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761.
陕北能源化工基地建立生态工业园模式选择及两种模式构建流程 总被引:1,自引:1,他引:0
生态工业园的建设主要有4种模式。通过比较各个模式的特点,针对陕北能源化工基地现状,提出基地建立生态工业园应选择改造重构与产业共生两种模式:绘制流程图,对两种模式的构建流程进行研究。 相似文献
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764.
Kay Grossmann Thuro Arnold Robin Steudtner Stefan Weiss Gert Bernhard 《Die Naturwissenschaften》2009,96(8):963-974
Low-temperature alteration reactions on uranium phases may lead to the mobilization of uranium and thereby poses a potential
threat to humans living close to uranium-contaminated sites. In this study, the surface alteration of uraninite (UO2) and uranium tetrachloride (UCl4) in air atmosphere was studied by confocal laser scanning microscopy (CLSM) and laser-induced fluorescence spectroscopy using
an excitation wavelength of 408 nm. It was found that within minutes the oxidation state on the surface of the uraninite and
the uranium tetrachloride changed. During the surface alteration process U(IV) atoms on the uraninite and uranium tetrachloride
surface became stepwise oxidized by a one-electron step at first to U(V) and then further to U(VI). These observed changes
in the oxidation states of the uraninite surface were microscopically visualized and spectroscopically identified on the basis
of their fluorescence emission signal. A fluorescence signal in the wavelength range of 415–475 nm was indicative for metastable
uranium(V), and a fluorescence signal in the range of 480–560 nm was identified as uranium(VI). In addition, the oxidation
process of tetravalent uranium in aqueous solution at pH 0.3 was visualized by CLSM and U(V) was fluorescence spectroscopically
identified. The combination of microscopy and fluorescence spectroscopy provided a very convincing visualization of the brief
presence of U(V) as a metastable reaction intermediate and of the simultaneous coexistence of the three states U(IV), U(V),
and U(VI). These results have a significant importance for fundamental uranium redox chemistry and should contribute to a
better understanding of the geochemical behavior of uranium in nature.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
765.
A case study for water using network of a Starch industry in the state of Gujarat, India, is undertaken with an aim to reduce demineralised water and freshwater flow rates and consequently the wastewater flow rate. The problem was identified as a multi contaminant, reuse and recycle problem. The freshwater consumption and demineralised water consumption were 100 t/h and 51 t/h respectively before modification and the network was dealing with three major contaminants such as total organic content, total dissolved solids and total suspended solids. A program was developed in MATLAB for analysis using Water Pinch. The improved water using network designed for the present work consumed less demineralised and freshwater. The reductions are of the tune of 28% and 64.38% for demineralised and fresh water respectively. Due to alteration in piping, there will be a saving of 406 026 INR per year, which will be utilized for development of efficient environment policy for the company. The entire concept had been implemented on plant level on 1st February-2009 and the reductions are of the tune of 25% and 60% for demineralised and fresh water respectively. 相似文献
766.
ICP-OES法测定大气和废气颗粒物中的金属元素 总被引:1,自引:0,他引:1
将微波消解法与电感耦合等离子体发射光谱法(ICP-OES)相结合,对大气和废气颗粒物中金属元素的微波消解条件及ICP-OES测定条件进行了优化研究,建立了大气和废气颗粒物中铝(Al)、钡(Ba)、镉(Cd)、铬(Cr)、铜(Cu)、锰(Mn)、钼(Mo)、镍(Ni)、铅(Pb)、锡(Sn)、锶(Sr)及锌(Zn)等金属元素的测定方法。对方法的检出限进行了测定,各元素的检出限均低于0.04 mg/L;对方法的精密度进行了测定,各元素的相对标准偏差在2.59%~7.14%之间;对方法的准确度进行了测定,质控滤膜中各元素的回收率在89.6%~119%之间,颗粒物参考物质中各元素的回收率在85.1%~107%之间,并将该方法成功应用到 TSP、污染源废气实际样品中金属元素的测定。 相似文献
767.
Marta HervaAuthor VitaeAmaya FrancoAuthor Vitae Eugenio F. CarrascoAuthor VitaeEnrique RocaAuthor Vitae 《Journal of Cleaner Production》2011,19(15):1687-1699
This paper reviews a series of environmental indicators developed in the last years that were found suitable to be applied at corporate level for the evaluation of production processes and products. The indicators reviewed in this paper were classified into four main groups: 1) Indicators of Energy and Material Flows; 2) Indicators with a Territorial Dimension; 3) Indicators of Life-Cycle Assessment; 4) Indicators of Environmental Risk Assessment. Integrative and single index indicators such as the ecological footprint or carbon footprint were found as the most appealing for enterprises, although there is a need to advance in the field to combine the simplicity required at corporate level for tracking and reporting environmental data, and the scientific rigor and transparency necessary to make the scores reliable. Hence, for each of the indicators revised it was stated what they do and do not measure so that misleading information was not used for decision making at corporate level. 相似文献
768.
769.
采用微波无极灯强化光催化对直接耐酸大红4BS的降解进行研究。初步考察反应温度、微波功率、pH值、催化剂TiO2浓度、曝气量、直接耐酸大红4BS初始浓度、外加氧化剂H2O2量等因素对直接耐酸大红4BS降解效果的影响。实验结果表明,反应最佳温度是55℃、最佳催化剂TiO2投加量为6 g/L;较低pH值、高微波功率、外加氧化剂H2O2有利于直接耐酸大红4BS的降解。与常规的光催化相比,微波减弱pH值和染料初始浓度对降解效率的影响。在优化工艺参数和未加H2O2条件下,反应4 h后,质量浓度为500 mg/L的直接耐酸大红4BS降解率达到90%。 相似文献
770.
Xiaoyu Liu Bing Zhu Wenji Zhou Shanying Hu Dingjiang Chen Charla Griffy-Brown 《International Journal of Greenhouse Gas Control》2011,5(5):1240-1249
China's calcium carbide output has dominated the global market for several years, driven by the demand for PVC (polyvinyl chloride), a fundamental polymer material and also the primary downstream product of calcium carbide in China. The fast growth of this energy-intensive industry leads to an inevitable increase in CO2 emissions. However, there is a large reduction potential with process improvement in this industry which is currently characterized by widespread outdated facilities. In this study, we attempt to assess the reduction potential of CO2 emissions in China's calcium carbide production, based on the analysis of CO2 emission patterns and estimation of the emission amount. Three scenarios regarding process improvement are employed to conduct this assessment. The results imply that the cumulative CO2 abatement in the Current Policy Scenario and in the Strengthened Policy Scenario from 2008 to 2020, compared with the Baseline Scenario, are 89.0 and 107.6 million t, respectively. The specific measures and policy implications to achieve this potential are also discussed in the article. 相似文献