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151.
南开菊酯(高效反体氯氰菊酯),是一种新型广谱杀虫剂,经研究可被微生物降解。其溶液中细菌总数的消长,与其降解速率呈正相关关系,说明南开菊酯可被微生物分解利用,在研究土壤混合菌对其降解作用的同时,发现筛选出优势菌株(NK102)。  相似文献   
152.
扬中市地表水的致突变性研究   总被引:2,自引:0,他引:2  
本研究诮蚕豆根尖微枋试验对扬中市不同水体的遗传毒物污染状况进行了初步调查。结果表明,扬中市水体的遗传毒物污染集中在汇集了乡镇工业废水和生活污水的排污河道和死水沟塘。各主要河道及通江闸口基本没有污染。除新坝大桥处,各样点底泥浸担液的微枋率均高于相应原水样微核率。  相似文献   
153.
通过对地面水、医院污水、无菌生理盐水加入标准菌的细菌总数和大肠菌群的稳定性分析,筛选出了适宜测定考核的未知标样:通过现场实际考核,确定了考核结果评价体系及质量保证体系,这将对环境细菌学检测数据的质量起到了监控作用。  相似文献   
154.
分析锻造企业生产的信息流和物流的规律,建立了相应的数据库,并介绍了锻造企业计算机信息管理MIS系统的开发步骤、原则、功能及主要特色。  相似文献   
155.
旋转式滗水器是SBR工艺处理法中重要装置.针对其实际运行过程中出现的问题,通过建立旋转式滗水器的数学模型,并进行受力分析,找出了工作中受力的变化规律.在此基础上对其进行了改进设计,经过实际运用表明,理论分析是正确的.这对于SBR工艺处理法的实际运行具有良好的推进作用.  相似文献   
156.
研究了ph在3-5的范围内,大气浓度水平下、铁、锰和铁锰共存时的注相催化氧化的动力学,发现在不同的条件下反应级数,表观反应速率常数和活化能不同,证实了铁,锰对S(Ⅳ)的液相催化氧化有明显的协同作用,并给出了许多反应体系的经验速率表达式。  相似文献   
157.
附着态半导体光催化剂光解可溶性染料的研究   总被引:42,自引:0,他引:42  
以300W中压汞灯和日光为光源,研究了将TiO2等半导体粉末附着在海砂和玻璃表面对直接耐晒大红4BS(下简称4BS)、活性黑KN-B(下简称KN-B)和亚甲基蓝(下简称MB)水溶液的催化光解。结果表明:几种染料均显光解;光解为一级动力学反应;附着复合的TiO2-Fe2O3、TiO2-WO3比附着单一的TiO2光催化效果好;附着态TiO2重复使用15次(每次8h)后催化能力降低17.9%。以基态电  相似文献   
158.
Dye wastewater containing heavy metal ions is a common industrial effluent with complex physicochemical properties.The treatment of metal–dye binary wastewater is difficult.In this work,a novel in-situ ferrite process(IFP) was applied to treat Methylene Blue(MB)–Cu(II)binary wastewater,and the operational parameters were optimized for MB removal.Results showed that the optimum operating conditions were OH/M of 1.72,Cu~(2+)/Fe~(2+)ratio of 1/2.5,reaction time of 90 min,aeration intensity of 320 mL/min,and reaction temperature of40°C.Moreover,the presence of Ca~(2+)and Mg~(2+)moderately influenced the MB removal.Physical characterization results indicated that the precipitates yielded in IFP presented high surface area(232.50 m2/g) and a multi-porous structure.Based on the Langmuir model,the maximum adsorption capacity toward MB was 347.82 mg/g for the precipitates produced in IFP,which outperformed most other adsorbents.Furthermore,IFP rapidly sequestered MB with removal efficiency 5 to 10 times greater than that by general ferrite adsorption,which suggested a strong enhancement of MB removal by IFP.The MB removal process by IFP showed two different high removal stages,each with a corresponding removal mechanism.In the first brief stage(5 min),the initial high MB removal(~95%)was achieved by predominantly electrostatic interactions.Then the sweep effect and encapsulation were dominant in the second longer stage.  相似文献   
159.
SUMMARY

During the past half century, China has experienced increasingly severe land degradation, soil erosion, and desert expansion. Desertification is affecting one third of China's total territory and the annual accelerating rate of desertification spread is as high as 2460 km2 in China. In 1996, China developed a National Action Programme to Combat Desertification (NAP), which is aimed to apply new legal measures and technical approaches to slow down desertification processes and achieve a long-term goal — control desertification and alleviate poverty through continuous efforts to fight against desertification, stabilize mobile dunes, revegetate degraded rangeland and control soil erosion in arid, semi-arid, and dry sub-humid areas. The long-term and integrated strategies of China's NAP result in encouragement of social participation, legal institutional guarantees, policy making, and establishment of demonstrations/pilot projects to combat desertification at both national and provincial level.  相似文献   
160.
Multivariate analysis including correlation, multiple stepwise linear regression, and cluster analyses were applied to investigate the heavy metal concentrations (Cd, Cu, Fe, Ni, Pb, and Zn) in the different parts of bivalves and gastropods. It was also aimed to distinguish statistically the differences between the marine bivalves and the gastropods with regards to the accumulation of heavy metals in the different tissues. The different parts of four species of bivalves and four species of gastropods were obtained and analyzed for heavy metals. The multivariate analyses were then applied on the data. From the multivariate analyses conducted, there were correlations found between the soft tissues of bivalves and gastropods, but none was found between the shells and the soft tissues of most of the molluscs (except for Cerithidea obtusa and Puglina cochlidium). The significant correlations (P < 0.05) found between the soft tissues were further complemented by the multiple stepwise linear regressions where heavy metals in the total soft tissues were influenced by the accumulation in the different types of soft tissues. The present study found that the distributions of heavy metals in the different parts of molluscs were related to their feeding habits and living habitats. The statistical approaches proposed in this study are recommended for use in biomonitoring studies, since multivariate analyses can reduce the cost and time involved in identifying an effective tissue to monitor the heavy metal(s) bioavailability and contamination in tropical coastal waters.  相似文献   
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