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741.
散装液体危化品码头的污染原因分析及防控对策 总被引:1,自引:0,他引:1
介绍了液体危化品的特点,对散装液体危化品码头的污染原因进行了分析,并提出了相应的防控对策,为确保码头安全稳定运行提供了保障. 相似文献
742.
通过对锅炉型号的简要介绍,提高对锅炉的认识,增强在污染源动态更新调查表的填报过程中锅炉技术指标的填报能力是十分必要的。 相似文献
743.
Copper-exchanged chabazite (Cu/CHA) catalysts have been found to be affected by alkali metal and alkaline earth ions. However, the effects of Na+ ions on Cu/SAPO-34 for ammonia selective catalytic reduction (NH3-SCR) are still unclear. In order to investigate the mechanism, five samples with various Na contents were synthesized and characterized. It was observed that the introduced Na+ ion-exchanges with H+ and Cu2 + of Cu/SAPO-34. The exchange of H+ is easier than that of isolated Cu2 +. The exchanged Cu2 + ions aggregate and form “CuAl2O4-like” species. The NH3-SCR activity of Cu/SAPO-34 decreases with increasing Na content, and the loss of isolated Cu2 + and acid sites is responsible for the activity loss. 相似文献
744.
1IntroductionCalciumchlorideisoftenusedinthefieldofsoilstabilizationandraisingdustcontrolbecauseitcanreactwithwaterglas(Wu,19... 相似文献
745.
746.
The formation of hydrogen sulfide in biofilms and sediments in sewer systems can cause severe pipe corrosions and health hazards, and requires expensive programs for its prevention. The aim of this study is to propose a new control strategy and the optimal condition for sulfide elimination by intermittent nitrate dosing in sewer sediments. The study was carried out based on lab-scale experiments and batch tests using real sewer sediments. The intermittent nitrate dosing mode and the optimal control condition were investigated. The results indicated that the sulfide-intermittent-elimination strategy by nitrate dosing is advantageous for controlling sulfide accumulation in sewer sediment. The oxidation–reduction potential is a sensitive indicator parameter that can reflect the control effect and the minimum N/S(nitrate/sulfide)ratio with slight excess nitrate is necessary for optimal conditions of efficient sulfide control with lower carbon source loss. The optimal control condition is feasible for the sulfide elimination in sewer systems. 相似文献
747.
748.
在中国农村发展过程中,水环境污染已严重制约了当前农村经济的健康持续发展,探究农村地区水污染的成因,寻求解决污染的对策已十分迫切。本文在对江苏省农村水环境污染现状进行调查的基础上,运用AHP层次分析法分析现阶段江苏农村发展过程中水污染的形成机理,包括经济发展因素、社会公众因素、政策法规因素,并提出相关结论与建议。 相似文献
749.
Dyeing fabrics in supercritical carbon dioxide (SCD) instead of water can save energy, reduce water use and prevent pollution. The special pilot plant was designed to test dyeing procedures in supercritical carbon dioxide and the analyses of the results indicate major benefits as compared to water based procedures. The dyeing of polyethylene terephthalate (PET) fabric in supercritical carbon dioxide using special pilot plant was investigated. Disperse dye, C.I. (color index) Disperse Blue 79, was used in this study. After dyeing, rinsing in supercritical carbon dioxide, which removes the excess dyes, was also discussed. At the same dyeing conditions, K/S (color yield) of dyed fabric significantly increased with increasing the dye concentration from 1% o.w.f. (on weight of fabric) to 5% o.w.f. Dyeing temperature and pressure had a strong influence on the color yield. When the temperature rose above 110 °C, the increase in color yield was obvious. At 20 MPa, 120–130 °C, dyeing reached equilibrium after 60 min. The excess dye of the dyed PET fabric was small. The suitable condition in supercritical carbon dioxide for removal of excess dye from the dyed fabric was 70 °C, 20 MPa. The PET fabric dyed in supercritical carbon dioxide had good fastness and physical properties. 相似文献
750.
The genetic composition of Poa annua L, populations with a series of traffic pollution was studied by starch electrophoresis. Five enzyme systems were stained. The results showed that: (1) Traffic pollution can dramatically change genotypic frequencies at some loci of P. annua populations. Significant deviations from HardyWeinberg equilibrium were observed on loci Fe - 1 and Me due to the excess of heterozygotes in some populations.(2) The effective number of alleles per locus and the observed and expected heterozygosity were higher in the pollution series than in the clear control site(Botanic Park population), but the increase was not related with the pollution extent. (3) Most genetic variation was found within populations, and only 6.21% was among populations of the polluted series. Slightly higher differentiation( FST = 7.98%) was observed when the control population was included. (4) The calculated gene flow(Nm) is 2.8841 per generation. The mean of genetic identity is 0.9864 and the genetic distance average to 0.0138. 相似文献