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941.
HSE审核是客观了解企业HSE管理现状,审查企业HSE业绩的一种行之有效的监督管理方法,目前国内外许多大型石油石化公司普遍采用该方法对企业的HSE管理绩效进行考察.中国石化集团公司于2006年6月发布了,并于6月至7月间开展HSE管理体系审核. 相似文献
942.
活性危害的评估由理论筛选,热稳定性的实验筛选,动力学参数的检测装置,紧急排放系统的设计、筛选和放大,过程设计和优化等几个部分组成. 相似文献
943.
In this study, CO2 was bubbled into Fe0-contained solution to create an acidic environment favorable to reduction of aqueous nitrate under various water qualities. Results showed that nitrate of 30 mg l(-1) could be removed from solutions almost completely within 30 min under the conditions of 2 g Fe0 l(-1) and CO2 bubbling flow rate of 200 ml min(-1). It was observed from the Fe0/CO2 system that one mole of nitrate reduced by Fe0 led to the formation of 6.6 mol of ferrous ions. The removal of nitrate increases with increasing Fe0 dosage, however, the removal makes no difference as the Fe0 is applied at a relatively higher dosage. In the system with various water qualities, nitrate removal was inhibited significantly in the presence of humic acid. Calcium ions strongly retard nitrate removal, whereas chloride ions promote the reduction of nitrate in a significant way. Sodium ions impose only slight inhibitive effect on nitrate removal. Water molecule in the studied system can be of significance due to its competitive capability of electrons released from Fe0. 相似文献
944.
Removal of SO2 from O2-containing flue gas by activated carbon fiber (ACF) impregnated with NH3 总被引:1,自引:0,他引:1
Adsorption of SO(2) from the O(2)-containing flue gas by granular activated carbons (GACs) and activated carbon fibers (ACFs) impregnated with NH(3) was studied in this technical note. Experimental results showed that the ACFs were high-quality adsorbents due to their unique textural properties. In the presence of moisture, the desulphurization efficiency for the ACFs was improved significantly due to the formation of sulfuric acid. After NH(3) impregnation of ACF samples, nitrogen-containing functional groups (pyridyl C(5)H(4)N- and pyrrolyl C(4)H(4)N-) were detected on the sample surface by using an X-ray photoelectron spectrometer. These functional groups accounted for the enhanced SO(2) adsorption via chemisorption and/or catalytic oxidization. 相似文献
945.
Environmental contamination of heavy metals from zinc smelting areas in Hezhang County, western Guizhou, China 总被引:14,自引:0,他引:14
Total heavy metal (Cd, Cr, Cu, Pb and Zn) concentrations were evaluated in smelting waste, soil, crop and moss samples collected from the Hezhang artisanal zinc smelting areas, Guizhou, China. Soil samples from the cornfield near the smelting sites contained extremely high Cd (5.8-74 mg kg(-1)), Pb (60-14,000 mg kg(-1)) and Zn (260-16,000 mg kg(-1)) concentrations. Elevated heavy metal concentrations were also found in corn plants and total Pb (0.80-1.5 mg kg(-1)) and Cd (0.05-0.76 mg kg(-1)) concentrations in corn grain have totally or partially exceeded the national guidance limits for foodstuff. Thus, the soil-to-crop transfer of heavy metals might pose a potential health risk to the local residents. Similar to the high heavy metal levels in soil and corn, Cd, Cr, Cu, Pb and Zn concentrations in moss samples collected from the smelting sites ranged from 10 to 110, 10 to 55, 26 to 51, 400 to 1200 and 330 to 1100 mg kg(-1), respectively, exhibiting a local spatial pattern of metals deposition from the atmosphere. Based on examination of Zn/Cd and Pb/Cd ratios of the analyzed samples, we have distinguished between the flue gas dust derived and smelting waste derived metals in different environmental compartments. 相似文献
946.
中国“三农问题”的体制转型 总被引:3,自引:0,他引:3
孙津 《中国人口.资源与环境》2008,18(4)
建设社会主义新农村要求一系列的制度创制,这些要求表明,一直以来全社会关注的“三农问题”进入了一个体制转型的新阶段。文章阐述了这个阶段所必然要产生的一些主要制度创制内容,即:在责任制基础上的新型土地生产关系创制;针对粮食经济转型构建发展现代农业的制度基础;建立与生存、生产和生活统一性关系相适应的农村民生统筹制度体系;从城乡统筹的角度促进乡村治理和制度创新。根据转型的目标设计,农民作为这个转型的主体其“自身就是问题”的性质将随着转型的实施和实现失去意义,而农村和农业即使存在问题,也只是主体需要并可台解决的对象性工作,所以“三农问题”将在中国整体的现代化发展中失去意义。 相似文献
947.
Jin Y. Fan Jin J. Geng Hong Q. Ren Xiao R. Wang Chao Han 《Journal of environmental science and health. Part. B》2013,48(10):844-850
Roundup® is a glyphosate-based herbicide containing a mixture of surfactants. This paper evaluates the toxic effects of Roundup® and its main constituents on the goldfish, Carassius auratus, after 7 days exposure. Fish were exposed to 0.16, 0.032 and 0.0064 mg/L of Roundup® [containing 41% isopropylamine salt of glyphosate (G.I.S) and 18% polyoxyethylene amine (POEA)], G.I.S, and POEA. Their livers were taken for determining reactive oxygen species (ROS), superoxide dismutase (SOD) activity, malondialdehye (MDA) content and acetylcholinesterase (AChE) activity. Hydroxyl radical (·OH) could be induced by exposing Roundup® at a rate of 43%–111%, G.I.S at 90%–124% and POEA at142%–157%. A decreased SOD activity was observed in fish exposed to G.I.S and POEA. The contents of MDA significantly increased when exposed to Roundup® at all concentrations, 0.16 mg/L G.I.S and 0.032 mg/L POEA. The exposure led to an inhibition of AChE in livers overall during the experimental periods. POEA was more toxic than Roundup® or G.I.S during this experiment. AChE and ·OH are supposed to be sensitive biomarkers of the exposure of Roundup® and its main constituents to C. auratus. 相似文献
948.
安全文化是随着社会的繁荣、城乡的发展及科技进步,从工业文明、社会文化衍生而来。本文从国内外事故灾害频发的特点出发,探讨国内提出安全防灾文化建设的概念,并着重分析了拓展安全防灾文化建设的大思路。 相似文献
949.
地质灾害管理信息系统 总被引:7,自引:1,他引:6
在地质灾害普查、勘查、防治、社会经济状况、统计信息等资料的基础上,设计出为决策提供服务的地质灾害管理信息系统,以便对地质灾害进行科学管理 相似文献
950.
Yuliang Zhou Dong Zhang Ping Zhou Zhaoli Wang Pan Yang Juliang Jin Yi Cui Shaowei Ning 《Journal of the American Water Resources Association》2023,59(3):571-583
In univariate frequency analysis, the return period of an event has a one-to-one correspondence with its characteristic value, and the response of the hydraulic structure to hydrological load expressed by the hydrological event is monotonic. Thus, the design criteria of the hydraulic structure can be equivalently represented by the return period of the hydrological event, and consequently, design event-based design parameters evaluated have been widely used in practical engineering. However, the monotonic correspondence between the return period of the hydrological event and the response of the hydraulic structure does not exist in the multivariate context, and hydrological load with a larger joint return period does not always produce a more unsafe response. Misunderstandings of concepts of return periods of hydrological event, and estimation of hydrological design events usually take place in multivariate frequency analysis. This study theoretically derives the relations between different types of joint return periods, joint return period and its marginal return periods, the occurrence of bivariate extreme events and their return periods, and then the theoretical framework is tested. Results from the case contribute to the understanding of bivariate return periods of hydrological event, and the results demonstrate that design criteria cannot be equivalently represented by joint return periods of hydrological load, and design parameters of the hydraulic structure should not be determined by multivariate hydrological design events. 相似文献