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581.
The chemical characteristics, element contents, mineral compositions, and the ameliorative effects on acid soils of five biomass ashes from different materials were analyzed. The chemical properties of the ashes varied depending on the source biomass material. An increase in the concrete shuttering contents in the biomass materials led to higher alkalinity, and higher Ca and Mg levels in biomass ashes, which made them particularly good at ameliorating effects on soil acidity. However, heavy metal contents, such as Cr, Cu, and Zn in the ashes, were relatively high. The incorporation of all ashes increased soil pH, exchangeable base cations, and available phosphorus, but decreased soil exchangeable acidity. The application of the ashes from biomass materials with a high concrete shuttering content increased the soil available heavy metal contents. Therefore, the biomass ashes from wood and crop residues with low concrete contents were the better acid soil amendments.  相似文献   
582.
TiO_2 in anatase crystal phase is a very effective catalyst in the photocatalytic oxidation of organic compounds in water. To improve its photocatalytic activity, the Ti-coating Mg Al hydrotalcite(Ti–Mg Al–LDH) was prepared by chemical vapor deposition(CVD) method.Response surface method(RSM) was employed to evaluate the effect of Ti species coating parameters on the photocatalytic activity, which was found to be affected by the furnace temperature, N2 flow rate and influx time of precursor gas. Application of RSM successfully increased the photocatalytic efficiency of the Ti–Mg Al–LDH in methylene blue photodegradation under UV irradiation, leading to improved economy of the process.According to the results from X-ray diffraction, scanning electron microscopy, Brunner–Emmet–Teller and Barrett–Joyner–Hallender, thermogravimetric and differential thermal analysis, UV–vis diffuse reflectance spectra analyses, the Ti species(TiO_2or/and Ti~(4+)) were successfully coated on the Mg Al–LDH matrix. The Ti species on the surface of the Ti–Mg Al–LDH lead to a higher photocatalytic performance than commercial TiO_2-P25. The results suggested that CVD method provided a new approach for the industrial preparation of Ti-coating Mg Al–LDH material with good photocatalytic performances.  相似文献   
583.
Taiwan Strait is a special channel for subtropical East Asian Monsoon and its western coast is an important economic zone in China. In this study, a suburban site in the city of Xiamen on the western coast of Taiwan Strait was selected for fine aerosol study to improve the understanding of air pollution sources in this region. An Aerodyne high-resolution time-of-flight aerosol mass spectrometer(HR-To F-AMS) and an Aethalometer were deployed to measure fine aerosol composition with a time resolution of 5 min from May 1to 18, 2015. The average mass concentration of PM1 was 46.2 ± 26.3 μg/m~3 for the entire campaign. Organics(28.3%), sulfate(24.9%), and nitrate(20.6%) were the major components in the fine particles, followed by ammonium, black carbon(BC), and chloride. Evolution of nitrate concentration and size distribution indicated that local NOx emissions played a key role in high fine particle pollution in Xiamen. In addition, organic nitrate was found to account for 9.0%–13.8% of the total measured nitrate. Positive Matrix Factorization(PMF)conducted with high-resolution organic mass spectra dataset differentiated the organic aerosol into three components, including a hydrocarbon-like organic aerosol(HOA) and two oxygenated organic aerosols(SV-OOA and LV-OOA), which on average accounted for 27.6%,28.8%, and 43.6% of the total organic mass, respectively. The relationship between the mass concentration of submicron particle species and wind further confirmed that all major fine particle species were influenced by both strong local emissions in the southeastern area of Xiamen and regional transport through the Taiwan Strait.  相似文献   
584.
This paper introduces the new approach of risk analysis established by the French Ministry of the Environment and develops the benefits of applying nuclear probabilistic safety assessment approaches to the chemical industry.In the aftermath of the AZF disaster in Toulouse on 21 September 2001, a new law was proposed by the French government asking for the investigation of all representative scenarios and the assessment of the probability of the resulting dangerous phenomena to demonstrate an acceptable level of safety. Therefore, any accident is investigated from a global point of view, according to its gravity and its probability.In 2000, the French Ministry of the Environment asked the Institute for Radiological Protection and Nuclear Safety (IRSN), and in particular its Systems and Risk Protection Assessment (SESPRI) and its Industrial Risks, Fire and Containment Assessment and Study (SERIC) departments, to conduct a Probabilistic Safety Assessment (PSA) study of an LPG distribution facility, specially for the BLEVE scenario. This study has showed the power of PSA for defining and prioritizing actions to be carried out to improve safety of facilities; however, it requires credible data for reliability and failure of the equipment, not available in generic failure databases.Since 2007, IRSN has taken several initiatives in collaboration with operators in order to provide more precise and representative failure rates for main safety equipment, ready to use in future PSA relative to LPG plants.  相似文献   
585.
化工园区整体安全性评价模式研究   总被引:1,自引:0,他引:1  
叶明珠 《四川环境》2011,30(1):61-66
本文旨在通过对化学工业园区安全性的研究,探求建立一种适合于化学工业园区定性安全评价的模式,重点通过对化学工业园区内企业间的安全相关性的研究使园区在规划、建设阶段达到整体最佳。并在此基础上提出了主要针对园区布局的安全评价方法。  相似文献   
586.
基于象限法和灰色关联法的水灾灾情等级评估   总被引:2,自引:1,他引:1  
水灾严重威胁着人类的财产与生活,水灾灾情等级的合理评估可以为防灾、减灾以及备灾工作提供科学的依据。通过改进象限法的临界指标,并用灰色关联法进行约束,提出基于象限法和灰色关联法的灾情等级评估方法。首先应用象限法对中国(除港、澳、台地区)的水灾灾情按省进行分级,再应用灰色关联法计算出代表各地区灾情大小的关联度,最后用各省的关联度对象限法的分级结果进行微调,得到中国一些地区水灾灾情等级评估的最终结果。结果表明:湖北、湖南、安徽为大灾地区;四川等19个地区为中灾地区;甘肃、海南、青海和新疆为小灾地区;北京、上海、天津、宁夏、西藏为微灾地区。  相似文献   
587.
农业领域作业者的听力防护问题极少被关注,以农机噪声、养殖场噪声及其对作业者伤害调查数据看,农业噪声对作业者的危害不容忽视,给予作业特点和需求,需要选择合适的听力保护装备,并建立听力保护计划,保护在噪声环境中工作的农业作业者。  相似文献   
588.
在时花椒风味物质的研究中,采用传统的有机溶剂萃取,并通过GC-MS对提取物进行了定性,实验结果表明,花椒中的香味物质主要有棕榈酸、芳樟醇、胡椒酮.  相似文献   
589.
文章选择清洁环保的钻井液处理剂进行抗高温钻井液体系实验研究与评价,对包被增粘剂、降失水剂等进行优选,对抗高温环保钻井液配方进行评价,研究出无毒、无害,抗温能力强、流变性好,失水较低的钻井液体系,现场应用满足高温深井的钻井生产要求。  相似文献   
590.
在实验室条件下模拟某液化天然气(liquefied natural gas,简称LNG)工程冷排水中余氯排放,并通过毒理实验研究海洋中余氯对大黄鱼(Larimichthys crocea)仔鱼和幼鱼的毒理效应.结果表明:在余氯浓度为0.14和0.20 mg·L-1时,仔鱼出现死亡现象,其他3个低浓度条件下仔鱼无死亡率;...  相似文献   
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