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651.
Since the adoption of community right-to-know programs in the US there has been an increase in the number of groups known as local emergency planning committees. These committees have matured in focus over the intervening years since the Bhopal incident and even more so since the events of September 11, 2001. There is a strong recognition that local communities working very closely with chemical handling facilities in their areas can directly and meaningfully reduce the threat of a chemical release incident, regardless of cause. Likewise, through similar means they can better prepare themselves to respond should an incident occur. Especially as regards modern concepts of process chemical safety and facility security, local communities can be of great assistance to smaller facilities that do not otherwise necessarily have the resources to accomplish these tasks. As the vulnerabilities of a facility to accident or intentional act, the impacts of these events and the ability of communities to react are all a function of local conditions, it is clear that these local efforts can be more meaningful than large-scale national efforts. While national legislation is certainly helpful to the process of bringing people together, it is the local relationships that produce results. 相似文献
652.
Townsend T Dubey B Tolaymat T Solo-Gabriele H 《Journal of environmental management》2005,75(2):105-113
Disposal of discarded chromated copper arsenate (CCA)-treated wood in landfills raises concerns with respect to leaching of preservative compounds. When unweathered CCA-treated wood is leached using the toxicity characteristic leaching procedure (TCLP), arsenic concentrations exceed the toxicity characteristic (TC) limit of 5mg/L in most cases. The majority of discarded CCA-treated wood, however, results from demolition activities, where the wood has typically been subjected to weathering. Since preservatives do migrate from the wood during its normal use, leaching characteristics of weathered and aged CCA-treated wood may differ from unweathered wood. To evaluate this, CCA-treated wood removed from service after various degrees of weathering was collected from multiple sources and leached with the TCLP, the synthetic precipitation leaching procedure (SPLP) and California's waste extraction test (WET). Five to seven individual pieces of wood were analyzed from each source. The average TCLP arsenic concentration for the 14 sources ranged from 3.2 to 13 mg/L. The average TCLP concentrations of the 100 wood pieces tested were 6.4, 5.9 and 3.2 mg/L for arsenic, copper and chromium, respectively. Overall, in 60 out of 100 samples tested by the TCLP, arsenic concentrations exceeded 5 mg/L (the TC regulatory value). SPLP leachate concentrations were similar to TCLP concentrations, although copper leached somewhat more with the TCLP. WET leachate concentrations were approximately a factor of 10 higher than TCLP concentrations. Discarded CCA-treated wood, even after exposure to years of weathering, often exceeds the TC limit for arsenic and without the current regulatory exemption would possibly require management as a TC hazardous waste in the US. 相似文献
653.
Why do managers employ certain tactics when they try to influence others? This study proposes and tests theoretical linkages between the five‐factor model of personality and managers' upward influence tactic strategies. Longitudinal data from 189 managers at 140 different organizations confirmed that managers scoring high on extraversion were more likely to use inspirational appeal and ingratiation; those scoring high on openness were less likely to use coalitions; those scoring high on emotional stability were more likely to use rational persuasion and less likely to use inspirational appeal; those scoring high on agreeableness were less likely to use legitimization or pressure; and those scoring high on conscientiousness were more likely to use rational appeal. Results also confirmed that managers' upward influence tactic strategies depended on the leadership style of their target (their supervisor). Managers were more likely to use consultation and inspirational appeal tactics when their supervisor was a transformational leader, but were more likely to use exchange, coalition, legitimization, and pressure tactics when their supervisor displayed a laissez‐faire leadership style. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
654.
Timothy R. Lazaro 《Journal of the American Water Resources Association》1976,12(1):101-107
ABSTRACT. In order to demonstrate the feasibility of a nonparametric statistical application in investigating the hydrologic impact of the rapid land use change accompanying intense urbanization, annual maximum peak flow data from an actual example (the Northeast Branch Basin, a recently urbanized Washington, D.C., suburban watershed) were analyzed. Annual peak flow data from the Patuxent Basin above Unity, Maryland, a rural watershed in close proximity to the study area, were compared to data from the Northeast Branch for the Same period utilizing the Wilcoxon matched-pairs signed-ranks test. A change in central tendency of each series was noted at the 0.01 significance level; however, the change was negative in the rural basin and positive in the urbanized Northeast Branch Basin. This central tendency change was considered indicative of an average decrease in the size of rainstorms producing annual maximum peak discharges. Rainstorm data from the Northeast Branch Basin were divided into two equal periods (before urbanization and after) and the Wilcoxon test was applied. It was found that rainstorms producing maximum annual peak discharges in the urbanized period were indeed smaller than those in the prior period (0.01 level of significance); however, larger annual peaks were produced. It was concluded that nonparametric statistical methods can be used readily with conventional methods to isolate and clearly analyze the various problems in an actual urban hydrologic study. 相似文献
655.
Stephen M. Born Kenneth D. Genskow Timothy L. Filbert Nuria Hernandez-Mora Matthew L. Keefer Kimberly A. White 《Environmental management》1998,22(3):359-370
/ There are tens of thousands of small dams in the United States; many of these aging structures are deteriorating. Governments and dam owners face decisions regarding repair or removal of these structures. Along with the many benefits society derives from dams and their impoundments, numerous recent ecological studies are revealing the extensive alteration and degradation of river ecosystems by dams. Dam removal-a principal restoration strategy-is an infrequent event. The major reasons for removal have been public safety and the high costs associated with repair; the goal of river ecosystem restoration now warrants greater attention. Substantial study is being given to the environmental aspects of dams and dam removals, but very little attention has been given to the socioeconomic and institutional dimensions associated with the removal of dams, although these factors play a significant role in the removal decision-making process. Based on a case study of dam removals in Wisconsin-where more than 30 of the state's 3600 small dams have been removed in the past few decades-legal, financial, and socioeconomic issues associated with dam removal are documented and assessed. Dam removal has been complex and contentious, with limited community-based support for removal and loss of the impounded waters. In cases examined here, the estimated costs of repairing a dam averaged more than three times the cost of removal. The availability of governmental financing has been a key determinant in removal decisions. Watershed-scale ecological considerations are not major factors for most local interests. As watershed management and restoration increasingly include dam removal options as part of an integrated strategy, more attention will need to be focused on socioeconomic factors and stakeholder perspectives-variables that strongly influence the viability of this management alternative.KEY WORDS: Dam removal; River restoration; Institutions; Stakeholders 相似文献
656.
657.
658.
Timothy J. Downs 《Journal of Environmental Planning and Management》2000,43(5):601-621
Complex relationships exist between human nature and needs, cultural evolution and ecological dynamics. The purpose of this paper is to present a working hypothesis that explores how we may reverse worsening underdevelopment, poverty and unsustainability trends world-wide. Empirical evidence from cultural history and contemporary project experience are used to suggest a development process that combines three critical dimensions: ethics, productive social interaction and knowledge integration. Logic dictates that the process should be applied in any given country to mobilize investment in supplies of natural, human and economic capital, principally biodiversity, soil and water conservation, education and public health. A sociopolitical theory of underdevelopment is presented to suggest that unethical virtual cartels control social interaction, knowledge integration and resource mobilization, precipitating negative feedback effects on human development, ecological stability and, ultimately, cultural evolution. The hypothesis was formulated using observations over 5 years in Mexico and case-study experience to initiate an alternative process of water resource conservation. 相似文献
659.
James H. Matis Thomas R. Kiffe Wopke van der Werf Alejandro C. Costamagna Timothy I. Matis William E. Grant 《Ecological modelling》2009
Density dependent feedback, based on cumulative population size, has been advocated to explain and mathematically characterize “boom and bust” population dynamics. Such feedback results in a bell-shaped population trajectory of the population density. Here, we note that this trajectory is mathematically described by the logistic probability density function. Consequently, the cumulative population follows a time trajectory that has the same shape as the cumulative logistic function. Thus, the Pearl–Verhulst logistic equation, widely used as a phenomenological model for density dependent population growth, can be interpreted as a model for cumulative rather than instantaneous population. We extend the cumulative density dependent differential equation model to allow skew in the bell-shaped population trajectory and present a simple statistical test for skewness. Model properties are exemplified by fitting population trajectories of the soybean aphid, Aphis glycines. The linkage between the mechanistic underpinnings of the logistic probability density function and cumulative distribution function models could open up new avenues for analyzing population data. 相似文献
660.
Maria de Lourdes Melo Zurita Brian Cook Dana C. Thomsen Paul G. Munro Timothy F. Smith John Gallina 《Disasters》2018,42(3):571-589
This paper explores how social networks and bonds within and across organisations shape disaster operations and strategies. Local government disaster training exercises serve as a window through which to view these relations, and ‘social capital’ is used as an analytic for making sense of the human relations at the core of disaster management operations. These elements help to expose and substantiate the often intangible relations that compose the culture that exists, and that is shaped by preparations for disasters. The study reveals how this social capital has been generated through personal interactions, which are shared among disaster managers across different organisations and across ‘levels’ within those organisations. Recognition of these ‘group resources’ has significant implications for disaster management in which conducive social relations have become paramount. The paper concludes that socio‐cultural relations, as well as a people‐centred approach to preparations, appear to be effective means of readying for, and ultimately responding to, disasters. 相似文献