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1.
1Introduction[1 ] China’spetrochemicalindustryemergedin 1 96 0s.Thees tablishmentofChinaPetrochemicalCorporation (SINOPEC)in 1 983indicatesaneweraofrapiddevelopmentofChina’spetrochemicalindustry .Duringthe 1 5yearsfrom 1 983to1 998,7large scaleethylene basedpetrochemicalcomplexeswereerectedinYanshanPetrochemicalCompany,DaqingPetrochemicalCompany,QiluPetrochemicalCompany,YangziPetrochemicalCompany ,ShanghaiPetrochemicalCompany ,MaomingPetrochemicalCompanyandJilinPetro chemicalCo…  相似文献   

2.
Australia is one of the world leaders in water management. The country meets the challenge of water shortage with established integrated water management in which rainwater is taken as a too precious resource to be just drained off. In Australia, rainwater is extensively harvested and polished to provide cheaper supply for potable and non-potable domestic uses, irrigation, landscaping, refilling aquifers and other uses. Implementing dual management over the quantity and quality of storm water and practicing water sensitive urban design (WSUD) in urban areas effectively control non-point-source pollution of waterways by pollutants carried with runoffs, reduce the discharge of rainwater and thus protect properties and lives from damage by floods. These achievements are attributed to constant reinforcement by govenments from federal to local levels in policy, financial, legal and educational aspects, and also to the lasting efforts of professional communities and water industry in developing requisite techniques, demonstrating the benefits and fostering public credence of rainwater reuse. The successful rainwater management practices in Australia suggest rainwater harvesting can be a complimentary means for the South-to-North Water Transfer Scheme to solve the water shortage in China’s northern regions, and thus release to a degree the pressure on the Yangtze water resources. Best management practices of rainwater can be an effective controlling strategy for flooding and non-point-source water pollution of waterways. Such in-site source control initiatives have particular significance to protecting slow waterways of weak self-purification ability, like the Three Gorges Reservior.  相似文献   

3.
Anthropogenic factors affect biodiversity and have led to the contraction or extinction of animal populations worldwide.Here,we use historical demographic data,spanning the past 300 years,to show that a rapid distributional contraction of giant pandas took place during the 18th and 19th centuries alongside the increase in human population.Land-use also underwent a significant change across the areas where giant pandas were found because of government agricultural policy and the introduction of new crops.The impact of social development on giant pandas includes habitat loss and fragmentation,and range reductions.Our findings would facilitate the design of effective conservation strategies that seek to conserve and increase current habitats of this iconic species,especially in areas that our analysis has identified as places where pandas have suffered from high human pressure.  相似文献   

4.
The white paper document titled“China’s Space Activities”,released in November2000by the Information Office of the State Council,represents the first time for China to fully,systematically and publicly introduce to the world China’s space development strategy and concerned policies.Its release is a milestone event in the country’s space history,bearing great importance and profound influence to its future space efforts.The paper here describes the shaping processes of some important new ideas and concepts,including the connotative meaning of“space activities in a broad sense”and the roles and positions of different sectors in such activities.It also briefly discusses related policies concerning the country’s space development and short term concepts and plans on its civil space activities.  相似文献   

5.
To deal with the exploitation difficulties of gas fields in Northeast Sichuan with deep marine strata, after researching the relative standards domestic and abroad extensively, summarizing and promoting the successful experiences and failure lessons of project construction technology application scientifically, Sinopec has established an integrated technical standard system for the exploration and development of ultra deep and high sour gas fields. The system consists of 51 enterprise standards and covers 7 professions including geophysical prospecting, drilling, drilling log, well logging, gas formation test and production, sour gas gathering and transferring system, and HSE (health,safety,environment). It guides and guarantees the safe, high-quality and high-efficiency project construction effectively by means of enhancing the engineering design criterion, recommending the data processing and interpretation methods, identifying the requirements of operation and field inspection and standardizing the application of technical equipments.  相似文献   

6.
Stable isotopes of water are widely used in scientific research to reconstruct paleoclimate and paleoenviron- ment variations[1―4]. Atmospheric water vapor plays a keyrole in the precipitation events. Therefore, the isotopic composition of atmospheric water vapor has a direct effect upon that of precipitation[5,6]. Observation of stable isotope variation of atmospheric water vapor has an important significance to indicate the moisture origins andmoisture transport in the study area. Based on …  相似文献   

7.
The effect of land use pattern on the heavy metals(HMs)distribution in soil profiles was investigated in Yixing City,China,for the four typical types of land utilization,i.e.vegetable fields on the plain,paddy fields,tea gardens on hilly lands and bamboo groves.The variance of HMs concentration in the depth of 0-15 cm,15-30 cm,30-60 cm of soil profiles was compared among the different tillage ages. Results showed there was a notable accumulation of Cd,Hg,Cu,Pb,Zn and Cr in the soil profiles of vegetable fields and paddy fields causing a pollution of Cu,Hg and Cd in some profiles,while no remarkable accumulation of HMs in the soil profiles of the tea gardens and bamboo groves was found. The accumulation extent of HMs in the soil profiles of the four kinds of land use followed a sequence of vegetable fields>paddy fields>tea gardens>bamboo groves.The accumulation of HMs was mainly due to the industry,transportation,other urban human activities,and intensive use of fertilizers and pesticides.The downward leaching of HMs was relatively remarkable in the soil profiles of vegetable fields. There was an accumulation in surface and subsurface layers for Cd,Hg,Pb,Zn in the soil profiles of paddy fields and tea gardens,and for Cd,Hg in those of bamboo groves.Serious pollution effects of Hg, Pb,and Zn have been shown in the soil of vegetable fields.All the four kinds of agricultural land are basically free from the pollution of the external sources of As and Ni.With the increase of tillage time, the soil of vegetable and paddy fields will face the potential risk of HMs pollution,which mainly comes from Hg,Cd and Cu,whereas that of tea gardens and bamboo groves faces a relatively small risk.  相似文献   

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It is worthy of studying the effect of water content in crude oil on tribological behavior of stator rubber, because the different water content would affect the swelling and wear of rubber. Compatibility of dewatered crude oil and water was observed after mixture of dewatered crude oil and water (called oilwater mixture) was mechanical stirred and statically placed. Static etching experiment of samples in oil-water mixture was performed using hanging patch test. Wetting contact angle of oil- water mixture on rubber surface was measured by contact angle meter. Tribological behavior of samples in mixture was measured using a ringonblock tester. The result shows that when the water content is less than 15 %, water can blend with dewatered crude oil, and oil-water separation happens when water content was more than 15 %. With the increasing of water content in crude oil, Wettability of mixture and swelling increment of samples decrease. The wear loss of sample increases after treated by swelling experiment, and FKM owns better wear resistance than NBR.  相似文献   

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