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361.
化工行业危险废物调查方法的建立与应用研究 总被引:2,自引:0,他引:2
在化工行业危险废物调查实践基础上,建立了适用于化工行业危险废物调查的快速浏览法.该法通过对化工企业工业流程的每一工序的物料投入与产出分析,得到产品整个生产工艺的物料平衡图,据此可分析物料转化率、危险废物产生环节、产生量、产废系数等.介绍了该方法的建立过程、主要调查步骤及其在化学农药厂的实际应用案例. 相似文献
362.
通过对板料拉深法兰变形区和直壁传力区的应力分析 ,应用功平衡法 ,推导了极限拉深系数与摩擦系数之间的关系式 ,并讨论了摩擦对拉深性能的影响。 相似文献
363.
364.
自然资源资产负债表编制中生态损益核算 总被引:4,自引:2,他引:2
生态损益核算是自然资源资产负债表的重要部分,是对自然资源分类核算的扩展和补充。本文梳理生态损益核算的总体思路,系统总结生态损益核算技术,以围场县为例进行实证,遵循先实物后价值的核算原则,选择森林、草地、湿地生态系统,按不同的生态服务指标进行实物量和价值量的核算,并在已有的核算基础上计算各类型生态系统的实物量参数和价值量参数,以便根据面积统计数据进行快速简洁的核算比较。研究发现:围场县2015年生态系统服务功能价值量总值为338.99亿,与2013年相比增加了0.04%。生态系统服务功能价值量从大到小依次为草地、森林、湿地,核算期间森林和草地生态系统价值量分别下降0.06%和0.22%,湿地生态系统价值量增加4.47%。研究成果有助于全面理解和量化自然资源数量变化和质量变化带来的生态效应,并为自然资源资产负债表中的负债核算提供数据基础。 相似文献
365.
Gregory J. McCabe David M. Wolock 《Journal of the American Water Resources Association》2019,55(4):1053-1064
Model estimated monthly water balance (WB) components (i.e., potential evapotranspiration, actual evapotranspiration, and runoff [R]) for 848 United States (U.S.) Geological Survey 8‐digit hydrologic units located in the Mississippi River Basin (MRB) are used to examine the temporal and spatial variability of the MRB WB for water years 1901 through 2014. Results indicate the MRB can be divided into nine subregions with similar temporal variability in R. The WB analyses indicated ~79% of total water‐year MRB runoff is generated by four of the nine subregions and most of the R in the basin is derived from surplus (S) water during the months of December through May. Furthermore, the analyses showed temporal variability in S is largely controlled by the occurrence of negative atmospheric pressure anomalies over the western U.S. and positive atmospheric pressure anomalies over the eastern U.S. coast. This combination of atmospheric pressure anomalies results in an anomalous flow of moist air from the Gulf of Mexico into the MRB. In the context of paleo‐climate reconstructions of the Palmer Drought Severity Index, since about 1900 the MRB has experienced wetter conditions than were experienced during the previous 500 years. 相似文献
366.
文章分析了石油管道储运企业的生产工艺特点和技术特征,指出现有的制造业和第三产业的清洁生产审核方法及评价指标体系不能完全适用于石油管道储运企业.文章针对该类企业生产过程中能耗高和存在潜在风险等特点,探索并确定了以能耗平衡和物料平衡为核心、以风险评估为重点的清洁生产审核方法,并用于实际审核.文章为石油管道储运企业的节能、降耗、减排和风险防范提供了技术支持,也为该类企业的清洁生产审核提供了有效的借鉴. 相似文献
367.
Abstract The article puts forward the process and means of regional water and land balance research, and then from two scenarios which are the balances under natural regulation and human intervention, calculated and analysed the balance between water and land on Ningxia Plain. For the balance under natural regulation named farmland water balance, using farmland water resource balance equation, the research estimated the monthly farmland water balance of 8 major crops for all of the 12 counties on Ningxia Plain in the period of 1960–2001; for the balance under human intervention, the research estimated land-use water balance equation of the counties in 2000, and calculated the balance between land use and water resources including irrigating water of all the 12 counties on Ningxia Plain. Results showed that ①precipitation can not meet the water demand of the crops for growth and development on Ningxia Plain, and water shortage is the primary character of farmland water balance under natural regulation, ②the diversity of water and land balance of different counties is distinctly influenced by the crop structure, water quantity for irrigation and irrigation level. ③Irrigation water could meet the crop water demand on Ningxia Plain in 2000, but there was not much space to expand irrigating cultivated land. 相似文献
368.
B.A. Wrenn A. Virkus A.D. Venosa 《Environmental pollution (Barking, Essex : 1987)》2009,157(6):1807-1814
The effects of surfactant composition on the ability of chemical dispersants to disperse crude oil in fresh water were investigated. The objective of this research was to determine whether effective fresh water dispersants can be designed in case this technology is ever considered for use in fresh water environments. Previous studies on the chemical dispersion of crude oil in fresh water neither identified the dispersants that were investigated nor described the chemistry of the surfactants used. This information is necessary for developing a more fundamental understanding of chemical dispersion of crude oil at low salinity. Therefore, we evaluated the relationship between surfactant chemistry and dispersion effectiveness. We found that dispersants can be designed to drive an oil slick into the freshwater column with the same efficiency as in salt water as long as the hydrophilic-lipophilic balance is optimum. 相似文献
369.
Jiangwei WangSuqin Li Guohong Xiong Daqiang Cang 《Resources, Conservation and Recycling》2011,55(8):755-759
To improve the efficiency of water use and reuse, a digitalized water network system was implemented in a steel industrial complex. The system consisted of four parts: online instrument and sensing devices, programmable logic controller, data communication network and control center based on expert knowledge. The system achieved real-time monitoring, diagnosis, and early warning of cooling water system using data collected inline, and enabled data connectivity and transmission of self-developed software applications on personal computer. This research used a steel enterprise as a case study. After the analysis of its cooling water system and water-saving potential using water balance test, a digitalized water network was evaluated and implemented, and we believe this network can be suitable for steel industry in general. 相似文献
370.
The critical loads concept is used by the UN-ECEConvention on Long Range Transboundary Air Pollution(CLRTAP) for setting pollution reduction targets.Increasing numbers of countries are adopting the SimpleMass Balance equation (SMB) to calculate critical loads ofacidifying S and N for forest soils. The equation is madeup of a series of mass balances each of which is used tocalculate a leaching flux. The assumptions in the SMBequation were investigated by testing its ability topredict current sulphur load and by comparing each of thecalculated leaching fluxes to measured rates. It was notpossible to predict current sulphur load at our sites usingthe SMB equation. The leaching tests demonstrated that,primarily due to its steady state assumptions, the SMBequation generates critical loads that are theoretical longterm estimates of risk, and are untestable. Thesimplifying assumptions sometimes lead to illogicalresults. Some of these can be improved by adding a final,simple but dynamic, calculation step to determine theexpected time until effects are observed. Theacceptability of combining annual average data, which bestapproximates steady state, with a biological indicator isquestionable. It is not possible to test critical loadscalculated using the SMB equation when applied with all ofits assumptions but it is possible to test its fundamentalapproach using non steady state data. 相似文献