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131.
IVP活性炭脱硫性能的研究   总被引:2,自引:0,他引:2  
采用IVP活性炭吸附法治理污水场隔油池散发的多组分含H2 S废气。研究表明 ,复杂的废气组分并未影响到该活性炭对H2 S的吸附性能 ,且由于处理的废气湿度较高 ,使吸附性能有了较大的提高  相似文献   
132.
Preface     
正Air pollution as well as climate change and their possible effects on the environment,ecosystems and human health,are pressing challenges.Nowadays,it is clear that sustainable societal development cannot remain solely wealth-oriented,but must take into account the present and future environmental issues.However,this approach is possible only if scientifically sound knowledge in all environmental areas becomes available to our societies and decision makers,which requires a firm  相似文献   
133.
为评估污染减排对南京青奥期间空气质量影响,利用排放系数法估算减排量,利用敏感系数分析管控措施有效性.结果表明:经过8月份的强力减排,SO2、NO2、PM2.5、PM10、CO与VOCs减排量分别为3438、4402、3177、7249、15890与4052 t,减排比例分别为-29%、-25%、-45%、-65%、-26%、-22%;环境空气中SO2、NO2、PM2.5、PM10、CO与O3浓度环比7月分别下降了-18.8%、-15.0%、-37.0%、-35.4%、-7.1%与-50.4%;敏感系数排序为:O3>PM2.5>SO2>NO2>PM10>CO,除了O3外,其余污染物浓度下降比例小于减排比例,说明要取得一定空气质量改善,需要付出更多的减排努力.  相似文献   
134.
By enrichment culturing of the sludge collected from the industrial wastewater treatment pond, we isolated a highly efficient nicosulfuron degrading bacterium Serratia marcescens N80. In liquid medium, Serratia marcescens N80 grows using nicosulfuron as the sole nitrogen source, and the optimal temperature, pH values, and inoculation for degradation are 30–35°C, 6.0–7.0, and 3.0% (v/v), respectively. With the initial concentration of 10 mg L?1, the degradation rate is 93.6% in 96 hours; as the initial concentrations are higher than 10 mg L?1, the biodegradation rates decrease as the nicosulfuron concentrations increase; when the concentration is 400 mg L?1, the degradation rate is only 53.1%. Degradation follows the pesticide degradation kinetic equation at concentrations between 5 mg L?1 and 50 mg L?1. Identification of the metabolites by the liquid chromatography/mass spectrometry (LC/MS) indicates that the degradation of nicosulfuron is achieved by breaking the sulfonylurea bridge. The strain N80 also degraded some other sulfonylurea herbicides, including ethametsulfuron, tribenuron-methyl, metsulfuron-methyl, chlorimuron-ethyl,and rimsulfuron.  相似文献   
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137.
The marine sponge Dysidea fragilis from El Mar Menor, a hypersaline coastal lagoon (Murcia, Spain), contains the furanosesquiterpenoid ent-furodysinin as the major secondary metabolite. D. fragilis emits a defensive white fluid when it is disturbed. Electron micrographs of this fluid revealed intact vesiculated cells together with other amorphous material. Dissociated cells are more rounded in shape but maintain the same ultrastructural features as cells observed in ultra-thin sections of the whole sponge. The defensive secretion is composed mainly of sponge cells with abundant light vesicles. Sometimes these light vesicles appear to open into the intercellular space; this correlates with surface blebs on these cells observed under scanning electron microscopy. The intracellular location of ent-furodysinin was confirmed by Erlich staining. In laboratory assays, we examined the role of ent-furodysinin as a feeding deterrent to generalist fish predators. It was isolated from D. fragilis and incorporated into a carrageenan-based artificial diet. The addition of ent-furodysinin to the artificial diet reduced feeding by the fish Thalassoma pavo. Similarly, fish did not feed on artificial diet above which defensive secretion of D. fragilis had been ejected with a small syringe. Received: 4 June 1997 / Accepted: 28 January 1998  相似文献   
138.
One of the objectives of the new State of Croatia, as a Mediterranean country oriented towards tourism, is safety of its air traffic. The frequency of use of Zagreb airport is currently 688 flights, or about 20000 passengers a week. In 1996, research was carried out at the airport concerning air traffic safety with respect to the presence of birds on the airfield. Biological methods, in which birds were chased away by means of trained birds of prey, were used. For the Zagreb airport experiment nine birds involving three different species: Falco peregrinus, Accipiter gentilis and Falco cherrug were utilised. The results showed that the air traffic safety on Zagreb airport with regard to possible bird-plane strikes improved.Other bird clearing methods, applied over the 1987–1996 period also reduced bird-plane interferences but were noted to be less effective. With the biological, bird of prey method, 100% temporary clearance was achieved. Habitat modification, which involved removal from the airport vicinity of all factors attractive to the birds, only removed 20–30% of the birds, but this was of a more permanent nature. Use of fire-arms achieved a 80–90% temporary bird clearance. A combination of all three methods would appear to be most effective and measures for further monitoring for safe air traffic movement at Zagreb airport are proposed.  相似文献   
139.
在安全生产总体形势逐步好转的情况下,中国职业病危害致病因素中粉尘和噪声占有不可忽视的分量.本文通过对国内外在线监测技术的发展现状的详细分析,引入国内外先进的粉尘和噪声在线监测技术构建了职业安全健康在线监测系统基本架构,对其基本工作性能和实际能产生的工作效果进行描述,并对其产生的科技进步性进行阐述.  相似文献   
140.
作为一种曾经广泛使用的氯化烃杀虫剂,DDT及其主要代谢产物DDE和DDD(合称为DDTs)是一类典型的具有持久性和生物累积性的有毒污染物。亲脂性和持久性使得DDTs可以通过食物链进行生物放大,从而对处于高营养级的水生哺乳动物造成严重的毒害作用。在综述DDTs对哺乳动物的毒性研究基础上,采用物种敏感度分布(species sensitivity distribution,SSD)和毒性百分数排序法(toxicity percentile rank method,TPRM)推导DDTs保护水生哺乳动物的组织残留基准(Tissue Residue Guideline,TRG)。使用SSD和TPRM得到的TRG分别为23.9和22.7 ng·g-1食物(湿重)。相应的,DDTs保护水生哺乳动物的水质基准分别为188.2和178.7 pg·L-1。依据研究得到的DDTs的组织残留基准及其在鱼类体内的含量评估对水生哺乳动物的风险。研究结果可用于评估DDTs对水生哺乳动物的生态风险,并为DDTs的风险管理提供理论依据。  相似文献   
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