农村非国有企业与农村经济增长——以甘肃省为例     

宗鑫  张伟 《许昌学院学报》2011,30(4):118-120

通过对主要经济指标的回归分析可知,农村非国有企业转移或吸纳农村剩余劳动力数量对农村经济总收入影响显著,农村非国有企业从业人员的增加对企业总产值的影响显著。可见,农村剩余劳动力的流动,不仅会促进农村经济增长,增加农民收入,而且对于农村非国有企业本身而言,也有益于其成长和发展。因此,须充分实现农村剩余劳动力的流动,大力发展农村非国有企业。  相似文献   

荷兰大学教师发展研究轨迹探析     

吴薇 《复旦教育论坛》2011,9(5)

20世纪60年代以来,荷兰的大学教师发展研究顺应了其教师教育研究的发展,走过了一条从稚嫩到相对成熟的发展之路,至今仍呈现出国际化水平不断提升的良好发展态势。本文对荷兰教师教育研究的历程作简要的回顾,在此基础上,以荷兰跨校教育研究中心和莱顿大学教师教育研究院为例,具体分析该国以研究促发展的大学教师发展研究的内容与特点。  相似文献   

国内外政府数据开发利用的进展及对我国的政策建议          下载免费PDF全文

宋卿清  曲婉  冯海红 《中国科学院院刊》2020,35(6):742-750

近年来,大数据浪潮兴起,大数据产业保持高速发展态势,大数据应用推进势头良好。政府数据作为价值密度高、涉足广度宽的数据资源,已成为各国争相创新开发的重要资产。但是长期以来,关于政府数据开发利用的理论研究却被忽视,如何科学有效地进行政府数据开发和利用已成为当前需要迫切关注的问题。文章系统总结了当前主要发达国家政府数据开发利用的政策措施和探索实践,以及通过梳理分析我国政府数据开发利用的政策体系和发展现状,尝试构建政府数据开发利用的过程机制模型,并提出:加强顶层立法,落实制度保障;扩大数据来源,提升数据质量;统一汇聚开放,深化行业应用;确立认证许可,明晰授权机制;创新开发模式,明确收益分配;推动试点先行,探索可行经验;强化技术支撑,保障数据安全等政策建议,以期为进一步推动政府数据开发利用提供决策参考。  相似文献   

冰冻圈微生物：机遇与挑战          下载免费PDF全文

陈拓  张威  刘光琇  李师翁 《中国科学院院刊》2020,35(4):434-442

近年来,冰冻圈微生物的研究受到广泛重视。冰冻圈的低温和严酷的生存条件,选择了具有独特适应性和多样性的微生物,这些微生物是地球生命系统和生物多样性的独特组分。冰冻圈微生物大多为冷适应微生物;其中,有许多新微生物类群,是极其重要的物种和基因资源。嗜冷微生物是揭示生物冷适应机制的模式生物,其细胞及细胞组分在低温生物工艺上显示出巨大的应用价值。冰冻圈中也封存着一些古老的未知致病性微生物。冰冻圈是地球上对气候变化最为敏感的圈层,地球的升温正加速冰冻圈的退化和消融,冰冻圈微生物赖以生存的生境正在消失,且伴随着微生物的释放。这些微生物的释放可能是人类面临的不可预知的威胁。因此,亟待开展冰冻圈微生物调查与研究,探讨其对全球变化的响应及其适应机制。  相似文献   

“互联网+”时代背景下“科研思路与方法”教学模式探讨     

邓思思  陈江  张蕖  陈书  朱旭  魏歆然  魏高文  宋祯彦 《科教文汇》2020,(13):87-88

当前,国家对大学本科的教育愈发重视,提出了多种教改方案。面对“互联网+”快速发展的形势,文章分析了“互联网+”时代背景下“科研思路与方法”新型教学模式的优势以及如何高效率地构建。通过教师、学生、互联网三者协调配合以及师生的线上互动交流和讨论,可以充分调动学生独立思考、自主学习的积极性,同时增加了教学趣味性,提高了教学质量。  相似文献   

Development of a space cold atom clock     

Wei Ren  Tang Li  Qiuzhi Qu  Bin Wang  Lin Li  Desheng Lü  Weibiao Chen  Liang Liu 《国家科学评论(英文版)》2020,7(12):1828

Atomic clocks with cold atoms play important roles in the field of fundamental physics as well as primary frequency standards. Operating such cold atom clocks in space paves the way for further exploration in fundamental physics, for example dark matter and general relativity. We developed a space cold atom clock (SCAC), which was launched into orbit with the Space Lab TG-2 in 2016. Before it deorbited with TG-2 in 2019, the SCAC had been working continuously for almost 3 years. During the period in orbit, many scientific experiments and engineering tests were performed. In this article, we summarize the principle, development and in-orbit results. These works provide the basis for construction of a space-borne time-frequency system in deep space.  相似文献   

Equatorial aurora: the aurora-like airglow in the negative magnetic anomaly     

Fei He  Yong Wei  Weixing Wan 《国家科学评论(英文版)》2020,7(10):1606

The most fantastic optical phenomena in the Earth''s upper atmosphere are the auroras. They are highly informative indicators of solar activity, geomagnetic activity, upper atmospheric structures and dynamics, and magnetospheric energetic particles. An area where the geomagnetic field differs significantly from the expected symmetric dipole, such as at the South Atlantic Anomaly, where the magnetic field intensity is low, gives rise to stronger precipitation of energetic particles into the upper atmosphere. Impact excitation and the subsequent airglow emissions exhibit aurora-like dynamic signatures. Nomenclatures of nonpolar aurora or equatorial auroras are similar to those used with the polar auroras owing to their similar excitation mechanisms. This paper provides an overview of the knowledge and the challenges concerning auroral activity at the South Atlantic Anomaly, or more generally, at the negative magnetic anomaly. We emphasize systematic investigation of the equatorial auroras to reveal the temporal and spatial evolution of the magnetic anomaly and the behaviour of energetic particles in near-Earth space.  相似文献   

Olivine-norite rock detected by the lunar rover Yutu-2 likely crystallized from the SPA-impact melt pool     

Honglei Lin  Zhiping He  Wei Yang  Yangting Lin  Rui Xu  Chi Zhang  Meng-Hua Zhu  Rui Chang  Jinhai Zhang  Chunlai Li  Hongyu Lin  Yang Liu  Sheng Gou  Yong Wei  Sen Hu  Changbin Xue  Jianfeng Yang  Jie Zhong  Xiaohui Fu  Weixing Wan  Yongliao Zou 《国家科学评论(英文版)》2020,7(5):913

Chang’E-4 landed in the South Pole-Aitken (SPA) basin, providing a unique chance to probe the composition of the lunar interior. Its landing site is located on ejecta strips in Von Kármán crater that possibly originate from the neighboring Finsen crater. A surface rock and the lunar regolith at 10 sites along the rover Yutu-2 track were measured by the onboard Visible and Near-Infrared Imaging Spectrometer in the first three lunar days of mission operations. In situ spectra of the regolith have peak band positions at 1 and 2 μm, similar to the spectral data of Finsen ejecta from the Moon Mineralogy Mapper, which confirms that the regolith''s composition of the landing area is mostly similar to that of Finsen ejecta. The rock spectrum shows similar band peak positions, but stronger absorptions, suggesting relatively fresh exposure. The rock may consist of 38.1 ± 5.4% low-Ca pyroxene, 13.9 ± 5.1% olivine and 48.0 ± 3.1% plagioclase, referred to as olivine-norite. The plagioclase-abundant and olivine-poor modal composition of the rock is inconsistent with the origin of the mantle, but representative of the lunar lower crust. Alternatively, the rock crystallized from the impact-derived melt pool formed by the SPA-impact event via mixing the lunar crust and mantle materials. This scenario is consistent with fast-cooling thermal conditions of a shallow melt pool, indicated by the fine to medium-sized texture (<3 mm) of the rock and the SPA-impact melting model [Icarus 2012; 220: 730–43].  相似文献   

The essential mass transfer step in hierarchical/nano zeolite: surface diffusion     

Jian Zhou  Wei Fan  Yangdong Wang  Zaiku Xie 《国家科学评论(英文版)》2020,7(11):1630

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知識産權基本法要慎行     

韋之  王一璠 《中国专利与商标》2020,(2):100-104

近來,有業内人士建議儘快制定知識産權的基本法,對知識産權的共性問題進行規制。"知識産權基本法"並不是一個新概念,在十幾年前就有學者提出。2018年在《國家知識産權戰略綱要》實施10週年評估工作中,有關部門啓動了知識産權基本法的研究起草工作,據稱目前已形成專家建議稿。我們認爲,在推動制定知識産權基本法之前,以下兩個問題尚需慎重對待。  相似文献