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811.
Outbound offending: The journey to crime and crime sprees 总被引:1,自引:0,他引:1
Studies on crime and mobility primarily focus on local crime patterns. The city has long played an important role, whether analysing the offence or the offender. This paper goes beyond city boundaries and discusses ‘outbound offenders’, whose crime trips start in a city, but end outside. It is argued that a substantial proportion of crime trips follow this pattern, indicating that areas other than cities also provide interesting opportunities for property crime. We link outbound offending to a number of features that may explain crime travelling, including the target’s features and offender/offence features. We find that outbound offending mostly occurs towards affluent target regions and near motorways, as such confirming findings from previous research. We also find crime sprees to be indicative for mobile offending. Thus, mobile property offenders tend to compensate for travelled distances, not only by targeting affluent areas and using fast transportation means, but also by committing several successive offences, hereby reducing their relative transportation cost for each offence. 相似文献
812.
813.
Ana F. L. Godoi Eliza Y. Sawada Mary Rosa R. de Marchi René Van Grieken Ricardo H. M. Godoi 《Water, Air, & Soil Pollution: Focus》2009,9(3-4):163-169
The use of inks containing organic solvents by the offset printing process implies in the release of volatile organic compounds to the work environment. Many of these compounds such as benzene, toluene, ethylbenzene, and the xylene isomers (well known by the acronym BTEX) are extremely toxic. In this study, the BTEX concentrations were determined in two different printing plants that use distinct types of inks: the conventional and the so-called ecological, which is manufactured based on vegetal oil. Concentration ranges were 43–84, 15–3,480, 2–133, 5–459, and 2–236 μg m?3 for benzene, toluene, ethylbenzene, m?+?p-xylene, and o-xylene, respectively, for the conventional printing plant. At the ecological printing plant, concentration ranges were below limit of detection (<LD)-31, <LD-618, <LD-1,690, <LD-10,500, <LD-3,360 μg m?3 for benzene, toluene, ethylbenzene, m?+?p-xylene, and o-xylene, respectively. BTEX concentrations are lower at the ecological printing environment than in the conventional, where mineral oil-based inks are used. However, the worker who cleans the printing matrices is exposed to high concentrations of ethylbenzene and xylenes, due probably to the cleaning product’s composition (containing high amounts of BTEX). Although the BTEX concentrations found in both printing work environments were below the limits considered by the Brazilian Law for Activities and Unhealthy Operations (NR-15), the exposure to such vapors characterizes risk to the workers’ health for some of the evaluated samples, mainly the personal ones. 相似文献
814.
KARINE PAYET MATHIEU ROUGET KAREN J. ESLER BELINDA Reyers TONY REBELO MARK W. THOMPSON JAN H. J. VLOK 《Conservation biology》2013,27(3):531-541
Extinction‐risk assessments aim to identify biological diversity features threatened with extinction. Although largely developed at the species level, these assessments have recently been applied at the ecosystem level. In South Africa, national legislation provides for the listing and protection of threatened ecosystems. We assessed how land‐cover mapping and the detail of ecosystem classification affected the results of risk assessments that were based on extent of habitat loss. We tested 3 ecosystem classifications and 4 land‐cover data sets of the Little Karoo region, South Africa. Degraded land (in particular, overgrazed areas) was successfully mapped in just one of the land‐cover data sets. From <3% to 25% of the Little Karoo was classified as threatened, depending on the land‐cover data set and ecosystem classification applied. The full suite of threatened ecosystems on a fine‐scale map was never completely represented within the spatial boundaries of a coarse‐scale map of threatened ecosystems. Our assessments highlight the importance of land‐degradation mapping for the listing of threatened ecosystems. On the basis of our results, we recommend that when budgets are constrained priority be given to generating more‐detailed land‐cover data sets rather than more‐detailed ecosystem classifications for the assessment of threatened ecosystems. El Efecto de la Cobertura Terrestre y el Mapeo de Ecosistemas en la Valoración de Riesgos en los Ecosistemas en Little Karoo, Sudáfrica 相似文献
815.
Lynne Van Herwerden J. Howard Choat Stephen J. Newman Matthieu Leray Grethe Hillersøy 《Marine Biology》2009,156(8):1595-1607
Here the population genetic structure of an ecologically and economically important coral reef fish, the coral trout Plectropomus leopardus, is investigated in the context of contemporary and historical events. Coral trout were sampled from four regions (six locations)
and partial mtDNA D-loop sequences identified six populations (Fst = 0.89209, P < 0.0001): Scott Reef and the Abrolhos Islands in west Australia; the Great Barrier Reef (GBR), represented by northern and
southern GBR samples; New Caledonia and Taiwan, with Taiwan containing two genetic lineages. Furthermore, this study identified
source and sink populations within and among regions. Specifically, the northern population in west Australia (Scott Reef)
was identified, as the source for replenishment of the Abrolhos population, whilst New Caledonia was a source for recruitment
to the GBR. Based on these insights from a single mtDNA marker, this study will facilitate the development of rational management
plans for the conservation of P. leopardus populations and therefore mitigate the risk of population declines from anthropogenic influences. 相似文献
816.
Katleen Van Meel Benjamin Horemans Agnieszka Krata László Bencs Anna Jolanta Buczyñska Alin C. Dirtu Anna Worobiec René Van Grieken 《Environmental Chemistry Letters》2010,8(2):157-163
Marine aerosols have extensively been monitored in the framework of a research project to investigate the inorganic and organic
nutrient fluxes of the atmospheric nitrogen input into the North Sea. As a part of this project bulk analysis was also performed
by energy dispersive X-ray fluorescence (EDXRF) on a total of 366 samples in order to provide detailed elemental composition.
Samples have been clustered per campaign and differences were related to backward trajectories. Elements as Cl, Si, and S
appeared to be the best tracers for coastal aerosols. Therefore they have been chosen to represent each campaign and to map
the seasonal variations. It is clear that Cl is an excellent tracer for oceanic trajectories, while a less clear correlation
between the soil dust components and the air mass trajectories is found. 相似文献
817.
818.
Francisco Alvarez-Cuadrado Ngo Van Long 《Journal of Environmental Economics and Management》2009,58(2):154-168
This paper proposes a welfare criterion that balances the need for development and the concern for the least advantaged generations, and explores its implications. This criterion, called the mixed Bentham–Rawls criterion, moderates the effect of discounting, yet permits some degree of intertemporal trade-off. It is a weighted average of two terms: (a) the sum of discounted utilities and (b) the utility level of the least advantaged generation. We derive necessary conditions to characterize growth paths that satisfy our criterion, and show that in some models with familiar dynamic specifications, an optimal path exists and displays appealing characteristics. 相似文献
819.
KARIN PERHANS CLAES KINDSTRAND MATTIAS BOMAN LINE BOBERG DJUPSTRÖM LENA GUSTAFSSON LEIF MATTSSON LEIF MARTIN SCHROEDER JAN WESLIEN SOFIE WIKBERG 《Conservation biology》2008,22(5):1331-1339
Abstract: Including both economic costs and biological benefits of sites in systematic reserve selection greatly increases cost‐efficiency. Nevertheless, limited funding generally forces conservation planners to choose which data to focus the most resources on; therefore, the relative importance of different types of data must be carefully assessed. We investigated the relative importance of including information about costs and benefits for 3 different commonly used conservation goals: 2 in which biological benefits were measured per site (species number and conservation value scores) and 1 in which benefits were measured on the basis of site complementarity (total species number in the reserve network). For each goal, we used site‐selection models with data on benefits only, costs only, and benefits and costs together, and we compared the efficiency of each model. Costs were more important to include than benefits for the goals in which benefits were measured per site. By contrast, for the complementarity‐based goal, benefits were more important to include. To understand this pattern, we compared the variability in benefits and in costs for each goal. By comparing the best and the worst possible selection of sites with regard to costs alone and benefits alone for each conservation goal, we introduced a simple and consistent variability measure that is applicable to all kinds of reserve‐selection situations. In our study, benefit variability depended strongly on how the conservation goal was formulated and was largest for the complementarity‐based conservation goal. We argue that from a cost‐efficiency point of view, most resources should be spent on collecting the most variable type of data for the conservation goal at hand. 相似文献
820.
M. Yu. Semenov T. V. Khodzher V. A. Obolkin V. M. Domysheva L. P. Golobokova N. A. Kobeleva O. G. Netsvetaeva V. L. Potemkin R. Van Grieken N. Fukuzaki 《Chemistry and Ecology》2006,22(1):1-11
Data from 3-year-long observations on the chemical composition of precipitation, atmospheric gases, aerosols, soils, and surface waters at three monitoring stations in the Baikal region are presented. The stability of terrestrial ecosystems and surface waters to acidification has been estimated quantitatively. It has been shown that, unlike soils, surface waters of the Baikal watershed are more sensitive to acid deposition. The permissible acidity load for soils and surface waters of the territory varied from 0.30 to 20.00 keq ha-1 yr-1, whereas the maximal contemporary acidity load attains 0.50 keq ha-1 yr-1. 相似文献