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11.
The frequently discussed gap between conservation science and practice is manifest in the gap between spatial conservation prioritization plans and their implementation. We analyzed the research‐implementation gap of one zoning case by comparing results of a spatial prioritization analysis aimed at avoiding ecological impact of peat mining in a regional zoning process with the final zoning plan. We examined the relatively complex planning process to determine the gaps among research, zoning, and decision making. We quantified the ecological costs of the differing trade‐offs between ecological and socioeconomic factors included in the different zoning suggestions by comparing the landscape‐level loss of ecological features (species occurrences, habitat area, etc.) between the different solutions for spatial allocation of peat mining. We also discussed with the scientists and planners the reasons for differing zoning suggestions. The implemented plan differed from the scientists suggestion in that its focus was individual ecological features rather than all the ecological features for which there were data; planners and decision makers considered effects of peat mining on areas not included in the prioritization analysis; zoning was not truly seen as a resource‐allocation process and not emphasized in general minimizing ecological losses while satisfying economic needs (peat‐mining potential); and decision makers based their prioritization of sites on site‐level information showing high ecological value and on single legislative factors instead of finding a cost‐effective landscape‐level solution. We believe that if the zoning and decision‐making processes are very complex, then the usefulness of science‐based prioritization tools is likely to be reduced. Nevertheless, we found that high‐end tools were useful in clearly exposing trade‐offs between conservation and resource utilization.  相似文献   
12.
太阳辐射试验标准中的太阳光谱分布   总被引:1,自引:0,他引:1       下载免费PDF全文
目的为太阳辐射试验标准、光老化试验标准修订时正确选择太阳光谱提供依据。方法辨析CIE NO.20,CIE NO.85两种出版物太阳辐射光谱特点,从五个方面对此问题进行探讨,统计这两种太阳辐射光谱带宽辐照度的误差;分析相对空气质量、臭氧与水分、云层光学厚度、地表反射率等因素对太阳辐射光谱辐照度的影响;分析人工辐射光源光谱分布特点,以及它们与太阳辐射光谱的差别;分析当前光老化试验标准对光谱辐照度允差的要求;介绍光老化试验结果间的可比性。结果 CIE NO.85光谱更准确、更细致,但其波长范围较窄,两种光谱辐照度的差别很小,大气环境中许多因素会降低到达地面的光谱辐照度;人工辐射光源光谱与太阳光谱的误差、光老化试验标准中光谱辐照度允差都远大于前述太阳辐射光谱间的误差,标准对太阳光谱波长范围的要求比CIE NO.85光谱宽。结论太阳辐射试验标准、光老化试验标准修订时,仍可选用CIE NO.20光谱作为太阳辐射光谱。  相似文献   
13.
This study investigates the equilibrium phase partitioning behavior of ethanol, isopropanol, and methanol in a two-phase liquid-liquid system consisting of water and an individual BTEX (Benzene, Toluene, Ethylbenzene, and Xylenes) compound. A previously developed computer program is enhanced to generate ternary phase diagrams for analysis of each three-component cosolvent-nonaqueous phase liquid (NAPL)-water mixture combination. The required activity coefficients are estimated using the UNIFAC (Universal Quasichemical Functional group Activity Coefficient) model. The UNIFAC-derived ternary phase diagrams generally show good agreement against published experimental data, and similar phase partitioning behavior is observed for every BTEX compound in the presence of the same cosolvent. Furthermore, a set of laboratory experiments is conducted to determine the maximum single-phase water content for every mixture combination considered in this study where the volume composition of the cosolvent and the NAPL components is a blend of 85% alcohol and 15% BTEX compound. Comparison of experimentally-derived maximum single-phase water contents against UNIFAC-derived results shows good agreement for mixtures containing ethanol and methanol, but relatively poor agreement for mixtures containing isopropanol.  相似文献   
14.
A method employing solid phase extraction followed by gas chromatography-mass spectrometry with negative chemical ionization has been developed for determination of ultratrace concentrations of perfluoroalkyl carboxylic acids in river water. The effects of the experimental parameters, such as the pH, additions of NaCl and an ion-pairing agent (tetraethylammonium bromide) and the kind of the elution agent, on the efficiency of the test acid extraction have been studied. The analyte extraction recoveries and the limits of detection and determination have been found. The method developed has been tested on determinations of perfluoroalkyl carboxylic acids in the waters of the two largest Czech rivers, Vltava and Labe (Elbe). The best extraction results have been attained without any alteration of the sample pH, with an addition of tetrabutylammonium bromide (a concentration of 50 μg mL−1 in the sample) and using methanol as the elution agent. Under these conditions, the recoveries of the test acids in the spiked real samples are within ranges from 60% to 104% and 53% to 111% for analyte concentration levels of 1.40 ng mL−1 and 0.14 ng mL−1, respectively, depending on the lengths of the perfluorinated chains of the acids. In general, the recovery decreases with increasing length of this chain. The method developed exhibits very low limits of detection and determination and the results are fully comparable with those obtained when using more expensive HPLC-MS/MS instrumentation. Typical values amount to tenths to tens of pg mL−1 and units to one hundred pg mL−1 for the limits of detection and determination, respectively; the measuring sensitivity increases with increasing length of the analyte chain. The analyzes of real samples from the Vltava and Elbe rivers have demonstrated that the results obtained are similar to the values published for contamination of the Elbe and other rivers in western and central Europe. The concentrations determined are of the order of units to tens of pg mL−1 and the C8-C10 acids occur most often.  相似文献   
15.
Atmospheric 85Kr concentration at Fukuoka, Japan was determined by an improved 85Kr analytical method using liquid scintillation counting (LSC). An average value of 1.54 ± 0.05 Bq m−3 was observed in 2008, which is about two times that measured in 1981 at Fukuoka, indicating a 29 mBq y−1 rate of increase as an average for these 27 years. The analytical method developed involves collecting Kr from air using activated charcoal at liquid N2 temperature and purifying it using He at dry ice temperature, followed by Kr separation by gas chromatography. An overall Kr recovery of 76.4 ± 8.1% was achieved when Kr was analyzed in 500-1000 l of air. The Kr isolated by gas chromatography was collected on silica gel in a quartz glass vial cooled to liquid N2 temperature and the activity of 85Kr was measured with a low-background LS counter. The detection limit of 85Kr activity by the present analytical method is 0.0015 Bq at a 95% confidence level, including all propagation errors, which is equivalent with 85Kr in 1.3 l of the present air under the analytical conditions of 72.1% counting efficiency, 0.1597 cps background count rate, and 76.4% Kr recovery.  相似文献   
16.
采用动态热分析仪对TDE-85环氧/碳纤维复合材料进行测试,并在探索试验基础上,开展了一系列温度的热老化试验,选择弯曲强度作为TDE-85环氧/碳纤维材料的贮存寿命评定指标,通过对热老化试验后样品弯曲强度数据的统计分析,预测了其贮存寿命。  相似文献   
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