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141.
从影响长输管道安全的外部因素、事故定义、事故分类以及事故数据分析和事故报告等几个方面,对国际上主要长输管道事故数据库进行了对比分析,提出了建立我国长输管道事故数据库的建议.  相似文献   
142.
The paper presents a novel cleaner process for metal recovery from the Printed Circuit Board (PCB) waste sludge by assistance of ultrasound. The process can effectively recover heavy metals at low cost with high separation and recovery efficiency, produce high quality products and also achieve zero waste discharge with operation at industrial scale. With the PCB waste sludge containing (wet content) 3.14–4.85% copper and 3.71–4.23% iron, copper recovery efficiency of 95.2–97.5% and iron recovery efficiency of 97.1–98.5% were achieved, while the purity of copper sulfate produced by the process was 98.0% and the produced ferric chloride had a satisfied quality for using as a coagulant material for the plant on-site wastewater treatment. The process had been successfully scaled up to the industrial scaled applications in a heavy metal recovery plant in city of Huizhou, China for more than two years. The novel cleaner heavy metal recovery process has a great prospect on the applications of resources recovery and environmental protection practices.  相似文献   
143.
长江三峡花岗岩地区土壤流失时间分布特性   总被引:5,自引:1,他引:4  
长江三峡花岗岩地区坡面土壤流失以耕地砂砾化面蚀和有部分植物覆盖坡面的鳞片状面蚀为主,该地土壤流失研究结果表明,由以上两类面蚀导致的土壤流失量月分布与月降雨量的分布基本趋势一致,二者呈现较为明显的线性相关关系。地面坡度>30°的裸地土壤流失量达5000t/km3·a以上,覆盖度≥0.70的林地土壤流失量<500t/km2·a,该流域土壤流失量为1544.14t/km2·a,产沙量为694.86t/km2·a  相似文献   
144.
本文以过氧化氢-甲基红,在活化剂α、α~1-联吡啶存在下,建立了催化光度法测定痕量铁(Ⅲ)的方法,其灵敏度为2.68×10~(-11)gFe(Ⅲ)/ml,线性范围为0~0.6μgFe(Ⅲ)/25ml。用于桂林风景点水中痕量铁测定,结果令人满意。  相似文献   
145.
重大工业危险源(罐区)监控预警系统   总被引:4,自引:2,他引:2  
系统建立了管理软件和硬件监控相结合的安全生产监控预警系统,在安全管理的基 础上,把罐区诸多的危险参数给予实时监测、报警和控制。本系统实现了生产过程控制与安全监控 相结合,安全监测报警与事故预案相结合,既满足了生产控制又实现了动态的安全管理,对安全生产 具有较大意义。  相似文献   
146.
Porous Cu-BTC material was synthesized by the solvothermal method. Powder X-ray diffraction (PXRD) was used to test the phase purity of the synthesized material and investigate its structural stability under the influence of flue gas components. The thermal stability of the material was determined through thermal gravimetric (TG) analysis. Scanning electron microscopy (SEM) was employed to study the microstructure of the material. Cu-BTC was demonstrated not only to have high CO2 adsorption capacity but also good selectivity of CO2 over N2 by means of packed bed tests. The adsorption capacity of Cu-BTC for CO2 was about 69 mL/g at 22°C. The influence of the main flue gas components on the CO2 capacity of the material were discussed as well.  相似文献   
147.
Zero valent iron (ZVI) is expected to help create an enhanced anaerobic environment that might improve the performance of anaerobic treatment. Based on this idea, a novel ZVI packed upflow anaerobic sludge blanket (ZVI-UASB) reactor was developed to treat azo dye wastewater with variable influent quality. The results showed that the reactor was less influenced by increases of Reactive Brilliant Red X-3B concentration from 50 to 1000 mg/L and chemical oxygen demand (COD) from 1000 to 7000 mg/L in the feed than a reference UASB reactor without the ZVI. The ZVI decreased oxidation-reduction potential in the reactor by about 80 mV. Iron ion dissolution from the ZVI could buffer acidity in the reactor, the amount of which was related to the COD concentration. Fluorescence in situ hybridization test showed the abundance of methanogens in the sludge of the ZVI-UASB reactor was significantly greater than that of the reference one. Denaturing gradient gel electrophoresis showed that the ZVI increased the diversity of microbial strains responsible for high efficiency.  相似文献   
148.
Oxidation of aniline by persulfate in aqueous solutions was investigated and the reaction kinetic rates under different temperature, persulfate concentration and pH conditions were examined in batch experiments. The results showed that, the aniline degradation followed pseudo first-order reaction model. Aniline degradation rate increased with increasing temperature or persulfate concentration. In the pH range of 3 to 11, a low aniline degradation rate was obtained at strong acid system (pH 3), while a high degradation rate was achieved at strong alkalinity (pH 11). Maximum aniline degradation occurred at pH 7 when the solution was in a weak level of acid and alkalinity (pH 5, 7 and 9). Produced intermediates during the oxidation process were identified using liquid chromatography-mass spectrometry technology. And nitrobenzene, 4-4’-diaminodiphenyl and 1-hydroxy-1,2-diphenylhydrazine have been identified as the major intermediates of aniline oxidation by persulfate and the degradation mechanism of aniline was also tentatively proposed.  相似文献   
149.
Nansi Lake is located on the east line of the South-to-North Water Diversion Project in China. A comprehensive study was carried out to investigate the spatial and temporal distribution of cyanobacteria in the lake from June 2008 to May 2011 based on monthly sample monitoring from five stations. The effect of environmental factors on cyanobacterial abundance was also evaluated. The cyanobacterial community contained 15 genera and 23 species. The cyanobacterial abundance of each monitoring station ranged from 0 to 1.53× 107 cells/L with an average of 1.45×106 cells/L, which accounted for 11.66% of the total phytoplankton abundance. The dominant species of cyanobacteria were Pseudanabaena (32.94%) and Merismopedia (19.85%), not the bloom-forming algae such as Microcystis and Anabaena. In addition, the cyanobacterial community structure and water quality variables changed substantially over the survey period. Redundancy analysis (RDA) suggested that temperature and phosphorus were important environmental factors that affected cyanobacteria. Temperature was the most important factor affecting cyanobacterial abundance. The effect of phosphorus on cyanobacterial abundance was more notable in warm periods than in periods with low temperature.  相似文献   
150.
采用SBR工艺对高校校园废水进行了处理,运行结果表明:废水中COD含量从200~360mg/L降至60mg/L以下,BOD5含量从70~110mg/L降至20mg/L以下,氨氮含量从60~80mg/L降至10mg/L以下,SS含量从75~160mg/L降至50mg/L以下,达到了北京市DB11307—2005《水污染物排放标准》的二级排放标准。  相似文献   
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