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171.
森林碳汇资源是开展森林碳汇贸易的基础。森林碳汇潜力的定量评价,将为森林碳汇贸易提供可靠的依据。在对森林碳汇资源开发潜力的定量方法进行深入研究的基础上,以黑龙江省为案例进行潜力评价,明确了黑龙江省具有巨大的森林碳汇增量潜力,提出了进一步发展森林碳汇贸易及构建森林碳汇交易市场的可行性。  相似文献   
172.
科学加强环境应力筛选以提高电子产品可靠性   总被引:1,自引:0,他引:1  
雷江涛 《环境技术》2012,37(1):46-48
针对其电子产品的可靠性越来越高的需求,本文提出了为剔除电子产品早期故障,环境应力筛选(ESS)已成为不可缺少的一个环节。通过分析如何科学加强环境应力筛选分析,以提高电子产品可靠性水平。  相似文献   
173.
通过对2006年7月- 2007年6月云南地闪定位网探测资料和玉溪大气电场仪资料分析,研究了高原晴天大气电场和雷暴天气过程的电场演变特征.结果表明:高原晴天大气电场具有明显的日变化和月变化特征.低纬高原地区雷暴云具有偶极性和三极性两种结构,但大多数雷暴具有偶极性电荷结构,不同电荷结构的雷暴云的放电特征不同,偶极性时主要为负地闪,地闪活动较活跃;三极性时主要是正地闪,地闪活动较少.根据雷暴云近地面电场变化特征,探讨了大气电场仪预警地闪的方法,首次提出极性变化预警法,其命中率和提前预警时间都明显优于阈值预警法.  相似文献   
174.
产业升级是一项系统工程,目前面临一些约束条件,制约了产业升级的成效。本文分析了三个方面的约束因素:有效需求约束、供给约束、制度约束,并提出新形势下的产业结构调整对策:调整需求结构、要素投入结构、分配结构,扩大内需;调整三次产业结构;构建有利于产业结构调整的体制机制。  相似文献   
175.
杨永钦  李斌 《四川环境》2008,27(2):123-126
文章介绍了潜在照射的主要来源及危害。结合实际应用中的具体情况,对其使用实践中可能导致的潜在危害作了简单的分析,并根据ICPLP的相关建议和国家相关的具体要求,提出在放射源应用领域潜在照射控制的主要原则和措施。  相似文献   
176.
Goals, Scope and Background It has been observed that hydrocarbon treated wastewaters still contain high COD and a number of intermediates. This suggests that the required catabolic gene pool for further degradation might be absent in the system or, that its titer value is not significant enough. By providing the desired catabolic potential, the overall efficiency of the treatment system can be improved. This study aims to demonstrate this concept by bioaugmentation of a lab-scale reactor treating refinery wastewater with a consortium having the capacity to complement the alkB genotype to the available microbial population. Methods Two reactors were set up using activated biomass collected from a refinery treatment plant and operated at a continuous mode for a period of 8 weeks. The feed to both reactors was kept constant. Crude oil was spiked regularly. One reactor was bioaugmented with a consortium previously described for crude oil spill remediation. The efficiency of the bioaugmented reactor was demonstrated by reduced COD. The changes in the microbial population over a period of time were analyzed by RAPD. Catabolic activity of the biomass in both reactors was monitored by PCR. The presence of the catabolic loci was confirmed by Southern Hybridization. Results and Discussion 52.2% removal of COD was observed in the bioaugmented reactor while only 15.1% reduction of COD was observed in the reactor without bioaugmentation. The change in microbial population can be seen from the 4th week, which also corresponds to improved catabolic activity. The presence of the bedA locus was seen in all samples, which indicates the presence of aromatic degraders, but the appearance of the alkB locus, from the 6th week onwards, which was observed only in the samples from the bioaugmented reactor. The results suggest that the gene pool of the bioaugmented reactor has catabolic loci that can degrade accumulated intermediates, thus improving the efficiency of the system. Conclusions In this study, improvement of efficiency of bioremediation was demonstrated by addition of catabolic loci that are responsible for degradation. Bioaugmentation was carried out in biomass that was collected from an ETP (effluent treatment plant) treating hydrocarbon containing wastewater to study the strategies for improvement of the treatment system. Biostimulation, only marginally improved the efficiency, when compared to bioaugmentation. The improved efficiency was demonstrated by COD removal. The presence of the alkB locus suggests the importance of a catabolic gene pool that acts on accumulated intermediates. It is well documented that straight chain aliphatics and intermediates of aromatic compounds after ring cleavage, accumulate in refinery wastewater systems, thereby hindering further degradation of the wastewater. Supplementation of a catabolic gene pool that treats the lower pathway compounds and alkanes will improve the overall efficiency. In this study, results suggest that the alkB locus can also be used to monitor the degradative mode of the activated biomass. Recommendations and Perspective . Pollution from petroleum and petroleum products around the globe are known to have grave consequences on the environment. Bioremediation, using activated sludge, is one option for the treatment of such wastes. Effluent treatment plants are usually unable to completely degrade the wastewater being treated in the biological unit (the aerator chambers). The efficiency of degradation can be improved by biostimulation and bioaugmentation. This study demonstrates the improved efficiency of a treatment system for wastewater containing hydrocarbons by bioaugmentation of a consortium that supports degradation. Further experiments on a pilot scale are recommended to assess the use of bioaugmentation on a large scale. The use of molecular tools, like DNA probes for alkB, to monitor the system also needs to be explored.  相似文献   
177.
A historical input of trace metals into tidal marshes fringing the river Scheldt may be a cause for concern. Nevertheless, the specific physicochemical form, rather than the total concentration, determines the ecotoxicological risk of metals in the soil. In this study the effect of tidal regime on the distribution of trace metals in different compartments of the soil was investigated. As, Cd, Cu and Zn concentrations in sediment, pore water and in roots were determined along a depth profile. Total sediment metal concentrations were similar at different sites, reflecting pollution history. Pore water metal concentrations were generally higher under less flooded conditions (mean is (2.32 ± 0.08) × 10−3 mg Cd L−1 and (1.53 ± 0.03) × 10−3 mg Cd L−1). Metal concentrations associated with roots (mean is 202.47 ± 2.83 mg Cd kg−1 and 69.39 ± 0.99 mg Cd kg−1) were up to 10 times higher than sediment (mean is 20.48 ± 0.19 mg Cd kg−1 and 20.42 ± 0.21 mg Cd kg−1) metal concentrations and higher under dryer conditions. Despite high metal concentrations associated with roots, the major part of the metals in the marsh soil is still associated with the sediment as the overall biomass of roots is small compared to the sediment.  相似文献   
178.
张华 《四川环境》2008,27(1):40-41,51
介绍了环境监测信息网络的组成、作用于流通范围,提出了环境监测信息的构架、环境数据库的设计原则、环境监测应用软件的开发思路,以及环境监测信息网络的管理与维护措施。  相似文献   
179.
依据田间实测资料,分析了南亚热带丘陵赤红壤-果树-大气连续体中的能量变化及其分布规律、结果表明,土壤基质势的年度变化特征说明南亚热带丘陵赤红壤存在明显的湿季和旱季.果树叶水势随土壤基质势、大气水势、气温及大气相对湿度的变化而变化,荔枝、龙眼叶水势的变化比芒果叶水势的变化大.以荔枝、芒果和龙眼作为供试植物,水分从土壤到达植物根表皮、进入根系并通过植物茎到达叶片,其能量降低分别约为0.9063~1.7428、0.2818~0.6979和0.2904~1.8707MPa;水分从叶部汽化扩散到大气中,其能量降低分别达15.1491~57.3669、15.4491~58.4036和14.5824~56.9536MPa,说明水流在南亚热带丘陵赤红壤-果树-大气连续体中运移时,其能量主要消耗在由叶部到大气这一环节上。  相似文献   
180.
河北省钢铁工业主要大气污染物减排潜力分析   总被引:1,自引:0,他引:1  
通过对河北省钢铁工业存在问题的分析,得出我省钢铁行业主要大气污染物为二氧化硫和粉尘.结合我省钢铁企业的实际情况,从工程技术、政策管理等方面提出相应治理措施,并对"十一五"期间我省钢铁行业二氧化硫和粉尘减排效益进行预测.预测结果显示:采用所建议的减排措施后,我省钢铁工业二氧化硫减排量对全省"十一五"减排计划的贡献率为81.4%;粉尘可减排60%.  相似文献   
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