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Chinese Journal of Structural Chemistry 2014年第10期33卷 1527-1532页

作者：李薇李昶红李衡峰谭雄文 School of Materials science and Engineering Central South University Department of Chemistry and Materials science Hengyang Normal University Department of Chemical Engineering hunan Institute of Technology

A new copper complex 2{Cu（C10H8N2）[C8H11O2（COO）]（H2O）3}·（H2O）5 with bicycle[2.2.1]hept-2-en-5,6-dicarboxylic acid（H2L） [C7H8（COOH）2], basic copper carbonate and 2,2＇-bipyridine has been synthesized in the mixed solvents of methanol and water. It crystallizes in the triclinic system, space group P1, with a = 7.4626（5）, b = 11.9779（8）, c = 12.9841（8）A, α = 109.7040（10）, β = 98.7550（10）, γ = 90.6240（10）°, V = 1077.50（12）A3, Dc = 1.538 g/cm^3, Z = 1, F（000） = 520, GOOF = 1.065, R = 0.0360 and wR = 0.0950. The copper ion is coordinated with four oxygen atoms from one H2 L molecule and three water molecules together with two nitrogen atoms from the 2,2＇-bipyridine molecule, forming a distorted octahedral coordination geometry. The thermal stability and electrochemical properties were also studied.

关键词： copper(II) complex crystal structure properties analysis

Co-doped graphene edge for enhanced N2-to-NH3 conversion

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Journal of Energy Chemistry 2020年第9期29卷 322-327,I0010页

作者： Zengxi Wei Yuezhan Feng Jianmin Ma School of Physics and Electronics Hunan UniversityChangsha 410082HunanChina Key Laboratory of Materials Processing and Mold(Zhengzhou University) Ministry of EducationZhengzhou UniversityZhengzhou 450002HenanChina

N2 fixation in atmosphere is an important issue in modern *** an ideal electrochemical nitrogen reduction reaction(NRR)catalyst to overcome the sluggish reaction kinetic and ultralow selectivity is still the significant ***,we screened the potential catalyst to accelerate N2 fixation by designing the single transition metal(TM)atoms(Ti,V,Cr,Mn,Fe,Co,Ni,Cu,Zn,Mo,W,Ru and Rh)supported on the edge of *** calculations revealed that the Co atom supported on the graphene edge could selectively stabilize*N2 H species and destabilize*NH2 species,leading to the highest catalytic activity and selectivity for N2 fixation at the ambient *** addition,the enzymatic mechanism of eNNR have the lowest overpotential of 0.72 *** theoretical work will give a new perspective to design an available catalyst for NRR.

关键词： conditions. chemistry. catalyst

Fast solution to the free return orbit's reachable domain of the manned lunar mission by deep neural network

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Journal of Systems Engineering and Electronics 2024年第2期35卷 495-508页

作者： YANG Luyi LI Haiyang ZHANG Jin ZHU Yuehe College of Aerospace science and Engineering National University of Defense TechnologyChangsha 410073China China Astronauts Research and Training Center Beijing 100094China hunan Key Laboratory of Intelligent Planning and Simulation for Aerospace Missions Changsha 410073China

It is important to calculate the reachable domain(RD)of the manned lunar mission to evaluate whether a lunar landing site could be reached by the spacecraft. In this paper, the RD of free return orbits is quickly evaluated and calculated via the classification and regression neural networks. An efficient databasegeneration method is developed for obtaining eight types of free return orbits and then the RD is defined by the orbit’s inclination and right ascension of ascending node(RAAN) at the perilune. A classify neural network and a regression network are trained respectively. The former is built for classifying the type of the RD, and the latter is built for calculating the inclination and RAAN of the RD. The simulation results show that two neural networks are well trained. The classification model has an accuracy of more than 99% and the mean square error of the regression model is less than 0.01°on the test set. Moreover, a serial strategy is proposed to combine the two surrogate models and a recognition tool is built to evaluate whether a lunar site could be reached. The proposed deep learning method shows the superiority in computation efficiency compared with the traditional double two-body model.

关键词： manned lunar mission free return orbit reachable domain(RD) deep neural network computation efficiency

Recent advances in alloy-based anode materials for potassium ion batteries

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Rare Metals 2020年第9期39卷 970-988页

作者： Shi-Han Qi Ji-Wei Deng Wen-Chao Zhang Yue-Zhan Feng Jian-Min Ma State Key Laboratory of High-Performance Complex Manufacturing College of Mechanical and Electrical EngineeringCentral South UniversityChangsha 410083China School of Physics and Electronics Hunan UniversityChangsha 410082China Institute for Superconducting and Electronic Materials(ISEM) School of MechanicalMaterialsMechatronics&Biomedical EngineeringFaculty of Engineering and Information SciencesUniversity of WollongongWollongongNSW 2500Australia Key Laboratory of Materials Processing and Mold(Zhengzhou University) Ministry of EducationZhengzhou UniversityZhengzhou 450002China

Potassium ion batteries(PIBs)are regarded as one of promising low-cost energy storage *** long cycle life and high energy density has been considered as important tasks for developing high-performance *** alloy-based anodes for PIBs have attracted great attentions because of their high theoretical capacity and relatively low operating *** this review,the latest advance in the related alloy-based anodes was ***,the correlations among the morphology and potassium storage performance,phase transition mechanisms,the formation of solid electrolyte interphases and ionic transport kinetics are critically *** is expected that this review will provide meaningful guidance and possible pathways for the developments of alloy-based anodes for PIBs.

关键词： Potassium ion batteries Anode Alloy-based alloys Performance Nanostructures

Three-dimensional hierarchically porous nitrogen-doped carbon from water hyacinth as selenium host for high-performance lithium-selenium batteries

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Rare Metals 2022年第10期41卷 3432-3445页

作者： Wei-Na Deng Yan-Hua Li Di-Fa Xu Wei Zhou Kai-Xiong Xiang Han Chen hunan Key of Laboratory of Applied Environmental Photocatalysis Changsha UniversityChangsha410022China School of Metallurgy and Materials Engineering Hunan University of TechnologyZhuzhou412007China

Hierarchically porous nitrogen-doped carbon(HPNC) with interconnected micro-,meso-,and macropores was generated from KOH and urea etching as a carbon scaffold to infuse *** this structure,micropores confine Se as single-chain molecules,preventing the generation of higher-order polyselenides,the mesopores provide effective pathways for electrolyte diffusion and ion transport and offer sufficient void space to accommodate the volume change of Se upon lithiation/delithiation,and the doped nitrogen improves the electrical conductivity of HPNC and increases the utilization of *** applied as a scaffold for Se in a lithium-selenium battery,the Se/HPNC cathode with a large Se content of 67.6 wt% maintains a high discharge capacity of 410 mAh·g^(-1) at the 500 th cycle at1.0 C,and it demonstrates a discharge capacity as high as371 mAh·g^(-1) even at a high current density of 5.0 ***,when the current density returns to 0.2 C,the discharge capacity recovers to 527 mAh·g^(-1) with a capacity retention rate of 90.5% for the first 0.2 C,indicating the excellent structural stability of *** has significant potential for application in energy storage systems.

关键词： Hierarchically porous carbon Nitrogen-doped carbon Li-Se batteries Electrochemical performances

Simulation of urban expansion using geographical similarity transition rules and neighbourhood sizes

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Journal of Geographical sciences 2024年第7期34卷 1394-1414页

作者： LI Yinqi AN Yue ZHOU Zhou REN Hui TAN Xuelan College of Resources Hunan Agricultural UniversityChangsha410128China College of Geographical sciences Hunan Normal UniversityChangsha410081China

Most existing cellular automata(CA)models impose strict requirements on the number and spatial distribution of *** makes it a challenge to capture spatial heterogeneity in urban dynamics and meet the modeling needs of large and complex geographic *** paper presents a CA model based on geographically optimal similarity(GOS)transition rules and similarly sized neighborhoods(SSN).By comparing the similarity in geographical configuration between samples and predicted points,the model enables a comprehensive characterization of the driving mechanism behind urban expansion and its self-organizing *** helps to mitigate the impact of sample selection and assumptions about spatial stationarity on simulation *** performance of GOS-SSN-CA simulation was tested by taking the urban expansion in the Changsha-Zhuzhou-Xiangtan urban agglomeration in China as an *** results show that GOS can derive more accurate and reliable urban transition rules with fewer samples,thereby significantly reducing spatial prediction errors compared with logistic ***,SSN selects different neighborhood sizes to represent the difference between the local self-organizing range and surrounding cells,thus further improving the simulation accuracy and restricting urban expansion ***,GOS-SSN-CA effectively characterizes the geographical similarity of urban expansion,improves simulation accuracy while constraining the urban expansion form,and enhances the practical application value of CA.

关键词： urban growth cellular automata geographic similarity model optimization spatial nonstationarity

Promoted CO2 electroreduction over indium-doped SnP3: A computational study

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Journal of Energy Chemistry 2020年第9期29卷 1-6,I0001页

作者： Yuefeng Zhang Wenchao Zhang Yuezhan Feng Jianmin Ma School of Physics and Electronics Hunan UniversityChangsha 410082HunanChina Institute for Superconducting and Electronic Materials(ISEM) School of MechanicalMaterialsMechatronics&Biomedical EngineeringFaculty of Engineering and Information SciencesUniversity of WollongongNSW 2500Australia Key Laboratory of Materials Processing and Mold(Zhengzhou University) Ministry of EducationZhengzhou UniversityZhengzhou 450002HenanChina

It is generally considered that the hydrogenation of CO2 is the critical bottleneck of the CO2 *** this work,with the aid of density functional theory(DFT)calculations,the catalytic hydrogenation of CO2 molecules over Indium-doped SnP3 catalyst were systematically *** doping with indium(In)atom,the energy barrier of CO2 protonation is reduced and OCHO*species could easily be *** is mainly due to the p orbital of In exhibits strong hybridization with the p orbital of O,indicating that there is a strong interaction between OCHO*and In-doped SnP3 *** a result,In-doped SnP3 possesses high-efficiency and high-selectivity for converting CO2 into HCOOH with a low limiting potential of-0.17 *** findings will offer theoretical guidance to CO2 electroreduction.

关键词： CO2 electroreduction SnP3 Indium metal doping Formic acid First principles

Identification of Denatured Biological Tissues Based on Improved Variational Mode Decomposition and Autoregressive Model during HIFU Treatment

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Computer Modeling in Engineering & sciences 2022年第3期130卷 1547-1563页

作者： Bei Liu Xian Zhang College of Mathematics and Physics Hunan University Arts and ScienceChangde415000China Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of EducationSchool of Geosciences and Info-physicsCentral South UniversityChangsha410083China

During high-intensity focused ultrasound(HIFU)treatment,the accurate identification of denatured biological tissue is an important practical *** this paper,a novel method based on the improved variational mode decomposition(IVMD)and autoregressive(AR)model was proposed,which identified denatured biological tissue according to the characteristics of ultrasonic scattered echo signals during HIFU ***,the IVMD method was proposed to solve the problem that the VMD reconstruction signal still has noise due to the limited number of intrinsic mode functions(IMF).The ultrasonic scattered echo signals were reconstructed by the IVMD to achieve ***,the AR model was introduced to improve the recognition rate of denatured biological *** AR model order parameter was determined by the Akaike information criterion(AIC)and the characteristics of the AR coefficients were ***,the optimal characteristics of the AR coefficients were selected according to the results of receiver operating characteristic(ROC).The experiments showed that the signal-to-noise ratio(SNR)and root mean square error(RMSE)of the reconstructed signal obtained by IVMD was better than those obtained by variational mode decomposition(VMD).The IVMD-AR method was applied to the actual ultrasonic scattered echo signals during HIFU treatment,and the support vectormachine(SVM)was used to identify the denatured biological *** results show that compared with sample entropy,information entropy,and energy methods,the proposed IVMD-AR method can more effectively identify denatured biological *** recognition rate of denatured biological tissue was higher,up to 93.0%.

关键词： HIFU ultrasonic scattered echo signals IVMD AR model

Characteristics of liver on magnetic resonance diffusion-weighted imaging:Dynamic and image pathological investigation in rabbit liver VX-2 tumor model

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World Journal of Gastroenterology 2008年第25期14卷 3997-4004页

作者： You-Hong Yuan En-Hua Xiao Jian-Bin Liu Zhong He Ke Jin Cong Ma Jun Xiang Jian-Hua Xiao Wei-Jian Chen Department of Radiology Hunan Province People's Hospital Changsha 410005 HunanProvince China Departmentof Radiology the Second Xiangya Hospital Central SouthUniversity Changsha 410005 Hunan Province China Department of Pathology HunanProvince Children's Hospital Changsha 410005 HunanProvince China Department of Epidemiology Center forDisease Control of Hunan Province Changsha 410005 HunanProvince China

AIM： To investigate dynamical and image pathological characteristics of the liver on magnetic resonance （MR） diffusion-weighted imaging （DWI） in the rabbit VX-2 tumor model. METHODS： Forty New Zealand rabbits were included in the study and VX-2 tumor piece was implanted intrahepatically. Fifteen animals received two intrahepatic implantations while 25 had one intrahepatical implantation. DWI, T1- and T2-weighted of magnetic resonance imaging （MRI） were carried out on the 7th and the 14th d after implantation and DWI was conducted, respectively on the 21th d. Ten VX-2 tumor samples were studied pathologically. RESULTS： The rate of lump detected by DWI, TlWI and T2WI was 78.7%, 10.7% and 53.5% （X^2 =32.61, P 〈 0.001） on the 7th d after implantation and 95.8%, 54.3% and 82.9% （X^2 = 21.50, P 〈 0.001） on the 14th d. The signal of most VX-2 tumors on DWI was uniform and it was equal diffusion coefficient （ADC）. did not decrease on the 7th on the map of apparent The signal of VX tumors d after implantation, most of them slowly growing during the week following implantation without significant cell dying within the tumor. VX-2 tumors grew increasingly within 14 d after implantation but the signal of most VX-2 tumors on DWI or on the map of ADC was uniform or uneven and ADC of VX tumors decreased obscurely or slightly because tumor necrosis was still not obvious. On the 21th d after implantation, the signal of most VX-2 tumors on DWI or on the map of ADC was uneven because tumor necrosis was evident and ADC of VX-2 tumor necrotic areas decreased. The areas of viable cells in VX-2 tumors manifested a high signal on DWI and a low signal on the map of ADC. The areas of dead cells or necrosis in VX-2 tumors manifested low signals on DWI and low, equal or high signals on the map of ADC but they manifested high signals on DWI and on the map of ADC at the same time when the areas of necrotic tumor became liquefied or cystic. The border of tumors on DWI appeared gradually disti

关键词： Liver VX-2 tumor Diffusion-weightedimaging Apparent Diffusion Coefficient Rabbit

Preparation of anodic films on 2024 aluminum alloy in boric acid-containing mixed electrolyte

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中国有色金属学会会刊：英文版 2008年第4期18卷 825-830页

作者：马淞江罗鹏周海晖付超鹏旷亚非 College of Chemistry and Chemical Engineering Hunan University of Science and TechnologyXiangtan 411201China College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410082China

The anodizing oxidation process on 2024 aluminum alloy was researched in the mixed electrolyte with the composition of 30 g/L boric acid, 2 g/L sulfosalicylic acid and 8 g/L phosphate. The results reveal that the pre-treatment and the composition of the mixed electrolyte have influence on the properties of the films and the anodizing oxidation process. Under the condition of controlled potential, the anodizing oxidation current—time response curve displays "saddle" shape. First, the current density reaches a peak value of 8-20 A/dm2 and then decreases rapidly, finally maintains at 1-2 A/dm2. The film prepared in the mixed electrolyte is of porous-type with 20 nm in pore size and 500 μm-2 in porosity. Compared with the conventional anodic film obtained in sulfuric acid, the pore wall of the porous layer prepared in this work is not continuous, which seems to be deposited by small spherical grains. This porous structure of the anodic film may result from the characteristics of the mixed electrolyte and the special anodizing oxidation process. The surface analysis displays that the anodic film is amorphous and composed of O, Al, C, P, S, Si and no copper element is detected.

关键词： 2024铝合金硼酸混合电解液阳极电镀阳极薄膜