic groups were identified, and statistically significant differences were found in the importance of site attributes, activity participation, and in preferred and actual communication channels. Management implications and strategies based on group differences are discussed.     

The role of analytical science in natural resource decision making

There is a continuing debate about the proper role of analytical (positivist) science in natural resource decision making. Two diametrically opposed views are evident, arguing for and against a more extended role for scientific information. The debate takes on a different complexion if one recognizes that certain kinds of problem, referred to here as “wicked” or “trans-science” problems, may not be amenable to the analytical process. Indeed, the mistaken application of analytical methods to trans-science problems may not only be a waste of time and money but also serve to hinder policy development. Since many environmental issues are trans-science in nature, then it follows that alternatives to analytical science need to be developed. In this article, the issues involved in the debate are clarified by examining the impact of the use of analytical methods in a particular case, the spruce budworm controversy in New Brunswick. The article ends with some suggestions about a “holistic” approach to the problem.     

Establishing management standards: Selected examples of the normative approach

The importance of developing evaluative standards for judging the acceptability of impacts caused by recreation is common to all recent natural resource management frameworks. A normative model has been advanced as a useful way to conceptualize, collect, and organize empirical data representing standards for resource management issues. This article summarizes the findings from social and ecological research to illustrate the utility of the normative approach from a manager's perspective. The social data (e.g., encounter norms, proximity norms, and tolerances for launch wait times) were obtained from 13 different study sites, while the ecological data (e.g., tolerances for the amount of bare ground, size of fire rings, instream flows, and wildlife management practices) were collected at three specific sites and from one statewide survey, Findings from the social research indicated that encounter norms exist for particular types of contacts with certain types of visitors at particular places and for certain types of experiences. The recreationists reported norms for acceptable distances between individuals, encounters with others at campsites or attractions, and waiting times to run rapids. These social norm evaluation techniques were also shown to be transferable to normative evaluations of ecological impacts. The users had opinions about ecological impacts and were willing to express them. In addition, the ecological norms were of moderate to high intensity. It is argued that the usefulness of normative approaches lies in their ability to characterize group agreement about appropriate use conditions or impact levels for a particular recreation experience, thus providing the evaluative information needed to establish management standards.     

陕西省自然灾害的减灾对策

陕西地质地理条件复杂,自然灾害频繁而严重。本文概括分析了省内自然灾害的主要类型和分布特点,简要回顾了近几十年减灾工作的成绩,在此基础上着重讨论了今后减灾工作的对策和减灾目标。     

Birth of a megaproject: Political economy of flood control in bangladesh

A major flood control initiative has been launched in Bangladesh under the coordination of the World Bank. The bank's five-year Action Plan is intended to initiate a long-term investment program, the specifics of which remain to be determined. Long-term proposals under consideration include the construction of massive embankments along the great rivers of the Bangladesh delta. The wisdom of such a “structural solution” to Bangladesh's flood problems can be questioned on economic, environmental, and technical grounds. Regrettably, the decision-making process has not encouraged wide debate on these questions.