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Controllable photon echo phase induced by modulated pulses and chirped beat detection

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Chinese Physics B 2019年第2期28卷 247-251页

作者： Xian-Yang zhang Shuang-Gen zhang Hua-Di zhang Xiu-Rong Ma School of Electronic Information Engineering Tianjin University of Technology Key Laboratory of Film Electronic and Communication Device Engineering Research Center of Communication Devices of Ministry of Education

In this paper, we propose a scheme for photon echo chirped detection process composed of additional modulation pulses to obtain controllable geometric phase. The geometric phases are observed and measured by a beat signal between the photon echo field and the chirped field. The chirped detection model reveals that the period of the beat signal increases as the chirped rate and delay time increase. Additionally, a two-fold relationship between the modulation phase and the echo shift phase is obtained. The numerical simulations accord with the theoretical results obtained by the finite difference time domain(FDTD) method.

关键词： geometric phase photon echo chirped beat detection Bloch sphere

The output torque estimation of MCMG for agile satellites

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Acta Mechanica Sinica 2010年第1期26卷 141-146页

作者： Jingrui zhang School of spacecraft engineering Beijing Institute of Technology 100081 Beijing China

Studied in this paper are the attitude control law design and the output torque estimation problem of micro control moment gyros （MCMGs） for the agile satellites executing rapid attitude maneuver mission. An algorithm is proposed for estimating the output torques and the gimbal angular rates of MCMGs, which can help engineers to choose reasonable size for actuators so that the cost of satellite can be decreased. According to some special maneuver missions, a numerical example of attitude control system for a small satellite with MCMGs in pyramid configuration is studied, and the simulation results validate the proposed estimation algorithm.

关键词： Agile satellite Micro control moment gyro Rapid attitude maneuver

The mitophagy receptor FUN14 domaincontaining 1 (FUNDC1): A promising biomarker and potential therapeutic target of human diseases

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Genes & Diseases 2021年第5期8卷 640-654页

作者： Weilin zhang State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijing100864PR China

Mitochondrial autophagy(mitophagy)is the selective clearance of damaged or incomplete mitochondria by autophagy,which is critical for the functional integrity of the entire mitochondrial network and cell *** dysfunction of mitophagy is closely related to many diseases,it is important to study the specific molecular mechanism and pathophysiological significance of ***14 domain-containing 1(FUNDC1)is a newly identified mitochon-drial outer membrane protein that induces receptor-mediated mitophagy by its interaction with LC3 during *** expression,phosphorylation,regulation and significance of FUNDC1 are reviewed in the context of a large number of pathophysiological *** evidence has demonstrated that levels and phosphorylation states of FUNDC1 are closely related to occur-rence,progression and prognosis of various diseases including heart diseases and cancers,indi-cating that FUNDC1 may serve as a promising biomarker and potential therapeutic target.

关键词： Autophagy Biomarker FUNDC1 Heart diseases Hypoxia Mitochondria Mitochondrial ROS Platelets

Theoretical prediction and experimental realization of transition metal doped rutiles as diluted magnetic semiconductors

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Rare Metals 2006年第5期25卷 420-426页

作者： GU Yousong LI Jianmin ZHAN Xiaoyuan zhang Xiaomei FENG Ziqi zhang Yue Department of Material Physics and Chemistry University of Science and Technology Beijing Beijing 100083 China

First principle calculations have been performed to study the electron structures and magnetic properties of transition metal doped ruilles in order to predict room temperature diluted magnetic semiconductors. Different doping configurailons have been calculated to find the preferred doping site. The ground state energies of both FM and AFM states have been calculated to study the magnetic coupling between the dopants. The calculation results show the Co doped mutile has a Curie temperature of 1438 K. Co doped mille films have been prepared on Si substrate by magnetron sputtering. X-ray diffraction results show that the deposited film is ruille. Hysteresis loop curves measured by vibration sample magnetization show that the film is ferromagnetic at root temperature.

关键词： diluted magnetic semiconductor titanium oxide fast principle calculation magnetron sputtering

Preparation of slightly crosslinked monodisperse poly(maleic anhydride-cyclohexyl vinyl ether-divinylbenzene)functional microspheres with anhydride groups via precipitation polymerization

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Particuology 2015年第2期13卷 99-106页

作者： Cen Yin Anhou Xu Li Gong Luqing zhang Bing Geng Shuxiang zhang Shandong Key Laboratory of Fluorine Chemistry and Chemical Materials School of Chemistry and Chemical Engineering University of Jinan Shandong Engineering Research Center for Fluorinated Material

Slightly crosslinked monodisperse poly（maleic anhydride-cyclohexyl vinyl ether-divinylbenzene）（MA-CHVE-DVB） microspheres were prepared via precipitation polymerization while using 2,2- azobisisobutyronitrile as an initiator in a mixture of methyl ethyl ketone and n-heptane without any stabilizer. The number-average diameter of the resultant poly（MA-CHVE-DVB） microspheres ranged from 0.478 to 1.386 μm with a polydispersity index of 1.00 to 1.02 that depended on the feed ratios of the MA/CHVE/DVB monomers. The introduction of one electron donor monomer cyclohexyl vinyl ether strongly affected the yield, size, and morphology of these slightly crosslinked microspheres. Quinoline- type chelating resins were obtained after combining the poly（MA-CHVE-DVB） with 8-hydroxyquinoline; the adsorption properties of these materials were measured through their ability to remove Cu^2＋ ions from water. The poly（MA-CHVE-DVB） microspheres with low degrees of crosslinking provided more effective functional groups and therefore better ion removal capabilities. These slightly crosslinked microspheres may have applications in water treatment as well as in sensing and drug delivery.

关键词： Precipitation polymerization Crosslinked functional microspheres Cyclohexyl vinyl ether Maleic anhydride Divinylbenzene

KOH-assisted aqueous synthesis of bimetallic metal-organic frameworks and their derived selenide composites for efficient lithium storage

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International Journal of Minerals,Metallurgy and Materials 2023年第4期30卷 601-610页

作者： Shuya zhang Yanchun Xue Yutang zhang Chengxing Zhu Xingmei Guo Fu Cao Xiangjun Zheng Qinghong Kong Junhao zhang Tongxiang Fan School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Materials Science and Engineering Shanghai Jiaotong UniversityShanghai 200240China School of the Environment and Safety Engineering Jiangsu UniversityZhenjiang 212013China Foshan(Southern China)Institute for New Materials Foshan 528200China

To solve low efficiency,environmental pollution,and toxicity for synthesizing zeolitic imidazolate frameworks(ZIFs)in organic solvents,a KOH-assisted aqueous strategy is proposed to synthesize bimetallic ZIFs polyhedrons,which are used as precursors to prepare bimetallic selenide and N-doped carbon(NC)*** them,Fe–Co–Se/NC retains the three-dimensional(3D)polyhedrons with mesoporous structure,and Fe–Co–Se nanoparticles are uniform in size and evenly *** assessed as anode material for lithium-ion batteries,Fe–Co–Se/NC achieves an excellent initial specific capacity of 1165.9 m Ah·g^(-1)at 1.0 A·g^(-1),and the reversible capacity of Fe–Co–Se/NC anode is 1247.4 m Ah·g^(-1)after 550 *** is attributed to that the uniform composite of bimetallic selenides and N-doped carbon can effectively tune redox active sites,the stable 3D structure of Fe–Co–Se/NCs guarantees the structural stability and wettability of the electrolyte,and the uniform distribution of Fe–Co–S nanoparticles in size esuppresses the volume expansion and accelerates the electrochemical reaction kinetics.

关键词： potassium hydroxide assisted aqueous strategy bimetallic zeolitic imidazolate frameworks bimetallic selenide lithium-ion batteries long cycle performance

The Research of One Novel Cost-Sensitive Classification Algorithm

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Chinese Journal of Electronics 2018年第5期27卷 1015-1024页

作者： ZHOU Jingjing SUN Weifeng HAN Xiaomin LU Ruqiang zhang Yuanqi zhang Shenwei Zhejiang Gongshang University School of Software Dalian University of Technology

Assuming that misclassification costs between different categories are equal, traditional Graph based semi-supervised classification(GSSC) algorithms pursues high classification accuracy. In many practical problems, especially in the fields of finance and medicine,compared with global classification accuracy, less cost on global misclassification is more likely to be the most significant factor. We propose one novel cost-sensitive classification algorithm based on the local and global consistency, which utilizes the semi-supervised classification algorithms better, and ensures higher classification accuracy on the basis of reducing overall cost. Our improved algorithm may bring some problems due to unbalanced data account, so we introduce synthetic minority oversampling technique algorithm for further optimization. Experimental results of bank loans and medical problems verify the effectiveness of our novel classification algorithm.

关键词： Graph-based semi-supervised classification(GSSC) Cost-sensitive Rescale

A motion characteristics modeled angular position sensor by nonlinear transfer of differential capacitance for miniaturized scanning mirrors

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Microsystems & Nanoengineering 2023年第6期9卷 129-147页

作者： Songtao Liu Gaofei zhang Lingyun zhang Junya Wang Minghao Gong Zheng You Department of Precision Instrument Tsinghua UniversityBejing 100084China Key Laboratory of Smart Microsystem(Tsinghua University) Ministry of EducationBeijing 100084China State Key Laboratory of Precision Measurement Technology and Instruments Tsinghua UniversityBeijing 100084China School of Mechanical Science&Engineer Huazhong University of Science and TechnologyWuhan 430074China

In this paper,an angular position sensor(APS)designed for a resonant miniaturized scanning mirror(M-SM)is *** APS operates based on the principle of differential variable capacitance,significantly expanding the detectable bandwidth from a few hertz to several *** modeling the motion characteristics,the sampling rates of the biaxial scanning angles are 1473.6 times and 539.4 times higher than those of conventional ***,the motion characteristics model is presented as a simple harmonic motion,converting sampled capacitance into continuous ***,the nonparallel state of the M-SM and sensor is transformed into a parallel state through the space coordinate system ***,a 2D nonlinear angle transfer function is developed to convert the differential capacitance into an angle,thereby mitigating the nonlinear errors resulting from large *** an accuracy better than 0.014°,the measuring range expands from±0.5729°(±10 mrad)to±5.026°(±87 mrad).Additionally,the capturing mode and tracking mode are proposed to monitor real-time angular changes of the M-SM with an accuracy of 0.017°.High-precision APSs have enhanced beam pointing accuracy and resolution and can thereby be used to advance the development of laser components,including light detection and ranging(LiDAR).

关键词： capacitance angular nonlinear

The catalytic effect of bismuth for VO2+/VO2+and V3+/V2+redox couples in vanadium flow batteries

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Journal of Energy Chemistry 2017年第1期26卷 1-7页

作者： Xiaofei Yang Tao Liu Chi Xu Hongzhang zhang Xianfeng Li Huamin zhang Division of Energy Storage Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100039China Collaborative Innovation Center of Chemistry for Energy Materials(iChEM) Dalian 116023LiaoningChina

The effect of bismuth (Bi) for both VO2+/VO2+ and V3+/V2+ redox couples in vanadium flow batteries (VFBs) has been investigated by directly introducing Bi on the surface of carbon felt (CF). The results show that Bi has no catalytic effect for VO2+/VO2(+) redox couple. During the first charge process, Bi is oxidized to Bi3+ (never return back to Bi metal in the subsequent cycles) due to the low standard redox potential of 0.308 V (vs. SHE) for Bi3+/Bi redox couple compared with VO2+/VO2+ redox couple and Bi3+ exhibit no (or neglectable) electro-catalytic activity. Additionally, the relationship between Bi loading and electrochemical activity for V3+/V2+ redox couple was studied in detail. 2 wt% Bi-modified carbon felt (2%-BiCF) exhibits the highest electrochemical activity. Using it as negative electrode, a high energy efficiency (EE) of 79.0% can be achieved at a high current density of 160 mA/cm(2), which is 5.5% higher than the pristine one. Moreover, the electrolyte utilization ratio is also increased by more than 30%. Even the cell operated at 140 mA/cm(2) for over 300 cycles, the EE can reach 80.9% without obvious fluctuation and attenuation, suggesting excellent catalytic activity and electrochemical stability in VFBs. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.

关键词： Vanadium flow battery Bismuth Catalysis Electrochemical activity Energy efficiency