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51.
Jeremiah Bohr 《环境政策》2016,25(5):812-830
Mainstream policy responses seek to utilize market mechanisms in an effort to minimize costs for major emitters of greenhouse gases. Presumably, this should win over some climate change deniers who align themselves with think tanks promoting free markets and economic growth. Yet, climate change deniers and free-market activists are as staunchly opposed to market-based climate policy as they are to any other form of climate mitigation. In order to understand why climate change deniers reject market-based policy proposals, an archive of free-market environmental newsletters was analyzed for themes of economic opposition. This analysis revealed how climate change deniers rely upon the concept of a regulatory cartel to connect economic opposition to climate policy with attacks on scientific evidence. Because professional scientists do not operate under conventional private-market incentive structures, neoliberal climate change deniers frame scientific knowledge as an attack on economic freedom when utilized to guide policy governing environment–economy relationships.  相似文献   
52.
用PCR方法检测溶血肠毒素BL、肠毒素T和肠毒素S三种肠毒素基因(hblA、becT、entS)及毒素调控基因plcR在30株苏云金芽胞杆菌株(Bt)中的分布.结果表明,含有hblA基因、entS基因、becT基因及plcR基因片段的Bt菌株分别占66.7%、70%、70%和73.3%.其中,含有plcR基因的菌株都至少含有一种肠毒素基因,不含肠毒素基因的菌株也未检测到plcR基因,说明plcR基因与肠毒素基因有着密切的关系.用3个Bt菌株WB9、HD2和HD9(都含有hblA、becT、entS和plcR基因片段,HD2和HD9经RPLA与TECRA肠毒素检测试剂盒检测具有高滴度)对小白鼠进行口服急性毒性试验.结果表明,所有3种供试菌株的发酵上清液对小白鼠行为和健康没有明显影响,对内部器官(心、肝、肺等)也没有产生病理现象.图5表3参14  相似文献   
53.
基因调控网络(gene regulatory network,GRN)是用于研究基因调控的一种新兴的系统生物学方法,尤其适合描述生物体早期发育的调控系统和机制。由于它能体现出调控过程的网络特性和动态关系,从整体的角度全面审视环境扰动所造成的真实影响,因此有望在内分泌干扰物等环境污染物的发育毒性机制研究中发挥重要作用,解决多年来一直困扰相关研究的种种难题。针对基因调控网络的结构、研究方法、应用成果和案例进行综述,并对将这一方法应用于污染物发育毒性机制研究的前景做出展望。  相似文献   
54.
应用外源生长调节物质是增强植物抗逆能力的有效手段之一.以黑麦草为受试植物,进行水培试验,探究外源基施0.1 mmol ·L-1亚精胺(Spd)对不同水平(0、5和10 mg ·L-1)镉(Cd)胁迫下黑麦草根系生理学和分子生物学两方面的影响.生理学研究结果表明,Cd胁迫显著降低黑麦草根系的生理机能,而添加Spd可有效缓解Cd引起的负面作用.其中对根系可溶性蛋白含量的影响最为显著,较5 mg ·L-1和10 mg ·L-1 Cd单独处理,分别提高了90.91%和158.35%.Spd还通过提高抗坏血酸(ASA)和谷胱甘肽(GSH)含量、过氧化物酶(POD)活性来抑制氧化胁迫产物丙二醛(MDA)和过氧化氢(H2O2)的积累,对根系活力和超氧化物歧化酶(SOD)活性的影响则不显著.分子生物学研究结果表明,10 mg ·L-1Cd胁迫致使黑麦草根部大量基因发生了差异表达,应用外源Spd后差异表达基因的数目、差异显著性和差异倍数均显著降低,GO富集分析最显著的部分由响应有机环状化合物、醛基/酮基转移酶活性变为响应三价铁离子和2''-脱氧麦根酸2''-双加氧酶活性.单基因表达热图分析发现,外源Spd上调了锌铁转运蛋白和2''-脱氧麦根酸2''-双加氧酶相关基因的表达,提高了根系对铁的吸收利用能力.综上所述,施用一定浓度的Spd可有效调控黑麦草根系对Cd胁迫的响应,增强其耐性生理,减轻Cd的毒害效应.  相似文献   
55.
The application of mandatory drinking water standards in Australia should ensure a basic water quality for all communities, with some standards written as a function of population. The main tenet of feasibility would be the capture of public benefits which foreseeably outweighed costs. Benefit-cost analysis can be a very valuable tool which aids in the decision process, however care must be taken to avoid institutional abuse or an over-positioned stature because of its applicative constraints.Many of the benefits associated with drinking water standards will often defy accurate itemization or monetization, and hence feasibility will frequently rely on approximations and a close analysis of case merits. Risk assessment is often used to estimate benefits accrued. Two common methods for valuing water quality are (a) cost of illness approaches, and (b) willingness to pay to avoid risk. The advantage of willingness to pay is that it engenders a larger interpretation of cost and quality value, and allows the community to rank preferences based on their willingness to avoid unnecessary risks.Given the technicalities and details in 'smart' water quality regulation which avoids unnecessary intrusion caused by ill-founded and unresolved clarity, lengthy drafting deliberations may often be necessary. The statutory and administrative structure of a future regulator is therefore a fundamental facet under-pinning the success of a comprehensive and responsive mandatory program. The process and rationale for regulatory development should be transparent and open, and this should include mandatory opportunities for public input during regulation drafting. Post inauguration mechanisms for suggestions on possible improvements and review of real world application should be considered important aspects of this process. Good models for comparison currently exist in the United States and Europe.  相似文献   
56.
A new series of 1, 3-Benzoxazines were synthesized, characterized (1H NMR and 13C NMR) and evaluated for their pesticidal activity. Six new 3-alkyl-3, 4-dihydro-4-methyl-2H-1, 3-benzoxazines (1-6) were prepared by hydroxymethylation of secondary amines with formaldehyde in 65–68% yields. These compounds were screened for there IGR activity against Spodoptera litura and for antifungal fungal activity in vitro against Sclerotium rolfsii ITCC 6181 by poisoned food technique. Insect Growth Regulatory (IGR) activity against Spodoptera litura showed that compound 3-Nonyl-3,4-dihydro-4-methyl-2H-1,3-benzoxazines was most effective as IGR with larval GI50 of 1.863 μ g/Insect. Compounds 3-Octyl-3,4-dihydro-4-methyl-2H-1,3-benzoxazines and 3-Decyl-3,4-dihydro-4-methyl-2H-1,3-benzoxazines were effective IGRs. Antifungal screening revealed that compound 3-Dodecyl-3, 4-dihydro-4-methyl-2H-1,3-benzoxazines, was highly effective against Sclerotium rolfsii with LC50 value 31.7 mg L?1 comparable with commercial fungicide Hexaconazole (LC50 1.27 mg L?1). Also compounds 3-Nonyl-3, 4-dihydro-4-methyl-2H-1,3-benzoxazines and 3-Decyl-3,4-dihydro-4-methyl-2H-1,3-benzoxazines displayed promising fungitoxicity. The results described in this paper are promising and provides new array of synthetic chemicals to be utilized as pesticides.  相似文献   
57.
The aim of this article is to propose a new analytical framework for comparing and explaining the emergence and diffusion of European regional mountain initiatives (ERMIs), envisaged as ‘functional regulatory spaces’ (FRS). The article examines three exploratory hypotheses. The first hypothesis considers that the different ERMIs (Alps, Pyrenees, Jura, Carpathian, Balkan Mountains, Dinaric Arc, Caucasus) can be compared, distinguished, and classified using the FRS approach. The second hypothesis addresses the relationship between the degree to which ERMIs correspond to an ideal-type FRS and their role and position within policy diffusion processes. We suggest that the more an ERMI corresponds to an ideal-type FRS, the more important is its role in diffusion processes. The third hypothesis focuses on the relationship between the degree of formalization and institutionalization of ERMIs and their role in policy diffusion processes. We argue that the more and the earlier an ERMI is “formalized” and “institutionalized” in a clear and robust way as a “mature” FRS, the more important its role, and the more central its position, in diffusion processes. This article is a very first attempt to link FRS and policy diffusion concepts. As such it seeks to assess the link's feasibility and relevance, rather than a definitive empirical (in)validation of the three hypotheses.  相似文献   
58.
为了从价值观和调节焦点的双重视角给煤矿企业新生代员工的安全管理提供科学依据,在文献研究和问卷调查的基础上,对 244 个有效样本进行分析,揭示煤矿企业新生代员工工作价值观的具体内容,结合动机理论和调节焦点理论,构建煤矿企业新生代员工工作价值观、调节焦点和安全绩效的结构方程模型。研究结果表明:煤矿企业新生代员工的工作价值观包含发展导向、自我导向、关系认同、独立自主、利益导向和创造导向6个因子结构;煤矿企业新生代员工的工作价值观、调节焦点和安全绩效两两之间均显著相关;煤矿企业新生代员工的工作价值观不仅可以直接预测安全绩效,还可以通过调节焦点的中介作用间接影响煤矿员工的安全绩效。  相似文献   
59.
60.
Although theory suggests that regulatory focus fluctuates within person and such fluctuations impact employee well‐being, there is little empirical investigation of such propositions. These are important research questions to address because work events may elicit within‐person fluctuations in regulatory focus, which can then affect well‐being. The primary purpose of this study is to examine specific predictors of daily regulatory focus at work and the foci's impact on employee well‐being at work and home as indicated by mood and psychosomatic complaints, respectively. We present and test an overarching theoretical framework that integrates conservation of resources theory, the cognitive‐affective processing system framework, and regulatory focus theory to delineate why and when work events affect regulatory focus and how the foci affect well‐being. Consistent with our expectations, we found that positive work events positively predicted daily promotion focus, but this effect was weaker when employees had high‐quality relationships with leaders. Furthermore, daily regulatory focus was associated with employee well‐being (mood and psychosomatic complaints) such that (i) promotion focus improved well‐being; (ii) prevention focus reduced well‐being; and (iii) the effects of promotion focus on well‐being were strongest when prevention focus was low. We discuss theoretical and practical implications and offer directions for future research. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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