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1.
祁妍娟  张千一  肖潇  王冰  卢志萍 《价值工程》2019,38(12):155-158
为研究路域土壤重金属的空间分布特征,以镇江市润州区龙门港路(透水沥青路面)与港前路(密实沥青路面)作为研究对象,探究土壤中重金属Pb、Zn的空间分布特征。通过分析路面径流雨水中Pb、Zn污染物含量,得出路面径流对土壤中重金属Pb、Zn含量的影响,并采集了80个土壤样品进行测试,利用单因子污染指数法、综合污染指数法进行了土壤重金属污染评价。结果表明:路面径流污染是导致土壤重金属含量较高的重要因素;城市道路重金属污染非常严重;透水沥青路面对重金属污染物具有一定的截留作用,减少了重金属进入土壤深处。  相似文献   

2.
张星  陈文德 《价值工程》2015,(12):212-213
通过对四川省巴中市土壤地球化学特征的研究,得到了六种典型元素Cd、I、Pb、S、Se、Zn在各县域的含量。研究结果为:巴中市土壤元素比较指数为0,土壤质量与全国水平相当。六个典型元素中除Cd元素以外,其他元素均未超出中国土壤环境质量一级标准,均符合中国土壤环境质量二级标准。尼梅罗综合指数评价表明,各县域土壤污染指数均小于0.7,巴中市土壤清洁。  相似文献   

3.
在工业生产的过程中,由于重金属污染物的排放,使得工业生产用地受到不同程度的污染。同时生态圈是一个有机的统一整体,如果重金属污染物进入工业用地中,那么与其相关联的地表水及农业用地也会受到影响,进而会影响整个生物链。在分析土壤重金属污染治理的现状及形态的基础上,指出土壤中重金属治理的方法,并提出相应的修复解决措施,以期能够最大限度地治理工业用地污染物,保障生物链的安全。  相似文献   

4.
重金属元素与稀土元素都有环境积累性,对动物的身体健康会造成一定程度的影响.此外,两者对土壤之间都有这很强的吸附能力,并且因为本身的化学性质决定,两者的降解速度十分缓慢.随着时间的推移,重金属与稀土元素的不断积累,将会影响土壤的生态功能.因此,要做好相应的调查工作,为我国地质理论、生态农业评价研究都有着关键作用.  相似文献   

5.
《价值工程》2017,(23):135-137
以某化工厂附近受Cd污染的土壤为研究对象,通过室内土柱淋洗实验方法,模拟土壤的实际环境,研究盐酸和乙二胺四乙酸(EDTA)对污染土壤中重金属Cd的去除效果。结果表明:在盐酸浓度为3 mol/L、EDTA浓度为0.04 mol/L的条件下,采用盐酸、EDTA、盐酸:EDTA 1:1和盐酸:EDTA 2:1四种配方,样品中Cd的去除率分别为64%、27%、36%和55%。采用盐酸作为淋洗剂均能取得所有配方中最高的Cd去除率,其中淋洗最大值主要集中在18-26h之间。  相似文献   

6.
李晓斌 《价值工程》2014,(22):325-326
通过再生铅项目的建设对土壤环境的影响评价,评述建设项目所在区域的土壤环境质量分级标准及评价区域环境土壤现状;从正常工况和非正常工况两方面预测污染物铅排放对土壤环境的潜在污染,并定量分析其危害程度;并指出铅排放对人体健康及植被、农作物的危害,提出污染防治措施和监测方案。  相似文献   

7.
测定了聊城市重点河流底泥中8种重金属(Cu、Cd、As、Pb、Cr、Zn、Ni和Hg)的浓度和受污染的底泥量,并用富集因子法和潜在生态危害法进行了风险评价,结合土壤、污泥的重金属污染修复技术,有针对性的提出污染底泥治理方案。  相似文献   

8.
重金属污染对人体的危害   总被引:4,自引:0,他引:4  
在环境与健康领域所说的重金属主要是指汞(Hg)、镉(Cd)、铬(Cr),以及具有重金属特性的类金属砷(As)等生物毒性显著的重元素,有时也泛指铜(Cu)、锌(Zn)、钴(Co)、镍(Ni)等一般重金属,其中有的尽管是人体健康所必需的微量元素,但在体内蓄积也有量的限度,超出这个限度同样显现出致病毒性.目前,学术界研究较多的是Hg、Cd、Cr和As等.  相似文献   

9.
针对城市表层重金属污染,以功能区的划分为切入点,运用Surfer软件将8种重金属元素等浓度线图和城市功能区分布图叠加获取8种重金属元素空间分布.建立正交因子模型比较因子得分函数中重金属污染物系数大小,确定各个功能区的主要重金属污染物.  相似文献   

10.
林建新 《价值工程》2010,29(27):225-225
有机氯农药作为一种高残留农药,虽经过二十多年的降解,土壤环境中的残留量仍十分可观,通过食物链富集仍可威胁到人体健康。本文总结了近年国内外对土壤中OCPs残留研究的最新成果,阐述了OCPs在我国土壤中的残留情况和生态毒性,并分析了影响其残留的因素。  相似文献   

11.
This paper outlines the ICT statistical developments that the ABS has undertaken over recent years. These developments have been on both the supply side (ICT industry) and the demand side (use of IT by sector). The content of ABS ICT surveys has changed significantly over the last few years and are expected to develop further in line with industry changes and emerging policy needs.
Recent developments in household collections have been the inclusion of IT use questions in the 2001 Census of Population and Housing and in various ABS social surveys such as Children's Participation in Culture and Leisure Activities. Annual business IT use surveys are now conducted and include topics such as Internet commerce and IT security. Biennial ICT industry surveys are conducted to provide data on ICT production, imports and exports, ICT industry employment, performance and structure information. An Internet activity survey is run every six months and provides regional Internet access details and infrastructure details on Internet service providers.
A major development for 2002–03 will be the compilation of an ICT satellite account. ABS intends to produce an ICT Information Development Plan to guide its future statistical development work in the ICT field.  相似文献   

12.
En este estudio se analiza el incumplimiento del salario mínimo durante el periodo 2003–2012 en diez países de Europa central y oriental con salario mínimo obligatorio nacional. A partir de los datos de EU‐SILC y la metodología propuesta por Bhorat, Kanbur y Mayet (2013), se cuantifica la incidencia y magnitud del incumplimiento. Se realizan análisis de regresión sobre determinantes individuales, laborales y macroeconómicos. Aunque la incidencia permanece relativamente baja, los trabajadores a los que se dirigen las políticas de salario mínimo parecen los más expuestos a su incumplimiento. Con el tiempo, una mayor incidencia se asocia a una razón más alta entre salario mínimo y salario medio.  相似文献   

13.
Several US counties and local governments have recently considered a novel solution to the foreclosure crisis. They plan to use eminent domain to compel the owners of mortgage debt—and specifically of private‐label mortgage‐backed securities—to sell the debt to the government at a price reflecting the loan's market value. The government would then restructure the debt and resell it to new investors. The plans are striking because—in contrast to both development‐driven eminent domain and the federal subprime bank bailout—they would force investors to assume asset devaluation and increased long‐term risk. Notably, the plans have emerged as an instance of financialization‐focused politics in suburbs and suburban cities of color, specifically majority‐black and ‐Latino/a suburbs. Local support for the plans, we argue, is rooted in the long‐term disinvestment of these ‘suburbs of exception', which became targets of subprime lending and eventually sites where the ‘financial exception' has been localized. But these demographic shifts, fragmentation and fiscal pressures have at the same time created a suburban political terrain in which the plans have gained their strongest political support.  相似文献   

14.
Serendipity – the notion of making surprising and valuable discoveries – plays a major role in the success of individuals and organizations alike. Previous research has established the importance of serendipity and identified important individual- and organizational-level antecedents. However, the literature has been dispersed and the boundaries of the concept have been blurry, leading to a lack of conceptual clarity and structure, and thus limiting validity and managerial actionability. Based on a systematic literature review, I synthesize existing management-related research on serendipity and explicate the emergence and composition of serendipity in the organizational context. I first identify three necessary conditions that differentiate serendipity from related concepts such as luck or targeted innovation: agency, surprise, and value. Then, I draw from the literature on sensemaking, event-based theorizing, and quantum-based approaches to management to conceptualize the process of cultivating serendipity in the organizational context as a process of enabling potentiality and materialization, and develop a multi-level theory of (cultivating) serendipity. This conceptualization contributes to our collective understanding of how, why, and when (i.e., under what conditions) organizations can leverage the value in the unexpected, which opens up fruitful avenues for further research.  相似文献   

15.
NGOs in Bangladesh have been recognized as effective change agents in the socio-economic arena throughout the world. Their contributions in micro credit, non-formal education and primary health care are widely known. NGOs play a significant role in society. NGO accountability, as a result, has become a critical issue. NGO accountability in Bangladesh has been examined here in relation to patrons, clients and themselves. Of the three relationships only accountability to patrons is in a near satisfactory state. Accountability to clients is handicapped by lack of opportunities of beneficiaries to participate meaningfully in NGO policy making. Accountability to themselves is adversely affected due to the adherence to a strictly hierarchical system and the influence of founding and charismatic NGO leaders.  相似文献   

16.
While a growing body of research analyses the functional mechanisms of the cultural or creative economy, there has been little attention devoted to understanding how local governments translate this work into policy. Moreover, research in this vein focuses predominately on Richard Florida's creative class thesis rather than considering the wider body of work that may influence policy. This article seeks to develop a deeper understanding of how municipalities conceptualize and plan for the cultural economy through the lens of two cities held up as model ‘creative cities’ — Austin, Texas and Toronto, Ontario. The work pays particular attention to how the cities adopt and adapt leading theories, strategies and discourses of the cultural economy. While policy documents indicate that the cities embrace the creative city model, in practice agencies tend to adapt conventional economic development strategies for cultural economy activity and appropriate the language of the creative city for multiple purposes.  相似文献   

17.
Despite the establishment of high-tech multinational enterprises (MNEs) in Ireland since the late 1950s, the country did not succeed in closing the technological gap with most of its EU counterparts. The weak National System of Innovation (NSI), and in particular low business and government R&D levels, combined with a lack of research and technology linkages between MNEs and indigenous firms, explain these poor results. However, the Shannon region in the West of the country presents some specific institutional characteristics that could theoretically make the region a strong technological enclave. The various actors in the region - i.e. the administrative, financial, political and research institutions, as well as the business organizations - have indeed infused a new type of economic development. After a brief review of the available concepts and models articulated around these actors and their interrelationships, the paper analyses whether the Shannon region, taken as an illustrative example, mirrors a specific economic and technological localized setting. The study is based on a survey of indigenous and foreign firms.  相似文献   

18.
This article reviews discrimination and diversity research published in Human Resource Management (HRM) over the past 60 years. While discrimination and diversity are very different constructs, it is often informative to study them together, because when people recognize each other's diversity, this can result in bias, stereotyping, and discrimination. We conducted bibliographic searches for terms related to discrimination and diversity as well as a manual search through every title and abstract published in HRM over the last 60 years to assess article relevance. The search resulted in 135 research articles with 136 unique studies (i.e., samples) which are reviewed in this article. Sex and race are the demographics that have been examined the most in HRM, while religion has been examined the least. Moreover, the number of studies examining lesbian, gay, bisexual, transgender, and queer (LGBTQ) employees in the workplace in HRM has grown quickly within the past 10 years, culminating in a recent meta‐analysis. Our review looks at some of the earliest research published, the most recent research published, and the overall trends we identified in the research over the years for both discrimination and diversity articles. We then make future research suggestions and recommendations to advance the study of discrimination and diversity in the coming years.  相似文献   

19.
There has been much discussion regarding the possible decline and weakening of national systems of human resource management (HRM). Yet, culture and institutions are often cited as the major stumbling blocks to this outcome. Such constraints may dissipate in the analysis, particularly if ‘regional clusters’ are considered where geographic and cultural closeness and ‘openness’ to similar economic pressures exist. In such cases, it might be postulated that convergence in HRM will occur. We argue that China, Japan and South Korea represent such a cluster. This article examines these countries, to see if a degree of convergence is taking place and if it is towards an identifiable ‘Asian’ model of HRM. A model of change is presented that distinguishes between levels of occurrence and acceptance. Details of the development and practice of HRM in each country are then set out. The article ends with a discussion and implications section and a brief conclusion.  相似文献   

20.
The Early History of the Cumulants and the Gram-Charlier Series   总被引:2,自引:0,他引:2  
The early history of the Gram-Charlier series is discussed from three points of view: (1) a generalization of Laplace's central limit theorem, (2) a least squares approximation to a continuous function by means of Chebyshev-Hermite polynomials, (3) a generalization of Gauss's normal distribution to a system of skew distributions. Thiele defined the cumulants in terms of the moments, first by a recursion formula and later by an expansion of the logarithm of the moment generating function. He devised a differential operator which adjusts any cumulant to a desired value. His little known 1899 paper in Danish on the properties of the cumulants is translated into English in the Appendix.  相似文献   

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