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71.
Research and education tend to concentrate in specific geographical areas, while many jurisdictions receive limited federal research funding. This has resulted in reduced opportunity for students as well as limited ability of science to influence solving problems at the jurisdiction level. The National Science Foundation’s Experimental Program to Stimulate Competitive Research (EPSCoR) was intended to address the “undue concentration of research and education” by providing direct funding to improve research infrastructure, hire researchers, develop outreach, and to enhance local research capacity. Despite many successful outcomes attributed to EPSCoR, the aim and the execution of the program have generated controversy. Decision analytic tools can provide a systematic approach to EPSCoR prioritization that improves transparency and addresses the program’s intent. The wording of NSF’s mission and EPSCoR legislation suggest the intent of maximizing NSF’s benefit to the nation by directly supporting scientific research product across all jurisdictions and by supporting development of competitive scientific capabilities within particular jurisdictions. These components may be quantified via data-driven metrics producing indicators of ultimate benefit. Using illustrative scenarios within a multi-criteria decision model, we explore how such decision models may generate insights and how their guidance compares with current eligibility determinations.  相似文献   
72.
Male fiddler crabs Uca musica sometimes build sand hoods and male Uca beebei sometimes build mud pillars next to their burrows to which they attract females for mating. Mate-searching females preferentially approach these structures and subsequently mate with structure builders. Here we show that the preference for structures is not species-specific and argue that it may not have evolved for mate choice. When not near burrows, many species of fiddler crabs approach and temporarily hide near objects, suggesting that hoods and pillars may attract females because they elicit this general predator-avoidance behavior. To test this sensory trap hypothesis we individually released female U. musica, U. beebei and Uca stenodactylus, a non-builder, in the center of a circular array of empty burrows to which we added hoods and pillars and then moved a model predator toward the females. All species ran to structures to escape the predator and the two builders preferred hoods. Next, we put hood replicas on male U. beebei burrows and pillar replicas on male U. musica burrows. When courted, females of both species preferentially approached hoods as they did when chased with a predator. However, males of both species with hoods did not have higher mating rates than males with pillars perhaps because hoods block more of a male's visual field so he sees and courts fewer females. Sexual selection may often favor male signals that attract females because they facilitate general orientation or navigation mechanisms that reduce predation risk in many contexts, including during mate search.  相似文献   
73.
In 1991/1992, we studied the sand disposal behavior of the painted ghost crabs Ocypode gaudichaudii on the Pacific coast of Panamá. O. gaudichaudii either kick, dump or tamp sand they excavate from their burrows. Here we relate these three kinds of sand disposal to burrow structure and distribution, as well as to crab size and sex. Our objective was to determine whether tamping may be a male courtship signal. Burrows whose owners tamped sand were on average longer, deeper, and higher on the beach than were burrows whose owners kicked or dumped sand. Five burrow shapes were distinguished, with half-spiral and spiral shapes being most common among tamped burrows. All crabs excavated from tamped burrows were males. Tamped burrows peaked in abundance around full and new moons. These observations, together with what is known about mating and breeding behavior of other ghost crabs, suggest that tamping may be involved in O. gaudichaudii courtship.  相似文献   
74.
Compared with birds, mammals, fish, and even amphibians, very little is known about the effects of contaminants on reptiles. Recent evidence that many reptile populations may be declining has stimulated demand for toxicological studies of reptiles as well as development of nondestructive sampling techniques useful for assessing and monitoring contaminant exposure. The current study experimentally evaluated the utility of shed skins, tail clips, and blood samples as nondestructive indices of trace element exposure in banded water snakes, Nerodia fasciata. For 13.5 months, snakes were either fed fish from a coal ash-contaminated site or uncontaminated food from a reference site. Snakes fed contaminated prey accumulated As, Cd, Se, Sr, and V in various organs (i.e. liver, kidney, and/or gonads). Moreover, non-parametric discriminant function analysis revealed that snakes could be placed in two groups that reliably reflected their experimental diet based upon Se, Sr, and As concentrations in tail clips, blood, and/or shed skins. We suggest that nondestructive sampling techniques, particularly analyses of blood and tail clips, may be easily applied in evaluations of contaminant exposure in the field and laboratory and may prevent excessive destructive sampling of potentially threatened reptile species.  相似文献   
75.
Ecological risk assessments of pharmaceuticals are currently difficult because little-to-no aquatic hazard and exposure information exists in the peer-reviewed literature for most therapeutics. Recently several studies have identified fluoxetine, a widely prescribed antidepressant, in municipal effluents. To evaluate the potential aquatic toxicity of fluoxetine, single species laboratory toxicity tests were performed to assess hazard to aquatic biota. Average LC(50) values for Ceriodaphnia dubia, Daphnia magna, and Pimephales promelas were 0.756 (234 microg/l), 2.65 (820 microg/l), and 2.28 microM (705 microg/l), respectively. Pseudokirchneriella subcapitata growth and C. dubia fecundity were decreased by 0.044 (14 microg/l) and 0.72 microM (223 microg/l) fluoxetine treatments, respectively. Oryias latipes survival was not affected by fluoxteine exposure up to a concentration of 28.9 microM (8.9 mg/l). An LC(50) of 15.2 mg/kg was estimated for Chironomus tentans. Hyalella azteca survival was not affected up to 43 mg/kg fluoxetine sediment exposure. Growth lowest observed effect concentrations for C. tentans and H. azteca were 1.3 and 5.6 mg/kg, respectively. Our findings indicate that lowest measured fluoxetine effect levels are an order of magnitude higher than highest reported municipal effluent concentrations.  相似文献   
76.
ABSTRACT: The purpose of this study was to evaluate the Better Assessment Science Integrating Point and Nonpoint Sources (BASINS) watershed management system. BASINS data were used with the NPSM model to predict discharge and sediment concentrations at the outlet of a 103 km2 Ohio watershed. It was concluded that the NPSM model should always be calibrated but only a few of the parameters provided with BASINS needed to be calibrated. For a three‐year study period, there was a 2 percent underestimation of discharge using area weighted precipitation values and a 25 percent overestimation using the single station data in BASINS. A comparison of observed and predicted monthly discharge resulted in an r2 of 0.86 with area‐weighted precipitation and an r2 of 0.74 with the single station data. Calibrating the model to substantially improve sediment predictions was unsuccessful and we concluded that a calibration period of one year was too short. For the three‐year study period, the r2 for sediment was 0.36 with a slope of 0.37 and an intercept of 18.8 mg/l. The mean observed and predicted sediment concentrations were 27.1 mg/l and 22.6 mg/l, respectively.  相似文献   
77.
Acoustic Doppler Current Profilers (ADCPs) are now used routinely by physical oceanographers. A by-product of the signal processing for calculating the Doppler shift used to determine current velocity is the intensity of the acoustic backscatter, and this, in turn, is a measure of biomass. ADCPs can therefore potentially provide biological oceanographers with quantitative information, collected routinely and non-intrusively in near real time. If these acoustic measurements are obtained concurrently with hydrographic data, the possibility of collecting quantitative biological information on the same time and space scales as physicochemical data becomes a reality. ADCPs have been routinely operated on NERC ships for several years. Examples of the types of biological information which can be obtained are described here in the hope that this will stimulate other users to make use of a potentially valuable source of data.  相似文献   
78.
79.
Despite the commonly held belief that a protean career orientation (PCO) enables employees to achieve more balance in their lives, little is known about the relationship between PCO and work–life balance. Using two waves of data collection separated by 2.5 years, this study examined the relationship between PCO and work–life balance among a sample of 367 college‐educated employees in the United States. Analysis was conducted to empirically distinguish PCO from conceptually related constructs, and structural equation modeling was used to examine the process that explains the linkage between PCO and balance. We found that PCO was positively related to work–life balance. We also found support for the role of several resources (social capital, psychological capital, and perceived employability) that explain the relationship between PCO and balance. In particular, PCO was associated with extensive career planning activities that were related to the accumulation of three forms of career capital—human capital, social capital, and psychological capital. In turn, social capital and psychological capital were associated with high employability, which was related to greater work–life balance for individuals who take a whole‐life perspective on their careers. We discuss the theoretical and practical implications of the findings and provide suggestions for future research. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
80.
SUMMARY

What is sustainable development? Why is at an issue? Ideally, what needs to be done? and Practically, what can be done? are answered here by relying on the cultural theory of Mary Douglas and her colleagues, more especially Aaron Wildavsky and Michael Thompson, both of whom have used the model to address sustainable development. The implications of cultural theory for sustainable development are substantial.

The article is divided into five sections. The first describes the current controversy over sustainable development. The second sets out the cultural theory model, and the third applies that model to reformulate our understanding of sustainable development. The fourth draws out the implications of a reformulated sustainable development, while the conclusion uses those implications to answer the four questions that started the article.  相似文献   
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