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21.
Austria produces about 700,000 tons of hazardous waste a year. Approximately 8% are sent to the incinerating facility EBS near Vienna. Approximately 60% THW (treated hazardous wastes) are finally disposed of. An unknown amount is sent to foreign countries for storage and landfilling. By order of the Ministry of Agriculture and the Ministry of Public Health our institute elaborates guidelines for designing and operating final disposal hazardous waste facilities. This paper deals with the fundamental aspects and the present state of these guidelines. 相似文献
22.
Jianfeng Zhang Guang-Cai Chen Shangjun Xing Qixiang Sun Qihua Shan Jinxing Zhou 《国际发展与全球生态学杂志》2013,20(6):475-480
The Yellow River Delta region in China is a land area of 1,200,000 ha with rich natural resources. Adverse environmental conditions, such as low rainfall and high salinity, promote the dominance of black locust trees for afforestation. With the increase of CO2 in the atmosphere, this forest and others throughout the world have become valued for their ability to sequester and store carbon. Forests store carbon in aboveground biomass (i.e. trees), belowground biomass (i.e. roots), soils and standing litter crop (i.e. forest floor and coarse woody debris). There are well-developed methods to sample forest ecosystems, including tree inventories that are used to quantify carbon in aboveground tree biomass. Such inventories are used to estimate the types of roundwood products removed from the forest during harvesting. Based on standard plot inventories and stem analyses, carbon sequestration estimates of trees were 222.41 t ha?1 for the Yellow River Delta region accounted for 67.12% of the whole forest. Similarly, carbon storage by herbaceous matter and soil was 0.50 and 50.34 t ha?1, respectively. The results suggest that carbon sequestration in the forest ecosystem was performed by most of the forest, which plays an increasingly important role in sequestering carbon as the stand grows. 相似文献
23.
Jessica M. Driscoll Lauren E. Hay Melanie K. Vanderhoof Roland J. Viger 《Journal of the American Water Resources Association》2020,56(1):16-29
This study explores the viability of using simulated monthly runoff as a proxy for landscape‐scale surface‐depression storage processes simulated by the United States Geological Survey’s National Hydrologic Model (NHM) infrastructure across the conterminous United States (CONUS). Two different temporal resolution model codes (daily and monthly) were run in the NHM with the same spatial discretization. Simulated values of daily surface‐depression storage (treated as a decimal fraction of maximum volume) as computed by the daily Precipitation‐Runoff Modeling System (NHM‐PRMS) and normalized runoff (0 to 1) as computed by the Monthly Water Balance Model (NHM‐MWBM) were aggregated to monthly and annual values for each hydrologic response unit (HRU) in the CONUS geospatial fabric (HRU; n = 109,951) and analyzed using Spearman’s rank correlation test. Correlations between simulated runoff and surface‐depression storage aggregated to monthly and annual values were compared to identify where which time scale had relatively higher correlation values across the CONUS. Results show Spearman’s rank values >0.75 (highly correlated) for the monthly time scale in 28,279 HRUs (53.35%) compared to the annual time scale in 41,655 HRUs (78.58%). The geographic distribution of HRUs with highly correlated monthly values show areas where surface‐depression storage features are known to be common (e.g., Prairie Pothole Region, Florida). 相似文献
24.
Surender Reddy Salkuti 《International Journal of Green Energy》2020,17(13):853-863
ABSTRACT This paper solves an optimal generation scheduling problem of hybrid power system considering the risk factor due to uncertain/intermittent nature of renewable energy resources (RERs) and electric vehicles (EVs). The hybrid power system considered in this work includes thermal generating units, RERs such as wind and solar photovoltaic (PV) units, battery energy storage systems (BESSs) and electric vehicles (EVs). Here, the two objective functions are formulated, i.e., minimization of operating cost and system risk, to develop an optimum scheduling strategy of hybrid power system. The objective of proposed approach is to minimize operating cost and system risk levels simultaneously. The operating cost minimization objective consists of costs due to thermal generators, wind farms, solar PV units, EVs, BESSs, and adjustment cost due to uncertainties in RERs and EVs. In this work, Conditional Value at Risk (CVaR) is considered as the risk index, and it is used to quantify the risk due to intermittent nature of RERs and EVs. The main contribution of this paper lies in its ability to determine the optimal generation schedules by optimizing operating cost and risk. These two objectives are solved by using a multiobjective-based nondominated sorting genetic algorithm-II (NSGA-II) algorithm, and it is used to develop a Pareto optimal front. A best-compromised solution is obtained by using fuzzy min-max approach. The proposed approach has been implemented on modified IEEE 30 bus and practical Indian 75 bus test systems. The obtained results show the best-compromised solution between operating cost and system risk level, and the suitability of CVaR for the management of risk associated with the uncertainties due to RERs and EVs. 相似文献
25.
Mowing is the main management of Hulun Buir grasslands in Inner Mongolia; therefore, understanding the changes of soil organic carbon (SOC), total nitrogen (TN), and carbon sequestration under different mowing frequencies will provide an important scientific basis for grassland carbon sink management in Inner Mongolia. Three treatment plots were devised in the study area, including enclosed sample (Y), mowing every other year (2G), and mowing once a year (1G), where SOC, TN content and storage were investigated. The results showed that with increased mowing frequency, the SOC and TN content showed a decreasing trend in the 0-30 cm depth soil layer. The SOC and TN content were different in each soil layer, which decreased gradually with increasing soil depth in Y and 2G plots, whereas increased gradually in 1G plots. The soil carbon storage was significantly correlated with the soil nitrogen storage, and both showed a significant linear decrease with increased mowing frequency, which showed as carbon and nitrogen loss. In 2G plots, the soil carbon storage decreased by 17.1% and soil nitrogen storage decreased by 20.8%. In 1G plots, the soil carbon storage decreased by 21.6% and soil nitrogen storage decreased by 29.3%. The results showed that the change of soil carbon and nitrogen was sensitive to mowing frequency for the Hulun Buir grassland. It is possible to reduce the loss of carbon and nitrogen by reasonably controlling mowing frequency, and the sustainable use of grassland could be achieved with appropriate fertilization. Keywords. © 2018 Science Press. All rights reserved. 相似文献
26.
结合心理学知识从人为因素的角度分析和归纳了油气储运设施事故的原因,提出了应对人为因素负面影响的措施和对策。 相似文献
27.
28.
Bottled water may not be safer, or healthier, than tap water. The present studies have proved that styrene and some other aromatic compounds leach continuously from polystyrene (PS) bottles used locally for packaging. Water sapmles in contact with PS were extracted by a preconcentration technique called as "purge and trap" and analysed by gas chromatograph-mass spectrometer (GC/MS). Eleven aromatic compounds were identified in these studies. Maximum concentration of styrene in PS bottles was 29.5 μg/L. Apart from styrene, ethyl benzene, toluene and benzene were also quantified but their concentrations were much less than WHO guide line values. All other compounds were in traces. Quality of plastic and storage time were the major factor in leaching of styrene. Concentration of styrene was increased to 69.53 μg/L after one-year storage. In Styrofoam and PS cups studies, hot water was found to be contaminated with styrene and other aromatic compounds. It was observed that temperature played a major role in the leaching of styrene monomer from Styrofoam cups. Paper cups were found to be safe for hot drinks. 相似文献
29.
研究了由潜水含水层、在海底延伸的承压含水层和介于其间的弱透水层构成的滨海含水层系统中,弱透水层的弹性储水以及含水层的海潮荷载效应对承压含水层中的地下水位的影响.研究结果表明,当海底弱透水层延伸足够长时,它的弹性储水对承压含水层中的海潮引起的水头波动有增强作用. 相似文献
30.
云南省土壤污染状况调查中样品的保存与管理 总被引:1,自引:0,他引:1
主要介绍了土壤污染状况调查中,应通过规范要求土壤样品的保存与管理步骤,确保土壤污染状况调查数据的准确性与可比性。 相似文献