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91.
中国成功实现了所占全球经济份额的快速增加,但在全球能源消耗方面,中国所占的份额增长更为迅速。由于劳动生产率得以提高,中国保持了较高的经济增速,同时减缓了能源需求的增速。作为全球第二大能源消耗国,中国可望进一步参与国际能源政策磋商,提供与其地位相称的、充分的能源供求数据,以便增强全球能源市场的可预测性。笔者认为,能源和相关的环境影响可能制约中国的经济增长。根据国际经验,本文揭示了有助于中国实现可持续增长的“不可见的”市场信号和“可见”的政府政策。本文还对亚洲开发银行(亚行)可以提供援助的领域做了简要的介绍。[编者按]  相似文献   
92.
A method was developed for sulfosulfuron [(1-(2-ethylsulfonylimidazo [1,2-a] pyridin-3-ylsulfonyl)-3-(4,6-dimethoxy pyrimidin-2yl)] and its three major metabolites by HPLC utilizing photodiode array detector. The method makes use of Lichrosphere RP-8 column and acetonitrile:water:orthophosphoric acid (80:20:0.1 v/v/v) as mobile phase at a flow rate of 1 ml min(-1). Using these condition sulfosulfuron, and compounds II, III and IV were resolved with distinct Rt of 2.088, 2.216, 2.302 and 2.476 minutes, respectively. Sulfosulfuron residues were analysed in soil, wheat grain and straw samples by extracting with a mixture of acetonitrile and 2 M ammonium carbonate (100 ml, 9:1, v/v) using horizontal shaker for soil and Soxhlet apparatus for wheat grain and straw samples. The extracts were cleaned up by partitioning with dichloromethane in case of soil and hexane followed by dichloromethane for plant samples. The percent recovery ranged between 71 to 75.2 for soil and 70.8 to 74.7 for plant samples. The limit of determination of sulfosulfuron was 0.25 microg g(-1).  相似文献   
93.
The industrial waste effluents from two industries of Durgapur have been traced along the course of Tamla Nalah at selected sites up to its confluence with the Damodar river and downstream. There are evidences of contamination of the river with toxic pollutants—ammonia, phenol, cyanide, sulphide, and trace mercury from Tamla Nalah. The upstream river water (Durgapur barrage), which is believed to be fairly pure, is actually not much better than the downstream river water. Monitoring data for about a year are presented and discussed.  相似文献   
94.
95.
Sources of submicron aerosol during fog-dominated wintertime at Kanpur   总被引:1,自引:0,他引:1  
The main objective of this atmospheric study was to determine the major sources of PM1 (particles having aerodynamic diameter <1.0 μm) within and near the city of Kanpur, in the Indo-Gangetic Plain. Day and night, 10 h long each, filter-based aerosol samples were collected for 4 months (November 2009 to February 2010) throughout the winter season. These samples were subjected to gravimetric and quantitative chemical analyses for determining water-soluble ions (NH4 +, F?, Cl?, NO3 ?, and SO4 2?) using an ion chromatograph and trace elements using an inductively coupled plasma–optical emission spectrometer. The mean PM1 mass concentrations were recorded as 114?±?71 μg/m3 (day) and 143?±?86 μg/m3 (night), respectively. A significantly higher diurnal contribution of ions (NH4 +, F?, Cl?, NO3 ?, and SO4 2?) in PM1 mass was observed during the fog-affected days and nights throughout the winter season, for which the average values were recorded as 38.09?±?13.39 % (day) and 34.98?±?12.59 % (night), respectively, of the total PM1 mass. This chemical dataset was then used in a source-receptor model, UNMIX, and the model results are described in detail. UNMIX provided a maximum number of five source factors, including crustal material, composite vehicle, secondary aerosol, coal combustion, and iron/steel production and metallurgical industries, as the dominant air pollution sources for this study.  相似文献   
96.
In the peri-urban areas of central India, sewage water is a valuable resource for agricultural production. In this study, impact of domestic sewage water irrigation for 5 years on Vertisol with no previous history of sewage irrigation was investigated in an ongoing field experiment at Bhopal (India) under subtropical monsoon type climate. The wheat (Triticum aestivum) crop was grown during post-rainy winter season with 30 cm of irrigation (groundwater or sewage water) and four nutrient treatments (T1, 0; T2, 100%; T3, 50%; and T4, 50% of general recommended doses of NPK + FYM at 10 Mg/ha). Results showed that sewage irrigation of about 150 cm over a period of 5 years resulted significant increases in salinity as well as available fractions of N, P, K, and micronutrients, viz., Zn, Fe, and Mn in soils. Carbon and phosphorus applied through sewage water were accumulated more in subsoil layer compared to topmost plough layer. Soil microbiological activity, as indicated by soil respiration, microbial biomass C, as well as dehydrogenase enzyme activity was higher in sewage water-irrigated soils. There was also significant increase in fungal and actinomycetes as well as total coliform population in such soils. Nutrients supplied through sewage water were not able to raise the productivity of wheat to the level that obtained through fertilizers at the recommended level which indicated that additional nutrients through fertilizers are required to obtain higher productivity of wheat under sewage farming. Protein and Zn content in wheat grains were more when the crop was grown with sewage irrigation. Overall results show that except for increase in coliform population, short duration (5 years) of municipal sewage water irrigation did not have any appreciable harmful effect on soil quality as well as crop productivity; rather, it proved beneficial in improving soil fertility, wheat productivity, and produce quality.  相似文献   
97.
ABSTRACT

To understand the temporal variations of the physicochemical characteristics of the Bhagirathi-Hooghly River (BHR), three locations representing three districts of West Bengal were selected. The material fluxes from 34 drains during pre-monsoon season was quantified. The analysis of variance (ANOVA) revealed that no significant spatial variations were observed for the physicochemical parameters, whereas seasonal variations were significant. The mean discharge was found to be highest (247.2?×?103?m3?d?1) in the midstream drains. Highest mean concentrations of dissolved oxygen (DO) (7.35?mg?L?1) and nitrate (0.81?mg?L ?1) were observed during the post-monsoon season followed by the monsoon and pre-monsoon. According to the BIS, WHO and the European standard of water quality (pH, 6.5–8.5; Nitrate, 0–2.5?mg?L?1;DO, ≥5?mg?L?1), the results of the respective parameters revealed the BHR system is maintained at high to good water quality, meaning that the BHR system is slightly altered from its pristine environment. The mean concentrations of biological and chemical oxygen demands were found to be high during the monsoon season, revealing that a large quantity of refractory organic matter is transported to the eastern Bay of Bengal from the Ganges.  相似文献   
98.
This study investigated dioxins and dioxin-like polychlorinated biphenyls in gasses emitted from waste incinerators and thermal processes in central and western parts of India. The concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/DFs) ranged from 0.0070 to 26.8140 ng toxicity equivalent (TEQ)/Nm3, and those of dioxin-like polychlorinated biphenyls (PCBs) ranged from 0.0001?×?10?1 to 0.0295 ng TEQ/Nm3. The characteristics of mean PCDD/F I-TEQ concentration and congener profiles were studied over all the samples of air. In particular, a pattern consisting of a low proportion of dioxin-like PCBs and high proportion of PCDDs/DFs was common for all the samples from incinerators and high-temperature processes.  相似文献   
99.
This paper evaluates possible long-range source contributions to the PM10 profile of Istanbul, Turkey. A novel method for classifying PM10 episodic events resulting from long-range transport, as opposed to local ones, was implemented. Hourly PM10 mass concentrations from ten stations distributed throughout Istanbul during the year 2008 were used for this purpose. Hourly backward trajectories for the arrival of air masses to the center of Istanbul for the year 2008 were calculated using the HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory) model. Significant episodes from these backward trajectories were selected and employed in Potential Source Contribution Function (PSCF) analysis to estimate the possible contribution of long-range PM10 transport (LRPMT) to observed PM10 concentrations. The PSCF results showed significant seasonal variations. Based on the results obtained, PM10 concentrations observed in Istanbul during summer and autumn are not heavily affected by LRPMT. Mediterranean countries, especially those of the central part of northern Africa (northern Algeria and Libya) are the most significant potential PM10 contributors to Istanbul's atmosphere during springtime. During winter, Balkan countries, including the Aegean part of Turkey, Greece, Bulgaria, Serbia, and Croatia, as well as northern Italy, eastern France, southern Germany, Austria and the eastern part of Russia, were the most important LRPMT source regions for high PSCF values.  相似文献   
100.
This research introduces a proactive methodology for accident prevention, called Continuous Safety Sampling Methodology, by utilizing the principles of work sampling and control charting. Sampling is performed to observe the occurrence of conditions that may become hazardous in a given system. These conditions, known as dendritics, may become hazards and could result in an accident or occupational disease. Continuous Safety Sampling Methodology performs a random sampling for the occurrence of these dendritics. The collected data are then used to generate a control chart. Based on the pattern of the control chart, a system “under control” is not disturbed whereas a system “out of control” is investigated for potential conditions becoming hazardous. Appropriate steps are then taken to eliminate or control these conditions to maintain a desired safe system.  相似文献   
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