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131.
Monitoring forest structure at landscape level: a case study of Scots pine forest in NE Turkey 总被引:1,自引:0,他引:1
This study aims to investigate the change in spatial-temporal configuration of secondary forest succession and generate measurements for monitoring the changes in structural plant diversity in Yaln?zçam Scots pine forest in NE Turkey from 1972 to 2005. The successional stages were mapped using the combination of Geographic Information System (GIS), Global Positioning System (GPS), aerial photos and high resolution satellite images (IKONOS). Forest structure and its relationship with structural plant diversity along with its changes over time were characterized using FRAGSTATS. In terms of spatial configuration of seral stages, the total number of fragments increased from 572 to 735, and mean size of patch (MPS) decreased from 154.97 ha to 120.60 ha over 33 years. The situation resulted in forestation serving appropriate conditions for plant diversity in the area. As an overall change in study area, there was a net increase of 1823.3 ha forest during the period with an average annual forestation rate of 55.25 ha year?1(0.4% per year). In conclusion, the study revealed that stand type maps of forest management plans in Turkey provide a great chance to monitor the changes in structural plant diversity over time. The study further contributes to the development of a framework for effective integration of biodiversity conservation into Multiple Use Forest Management (MUFM) plans using the successional stages as a critical mechanism. 相似文献
132.
In this study, aluminium (Al), lead (Pb), cadmium (Cd), selenium (Se) and arsenic (As) contents in milk and different dairy product samples were measured. Pb, Cd, As, Al and Se contents in the milk and different dairy products ranged from 0.054 mg/kg (milk powder)?1.100 mg/kg (Ka?ar cheese), 0.009 mg/kg (whey powder and yogurt)?1.051 mg/kg (Tulum cheese), 0.010 mg/kg (whey powder)?0.146 mg/kg (butter), 2.848 mg/kg (ice cream)?8.778 (drained yogurt) and n.d. (ice cream, milk and whey powder, yogurt, ayran and Lor cheese)?0.434 mg/kg (Tulum cheese), respectively. The 75% of White and Ka?ar cheeses, 50% of Lor and 12.5% of Tulum cheese samples contained higher Pb according to the legal limits established by the Turkish Food Codex and European Communities regulation and 12.5% of Tulum cheese sample contained Cd. It was concluded that Pb contents of milk and dairy products from this region might be highly hazardous to human 相似文献
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135.
Wastewater pollution in industrial areas is one of the most important environmental problems. Heavy metal pollution, especially
chromium pollution in wastewater sources from dyeing and tannery has affected the life on earth. This pollution can affect
all ecosystems and human health directly or by food chain. Therefore, the determination of chromium in this study is of great
importance. Dil Creek is located in the eastern Marmara region and discharges into the Izmit Gulf. This water source is used
for irrigation in agriculture and as drinking water for animals. In this study, a rapid, sensitive and selective method for
the speciative direct determination of Cr (III) and Cr (VI) in dyeing waste water samples collected from the nearest station
to Izmit Gulf of Dil Creek in May 2006 by inductively coupled plasma-atomic emission spectrometry (ICP-AES) has been developed.
An analysis of a given sample is completed in about 15 min for ICP-AES the method. As the result of the chromium analysis,
the limit of quantification (LOQ) for the Cr (III), Cr (VI) and total Cr were founded as 0.0111 ± 0.0002 mg/l (RSD, 1.80%),
0.0592 ± 0.0010 mg/l (RSD, 1.70%) and 0.0703 ± 0.0020 mg/l (RSD, 2.84%) respectively. In addition, the general mathematical
formula has been developed to calculate the concentration of Cr(III), which can be applied to any other metal species. The
result of Cr (VI) analysis indicated that water quality of Creek was IV. class quality according to the inland water classification.
In order to validate the applied method, recovery studies were performed. 相似文献
136.
In this study, Grey model (GM) and artificial neural network (ANN) were employed to predict suspended solids (SSeff) and chemical oxygen demand (CODeff) in the effluent from a wastewater treatment plant in industrial park of Taiwan. When constructing model or predicting, the influent quality or online monitoring parameters were adopted as the input variables. ANN was also adopted for comparison. The results indicated that the minimum MAPEs of 16.13 and 9.85% for SSeff and CODeff could be achieved using GMs when online monitoring parameters were taken as the input variables. Although a good fitness could be achieved using ANN, they required a large quantity of data. Contrarily, GM only required a small amount of data (at least four data) and the prediction results were even better than those of ANN. Therefore, GM could be applied successfully in predicting effluent when the information was not sufficient. The results also indicated that these simple online monitoring parameters could be applied on prediction of effluent quality well. 相似文献
137.
烤胶废料活性炭对含铬废水的处理能力 总被引:3,自引:0,他引:3
介绍了微波照射下氯化锌法制取烤胶废料活的方法,用该方法所制烤胶废料活性炭处理含废水的结果表明,烤胶废料活性炭具有吸附容量大,过滤速度快,操作控制方便等优点,活性炭对铬的吸附容量是市售一级粉末活性炭的1.8倍。 相似文献
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140.
Wet deposition and dry deposition samples were collected in an urban/industrialized area of Izmit Bay, North-eastern Marmara Sea, Turkey, from September 2002 to July 2003. The samples were analyzed for sixteen polycyclic aromatic hydrocarbon (PAH) compounds by using HPLC-UV technique. Wet and dry deposition concentrations and fluxes of PAHs were determined. The results showed that PAH concentrations were high because of industrial processes, heavy traffic and residential areas next to the sampling site. Total dry deposition flux of the fifteen 3-6 ring PAHs was 8.30 microg m(-2)day(-1), with a range of 0.034-1.77 microg m(-2)day(-1). The total wet deposition flux of the fifteen 3-6 ring PAHs was 1716 microg m(-2) 11 month(-1), with a range of 10-440 microg m(-2) 11 month(-1). Significant seasonal differences were observed in both types of deposition samples. The winter fluxes of total PAHs were 1.5 and 2.5 times greater than those of the warm period for wet and dry deposition samples, respectively. Factor analysis of dry deposition samples and back trajectory analysis of wet deposition samples were also used to characterize and identify the PAH emission sources in this study. 相似文献