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271.
The challenges of achieving successful inter‐agency logistic coordination in preparing for and responding to natural disasters and complex emergencies are both well understood and well documented. However, although many of these challenges remain unresolved, the literature reveals that the organisations that form the urban search and rescue (USAR) community have attained a high level of coherence and interoperability that results in a highly efficient and effective response. Therefore, this paper uses the idea of ‘borrowing’ from other fields as it explores how the processes and procedures used by the USAR community might be applied to improve humanitarian logistic operations. The paper analyses the USAR model and explores how the resultant challenges might be addressed in a humanitarian logistic context. The paper recommends that further research be undertaken in order to develop a modified USAR model that could be operationalised by the international community of humanitarian logisticians.  相似文献   
272.
For the first time, organochlorine (OC) contaminants were measured in blubber biopsies from free-ranging St. Lawrence River Estuary beluga whales (Delphinapterus leucas), to compare contaminant levels to those previously measured in dead stranded belugas. PCBs, DDTs, toxaphene and chlordane-related compounds were the major OC contaminants detected in 44 belugas biopsied in 1994-1998. SigmaPCB (the sum of 104 congeners) ranged from 2080 to 128,000 ng/g lipid in males (n=34; minimum estimated ages 8-22 years), and from 148 to 44,100 ng/g lipid in females (n=10; minimum estimated ages 7-22 years). The concentrations of PCBs and OC pesticides in the blubber of these whales overlapped those observed in stranded belugas from an earlier study, and demonstrated comparable age and sex-related trends. However, lower proportions of mirex, HCB, DDTs, and many of the highly chlorinated PCBs occurred in the biopsy samples compared to results for blubber from stranded carcasses. Most major OC compounds were present at lower concentrations in the biopsies, but this does not appear to be solely related to age differences between the two groups, or to emaciation in the stranded whales. Nor does it appear to be associated with the use of superficial biopsies, and the possible stratification of lipids and OCs in the blubber layer. Nevertheless, given these possible confounding factors, and the uncertainty in age estimates for the biopsied whales, the results point to the need for careful interpretation of biopsy results when comparing with data taken from the full depth of the blubber mantle in stranded whales. Taken together, results from both biopsied whales and previously studied stranded belugas indicate that PCB and OC pesticide contamination of St. Lawrence beluga whales may occur across a broader range of levels than previously thought, at least for males which formed the largest group in this study, possibly due to different degrees of dietary exposure. It also appears that measuring contaminant concentrations only in stranded whales, may overestimate OC levels in the population as a whole, especially for highly chlorinated OCs.  相似文献   
273.
The C-Lock system was developed to address the need for an improved method of quantifying and certifying project-level carbon emission reduction credits (CERC). It was designed to enable individual landowners to efficiently quantify, certify, pool, market and trade CERCs generated by agricultural management practices. We provide a general overview of the C-Lock system as it has been implemented for the USA State of South Dakota. C-Lock is comprised of four linked components: a web interface, a client database, a Geographic Information System (GIS) database of soil, climate and generalized land use history parameters, and the CENTURY soil carbon model. The user-friendly interface elicits generalized land-use and crop history information from the client from 1900 through 1989, then explicit annual information from 1990 onward. A climate-zone level landuse and crop management database is used to fill in gaps in the client-provided data. These data are used to drive the CENTURY model, which estimates annual changes in soil carbon stocks. Monte Carlo simulation is used to estimate uncertainty bounds, and these are applied to the CENTURY outputs in order to provide probabilistic estimates of accrued CERCs in a manner that is transparent and verifiable. In a demonstration application, CERCs are estimated for three different land-use scenarios on a representative field in eastern South Dakota: reduced tillage or conservation (no-till) management of a corn (maize)/wheat/soybean rotation, and enrollment in the Conservation Reserve Program, which entails establishing permanent grass cover. The credits are based on a business-asusual scenario of conventional tillage.  相似文献   
274.

The distinct role of subnational governments such as states and provinces in addressing climate change has been increasingly acknowledged. But while most studies investigate the causes and consequences of particular governments’ actions and networking activities, this article argues that subnational governments can develop climate action as a collective entrepreneurial activity. Addressing many elements explored in this special issue, it focuses on the second question and identifies climate entrepreneurship in two subnational governments—the states of California (USA) and São Paulo (Brazil). Examining internal action, as well as interaction with local authorities, national governments and the international regime, entrepreneurial activities are identified in the invention, diffusion and evaluation of subnational climate policy in each case. The article draws from the recent scholarship on policy innovation, entrepreneurship and climate governance. It contributes to the literature by exploring entrepreneurial subnational government activity in addressing climate change and expanding the understanding of the effects of policy innovation at the subnational level.

  相似文献   
275.
The Oak Ridge Reservation, established in 1942, was the designated site for the construction of the atomic bomb. During a 20-year period from 1944 to 1963 radioactive and toxic chemical pollutants, especially mercury compounds were released into the surrounding waterways. Tree diversity and mycorrhizal presence and abundance were analyzed in the mercury-contaminated floodplains of East Fork Poplar Creek Oak Ridge (EFPC) (Tennessee). A subsequent greenhouse study was conducted to assess the phytotoxic effects of different mercuric solutions on Platanus occidentalis (American Sycamore), inoculated with soils from EFPC. Total soil mercury in the field had no effect on tree diversity. Organic species of mercury proved to be more toxic than inorganic species of mercury and soil inoculants from EFPC had no protective effects against Hg toxicity in our greenhouse study. Comparison of the effects of mercury contamination in our field and greenhouse studies was difficult due to uncontrolled factors.  相似文献   
276.
Environmental Science and Pollution Research - A novel hybrid nanomaterial, nanoscale zero-valent iron (nZVI)-grafted imogolite nanotubes (Imo), was synthesized via a fast and straightforward...  相似文献   
277.
Environmental Science and Pollution Research - Mercury and selenium concentrations and Se:Hg molar ratio in edible muscle and hepatopancreas of the crab Callinectes arcuatus from coastal lagoons of...  相似文献   
278.
A perfluorooctane sulfonic acid (PFOS) assessment was conducted on gibel carp (Carassius auratus gibelio), carp (Cyprinus carpio), and eel (Anguilla anguilla) in Flanders (Belgium). The liver PFOS concentrations in fish from the Ieperlee canal (Boezinge, 250-9031 ng/g wet weight, respectively) and the Blokkersdijk pond (Antwerp, 633-1822 ng/g wet weight) were higher than at the Zuun basin (Sint-Pieters-Leeuw, 11.2-162 ng/g wet weight) and among the highest in feral fish worldwide. Eel from the Oude Maas pond (Dilsen-Stokkem) and Watersportbaan basin (Ghent) had PFOS concentrations ranging between 212 and 857 ng/g wet weight. The hepatic PFOS concentration was significantly and positively related with the serum alanine aminotransferase activity, and negatively with the serum protein content in eel and carp. The hepatic PFOS concentration in carp correlated significantly and negatively with the serum electrolyte concentrations whereas a significant positive relation was found with the hematocrit in eel. Although 13 organochlorine pesticides, 22 polychlorinated biphenyl (PCB) congeners and 7 polybrominated diphenyl ethers (PBDEs) were also measured in the liver tissue, only PCB 28, PCB 74, gamma-hexachlorocyclohexane (gamma-HCH) and hexachlorobenzene (HCB) were suggested to contribute to the observed serological alterations in eel.  相似文献   
279.
280.
Thresholds to sexual maturity—either age or size—are critical life history parameters. Usually investigated in short-lived organisms, these thresholds and interactions among age, size, and growth are poorly known for long-lived species. A 34-year study of captive green turtles (Chelonia mydas) that followed individuals from hatching to beyond maturity provided an opportunity to evaluate these parameters in a long-lived species with late maturity. Age and size at maturity are best predicted by linear growth rate and mass growth rate, respectively. At maturity, resource allocation shifts from growth to reproductive output, regardless of nutrient availability or size at maturity. Although captive turtles reach maturity at younger ages than wild turtles, the extensive variation in captive turtles under similar conditions provides important insights into the variation that would exist in wild populations experiencing stochastic conditions. Variation in age/size at maturity should be incorporated into population models for conservation and management planning.  相似文献   
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