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Characteristics of atomic layer deposited transparent aluminumdoped zinc oxide thin films at low temperature

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Rare Metals 2016年第7期35卷 509-512页

作者： Fei-Long Zhao Jun-Chen Dong Nan-Nan Zhao jing Wu De-Dong Han jin-feng kang Yi Wang Shenzhen Graduate School Peking University Institute of Microelectronics Peking University

Various aluminum-doped zinc oxide （AZO） films were prepared on Si substrate by atomic layer de- position （ALD） at 100 ℃. The effect of the composition of AZO films on their electrical, optical characteristics, structural property and surface topography was investi- gated. The appearance of electrical resistivity shows their semiconducing properties. In most of the visible light band, all the AZO films present transparency of more than 80 %. A1 doping suppresses the AZO film crystallization. When the A1 doping concentration increases up to 3.95 at%, the AZO film has some small multicrystal grains with random orientation. A1 doping improves the roughness of i-ZnO film. The root mean square （RMS） roughness of samples prepared by ALD is much smaller than that pre- pared by radio-frequency magnetron sputtering reported.

关键词： Atomic layer deposition Aluminum-doped ZnO thin film Transparent Uniformity

Failure rate analysis and maintenance plan optimization method for civil aircraft parts based on data fusion

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Chinese Journal of Aeronautics 2025年第1期38卷 306-324页

作者： kang CAO Yongjie ZHANG Jianfei feng School of Civil Aviation Northwestern Polytechnical UniversityXi’an 710072China Shanghai Aircraft Design and Research Institute Shanghai 201210China

In the face of data scarcity in the optimization of maintenance strategies for civil aircraft,traditional failure data-driven methods are encountering challenges owing to the increasing reliability of aircraft *** study addresses this issue by presenting a novel combined data fusion algorithm,which serves to enhance the accuracy and reliability of failure rate analysis for a specific aircraft model by integrating historical failure data from similar models as supplementary *** a comprehensive analysis of two different maintenance projects,this study illustrates the application process of the *** upon the analysis results,this paper introduces the innovative equal integral value method as a replacement for the conventional equal interval method in the context of maintenance schedule *** Monte Carlo simulation example validates that the equivalent essential value method surpasses the traditional method by over 20%in terms of inspection efficiency *** discovery indicates that the equal critical value method not only upholds maintenance efficiency but also substantially decreases workload and maintenance *** findings of this study open up novel perspectives for airlines grappling with data scarcity,offer fresh strategies for the optimization of aviation maintenance practices,and chart a new course toward achieving more efficient and cost-effective maintenance schedule optimization through refined data analysis.

关键词： Small sample data Data fusion Failure rate Maintenance planning Aircraft parts

Microstructural evolution during tempering process and mechanical properties of Cr-Ni-Mo-V/Nb high strength steel

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Journal of Iron and Steel Research International 2025年第1期32卷 270-281页

作者： Zi-wei Lv jing Fan Rui Wang Zhi-qiang Yu Yan kang Yong Hu Lei-feng Tuo Jürgen Eckert Zhi-jie Yan School of Materials Science and Engineering North University of ChinaTaiyuan 030051ShanxiChina Shanxi Key Laboratory of Advanced Metal Materials for Special Environments North University of ChinaTaiyuan 030051ShanxiChina School of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024ShanxiChina Erich Schmid Institute of Materials Science Austrian Academy of SciencesLeoben 8700Austria Department of Materials Science Chair of Materials PhysicsMontanuniversitat LeobenLeoben 8700Austria

High strength steels exhibit superior mechanical properties due to the unique microstructure,which successfully solves the drawback of the inevitable strength-toughness trade-off that occurs in traditional *** we investigated the effect of matrix and precipitates on mechanical properties of Cr-Ni-Mo-V/Nb steel after water quenching and tempering(150-500℃).The results showed that the microstructure of the present steel is noticeably tuned by changing the tempering *** excellent combination of strength(a yield strength of 1308 MPa with a total elongation of 8.2%)and toughness(Charpy V-notch impact toughness of 40.5 J/cm^(2))is obtained upon tempering at 200℃.This is attributed to the lath martensite containing high dislocation density,the martensite-twin substructure,and the strengthening effects of the precipitated needle-likeε-carbides and spherical VC *** acicularε-carbides are replaced by the rod-shaped Fe_(3)C at the tempering temperature of 350℃,resulting in the remarkable deterioration in strength,hardness,and *** carbides formed at a tempering temperature of 500℃ are beneficial to the enhancement of the elongation and toughness,but the strength decreases due to the matrix softening caused by the recovery of dislocation.

关键词： High strength steel Tempering Microstructure Carbide Mechanical property

Changes in factor profiles deriving from photochemical losses of volatile organic compounds:Insight from daytime and nighttime positive matrix factorization ana

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Journal of Environmental Sciences 2025年第5期151卷 627-639页

作者： Baoshuang Liu Tao Yang Sicong kang Fuquan Wang Haixu Zhang Man Xu Wei Wang jinrui Bai Shaojie Song Qili Dai Yinchang feng Philip K.Hopke State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control&Tianjin Key Laboratory of Urban Transport Emission Research College of Environmental Science and EngineeringNankai UniversityTianjin 300350China CMA-NKU Cooperative Laboratory for Atmospheric Environment-Health Research Tianjin 300350China Beijing Make Environment Science&Technology Co. Ltd.Beijing 100083China Shijiazhuang Environmental Prediction Center Shijiazhuang 050022China Department of Public Health Sciences University of Rochester School of Medicine and DentistryRochesterNY 14642USA Institute for a Sustainable Environment Clarkson UniversityPotsdamNY 13699USA

Substantial effects of photochemical reaction losses of volatile organic compounds(VOCs)on factor profiles can be investigated by comparing the differences between daytime and nighttime dispersion-normalized VOC data resolved *** speciated VOC data measured in Shijiazhuang,China from May to September 2021 were used to conduct *** mean VOC concentration in the daytime and at nighttime were 32.8 and 36.0 ppbv,*** and aromatics concentrations in the daytime(12.9 and 3.08 ppbv)were lower than nighttime(15.5 and 3.63 ppbv),whereas that of alkenes showed the opposite *** concentration differences between daytime and nighttime for alkynes and halogenated hydrocarbonswere uniformly *** reactivities of the dominant species in factor profiles for gasoline emissions,natural gas and diesel vehicles,and liquefied petroleum gas were relatively low and their profiles were less affected by photochemical *** losses produced a substantial impact on the profiles of solvent use,petrochemical industry emissions,combustion sources,and biogenic emissions where the dominant species in these factor profiles had high *** the profile of biogenic emissions was substantially affected by photochemical loss of isoprene,the low emissions at nighttime also had an important impact on its *** losses of highly active VOC species substantially reduced their concentrations in apportioned factor *** study results were consistent with the analytical results obtained through initial concentration estimation,suggesting that the initial concentration estimation could be the most effective currently availablemethod for the source analyses of active VOCs although with uncertainty.

关键词： Volatile organic compounds Dispersion normalization Photochemical loss Factor profile Positive matrix factorization

Unlocking the power of tandem repeat variations to fine-tune rice phenotypes

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Science Bulletin 2025年第3期70卷 297-298页

作者： kang Chong Key Laboratory of Plant Molecular Physiology Institute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China

The diversity of crop phenotypes is shaped by numerous genomic *** staple cereals like rice,lots of functional variants,including quantitative trait locus(QTLs),have been identified and used to improve various crop traits(yield,quality,architecture,etc.).To breed ideal crop cultivars for agricultural production,we need more and more precise modulation of phenotypes to obtain desirable *** the past decade,genome editing techniques have enabled us to precisely change crop genome sequences,and also functional variants[1],[2],[3].

关键词： cultivar cereal precise

Extended protective effects of three dimensional cultured human mesenchymal stromal cells in a neuroinflammation model

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World Journal of Stem Cells 2025年第1期17卷 53-65页

作者： Ok-Hyeon Kim Hana kang Eun Seo Chang Younghyun Lim Young-jin Seo Hyun Jung Lee Department of Anatomy and Cell Biology College of MedicineChung-Ang UniversitySeoul 06974South Korea Department of Global Innovative Drugs Graduate School of Chung-Ang UniversitySeoul 06974South Korea Department of Life Science Chung-Ang UniversitySeoul 06974South Korea

BACKGROUND Human mesenchymal stromal cells(MSCs)possess regenerative potential due to pluripotency and paracrine ***,their stemness and immunomod-ulatory capabilities are sub-optimal in conventional two-dimensional(2D)*** To enhance the efficiency and therapeutic efficacy of MSCs,an in vivo-like 3D culture condition was *** MSCs were cultured on polystyrene(2D)or in a gellan gum-based 3D *** vitro,prostaglandin-endoperoxide synthase 2,indoleamine-2,3-dioxygenase,heme oxygenase 1,and prostaglandin E synthase gene expression was quantified by quantitative real-time polymerase chain *** were incubated with lipopolysaccharide(LPS)-treated mouse splenocytes,and prostaglandin E2 and tumor necrosis factor-alpha levels were measured by enzyme linked immuno-sorbent *** vivo,LPS was injected into the lateral ventricle of mouse brain,and MSCs were administered intravenously the next *** were sacrificed and analyzed on days 2 and *** Gellan gum polymer-based 3D culture significantly increased expression of octamer-binding transcription factor 4 and Nanog homeobox stemness markers in human MSCs compared to 2D *** 3D environment also heightened expression of cyclooxygenase-2 and heme-oxygenase 1,enzymes known for immunomodulatory functions,including production of prostaglandins and heme degradation,*** in 3D culture secreted more prostaglandin E2 and effectively suppressed tumor necrosis factor-alpha release from LPS-stimulated splenocytes and surpassed the efficiency of MSCs cultured in *** a murine neuroinflammation model,intravenous injection of 3D-cultured MSCs significantly reduced ionized calcium-binding adaptor molecule 1 and glial fibrillary acidic protein expression,mitigating chronic inflammation more effectively than 2D-cultured *** The microenvironment established in 3D culture serves as an in vivo mimetic,enhancing the immunomodulatory function of *** sugge

关键词： Mesenchymal stromal cells Three-dimensional culture Immunomodulatory function Neuroinflammation Cell therapy

Prediction of intrusive gas pores caused by resin burning in sand core for iron castings

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China Foundry 2025年第1期22卷 23-32页

作者： Ji-wu Wang Xiao-long Wang Yu-cheng Sun Yu-hang Huang Xiu-ming Chen Xiong-zhi Wu Na Li jin-wu kang Tao jing Tian-you Huang Hai-liang Yu School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Weichai Power Co. Ltd.Weifang 261061ShandongChina School of Mechanical Engineering Central South UniversityChangsha 41000China School of Materials Science and Engineering Key Laboratory for Advanced Materials Processing TechnologyTsinghua UniversityBeijing 100084China

In the production of castings,intrusive gas pore represents a kind of common defects which can lead to leakage in high gas-tightness requirement castings,such as cylinder blocks and cylinder heads for *** occurs due to the intrusion of gases generated during the resin burning of the sand core into castings during the casting ***,a gas generation and flow constitution model was established,in which the gas generation rate is a function of temperature and time,and the flow of gas is controlled by the gas release,conservation,and Darcy's *** heat transfer and gas flow during casting process was numerically *** dangerous point of cores is firstly identified by a virtual heat transfer method based on the similarity between heat transfer and gas flow in the sand *** gas pores in castings are predicted by the gas pressure,the viscosity and state of the melt for these dangerous *** distinct sand core structures were designed and used for the production of iron castings,and the simulated gas pore results were validated by the obtained castings.

关键词： gas pore numerical simulation iron casting sand core resin

Residential Energy Scheduling With Solar Energy Based on Dyna Adaptive Dynamic Programming

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IEEE/CAA Journal of Automatica Sinica 2025年第2期12卷 403-413页

作者： kang Xiong Qinglai Wei Hongyang Li the Institute of Systems Engineering Macau University of Science and Technology IEEE the State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of Automation Chinese Academy of Sciences the School of Artificial Intelligence University of Chinese Academy of Sciences

Learning-based methods have become mainstream for solving residential energy scheduling problems. In order to improve the learning efficiency of existing methods and increase the utilization of renewable energy, we propose the Dyna actiondependent heuristic dynamic programming(Dyna-ADHDP)method, which incorporates the ideas of learning and planning from the Dyna framework in action-dependent heuristic dynamic programming. This method defines a continuous action space for precise control of an energy storage system and allows online optimization of algorithm performance during the real-time operation of the residential energy model. Meanwhile, the target network is introduced during the training process to make the training smoother and more efficient. We conducted experimental comparisons with the benchmark method using simulated and real data to verify its applicability and performance. The results confirm the method's excellent performance and generalization capabilities, as well as its excellence in increasing renewable energy utilization and extending equipment life.

关键词： Adaptive dynamic programming (ADP) dynamic residential scenarios optimal residential energy management smart grid

Encapsulating perovskite quantum dots into 3D COF for visible light-driven CO2 reduction

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Science China Chemistry 2025年

作者： Xinxin Wang Yucheng jin Xiya Yang Qingyu Luan Tianyu Wang Dongdong Qi kang Wang Jianzhuang Jiang College of Chemistry and Materials Science Anhui Normal University Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline Materials Department of Chemistry and Chemical Engineering School of Chemistry and Biological EngineeringUniversity of Science and Technology Beijing

Lead halide perovskite quantum dots（LHP QDs） have been revealed to possess great potential in photocatalytic applications including CO2reduction, which however suffer from poor stability. Herein, a high crystalline hydrazine-linked three-dimensional（3D） covalent organic framework, USTB-17, was fabricated from the reaction between 12-connected building block and 4-connected 3,5,7-tetrakis（4-aldophenyl）-adamantane. Post-modification with Ni2+affords the metallic framework USTB-17（Ni）followed by sequential deposition of the CH3NH2PbI3（MAPbI3） perovskite QDs into its pores, generating the USTB-17（Ni）@MAPbI3composite. Powder X-ray diffraction analysis together with theoretical simulations and transmission electron microscopy discloses the crystalline nature of USTB-17, USTB-17（Ni）, and USTB-17（Ni）@MAPbI3with an unprecedented noninterpenetrated hpt topology. The close contact of QDs inside the COF pores with the Ni catalytic site locating at the pore surface of COF allows a rapid transfer of the photogenerated electrons in QDs to the Ni catalytic sites, enhancing the photocatalytic activity for CO2reduction. This endows USTB-17（Ni）@MAPbI3with efficient photocatalysis performance for photocatalytic CO2reduction with CO generation rate of 365 μmol g-1h-1and CO selectivity up to 96% under visible-light irradiation, 7 times higher than that of USTB-17（Ni）. After four cycles of reactions, the photocatalytic CO generation rate remains almost unchanged, demonstrating its excellent cycle stability.

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