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Extreme central L-values of almost prime quadratic twists of elliptic curves

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Science China Mathematics 2023年第12期66卷 2755-2766页

作者： Shenghao hua Bingrong huang Data Science Institute and School of Mathematics Shandong UniversityJinan 250100China

In this paper,we prove the extreme values of L-functions at the central point for almost prime quadratic twists of an elliptic *** an application,we get the extreme values for the Tate-Shafarevich groups in the quadra... 详细信息

关键词： extreme value quadratic twist central L-value elliptic curve almost prime

Role of bonding filling on HER/OER/ORR multifunctional catalytic activity in transition-metals-doped PdPX(X=S,Se,Te)

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Rare Metals 2024年第10期43卷 5126-5140页

作者： Hai-hua huang Wei Li Cheng-Chao Hu Xue-Qin Sun Lin-guo Lu Xiao-Feng Fan School of Materials Science and Engineering Laboratory of Sensitive Materials and DevicesShandong Department of EducationLiaocheng UniversityLiaocheng 252059China School of Environmental and Material Engineering Yantai UniversityYantai 264005China Department of Physics University of Puerto RicoRio PiedrasSan Juan.PR00931USA Key Laboratory of Automobile Materials(Jilin University) Ministry of EducationCollege of Materials Science and EngineeringJilin UniversityChangchun 130012China

The development of stable and highly efficien multifunctional electrocatalysts for the hydrogen evolution reaction(HER),oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)are essential for the efficient conversion and storage of renewable *** significant advantages of single-atom catalysts,such as strong metal slab interactions,unsaturated coordination and efficient atomic utilization,have opened new avenues for designing multifunctional ***,based on density functional theory,a single atom doped PdPX system was designed as a multifunctional electrocatalyst,which demonstrated the synergistic effect between defects and transition metal atoms and led to enhanced catalytic *** results showed that PdPS/PdPSe with P/X vacancy,PdPTe with P/Pd vacancy and Co/Rh/Ir@PdPX exhibited promising HER ***@PdPS(Se),with an overpotential of 0.56(0.44)V,was predicted to be a promising OER ***,Rh(Ir)@PdPS(Se)catalysts exhibited efficient catalytic properties for ORR Besides,Co@PdPS(Se),Rh(Ir)@PdPS~(V(S)),Co@PdP-Se~(V(Se))and Ir@PdPS~(V(S)-1)exihibited multifunctional catalytic performance with moderate ***,the origin of catalytic activity was revealed by using the crystal orbital Hamilton populations *** a strong adsorption system,proper filling of the anti-bonding state can increase the energy of the system,weaken the adsorption strength,and facilitate the desorption of intermediates Conversely,augmenting bonding states can enhance its adsorption *** findings provide theoretica guidance for the design and fabrication of novel multifunctional electrocatalysts in terms of filling of bondingstate.

关键词： Electrocatalyst Two-dimensional PdPX Water splitting Density functional theory

Frequency Measurement of the Electric Quadrupole Transition in a Single Laser-Cooled 40Ca＋

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Chinese Physics Letters 2011年第1期28卷 74-77页

作者： LIU Qu huang Yao CAO Jian OU Bao-Quan guo Bin GUAN hua huang Xue-Ren GAO Ke-Lin State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics (WIPM) Chinese Academy of Sciences Wuhan 430071 Centers for Cold Atom Physics Chinese Academy of Sciences Wuhan 430071 Graduate School of the Chinese Academy of Sciences Beijing 100049 Department of Physics Science College National University of Defense Technology Changsha 410073

The optical frequency of the 4s2S1/2 3d2 Ds/2 transition in a single trapped and laser-cooled 40 Ca＋ ion is measured with an optical frequency comb system referenced to a hydrogen maser, A 729-nm laser can be locked ... 详细信息

关键词： Lasers Measurement

Microstructure and High-Temperature Oxidation Behavior of Dy-Doped Nb–Si-Based Alloys

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Acta Metallurgica Sinica(English Letters) 2018年第7期31卷 742-752页

作者： Yue-Ling guo Li-Na Jia hua-Rui Zhang Bin Kong Yong-Lin huang Hu Zhang School of Materials Science and Engineering Beihang University

Microstructures and oxidation behaviors of four Dy-doped Nb-Si-based alloys at 1250 ℃ were investigated. The nominal compositions of the four alloys are Nb-15Si-24Ti-4Cr-2Al-2Hf-xDy （at.%）, where x = 0, 0.05, 0.10 and 0.15, respectively. Results showed that the four alloys all consisted of Nbss, αNbsSi3 and γNbsSi3, and the addition of Dy produced no obvious effect on the phase constitution and the microstructures of Nb-Si-based alloys. After oxidation at 1250 ℃ for 58 h, it was found that the addition of Dy accelerated the oxidation rate of Nb-Si-based alloys and caused a larger weight gain, accompanied by the formation of a more porous and less protective oxide scale. The oxides of Nb2O5, Ti2Nb10O29, TiNb2O7, Ti0.4Cr0.3Nb0.302 and glassy SiO2 were formed on Dy-doped Nb-Si-based alloys. The high- temperature oxidation mechanism of Dy-doped Nb-Si-based alloys was discussed.

关键词： Nb-Si alloy Intermetallics Directional solidification - Oxidation - Microstructure

Buried interface bridging for inverted cesium-formamidinium triiodide perovskite solar cells with long operational stability

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Science China Chemistry 2025年第1期 163-173页

作者： Chenhui Zhang Chunjun Liang Fulin Sun Ting Zhu Xinghai huang Yuzhu guo Xinyu guo Kunyang Ge Dan Li Fangtian You Zhiqun He Key Laboratory of Luminescence and Optical Information Ministry of Education Institute of Optoelectronic TechnologyBeijing Jiaotong University Department of Physics School of Physical Science and Engineering Beijing Jiaotong University

In the field of perovskite solar cells(PSCs), the research on defects in the buried interface has been relatively limited due to its non-exposure; however, this interface significantly impacts the performance enhancement of inverted PSCs. This study employs phenylethylammonium chloride(PEACl) molecules as a buffer layer to modify the buried interface of p-i-n structured PSCs,aiming to enhance the uniformity of self-assembled monolayers(SAMs) and facilitate the uniform nucleation and growth of perovskite films on the substrate. Furthermore, the introduction of the PEACl buffer layer effectively passivates defects at the bottom of the perovskite layer and notably enhances the crystal quality of the perovskite film by mitigating residual stress,thereby reducing nonradiative recombination loss. Following these optimizations, the MA-free PSCs treated with PEACl achieve a power conversion efficiency(PCE) of 24.11%, with significant improvements in storage, thermal stability, and operational stability. Particularly noteworthy is the device's performance in an unencapsulated state, whereas after 1,500 hours of continuous light operation stability testing, it retains 97% of its original efficiency. This study not only enriches the systematic understanding of the characteristics of the buried interface in PSCs but also contributes significantly to advancing the commercial production of perovskite photovoltaic technology.

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Tensor Couplings of ω- and ρ-Mesons with Nucleons in a Derivative Scalar Coupling Model for Finite Nuclei

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Chinese Physics Letters 2001年第7期18卷 891-893页

作者： guo hua HU Xiang Department of Technical Physics and MOE Laboratory of Heavy Ion Physics Peking UniversityBeijing 100871

Theω-andρ-meson tensor couplings to nucleons in a derivative scalar coupling model for finite nuclei are *** influences of the tensor couplings on the binding energies per nucleon,the root-mean-square charge radii,spin-orbit splittings and single particle energies are *** obtained results show that the spin-orbit splittings for finite nuclei are more sensitive to theω-meson tensor coupling.

关键词： tensor coupling meson

Eigen elastic mechanics and its variation principle

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中国有色金属学会会刊：英文版 2001年第2期11卷 281-282页

作者： guo Shao-hua 郭少华 College of Resources Environment and Civil Engineering Central South University

The fundamental equations and the corresponding boundary condition of elastic mechanics under mechanical representation are given by using the conception of eigen space and elastic variation principle. It is proved theoretically that the solution of anisotropic elastic mechanics consists of modal ones, which are obtained respectively from the modal equation of the different subspaces. A simple application is also given.

关键词： anisotropy eigen elastic mechanics variation principle modal equation

The Henan extreme rainfall in July 2021: Modulation of the northward-shift monsoon trough on the synoptic-scale wave train

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Advances in Climate Change Research 2022年第6期13卷 819-825页

作者： Si-hua huang Zhi-Ping WEN Xiao-Dan CHEN Yuan-Yuan guo Zhe-Wen WANG Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China Institute of Eco-Chongming(IEC) Shanghai 200062China Innovation Center of Ocean and Atmosphere System Zhuhai Fudan Innovation Research InstituteZhuhai 518057China Jiangsu Collaborative Innovation Center for Climate Change Nanjing 210023China Zhumadian Meteorological Office Zhumadian 463000China

The synoptic-scale wave train is a dominant pattern of the synoptic variability over the tropical western Pacific and usually affects the extreme weather over South China and Southeast *** it could extend its influence and contribute to the Henan extreme rainfall in July 2021 still needs to be *** found that during the Henan extreme rainfall days a positively synoptic-scale vorticity disturbance dominated Henan province,China,which was embedded in the synoptic-scale wave train that originated from the western North ***,the propagating pathway of this synoptic-scale wave train located northward and was likely modulated by the latitudinal location change of the monsoon trough over the western North Pacific.A northernmost displacement of the monsoon trough in July 2021(∼23.2°N)would facilitate the synoptic-scale wave train to propagate farther northwestward via shifting the related barotropic conversion ***,the synoptic-scale wave train from the tropics could reach Henan,provide the necessary lifting forcing,and supply abundant water vapor associated with the anomalous southerly for the occurrence of Henan extreme rainfall *** results implicate that the pre-existing synoptic-scale wave train regulated by the location of the monsoon trough may be a potential precursor for heavy rainfalls in northern Central China.

关键词： Extreme rainfall Northern Central China Synoptic-scale wave train Monsoon trough Barotropic energy conversion

Periodic Folded Wave Patterns for(2+1)-Dimensional Higher-Order Broer-Kaup Equation

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Communications in Theoretical Physics 2008年第10期50卷 827-831页

作者： huang Wen-hua College of Science Huzhou University Huzhou 313000 China Shanghai Institute of Mathematics and Mechanics Shanghai University Shanghai 200072 China

A general solution including three arbitrary functions is obtained for the (2+1)-dimensional higher-orderBroer-Kaup equation by means of WTC truncation *** proper multiple valued functions and Jacobielliptic functions in the seed solution,special types of periodic folded waves are *** long wave limit theseperiodic folded wave patterns may degenerate into single localized folded solitary wave *** interactions ofthe periodic folded waves and their degenerated single folded solitary waves are investigated graphically and are foundto be completely elastic.

关键词： higher-order Broer Kaup equation WTC truncation method periodic folded wave