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491.
储气井是一种压力容器,也是地下压力容器的典型代表。由于开发储气井的理念来源于油气井,因此储气井具有常规压力容器所不具备的特性并存在很多先天不足。文章针对储气井的现状,剖析了储气井在材料、设计、制造、检验检测等各环节存在的问题,并对储气井的健康发展提出了改进建议。 相似文献
492.
产业协同发展与区域合作是经济社会发展的两大主旋律,区域产业的协同程度直接决定了经济社会发展的效率与质量.在湘南承接产业转移示范区建设与城乡统筹发展的大背景下,如何促进湖湘南三市产业协同发展与区域合作是我们面临的一个重大课题.本文分析大湘南示范区三市区域差异的基础上,探讨大湘南示范区三市区域合作的可行性,最后提出了促进湘南三市产业协同发展与区域合作的战略思路与对策.表7,参5. 相似文献
493.
Optimization of regional hazardous waste management systems: an improved formulation 总被引:1,自引:0,他引:1
The planning and design of regional hazardous waste management system (RHWMS) involves selection of treatment and disposal facilities, allocation of hazardous wastes and waste residues from generator to the treatment and disposal sites and selection of the transportation routes. An improved formulation based upon multi-objective integer programming approach is presented to arrive at the optimal configuration of RHWMS components. This formulation addresses important practical issues like unique characteristics of the hazardous wastes reflecting on waste–waste and waste–technology compatibility. A utility function approach is presented to integrate both cost and risk related objectives. An illustrative case example is presented to demonstrate the usefulness of the improved formulation as a tool which can be used by environmental planning agencies in regional planning for hazardous waste management. 相似文献
494.
南京某燃煤电厂汞的排放特点及分布特征 总被引:3,自引:0,他引:3
选择南京某燃煤电厂330 MW机组,对煤、炉渣、粉煤灰、烟尘、石灰石、石膏和烟气中的汞取样测量,探讨煤中汞在燃烧过程中的变化情况,并进一步分析汞的排放特点及分布特征。指出,煤经燃煤锅炉炉内高温燃烧后,炉渣中的汞对环境影响不明显;粉煤灰、烟尘中的汞存在富集现象,且随着粒径变细,富集程度加剧;燃煤锅炉燃烧后,随石膏排放的汞占比较大,应采取相应的防治措施。 相似文献
495.
珠海市大气污染时空分布特征及成因分析 总被引:2,自引:0,他引:2
应用统计方法分析了珠海市的大气污染物SO2、NO2、PM10浓度的时空分布特征.针对珠海市的污染源分布格局和当地的气象条件对上述污染物时空分布特征的成因进行了分析.研究表明,珠海市的污染物浓度空间分布较为均匀,没有显著的空间变化梯度出现;但在时间分布方面明显存在着冬春高、夏秋低的季节性差异,并受区域环境的影响较大.相关分析表明,珠海市单点源污染比例大的污染源分布格局以及典型的季风气候是造成如上污染特征的主要原因,此外珠海市的经济产业结构也存在着一定的影响. 相似文献
496.
Farooq S Hashmi I Qazi IA Qaiser S Rasheed S 《Environmental monitoring and assessment》2008,140(1-3):339-347
The present study was undertaken to examine the drinking water quality of Rawal Treatment Plant, Rawalpindi and its distribution
network by collecting samples from eight different locations. The aim was to determine potential relationship between the
presence of microorganisms and chlorine residual in the distribution network. Quantification of chlorine residual, turbidity,
standard plate count (SPC), fecal and total coliforms by Most Probable Number (MPN) was performed. Three different forms of chlorine were measured at each sampling station such
as free chlorine, residual chlorine, chloramines and total chlorine residual. A critical evaluation of data presented indicated
that pH generally ranged from 7.02–7.30; turbidity varied from 0.34–2.79 NTU; conductivity fluctuated from 359–374 μS/cm;
and TDS values were found to be ranging between 180–187 mg/l. Station # 7 was found to be most contaminated. The value of total chlorine was found to be 0.86 to1.7 mg/l at Station # 3 and 6, respectively. Highest standard plate count was 62 CFU/ml at Station # 7. Total
coliforms were less than 1.1 MPN/100 ml at almost most of the stations except at Station # 3 where it was found to be greater than 23.0 MPN /100 ml. Overall aim of this study is to create awareness about contamination
of drinking water in the water distribution networks and to make recommendations to provincial agencies such as EPA, CDA and
WASA that regular monitoring should be carried out to ensure that the chlorine residual is available at consumer end. 相似文献
497.
The phosphorus fractions and adsorption characteristics of seven floodplain sediment samples collected in the lower reaches
of China’s Hanjiang River were studied. Most phosphorus fractions showed a marked downstream increase in response to point-source
inputs from urban areas. Total phosphorus (TP) contents in the sediments ranged from 603.68 to 945.25 mg.kg−1. Inorganic phosphorus (IP) was the major component of TP, and calcium-bound phosphorus (Ca–P) was the major fraction of IP.
The distribution characteristics of the phosphorus contents were affected by sediment grain size and hydrodynamic conditions.
The maximum phosphorus adsorption capacities (Q
max) and the half-saturation concentration (k) were obtained using an improved Langmuir model. Native adsorbed exchangeable phosphorus content (w
NAP) and the zero-equilibrium phosphorus concentration value (c
EPC0) were subsequently calculated. The effects of sediment grain size, temperature, and disturbance on the phosphorus adsorption
isotherms were also studied. The results showed that phosphorus adsorption on floodplain sediments was primarily chemisorption;
the particle concentration effect played a more important role at a disturbance intensity of 150 r.min−1 (on a shaker table) than at 100 r.min−1. 相似文献
498.
499.
The agricultural and industrial development of small cities is the primary environmental management strategy employed to make full use of extra labor in the rural areas of China. The ecological and economic consequences of this development strategy will affect over 100 million people and change the organization of the Chinese landscape. In this study, we examined the agricultural development of Shunde, a small city in Guangdong Province, over the period 1978 until 2000. Our analysis of the ecological and economic dynamics of the agricultural system revealed the dominant role of labor in the intensification of agricultural production, even though the use of fuels, fertilizers and machines also increased during this time. The Shunde agricultural system was examined from both biophysical or donor-based and human utility or receiver-based perspectives, using emergy and economic methods, respectively. After 22 years of urbanization, the Shunde agricultural system was still able to fill 96% of the local demand for agricultural products using only 6% of its total yield compared to using 14% of the total yield in 1978. Aquaculture developed quickly during the study period as grain production decreased. In 2000, the production of fish, pork, and vegetables accounted for 92% of the total emergy output of the system; however, the emergy buying power of the money received in exchange was lower than the emergy contained in the products exported. The excess emergy exported is the basis for a high quality diet delivered to city dwellers at a relatively low price. In the 1980s, the productivity of both land and labor increased; but after 1992 the productivity of labor decreased, causing the efficiency of the whole agricultural system to decrease. We recommend that processing plants be established for the main agricultural products of Shunde to decrease the emergy loss in trading and to increase employment. The effect of including monetized ecosystem services in the balance between the emergy delivered to the markets in agricultural products and the emergy buying power of the money received was to decrease the emergy gained by the Shunde agricultural system. 相似文献
500.
An environmental sustainability based budget allocation system for regional water quality management
A budget allocation system for regional water quality management to achieve environmental sustainability was developed in this study to assist a local authority with making appropriate budget allocations for improving Regional Water Environmental Sustainability (RWES) in an efficient manner. The system consists of visions and goals, RWES indicators, and an analysis of budget allocation versus RWES. Visions and goals define task priorities for improving water environmental sustainability. Indicators are used to measure the progress of related tasks toward RWES goals. These indicators are classified by the Driving Force-State-Response (DSR) framework to facilitate the analysis of relationships among indicators. Linkages between budget allocation and indicators are also analyzed, and the result is used to assess whether the available budget is allocated properly to raise the RWES. The applicability of the system is demonstrated by a case study involving a local environmental protection authority. 相似文献