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排序方式: 共有217条查询结果,搜索用时 46 毫秒
211.
《汉语大词典》是当前最权威的语文工具书,但一些比较常用的词语却没有收录,例如:霍地、霍然、却好、并然、干自、不时间、平地里等,这些词语的使用频率还不低。《汉语大词典》之所以漏收,主要是对附加式词语的重视不够,补充几条,对以后《汉语大词典》的重修应有一定的参考作用。 相似文献
212.
采用文献资料法、社会调查法和数理统计等研究方法,对咸宁市社区体育进行了调查和研究,发现咸宁市社区体育存在参与人数少、消费观念落后、缺乏指导员和相应组织机构、公共设施利用率低等问题,并针对问题提出相应完善措施。为咸宁市社区体育发展提供参考意见。 相似文献
213.
Agata Michalska 《Electroanalysis》2012,24(6):1253-1265
This paper is aiming to give a brief overview of recent research in the field of all‐solid‐state, internal solution free, ion‐selective electrodes and reference electrodes, employing conducting polymers or nano‐/microstructures as solid contacts beneath the polymeric, ion‐selective or reference membranes. The emphasis is on papers published in the last five years (after 2006). According to the papers published, poly(3‐octylthiophene) conducting polymer transducers offer highly reliable sensors for various applications, involving demanding analytical approaches and miniature sensors. On the other hand, the search for alternative materials continues: the sensors obtained by placing nano‐/microstructures (conducting polymers but also other materials, like, e.g., carbon nanotubes) underneath the receptor membrane are intensively tested. The recent years have also shown how useful the application of advanced instrumental methods is for the investigation of processes occurring within all‐solid‐state ion‐selective electrodes. 相似文献
214.
The Exact Limits and Improved Decay Estimates for All Order Derivatives of the Global Weak Solutions to a Two-Dimensional Incompressible Dissipative Quasi-Geostrophic Equation
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Linghai Zhang 《Journal of Nonlinear Modeling and Analysis》2023,5(1):146-202
We will accomplish the exact limits for all order derivatives of the global weak solutions to a two-dimensional incompressible dissipative quasi-geostrophic equation. We will also establish the improved decay estimates with sharp rates for all order derivatives. We will consider two cases for the initial function and the external force and prove the optimal results for both cases. We will couple together existing ideas (including the Fourier transformation and its properties, Parseval''s identity, iteration technique, Lebesgue''s dominated convergence theorem, Gagliardo-Nirenberg-Sobolev interpolation inequality, squeeze theorem, Cauchy-Schwartz''s inequality, etc) existing results (the existence of global weak solutions, the existence of local smooth solution on $(T,\infty)$ and the elementary decay estimate with a sharp rate) and a few novel ideas to obtain the main results. 相似文献
215.
Dr. Laidong Zhou Dr. J. David Bazak Dr. Baltej Singh Chang Li Dr. Abdeljalil Assoud Dr. Nancy M. Washton Dr. Vijayakumar Murugesan Prof. Linda F. Nazar 《Angewandte Chemie (International ed. in English)》2023,62(30):e202300404
We report a new sodium fast-ion conductor, Na3B5S9, that exhibits a high Na ion total conductivity of 0.80 mS cm−1 (sintered pellet; cold-pressed pellet=0.21 mS cm−1). The structure consists of corner-sharing B10S20 supertetrahedral clusters, which create a framework that supports 3D Na ion diffusion channels. The Na ions are well-distributed in the channels and form a disordered sublattice spanning five Na crystallographic sites. The combination of structural elucidation via single crystal X-ray diffraction and powder synchrotron X-ray diffraction at variable temperatures, solid-state nuclear magnetic resonance spectra and ab initio molecular dynamics simulations reveal high Na-ion mobility (predicted conductivity: 0.96 mS cm−1) and the nature of the 3D diffusion pathways. Notably, the Na ion sublattice orders at low temperatures, resulting in isolated Na polyhedra and thus much lower ionic conductivity. This highlights the importance of a disordered Na ion sublattice—and existence of well-connected Na ion migration pathways formed via face-sharing polyhedra—in dictating Na ion diffusion. 相似文献
216.
A.M.C. Dawes D.J. Gauthier S. Schumacher N.H. Kwong R. Binder A.L. Smirl 《Laser \u0026amp; Photonics Reviews》2010,4(2):221-243
We review recent theoretical and experimental efforts toward developing an all‐optical switch based on transverse optical patterns. Transverse optical patterns are formed when counterpropagating laser beams interact with a nonlinear medium. A perturbation, in the form of a weak switch beam injected into the nonlinear medium, controls the orientation of the generated patterns. Each state of the pattern orientation is associated with a state of the switch. That is, information is stored in the orientation state. A realization of this switch using a warm rubidium vapor shows that it can be actuated by as few as 600 ± 40 photons with a response time of 5 µs. Models of nonlinear optical interactions in semiconductor quantum wells and microresonators suggest these systems are also suitable for use as fast all‐optical switches using this same conceptual design, albeit at higher switching powers. 相似文献
217.
Taewon Kim Sang Hyeok Ahn You-Yeob Song Beom Jin Park Chanhee Lee Ahreum Choi Dr. Min-Ho Kim Prof. Dong-Hwa Seo Prof. Sung-Kyun Jung Prof. Hyun-Wook Lee 《Angewandte Chemie (International ed. in English)》2023,62(42):e202309852
Conventional solid electrolyte frameworks typically consist of anions such as sulphur, oxygen, chlorine, and others, leading to inherent limitations in their properties. Despite the emergence of sulphide, oxide, and halide-based solid electrolytes for all-solid-state batteries, their utilization is hampered by issues, including the evolution of H2S gas, the need for expensive elements, and poor contact. Here, we first introduce Prussian Blue analogue (PBA) open-framework structures as a solid electrolyte that demonstrates appreciable Na+ conductivity (>10−2mS cm−1). We delve into the relationship between Na+ conductivity and the lattice parameter of N-coordinated transition metal, which is attributed to the reduced interaction between Na+ and the framework, corroborated by the distribution of relaxation times and density functional theory calculations. Among the five PBAs studied, Mn-PBA have exhibited the highest Na+ conductivity of 9.1×10−2mS cm−1. Feasibility tests have revealed that Mn-PBA have maintained a cycle retention of 95.1 % after 80cycles at 30 °C and a C-rate of 0.2C. Our investigation into the underlying mechanisms that play a significant role in governing the conductivity and kinetics of these materials contributes valuable insights for the development of alternative strategies to realize all-solid-state batteries. 相似文献