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关于对目前石油钻井技术的研究和探讨
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作者 吴志怀 丁海军 宋智 《中国化工贸易》 2012年第8期122-122,共1页
石油,是具有不可再生的珍贵属性,而且在国民经济的发展中起着举足轻重的作用,因此被形象的称作”黑色黄金”,石油在工业生产中占据着不可缺少的重要地位,目前,我国对石油的依赖程度排世界第二,由于我国是一个石油资源极其贫乏的... 石油,是具有不可再生的珍贵属性,而且在国民经济的发展中起着举足轻重的作用,因此被形象的称作”黑色黄金”,石油在工业生产中占据着不可缺少的重要地位,目前,我国对石油的依赖程度排世界第二,由于我国是一个石油资源极其贫乏的国家,所以在工业生产中受到了很多限制。面对险峻的国情,如何转变这种形势则变的尤为重要,而最主要的应该是提高石油钻井技术,使开发利用达到最优。本论文对我国目前的石油钻井技术进行了简单的研究和探讨,总结出以下几点结论。 展开更多
关键词 石油钻井技术 开发种类 勘探需要
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Historical Evolution of Mariculture in China During Past 40 Years and Its Impacts on Eco-environment 被引量:4
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作者 LIANG Yinxiu CHENG Xianwei +4 位作者 ZHU Hui Brian SHUTES YAN Baixing ZHOU Qingwei YU Xiangfei 《Chinese Geographical Science》 SCIE CSCD 2018年第3期363-373,共11页
The rapid development of mariculture in China in recent decades has satisfied people's demand of seafood, and has made a great contribution to economic development. However, mariculture has also caused some negati... The rapid development of mariculture in China in recent decades has satisfied people's demand of seafood, and has made a great contribution to economic development. However, mariculture has also caused some negative impacts on the eco-environment. By statistically analyzing national data(as well as data for four main provinces) regarding the mariculture area and cultivation species in China since reform and opening up, the historical evolution of mariculture during the past 40 years was analyzed, the driving factors related to policy, market and technology innovation were discussed, and the potential impacts of mariculture on the coastal eco-environment were also illustrated. The statistical results indicated that the maricultural area increased radically during the past 40 years, from 1979(116.47 × 10~3 ha) to 2012(2205.65 × 10~3 ha), with an increase of nearly 20-fold. Shandong Province represented the fastest-growing region, with an increase of 31-fold. Moreover, the cultivated species had gradually become diversified. Initially, shellfish and algae were major species, and then it developed to various species including fish, and currently shellfish and crustaceans were the major species. The development of mariculture was driven by government policies, market economy and technology innovation. Rapid development of mariculture also caused significantly adverse impacts on the eco-environment of the coastal regions. For example, the sea reclamation for mariculture decreased the area and function of coastal wetlands and the contaminants originating from mariculture destroyed the coastal aquatic environment. Fortunately, the implementation of ‘13 th Five-Year Fisheries Planning' is expected to help both improve the seafood quality and reduce the contamination in coastal aquatic environment. This current study will provide reference for management and structure adjustment of mariculture in the future. 展开更多
关键词 mariculture reclamation coastal wetlands aquatic environment pollution
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临江市野生食用菌资源调查
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作者 图力古尔 《吉林蔬菜》 1998年第4期22-22,共1页
临江市位于长白山腹地。主要植被类型为红松(Pinuskoraiensis)、油松(Pinustabulaeformis)、落叶松(Larixolgensis)、冷杉(Abiesnephrolepis)、东北红豆杉(T... 临江市位于长白山腹地。主要植被类型为红松(Pinuskoraiensis)、油松(Pinustabulaeformis)、落叶松(Larixolgensis)、冷杉(Abiesnephrolepis)、东北红豆杉(Taxuscuspidata)等针叶... 展开更多
关键词 菌类 野生食用菌 资源调查 开发种类
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R & D Activities on Urban Forestry in the Philippines 被引量:1
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作者 Leila C. America 《Chinese Forestry Science and Technology》 2004年第3期32-38,共7页
This paper highlights the research and development activities being done on urban forestry in the Philippines. The rolethat R & Dplaysin urban forestryislikewise discussed in theintroduction. Recommended tree spec... This paper highlights the research and development activities being done on urban forestry in the Philippines. The rolethat R & Dplaysin urban forestryislikewise discussed in theintroduction. Recommended tree species for urban planting are presented including their characteristics and distribution. Researches related to urban forestry being conducted are listed with a short description of each project. Development activities on urban forestry are likewise discussed. Finally, recommended R &D agenda and researchable areasbased on the Philippine Agenda 21 and the Department of Environmentand NaturalResources(DENR) R & D Framework are presented. 展开更多
关键词 urban forestry tree species R & D the Philippines
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