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Promoting the methanol oxidation catalytic activity by introducing surface nickel on platinum nanoparticles

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Nano Research 2018年第4期11卷 2058-2068页

作者： Siqi Lu huiming li Jingyao Sun Zhongbin Zhuang State Key Lab of Organic-Inorganic Composites Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing Key Lab of Energy Environmental Catalysis Beijing University of Chemical Technology Beijing 100029 China

High performance methanol oxidation reaction （MOR） catalysts are critical to the performance of attractive, direct methanol fuel cells. Here, we use surface controlled PtNi alloy nanoparticles as model catalysts to study the MOR mechanism and give further guidance to the design of new high performance MOR catalysts. The enhanced MOR activity of PtNi alloy was mainly attributed to the enhanced OH adsorption owing to surface Ni sites. This suggests that the MOR undergoes the Langmuir-Hinshelwood mechanism, whereby adsorbed CO is removed with the assistance of adsorbed OH. Within the PtNi catalyst, Pt provides methanol adsorption sites （in which methanol is converted to adsorbed CO） and Ni provides OH adsorption sites. The optimized Pt-Ni ratio for MOR was found to be 1：1. This suggests that bifunctional catalysts with both CO and OH adsorption sites can lead to highly active MOR catalysts.

关键词： methanol oxidation reaction (MOR) Pt alloy catalysts surface structure OH adsorption

Improving strength-ductility synchronously of Electron beam welded Ti600/Ti2AlNb joint through isothermal forging

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Progress in Natural Science:Materials International 2024年第3期34卷 532-539页

作者： Yongqiang Zhang Xiangyi Xue Guoming Zheng Jingli Zhang huiming li Shewei Xin State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi'an Qin Ti Intelligent Manufacturing Technologies Co.Ltd. Northwest Institute for Nonferrous Metal Research Xi'an University of Science and Technology Avic Xi'an Aircraft Industry Group Company Ltd.

Different alloys can be flexibly combined to meet the performance needs of different parts of the compressor disc by welding process. However, achieving a good combination of dissimilar alloys with different mechanical properties has always been a research difficulty. In this work, a Ti600/Ti2AlNb joint was fabricated through electron beam welding and an isothermal forging was used to optimized its microstructure and mechanical performance. The isothermal forging process increases the ultimate tensile strength（UST） and yield strength（YS）of the Ti600/Ti2AlNb joint by ～18 %, while ～2.5 times the ductility. It is indicated that before forging, the Ti600/Ti2AlNb joint exhibits a much lower strength than that of Ti600 matrix, whereas the opposite is true after isothermal forging. The isothermal forging broken the coarse columnar grains of Ti600/Ti2AlNb joint and render to an equiaxed B2 structure in which the acicular α2and O phase are precipitated, resulting a synchronous enhancement of strength and ductility. This work may pave an effective routine for improving the comprehensive mechanical properties of dissimilar metal welding joint.

关键词： Electron beam welding Isothermal forging Mechanical performance Ti600/Ti2AlNb joint

U-Pb zircon age of the foliated garnet-bearing granites in western Dabie Mountains,Central China

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Chinese Science Bulletin 2001年第19期46卷 1657-1660页

作者： ZHANG Hongfei ZHONG Zengqiu GAO Shan ZHANG Benren li huiming Faculty of Earth Sciences China University of GeosciencesWuhan 430074China Department of Geology Northwest UniversityXi’an 710069China Tianjin Institute of Geology and Mineral Resource Tianjin 300170China

U-Pb zircon dating on two foliated garnet-bearing granite samples in the western Dabie ultra-high-pressure (UHP) metamorphic unit yields concordant ages of (234±4) Ma and (227±5) Ma, respectively. These ages, following the UHP peak metamorphism, represent the magma emplacement ages for the foliated garnet-bearing granites. This, for the first time, shows that there are the Triassic granites in the Dabie Mountains. The foliated garnet-bearing granites resemble A-type granite in geochemical characteristics, indicating that they were formed in exten-sional geodynamic setting. The magma formation reflects a reheating event in the Dabie orogenic belt and it enhances the transfer of tectonic regime from collision into extension and promotes the rapid exhumation into lower crust for the UHP metamorphic rocks.

关键词： Dabie orogenic belt foliated garnet-bearing granite U-Pb zircon age post-collisional granite.

Affine formation tracking control of unmanned aerial vehicles

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Frontiers of Information Technology & Electronic Engineering 2022年第6期23卷 909-919页

作者： huiming li Hao CHEN Xiangke WANG College of Intelligence Science and Technology National Uniuersity of Defense TechnologyChangsha 410073China

The affine formation tracking problem for fixed-wing unmanned aerial vehicles(UAVs)is considered in this paper,where fixed-wing UAVs are modeled as unicycle-type agents with asymmetrical speed constraints.A group of UAVs are required to generate and track a time-varying target formation obtained by affinely transforming a nominal *** handle this problem,a distributed control law based on stress matrix is proposed under the leader-follower control *** is proved,theoretically,that followers can converge to the desired positions and achieve affine transformations while tracking diverse ***,a saturated control strategy is proposed to meet the speed constraints of fixed-wing UAVs,and numerical simulations are executed to verify the effectiveness of our proposed affine formation tracking control strategy in improving maneuverability.

关键词： Affine formation Fixed-wing unmanned aerial vehicles Multi-agent system

Aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders:progress of experimental models based on disease pathogenesis

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Neural Regeneration Research 2025年第2期20卷 354-365页

作者： li Xu huiming Xu Changyong Tang Department of Neurology The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong ProvinceChina

Neuromyelitis optica spectrum disorders are neuroinflammatory demyelinating disorders that lead to permanent visual loss and motor *** date,no effective treatment exists as the exact causative mechanism remains ***,experimental models of neuromyelitis optica spectrum disorders are essential for exploring its pathogenesis and in screening for therapeutic *** most patients with neuromyelitis optica spectrum disorders are seropositive for IgG autoantibodies against aquaporin-4,which is highly expressed on the membrane of astrocyte endfeet,most current experimental models are based on aquaporin-4-IgG that initially targets *** experimental models have successfully simulated many pathological features of neuromyelitis optica spectrum disorders,such as aquaporin-4 loss,astrocytopathy,granulocyte and macrophage infiltration,complement activation,demyelination,and neuronal loss;however,they do not fully capture the pathological process of human neuromyelitis optica spectrum *** this review,we summarize the currently known pathogenic mechanisms and the development of associated experimental models in vitro,ex vivo,and in vivo for neuromyelitis optica spectrum disorders,suggest potential pathogenic mechanisms for further investigation,and provide guidance on experimental model *** addition,this review summarizes the latest information on pathologies and therapies for neuromyelitis optica spectrum disorders based on experimental models of aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders,offering further therapeutic targets and a theoretical basis for clinical trials.

关键词： aquaporin-4 experimental model neuromyelitis optica spectrum disorder pathogenesis

Corrosion protection of magnesium alloys anode by cerium-based anodization coating in magnesium-ait battery

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Journal of Rare Earths 2023年第3期41卷 471-476,I0006页

作者： Xiang You Xiaowei Zhang Chuang Yu Yuanliang Chen huiming li Yanqing Hou lin Tian Ni Yang Gang Xie State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming University of Science and TechnologyKunming 650093China National Engineering Research Center for Rare Earth Materials GRINM Group Co.Ltd.Beijing 100088China GRIREM Advanced Materials Co. Ltd.Beijing 100088China State Key Laboratory of Pressure Hydrometallurgical Technology of Associated Nonferrous Metal Resources Kunming 650031China

CeN_(3)O_(9)·6H_(2)O(0.5,1.0,1.5,and 2.0 g/L)was added into an 8.0%NaCl electrolyte solution to investigate this electrolyte for use in a Mg-air *** effects of the amount of CeN_(3)O_(9)-6H_(2)O on the corrosion resistance of an AZ31 Mg alloy anode and battery performance were investigated using microstructure,electrochemical(dynamic potential polarization method and electrochemical impedance spectroscopy),and battery *** re sults show that the addition of CeN_(3)O_(9)·6H_(2)O to the electrolyte leads to the formation of a Ce(OH)_(3)protective film on the surface of the AZ31 Mg alloy that improves the corrosion resistance of the Mg *** increase in the concentration of CeN_(3)O_(9)·6H_(2)O results in a denser Ce(OH)_(3)protective film and decreases corrosion rate of the AZ31 Mg *** the concentration of CeN_(3)O_(9)·6H_(2)O is 1.0 g/L,the corrosion rate of the Mg alloy is the lowest with a corrosion inhibition rate of70.4%.However,the corrosion rate increases due to the dissolution of the Ce(OH)_(3)protective film when the concentration of CeN_(3)O_(9)-6H_(2)O is greater than 1.0 g/*** the Mg alloy in the electrolyte solution containing CeN_(3)O_(9)-6H_(2)O for 50 h leads to the formation of the Ce(HO)_(3)protective film on its surface,which was confirmed by scanning electron microscopy of the AZ31 *** Mg^(2+)charge transfer resistance increases by 69.5Ωfrom the equivalent circuit diagram,which improves the corrosion resistance of the Mg *** discharge performance of CeN_(3)O_(9)·6H_(2)O improves according to a discharge test,and the discharge time increases by 40 min.

关键词： Az31 magnesium alloy anode CeN_(3)O_(9)·6H_(2)O addition Magnesium-air battery Corrosion rate Electrochemical Rare earths

Lateral Hypothalamic Area Glutamatergic Neurons and Their Projections to the Lateral Habenula Modulate the Anesthetic Potency of Isoflurane in Mice

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Neuroscience Bulletin 2021年第7期37卷 934-946页

作者： Shiyi Zhao Rui li huiming li Sa Wang Xinxin Zhang Dan Wang Juan Guo Huihui li Ao li Tingting Tong Haixing Zhong Qianzi Yang Hailong Dong Department of Anesthesiology and Perioperative Medicine Xijing HospitalFourth Military Medical UniversityXi’an 710032China

The lateral hypothalamic area(LHA)plays a pivotal role in regulating consciousness transition,in which orexinergic neurons,GABAergic neurons,and melanin-concentrating hormone neurons are *** neurons have a large population in the LHA,but their anesthesia-related effect has not been ***,we found that genetic ablation of LHA glutamatergic neurons shortened the induction time and prolonged the recovery time of isoflurane anesthesia in *** contrast,chemogenetic activation of LHA glutamatergic neurons increased the time to anesthesia and decreased the time to *** activation of LHA glutamatergic neurons during the maintenance of anesthesia reduced the burst suppression pattern of the electroencephalogram(EEG)and shifted EEG features to an arousal *** of LHA glutamatergic projections to the lateral habenula(LHb)also facilitated the emergence from anesthesia and the transition of anesthesia depth to a lighter ***,LHA glutamatergic neurons and their projections to the LHb regulate anesthetic potency and EEG features.

关键词： Anesthesia Isoflurane Lateral hypothalamic area Lateral habenula Glutamatergic neuron

THE FLOOD REMOTE SENSING MONITORING ACHIEVES SUCCESS IN JIANGXI PROVINCE

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Natural Disaster Reduction in China 1996年第1期 47-48页

作者： li huiming

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Oxidation Behavior of C/C-SiC Gradient Matrix Composites

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Journal of Materials Science & Technology 2001年第5期17卷 543-546页

作者： Jingyi DENG, Wenchuan liU, Haifeng DU, huiming CHENG and Yiyi li Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China

Oxidation behavior of C/C-SiC gradient matrix composites and C/C composites were compared in stationary air. The results show that oxidation threshold of C-SiC materials increases with the amount of SiC particles in the codeposition matrix. Oxidation rate of C/C-SiC gradient matrix composites is significantly lower than that of C/C material. The micro-oxidation process was observed by SEM.

关键词： Oxidation Behavior of C/C-SiC Gradient Matrix Composites SiC SIC