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Chinese Journal of Chemical Physics 2012年第6期25卷 703-707,I0004页

作者： Lin-chaoZhang Peng chen Zhang Hu chun-hua chen CAS Key Laboratory of Materials for Energy Conversion Department of Materials Science. and EnEi-neering University of Science and Technology of China Hefei 230025 China

Lithium-ion conductor Liz.3Alo.3Ti1.7（P04）3 with an ultrapure NASICON-type phase is syn- thesized by a 1,2-propylene glycol （1,2-PG）-assisted sol-gel method and characterized by differential thermal analysis-thermo gravimetric analysis, X-ray diffraction, scanning elec- tron microscopy, electrochemical impedance spectroscopy, and chronoamperornetry test. Due to the use of 1,2-PG, a homogeneous and light yellow transparent precursor solu- tion is obtained without the precipitation of Ti4＋ and A13＋ with PO43- Well crystallized Lil.3Alo.3Til.7（PO4）3 can be prepared at much lower temperatures from 850 ~C to 950 ~C within a shorter synthesis time compared with that prepared at a temperature above 1000 ~C by a conventional solid-state reaction method. The lithium ionic conductivity of the sintered pellets is up to 0.3 mS/cm at 50 ℃ with an activation energy as low as 36.6 k J/tool for the specimen pre-sintered at 700 ℃ and sintered at 850 ℃. The high conductivity, good chemi- cal stability and easy fabrication of the Li1.3Al0.3Ti1.7（PO4）a provide a promising candidate as solid electrolyte for all-solid-state Li-ion rechargeable batteries.

关键词： Lithium aluminum titanium phosphate Lithium-ion conductor NASICONelectrolyte Impedance spectroscopy

Synthesis and Crystal Structure of a Novel Manganese Coordination Polymer Constructed by 3,5-Dimethylbenzoic Acid with 4,4'-Bipyridine

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Chinese Journal of Structural Chemistry 2006年第10期25卷 1213-1216页

作者： ZHANG chun-hua chen Man-Sheng KUANG Dai-Zhi Department of Chemistry and Materials Science Hengyang Normal University Hengyang 421008 China

A novel manganese coordination polymer [Mn（L）2（bipy）]n （HL = 3,5-dimethylbenzoic acid, 4,4＇-bipy = 4,4＇-bipyridine） has been synthesized by a hydrothermal method. The molecular and crystal structures were determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group C2/c with a = 2.0996（8）, b = 1,1835（5）, c = 0.9958（4） nm, β = 110.161（5）°, V = 2,3229（16） nm^3, Z = 4, C28H26MnN2O4, Mr = 509.45, Dc= 1.457 g/cm^3,μ = 0.607 mm^-1, F（000） = 1060, Rim = 0.0566, R = 0.0334 and wR = 0.1078. In the crystal the manganese atom is six-coordinated by two nitrogen atoms from 4,4＇-bipy and four oxygen atoms from 3,5-dimethylbenzolate molecules, completing an octahedral geometry. The 4,4＇-bipy molecules bridge the infinite chain [Mn（L）2（bipy）]n to form a two-dimensional layer.

关键词： manganese coordination polymer hydrothermal synthesis crystal structure

The influences of wall Lorentz force and field Lorentz force on the cylinder drag reduction

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Acta Mechanica Sinica 2011年第5期27卷 668-674页

作者： Hui Zhang Bao-chun Fan Zhi-hua chen Yan-Ling Li Science and Technology on Transient Physics Laboratory Nanjing University of Science and Technology210094 Nanjing China

In this paper,the effects of Lorentz force on drag reduction for a circular cylinder have been studied experimentally and *** on its effects on drag reduction,the Lorentz force is found to be classified into two parts：one acts directly on the cylinder,named as the wall Lorentz force,and the other called the field Lorentz force acts on the fluid inside the boundary *** wall Lorentz force leads to the generation of a thrust,whereas the field Lorentz force results in drag *** the former dominates the drag variation,the drag would reduce accordingly and even turn into negative （thrust） with the application of Lorentz force.

关键词： Cylinder wake · Flow control · Lorentz force · Electromagnetic control

A Mutation of OSOTP 51 Leads to Impairment of Photosystem I Complex Assembly and Serious Photo-damage in Rice

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Journal of Integrative Plant Biology 2012年第2期54卷 87-98页

作者： Jian-Wei Ye Zi-Ying Gong chun-Guang chen hua-Ling Mi Gen-Yun chen National Key Laboratory of Plant Molecular Genetics Institute of Plant Physiology and Ecology Shanghai Institutes for Biological SciencesChinese Academy of Sciences Shanghai 200032 China

Gene expression in chloroplasts is regulated by many nuclear-encoded proteins. In this study, we isolated a rice （Oryza sativa subsp, japonica） mutant osotp51 with significant reduction in photosystem I （PSI）. The osotp51 is extremely sensitive to light and accumulates a higher level of reactive oxygen species. Its leaves are almost albino when grown at 40 ~mol photons/m2 per s. However, grown at 4 umol photons/m2 per s, osotp51 has a similar phenotype to the wild-type. 77K chlorophyll fluorescence analysis showed a blue shift in the highest peak emission from PSI in osotp51. In addition, the level of PSI and PSII dimer is dramatically reduced in osotp51. OSOTP 51 encodes a pentatricopeptide repeats protein, homologous to organelle transcript processing 51 in Arabidopsis. Loss-of-function OSOTP51 affects intron splicing of a number of plastid genes, particularly the ycf3 coding a protein involved in the assembly of PSI complex. OSOTP51 is functionally conserved in higher plants. The mutation of osotp51 indirectly leads to a widespread change in the structure and functions of PSI, results in severe photoinhibition, and finally dies, even when grown under very low light intensity.

关键词： Chloroplast photoprotection photosynthesis splicing ycf3

Nano-Li3V2（PO4）3/C Synthesized by Thermal Polymerization Method as Cathode Material for Lithium Ion Batteries

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Chinese Journal of Chemical Physics 2016年第6期29卷 699-702,I0001页

作者： Bin cheng Lian-sheng Jiao Zhong-feng Tang Sheng-jie Zhang Hong-li chen chun-hua chen CASKeyLaboratoryofMaterialsforEnergyConversions DepartmentofMaterialsScienceandEngineering&CollaborativeInnovationCenterofSuzhouNanoScienceandTechnologyUniversityofScienceandTechnologyofChinaHefei230026China DepartmentofChemistry HebeiNormalUniversityforNationalitiesChengde067000China

A nano-Li3V2（PO4）3/C powder was successfully prepared by a thermal polymerization method. The particle sizes of the intermediate product powder and the final product Li3V2（PO4）3 are all less than 200 nm. The carbon is partially coated on the surface of Li3V2（PO4）3 particles and the rest exists between particles with a total carbon content of 4.6wt%. This nano-Li3V2（PO4）3/C sample shows a discharge capacity of 124 mAh/g with-out capacity fading after 100 cycles at 0.1 C in the voltage rang of 3.0-4.3 V. Excellent rate performance is also achieved with a capacity of 80 mAh/g at 20 C in 3.0-4.3 V and 100 mAh/g at 10 C in 3.0-4.8 V. This study suggests that the thermal polymerization method is suitable to synthesize nano-Li3V2（PO4）3/C materials.

关键词： Lithium vanadium phosphate Thermal polymerization Nanoparticles Acrylic acid

Scale adaptive fitness evaluation‐based particle swarm optimisation for hyperparameter and architecture optimisation in neural networks and deep learning

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CAAI Transactions on Intelligence Technology 2023年第3期8卷 849-862页

作者： Ye‐Qun Wang Jian‐Yu Li chun‐hua chen Jun Zhang Zhi‐Hui Zhan School of Computer Science and Engineering South China University of TechnologyGuangzhouChina School of Software Engineering South China University of TechnologyGuangzhouChina Hanyang University AnsanSouth Korea

Research into automatically searching for an optimal neural network(NN)by optimi-sation algorithms is a significant research topic in deep learning and artificial ***,this is still challenging due to two issues:Both the hyperparameter and ar-chitecture should be optimised and the optimisation process is computationally *** tackle these two issues,this paper focusses on solving the hyperparameter and architecture optimization problem for the NN and proposes a novel light‐weight scale‐adaptive fitness evaluation‐based particle swarm optimisation(SAFE‐PSO)***,the SAFE‐PSO algorithm considers the hyperparameters and architectures together in the optimisation problem and therefore can find their optimal combination for the globally best ***,the computational cost can be reduced by using multi‐scale accuracy evaluation methods to evaluate ***,a stagnation‐based switch strategy is proposed to adaptively switch different evaluation methods to better balance the search performance and computational *** SAFE‐PSO algorithm is tested on two widely used datasets:The 10‐category(i.e.,CIFAR10)and the 100−cate-gory(i.e.,CIFAR100).The experimental results show that SAFE‐PSO is very effective and efficient,which can not only find a promising NN automatically but also find a better NN than compared algorithms at the same computational cost.

关键词： deep learning evolutionary computation hyperparameter and architecture optimisation neural networks particle swarm optimisation scale‐adaptive fitness evaluation

In vivo observation of cerebral microcirculation after experimental subarachnoid hemorrhage in mice

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Neural Regeneration Research 2018年第3期13卷 456-462页

作者： Xiao-mei Yang Xu-hao chen Jian-fei Lu Chang-man Zhou Jing-yan Han chun-hua chen Department of Human Anatomy and Embryology Peking University Health Science Center School of Basic Medical Sciences Peking University Health Science Center Tasly Microcirculation Research Center Peking University Health Science Center

Acute brain injury caused by subarachnoid hemorrhage is the major cause of poor prognosis. The pathology of subarachnoid hemorrhage likely involves major morphological changes in the microcirculation. However, previous studies primarily used fixed tissue or delayed injury models. Therefore, in the present study, we used in vivo imaging to observe the dynamic changes in cerebral microcirculation after subarachnoid hemorrhage. Subarachnoid hemorrhage was induced by perforation of the bifurcation of the middle cerebral and anterior cerebral arteries in male C57/BL6 mice. The diameter of pial arterioles and venules was measured by in vivo fluorescence microscopy at different time points within 180 minutes after subarachnoid hemorrhage. Cerebral blood flow was examined and leukocyte adhesion/albumin extravasation was determined at different time points before and after subarachnoid hemorrhage. Cerebral pial microcirculation was abnormal and cerebral blood flow was reduced after subarachnoid hemorrhage. Acute vasoconstriction occurred predominantly in the arterioles instead of the venules. A progressive increase in the number of adherent leukocytes in venules and substantial albumin extravasation were observed between 10 and 180 minutes after subarachnoid hemorrhage. These results show that major changes in microcirculation occur in the early stage of subarachnoid hemorrhage. Our findings may promote the development of novel therapeutic strategies for the early treatment of subarachnoid hemorrhage.

关键词： nerve regeneration subarachnoid hemorrhage microcirculation disturbance leukocyte adhesion albumin extravasation cerebral blood flow vasoconstriction early brain injury neural regeneration

Synthesis,Crystal Structure and Thermoanalysis of Complex of Zn(II) with Aminomethanesulfonic Acid-5-bromosalicylaldelyde Schiff Base

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Chinese Journal of Structural Chemistry 2006年第8期25卷 919-922页

作者： DENG Yi-Fang KUANG Dai-Zhi ZHANG chun-hua chen Man-Sheng PENG Yun-Lin YANG Ying-Qun LI Wei Department of Chemistry and Material Science Hengyang Normal University Hengyang 421008 China

The title complex [Zn（L）（phen）（CH3OH）] （L = C8H6BrO4NS, aminomethanesulfonic acid 5-bromo-salicylaldelyde schiff base; phen = 1,10-phenanthroline） has been synthesized and characterized by X-ray diffraction method. The crystal belongs to monoclinic, space group P21/c with a = 1.8712（3）, b = 1.38008（19）, c = 0.83685（12） nm, β = 97.791 （2）°, Mr = 569.72, V = 2.1411 （5） nm^3, Z= 4, Dc = 1.767 g/cm^3,μ = 3.151 mm^-1, F（000） = 1144, the final R = 0.0402 and wR = 0.0885. The central Zn（Ⅱ） is six-coordinated by one nitrogen and two oxygen atoms from the Schiff base, two nitrogen atoms from 1,10-phenanthroline and one oxygen from methanol to form a distorted octahedral coordination geometry.

关键词： zinc complex aminomethanesulfonic acid 5-bromo-salicylalddyde schiff base crystal structure thermal analysis

Pressure-induced anomalous insulating behavior in frustrated iridate La_(3)Ir_(3)O_(11)

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Chinese Physics B 2021年第6期30卷 547-551页

作者： chun-hua chen Yong-Hui Zhou Ying Zhou Yi-Fang Yuan Chao An Xu-Liang chen Zhao-Ming Tian Zhao-Rong Yang Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions High Magnetic Field LaboratoryChinese Academy of SciencesHefei 230031China Science Island Branch of Graduate School University of Science and Technology of ChinaHefei 230026China Institutes of Physical Science and Information Technology Anhui UniversityHefei 230601China School of Physics and Wuhan National High Magnetic Field CenterHuazhong University of Science and TechnologyWuhan 430074China High Magnetic Field Laboratory of Anhui Province Hefei 230031China

The geometrically frustrated iridate La_(3)Ir_(3)O_(11) with strong spin–orbit coupling and fractional valence was recently predicted to be a quantum spin liquid candidate at ambient conditions. Here, we systematically investigate the evolution of structural and electronic properties of La_(3)Ir_(3)O_(11) under high pressure. Electrical transport measurements reveal an abnormal insulating behavior rather than metallization above a critical pressure P_(c) ~ 38.7 GPa. Synchrotron x-ray diffraction(XRD)experiments indicate the stability of the pristine cubic KSbO_(3)-type structure up to 73.1 GPa. Nevertheless, when the pressure gradually increases across P_(c), the bulk modulus gets enhanced and the pressure dependence of bond length d_(Ir-Ir) undergoes a slope change. Consistent with the XRD data, detailed analyses of Raman spectra reveal an abnormal redshift of Raman mode and a change of Raman intensity around P_(c). Our results demonstrate that the pressure-induced insulating behavior in La_(3)Ir_(3)O_(11) can be assigned to the structural modification, such as the distortion of IrO_6 octahedra. These findings will shed light on the emergent abnormal insulating behavior in other 5 d iridates reported recently.

关键词： high pressure 5d iridates semimetal–insulator transition crystal structure

Goal-Oriented Control Systems(GOCS):From HOW to WHAT

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 816-819页

作者： Wen-hua chen the Department of Aeronautical and Automotive Engineering Loughborough UniversityLeicestershireLE113TUU.K.

Brief:New control theory is required to underpin safe design and deployment of future highly automated systems to deal with uncertain environments and complicated tasks,enabled by AI and other advanced ***-Oriented Control Systems offer potential to transform the control system design from currently instructing a control system how to perform a task to specifying what is to be achieved.

关键词： automated instru system