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“Zero‑Strain” NiNb_(2)O_(6) Fibers for All‑Climate Lithium Storage

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Nano-Micro Letters 2025年第1期17卷 348-360页

作者： Yan Zhao Qiang Yuan Liting Yang Guisheng Liang Yifeng Cheng Limin Wu Chunfu Lin Renchao Che College of physics Donghua UniversityShanghai 201620People’s Republic of China school of Materials Science and Engineering Institute of Materials for Energy and EnvironmentQingdao UniversityQingdao 266071People’s Republic of China Laboratory of Advanced Materials Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsAcademy for Engineering&TechnologyFudan UniversityShanghai 200438People’s Republic of China Zhejiang Laboratory Hangzhou 311100People’s Republic of China Inner Mongolia University Hohhot 010021People’s Republic of China

Niobates are promising all-climate Li^(+)-storage anode material due to their fast charge transport,large specific capacities,and resistance to electrolyte ***,their moderate unit-cellvolume expansion(generally 5%–10%)during Li^(+)storage causes unsatisfactory long-term ***,“zero-strain”NiNb_(2)O_(6) fibers are explored as a new anode material with comprehensively good electrochemical *** Li^(+)storage,the expansion of electrochemical inactive NiO_(6) octahedra almost fully offsets the shrinkage of active NbO_(6) octahedra through reversible O *** superior volume-accommodation capability of the NiO_(6) layers guarantees the“zero-strain”behavior of NiNb_(2)O_(6) in a broad temperature range(0.53%//0.51%//0.74%at 25//−10//60℃),leading to the excellent cyclability of the NiNb_(2)O_(6) fibers(92.8%//99.2%//91.1%capacity retention after 1000//2000//1000 cycles at 10C and 25//−10//60℃).This NiNb_(2)O_(6) material further exhibits a large reversible capacity(300//184//318 mAh g−1 at 0.1C and 25//−10//60℃)and outstanding rate performance(10 to 0.5C capacity percentage of 64.3%//50.0%//65.4%at 25//−10//60℃).Therefore,the NiNb_(2)O_(6) fibers are especially suitable for large-capacity,fast-charging,long-life,and all-climate lithium-ion batteries.

关键词： NiNb_(2)O_(6)porous fiber “Zero-strain”mechanism Electrochemical property Harsh-temperature operation Operando characterization

Manipulation of multiple electromagnetically induced two-photon transparency in a six-level atomic system

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Chinese physics B 2009年第6期18卷 2282-2287页

作者：贾文志王顺金 Center of Theoretical physics School of PhysicsSichuan University

In the five-level K-type atomic system, by using another control field to couple the excited level of the coupling transition to the sixth higher excited level, a six-level atomic system is constructed. In this system, the multiple electromagnetically induced two-photon transparency has been investigated. What is more, if choosing the parameters of the control fields properly the triple transparency window will reduce to a double one which means that the multiple electromagnetically induced two-photon transparency can be manipulated in this system. The physical interpretation of these phenomena is given in terms of the dressed states and the dark states.

关键词： electromagnetically induced transparency dressed states dark states

a-C∶F∶H films prepared by PECVD

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中国有色金属学会会刊：英文版 2004年第3期14卷 426-429页

作者：刘雄飞肖剑荣简献忠王金斌高金定 school of physics Science and Technology school of Electric Engineering Institute of Technology physics

Fluorinated amorphous hydrogenated a-C∶F∶H carbon thin films were deposited using radio frequency plasma enhanced chemical vapor deposition（RF-PECVD） reactor with CF4 and CH4 as source gases and were annealed in a N2 atmosphere. The properties of these films were evaluated by FTIR spectrometry, UV-VIS spectrophotometry and single-wavelength spectroscopic ellipsometry. A correspondence relativity connection between the deposition rate and technology was found. The chemical bonding structures and the content of CHx and CFx in the films are transformed and the optical band gap decreases monotonically with increasing temperature after annealing. The dielectric constant is increased with decreasing content of F in the films and the optical band gap is decreased with decreasing the content of H in the film.

关键词： a-C:F:H薄膜 PECVD 制备电介质常数 ULSI 光学薄膜

Photoelectron longitudinal momentum distributions containing nondipole effects

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Chinese physics B 2018年第1期27卷 335-340页

作者：霍一宁李健马凤才 school of physics Liaoning University Department of physics Shenyang Aerospace University school of physics Science and Technology Inner Mongolia University

This paper proposes a modified strong field approximation model for evaluating nondipole effects on the ionization of an atom in an intense laser field. The photoelectron longitudinal momentum distributions （PLMD） of a hydrogen-like atom exposed to a mid-infrared laser field is calculated. The theoretical results indicate an obvious asymmetry in the PLMD, and an offset of the PLMD peak appears in the opposite direction of the beam propagation due to nondipole effects. The peak offsets of the PLMD increased with the laser intensity, imposed by the initial state of the hydrogen-like atom.

关键词： strong field approximation photoelectron longitudinal momentum distributions nondipole effects

Influence of Mn-Doped Content on Ferromagnetism of Ga1-xMnxN Film Grown by LP-MOVPE

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Chinese physics Letters 2006年第6期23卷 1585-1587页

作者：张斌姚淑德王坤丁志博陈志涛苏月永张国义马宏骥聂锐张亚伟 Department of Technical physics School of Physics Peking University Beijing 100871 Department of physics School of Physics Peking University Beijing 100871

The diluted magnetic semiconductor Ga1-xMnxN was achieved by low-pressure metal organic vapour-phase epitaxy （LP-MOVPE）. Proton-induced x-ray emission was employed non-destructively, quickly and accurately to determine the Mn-doped content. The magnetic property was measured by a superconducting-quantuminterference-device （SQID） magnetometer. Apparent ferromagnetic hysteresis loops measured at or above room temperature are presented. No ferromagnetic secondary phases were detected by high-resolution x-ray diffraction. The experimental results show that the ferromagnetic signal firstly decreases and then increases with the increasing Mn-doped content from 0.23% to 4.69% and it is the weakest when Mn content is 0.51%. The annealing treatment could make the ferromagnetic property stronger.

关键词： PIXE SEMICONDUCTORS (GA MN)AS CHINA

Atmospheric Pressure Plasma Jet in Ar and O_2/Ar Mixtures:Properties and High Performance for Surface Cleaning

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Plasma Science and Technology 2013年第12期15卷 1203-1208页

作者：金英任春生杨亮张家良王德真 school of Mathematic and physics Bohai University school of physics and Optoelectronic Technology Dalian University of Technology

An atmospheric pressure plasma jet generated in Ar and O2/Ar mixtures has been investigated by specially designed equipment with double power electrodes at 20~32 kHz, and their effects on the cleaning of surfaces have been studied. Properties of the jet discharge are studied by electrical diagnostics, including the waveform of discharge voltage, discharge current and the Q-V Lissajous figures. The optical emission spectroscopy is used to measure the plasma parameters, such as the excitation temperature and the gas temperature. It is found that the consumed power and the excitation temperature increase with increase of the discharge frequency. On the other hand, at the same discharge frequency, these parameters in O2/Ar mixture plasma are found to be much larger. The effect on surface cleaning is studied from the changes in the contact angle. For Ar plasma jet, the contact angle decreases with increase of the discharge frequency. For O2/Ar mixture plasma jet, the contact angle decreases with increase of discharge frequency up to 26 kHz, however, further increase of discharge frequency does not show further decrease in the contact angle. At the same discharge frequency, the contact angle after O2/Ar mixture plasma cleaning is found to be much lower compared to the case of pure Ar. From the results of quadrupole mass-spectrum analysis, we can identify more fragment molecules of CO and H2O in the emitted gases after O2/Ar plasma jet treatment compared with Ar plasma jet treatment, which are produced by the decomposition of surface organic contaminants during the cleaning process.

关键词： atmospheric pressure plasma jet surface cleaning the excitation temperature,the contact angle quadrupole mass-spectrum

Laser-induced fabrication of highly branched CuS nanocrystals with excellent near-infrared absorption properties

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Chinese physics B 2017年第7期26卷 270-275页

作者：杨汝雨张中义徐林林李爽焦扬张华陈明 school of physics Shandong University school of Science Shandong Jianzhu University school of physics and Electronics Shandong Normal University

We report on the successful fabrication of highly branched Cu S nanocrystals by laser-induced photochemical ***, the single-crystalline nature with preferential alignment of the（107） orientation can be well improved during the moderate growth process. The branch length drastically increases from about 5 nm to 6 μm with an increase of photochemical reaction time（0-40 min）. The absorption spectra of as-prepared Cu S nanodendrites show that localized surface plasmon resonance（LSPR） peaks can be modulated from about 1037 nm to 1700 nm with an increase of branch length. Our results have a promising potential for photodynamic therapy and biological imaging application.

关键词： laser-induced photochemical reaction Cu S nanodendrites single-crystalline nature near-infrared absorption

An efficient quantum proactive incremental learning algorithm

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Science China(physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 49-57页

作者： Lingxiao Li Jing Li Yanqi Song Sujuan Qin Qiaoyan Wen Fei Gao State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications school of Cyberspace Security Beijing University of Posts and Telecommunications

In scenarios where a large amount of data needs to be learned, incremental learning can make full use of old knowledge, significantly reduce the computational cost of the overall learning process, and maintain high performance. In this paper, taking the MaxCut problem as our example, we introduce the idea of incremental learning into quantum computing, and propose a Quantum Proactive Incremental Learning algorithm(QPIL). Instead of a one-off training of quantum circuit, QPIL contains a multi-phase training on gradually-increased subgraphs of all vertices, proactively reducing large-scale problems to smaller ones to solve in steps, providing an efficient solution for MaxCut. Specifically, some vertices and corresponding edges are randomly selected for training to obtain optimized parameters of the quantum circuit at first. Then, in each incremental phase, the remaining vertices and corresponding edges are gradually added and the parameters obtained from the previous phase are reused in the parameter initialization of the current phase. We perform experiments on 120 different small-scale graphs, and it shows that QPIL performs superior to prevalent quantum and classical baselines in terms of approximation ratio(AR), time cost, anti-forgetting, and solving stability. In particular, QPIL's AR surpasses 20% of mainstream quantum baselines, and the time cost is less than 1/5 of them. The idea of QPIL is expected to inspire efficient and high-quality solutions in large-scale Max Cut and other combinatorial optimization problems.

关键词： variational quantum algorithm incremental learning multi-phase training MaxCut quantum computing

The influence of electric field on the photodetachment of H^- near a metal surface

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Chinese physics B 2010年第6期19卷 265-271页

作者：黄凯云王德华 school of physics Ludong University

The influence of electric field on the photodetachment of H- near a metal surface is investigated based on the closed-orbit theory. It is found that the photodetachment of H- near a metal surface is not only related to the electric field strength but also to the electric field direction. If the electric field is along the ＋z axis, it can strengthen the oscillation in the photodetachment cross section. However, if the electric field is along the -z axis, since the direction of electric field force is opposite to that of static-image force caused by the metal surface, the situation becomes much more complicated. When the electric field is very weak, its influence can be neglected. The photodetachment cross section is nearly the same as that when a single metal surface exists. When the electric field strength is strong enough, the electric field force is able to counteract the metallic attraction, therefore no closed orbit is formed. If the electric field continues to increase until its influence becomes dominant, the photodetachment cross section approaches the case of the photodetachment of H^- in an electric field. Our results may be useful for guiding future experimental studies on the photodetachment of negative ions near surfaces.

关键词： closed-orbit theory photodetachment electric field metal surface