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441.
高吉峰 《安全.健康和环境》2008,8(11)
2007年7月17日9时左右,位于美国堪萨斯州山谷中心的巴顿溶剂公司的威奇托工厂发生了爆炸和火灾事故。11名当地居民和1名消防队员接受了医学治疗。这次事故导致大约6000名山谷中心居民的撤离,摧毁了1个储罐区域并且极大地影响了巴顿溶剂公司的经营业务。 相似文献
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Liquan Zhang Zhanguo Gao Richard Armitage Martin Kent 《Frontiers of Environmental Science & Engineering in China》2008,2(2):187-197
The spectral reflectance of recently formed salt marshes at the mouth of the Yangtze River, which are undergoing invasion
by Spartina alterniflora, were assessed to determine the potential utility of remotely sensed data in assessing future invasion and changes in species
composition. Following a review of published research on remote sensing of salt marshes, 53 locations along three transects
were sampled for paired data on plant species composition and spectral reflectance using a FieldSpec™ Pro JR Field Portable
Spectroradiometer. Spectral data were processed concerning reflectance, and the averaged reflectance values for each sample
were reanalysed to correspond to a 12-waveband bandset of the Compact Airborne Spectral Imager. The spectral data were summarised
using principal components analysis (PCA) and the relationships between the vegetation composition, and the PCA axes of spectral
data were examined. The first PCA axis of the reflectance data showed a strong correlation with variability in near infrared
reflectance and ‘brightness’, while the second axis was correlated with visible reflectance and ‘greenness’. Total vegetation
cover, vegetation height, and mudflat cover were all significantly related to the first axis. The implications of this in
terms of the ability of remote sensing to distinguish the various salt marsh species and in particular the invasive species
S. alterniflora were discussed. Major differences in species with various physiognomies could be recognised but problems occurred in separating
early colonising S. alterniflora from other species at that stage. Further work using multi-seasonal hyperspectral data might assist in solving these problems. 相似文献
445.
Gao J Liu L Liu X Lu J Zhou H Huang S Wang Z Spear PA 《Environment international》2008,34(8):1097-1103
Persistent organochlorine pesticides pollutants (OCPs) have been reported to occur at relatively high concentrations in some Chinese waters. In order to map the distribution of organochlorine pesticides in the surface water throughout China, samples were collected from over 600 sites in seven major river basins and three main internal rivers drainage areas during 2003 and 2004. The surface water samples were analyzed for the representative organochlorine pesticides contaminants including lindane (gamma-HCH), p,p'-DDT and heptachlor epoxide. In general, the most frequently detected compound was lindane, being detected in 83.9% of samples (mean=31.3 ng/l; range <0.17-860 ng/l), and the highest concentration was present in the Yellow River basin. p,p'-DDT was detected in 63.1% of the samples collected (mean=14.6 ng/l; range <0.14-368 ng/l) with the highest concentration present in the Huaihe River basin. Heptachlor epoxide was detected in only 9.3% of water samples (range <0.11-10 ng/l). Measured concentrations for the three compounds were low and rarely exceed the environment quality standard for surface water of China. Lindane was more frequently detected at much higher concentrations in the rivers of northern China compared with those of southern China. The sites with higher concentration of lindane and p,p'-DDT mainly occurred in the Yellow River and Huaihe River basins, so the results of this investigation indicate that the organochlorine pesticide contamination of Yellow River and Huaihe River basins should be of particular concern relative to the other basins. When compared with other regions of the world, it appears that the Chinese surface water is moderately polluted by lindane and p,p'-DDT. 相似文献
446.
Hong Wang Jay Gao Li-Liang Ren Yan Kong He Li Ling Li 《Regional Environmental Change》2013,13(1):115-123
As wildlife habitat is in constant evolution, periodic monitoring is essential to assess its quality. In this study, the change to the red-crowned crane habitat in the Yellow River Delta Nature Reserve was detected from multi-temporal remote sensing data from 1992 to 2008 in a geographic information system. Habitat fragmentation was derived from both physical constraints and human disturbance. The changing habitat quality was assessed against five landscape indices. The results obtained from Landsat TM images indicate that potential habitat shrank 37.9 % during 1992–2001, but recovered 99.4 % by 2008. Suitable habitat shrank by 4,329 ha to a level below that of 1992 despite an increase of 4,747 ha in potential habitat due to an increase of 9,075 ha in fragmented areas. Both landscape indices and the red-crowned crane population reveal that suitable habitat was the most fragmented in 2001, but the least fragmented in 1992. Therefore, it is inadequate to just restore wetland through artificial diversion of channel flow to the Reserve to preserve the crane habitat. Commensurate efforts should also be directed at improving habitat quality by minimizing human activities and spatially juxtaposing water and reed marshes harmoniously inside the Reserve. 相似文献
447.
Abstract China has won the name of the world factory being famous for exporting a great deal of and various kinds of low-price merchandise. However, most of Chinese exports are primary goods or manufactured products that create heavy pollution and require intensive use of resources. Chinese products go abroad, but their following harms stay behind. The article analyzes many obvious low-price facts in China and their concomitant terrible environmental results in detail, and points out that there are huge hidden troubles in the way of China's sustainable development behind her seemingly flourishing economy. 相似文献
448.
Research on Tourism Competitiveness of Chinese Island Counties: Based on Factor and Cluster Analysis
Abstract From the perspective of tourism competitiveness, the paper takes 12 island counties of China as the research object, and applies the method of factor analysis to study their competitiveness. The result shows that Putuo and Dinghai are more competitive while Pingtan and Nan’ao are less competitive. Finally, the 12 island counties are divided into four styles: first-class competitive county (Putuo), seond-class competitive counties (Dinghai,Yuhuan), third-class competitive counties (Chongming, Daishan, Changdao, Changhai and Shengsi), fourth-class competitive counties (Dongshan, Dongtou, Pingtan and Nan’ao) by cluster analysis. The classification of island counties is to clear their relative position, then to promote their development. 相似文献
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Soybean [ (L.) Merr.] stalk-based carbons were prepared by phosphoric acid activation at different carbonization temperatures. Characteristics of the prepared carbon, including specific surface area, iodine number, and amount of methylene blue sorption, were determined. Experiments on phenanthrene, naphthalene, and acenaphthene, as representatives of polycyclic aromatic hydrocarbons (PAHs), removal from aqueous solution by the prepared carbon were conducted at different levels of carbon addition. The results indicated that the specific surface area, iodine number, and amount of methylene blue sorption increased with an increase of carbonization temperature. The maximum values were observed at 700°C and were 287.63 m g, 508.99 mg g, and 90.14 mg g, respectively. The removal efficiencies of phenanthrene, naphthalene, and acenaphthene tended to increase with increasing carbon amounts and carbonization temperature. The optimal removal performance was obtained under the experimental conditions of carbon concentrations of 0.04 g 32 mL and carbonization temperature of 700°C, and the removal efficiencies of phenanthrene, naphthalene, and acenaphthene were 99.89, 100, and 95.64%, respectively. The performance of the prepared carbon was superior to that of commercial activated carbon. Additionally, for the same carbon concentrations, the removal efficiency of PAHs on prepared carbons followed the order: phenanthrene > naphthalene > acenaphthene. Results obtained from this work provide some insight into the reuse of an agricultural residue, and also provide a new application for the treatment of PAHs in contaminated water utilizing activated carbon prepared from agricultural residues. 相似文献