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田野上的希望——解决农业科技断层问题刻不容缓
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作者 范青保 《农村经济与技术》 2003年第1期12-13,共2页
这几年,经过实施农业和农村经济结构战略性调整,我国农业已经闯出了一条科学种田、规模经营的路子,农业效益有了明显提高,农村出现了生机,农业大有希望。但是,由于我国地域辽阔,发展并不平衡,在不少地方农业发展不能与时俱进,普遍存在... 这几年,经过实施农业和农村经济结构战略性调整,我国农业已经闯出了一条科学种田、规模经营的路子,农业效益有了明显提高,农村出现了生机,农业大有希望。但是,由于我国地域辽阔,发展并不平衡,在不少地方农业发展不能与时俱进,普遍存在着一个非常突出的战略性问题,即在贯彻“以农业为基础”方针,推进科技进步,实现“科技兴农”战略的过程中。 展开更多
关键词 科学技术 对策 农业 科技断层
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变“断层”为契机 全面规划农业科研改革
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作者 王淳 《农业科技管理》 北大核心 1992年第4期51-52,共2页
关键词 农业科研单位 科技人员年龄断层 农业科技体制改革
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Development of advanced electron tomography in materials science based on TEM and STEM 被引量:5
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作者 李茂华 杨延清 +4 位作者 黄斌 罗贤 张伟 韩明 汝继刚 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第10期3031-3050,共20页
The recent developments of electron tomography(ET) based on transmission electron microscopy(TEM) and scanning transmission electron microscopy(STEM) in the field of materials science were introduced. The variou... The recent developments of electron tomography(ET) based on transmission electron microscopy(TEM) and scanning transmission electron microscopy(STEM) in the field of materials science were introduced. The various types of ET based on TEM as well as STEM were described in detail, which included bright-field(BF)-TEM tomography, dark-field(DF)-TEM tomography, weak-beam dark-field(WBDF)-TEM tomography, annular dark-field(ADF)-TEM tomography, energy-filtered transmission electron microscopy(EFTEM) tomography, high-angle annular dark-field(HAADF)-STEM tomography, ADF-STEM tomography, incoherent bright field(IBF)-STEM tomography, electron energy loss spectroscopy(EELS)-STEM tomography and X-ray energy dispersive spectrometry(XEDS)-STEM tomography, and so on. The optimized tilt series such as dual-axis tilt tomography, on-axis tilt tomography, conical tilt tomography and equally-sloped tomography(EST) were reported. The advanced reconstruction algorithms, such as discrete algebraic reconstruction technique(DART), compressed sensing(CS) algorithm and EST were overviewed. At last, the development tendency of ET in materials science was presented. 展开更多
关键词 electron tomography materials science transmission electron microscopy scanning transmission electron microscopy
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