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福建省少年儿童体操发展现状分析

福建体育科技 2001年第1期20卷 21-25页

作者：林子铮张涵劲江芸方熙嫦陈显松福建师范大学体育系福建福州350007

采用文献资料法与数理统计法 ,对福建省少年儿童体操运动的发展现状进行了研究。结果表明 :我省从事少年儿童体操训练的人数明显增多 ,各组别成绩有不同程度的提高 ,尤其是男子甲、乙组 ,女子乙、丁组运动员获高分人数增多了。但各组别... 详细信息

采用文献资料法与数理统计法 ,对福建省少年儿童体操运动的发展现状进行了研究。结果表明 :我省从事少年儿童体操训练的人数明显增多 ,各组别成绩有不同程度的提高 ,尤其是男子甲、乙组 ,女子乙、丁组运动员获高分人数增多了。但各组别运动员都有明显的弱项 ,整体实力不强。建议完善我省业余训练与竞赛改革 ,加强运动员的基本姿态与基本技术的系统训练。

关键词：福建省少年儿童体操发展现状

Novel regulation of the eEF2K/eEF2 pathway:prospects of'PQBP1 promotes translational elongation and regulates hippocampal mGluR-LTD by suppressing eEF2 phosphorylation'

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Journal of Molecular Cell Biology 2021年第5期13卷 392-394页

作者： Yuqian Shen Junhai han zi Chao zhang School of Life Science and Technology Key Laboratory of Developmental Genes and Human DiseaseSoutheast UniversityNanjing 210096China Co-innovation Center of Neuroregeneration Nantong UniversityNantong 226001China

Protein synthesis involves initiation,elongation,and termination.A number of studies show that translation elongation is highly regulated and is the most energy-intensive process,which controls the efficiency and accuracy of protein *** the elongation process,eukaryotic elongation factor 2(eEF2)binds to the ribosome to induce its conformation change and promotes the translocation of the tRNAs by hydrolyzing guanosine triphosphate,which then allows the next AA-tRNA to enter the A site for translation *** activity of eEF2 is negatively regulated by its kinase eEF2K that phosphorylates eEF2 at threonine-56(Thr56).

关键词： synthesis EF2 translational

Power-law Distribution and Scale-invariant Structure from the First CHIME/FRB Fast Radio Burst Catalog

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Research in Astronomy and Astrophysics 2023年第2期23卷 42-46页

作者： zi-han Wang Yu Sang Xue zhang Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009.China Shanghai Frontier Science Research Center for Gravitational Wave Detection School of Aeronautics and AstronauticsShanghai Jiao Tong UniversityShanghai 200240China

We study the statistical property of fast radio bursts(FRBs) based on a selected sample of 190 one-off FRBs in the first CHIME/FRB *** power law models are used in the analysis,and we find the cumulative distribution functions of energy can be well fitted by bent power law and thresholded power law *** distribution functions of fluctuations of energy well follow the Tsallis q-Gaussian *** q values in the Tsallis q-Gaussian distribution are constant with small fluctuations for different temporal scale intervals,indicating a scale-invariant structure of the *** earthquakes and soft gamma repeaters show similar properties,which are consistent with the predictions of self-organized criticality systems.

关键词： methods statistical-radio continuum galaxies-catalogs

Minimum safe thickness of rock plug in karst tunnel according to upper bound theorem

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Journal of Central South University 2016年第9期23卷 2346-2353页

作者： YANG zi-han zhang Jia-hua School of Civil Engineering Central South University Changsha 410075 China

High pressure and water-bearing caverns ahead of a karst tunnel face tend to cause geological disasters, such as water and mud bursts. So, the determination of safe thickness of the reserved rock plug is a key technical problem to be solved for karst tunnel construction. Based on the Hoek-Brown nonlinear failure criterion, the minimum safe thickness of rock plug was investigated in the light of the limit analysis theory. On the basis of the proposed failure mode, the expression of the minimum thickness for rock plug was obtained by means of upper bound theorem in combination with variational principle. The calculation results show the influence of each parameter on safe thickness and reveal the damage range of rock plug. The proposed method is verified by comparing the results with those of the drain cavern of Maluqing Tunnel. The research shows that with the increase of compressive strength and tensile strength as well as constant A of Hoek-Brown criterion, the safe thickness decreases, whereas with the increase of cavern pressure, tunnel diameter, and constant B from Hoek-Brown criterion, the safe thickness increases. Besides, the tensile strength, or constants A and B affect the shear failure angle of rock plug structure, but other parameters do not. In conclusion, the proposed method can predict the minimum safe thickness of rock plug, and is useful for water burst study and prevention measures of tunnels constructed in high-risk karst regions.

关键词： karst tunnels rock plug minimum safe thickness upper limit theorem failure mode

Spatial-temporal Evolution Characteristics and Decoupling Analysis of Influencing Factors of China’s Aviation Carbon Emissions

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Chinese Geographical Science 2022年第2期32卷 218-236页

作者： han Ruiling LI Lingling zhang Xiaoyan LU zi ZHU Shaohua Post-doctoral Mobile Station for Scientific Research of Geography Hebei Normal UniversityShijiazhuang 050024China College of Home Economics Hebei Normal UniversityShijiazhuang 050024China College of Geographical Sciences Hebei Normal UniversityShijiazhuang 050024China

The aviation industry has become one of the top ten greenhouse gas emission industries in the world. China’s aviation carbon emissions continue to increase, but the analysis of its influencing factors at the provincial level is still incomplete. This paper firstly uses Stochastic Impacts by Regression on Population, Affluence and Technology model(STIRPAT) model to analyze the time series evolution of China’s aviation carbon emissions from 2000 to 2019. Secondly, it uses the Logarithmic Mean Divisia Index(LDMI) model to analyze the influencing characteristics and degree of four factors on China’s aviation carbon emissions, which are air transportation revenue, aviation route structure, air transportation intensity and aviation energy intensity. Thirdly, it determines the various factors’ influencing direction and evolution trend of 31 provinces’ aviation carbon emissions in China(not including Hong Kong, Macao, Taiwan of China due to incomplete data). Finally, it derives the decoupling effort model and analyzes the decoupling relationship and decoupling effort degree between air carbon emissions and air transportation revenue in different provinces. The study found that from 2000 to2019, China’s total aviation carbon emissions continued to grow, while the growth rate of aviation carbon emissions showed a fluctuating downward trend. Air transportation revenue and aviation route structure promote the growth of total aviation carbon emissions, and air transportation intensity and aviation energy intensity have a restraining effect on the growth of total aviation carbon emissions. The scope of negative driving effect of air transportation revenue and air transportation intensity on total aviation carbon emissions in various provinces has increased. While the scope of positive driving influence of aviation route structure on total aviation carbon emissions of various provinces has increased, aviation energy intensity mainly has negative driving influence on total aviation

关键词： aviation carbon emissions influencing factors spatial and temporal analysis decoupling China

Dependence of Morphology of SiO_(x) Nanowires on the Supersaturation of Au-Si Alloy Liquid Droplets Formed on the Au-Coated Si Substrate

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Chinese Physics Letters 2001年第11期18卷 1529-1532,I0001,I0002页

作者： zhang han LI Ji-Xue JIN Ai-zi zhang Ze Beijing Laboratory of Electron Microscopy Institute of PhysicsChinese Academy of SciencesP.O.Box 2724Beijing 100080 Department of Material Science and Engineering Tsinghua UniversityBeijing 100084 Department of Material Science Jilin Institute of TechnologyChangchun 130025 Laboratory of Super-hard Material Jilin UniversityChangchun 130023

A thermodynamic theory about the dependence of morphology of SiOx nanowires on the super-saturation of alloy liquid droplets has been proposed on the basis of the vapour-liquid-solid growth mechanism and has been supported experimentally. By changing the Si concentration in the Au-Si liquid droplets formed on the Au-coated Si substrate, firework-, tulip- and bud-shaped SiOx nanowires were synthesized by a thermal evaporation method and distributed concentrically around some void defects in the Si substrate. Voids were formed underneath the surface of the Si substrate during the thermal evaporation at 850℃ and resulted in the Si-concentration deficient thus different saturation of Au-Si droplets. Electron microscopy analysis showed that the nanowires had an amorphous structure and were terminated by Au-Si particles.

关键词： alloy saturation vapour

The Generalized Joint Density of States and Its Application to Exploring the Pairing Symmetry of High-Tc Superconductors

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Chinese Physics Letters 2013年第5期30卷 144-147页

作者： zhang Dan-Bo han Qiang WANG zi-Dan Department of Physics Renmin University of ChinaBeijing 100872 Department of Physics and Center of Theoretical and Computational Physics The University of Hong KongPokfulam RoadHong Kong

We introduce a generalized joint density of states(GJDOS),which incorporates the coherent factors into the JDOS,to study quasiparticle interference(QPI)in *** intimate relation between the Fourier-transformed local density of states and GJDOS is revealed:they correspond respectively to the real and imaginary parts of a generalized impurity-response function,and particularly share the same angular factors and singular boundaries,as seen from our approximate analytic results for d-wave ***,our numerical GJDOS analysis agrees well with the QPI patten of d-wave cuprates and s_(±)-wave iron-based ***,we illustrate that the present GJDOS scenario can uncover the sign features of the superconducting gap and thus can be used to explore the pairing symmetry of the A_(1-x)Fe_(2-y)Se_(2)(A=K,Cs,etc)superconductors.

关键词： imaginary symmetry transformed

Three-dimensional numerical simulation and earth pressure analysis on double-row piles with consideration of spatial effects

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第10期12卷 758-770页

作者： zi-han WANG Jian ZHOU Department of Geotechnical Engineering Tongji University Shanghai 200092 China

As a new kind of technology in retaining structures, the characteristics of double-row piles are significantly affected by spatial effects. In this paper, double-row piles as a retaining structure are simulated numerically in three-dimension by finite element software PLAXIS 3D FOUNDATION. The behavior differences of piles in different positions around the foundation pit are analyzed. By changing the parameters, including the length-width ratio, the excavation depth, the distance between rows and the diameter of piles, the variations of the lateral deformation, the bending moment and the earth pressure around the piles are determined. The reasonable values of parameters and some suggestions with consideration of earth pressure are proposed for the design of double-row piles as a retaining structure. The results show that the lateral deformation and bending moment are the largest in the middle of long side of the foundation pit, which is identified as the most unfavorable position. It is indicated that the earth pressure between rows above pit bottom is close to active earth pressure, while the earth pressure between rows under pit bottom is close to static earth pressure. It is suggested that 1/2-2/3 of pile length, 0.6-1.2 m, 3d-6d, and 2d-2.5d be chosen as embedded depth of piles, diameter of piles, distance between rows, and distance between piles, respectively, where d is the pile diameter.

关键词： Double-row piles Retaining structure Spatial effect Finite element Earth pressure

Hierarchical self-assembly of crown ether based metal-carbene cages into multiple stimuli-responsive cross-linked supramolecular metallogel

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Science China Chemistry 2021年第7期64卷 1177-1183页

作者： zi-En zhang Yuan-Yuan An Bo Zheng Jin-Ping Chang Ying-Feng han College of Chemistry and Materials Science Northwest UniversityXi'an 710127China School of Pharmaceutical Sciences Nanjing Tech UniversityNanjing 211816China

The hierarchical self-assembly(HSA) strategy widely utilized in biological systems has been applied in artificial systems to orchestrate small building blocks into complex functional architectures. The non-interfering interactions glue various building blocks together and produce new species with attractive properties. Herein, we functionalized NHC-based assemblies with orthogonal host–guest interaction to fabricate metal-carbene based supramolecular polymer gel. A series of unique crown etherappended cylinder-like trinuclear AuIhexacarbene assemblies [Au_(3)(L)_(2)](PF_(6))_(3)(L=D1–D4, A1–A4) were synthesized from the corresponding trisimidazolium salts H_(3)-L(PF_(6))_(3)(L=D1–D4, A1–A4) in which the N-wingtip of the imidazole moieties were substituted with three identical crown ether groups of different sizes(B15C5, B18C6, B21C7, DB24C8). The gold carbene assembly is able to complex six ammonium salts without disrupting the underlying metal-carbene cylinders. In addition, the supramolecular polymer metallogel featuring a multiple-responsiveness can be formed by using [Au_(3)(A_(4))_(2)](PF_(6))_(3) appended with DB24C8 as the core and bisammonium salt as the cross-linker. The case of introducing orthogonal interaction to NHC moiety by N-wingtip substitution demonstrates the feasibility and the power of such strategy to expand the NHC-based supramolecular system and endow them with novel properties.

关键词： N-heterocyclic carbene metallogel crown ether orthogonal interaction