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161.
主体功能区域划分是有别于过去任何区划的创新性的工作,目前作为全国及各省的一项重要战略任务已经全面展开,但涉及具体县域单元的典型实证研究较为薄弱。随着中部崛起战略的提出和实施,中部安徽沿江地区正掀起开发沿江的高潮,迎来快速发展期。以安徽沿江地区无为、和县为实证区域,以乡镇为基本空间单元,以GIS为技术支撑,运用“生态 经济社会支撑力”互斥性矩阵分区方法,将县域开发的功能区划分为优先开发区域、鼓励开发区域、适度开发区域、引导开发区域和禁止开发区域5种类型。并根据功能分区的分类结论,确定出县域开发轴线、产业空间布局、生态保护轴线与保护框架。最后,在实证研究基础上,对确定县域开发轴线和生态保护轴线的思路以及县域功能分区的方法论基础进行了探讨。  相似文献   
162.
减排与适应协同发展研究:以广东为例   总被引:1,自引:0,他引:1  
减排和适应是全球应对气候变化的两大任务.发展中国家对气候变化不利影响的承受能力特别脆弱,同时面临着减排和发展任务,在资金有限的情况下,促使适应和减排联合行动能发挥协同效应,降低减排和适应成本,取得增量社会效益.适应分为增量型和发展型活动.在国家规定的减排和适应重点活动领域中,挑选出能源领域减排与增量型适应活动进行协同效应分析,至少有4个强协同效应和10个弱协同效应发生.以广东省为例,增量型适应活动和能源领域减排措施的协同效应主要体现在以下3个方面:工程性适应项目建设与低碳能源生产、消费的关联效应,提高能效有利于工程性适应项目的建设;海岸带适应措施增加碳汇和节约减排成本;城市绿化建设通过有目的的公共设施建设,缓解气候灾害对人们生活的直接影响,节约适应成本,同时增加碳汇和节约减排成本.减排和适应行动的联动机制是未来发展中国家研究的重点.  相似文献   
163.
中国低碳城市发展模式与行动策略   总被引:2,自引:0,他引:2  
建设低碳城市是促进节能减排和经济社会持续发展的重要战略举措,成为未来城市发展的重要导向和路径选择.从低碳城市发展重要性和紧迫性入手,在立足基本国情的基础上设计了低碳城市发展愿景.结合城市化快速推进预期和经济社会发展需求,分阶段提出了低碳城市发展目标.从总体模式、指导理念、基本思路、主要领域等对我国低碳城市发展模式进行了构想.在此基础上,提出我国低碳城市发展的实施步骤和行动策略.研究认为,我国低碳城市发展模式应选择“C”模式,以低碳发展为主导方向,以节能减排为发展方式,以低碳生产和低碳生活为主要方法.按照控源、减碳、增汇的基本思路,依靠理念创新、技术创新和制度创新,在低碳产业、低碳能源、低碳技术以及低碳生活等领域,通过构建低碳城市规划理论框架、建立低碳城市评价标准和体系、加快相关政策规章与制度建设、开展城市碳交易试点以及加强监督指导等措施,立足国情、统筹兼顾,分步骤、分阶段有序推进低碳城市发展.  相似文献   
164.
主体功能区划是协调我国当前经济快速发展与资源环境保护问题的有效途径之一。以位于经济快速发展的长江三角洲江苏宜兴市为例,在建立宜兴市主体功能分区评价指标体系的基础上,采用主成分分析法确定各评价因子权重,运用灰色关联投影模型分别计算资源环境约束、现有开发强度、未来发展潜力3个投影值并划分高、中、低3个等级;根据各镇资源环境 开发强度 发展潜力组合类型,利用三维魔方图分类法进行主体功能区划,将宜兴市划分为优化整合区、重点拓展区、适度发展区、农林优先区、生态保护区5个主体功能区,分区结果更加突出主体功能区从开发型到保护型逐步过渡的“主体功能”特性。此外,通过灰色关联投影模型计算出的评价样本投影值用模的大小和评价样本与理想样本间的夹角余弦的乘积表示,使得评价结果更为全面、准确  相似文献   
165.
The objective of this study was to measure the content of flavonoids, polyphenols, and carotenoids in the Helianthus annuus L. bee pollen. It was also to evaluate the ability of the dried, frozen, and freeze-dried extracts of sunflower (H. annuus) pollen, its scavenged free radicals and reducing action. Another aim of this study was to investigate the antimicrobial in vitro action of the H. annuus pollen extracts against the Gram-positive and Gram-negative bacteria and fungi. All pollen extracts showed medium antiradical activity and reductive ability. The most effective was the freeze-dried extract in both evaluation systems. The evaluation of the protective effects of DNA using a biosensor showed an opposite trending—frozen ? dried ? freeze-dried pollen. For the evaluation of antiradical activity, the DPPH method was used, and reductive ability was assessed by means of phosphomolybdic complex formation. The comparison of the polyphenols content shows higher values in freeze-dried bee pollen than in the dried and frozen pollen. The highest content of flavonoids was found in the frozen samples and the most carotenoids were present in the dried samples. In our study, the best antibacterial effects of the dried sunflower bee pollen extracts were found against Paenibacillus larvae, Pseudomonas aeruginosa, and Enterococcus raffinosus. The best inhibitory properties of the frozen sunflower bee pollen extracts were found against Escherichia coli, Pseudomonas aeruginosa, and Paenibacillus larvae. Very good inhibitory effects of freeze-dried sunflower bee pollen were found against Paenibacillus larvae, Brochotrix thermosphacta, and Enterococcus raffinosus. The best antifungal activity of the sunflower bee pollen was found in the frozen bee pollen extracts against Aspergillus ochraceus and freeze-dried bee pollen extracts against Aspergillus niger.  相似文献   
166.
A variance-based global sensitivity analysis (GSA) was applied to the dose assessment model used in the risk-based corrective action methodology of environmental risk analysis to identify key sources of variability and uncertainty and quantify the relative contribution of these sources to the variance of estimated dose. GSA was performed applying extended Fourier amplitude sensitivity test technique. The soil-to-air contaminant transport pathway within an inhalation exposure scenario was addressed. Three persistent semi-volatile carcinogenic chemicals, including polychlorinated biphenyls, benzo(a)pyrene, and 2,3,7,8-tetrachlorodibenzo-p-dioxin, were chosen as contaminants of concern.  相似文献   
167.
Integrated testing and intelligent assessment—new challenges under REACH   总被引:1,自引:1,他引:0  
BACKGROUND, AIM AND SCOPE: Due to a number of drawbacks associated with the previous regime for the assessment of new and existing chemicals, the European Union established a new regulation concerning the registration, evaluation, authorisation and restriction of chemicals (REACH). All relevant industrial chemicals must now be assessed. Instead of the authorities, industry itself is responsible for the risk assessment. To achieve better and more efficient assessments while reducing animal testing, all information-standard, non-standard and non-testing-has to be used in an integrated manner. To meet these challenges, the current technical guidance documents for risk assessment of new and existing chemicals had to be updated and extended considerably. This was done by experts in a number of REACH Implementation Projects. This paper presents the most relevant results of the expert Endpoint Working Group on Aquatic Toxicity in order to illustrate the change of paradigm in the future assessment of hazards to the aquatic environment by chemical substances. MAIN FEATURES AND CHALLENGES: REACH sets certain minimum data requirements in order to achieve a high level of protection for human health and the environment. It encourages the assessor to use alternative information instead of or in addition to standard one. This information has to be equivalent to the standard information requirement and adequate to draw overall conclusions with respect to the regulatory endpoints classification and labelling, persistent, bioaccumulative and toxic (PBT) assessment and predicted no-effect concentrations (PNEC) derivation. The main task of the expert working group was to develop guidance on how to evaluate the toxicity of a substance based on integration of information from different sources and of various degrees of uncertainty in a weight of evidence approach. INTEGRATED TESTING AND INTELLIGENT ASSESSMENT: In order to verify the equivalence and adequacy of different types of information, a flexible sequence of steps was proposed, covering characterisation of the substance, analysis of modes of action, identification of possible analogues, evaluation of existing in vivo and in vitro testing data as well as of QSAR results. Finally, all available data from the different steps have to be integrated to come to an overall conclusion on the toxicity of the substance. This weight of evidence approach is the basis for the development of integrated testing strategies (ITS), in that the available evidence can help to determine subsequent testing steps and is essential for an optimal assessment. Its flexibility helps to meet the different requirements for drawing conclusions on the endpoints classification and labelling, PNEC derivation as well as PBT assessment. The integration of all kinds of additional information in a multi-criteria assessment reduces the uncertainties involved with extrapolation to the ecosystem level. The weight of evidence approach is illustrated by practical examples. CONCLUSIONS AND PERSPECTIVES: REACH leads to higher challenges in order to make sound decisions with fewer resources, i.e. to move away from extensive standard testing to an intelligent substance-tailored approach. Expert judgement and integrated thinking are key elements of the weight of evidence concept and ITS, potentially leading to better risk assessments. Important sub-lethal effects such as endocrine disruption, which are not covered by the current procedure, can be considered. Conclusions have to be fully substantiated: Risk communication will be an important aspect of future assessments.  相似文献   
168.
选取污水中的污染物四环素和铜离子为二元混合物,以比吸磷率来表征二元混合物对污水生物除磷微生物的联合作用效应.采用直接均分射线法设计3种二元混合物的浓度配比(Ratio1,Ratio2,Ratio3);采用Logistic方程拟合试验数据获得浓度-效应曲线,并利用浓度加和模型分析二元混合物对生物除磷微生物的联合作用效应及...  相似文献   
169.
在个体水平上阐明环境雌激素类化合物对易受影响生物的联合毒性作用,探讨混合污染物联合作用和环境风险评价的研究方法.通过对鲫鱼血清卵黄蛋白原含量的相对变化和暴露浓度的非线性回归分析得出17α-乙炔基雌二醇(EE2)、17β-雌二醇(E2)、双酚A(BPA)、辛基苯酚(OP)及其等毒性混合物产生雌激素效应的剂量-反应关系,应用联合作用指数和相加作用模型研究4种环境雌激素的联合作用.各化合物非线性回归分析结果均以Weibull函数拟合效果最好,决定系数R2≥0.92;效应浓度值及其95%置信限通过自举抽样法得出,其中半效应浓度值EC50及其95%置信区间分别为0.0079(0.0068~0.0100)、0.0987(0.0900~0.1110)、63.50(56.58~70.62)和250.59(228.46~271.99)μg·L-1.4种环境雌激素混合物效应通过相加作用模型预测在全剂量范围内与实验结果相一致,呈现相似联合作用.相加作用模型是在各个浓度反应水平上展示化合物联合作用的性质,是切实可行的联合作用研究方法,而混合物效应通过联合作用指数评价存在许多不确定性.  相似文献   
170.
基于2007年中国投入产出表建立了包含产业内部关联波及效应和居民消费诱发效应的投入产出宏观闭模型.在此基础上测算大气污染防治行动计划(以下简称"计划")完全实施所需投资对京津冀、长三角、珠三角三大重点区域GDP、就业的正负效应及重点区域不同行业的影响,并对不同地区社会经济影响结果进行了比较分析.结果表明:在五年期间项目实施将拉动京津冀地区GDP增加35.66×108元,增加就业岗位约40808个;拉动长三角地区GDP增长2782.03×108元,增加就业岗位约238285个;拉动珠三角地区GDP增长852.85×108元,增加就业岗位约74758个.在短期(2013-2017年)内,长三角地区所获总收益远大于珠三角与京津冀地区.从行业影响看,三大地区实施"计划"后受益的行业主要集中于交通运输设备制造业、通用与专用设备制造业等与"计划"直接关联的行业.京津冀与长三角地区服务业所获得的直接效益远大于珠三角地区,侧面反映出珠三角地区服务业水平要整体高于长三角及京津冀地区;而珠三角和长三角地区因对交通行业投资较大,故交通运输设备制造业所获得的经济效益也要远大于京津冀地区.研究显示,不同地区投资所获的效益受到当地产业结构的影响,在未来产业发展中,京津冀地区应大力发展第三产业,对金属冶炼及压延加工业应多考虑产业结构升级优化;长三角及珠三角地区应鼓励发展新能源汽车、环保装备制造等行业.   相似文献   
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