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Rare Metals 2024年第2期43卷 588-598页

作者： Fei Wang Han Gao zhao-yu niu Yao-Peng Zheng Ming-Yan Chuai Jia-Nan Xu State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China University of Science and Technology of China Hefei230026China

In the current situation where the practical application of silicon anode materials encounters great challenges,silicon oxide(SiO_(x),0≤x≤2)has attracted the attention of researchers due to its relatively small volume expansion,stable cycling performance,and low cost,which is possible to realize commercial applications earlier than silicon ***,it remains a challenge to prepare SiO_(x)materials with long-term stable cycling performance and high Coulombic efficiency using low-cost *** this work,SiO_(x)anode material with high Coulombic efficiency and good long-term cycling stability was prepared at a low cost by hydrolysis of siloxane and in situ polymerization of phenolic *** hydrolysis of siloxane was further regulated by different silane coupling agents to regulate the size and microstructure of prepared SiO_(x)materials,which displayed the substantially improved electrochemical *** excellent electrochemical performance of SiO_(x)prepared by regulated hydrolysis of siloxane with silane coupling agents is attributed to the effect of silane coupling agent on size and microstructure of SiO_(x),revealing that the strategy of modulating the hydrolysis of siloxane by silane coupling agent is a potential method to prepare high-performance SiO_(x)materials.

关键词： Hydrolysis Silane coupling agent Long cycle SiO_(x) anode Lithium-ion battery(LIB)

Development of wet adhesion of honeybee arolium incorporated polygonal structure with three-phase composite interfaces

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Friction 2024年第2期12卷 215-230页

作者： Lulu LIANG Jieliang zhao Qun niu Li yu Xiangbing WU Wenzhong WANG Shaoze YAN Zhenglei yu School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Division of Intelligent and Biomechanical Systems State Key Laboratory of TribologyDepartment of Mechanical EngineeringTsinghua UniversityBeijing 100084China Key of Bionic Engineering Ministry of EducationJilin UniversityChangchun 130022China

Inspired by the dynamic wet adhesive systems in nature,various artificial adhesive surfaces have been developed but still face different ***,the theoretical mechanics of wet adhesives has never been sufficiently ***,we develop a novel adhesive mechanism for governing wet adhesion and investigate the biological models of honeybee arolium for reproducing the natural wet adhesive ***-nano structures of honeybee arolium and arolium-prints were observed by Cryogenic scanning electron microscopy(Cryo-SEM),and the air pockets were found in the contact interface ***,the adhesive models with a three-phase composite interface(including air pockets,liquid secretion,and hexagonal frames of arolium),were formed to analyze the wet adhesion of honeybee *** results of theoretical calculations and experiments indicated an enhanced adhesive mechanism of the honeybee by liquid self-sucking effects and air-embolism *** these effects,normal and shear adhesion can be adjusted by controlling the proportion of liquid secretion and air pockets in the contact ***,the air-embolism effects contribute to the optimal coupling of smaller normal adhesion with greater shear adhesion,which is beneficial for the high stride frequency of *** works can provide a fresh perspective on the development of bio-inspired wet adhesive surfaces.

关键词： honeybee arolium air pockets wet adhesion a three-phase interface self-sucking effects air-embolism effects

An integrative mathematical model of microwave ion thruster for mHz-frequency thrust noise analysis

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Chinese Journal of Aeronautics 2024年第4期37卷 121-136页

作者： Xiang niu Hui LIU Daren yu Plasma Propulsion Laboratory Harbin Institute of TechnologyHarbin 150001China

Many high-precision space missions need thrusters to produce thrust with low noise to compensate for disturbances and ensure satellite platform stability. Microwave ion thruster is characterized with a wide thrust range and potential for these missions. A cost-effective and accurate mathematical model is crucial for mHz-frequency thrust noise analysis and feedback controller design. The Particle-In-Cell(PIC) and global models are two common simulation tools. The PIC model is characterized with high accuracy but huge computation cost, which is difficult to analyze long-time performance characteristics. Now, the global model is only used for the discharge chamber with low accuracy and cannot reflect ion extraction properties. In this paper, an integrative mathematical model is built for a 1-cm microwave ion thruster and can reflect ion beamlet divergence and impingement on the Accelerator Grid(AG). Simulation results show good agreement with experiments at 0.06 sccm. However, the model demonstrates worse consistency with experiments when the flux increases to 0.1 sccm, which may be because the influence of neutral gas on the Electron Cyclotron Resonance(ECR) is not considered in the model. A long-time(1000 s) simulation is conducted with this model under 35 μN. It takes 3 hrs, and the thrust noise reaches 1 μN/Hz^(0.5) at 1 mHz.

关键词： Electric propulsion Microwave ion thruster Integrative model Sheath property Ion beamlet divergence Thrust noise Plasma

Machine Learning-Based Research on Tensile Strength of SiC-Reinforced Magnesium Matrix Composites via Stir Casting

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 453-466页

作者： Zhihong Zhu Wenhang Ning Xuanyang niu yuhong zhao Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering Collaborative Innovation Center of Ministry of Education and Shanxi Province for High-Performance Al/Mg Alloy MaterialsNorth University of ChinaTaiyuan 030051China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China

SiC is the most common reinforcement in magnesium matrix composites,and the tensile strength of SiC-reinforced magnesium matrix composites is closely related to the distribution of *** a uniform distribution of SiC requires fine control over the parameters of SiC and the processing and preparation ***,due to the numerous adjustable parameters,using traditional experimental methods requires a considerable amount of experimentation to obtain a uniformly distributed composite ***,this study adopts a machine learning approach to explore the tensile strength of SiC-reinforced magnesium matrix composites in the mechanical stirring casting *** analyzing the influence of SiC parameters and processing parameters on composite material performance,we have established an effective predictive ***,six different machine learning regression models have been developed to predict the tensile strength of SiC-reinforced magnesium matrix *** validation and comparison,our models demonstrate good accuracy and reliability in predicting the tensile strength of the composite *** research findings indicate that hot extrusion treatment,SiC content,and stirring time have a significant impact on the tensile strength.

关键词： Machine learning Stirring casting Magnesium matrix composite Tensile strength

Application of horticulture therapy as a health intervention for elderly people in nursing homes:a scoping review

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Frontiers of Nursing 2024年第3期11卷 231-242页

作者： Jing-Jing Wang Xiao-yu niu Ming-Li zhao Department of Community Health Nursing School of Nursing and HealthZhengzhou UniversityZhengzhouHenan 450007China Department of Nursing Shanghai Fifth People’s HospitalFudan UniversityShanghai 200240China

Objective:To review the scope of interventional studies on horticultural therapy(HT)applied to elderly people in nursing institutions to support the efficient implementation of HT among this target ***:In accordance with the scoping review framework proposed by the Joanna Briggs Institute(JBI),the Pub Med,JSTOR,Web of Science,CNKI,and Wanfang databases were *** from the retrieved literature were summarized and ***:In all,18 studies were included in this *** target population groups of interventions included self-supporting elderly people,cognitively impaired elderly people,elderly people with negative emotions,and elderly people with frailty living in nursing *** interventions,including planting,craft activities,derivative activities,and outdoor viewing activities,are implemented indoors,outdoors,or in mixed *** most common duration of the intervention was 8 weeks,the most common frequency was once per week,and the most common session duration was 60 ***:The measurements used in HT interventions included assessments of physical,psycho-mental,and social health;quality of life;and activity *** studies should include partially dependent groups and completely dependent groups of elderly individuals,interventions that last at least 6 months,scientifically designed activity intensity and safety-guarantee plans,and outcomeevaluation indicators such as compliance and intervention benefits.

关键词： elderly people horticultural therapy intervention nursing home scoping review

The Multi-parameter Test of Gravitational Wave Dispersion with Principal Component Analysis

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Research in Astronomy and Astrophysics 2024年第5期24卷 140-150页

作者： Zhi-Chu Ma Rui niu Wen zhao CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China

In this work, we consider a conventional test of gravitational wave(GW) propagation which is based on the phenomenological parameterized dispersion relation to describe potential departures from General Relativity(GR)along the propagation of GWs. But different from tests conventionally performed previously, we vary multiple deformation coefficients simultaneously and employ the principal component analysis(PCA) method to remedy the strong degeneracy among deformation coefficients and obtain informative posteriors. The dominant PCA components can be better measured and constrained, and thus are expected to be more sensitive to potential departures from the waveform model. Using this method we analyze ten selected events and get the result that the combined posteriors of the dominant PCA parameters are consistent with GR within 99.7% credible intervals. The standard deviation of the first dominant PCA parameter is three times smaller than that of the original dispersion parameter of the leading order. However, the multi-parameter test with PCA is more sensitive to not only potential deviations from GR but also systematic errors of waveform models. The difference in results obtained by using different waveform templates hints that the demands of waveform accuracy are higher to perform the multiparameter test with PCA. Whereas, it cannot be strictly proven that the deviation is indeed and only induced by systematic errors. It requires more thorough research in the future to exclude other possible reasons in parameter estimation and data processing.

关键词： gravitational waves-gravitation-black hole physics

Observation and Analysis of VLF Nocturnal Multimode Interference Phenomenon based on Waveguide Mode Theory

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Research in Astronomy and Astrophysics 2024年第1期24卷 78-86页

作者： Sai Yang You-Tian niu Zhe Wang Xiu-Kun zhao Bei Li yu-Ling Ding Ge-Ge zhao An-Qi Zhang College of Electronic and Electrical Engineering Henan Normal UniversityXinxiang 453007China Academician Workstation of Electromagnetic Wave Engineering of Henan Province Xinxiang 453007China Key Laboratory of Optoelectronic Sensing Integrated Application of Henan Province Xinxiang 453007China Engineering Laboratory of Intelligent Additive Manufacturing of Henan Province Xinxiang 453007China

Very low frequency(VLF)signals are propagated between the *** interference will cause the phase to show oscillatory changes with distance while propagating at night,leading to abnormalities in the received VLF *** study uses the VLF signal received in Qingdao City,Shandong Province,from the Russian Alpha navigation system to explore the multimode interference problem of VLF signal *** characteristics of the effect of multimode interference phenomena on the phase are analyzed according to the variation of the phase of the VLF ***,the phase of VLF signals will also be affected by the X-ray and energetic particles that are released during the eruption of solar flares,therefore the two phenomena are studied in this *** is concluded that the X-ray will not affect the phase of VLF signals at night,but the energetic particles will affect the phase change,and the influence of energetic particles should be excluded in the study of multimode interference *** VLF signals for navigation positioning in degraded or unavailable GPS conditions is of great practical significance for VLF navigation systems as it can avoid the influence of multimode interference and improve positioning accuracy.

关键词： waves methods:data analysis Sun:flares Sun:X-rays gamma-rays

UKF‐MOT:An unscented Kalman filter‐based 3D multi‐object tracker

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CAAI Transactions on Intelligence Technology 2024年第4期9卷 1031-1041页

作者： Meng Liu Jianwei niu yu Liu Collective Intelligence&Collaboration Laboratory China North Artificial Intelligence and Innovation Research InstituteBeijingChina China North Vehicle Research Institute BeijingChina State Key Laboratory of Software Development Environment School of Computer Science and EngineeringBeihang UniversityBeijingChina State Key Laboratory of Virtual Reality Technology and Systems School of Computer Science and EngineeringBeihang UniversityBeijingChina School of Computer Science and Engineering Beihang UniversityBeijingChina

Multi‐object tracking in autonomous driving is a non‐linear *** better address the tracking problem,this paper leveraged an unscented Kalman filter to predict the object's *** the association stage,the Mahalanobis distance was employed as an affinity metric,and a Non‐minimum Suppression method was designed for *** the detections fed into the tracker and continuous‘predicting‐matching’steps,the states of each object at different time steps were described as their own continuous *** conducted extensive experiments to evaluate tracking accuracy on three challenging datasets(KITTI,nuScenes and Waymo).The experimental results demon-strated that our method effectively achieved multi‐object tracking with satisfactory ac-curacy and real‐time efficiency.

关键词： autonomous vehicle transportation

A study on carbon emission calculation in operation stage of residential buildings based on micro electricity usage behavior:Three case studies in China

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Building Simulation 2024年第1期17卷 147-164页

作者： Menghan niu Ying Ji Miao zhao Jiefan Gu Aonan Li Beijing Key Laboratory of Green Built Environment and Energy Efficient Technology Beijing University of TechnologyBeijing 100124China College of Architecture and Urban Planning Tongji UniversityShanghai 201804China The Bartlett School of Architecture University College LondonWC1E 6BTUK

Along with the improvement of social productivity and living standard,residential buildings generate a growing portion of carbon emissions,especially during the operation ***,energy use behaviors are usually ignored in carbon emission *** study focuses on calculating carbon emissions during the operation stage for residential buildings based on the characteristics of energy use behaviors in different ***,we investigated energy use behaviors in dwellings across three cities in China:Xi'an,Shanghai and ***,we established calibrated carbon emission models and optimization models with different green building measures for residential *** results of this research reveal a significant disparity between the energy usage habits of residents in different climate *** carbon emissions of residential electricity bills in Xi'an,Shanghai and Fuzhou are 13.6 kgCO_(2)/(m^(2)·a)(excluding central heating),29.3 kgCO_(2)/(m^(2)·a)and 17.2 kgCO_(2)/(m^(2)·a),*** carbon emissions account for 32.2%-64.1% of the *** comparison to the model based on internal standard setting,the accuracy of the models using actual internal has improved by 25.9%-37.4%.The three-star green building methods have the highest carbon reduction rate among different star buildings,the emission reduction rates are around 30%.This study's findings are useful for carbon emission calculation and green building design of residential buildings in the future.

关键词： residential building energy usage behavior energy simulation carbon emissions

Living Chinese Herbal Scaffolds from Microfluidic Bioprinting for Wound Healing

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Research 2024年第1期2023卷 107-118页

作者： Xiaocheng Wang Jinxuan Jia Mengying niu Wenzhao Li yuanjin zhao Department of Rheumatology and Immunology Nanjing Drum Tower HospitalSchool of Biological Science and Medical EngineeringSoutheast UniversityNanjing 210096China Oujiang Laboratory(Zhejiang Lab for Regenerative Medicine Vision and Brain Health)Wenzhou InstituteUniversity of Chinese Academy of SciencesWenzhouZhejiang 325001China State Key Laboratory of Bioelectronics School of Biological Science and Medical EngineeringSoutheast UniversityNanjing 210096China Chemistry and Biomedicine Innovation Center Nanjing UniversityNanjing 210023China

Biological scaffolds have been widely employed in wound healing applications,while their practical efficiency is compromised by insufficient oxygen delivery to the 3-dimensional constructs and inadequate nutrient supply for the long-term healing ***,we present an innovative living Chinese herbal scaffold to provide a sustainable oxygen and nutrient supply for promoting wound *** a facile microfluidic bioprinting strategy,a traditional Chinese herbal medicine(Panax notoginseng saponins[PNS])and a living autotrophic microorganism(microalgae Chlorella pyrenoidosa[MA])were successfully encapsulated into the *** encapsulated PNS could be gradually released from the scaffolds,which promoted cell adhesion,proliferation,migration,and tube formation in *** addition,benefiting from the photosynthetic oxygenation of the alive MA,the obtained scaffolds would produce sustainable oxygen under light illumination,exerting a protective effect against hypoxia-induced cell *** on these features,we have demonstrated through in vivo experiments that these living Chinese herbal scaffolds could efficiently alleviate local hypoxia,enhance angiogenesis,and thereby accelerate wound closure in diabetic mice,indicating their great potential in wound healing and other tissue repair applications.

关键词： healing wound protective