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A New PAA Sol-Gel Method to Synthesis the Spinel LiMn_2._4 Material for Li-ion Battery

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wuhan university Journal of Natural {2. 2002年第1期7卷 97-101页

作者： zhan hui, zhou {2.-hong  college of chemistry and Molecular sciences, wuhan university, wuhan 43.072. hubei, china college of chemistry and Molec. Sci. Wuhan University Wuhan 430072 Hubei China

A PAA sol-gel method, which is based on the chelate effect of PAA polymer, was developed for the synthesis of the spinel LiMn 2. 4 material. The pyrolysis process of the PAA-nitrate mixture precursor was investigated by TG and DTA analysis. It is found that the structure and electrochemical properties of the material are sensitive to the atmosphere employed in the synthesis process. Preliminary results show that the material thus prepared has a good electrochemical performance even at high charge and discharge current.

关键词： sol-gel PAA spinel material

Dislocation density-me diate d creep ageing behavior of an Al-Cu-Li alloy

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Journal of Materials Science & Technology 2024年第7期174卷 204-217页

作者： Chang zhou Lihua zhan Chun{2. Liu Ming{2. Huang college of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China State Key Laboratory of Precision Manufacturing for Extreme Service Performance Central South UniversityChangsha 410083China Light Alloys Research Institute Central South UniversityChangsha 410083China

Creep aging is well-known to be a time-dependent,coupled process of deformation and precipitation strengthening for age-hardening *** existing mechanisms are mainly attributed to those interac-tions between atomic diffusion and dislocation ***,an understanding of the relationship between dislocation density and a special multistage creep behavior,i.e.,double steady creep feature,is still far *** we investigate the effect of various dislocation density levels on such an abnormal multistage creep of an Al-Cu-Li *** find that the increased dislocation densities enable an apparent time decrease(from 6.2.h to 0.8 h)of their first steadyⅡ-*** yield strength of post-aged sam-ples increases from 42..0 MPa to 580.0 MPa while the corresponding elongation decreases from 12.3%to 7.3%for the creep-aged samples#1 to#*** results also reveal that a great difference in dislocation configuration,tailored by various density levels,results in varying creep processes of theⅡ-*** stage is closely related to the nucleation and early growth of T_(1)*** number densities(maximum:2.9×10^(19)m^(-3))and the average length(maximum:2..3 nm)of T_(1)precipitates are much smaller than those of the stable peak-aged T_(1)phases,suggesting that creepⅡ-stage of all three creep-aged samples is dominant by the nucleation and initial growth of those T_(1)*** study provides valuable insights into the dislocation density-mediated creep deformation of an Al-Cu-Li alloy.

关键词： Dislocation density Al-Cu-Li alloy Creep ageing T_(1)precipitation

Electrochemical Studies of Glutathione Monolayer Assembled on A Polycrystalline Gold Electrode

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wuhan university Journal of Natural {2. 2002年第1期7卷 102-106页

作者： Fang Cheng, zhou Xing-yao  college of {2. and Molecular sciences, wuhan university, wuhan 43.072. hubei, china wuhan university College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

The glutathione (GSH) monolayer and complex monolayer of GSH-metallic ion on polycrystalline gold electrode were studied by using K3Fe(CN)6 as the redox probe. As for the GSH monolayer, it was found that the metallic ions could open the ion-gate in the monolayer dramatically in the order La3+> Pb2.>>Ba2.>Ca2. whereas Zn2. ion closed the ion-gate. The complexes of GSH-metallic ions were capable of self-assembling the different kind of monolayer. All the differences were related to the structural configuration of the anchored GSH molecule, which changed with different metallic ions or pH.

关键词： glutatione monolayer complex voltammetry and ac impedance

Polymer-supported chiral palladium-based complexes as efficient heterogeneous catalysts for asymmetric reductive Heck reaction

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Green Synthesis and Catalysis

Green Synthesis and Catalysis 2024年第2期5卷 102-107页

作者： hui zhang Bing Xu Liejin {2. zhan-Ming zhang Junliang zhang college of Marine Ecology and Environment Shanghai Ocean University999 Hucheng Ring RoadShanghai 201306China Department of chemistry Fudan University2005 Songhu RoadShanghai 200438China Graduate School of Pharmaceutical sciences Tohoku UniversitySendai 980-8578Japan Fudan zhangjiang Institute Shanghai 201203China

Heterogeneous asymmetric catalysis is an important strategy for the industrial production of chiral ***,we reported a polymer-bound Xu-Phos-derived palladium catalyst that shows good performance in heterogeneous asymmetric reductive Heck reaction of allyl aryl *** heterogeneous catalyst was easily prepared by efficient immobilization of the sulfonamide phosphine ligand(Xu-Phos)in the cross-linked polystyrene via copolymerization,and exhibits similar catalytic activity and enantioselectivity to that of the homogeneous ***,the heterogeneous catalyst system is proved to be easily recovered and reused several times without losing catalytic activity obviously.

关键词： Heterogeneous catalysis Recoverability Palladium Hydroarylation Asymmetric catalysis

Recent advances in Fe-N-C-and Co-N-C-based materials as bifunctional electrocatalysts for oxygen reduction and oxygen evolution

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Science china chemistry 2024年第4期67卷 1137-1160页

作者： hui-Min Xu hong-Rui Zhu Chen-Jin Huang Zhi-Jie {2.g Ting-Yu Shuai Qi-Ni {2. Gao-Ren Li college of Materials Science and Engineering Sichuan UniversityChengdu 610065China

Fe-nitrogen-carbon(Fe-N-C)-and Co-nitrogen-carbon(Co-N-C)-based electrocatalysts have been widely concerned because of their high OER/ORR activity,low metal cost,and simple *** exploration of Fe-N-C and Co-N-C single atombased catalysts with high activity and stability to overcome the slow kinetics of oxygen reduction and oxygen evolution reactions is also the key to the development of efficient electrolytic water,fuel cells,and rechargeable metal-air ***-N-C and Co-N-C single atom-based electrocatalysts have the advantages of a high utilization rate of metal atoms and high electrocatalytic activity,and are ideal catalysts for promoting electrochemical energy conversion and *** general principles of designing Fe-N-C and Co-N-C single atom-based electrocatalysts are reviewed in this ***,the strategies to improve the bifunctional catalytic activity and stability are ***,the challenges and prospects of Fe-N-C and Co-N-C single atom-based catalysts are well *** review will provide a reference for the directed optimization of Fe-N-C and Co-N-C single atom-based catalysts.

关键词： Fe-N-C Co-N-C single atom bifunctional oxygen electrocatalysts

Reduced-complexity multiple parameters estimation via toeplitz matrix triple iteration reconstruction with bistatic MIMO radar

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Chinese Journal of Aeronautics 2024年第7期37卷 482-495页

作者： Chenghong zhan Guoping HU Junpeng SHI Fangzheng ZHAO Hao {2. Graduate college Air Force Engineering UniversityXi’an 710051China Air and Missile Defense college Air Force Engineering UniversityXi’an 710051China college of Electronic Countermeasure National University of Defense TechnologyHefei 230037China Beijing Aeronautical Technology Research Center Beijing 100076China

In this advanced exploration, we focus on multiple parameters estimation in bistatic Multiple-Input Multiple-Output(MIMO) radar systems, a crucial technique for target localization and imaging. Our research innovatively addresses the joint estimation of the Direction of Departure(DOD), Direction of Arrival(DOA), and Doppler frequency for incoherent targets. We propose a novel approach that significantly reduces computational complexity by utilizing the TemporalSpatial Nested Sampling Model(TSNSM). Our methodology begins with a multi-linear mapping mechanism to efficiently eliminate unnecessary virtual Degrees of Freedom(DOFs) and reorganize the remaining ones. We then employ the Toeplitz matrix triple iteration reconstruction method, surpassing the traditional Temporal-Spatial Smoothing Window(TSSW) approach, to mitigate the single snapshot effect and reduce computational demands. We further refine the highdimensional ESPRIT algorithm for joint estimation of DOD, DOA, and Doppler frequency, eliminating the need for additional parameter pairing. Moreover, we meticulously derive the Cramér-Rao Bound(CRB) for the TSNSM. This signal model allows for a second expansion of DOFs in time and space domains, achieving high precision in target angle and Doppler frequency estimation with low computational complexity. Our adaptable algorithm is validated through simulations and is suitable for sparse array MIMO radars with various structures, ensuring higher precision in parameter estimation with less complexity burden.

关键词： MIMO Radar Multipleparameters estimation Temporal-spatial Nested Sampling Multi-linear mapping mechanism Toeplitz matrix triple iteration reconstruction Reduce computational complexity

Water and other volatiles on Mars

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National Science Review 2024年第06期11卷 12-14页

作者： Sen Hu Yubing Gao zhan zhou Liang Gao Yangting Lin Key Laboratory of the Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of Sciences college of Earth and Planetary sciences University of Chinese Academy of Sciences

Mars, the intriguing red planet, is one of the planets most similar to the Earth in our solar system. It is widely accepted that Mars could have had a warm and wet climate in its early history supported by numerous lines of evidence, e.g. topography, canyons, outflow channels, presence of phyllosilicates and evaporative salts,sedimentary formation, and many others (e.g.[1]), and thus Mars is believed to once have a potentially habitable environment which could be able to supply fundamental conditions for the evolution of potential lives.

关键词： ISOTOPIC COMPOSITION MARTIAN ATMOSPHERE SUBSURFACE WATER ABUNDANCE TISSINT H2. CO2

Research on the prognostic value of adjusting intraperitoneal threedimensional quality evaluation mode in laparoscopic cholecystectomy patients

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World Journal of Gastrointestinal Surgery 2024年第4期16卷 1078-1086页

作者： Yuan zhou zhan-Qing Chen Operating Room Lianyungang Hospital of Traditional Chinese MedicineLianyungang 222000Jiangsu ProvinceChina Operating Room The Second People's Hospital of Lianyungang Affiliated to Kangda College of Nanjing Medical UniversityLianyungang 222000Jiangsu ProvinceChina

BACKGROUND Benign gallbladder diseases have become a high-prevalence condition not only in china but also *** main types of benign gallbladder diseases include gallbladder polyps,acute and chronic cholecystitis,and gallstones,with gallstones being the most common,accounting for over 70%of *** the mortality rate of benign gallbladder diseases is low,they carry obvious potential *** have shown that an increased incidence of benign gallbladder diseases can increase the risk of cardiovascular diseases and gallbladder cancer,resulting in a substantial disease burden on patients and their *** To assess the medical utility of the Configuration-Procedure-Consequence(CPC)three-dimensional quality evaluation model in modulating the prognosis of laparoscopic cholecystectomy *** A total of 98 patients who underwent laparoscopic cholecystectomy in our hospital from February 2.2. to January 2.2. were selected as the *** to the random number table method,they were divided into a study group and a control group,with 49 patients in each *** control group received routine perioperative care,while the study group had the addition of the CPC three-dimensional quality *** postoperative recovery-related indicators(time to first flatus,time to oral intake,time to ambulation,hospital stay),stress indicators(cortisol and adrenaline levels),distinctions in anxiety and RESULTS The time to first flatus,time to oral intake,time to ambulation,and hospital stay of the study group patients were obviously lower than those of the control group patients,with statistical significance(P0.05).However,on the 3rd day after surgery,the cortisol and adrenaline leve

关键词： Configuration-Procedure-Consequence Three-dimensional quality evaluation Laparoscopic Cholecystectomy Recovery process Anxiety and depression Complications

Surface Films Formed on SnO_2.Anode in Lithium Secondary Batteries by FTIR Spectroscopy

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Journal of wuhan university of Technology(Materials Science) 2008年第5期23卷 662-665页

作者：黄峰 hubei Refractories and High-temperature Ceramics Key Laboratory Wuhan University of Science and Technology

The chemical composition of the passivating layer formed on nano SnO2.anodes in 1 M LiClO4＋（ethylene carbonate）EC ＋（dimethyl carbonate）DMC at different charge/discharge states in lithium secondary batteries was studied using extra reflectance FTIR spectra. Results show that solvent decomposition reaction that generally occurs on the surface of carbon and alkali metal electrodes also takes place on nano-SnO2.anode, and the major constituent of the passivating layer is Li2.O3 and ROCO2.i. Formation of the passivating layer would certainly lead to the irreversible capacity loss.

关键词： nano-SnO2.anode lithium rechargeable batteries FTIR passivating layer