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明清医学专科目录研究
作者: 张晓丽   来源: 安徽大学 年份: 2010 文献类型 : 学位论文 关键词: 专科目录   医学   明清   文献价值  
描述: medical books. The medical literatures was very abundance in ancient China ,it were noted in the synthesis ogue.
全文:,现存明清时期较有价值的医学专科目录有四部,即明代殷仲春著《医藏目录》清代曹禾著《医学读书志》,凌奂著《医学薪传》,丁福著《历代医学书目提要》,其分类体系与体制结构具有独到的目录学价值,本文利用中医
基于~(137)Cs技术的中国北方农牧交错带土壤侵蚀研究
作者: 姜洪涛   来源: 内蒙古师范大学 年份: 2010 文献类型 : 学位论文 关键词: 土壤侵蚀   农牧交错带   ~Cs   示踪  
描述: ttention, but also agriculture and eco-environmental sustainable development important problems. Farming-pastoral Transitional zone in north China, as our county returning farmland to forest and returning cropping land to grassland are the focus areas, natural environment and socio-economic conditions shown a clear transition characterized by the transition zone of the interpenetration and staggered distribution of agriculture and animal husbandry, which is curbing desertification important ecological barrier, but also ecologically fragile belts.
全文:样品,用美国ORTEC公司生产的型号为GMX50P4N型同轴型高锗γ探测器探测在不同土地利用方式下的土壤样品中的~(137)Cs含量,测得各土地利用类型中~(137)Cs含量从高到低的顺序为:平草地
中国传统水车研究
作者: 方立松   来源: 南京农业大学 年份: 2010 文献类型 : 学位论文 关键词: 传统水车   农具史   农田灌溉  
描述: large-scale farming tool that can water continuously from the ground-surface water in the rivers, lakes, or pools, and is mainly applied to lifting water to the high ground or drain water in the low-lying farmland. Due to the reason that the traditional
全文:领域,而且在济漕运、沿海制盐等非农业方面也发挥了重要的作用。传统水车虽功效显著,但在实际应用中灌溉能力、灌溉效率存有差异。总体上,无论从能力还是效率上,筒车为最高,其次是风力翻车和畜力翻车,再次是脚踏
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