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951.
根据某石化分公司HF中毒死亡事故,编制了氢氟酸烷基化装置检修过程HF泄漏中毒事故故障树对故障树分析中的最小割集、最小径集分析及结构重要度进行了分析,得出加强对岗位人员的安全教育,强化作业人员对岗位风险的认识是预防事故发生的主要措施.  相似文献   
952.
"十一五"期间,中国实现了单位GDP能耗下降19.1%、节能6.3亿吨标准煤、减少二氧化碳排放15亿吨的目标责任,但面临的资源、环境约束形势依然严峻,交通运输行业作为重要的高污染高能耗领域有着不可推卸的责任。目前,交通部门在新能源的利用中存在的核心技术缺乏,自主创新能力不足,相关的配套政策、设施不到位等问题,也依然制约着中国交通运输行业的绿色发展。当前中国交通部门存在着严重的资源、环境问题,需借鉴国外发展绿色交通的经验,并结合本国国情,着力促进交通运输行业的节能减排,实现经济社会的可持续发展。  相似文献   
953.
采用滴定吸附法将过氧乙酸组装于中孔硅胶中,通过红外光谱分析和N2吸附法对组装体进行了表征,研究了常温常压下,该组装体氧化、吸附、脱除柴油硫化物的活性.结果表明,该组装体具有优良的脱硫性能.柴油中硫化物与过氧乙酸在硅胶孔中发生氧化反应,氧化产物被吸附在硅胶上,使柴油的含硫量从1697μg/g降到14μg/g,符合美国环境保护署标准.  相似文献   
954.
以草酸铁络合物/H2O2作光氧化剂,利用日光对垃圾渗滤生化出水进行了光氧化降解试验。结果表明,在溶液的初始体系pH=3.0,H2O2投加量为460mg/L,Fe3+质量浓度为20mg/L条件下,反应60min后,CODCr去除率可达80%以上;溶液初始体系的pH、H2O2和Fe3+的投加量及废水的水质对光解过程有显著影响,而且在太阳光照射下,CODCr去除率比紫外光照射下高。研究表明,在一定试验条件下,用日光/H2O2/草酸铁体系对城市垃圾渗滤液处理效果较好,可作为垃圾渗滤液的深度处理。  相似文献   
955.
水体pH和曝气方式对藻类生长的影响   总被引:9,自引:0,他引:9  
利用水族箱微宇宙研究了藻类在不同pH和曝气条件下的生长和种类变化.使用天然湖水,一组试验每天调节pH,使其分别保持在8.0、8.5、9.0和9.5;另一组试验是设定不同的曝气方式,分别为不曝气、完全曝气、昼间曝气和夜间曝气,定期测定水体叶绿素a和藻类组成.pH试验结果显示,在pH 8.0~9.5范围内,pH 8.5下藻类生长状况最好,pH 9.5下生长最差,人为改变pH使其远离8.5能够抑制藻类生长.曝气试验结果显示,曝气不能抑制水体中藻类的生长,昼间曝气甚至还有明显的促进作用.  相似文献   
956.
The objective of the following research is to theoretically quantify the enhancement of interphase mass transfer of dissolved non-aqueous phase liquid (NAPL) compounds from the non-aqueous phase to the aqueous phase and the enhancement of dispersive mass transport from a NAPL zone due to destruction of dissolved NAPL compounds. For relatively slow reaction rates, such as for permanganate and perchloroethene (PCE), local-scale mass transfer enhancement is expected to be small. Dispersive mass transport with reaction from a horizontal NAPL zone can be quantified using equations derived for a mathematically equivalent falling film reactor system. In contrast to local-scale interphase mass transfer, dispersive mass transport from NAPL zones may be significantly increased by reaction. Enhancement factors due to destruction of the NAPL compound(s) are mainly dependent on NAPL solubility and oxidant concentration and to a lesser extent on reaction rate, stoichiometry, and transverse dispersion coefficients. Higher NAPL solubility and/or lower oxidant concentration reduces the maximum expected enhancement factor. Reaction enhancement factors for mass transport from NAPL zones are expected to be in the range of 5-50 for permanganate and chlorinated solvents. Theoretical results suggest that assuming instantaneous reaction rates may be appropriate for dispersive mass transport from NAPL zones.  相似文献   
957.
Widespread use of the rare earth elements (REEs) in China for agricultural purposes, together with many other applications, has resulted in a remarkable increase of REE concentrations in the environment. The comparative bioaccumulations of representative light, medium and heavy REEs in a variety of tissues of carp (Cyprinus carpio L.) were investigated for an evaluation of their impacts on aquatic animals. The fish were exposed continuously to solutions containing 0.50 mg litre(-1) of each element for 45 days at pH 6.0 and sacrificed at time intervals. Skeleton, muscle, gills and internal organs were analysed for REE contents. A method using cation-exchange resin separation and ICP-AES determination was developed for the quatification of individual REEs. The results show that carp has low ability to take up the REEs under the experimental conditions. The order of REEs under the experimental conditions. The order of maximum bioconcentration factors was mostly internal organs > gills > skeleton > muscle. Neither synergistic nor antagonistic effects of the mixed REE solutions for carp were observed. The relative distributions of different REEs in the investigated tissues exhibited similar patterns. Among the selected tissues studied, the concentration of a heavy REE (Y) was the smallest, while concentrations of a medium (Gd) and a light REE (La) showed only a slight difference.  相似文献   
958.
Mesoporous Co_3 O_4(meso-Co_3 O_4)-supported Pt(0.53 wt.% Pt/meso-Co304) was synthesized via the KIT-6-templating and polyvinyl alcohol(PVA)-assisted reduction routes.Mesoporous CoO(meso-CoO) was fabricated through in situ reduction of meso-Co304 with glycerol,and the 0.18-0.69 wt.% Pt/meso-CoO samples were generated by the PVA-assisted reduction method.Meso-Co_3 O_4 and meso-CoO were of cubic crystal structure and the Pt nanoparticles(NPs) with a uniform size of ca.2 nm were well distributed on the mesoCo_3 O_4 or meso-CoO surface.The 0.56 wt% Pt/meso-CoO(0.56 Pt/meso-CoO) sample performed the best in benzene combustion(T_(50%)=156℃and T_(90%)=186℃at a space velocity of 80,000 mL/(g h)).Introducing water vapor or C02 with a certain concentration led to partial deactivation of 0.56 Pt/meso-CoO and such a deactivation was reversible.We think that the superior catalytic activity of 0.56 Pt/meso-CoO was intimately related to its good oxygen activation and benzene adsorption ability.  相似文献   
959.
Pollen pollution and allergy are becoming prominent issues in China. However, few studies on pollinosis have been reported. As an allergen in the atmosphere, allergenic Humulus scandens pollen was collected from four districts of Shanghai, including Wusong (WS), Jiading (JD), Xujiahui (XJH) and Songjiang (SJ). The mass concentrations of SO2, NO2, O3, PM10, and PM2.5 (particulate matter with air dynamic diameter less than 10 and 2.5 µm, respectively) near the four sampling sites were also recorded during Humulus scandens pollen season. The allergenicity of the Humulus scandens pollen was assessed by using of a rat model and enzyme linked immunosorbent assay (ELISA). Relationships between the allergenicity and air pollutants were correlated. Our results demonstrated that the biological viability of the pollens collected from the four districts exhibited no significant differences. ELISA and dot blotting results further demonstrated that the serum of sensitized rats exhibited much higher immune-reactive response than that of control groups. Western blotting showed that the 15 KD (1KD = 1000 dalton) proteins of Humulus pollen led to the allergic response. The allergenic intensity of Humulus pollen protein from different samples followed the pattern: WS > JD > XJ > SJ. There was a negative relationship between the allergenicity of Humulus pollens and PM10 (R = -0.99) / PM2.5 (R = -0.73), and a positive relationship with O3 (R = 0.92). These data clearly showed that PM10 and PM2.5 could enhance Humulus pollen protein release, and O3 could aggravate the allergenicity of the Humulus pollen.  相似文献   
960.
地下污油罐是石油炼化行业中的常用储罐,分析了地下土壤或油罐内部介质等因素对其造成的腐蚀,结合实际案例提出了污油罐防腐措施  相似文献   
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