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本文对科技查新定义的演化进行了叙述,指出了科技查新的作用和意义,并结合实际工作体会,针对现阶段如何更好的完善科技查新工作提出了一些见解. 相似文献
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We study the four-body decays of neutral flavored mesons,including■,and■.These processes,which could be induced by a hypothetical doubly-charged scalar particle,do not conserve the lepton number.Assuming,as an example,that the mass of the doubly-charged particle is 1000 Ge V,and using the upper bounds of the couplings,we calculate the branching ratios of different channels.For■,and,it is of the order of 10~(-30),10~(-32)–10~(-29),and 10~(-33)–10~(-28),respectively.Based on the experimental results for the■channels,we also find the upper limit for the quantity■ 相似文献
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本文提出在科技查新课题量增长的趋势判断中引入定量预测的方法,对采用一次指数平滑预测方法进行了初步探讨,并对预测结果的产生进行分析。 相似文献
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由于量子受限效应,二维材料表现出很多三维材料所不具备的优异电学、光学、热学以及力学性能,为研究人员所关注.材料的优异物性离不开高质量材料的制备,超高真空环境可以减少杂质分子的污染与影响,提高二维材料的质量与性能.本文介绍基于超高真空环境的新型二维原子晶体材料的原位制备方法,包括利用分子束外延构筑新型二维材料、利用石墨烯插层构筑新型二维原子晶体材料异质结构以及利用扫描探针原位操纵构筑二维材料异质结构三大类.文章回顾利用这三类方法构筑的二维材料及其物理化学性质,比较三种方法各自的优势与局限性,对未来二维材料制备提供一定的指引. 相似文献
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科技创新人才评价机制是人才发展的指挥棒,对科技创新人才的发现、培育、使用和管理等具有重要意义。本文以科技创新人才的内涵为基础,通过查阅资料、问卷调查、实地调研等方法,深入探究安徽省科技创新人才评价现状和存在的问题,提出安徽省要加强科技创新人才评价的全流程管理,并从评价主体、评价标准、评价方式方法、评价结果管理等方面提出建议。 相似文献
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Intercalation of metals and silicon at the interface of epitaxial graphene and its substrates
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Intercalations of metals and silicon between epitaxial graphene and its substrates are reviewed. For metal intercala- tion, seven different metals have been successfully intercalated at the interface of graphene/Ru(O001) and form different intercalated structures. Meanwhile, graphene maintains its original high quality after the intercalation and shows features of weakened interaction with the substrate. For silicon intercalation, two systems, graphene on Ru(O001) and on Ir(l I 1), have been investigated. In both cases, graphene preserves its high quality and regains its original superlative properties after the silicon intercalation. More importantly, we demonstrate that thicker silicon layers can be intercalated at the interface, which allows the atomic control of the distance between graphene and the metal substrates. These results show the great potential of the intercalation method as a non-damaging approach to decouple epitaxial graphene from its substrates and even form a dielectric layer for future electronic applications. 相似文献
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PdTe_2,a member of layered transition metal dichalcogenides(TMDs),has aroused significant research interest due to the coexistence of superconductivity and type-II Dirac fermions.It provides a promising platform to explore the interplay between superconducting quasiparticles and Dirac fermions.Moreover,PdTe_2 has also been used as a substrate for monolayer antimonene growth.Here in this paper,we report the epitaxial growth of high quality PdTe_2 films on bilayer graphene/SiC(0001)by molecular beam epitaxy(MBE).Atomically thin films are characterized by scanning tunneling microscopy(STM),X-ray photoemission spectroscopy(XPS),low-energy electron diffraction(LEED),and Raman spectroscopy.The band structure of 6-layer PdTe_2 film is measured by angle-resolved photoemission spectroscopy(ARPES).Moreover,our air exposure experiments show excellent chemical stability of epitaxial PdTe_2 film.High-quality PdTe_2 films provide opportunities to build antimonene/PdTe_2 heterostructure in ultrahigh vacuum for future applications in electronic and optoelectronic nanodevices. 相似文献
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本文从城市现代物流发展规划的角度,针对目前各地现代物流园区存在"空置率"高的问题,从规划本身的思路和方法等方面分析了原因,指出现代物流园区的建设应该以满足不同阶段的现实市场需求为目标,避免大量投资、超前投资造成的风险,给出了对于现代物流发展规划中的政策制定的一些建议. 相似文献
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Majorana zero modes (MZMs) are Majorana-fermion-like quasiparticles existing in crystals or hybrid platforms with topologically non-trivial electronic structures. They obey non-Abelian braiding statistics and are considered promising to realize topological quantum computing. Discovery of MZM in the vortices of the iron-based superconductors (IBSs) has recently fueled the Majorana research in a way which not only removes the material barrier requiring construction of complicated hybrid artificial structures, but also enables observation of pure MZMs under higher temperatures. So far, MZMs have been observed in iron-based superconductors including FeTe0.55Se0.45, (Li0.84Fe0.16)OHFeSe, CaKFe4As4, and LiFeAs. In this topical review, we present an overview of the recent STM studies on the MZMs in IBSs. We start with the observation of MZMs in the vortices in FeTe0.55Se0.45 and discuss the pros and cons of FeTe0.55Se0.45 compared with other platforms. We then review the following up discovery of MZMs in vortices of CaKFe4As4, impurity-assisted vortices of LiFeAs, and quantum anomalous vortices in FeTe0.55Se0.45, illustrating the pathway of the developments of MZM research in IBSs. Finally, we give perspective on future experimental works in this field. 相似文献