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退火条件对电沉积制备铜铟镓硒薄膜品质的影响（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2018年第5期19卷 399-408页

作者： Jing-yu QU zheng-fei GUO Kun PAN Wei-wei ZHANG Xue-jin WANG College of Science China Agricultural University

目的:退火条件直接影响着电沉积制备的铜铟镓硒薄膜品质,而薄膜品质决定着最终得到器件的转换效率。本实验在不同退火条件下对薄膜进行处理,得出退火条件对薄膜各项表征指标的影响规律,并根据观察到的规律改善退火工艺,以提高铜铟镓硒... 详细信息

目的:退火条件直接影响着电沉积制备的铜铟镓硒薄膜品质,而薄膜品质决定着最终得到器件的转换效率。本实验在不同退火条件下对薄膜进行处理,得出退火条件对薄膜各项表征指标的影响规律,并根据观察到的规律改善退火工艺,以提高铜铟镓硒薄膜品质。创新点:目前利用水溶液电沉积制备的铜铟镓硒薄膜太阳能电池转换效率不高,而退火是制作此电池的关键步骤之一。本文研究了退火温度和升温速率对薄膜品质的影响,分析其可能原因及退火过程发生的反应,并制备出了理想的高品质薄膜。方法:1.在水溶液中利用电沉积法制备出铜铟镓硒薄膜前驱体。2.对前驱体进行退火处理,并针对不同的样品采用不同的退火温度和升温速率。3.利用X射线衍射(XRD)、拉曼光谱(Raman)、扫描电子显微镜(SEM)、X射线荧光光谱(XRF)对薄膜进行表征,分析不同退火条件对结果的影响规律。结论:1.退火温度的影响:退火温度由450°C升高到580°C时,得到的薄膜结晶性越来越好,晶粒边界越来越不明显,Cu/(In+Ga)的比例逐渐升高,说明高温下(≥450°C)金属铟和镓较易挥发;实验中还发现Cu-Se化合物的总含量随退火温度的升高而降低。2.升温速率的影响:退火速率越高,薄膜结晶性越好;快速升温时薄膜中Cu/(In+Ga)的比例略低于慢速升温时的样品,而Ga/(In+Ga)的比例几乎不变,说明快速升温可以减少In和Ga的挥发。

关键词：铜铟镓硒薄膜电沉积退火条件拉曼光谱

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面向网络空间防御的对抗机器学习研究综述

自动化学报 2022年第7期48卷 1625-1649页

作者：余正飞闫巧周鋆国防科技大学系统工程学院长沙410073 国防科技大学信息系统工程重点实验室长沙410073 深圳大学计算机与软件学院深圳518061

机器学习以强大的自适应性和自学习能力成为网络空间防御的研究热点和重要方向.然而机器学习模型在网络空间环境下存在受到对抗攻击的潜在风险,可能成为防御体系中最为薄弱的环节,从而危害整个系统的安全.为此科学分析安全问题场景,从... 详细信息

机器学习以强大的自适应性和自学习能力成为网络空间防御的研究热点和重要方向.然而机器学习模型在网络空间环境下存在受到对抗攻击的潜在风险,可能成为防御体系中最为薄弱的环节,从而危害整个系统的安全.为此科学分析安全问题场景,从运行机理上探索算法可行性和安全性,对运用机器学习模型构建网络空间防御系统大有裨益.全面综述对抗机器学习这一跨学科研究领域在网络空间防御中取得的成果及以后的发展方向.首先,介绍了网络空间防御和对抗机器学习等背景知识;其次,针对机器学习在网络空间防御中可能遭受的攻击,引入机器学习敌手模型概念,目的是科学评估其在特定威胁场景下的安全属性;然后,针对网络空间防御的机器学习算法,分别论述了在测试阶段发动规避攻击、在训练阶段发动投毒攻击、在机器学习全阶段发动隐私窃取的方法,进而研究如何在网络空间对抗环境下,强化机器学习模型的防御方法;最后,展望了网络空间防御中对抗机器学习研究的未来方向和有关挑战.

关键词：网络空间防御对抗机器学习投毒攻击规避攻击对抗样本

A fishbone lodged in the tongue:a case report

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Clinical Research Communications 2024年第4期7卷 18-20页

作者： Na Wang Zhi-Hua Hu yu-fei zheng Zhen Zeng Wei Luo Hubei Provincial Key Research Base for Humanities and Social Sciences Rural Education and Cultural Development Center Xianning 437100China Xianning Medical College Hubei University of Science and TechnologyXianning 437100China Thyroid and Breast Surgery Xianning Central HospitalXianning 437100China.

Fishbones are relatively common foreign bodies found in the throat,with the tonsils and tongue base being frequent locations for them to ***,foreign bodies within the tongue are clinically infrequent,and their displacement is intricately linked to the shape of the object,duration of lodgement,and the fiber orientation during tongue muscle *** article reports a case of a foreign body lodged in the tongue,treated at Xianning Central Hospital in April 2024.

关键词： fishbone foreign body tongue

A case of tiny foreign body hidden in the neck for 27 years

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Clinical Research Communications 2023年第3期6卷 7-9页

作者： Ming Huang Na Wang Zhi-Hua Hu yu-fei zheng Shuang-Lin Qin Hubei Provincial Key Research Base for Humanities and Social Sciences Rural Education and Cultural Development Center Hubei University of Science and TechnologyXianning 437100China Xianning Medical College Hubei University of Science and TechnologyXianning 437100China Thyroid and Breast Surgery Xianning Central HospitalXianning 437100China

Neck trauma has the characteristics of diversity,complexity,and *** injuries generally require debridement and suturing or symptomatic *** severe cases,acute laryngeal obstruction,subcutaneous emphysema,severe deformation and collapse of laryngeal and tracheal cartilage,or damage to adjacent organs may *** not diagnosed in a timely manner or mishandled,it can endanger the patient’s life or leave *** foreign body residue is caused by head and neck trauma,a reasonable judgment should be made based on the patient’s condition and corresponding measures should be *** localization of foreign bodies before and during surgery,as well as appropriate surgical methods,are key to ensuring successful *** article reports a case of a small foreign body in the neck admitted to Xianning Central Hospital at the end of January 2023.

关键词： neck trauma foreign body metal nodule

Personalized federated few-shot node classification

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Science China(Information Sciences) 2025年第1期68卷 204-218页

作者： yunfeng ZHAO Xintong HE Guoxian yu Jun WANG Yongqing zheng Carlotta DOMENICONI School of Software Shandong University Joint SDU-NTU Centre for Artificial Intelligence Research Shandong University Department of Mathematics National University of Singapore Department of Computer Science George Mason University

Personalized federated learning(PFL) aims to train customized models for individual clients in a decentralized setting, with the account of non-independent and identically distributed data across clients. However, most PFL methods adopt uniform classification layers for diverse clients and give rise to error-prone predictions, due to the task heterogeneity notably prominent in decentralized graph data scenarios. Although some PFL solutions setup client-specific classification layers for each client and optimize them only locally, they are corrupted with limited local training data. We propose an innovative solution called federated parameter decoupling and node augmentation(Fed PANo) to address these problems and to achieve personalized federated few-shot node classification, which is a prevalent and challenging but unexplored topic. Specifically, Fed PANo first separates the local model into the GNN and classifier to handle unique client-specific task variations. The GNN is trained through federated learning to capture shared knowledge of graph nodes across clients, while the classifier is custom-designed and trained individually for each client. Additionally, a generic classifier shared among clients is adopted to encourage the GNN's grasp of shared information. Then Fed PANo further proposes the node generator along with its local and collaborative training strategies to deal with the node scarcity of clients. Extensive experimental results on benchmark datasets confirm that Fed PANo outperforms eight competitive baselines across different settings.

关键词： personalized federated learning few-shot learning node classification task heterogeneity parameter decoupling node augmentation

Small modifications of endo-functionalized cavities lead to large changes in molecular interaction in water

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Science China Chemistry 2025年第1期68卷 369-376页

作者： Song-Meng Wang Hao Nian Yan-Fang Wang Li-Shuo zheng yu-Tao zheng Yi-Wei Dong Liping Huang Xiaoping Wang Wei Jiang Liu-Pan Yang Department of Chemistry Southern University of Science and Technology School of Chemistry and Pharmaceutical Sciences State Key Laboratory for Chemistry and Molecular Engineering of Medicinal ResourcesGuangxi Normal University School of Pharmaceutical Science Hengyang Medical School University of South China

Studying molecular recognition in aqueous environments is crucial for understanding biological processes. Herein, we present a series of N-doped endo-functionalized anthracene-based cavities by introducing inward-directed pyridine units. The subtle modifications can significantly affect the binding properties of these receptors, which is similar to the mutations in biological systems. Combining theoretical calculations and molecular recognition experiments demonstrated that these “mutations” have an impact on the hydrophobicity and charge distribution of the hosts, consequently significantly influencing molecular *** is crucial for understanding the intricate mechanisms of molecular-level interactions in biological receptors.

关键词： host-guest interaction hydrophobic effect endo-functionalized cavity mutation pyridine

Influence of introducing Zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 147-153页

作者： Junjie Li Wenbo yu Zhenyu Sun Weichen zheng Liangwei Zhang Yanling Xue Wenning Liu Shoumei Xiong Center of Materials Science and Engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Traffic&Transportation Engineering Central South UniversityChangsha 410075China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical *** introduction of Ce resulted in the poisoning effect and reduced mechanical properties.

关键词： aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment

Hypoxia-preconditioned bone marrow-derived mesenchymal stem cells protect neurons from cardiac arrest-induced pyroptosis

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Neural Regeneration Research 2025年第4期20卷 1103-1123页

作者： Xiahong Tang Nan zheng Qingming Lin Yan You zheng Gong Yangping Zhuang Jiali Wu yu Wang Hanlin Huang Jun Ke Feng Chen Shengli Clinical Medical College of Fujian Medical University Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Emergency Fujian Provincial HospitalFuzhouFujian ProvinceChina Fujian Provincial Key Laboratory of Emergency Medicine FuzhouFujian ProvinceChina The Second Department of Intensive Care Unit Fujian Provincial Hospital South BranchFuzhouFujian ProvinceChina

Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological *** preconditioning has been shown to improve migration and survival of bone marrow–derived mesenchymal stem cells and reduce pyroptosis after cardiac arrest,but the specific mechanisms by which hypoxia-preconditioned bone marrow–derived mesenchymal stem cells protect against brain injury after cardiac arrest are *** this end,we established an in vitro co-culture model of bone marrow–derived mesenchymal stem cells and oxygen–glucose deprived primary neurons and found that hypoxic preconditioning enhanced the protective effect of bone marrow stromal stem cells against neuronal pyroptosis,possibly through inhibition of the MAPK and nuclear factor κB ***,we transplanted hypoxia-preconditioned bone marrow–derived mesenchymal stem cells into the lateral ventricle after the return of spontaneous circulation in an 8-minute cardiac arrest rat model induced by *** results showed that hypoxia-preconditioned bone marrow–derived mesenchymal stem cells significantly reduced cardiac arrest–induced neuronal pyroptosis,oxidative stress,and mitochondrial damage,whereas knockdown of the liver isoform of phosphofructokinase in bone marrow–derived mesenchymal stem cells inhibited these *** conclude,hypoxia-preconditioned bone marrow–derived mesenchymal stem cells offer a promising therapeutic approach for neuronal injury following cardiac arrest,and their beneficial effects are potentially associated with increased expression of the liver isoform of phosphofructokinase following hypoxic preconditioning.

关键词： bone marrow–derived mesenchymal stem cells cardiac arrest cardiac resuscitation hypoxic preconditioning liver isoform of phosphofructokinase mitochondria neuroinflammation oxidative stress pyroptosis reactive oxygen species

Dual-ligand chiral MOFs exhibiting circularly polarized room temperature phosphorescence for anti-counterfeiting

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Science China Chemistry 2025年

作者： Hongrui zheng Qingqing Wang Xinchao Wang fei Wang Shangda Li Jian Zhang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fujian Key Laboratory of Polymer Materials College of Chemistry and Materials Science Fujian Normal University

Advanced chiral optical materials exhibiting circularly polarized room-temperature phosphorescence（CPRTP） possess significant research value. This study facilitates the synthesis of chiral metal-organic frameworks（CMOFs） with good CPRTP performance by implementing a dual-ligand strategy. By self-assembling the luminescent ligand H2BIIM with the chiral ligands L-or D-H2IDPA in the presence of Zn（II） ions, two robust three-dimensional（3D） CMOFs were successfully constructed. These complexes demonstrated intense fluorescence and exhibited prolonged yellow room-temperature phosphorescence（RTP） with a duration of up to 6 s. Notably, they exhibited both circularly polarized fluorescence(glum= ±7.57 × 10-3) and CPRTP(glum=±2.68 × 10-3). These unique properties were effectively utilized in the creation of multi-color anti-counterfeiting patterns,underscoring their promising potential for a wide range of applications.

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