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311.
Takashi Yamamoto Atsushi Ohara Yukio Noma Katsushi Nishizawa Akio Yasuhara Shin-ichi Sakai 《Journal of Material Cycles and Waste Management》2007,9(2):188-193
The photodegradation of tetraphenyltin (TePT) contained in polychlorinated biphenyl (PCB)-based transformer oil simulants
by ultraviolet (UV) irradiation in alkaline 2-propanol solutions was examined. In the absence of PCBs, the TePT level fell
to below 1% of the initial concentration within 30 min. In the absence of both PCBs and an alkali, the concentrations of tri-,
di-, and monophenyltins initially increased to a few milligrams per liter, and then reduced to below the detection limits
within 90 min. The addition of an alkali to the reaction solution slightly accelerated the photodecomposition of TePT. The
decomposition of other phenyltins (PTs) was also accelerated. When PCBs with concentrations of approximately 80 times the
initial TePT concentration were added, only a small fraction of the TePT decomposed within 100 min. Moreover, the levels of
PTs did not change during irradiation. TePT and other PTs did decompose when the level of PCBs was reduced to the same concentration
as that of TePT; however, the decomposition rates were slower than those in the absence of PCBs. In the actual treatment process,
TePT and other PTs in PCB-based transformer oil are decomposed by catalytic reduction, which is used after UV irradiation.
Therefore, in the actual treatment of PCB-based transformer oil wastes, pollution due to PTs can be prevented. 相似文献
312.
Faezeh Ghanati Parviz Abdolmaleki Majid Vaezzadeh Elham Rajabbeigi Mohammad Yazdani 《The Environmentalist》2007,27(4):429-434
In the present research, the effects of static magnetic field, with or without iron on the growth, the activity of certain
enzymes (like polyphenol oxidase and phenyle alanine ammonialyase), the content of phenolic compounds and the essential oil
composition of sweet basil (Ocimum basilicum) were studied. Treatment of plants with static magnetic field with or without iron led to decrease of the growth of plants
as well as decrease in the activity of phenyle alanine ammonialyase and of phenolic compounds content. In addition in those
plants exposed to magnetic field the amount of essential oils, notably of methyl chavicol, was increased. Exposure of plants
to the magnetic field decreased the activity of polyphenol oxidase, whereas treatment of plants with iron when exposed to
magnetic field increased polyphenol oxidase activity. In this group the content of essential oil was reduced. 相似文献
313.
314.
Marshall Flug Wynn R. Walker Gaylord V. Skogerboe 《Journal of the American Water Resources Association》1979,15(4):964-973
ABSTRACT: The Upper Colorado River Basin contains appreciable amounts of undeveloped fuel resources. Large quantities of oil shale, coal, and uranium have attracted recent economic and commercial interests. Development of these resources and subsequent conversion to alternative energy forms require an adequate supply of water. Water use for large scale energy development will place increasing demands on an already overstressed allocation of Colorado River water. Present water quality is at a concentration where increased salinity will result in economic detriments to holders of downstream water rights. The salt and water exchange in mining, processing, and spent fuel disposal processes has been incorporated as part of a two-level minimum cost linear programming algorithm. Mathematical simulation results provide an optimal use of Upper Colorado River water for levels of energy output such that salinity concentrations are maintained below predetermined levels. 相似文献
315.
ABSTRACT: This paper discusses the consumptive water needs of the various energy conversion processes including oil shale retorting, coal gasification and liquefaction, electric power generation, and slurry pipelines. Projected energy development water needs in the upper Colorado River and Upper Missouri River basins are compared with projected agricultural needs and water available. The comparative cost and values of water to energy and agricultural development are discussed to emphasize this as well as the political and social factors entering into the picture. 相似文献
316.
Heavy metals in fly ash from municipal solid waste incinerators are present in high concentrations. Therefore fly ash must be treated as a hazardous material. On the other hand, it may be a potential source of heavy metals. Zinc, lead, cadmium, and copper can be relatively easily removed during the thermal treatment of fly ash, e.g. in the form of chlorides. In return, wet extraction methods could provide promising results for these elements including chromium and nickel. The aim of this study was to investigate and compare thermal and hydrometallurgical treatment of municipal solid waste fly ash. Thermal treatment of fly ash was performed in a rotary reactor at temperatures between 950 and 1050 °C and in a muffle oven at temperatures from 500 to 1200 °C. The removal more than 90% was reached by easy volatile heavy metals such as cadmium and lead and also by copper, however at higher temperature in the muffle oven. The alkaline (sodium hydroxide) and acid (sulphuric acid) leaching of the fly ash was carried out while the influence of temperature, time, concentration, and liquid/solid ratio were investigated. The combination of alkaline-acidic leaching enhanced the removal of, namely, zinc, chromium and nickel. 相似文献
317.
考虑离散油滴在油田废水除油过程中发生的油滴碰撞聚结现象,模拟得出斜板除油器内全部油滴的动态信息,用于斜板除油器除油效率的计算.对矩形同向流斜板除油过程的模拟研究表明:油滴的碰撞聚结会增加斜板除油的效率;当废水的原始含油浓度增大时,斜板除油的效率会增大,碰撞聚结对除油效率提高的影响也越大;废水流动速度提高及斜板的倾斜角度增加均会使斜板的除油效率降低,但此时油滴碰撞聚结对除油效率的影响仍很明显. 相似文献
318.
《环境科学学报(英文版)》2023,35(4):321-332
Sludge is the by-product of wastewater treatment process. Multisource sludge can be defined as sludge from different sources. Based on the sludge properties of five typical cities in the Yangtze River basin, including Jiujiang, Wuhu, Lu'an, Zhenjiang and Wuhan, this study investigated and summarized the characteristic variations and distribution differences of multiple indicators and substances from municipal sludge, dredged sludge, and river and lake sediments. The results demonstrated pH of multisource sludge was relatively stable in the neutral range. Organic matter and water content among municipal sludge were high and varied considerably between different wastewater treatment plants. Dredged sludge had an obviously higher sand content and wider particle distribution, which could be considered for graded utilization depending on its size. The nutrients composition of river and lake sediments was usually stable and special, with lower nitrogen and phosphorus content but higher potassium levels. The sources of heavy metals and persistent organic pollutants in multisource sludge were correlated, generally much higher among municipal sludge than dredged sludge and river and lake sediments, which were the most important limitation for final land utilization. Despite various properties of multisource sludge, the final fate and destination have some overall similarities, which need to be supplemented and improved by standards and laws. The study provided a preliminary analysis of suitable technical routes for municipal sludge, dredged sludge, river and lake sediments based on their different characteristics respectively, which was of great significance for multisource sludge co-treatment and disposal in the future of China. 相似文献
319.
厉建祥 《安全.健康和环境》2010,10(11):5-6
介绍了一起在美国南卡罗来纳州发生的原油管道泄漏事故,分析了事故的主要原因,并对我国原油管道的维护管理提出建议。 相似文献
320.
Shouliang Huo Jingtian Zhang Kevin M. Yeager Beidou Xi Yanwen Qin Zhuoshi He Fengchang Wu 《环境科学学报(英文版)》2023,31(5):1-11
The technique of DGT (diffusive gradients in thin films) using three diffusive gel thicknesses was applied to estimate the mobility and bioavailability of heavy metals in sediments and porewater of Lake Taihu, China. The DGT results showed significantly positive correlations between Co, Pb, Cd and Mn, and Ni and Fe concentrations in porewater. Cu and Zn showed a significantly negative correlation with Mn, due to Cu combination with carbonates and Zn derived from agricultural pollution, respectively. The rank order of average concentrations of Co, Ni and Cd at each station was DGT1.92 > DGT0.78 > DGT0.39, suggesting stronger resupply from sediments to porewater when using thicker diffusive gels. Comparing centrifugation and DGT measurements, Co, Ni and Cd are highly labile; Mn and Fe are moderately labile; and Cu, Zn and Pb are slightly labile. The variations of AVS concentrations in sediment cores indicate that metal sulfides in deeper layers are easily diffused into surface sediments. 相似文献