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Rich defects and nanograins boosted formaldehyde sensing performance of mesoporous polycrystalline ZnO nanosheets

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Rare Metals 2022年第7期41卷 2292-2304页

作者： Le-Xi Zhang Ming-Mei zhao Yan-Yan Yin Yue xing Li-jian Bie School of Materials Science and Engineering Tianjin Key Laboratory for Photoelectric Materials and DevicesKey Laboratory of Display Materials and Photoelectric Devices(Ministry of Education)National Demonstration Center for Experimental Function Materials EducationTianjin University of TechnologyTianjin 300384China Department of Environmental Science and Engineering Nankai University Binhai CollegeTianjin 300270China

Comprehensive consideration of structural and electronic sensitization is of significant importance for rational design and assembly of high-performance gas sensors based on metal *** this work,hierarchically mesoporous ZnO nanosheets are synthesized via a hydrothermal method followed by *** characterization reveals polycrystalline feature of these ZnO nanosheets rich in mesopores and *** sensing performance of as-synthesized ZnO nanosheets was sys-tematically investigated,taking formaldehyde as probe *** with commercial ZnO nanoparticles,ZnO nanosheets exhibited enhanced formaldehyde sensing properties,including lower operation temperature,higher sensitivity,faster response,and smaller detection ***,the response(S=227.4)of ZnO nanosheets to 200×10^(-6) formaldehyde is about 17 times larger than that of ZnO nanoparticles(S=13.5).Excluding effects of grain size and surface area,enhanced sensing properties,especially response value,are credited in large part to synergistic actions of surface defects,grain boundaries,as well as unique structural advantage of ZnO ***,this work offers a guideline for boosting performance of metal oxide-based gas sensors via surface defect control and grain boundary construction.

关键词： performance polycrystalline grain

Application of preblasting to high-section top coal caving for steepthick coal sea

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Journal of Coal Science & Engineering(China) 2011年第2期17卷 113-118页

作者： zhao jian-hui LAI xing-ping School of Energy Engineering Xi＇an University of Science and Technology Xi＇an 710054 China Key Laboratory of Western Mines and Hazard Prevention Ministry of Education of China Xi＇an 710054 China

For mining extra-steep-thick coal seam, the sublevel top coal caving is a high efficient method in practical engineering. However, major challenges associated with mining high-section top-coal-caving （HSTCC） are related to the resulting high ground stresses. Inevitability, using the high-section sublevel top coal caving for extra-steep-thick coal seam, the large scale of mined-out area appears. If the prefracture blasting and hydraulic fracture techniques are utilized, the top coal damage and cracks will develop, and the mining complexity will increase, such as seam inclination, continuity, mechanical characteristics of roof and susceptibility of top coal, etc. First, the field conditions of B1＋2 seam were investigated at the ＋588 level of the Weihuliang Underground Mine of China. Subsequently, according to caving mechanism of strata response obtained from several special models including physical simulation tests and numerical simulation models, the prefracture process including blasting and injecting water were analyzed. Then, the prefracture blasting technique was successfully applied to the caving of 52 m-sublevel seam. Finally, the effects were verified by advanced detecting instruments, and the results show these methods and measurements are feasible and valid.

关键词： extra-steep-thick seam high-section top-coal caving (HSTCC) prefracture blasting and verification

Molecular simulation study of the microstructures and properties of pyridinium ionic liquid[HPy][BF_(4)]mixed with acetonitrile

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原子与分子物理学报 2025年第4期42卷 27-32页

作者： XU jian-Qiang MA zhao-Peng CHENG Si LIU Zhi-Cong ZHU Guang-Lai Department of Physics School of Physics and Electronic InformationAnhui Normal UniversityWuhu 241002China

The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this *** following properties were determined:density,self-diffusion coefficient,excess molar volume,and radial distribution *** results show that with an increase in the mole fraction of[HPy][BF_(4)],the self-diffusion coefficient ***,the excess molar volume initially decreases,reaches a minimum,and then *** rules of radial distribution functions(RDFs)of characteristic atoms are *** increasing the mole fraction of[HPy][BF_(4)],the first peak of the RDFs of HA1-F decreases,while that of CT6-CT6 rises at first and then *** indicates that the solvent molecules affect the polar and non-polar regions of[HPy][BF_(4)]differently.

关键词： Pyridinium ionic liquids Thermodynamic properties Molecular dynamics simulation Radial distribution functions

Mechanisms of secondary damage to the thalamic nucleus and substantia nigra in an adult hypertensive rat model following middle cerebral artery occlusion

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Neural Regeneration Research 2010年第11期5卷 853-858页

作者： Li Xiong jian Yu Songjie Liao Shihui xing Zhan zhao Jinsheng Zeng Stroke Center and Department of Neurology First Affiliated Hospital Sun Yat-Sen University Guangzhou 510080 Guangdong ProvinceChina

BACKGROUND： Following ischemia, apoptosis is observed at the ipsilateral ventropostenor thalamic nucleus and substantia nigra, which are distant from, but connected to, the ischemic cerebral cortex, in animals with normotension. However, secondary brain damage in hypertension has not been clearly investigated. OBJECTIVE： The present study determined whether neuronal apoptosis is associated with neuronal loss in the ipsilateral ventroposterior thalamic nucleus and substantia nigra following cortical ischemia in adult hypertensive rats. Results should provide options for determining a time window for anti-apoptotic therapy. DESIGN, TIME AND SETTING： All experimental procedures in this randomized, controlled trial were conducted at the Neurological Laboratory of the First Affiliated Hospital of Sun Yat-sen University of China between October 2006 and July 2008. MATERIALS： Monoclonal primary antibodies specific to mouse anti-rat microtubule-associated protein 2 and glial fibrillary acidic protein were respectively purchased from Sigma Chemical, USA and BD Pharmingen, USA. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling （TUNEL） detection kits were purchased from Roche Applied Science, Switzerland and Upstate, USA, respectively. METHODS： A total of 64 male, Sprague Dawiey rats, aged 60-90 days, were equally and randomly divided into middle cerebral artery occlusion and sham surgery groups. Renovascular hypertension was established in both groups by renal artery occlusion. Right distal middle cerebral artery occlusion was performed by electrocoagulation in the middle cerebral artery occlusion group. MAIN OUTCOME MEASURES： Microtubule-associated protein 2 and glial fibrillary acidic protein were detected by immunohistochemistry, and apoptotic cells were observed by TUNEL assay. The stainings were separately detected in the ipsilateral ventroposterior thalamic nucleus and substantia nigra. RESULTS： During the 4 weeks followin

关键词： ventroposterior thalamic nucleus substantia nigra apoptosis rats cerebral infarction neural regeneration

Mutations of N-Methyl-D-Aspartate Receptor Subunits in Epilepsy

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Neuroscience Bulletin 2018年第3期34卷 549-565页

作者： xing-xing Xu jian-Hong Luo Department of Neurobiology Key Laboratory of Medical Neurobiology(Ministry of Health of China) Collaborative Innovation Center for Brain Science Zhejiang University School of Medicine

Epilepsy is one of the most common neurological diseases. Of all cases, 70%–80% are considered to be due to genetic factors. In recent years, a large number of genes have been identified as being involved in *** them, N-methyl-D-aspartate receptor（NMDAR）subunit-encoding genes represent a large proportion, suggesting an important role for NMDARs in epilepsy. In this review, we summarize and analyze the genotypes, functional alterations, and clinical aspects of NMDAR subunit mutations/variants identified from patients with *** data will help to throw light upon the pathogenicity of these NMDAR mutations and advance our understanding of the subtle and complicated role of NMDARs in epilepsy. It will also offer new insights into precision therapy for this disorder.

关键词： Epilepsy NMDA receptors Subunit Mutation

Synthesis and Crystal Structure of a New Mononuclear Cobalt(Ⅲ) Complex with 2,2′-Dipyridylamine and Glycine as Ligands

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Chinese Journal of Structural Chemistry 2007年第2期26卷 189-193页

作者： CHEN Jun XU xing-You GAO jian MA Wei-xing LI Yan-Hui LI Shan-Zhong zhao Hong Department of Chemtcal Engmeering HuaihaiInstitute of Technology Lianyungang Jiangsu 222005 China Coordination Chemistry Institution State Key Laboratory ofCoordination Chemistry Nanjing University Nanjing 210093 China Materials Chemistry Laboratory Nanjing Universityof Science ＆ Technology Nanjing 210094 China

A new mononuclear cobalt（Ⅲ） complex [Co（dpa）2（Gly）]（ClO4）2-4H2O was synthesized by the reaction of Co^2＋, glycine （gly） and 2,2＂-dipyridylamine （dpa） in a methanol-water solution, and its structure was characterized by IR, EA, ES-MS and X-ray structure analysis. The compound crystallizes in the monoclinic system, space group P21/n with a = 12.8795（2）, b = 13.2904（2）, c = 19.1104（2）A, β= 109.378（1）°, V = 3085.89（8）A^3, Z = 4, Mr = 746.36, Dc = 1.606 g/cm^3, μ= 0.808 mm^-1, F（000） = 1536, the final R = 0.0543 and wR = 0.1306 for 5393 independent reflections. The magnetic measurement of the compound at room temperature shows that it is diamagnetic and the cobalt ion is in low spin ＋3 oxidation state. ES-MS experiments show that the [Co（dpa）E（Gly）]^2＋ cation is very stable in the methanol solution.

关键词： cobalt complex mononuclear crystal structure

Two-dimensional piston pump: Principle, design,and testing for aviation fuel pumps

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Chinese Journal of Aeronautics 2020年第4期33卷 1349-1360页

作者： Tong xing Yezhou XU jian RUAN Key Laboratory of Special Purpose Equipment and Advanced Manufacturing Technology Ministry of Education Zhejiang University of TechnologyHangzhou 310018China The State Key Laboratory of Fluid Power and Mechatronic Systems Hangzhou 310027China

Aviation fuel pumps of the future are required to be highly efficient and *** such,this work presents the designs of various mechanisms and structures of advanced twodimensional piston pumps for aero-engines,and their universal kinematic design methods are detailed *** efficiency of various piston pump prototypes was experimentally tested at various speeds in an open *** experimental results indicate that two-dimensional piston pumps have a volumetric efficiency>91%and a higher power–mass ratio than conventional fuel pumps under all the conditions ***,the structural and material problems encountered during testing can provide a blueprint for further improvement of the design and processing of two-dimensional piston fuel pumps.

关键词： Fuel pumps Kinematics–design Mechanical design Structure design Two-dimensional piston pumps

Dynamic plugging regulating strategy of pipeline robot based on reinforcement learning

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Petroleum Science 2024年第1期21卷 597-608页

作者： xing-Yuan Miao Hong zhao College of Mechanical and Transportation Engineering China University of PetroleumBeijing102249China

Pipeline isolation plugging robot (PIPR) is an important tool in pipeline maintenance operation. During the plugging process, the violent vibration will occur by the flow field, which can cause serious damage to the pipeline and PIPR. In this paper, we propose a dynamic regulating strategy to reduce the plugging-induced vibration by regulating the spoiler angle and plugging velocity. Firstly, the dynamic plugging simulation and experiment are performed to study the flow field changes during dynamic plugging. And the pressure difference is proposed to evaluate the degree of flow field vibration. Secondly, the mathematical models of pressure difference with plugging states and spoiler angles are established based on the extreme learning machine (ELM) optimized by improved sparrow search algorithm (ISSA). Finally, a modified Q-learning algorithm based on simulated annealing is applied to determine the optimal strategy for the spoiler angle and plugging velocity in real time. The results show that the proposed method can reduce the plugging-induced vibration by 19.9% and 32.7% on average, compared with single-regulating methods. This study can effectively ensure the stability of the plugging process.

关键词： Pipeline isolation plugging robot Plugging-induced vibration Dynamic regulating strategy Extreme learning machine Improved sparrow search algorithm Modified Q-learning algorithm

Parametric Geometric Model and Hydrodynamic Shape Optimization of A Flying-Wing Structure Underwater Glider

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China Ocean Engineering 2017年第6期31卷 709-715页

作者： WANG Zhen-yu YU jian-cheng ZHANG Ai-qun WANG Ya-xing zhao Wen-tao State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China University of Chinese Academy of Sciences Beijing 100049 China

Combining high precision numerical analysis methods with optimization algorithms to make a systematic exploration of a design space has become an important topic in the modern design methods. During the design process of an underwater glider＇s flying-wing structure, a surrogate model is introduced to decrease the computation time for a high precision analysis. By these means, the contradiction between precision and efficiency is solved effectively. Based on the parametric geometry modeling, mesh generation and computational fluid dynamics analysis, a surrogate model is constructed by adopting the design of experiment （DOE） theory to solve the multi-objects design optimization problem of the underwater glider. The procedure of a surrogate model construction is presented, and the Gaussian kernel function is specifically discussed. The Particle Swarm Optimization （PSO） algorithm is applied to hydrodynamic design optimization. The hydrodynamic performance of the optimized flying-wing structure underwater glider increases by 9.1%.

关键词： surrogate model underwater glider design optimization blended-wing-body