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Surface Degradation of Bulk AlN+Al Nano-composites

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Journal of Materials Science & Technology 1997年第4期13卷 312-314页

作者： Sun, XC Ye, F Song, XP yang, mc Sun, XK State Key Lab. for RSA Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

Bulk AIN + Al nanocomposite materials were synthesized by sintering the compacts of AIN and Al nanoparticles, which were produced by an active plasma-metal reaction method. The surfaces of as-prepared nanocomposite was investigated by X-ray photoelectron spectroscopy (XPS). Results show the surfaces are much degraded and the degradation products are alumina(Al2O3), boehmite(AlOOH), bayerite(AI(OH)(3)) layer. The mechanism of degradation behaviour in moist environment was also discussed.

关键词： Nanostructured materials

Synthesis and Characterization of Mixed Al+AlN Nanoparticles

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Journal of Materials Science & Technology 1997年第4期13卷 309-311页

作者： Sun, XC yang, mc Ye, F Sun, XK Wei, WD Yu, YD Ping, DH CHINESE ACAD SCI INST MET RESATOM IMAGING SOLIDS LABSHENYANG 110015PEOPLES R CHINA

Mixed Al+AlN nanoparticles were synthesized by an active plasma-metal reaction method. Mean particle size of the mixed Al+AlN nanoparticles is about 30-50 nm. Defects were found in some AIN particles. Moreover, the AIN ratio and its particle size in mixed Al+AlN nanoparticles obtained in different atmospheres (N-2+Ar) increase with increasing N-2 particle pressure, and the specific surface areas of the mixed Al+AlN nanoparticles increase with the AIN ratio. The surface degradation of the Al+AlN exposed to air is estimated by the infrared absorption spectra.

关键词： Nanostructured materials

Anomalous quality factor evolution of induced transparency in a virtualized coupled-oscillator system

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 144-151页

作者： Yunhan yang Han Jia Tuo Liu Yuzhen yang Jun yang Key Laboratory of Noise and Vibration Research Institute of AcousticsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190China

The phenomenon of induced transparency,characterized by a high quality(Q)factor,holds significant importance in the fields of high-precision sensing,energy storage and wave *** transparency systems are often constrained by the limited experimentally accessible parameter space and the lack of independent control over intrinsic parameters,thereby hindering advanced research on high-Q *** we propose a virtualized coupled-oscillator system that enables reconfigurable induced transparency in the reflection *** virtually incorporating a pair of coupled oscillators into an individual acoustic meta-atom,we achieve the manipulation of induced transparency in a decoupled,wide-ranging,and elaborate *** the diverse evolutions across the intrinsic parameter space,we show experimentally a counter-intuitive increase in the Q-factor of the transparency window,which is attributed to the enhanced dissipation of the bright ***,a constant group delay at the center frequency is observed accompanying this *** work demonstrates an intriguing platform as well as a novel strategy to engineer high-Q induced transparency phenomenon,and paves the way towards applications in programmable acoustic sensors,filters and slow-wave devices.

关键词： induced transparency acoustic meta-atom high quality-factor scattering programmable intrinsic parameter

Rapid reduction of air pollution and short-term exposure risks in China

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Journal of Environmental Sciences 2025年第3期149卷 126-138页

作者： Hao Fan Chuanfeng Zhao Yikun yang Xingchuan yang State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentBeijing Normal UniversityBeijing 100875China Laboratory for Climate and Ocean-Atmospheric Studies Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking UniversityBeijing 100871China College of Resource Environment and Tourism Capital Normal UniversityBeijing 100048China

With the continuous control of anthropogenic emissions,China’s air quality has improved significantly in recent *** this background,research on how the short-term exposure risks caused by air pollution in China have changed is *** study utilized hourly concentration data from ground observation stations and the official air quality guidelines of the Ministry of Ecology and Environment of China and the World Health Organization as standards to systematically investigate the spatiotemporal characteristics and short-term exposure risks of air pollution in China from 2015 to *** results indicate that various atmospheric pollutants except for ozone showed a decreasing trend ***,both single pollutant air pollution days(SAPDs)and multiple pollutant air pollution days(MAPDs)showed varying degrees of reduction within 15 and 25 days,*** was dominated mainly by excessive PM_(2.5)and PM_(10)pollutants,while MAPD was dominated mainly by excessive pollutant combinations,including PM_(2.5)+PM_(10),CO+PM_(2.5)+PM_(10),and SO_(2)+PM_(2.5)+PM_(10).As the concentration of atmospheric pollutants decreased,the total excess risk(ER)decreased yearly from 2015 to 2022,but there were significant regional ***,the ER is less than 0.25%in southern China,in the range of 0.25%-0.5%in the North China Plain and some cities in the northeast,and higher than 1%in the *** matter is currently the primary pollutant posing short-term exposure risk in China,especially due to the impact of sandstorm *** study indicates that China’s atmospheric cleaning action is significantly beneficial for reducing health risks.

关键词： Air pollution Emission-reduction Total excess risk Particulate matter China

Engineering strategies of biomaterial-assisted exosomes for skin wound repair:Latest advances and challenges

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Chinese Chemical Letters 2025年第1期36卷 99-109页

作者： yang Xu Le Ma yang Wang Chunmeng Shi Institute of Rocket Force Medicine State Key Laboratory of Trauma and Chemical PoisoningThird Military Medical University(Army Medical University)Chongqing 400038China

The treatment of skin wounds,especially chronic wounds,remains a critical clinical challenge and places a heavy burden on patients and healthcare *** recent years,the engineering strategy of using biomaterial-assisted exosomes has emerged as a powerful tool for skin *** to treatments such as debridement and regular dressing changes,the design of biomaterial-assisted exosomes not only maintains the bioactivity of exosomes at the wound site but also provides an appropriate microenvironment for the repair of complex tissues,thereby accelerating wound *** review systematically introduces the general characteristics of exosomes and their functions in skin wound healing,highlights recent advances in classification of natural exosomes and engineering methods which enriching their functions in intercellular ***,various emerging and innovative approaches based on biomaterials delivery of exosomes are comprehensively *** review seeks to bring an in-depth understanding of bioactive dressings based on exosomes therapeutic strategies,aiming to facilitate new clinical application value.

关键词： Exosomes Biomaterials Hydrogel Delivery system Wound healing

Hyperosmolality tolerance of freshwater largemouth bass Micropterus salmoides to brackish in early ontogenetic stages of eggs,embryos,and yolk-sac larvae

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Journal of Oceanology and Limnology 2025年第1期43卷 286-298页

作者： Du LUO Dingtian yang South China Sea Institute of Oceanology Chinese Academy of SciencesGuangzhou 510301China Pearl River Fisheries Research Institute Chinese Academy of Fishery SciencesGuangzhou 510380China University of Chinese Academy of Sciences Beijing 100049China

Salinity is recognized as a pivotal factor limiting the migration of freshwater fish to brackish *** largemouth bass(LMB,Micropterus salmoides),a globally translocated freshwater fish,exhibits estuarine distribution,yet its hyperosmoregulatory capacity during early ontogenetic stages remains inadequately *** investigate the impact of freshwater salinization,a series of experiments were conducted in Guangzhou and Foshan,*** reveal that freshwater-activated mature eggs and naturally fertilized oocytes maintained nearly identical osmotic homeostasis,with diameters of 1.38±0.07 mm and 1.37±0.05 mm,***,both exhibited peak water excretion at a salinity of ***,a reduction in water permeability was observed in hyperosmotic *** hatching rates increased from 27.5%±14.4%in the 1.0 group to 75.1%±12.0%in the 6.0 group under fluctuating temperature ***-sac LMB larvae consistently reduced survival time from 12.5 d at 1.0 to 50.7±2.1 min at salinity of ***,more developed larvae also experienced a decrease in survival *** regression models fitting lethal time with salinity indicated a sharp decrease between 10.0 and *** findings offer practical insights for predicting distribution patterns and enhancing aquaculture technology for ***,they may contribute theoretically to the broader understanding of the osmoregulatory mechanisms of freshwater fish.

关键词： osmotic homeostasis acute toxicity median lethal time hatching rate dose-response model

Multiphysics simulation and optimization of the in-situ beneficiation process of ilmenite minerals from lunar regolith

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Science China Earth Sciences 2025年第1期68卷 195-207页

作者： Peng ZHANG Xin LIU Guanghui LIU Wei DAI Hanzhe yang Haibo ZHENG Zhi WANG Ran NIU Yifan BAI yang ZHANG Chengbao LIU Ge yang Junwei yang Guang ZHANG Technology and Engineering Center for Space Utilization Chinese Academy of SciencesBeijing100094China Beijing Hegong Simulation Co. LtdBeijing100089China

The exploration and utilization of lunar resources have become the major objectives of future lunar exploration *** classified collection and processing of lunar minerals is the basic prerequisite for the in-situ exploration and utilization of lunar *** this study,we propose a scheme for in-situ separation of magnetic minerals from lunar soils using the dry magnetic separation *** scheme can realize the purpose of separating magnetic minerals from lunar regolith by altering the motion trajectory of lunar regolith particles with different magnetic *** modeling of the dry magnetic separation device is conducted,and the three-dimensional distribution of magnetic parameters is calculated and *** on the characterization and analysis of the Chang E-5's samples,the morphologies and physical parameters of lunar regolith particles are modeled and simulated.A discrete element simulation of the motion process of lunar regolith particles under multi-physical field conditions is performed,and the influences of key parameters on the beneficiation performance of lunar magnetic minerals are *** results indicate that optimal separation and beneficiation of lunar regolith particles can be achieved under specific conditions of magnetic field strength and drum ***,we analyze the effects of lunar weak gravity conditions and the charged nature of lunar particles on the beneficiation process,showing that these factors can obviously enhance the beneficiation process of lunar *** study demonstrates the feasibility of using the dry magnetic separation method for the beneficiation of magnetic minerals from lunar regolith,providing a theoretical basis for the scientific tasks of collecting,processing,and utilizing lunar mineral resources.

关键词： Lunar regolith In-situ resource utilization Magnetic separation Classified sampling

Graph reinforcement learning with relational priors for predictive power allocation

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Science China(Information Sciences) 2025年第2期68卷 230-247页

作者： Jianyu ZHAO Chenyang yang School of Electronics and Information Engineering Beihang University

Deep reinforcement learning for resource allocation has been investigated extensively owing to its ability of handling model-free and end-to-end problems. However, its slow convergence and high time complexity during online training hinder its practical use in dynamic wireless systems. To reduce the training complexity, we resort to graph reinforcement learning for leveraging two kinds of relational priors inherent in many wireless communication problems: topology information and permutation properties. To harness the two priors, we first conceive a method to convert the state matrix into a state graph,and then propose a graph deep deterministic policy gradient(DDPG) algorithm with the desired permutation property. To demonstrate how to apply the proposed methods, we consider a representative problem of using reinforcement learning, predictive power allocation, which minimizes the energy consumption while ensuring the quality-of-service of each user requesting video streaming. We derive the time complexity required by training the proposed graph DDPG algorithm and fully-connected neural network-based DDPG algorithm in each time step. Simulations show that the graph DDPG algorithm converges much faster and needs much lower time and space complexity than existing DDPG algorithms to achieve the same learning performance.

关键词： reinforcement learning graph neural network relational priors resource allocation

Selenate-based heterojunction with cobalt-nickel paired site for electrocatalytic oxidation of 5-hydroxymethylfurfural coupling water splitting to produce hydrogen

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Journal of Energy Chemistry 2025年第2期101卷 156-162页

作者： Zhengru yang Jia Hui Wangxi Fan Pengcheng Liu Chunyong Zhang Shuang Dong Zhou yang Department of Chemistry and Chemical Engineering & Jiangsu Key Laboratory of Clean Energy Storage and Conversion Jiangsu University of Technology Engineering Technology and Materials Research Center China Academy of Transportation Sciences School of Chemical Engineering and Materials Changzhou Institute of Technology

It is very appealing that 5-hydroxymethylfurfural（HMF） is electrocatalytical oxidized as 2,5-furandicarboxylic acid（FDCA） linking to non-classical cathodic hydrogen（H2） ***,the electrocatalysts for electrocatalytic HMF oxidative reaction（e-HMFOR） have been facing low Faradaic efficiency（FE） and high water splitting ***,we propose a strategy of the NiSeO3@（CoSeO3）4heterojunction by constructing a Co-Ni paired site,where the Co site is in charge of adsorbing for HMF while the electrons are transferred to the Ni site,thus giving the NiSeO3@（CoSeO3）4heterojunction superior electrocata lytic performances for e-HMFOR and water *** optimizing conditions,the NiSeO3@（CoSeO3）4heterojunction has high conversion of 99.7%,high selectivity of 99.9%,and high FE of 98.4% at 1.3 V,as well as low cell voltage of 1.31 V at 10 mA cm-2in 1 M KOH+0.1 M *** study offers a potential insight for e-HMFOR to high value-added FDCA coupling water splitting to produce H2in an economical manner.

关键词： Co-Ni paired site e-HMFOR FDCA Heterojunction Hydrogen evolution