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791.
792.
Energy Service Companies (ESCOs) and the energy market for ESCO financing have been developing since 1976 when oil prices increased dramatically. ESCOs’ services cover projects in many energy areas, including energy extraction, power generation, energy conversion, transportation, power transmission, energy consumption, project financing, energy project audits, monitoring, and energy savings verification. In developing countries, there are many barriers in the energy market that are preventing ESCOs from developing. These barriers include lack of appropriate policy, financial mechanisms, and local capacities for ESCO development and management. Over the past 20 years, the Global Environment Facility (GEF) financed 39 ESCO projects in 25 countries and regions to remove these barriers. The results of these projects show that some countries, such as China, are very successful in ESCO development, but others are not. Different models of ESCOs in different financial markets in various countries are analyzed; and case studies are undertaken for China, India, Ukraine, and Brazil. This article concludes that, while developing financial markets for ESCOs, countries need to consider (1) initiating national government policy to stop energy subsidies and to reform energy pricing, (2) establishing a real, market based financial mechanism for ESCOs, (3) involving the private sector in project co-financing, (4) creating incentives to ESCOs in the market by investing part of government revenue from energy tax, and (5) incentivizing ESCOs by government corporate tax exemption.  相似文献   
793.
运用探地雷达进行加油站埋地罐区油品泄漏检测,先后对8座加油站进行了埋地罐区泄漏测试,发现某加油站埋地罐区的疑似泄漏区域,并对疑似泄漏区域进行了验证确认。  相似文献   
794.
好氧-厌氧污泥耦合白腐真菌单元对焦化废水的处理   总被引:1,自引:0,他引:1  
白腐真菌因能分泌胞外木质素降解酶降解难降解有机污染物,而在难降解有机废水处理中具有巨大应用潜力.其研究常采用白腐真菌直接处理废水,很少关注常规生物法耦合白腐真菌的处理方式.基于此,分别采用白腐真菌和好氧-厌氧污泥耦合Phanerochaete Chrysosporium处理焦化废水以考察后者的可行性.在好氧-厌氧污泥耦合P.chrysosporium的处理中,仅采用3 d的处理时间,好氧-厌氧污泥可将6097 mg·L~(-1)的COD和351 mg·L~(-1)的氨氮分别降至1634~1684 mg·L~(-1)和102~117 mg·L~(-1);进而固定化P.chrysosporium将COD和氨氮再次分别降至1322~1372 mg·L~(-1)和16~62 mg·L~(-1).最终COD和氨氮的去除率分别达77%~78%和82%~95%,这表明:好氧-厌氧污泥耦合P.chrysosporium处理焦化废水可在更短的处理周期完成比直接采用白腐真菌处理更好的处理效果,此思路合理可行.  相似文献   
795.
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   
796.
冻土区输油管道在投产运行过程中,由于管道沿线受到冻融影响引起的管线变形破坏现象比较普遍。已建的中俄原油管线由漠河进入中国,经过我国北方多年冻土区和季节冻土区直至大庆。输油管道在寒区运行过程中与周围土体发生了热交换,使原自然土层热交换体系改变,进而对运行的管线造成不利的影响如冻胀和融沉。本文对此进行研究为管道安全运行提供参考依据。  相似文献   
797.
Liu  Jinfeng  Yuan  Dong  Lu  Ming  You  Yong  Zhang  Guangze  Feng  Tao  Wang  Dong  Lin  Zhiheng 《Environmental Fluid Mechanics》2021,21(6):1253-1271
Environmental Fluid Mechanics - Experimental tests were conducted on a rectangular flume with different grid-type dam grid sizes, channel slopes and debris flow bulk density. We use the Bernoulli...  相似文献   
798.
为了阐明改变肥料养分投入后土壤微生物特性的短期变化,采集长期定位有机无机肥配施的红壤水稻土,通过室内培育试验,观测添加不同肥料养分后土壤微生物生物量碳及BIOLOG群落功能多样性的变化.结果表明,长期有机无机肥配施土壤中添加无机肥料养分短期内( 185 d)降低了15%~22%的微生物生物量碳含量和55.6%的微生物群落平均光密度;添加有机肥料养分短期内提高了8%~42%的微生物生物量碳含量和992%的微生物群落平均光密度;而不添加肥料养分短期内提高了501%的微生物群落平均光密度,降低了微生物群落均一性,但对微生物生物量碳含量影响不大.此外,添加不同肥料养分均改变了土壤微生物群落碳源代谢模式.长期配施有机无机肥土壤中添加不同肥料养分后土壤微生物生态特征发生明显变化,其差异体现在微生物生物量碳与微生物碳源利用特性的变化上.  相似文献   
799.
A total of 60 children (31 males and 29 females) between the ages of 3 and 12 years were randomly selected from Lanzhou City in Gansu Province, northwest China. Hand (soil/dust) SD samples from these children were collected using hand wipes. We determined the approximate amounts of hand SD and the concentrations of three tracer soil elements (Ce, Y, and V) in these samples. The approximate amounts of hand SD ranged from 42.28 to 173.76 mg, with a median value of 85.42 mg. In addition, the mean amounts of hand SD estimated using the concentrations of Ce, Y, and V in the samples were 4.63, 3.43, and 3.42 mg, respectively. The amount of hand SD varied greatly among the age groups: primary school children had more hand SD than kindergarten children, males had more hand SD than females, and children from rural areas had more hand SD than those from urban areas. The rates of daily ingestion of hand SD for kindergarten and primary school children were estimated to be 7.73 and 6.61 mg/day, respectively.  相似文献   
800.
针对多数电厂脱硫石膏含水率偏高的情况,对真空皮带脱水机效果的影响因素进行阐述,主要包括真空皮带脱水机中石膏浆液物料的特性影响、脱硫反应条件的影响和真空皮带脱水机影响因素及处理方法,并根据安徽淮南平圩发电有限责任公司脱硫工程一、二期运行情况提出部分建议。  相似文献   
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