19 resultados para Life Lost

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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近年来各种环境污染事故频发,据统计仅2001~2003年间,发生的各类环境污染事故就高达5606次,其中水污染事故3235次,占全部的57.7%。这些事故不仅给人民生命财产造成巨大损失,也给生态环境造成严重的破坏。因此开发安全高效的应急处理技术迫在眉睫。本研究以筛选高效苯胺降解菌为基础,通过对高效菌降解性能的研究指导将高效菌作为功能郡主投加到已有生物处理系统强化应急处理苯胺突发污染事故废液,取得了良好的效果。 苯胺高效降解菌AN-P1为红球菌(Rhodococcus sp.),其通过间位途径降解苯胺,AN-P1利用苯胺生长和降解的最佳pH为6,最适浓度为2000 mg/L,最适温度为30 ℃,最佳接种量为0.3‰。AN-P1降解含500 mg/L、1000 mg/L、2000 mg/L苯胺的培养物分别经过28 h、24 h、32 h降解,出水苯胺含量能达到《污水综合排放标准》(GB8978-1996)一级标准。但由于苯胺降解过程中释放了大量氨氮,出水氨氮仍较高未能达标排放。而常规SBR系统应急处理效果较差,苯胺和COD去除率均低于10%,出水未能达标排放。活性碳吸附后的回收和后续处理也会带来操作不变和二次污染问题,且处理后出水往往难于达标排放,尚需进行进一步处理。 生物处理系统应急处理后恢复运行处理效果监测和PCR-DGGE图谱分析显示,用AN-P1菌强化应急处理系统后不仅能快速高效的去除苯胺,而且可以有效保障处理系统对污染物的净化性能,有效的保护系统中的功能微生物免受苯胺毒害。 研究结果表明,从实际处理效果、对原有生物系统性能保护及实际应用操作等多方面考虑,用AN-P1菌强化应急处理苯胺突发污染事故在技术上都是可行的。本研究为应急处理苯胺突然污染事故废液提供了新的方法。 Recent years, environment pollution accidents happened frequently, the data showed that there are 5606 accidents between 2001 and 2003, including 3235 water environment accidents, which is 57.7% of all. These accedents not only caused money lost and life lost but also caused serious damage to the ecologicl environment. So exploring highly-effective and secure methods to solve these accidents is an urgent mission. We screened a highly-effective aniline-degrading bacterium and did some researches on its ability to degrade aniline, in order to guide the emergency treatment of aniline containing wastewater that caused by sudden accident pollution with bioaugmentation. A highly-effective aniline-degrading bacterium AN-P1 was isolate and characterized as Rhodococcus sp. It degrades aniline through meta-cleavage pathway. The optimal pH and temperature for cell growth and aniline degradation were 6 and 30 ℃, respectively, and the opitimal concentration of aniline was 2000 mg/L, the optimal inoculation amount was 0.3‰.It took bacterium AN-P1 only 18 h, 24 h and 32 h, respectively, for the treatment of MSB containing 500 mg/L, 1000 mg/L, 2000 mg/L aniline to meet the first grade of national some of the NH4+-N which caused by aniline degradation. It took bacterium AN-P1 only 10 h, 20 h and 32 h, respectively, for the treatment of wastewater containing 500 mg/L, 1000 mg/L, 2000 mg/L aniline to meet the first grade of national integrated wastewater discharge standard. The bacterium AN-P1 can also remove some of the NH4+-N which caused by aniline degradation. It took bacterium AN-P1 only 10 h, 20 h and 32 h, respectively, for the treatment of wastewater containing 500 mg/L, 1000 mg/L, 2000 mg/L aniline to meet the first grade of national integrated wastewater discharge standard. By combing AN-P1 with regular SBR system, it took only 36 h for the emergency treatment of wastewater containing 2000 mg/L aniline under simulating engineering conditions to meet the discharge standard. While the NH4+-N of effluent can not meet the standard because of the high amount NH4+-N caused by aniline degradation. The regular SBR system was not good at aniline and COD removal. The removal efficiency of which are less than 10%. It cost 67.8 g activated carbon to absorbed 1000 mg aniline. It is inconvenient to transport and use it for the emergency treatment of aniline when the sudden pollution accident happened. Meanwhile, it was complex ad hard to recycle the activated carbon and treat the aniline wastewater get from activated carbon recycling too. Hard to meet the effluent standard was also a problem of activated carbon absorption method. According to the PCR-DGGE profile and removal efficiency of pollutants and COD when the systerm recover from emergency treatment, AN-P1 can efficiently protect the microbial community of regular activated sludge system against the aniline. It proved that combing AN-P1 with regular biological system is a feasible strategy for emergency treatment of aniline sudden pollution accident. The research offered a new way for emergency treatment of aniline sudden pollution accident.

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Changes of the gonad. survival rate, and life span of the precocious (i.e., sexually mature in their first October-November, at the age of 5 or 6 months) Chinese mitten crab (Eriocheir sinensis) were studied in a small, shallow, macrophytic, freshwater lake along the middle reaches of the Changjiang River, China. The gonosomatic index (GSI) reached peak during the next March when the female GSI was 12.32 +/- 1.75 SD% and the male GSI A as 4.24 +/- 0.19%. The sexual glands degraded from then on. In the first ten-day period of the following July, there was no complete ovum in the ovary. and the sperm became thin and lost adhesion. The population declined sharply from November to July, and the last one (a female) died in the middle of July, which indicated that the life span of the precocious crab was about 12 months (from larval hatching in June to death in July of next year). The survival curve might be expressed as Y = 1.09exp(-0.018x) (Y survival rate; x: days) for the precocious crabs stocked in experimental cages.

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The progress of the research activities on space material sciences, microgravity ‰uid physics and combustion, space life sciences and biotechnology research, fundamental Physics in China are brie‰y summarized in the present paper. The major space missions and experimental results obtained on board the Chinese recoverable/non-recoverable satellites and the Chinese manned spaceship named ``Shen-Zhou'' are presented summarily. The recent main activities of the ground-based studies in China are introduced in brief.

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The LY12-cz aluminium alloy sheet specimens with a central hole were tested under constant amplitude loading, Rayleigh narrow band random loading and a typical fighter broad band random loading. The fatigue life was estimated by means of the nominal stress and the Miner's rule. The stress cycles were distinguished by the rainflow count, range count and peak value count, respectively. The comparison between the estimated results and the test results was made. The effects of random loading sequence and small load cycles on fatigue life were also studied.

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The progress of the research activities on space material sciences, microgravity ‰uid physics and combustion, space life sciences and biotechnology research, fundamental Physics in China are brie‰y summarized in the present paper. The major space missions and experimental results obtained on board the Chinese recoverable/non-recoverable satellites and the Chinese manned spaceship named ``Shen-Zhou'' are presented summarily. The recent main activities of
the ground-based studies in China are introduced in brief.