全文获取类型
收费全文 | 4546篇 |
免费 | 34篇 |
国内免费 | 13篇 |
专业分类
安全科学 | 63篇 |
废物处理 | 288篇 |
环保管理 | 266篇 |
综合类 | 737篇 |
基础理论 | 935篇 |
环境理论 | 4篇 |
污染及防治 | 1570篇 |
评价与监测 | 464篇 |
社会与环境 | 258篇 |
灾害及防治 | 8篇 |
出版年
2023年 | 47篇 |
2022年 | 143篇 |
2021年 | 138篇 |
2020年 | 53篇 |
2019年 | 65篇 |
2018年 | 169篇 |
2017年 | 127篇 |
2016年 | 230篇 |
2015年 | 120篇 |
2014年 | 262篇 |
2013年 | 461篇 |
2012年 | 277篇 |
2011年 | 277篇 |
2010年 | 215篇 |
2009年 | 166篇 |
2008年 | 239篇 |
2007年 | 250篇 |
2006年 | 226篇 |
2005年 | 153篇 |
2004年 | 124篇 |
2003年 | 110篇 |
2002年 | 95篇 |
2001年 | 59篇 |
2000年 | 48篇 |
1999年 | 35篇 |
1998年 | 16篇 |
1997年 | 14篇 |
1996年 | 11篇 |
1995年 | 26篇 |
1994年 | 18篇 |
1993年 | 15篇 |
1991年 | 8篇 |
1990年 | 11篇 |
1989年 | 9篇 |
1987年 | 8篇 |
1982年 | 10篇 |
1970年 | 12篇 |
1967年 | 10篇 |
1966年 | 12篇 |
1965年 | 18篇 |
1964年 | 28篇 |
1963年 | 13篇 |
1962年 | 17篇 |
1961年 | 14篇 |
1960年 | 15篇 |
1959年 | 32篇 |
1958年 | 36篇 |
1957年 | 21篇 |
1956年 | 20篇 |
1955年 | 19篇 |
排序方式: 共有4593条查询结果,搜索用时 15 毫秒
931.
Layered double hydroxides (LDHs) or hydrotalcite (HT)-like compounds with different kinds of metal ions (Mg-Al and Mg-Fe) in the brucite-like sheets were prepared and their adsorption properties were studied in the boron removal from aqueous solution under laboratory conditions. The hydrotalcites were synthesized by the coprecipitation method and were characterized by chemical analyses, X-ray diffraction (XRD), Fourier Transform infrared spectroscopy (FTIR) and specific surface area measurements (BET). The affinity of these materials with a mixture of B(OH)(3) and B(OH)(4)(-) was studied as a function of contact time, initial pH of the solutions, HT quantity and B concentration (adsorption isotherms). It was found that 120 min is enough time for the equilibrium state to be reached in boron adsorption. Boron removal was independent of the initial pH of the solutions because of the high buffering capacity of the LDHs. On the other hand, the adsorption capacity increases with increasing the adsorbent quantity. The adsorption isotherms, described by the Langmuir model, are of L-type, suggesting that B(OH)(4)(-) is adsorbed preferentially on HT-like materials. Besides, Mg-Al hydrotalcites showed higher adsorption capacity than Mg-Fe. We proposed that in Mg-Al hydrotalcites, the boron removal occurs by both adsorption on external surface and ion exchange, whereas for Mg-Fe it occurs only by surface adsorption. After treatment of a solution containing 5.2 mgBl(-1) with Mg-Al hydrotalcites the final boron concentration reached the recommended limit by WHO for drinking water (0.5 mgl(-1)). 相似文献
932.
Resource limitation of bacterial production distorts the temperature dependence of oceanic carbon cycling 总被引:2,自引:0,他引:2
Our view of the effects of temperature on bacterial carbon fluxes in the ocean has been confounded by the interplay of resource availability. Using an extensive compilation of cell-specific bacterial respiration (BRi) and production (BPi), we show that both physiological rates respond to changing temperature in a similar manner and follow the predictions of the metabolic theory of ecology. Their apparently different temperature dependence under warm, oligotrophic conditions is due to strong resource limitation of BP, but not of BRi. Thus, and despite previous preconception, bacterial growth efficiency (BGE = BPi/[BPi + BRi]) is not directly regulated by temperature, but by the availability of substrates for growth. We develop simple equations that can be used for the estimation of bacterial community metabolism from temperature, chlorophyll concentration, and bacterial abundance. Since bacteria are the greatest living planktonic biomass, our results challenge current understanding of how warming and shifts in ecosystem trophic state will modify oceanic carbon cycle feedbacks to climate change. 相似文献
933.
Health risk assessment maps for arsenic groundwater content: application of national geochemical databases 总被引:3,自引:0,他引:3
This investigation assesses the feasibility of calculating and visualizing health risk estimates from exposure to groundwater
contaminated with arsenic (As) using data from national geochemical databases. The potential health risk associated with As-contaminated
groundwater was assessed based on an elaboration of existing geochemical data in accordance with accepted methodological procedures
established for human health risk assessment (U.S. Environmental Protection Agency methodology). A screening analysis approach
was used for estimating the contribution of As to the total chronic health risk from exposure to groundwater contaminated
with potentially toxic elements, including As, Ba, Cd, Cu, Hg, Pb, Sb, Se and Zn, and the results indicate that As contributes
significantly (>50%) to this total health chronic risk in about 10% of Slovak territory. Based on the calculation of the
potential risk level by exposure modelling, increased chronic as well as carcinogenic risk levels (medium to high) were documented
in approximately 0.2 and 11% of the total Slovak area, respectively. The areas characterized by high health risk levels are
mainly those geogenically contaminated. High and very high carcinogenic risk was determined in 34 of 79 districts and in 528
of 2924 municipalities. 相似文献
934.
Benyei Petra Cohen Marianne Gresillon Etienne Angles Stéphane Araque-Jiménez Eduardo Alonso-Roldán María Espadas-Tormo Isidro 《Regional Environmental Change》2018,18(2):595-605
Regional Environmental Change - In the context of climate change, concern is raising about the negative effects of some pruning waste management practices. On the one hand, burning of pruning... 相似文献
935.
Marmett Bruna Carvalho Roseana Böek Dorneles Gilson Pires da Silva Igor Martins Romão Pedro Roosevelt Torres Nunes Ramiro Barcos Rhoden Cláudia Ramos 《Environmental science and pollution research international》2020,27(31):39019-39028
Environmental Science and Pollution Research - Obesity and physical inactivity threaten human health, and both could be solved with exercise. However, a higher amount of pollutants is inhaled... 相似文献
936.
Despite much discussion about the utility of remote sensing for effective conservation, the inclusion of these technologies in species recovery plans remains largely anecdotal. We developed a modeling approach for the integration of local, spatially measured ecosystem functional dynamics into a species distribution modeling (SDM) framework in which other ecologically relevant factors are modeled separately at broad scales. To illustrate the approach, we incorporated intraseasonal water-vegetation dynamics into a cross-scale SDM for the Common Snipe (Gallinago gallinago), which is highly dependent on water and vegetation dynamics. The Common Snipe is an Iberian grassland waterbird characteristic of European agricultural meadows and a member of one of the most threatened bird guilds. The intraseasonal dynamics of water content of vegetation were measured using the standard deviation of the normalized difference water index time series computed from bimonthly images of the Sentinel-2 satellite. The recovery plan for the Common Snipe in Galicia (northwestern Iberian Peninsula) provided an opportunity to apply our modeling framework. Model accuracy in predicting the species’ distribution at a regional scale (resulting from integration of downscaled climate projections with regional habitat–topographic suitability models) was very high (area under the curve [AUC] of 0.981 and Boyce's index of 0.971). Local water-vegetation dynamic models, based exclusively on Sentinel-2 imagery, were good predictors (AUC of 0.849 and Boyce's index of 0.976). The predictive power improved (AUC of 0.92 and Boyce's index of 0.98) when local model predictions were restricted to areas identified by the continental and regional models as priorities for conservation. Our models also performed well (AUC of 0.90 and Boyce's index of 0.93) when projected to updated water-vegetation conditions. Our modeling framework enabled incorporation of key ecosystem processes closely related to water and carbon cycles while accounting for other factors ecologically relevant to endangered grassland waterbirds across different scales, allowed identification of priority areas for conservation, and provided an opportunity for cost-effective recovery planning by monitoring management effectiveness from space. 相似文献
937.
938.
Holubová Šmejkalová Adéla Zíková Naděžda Ždímal Vladimír Plachá Helena Bitter Miroslav 《Environmental science and pollution research international》2021,28(11):13352-13364
Environmental Science and Pollution Research - Highly time-resolved particle number size distributions (PNSDs) were evaluated during 5 years (2013–2017) at four background stations in the... 相似文献
939.
Fernandes Francine Faia Moura Bárbara Baesso 《Environmental science and pollution research international》2021,28(31):41726-41735
Environmental Science and Pollution Research - The present study evaluates the development of visible injury related to phytotoxic ozone dose (PODy) in native tropical species Astronium graveolens... 相似文献
940.
Girón-Navarro Rocío Linares-Hernández Ivonne Teutli-Sequeira Elia Alejandra Martínez-Miranda Verónica Santoyo-Tepole Fortunata 《Environmental science and pollution research international》2021,28(21):26325-26358
Environmental Science and Pollution Research - Organochlorine pesticides have generated public concern worldwide because of their toxicity to human health and the environment, even at low... 相似文献