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Highly Efficient and Recyclable Catalyst HBF_4·SiO_2 Catalyzed Synthesis of β-Enamino Compounds Under Solvent-free Conditions

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Chemical Research in Chinese Universities 2011年第5期27卷 792-794页

作者： GAO Han JIA xu-dong duan Hai-feng LIN Ying-jie GAO Jun-gang LIANG Da-peng WU Mao-cheng Department of Organic Chemistry College of Chemistry dilin University Changchun 130012 l~ R. China

Fluoroboric acid adsorbed on silica-gel（HBF4·SiO2） has been found to be an extremely efficient and recyclable catalyst for the preparation of β-enaminones and β-enamino esters under solvent-free conditions.

关键词： β-Enaminone β-Enamino ester HBF4·SiO2 Solvent-free condition

Microstructures and Properties of Biomedical Mg-Zn-Sn-Zr Rolled Alloys

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 766-773页

作者：周生刚 ZHANG Daxin xu Yang duan Jihao LI Tao LIU Junfeng WANG Peng 曹勇 Faculty of Material Science and Engineering Kunming University of Science and TechnologyKunming 650093China

The as-cast Mg-2.0Zn-1.5Sn-xZr(x=0,0.4,0.6,0.8,1.0 wt%)alloy was rolled with the pressure less than 5%each *** microstructure,mechanical properties,corrosion properties and biocompatibility of the alloy were *** microstructure of the alloy was observed and analyzed by scanning electron microscope,and the tensile test was carried out by universal tensile *** corrosion resistance of the alloy in Hank's solution was studied by hydrogen evolution experiment and electrochemical test,and the biocompatibility of the alloy was tested by L929 *** results show that Mg-2Zn-1.5Sn-xZr alloy has excellent mechanical *** elongation of Mg-2Zn-1.5Sn-xZr alloy decreases with the increase of Zr content,but the tensile strength first increases and then decreases with the increase of Zr *** the Zr content is 0.8 wt%,the maximum tensile strength of the alloy is 235 *** results of hydrogen evolution experiment and electrochemical analysis show that the corrosion resistance of the alloy is the best when the Zr content is 0.8 wt%,and all the five alloys have high *** conclusion,the rolled alloy has good properties and has broad application prospects in the field of biomaterials.

关键词： magnesium alloy corrosion performance mechanical properties biocompatibility

Liquid-like polymer lubricating surfaces:Mechanism and applications

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Nano Research 2024年第2期17卷 476-491页

作者： Dagui Wang Jinglong Yang Junchang Guo Zhijuan duan Deihui Wang Fan Xia Fei Deng xu Deng Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China State Key Laboratory of Biogeology and Environmental Geology Engineering Research Center of Nano-Geomaterials of Ministry of EducationFaculty of Materials Science and ChemistryChina University of GeosciencesWuhan 430070China Department of Nephrology Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengdu 610054China Department of Nephrology Sichuan Provincial People’s Hospital Jinniu HospitalChengdu Jinniu District People’s HospitalChengdu 610054China Shenzhen Institute for Advanced Study University of Electronic Science and Technology of ChinaShenzhen 518110China

Liquid-like polymer lubricating surfaces(LPLSs)are solid substrates with highly flexible polymer chains grafted via covalent *** unique modification enables ultralow contact-angle hysteresis,repellency of various liquids and bulk ice,and *** distinctive wettability and universality of LPLSs have potential applications in liquid motion,biological detection,and environmental *** this review,we summarize the mechanisms,preparation,and applications of *** discuss the wettability and lubrication mechanisms of liquid droplets on *** then categorize LPLS fabrication into“grafted onto”and“grafted from”groups,depending on the type of *** highlight representative applications with recent developments in anti-complex liquid,anti-icing,anti-biological adhesions,biosensing,and photocatalytic ***,we discuss future challenges and outlooks for LPLSs.

关键词： liquid-like polymer surface lubricating wettability

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一阶伪线性系统的模型参考输出跟踪控制

控制与决策 2017年第8期32卷 1409-1414页

作者：许刚段广仁哈尔滨工业大学控制理论与制导技术研究中心哈尔滨150001

针对伪线性系统的模型参考输出跟踪问题,设计伪线性系统的模型参考跟踪策略.控制器分为两部分,其一为反馈镇定控制器,保证闭环系统是渐近稳定的;另一为前馈补偿控制器,通过求解基于控制器存在条件建立的方程组得到控制器的参量矩阵,使... 详细信息

针对伪线性系统的模型参考输出跟踪问题,设计伪线性系统的模型参考跟踪策略.控制器分为两部分,其一为反馈镇定控制器,保证闭环系统是渐近稳定的;另一为前馈补偿控制器,通过求解基于控制器存在条件建立的方程组得到控制器的参量矩阵,使得闭环系统的输出渐近跟踪参考系统的输出,且当系统中存在时变系数时方法仍是有效的,控制器中保有部分自由度可以进一步利用,以提高具体控制任务所需的系统性能.数值仿真验证了所提出方法的有效性.

关键词：伪线性系统模型参考跟踪特征结构配置输出反馈自由度

Super-high bed sintering for iron ores: inhomogeneous phenomena and its mechanism during mineralizing

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Journal of Iron and Steel Research International 2024年第8期31卷 1850-1860页

作者： Hui-bo Liu Liang-ping xu Xi-duan Yang Zhong-lin Dong Qiang Zhong Guang-hui Li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina

The inhomogeneous sinter properties in super-high bed sintering have been reported in our previous *** inves-tigate the reasons for the inhomogeneous phenomena,detailed sampling and analysis of mixed material bed and sintered bed in super-high bed sintering plant were *** results indicated that the higher porosity and thinner dendrite of silico-ferrite of calcium and aluminum in the upper layer as well as dense structure and higher secondary hematite content in the lower layer led to the heterogeneities of mechanical strength and reduction properties exceeding 20%and 10%,*** the bed top downward,the basicity of mixed material decreased from 2.13 to 1.68 because the average particle size increased from 2.65 to 4.56 *** and fuels gathered in finer particles(-3 mm)of mixed material,and the-3 mm particles of mixed material generated more liquid phase than+3 mm *** heat input of super-high sintering bed was inhomogeneous due to the heat accumulation effect and unreasonable fuel *** inhomo-geneous sintering heat condition in sintering bed resulted in the different quantities and properties of liquid *** inhomogeneous quantities and properties of liquid phase that were influenced by inhomogeneous distribution of chemical composition,particle size,and heat input led to inhomogeneous mineralizing *** mineralizing condition is the key for homogeneous super-high bed sintering.

关键词： Iron ore Super-high bed sintering Mineralization Material segregation Heat accumulation

A survey on large language model(LLM)security and privacy:The Good,The Bad,and The Ugly

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High-Confidence Computing

High-Confidence Computing 2024年第2期4卷 12-32页

作者： Yifan Yao Jinhao duan Kaidi xu Yuanfang Cai Zhibo Sun Yue Zhang Department of Computer Science Drexel UniversityPhiladelphiaPA 19104USA

Large Language Models(LLMs),such as ChatGPT and Bard,have revolutionized natural language understanding and *** possess deep language comprehension,human-like text generation capabilities,contextual awareness,and robust problem-solving skills,making them invaluable in various domains(e.g.,search engines,customer support,translation).In the meantime,LLMs have also gained traction in the security community,revealing security vulnerabilities and showcasing their potential in security-related *** paper explores the intersection of LLMs with security and ***,we investigate how LLMs positively impact security and privacy,potential risks and threats associated with their use,and inherent vulnerabilities within *** a comprehensive literature review,the paper categorizes the papers into‘‘The Good’’(beneficial LLM applications),‘‘The Bad’’(offensive applications),and‘‘The Ugly’’(vulnerabilities of LLMs and their defenses).We have some interesting *** example,LLMs have proven to enhance code security(code vulnerability detection)and data privacy(data confidentiality protection),outperforming traditional ***,they can also be harnessed for various attacks(particularly user-level attacks)due to their human-like reasoning *** have identified areas that require further research *** example,Research on model and parameter extraction attacks is limited and often theoretical,hindered by LLM parameter scale and *** instruction tuning,a recent development,requires more *** hope that our work can shed light on the LLMs’potential to both bolster and jeopardize cybersecurity.

关键词： Large Language Model(LLM) LLM security LLM privacy ChatGPT LLM attacks LLM vulnerabilities

在线化学蒸气发生-电感耦合等离子体原子发射光谱法测定废催化剂中的微量铑

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分析化学 2010年第3期38卷 421-424页

作者：段旭川天津师范大学化学与生命学院天津市细胞遗传与分子调控重点实验室

使用电感耦合等离子原子发射光谱(ICP-AES)研究了贵金属铑和NaBH4在酸性水溶液中的化学蒸气发生反应的条件,并测定了有机合成催化剂中的铑。研究结果表明:在NaBH4和样品溶液流速为2mL/min、废液排放流速为6mL/min的条件下的最佳蒸气发... 详细信息

使用电感耦合等离子原子发射光谱(ICP-AES)研究了贵金属铑和NaBH4在酸性水溶液中的化学蒸气发生反应的条件,并测定了有机合成催化剂中的铑。研究结果表明:在NaBH4和样品溶液流速为2mL/min、废液排放流速为6mL/min的条件下的最佳蒸气发生条件为:载气流速0.4L/min、HNO3浓度为1.0mol/L、NaBH4浓度为1.2%(m/V)。研究中获得的铑化学蒸气进样效率是常规的气动雾化进样效率的2.7倍;检出限是6.9μg/L,略优于气动雾化法;线性范围20～1500μg/L;线性相关系数是0.9986;RSD是1.6%。样品分析加标回收率分别是94%和97%。用本法测得的样品值与原子吸收法的测得值吻合很好。

关键词：化学蒸气发生电感耦合等离子体原子发射光谱铑

Nickel-catalyzed carbonylative four-component 1,4-dicarbofunctionalization of 1,3-enynes

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Science China Chemistry 2024年第6期67卷 2029-2038页

作者： Yan Zhao Qi-Chao Shan Hong Xin Pin Gao xu Yang Xin-Hua duan Li-Na Guo Department of Chemistry School of ChemistryXi’an Key Laboratory of Sustainable Energy Material Chemistry and Engineering Research Center of Energy StorageMaterials and DevicesMinistry of EducationXi’an Jiaotong UniversityXi’an710049China School of Electrical Engineering Xi’an Jiaotong UniversityXi’an710049China

An efficient Ni-catalyzed four-component 1,4-carbocarbonylation of 1,3-enynes with activated alkyl halides and arylboronic acids under atmospheric pressure of CO is *** tuning the electronic and steric effects of alkyl radicals,both electronrich and electron-deficient 1,3-enynes were compatible with this *** protocol features mild conditions,broad substrate scope,excellent functional group compatibility and facile gram-scale synthesis,providing a practical approach to the quaternary carbon center-containing allenyl *** study revealed that the acyl-NiIIspecies plays an important role in both the coupling and the alkyl radical generation processes.

关键词： Ni catalysis four-component 1 4-carbocarbonylation 1 3-enynes

Wear-resistant Ag-MAX phase 3D interpenetrating-phase composites:Processing,structure,and properties

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Nano Research 2024年第2期17卷 806-819页

作者： Yu Guo Xi Xie Zengqian Liu Longchao Zhuo Jian Zhang Shaogang Wang Qiqiang duan Qing Jia Dake xu Weihai xue Deli duan Filippo Berto Zhefeng Zhang Rui Yang Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048China Electrobiomaterials Institute Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education)Northeastern UniversityShenyang 110819China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Department of Chemical Engineering Materials and EnvironmentSapienza University of RomeRoma 00185Italy

Electrical contact materials are generally Ag-or Cu-based composites and play a critical role in ensuring the reliability and efficiency of electrical equipments and electronic *** MAX(M is an early transition metal,A is an element from III or IV main groups,and X is carbon or/and nitrogen)phase ceramics display a unique combination of properties and may serve as an ideal reinforcement phase for electrical contact *** biological materials evolved in nature generally exhibit three-dimensional(3D)interpenetrating-phase architectures,which may offer useful inspiration for the architectural design of electrical contact ***,a series of bi-continuous Ag-Ti_(3)SiC_(2) MAX phase composites with high ceramic contents exceeding 50 vol.%and having micron-and ultrafine-scaled 3D interpenetrating-phase architectures,wherein both constituents were continuous and mutually interspersed,were exploited by pressureless infiltration of Ag melt into partially sintered Ti_(3)SiC_(2) *** mechanical and electrical properties as well as the friction and wear performance of the composites were investigated and revealed to be closely dependent on the ceramic contents and characteristic structural *** composites exhibited a good combination of properties with high hardness over 2.3 GPa,high flexural strength exceeding 530 MPa,decent fracture toughness over 10 MPa·m^(1/2),and good wear resistance with low wear rate at an order of 10^(-5)mm^(3)/(N·m),which were much superior compared to the counterparts made by powder metallurgy *** particular,the hardness,electrical conductivity,strength,and fracture toughness of the composites demonstrated a simultaneous improvement as the structure was refined from micron-to ultrafine-scales at equivalent ceramic *** good combination of properties along with the facile processing route makes the Ag-Ti_(3)SiC_(2)3D interpenetrating-phase composites appealing for electrical contact applicatio

关键词： three-dimensional(3D)interpenetrating-phase architecture Ag-MAX(M=early transition metal A=element from III or IV main groups and X=carbon or/and nitrogen)phase composites melt infiltration electrical contact materials mechanical