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321.
Climate change potentially brings continuous and unpredictable changes in weather patterns. Consequently, it calls for institutions that promote the adaptive capacity of society and allow society to modify its institutions at a rate commensurate with the rate of environmental change. Institutions, traditionally conservative and reactive, will now have to support social actors to proactively respond through planned processes and deliberate steps, but also through cherishing and encouraging spontaneous and autonomous change, as well as allowing for institutional redesign. This paper addresses the question: How can the inherent characteristics of institutions to stimulate the capacity of society to adapt to climate change from local through to national level be assessed? On the basis of a literature review and several brainstorm sessions, this paper presents six dimensions: Variety, learning capacity, room for autonomous change, leadership, availability of resources and fair governance. These dimensions and their 22 criteria form the Adaptive Capacity Wheel. This wheel can help academics and social actors to assess if institutions stimulate the adaptive capacity of society to respond to climate change; and to focus on whether and how institutions need to be redesigned. This paper also briefly demonstrates the application of this Adaptive Capacity Wheel to different institutions.  相似文献   
322.
MAP沉淀法目标产物最优形成条件及分析方法   总被引:14,自引:1,他引:13  
为了确定鸟粪石(MAP:MgNH4PO4·6H2O)形成的最优条件,引入化学剖析法,利用酸溶液将鸟粪石沉淀法中所得沉淀物溶解后进行相应的元素分析;提出一种根据沉淀物中的NH+4-N含量间接计算确定鸟粪石含量(即纯度)的分析方法.根据这种计算分析方法,分别得出了不同pH条件下以自来水(主要为地下水)和超纯水作为溶剂所合成的鸟粪石纯度,并对pH和Ca2+在鸟粪石形成过程中的影响进行了评估.结果表明,该计算分析方法能够有效实现对MAP沉淀法目标产物的定量分析,弥补了国内外目前普遍依靠XRD技术定性判断所得沉淀物中鸟粪石是否存在的缺陷.以超纯水作为溶剂时,使鸟粪石纯度>90%的最佳pH范围在7.5~9.0,而以自来水为溶剂时,获得相同鸟粪石纯度最佳pH范围则是7.0~7.5.实际污水中常常含有相当数量的Ca2+,实施碱性条件(pH>8.0)的MAP沉淀势必大幅降低鸟粪石的纯度.因此,对实际污水回收磷而言,MAP沉淀法的最优pH条件应控制在中性范围(<8.0)以内.  相似文献   
323.
Given the expansion of payments for water‐based ecosystem services (PWES) worldwide, two relevant issues are as follows: (1) determination of efficient allocations of payments among land managers, and (2) how this might change when paying one manager to implement a best management practice (BMP) to enhance an ecosystem service impacts the cost‐effectiveness of BMPs considered by other land managers not currently involved in PWES. Such externalities may be negative if diminishing returns dominate, or positive if mechanisms such as “social diffusion” dominate. We analyze how a planner should optimally allocate payments, depending on whether the expected externalities are negligible, negative, or positive. We employ (1) an optimal control model to gain insights on the problem’s dynamics, and (2) stochastic dynamic programming to determine optimal funding strategies using a specific application. The study contributes to the literature by identifying dynamically optimal PWES payment patterns, and illustrates how they should change when one accounts for externalities induced by the program. Because such impacts have not been addressed previously in a rigorous way, this treatment provides useful value added for PWES design and implementation.  相似文献   
324.
The climate change problem calls for a continuously responding society. This raises the question: Do our institutions allow and encourage society to continuously adapt to climate change? This paper uses the Adaptive Capacity Wheel (ACW) to assess the adaptive capacity of formal and informal institutions in four sectors in the Netherlands: spatial planning, water, agriculture and nature. Formal institutions are examined through an assessment of 11 key policy documents and informal institutions are analysed through four case studies covering each sector. Based on these ACW analyses, both sector-specific and more general strengths and weaknesses of the adaptive capacity of institutions in the Netherlands are identified. The paper concludes that the most important challenge for increasing institutional adaptive capacity lies in combining decentralized, participatory approaches with more top-down methods that generate leadership (visions, goals) standards, instruments, resources and monitoring.  相似文献   
325.
In this study, we look at the evolution of a cooperative water regime in the delta of the Rhine catchment. In a Dutch–German case study, we focus on cross-border cooperation on the local and regional scale, describing and analyzing how a remarkably resilient and robust transboundary water regime has evolved over the course of 50 years. Context-, interest- and knowledge-based explanations contribute important insights into the evolution of the Deltarhine regime, and it is shown that the legal, institutional and socio-economic context shapes and constrains regional cross-border cooperation. Surprisingly in this regard, we find that European water directives have not yet played a decisive, catalyzing role for policy harmonization across borders. Finally, we show that key individuals play a crucial role in regime formation and development. We suggest that the presence of entrepreneurs and leaders adds explanatory power to current conceptual frameworks in international river basin management, thus meriting further research.  相似文献   
326.
327.
This study examines vigilance as a behavioural indicator of the importance of infanticide risk by comparing the infanticide avoidance hypothesis with the predation avoidance and mate defence hypotheses for wild Thomas's langurs (Presbytis thomasi) in Sumatra. We found that all individuals were more vigilant in situations of high predation risk, i.e. lower in the trees and in the absence of neighbours. Females were also more vigilant on the periphery of the group. However, there were variations in vigilance levels that could not be accounted for by the predation avoidance hypothesis. Males without infants showed higher levels of vigilance in areas of home range overlap than in non-overlap areas during the early phase of their tenure, strongly suggesting mate defence. In these areas of home range overlap where Thomas's langur groups can interact, males may attack females and infants, and so the infanticide risk for males and females with infants is likely to be high in these areas. Only females with infants, but not males with infants or females without infants, showed higher vigilance levels in overlap areas than in non-overlap areas; in addition, in overlap areas, females with an infant were more vigilant than females without an infant, while this was not the case in non-overlap areas. Both females and males with infants were more vigilant high in the trees than at medium heights in overlap areas but not elsewhere. These findings can only be explained by the infanticide avoidance hypothesis. In contrast to predator attacks, infanticidal male attacks come from high in the canopy, and only occur in overlap areas. There was a significant sex difference in vigilance, but males were only more vigilant than females without an infant, and not more vigilant than females with an infant. We conclude that vigilance varied mainly in relation to the risk of predation and infanticide. Mate competition only played a role for males during the early phase of their tenure. Predation risk seems to offer the best explanation for vigilance for all individuals in the absence of infants. Both predation risk and infanticide risk played a role for females and males with infants. Received: 4 April 1998 / Accepted after revision: 6 September 1998  相似文献   
328.
The Dutch Ministry of Social Affairs and Employment provided subsidy over the period 2004–2008 to a number of companies to introduce changes aimed at reducing accidents by changing their safety culture and aspects of their safety management. As part of the programme a scientific evaluation was set up to assess the effectiveness of the interventions in 17 of the projects, covering 29 companies. Before and after studies were made of the companies, documenting the state of their safety management and risk control efforts and their accident rates before the intervention, the changes made over the study period and the resulting changes in a range of measures aimed at assessing the success of the changes. The analysis led to a categorisation of the projects according to their degree of success.This paper describes the patterns of interventions distinguishing between successful and not successful projects and discusses the mechanisms lying behind them. Interventions bringing about constructive dialogue between shop-floor and line management, providing motivation to line managers and strengthening the monitoring and learning loops in the safety management system (SM) appeared more successful. The amount of energy and creativity injected by top managers and, above all, by the coordinator (safety professional) appeared also to be a distinguishing factor.  相似文献   
329.
Innovative behavior is increasingly important for organizations' survival. Transformational leadership, in contrast to transactional leadership, has been argued to be particularly effective in engendering follower innovative behavior. However, empirical evidence for this relationship is scarce and inconsistent. Addressing this issue, we propose that follower psychological empowerment moderates the relationship of transformational and transactional leadership with follower innovative behavior. In a field study with 230 employees of a government agency in the Netherlands combining multisource ratings, we show that transformational leadership is positively related to innovative behavior only when psychological empowerment is high, whereas transactional leadership has a negative relationship with innovative behavior only under these conditions. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
330.
This paper discusses the method used for an outlook on road safety in the Netherlands until 2020. The objectives of the outlook are to judge the feasibility of the Dutch road safety policy targets and to estimate the effects in 2020 of new measures. The outlook consists of baseline forecasts assuming the unchanged continuation of the effect of current road safety policy as a starting point, and the effect of new measures on top of that. We used four different mobility scenarios, derived from a comprehensive study about the macro-economic development of Dutch society until 2040. In the mobility scenario with the largest growth it appeared doubtful whether the policy targets of that time for the maximum number of fatalities in 2020 (580) can be achieved. An extensive inventory of new measures after 2010 produced five already intended new measures, the effects of which were estimated. The results show that the target of maximum 580 fatalities in 2020 can probably be met. The recently adjusted policy target of 500 fatalities in 2020 is also feasible if additional new measures are taken.  相似文献   
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