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Journal of Advanced Ceramics 2021年第3期10卷 578-586页

作者： lin-kun SHI Xiaobing ZHOU Jian-Qing DAI Ke CHEN Zhengren HUANG Qing HUANG Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China Engineering Laboratory of Advanced Energy Materials Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China

A nano-laminated Y_(3)Si_(2)C_(2) ceramic material was successfully synthesized via an in situ reaction between YH_(2)and SiC using spark plasma sintering technology.A MAX phase-like ternary layered structure of Y_(3)Si_(2)C_(2) was observed at the atomic-scale by high resolution transmission electron *** lattice parameters calculated from both X-ray diffraction and selected area electron diffraction patterns are in good agreement with the reported theoretical *** nano-laminated fracture of kink boundaries,delamination,and slipping were observed at the tip of the Vickers *** elastic modulus and Vickers hardness of Y_(3)Si_(2)C_(2) ceramics(with 5.5 wt%Y_(2)O_(3)) sintered at 1500℃were 156 and 6.4 GPa,*** corresponding values of thermal and electrical conductivity were 13.7 W·m^(-1)·K^(-1) and 6.3×10^(5)S·m^(-1),respectively.

关键词： Y3Si_(2)C_(2) rare earth silicide carbides spark plasma sintering(SPS) ternary layered structure ceramic properties

DECAY FREQUENCY SPECTRA:INTEGRAL TRANSFORM OF NONlinEAR PROCESS TIME DOMAIN SIGNALS

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Chinese Chemical Letters 1991年第1期2卷 91-94页

作者： Shu-kun lin Laboratorium für organische Chemie Eidgenossische Technische Hochschule Zürich Universitatsstrasse 16 CH-8092 ZürichSwitzerland

Decay frequency(DF)spectra are defined as spectral distribution of decay constants with oscillatory frequency as linewidth contributor.A mathematical strategy of integral transformation to construct DF spectra is *** ... 详细信息

关键词： line DECAY FREQUENCY SPECTRA

Chemical order-disorder nanodomains in Fe3Pt bulk alloy

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National Science Review 2022年第12期9卷 211-219页

作者： Qiang Li Yang Ren Qinghua Zhang lin Gu Qingzhen Huang Hui Wu Jing Sun Yili Cao kun lin Xianran Xing Beijing Advanced Innovation Center for Materials Genome Engineering Institute of Solid State Chemistry University of Science and Technology Beijing X-Ray Science Division Argonne National Laboratory Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences NIST Center for Neutron Research National Institute of Standards and Technology

Chemical ordering is a common phenomenon and highly correlated with the properties of solid *** means of the redistribution of atoms and chemical bonds,it invokes an effective lattice adjustment and tailors corresponding physical *** date,however,directly probing the 3D interfacial interactions of chemical ordering remains a big *** this work,we deciphered the interlaced distribution of nanosized domains with chemical order/disorder in Fe3pt bulk *** F-STEM images evidence the existence of such *** reverse Monte Carlo method with the X-ray pair distribution function data reveal the 3D distribution of local structures and the tensile effect in the disordered domains at the single-atomic *** chemical bonding around the domain boundary changes the bonding feature in the disordered side and reduces the local magnetic moment of Fe *** results in a suppressed negative thermal expansion and extended temperature range in Fe3Pt bulk alloy with *** study demonstrates a local revelation for the chemical order/disorder nanodomains in bulk *** understanding gained from atomic short-range interactions within the domain boundaries provides useful insights with regard to designing new functional compounds.

关键词： Fe3Pt alloy chemical order nanodomain local structure pair distribution function

Tool wear mechanisms in axial ultrasonic vibration assisted milling in-situ TiB2/7050Al metal matrix composites

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Advances in Manufacturing 2020年第2期8卷 252-264页

作者： Xiao-Fen Liu Wen-Hu Wang Rui-Song Jiang Yi-Feng Xiong kun-Yang lin School of Mechanical Engineering Northwestern Polytechnical UniversityXi'an 710072People's Republic of China School of Aeronautics and Astronautics Sichuan UniversityChengdu 610065People's Republic of China

The in-situ TiB2 particle reinforced aluminum matrix composites are materials that are difficult to machine,owing to hard ceramic particles in the *** the milling process,the polycrystalline diamond(PCD)tools are used for machining these materials instead of carbide cutting tools,which significantly increase the machining *** this study,ultrasonic vibration method was applied for milling in-situ TiB2/7050A1 metal matrix composites using a TiAIN coated carbide end milling *** completely understand the tool wear mechanism in ultrasonic-vibration assisted milling(UAM),the relative motion of the cutting tool and interaction of workpiecetool-chip contact interface was analyzed in ***,a comparative experimental study with and without ultrasonic vibration was carried out to investigate the infuences of ultrasonic vibration and cutting parameters on the cutting force,tool life and tool wear *** results show that the motion of the cutting tool relative to the chip changes periodically in the helical direction and the separation of tool and chip occurs in the transverse direction in one vibration period,in ultrasonic vibration assisted cutting.I arge instantaneous acceleration can be obtained in axial ultrasonic vibration *** cutting force in axial direction is significantly reduced by 42%-57%,40%--57%and 44%-54%,at different cutting speeds,feed rates and cutting depths,respectively,compared with that in conventional ***,the tool life is prolonged approximately 2--5 times when the ultrasonic vibration method is *** tool wear pattern microcracks are only found in *** might be of great importance for future research in order to understand the cutting mechanisms in UAM of in-situ TiB2/7050A1 metal matrix composites.

关键词： Aluminum matrix composites Ultrasonic vibration Milling Cutting force Tool wear

Two-Stage High-Efficiency Encryption Key Update Scheme for LoRaWAN Based IoT Environment

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Computers, Materials & Continua 2022年第10期73卷 547-562页

作者： kun-lin Tsai Li-Woei Chen Fang-Yie Leu Chuan-Tian Wu Department of Electrical Engineering Tunghai UniversityTaichung407Taiwan Research Center for Smart Sustainable Circular Economy Tunghai UniversityTaichung407Taiwan Department of Computer and Information Sciences Chinese Military AcademyKaohsiung830Taiwan Department of Computer Science Tunghai UniversityTaichung407Taiwan Emergency Response Management Center Industry-Academia Collaboration and University Extension DivisionMing-Chuan UniversityTaipei111Taiwan

Secure data communication is an essential requirement for an Internet of Things(IoT)*** in Industrial Internet of Things(IIoT)and Internet of Medical Things(IoMT)systems,when important data are hacked,it may induce property loss or life *** though many IoTrelated communication protocols are equipped with secure policies,they still have some security weaknesses in their IoT *** is one of the low power wide-area network protocols,and it adopts Advanced Encryption Standard(AES)to provide message integrity and ***,LoRaWAN’s encryption key update scheme can be further *** this paper,a Two-stage High-efficiency LoRaWAN encryption key Update Scheme(THUS for short)is proposed to update LoRaWAN’s root keys and session keys in a secure and efficient *** THUS consists of two stages,i.e.,the Root Key Update(RKU)stage and the Session Key Update(SKU)stage,and with different update frequencies,the RKU and SKU provide higher security level than the normal LoRaWAN specification does.A modified AES encryption/decryption process is also utilized in the THUS for enhancing the security of the *** security analyses demonstrate that the THUS not only protects important parameter during key update stages,but also satisfies confidentiality,integrity,and mutual ***,The THUS can further resist replay and eavesdropping attacks.

关键词： Key update AES LoRaWAN IoT security high efficiency

The Reaction of Tanshinones with Amines

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Chinese Chemical Letters 2003年第6期14卷 557-560页

作者： lin kun AN Xian Zhang BU Hai Qiang WU Xin Dong GUO lin MA Lian Quan GU School of Chemistry and Chemical Engineering Sun Yat-Sen UniversityGuangzhou 510275

The reaction of cryptotanshinone and tanshinone IIA with several biogenic amine metabolites involved in the pathogenic pathways of HE were investigated and eight 1,2,3,4- tetrahydrophenanthrene derivatives, 2-6 and 8-... 详细信息

关键词： Cryptotanshinone tanshinone IIA biogenic amines.

基于组合权重的文一路地下空间开发适宜性评价

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科学技术与工程 2024年第20期24卷 8804-8812页

作者：孙雅珍戚亚茹杨大勇胡智王金昌林坤沈阳建筑大学交通与测绘工程学院沈阳110168 浙江省交通运输科学研究院杭州310039 浙江大学建筑工程学院杭州310058 浙江大学平衡建筑研究中心杭州310058

对地下空间开发适宜性进行科学、合理的评价,是避免地下空间资源浪费,保证其健康可持续发展的前提。基于地形地貌、工程地质、水文地质、不良地质作用和建设现状构建地下空间开发适宜性评价指标体系,通过数值模拟确定盾构隧道施工的影... 详细信息

对地下空间开发适宜性进行科学、合理的评价,是避免地下空间资源浪费,保证其健康可持续发展的前提。基于地形地貌、工程地质、水文地质、不良地质作用和建设现状构建地下空间开发适宜性评价指标体系,通过数值模拟确定盾构隧道施工的影响范围,完成建设现状评价指标分级量化;分别采用层次分析法和熵权法计算评价指标主观和客观权重,通过博弈论确定组合权重。在此基础上,利用综合指数法对杭州市文一路地下空间开发适宜性进行评价。通过评价结果对比分析和学院路地下工程实例,验证了评价模型的可靠性,为地下空间开发规划提供指导和借鉴。

关键词：地下空间适宜性组合权重数值模拟杭州市

FAM72基因家族与肝细胞癌预后及免疫浸润的相关性分析

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岭南现代临床外科 2024年第1期24卷 14-25页

作者：林坤鹏巴明臣唐云强王嘉康林晓纯广州医科大学附属肿瘤医院肝胆外科广州510095 广州市第一人民医院体检中心广州510180

目的探讨FAM72基因家族在肝细胞癌(HCC)中的表达情况及其与预后、免疫浸润的相关性。方法应用TCGA分析FAM72基因家族在HCC中的表达情况、与不同临床特征间的差异及其预后价值;TCGA和Kaplan⁃Meier plotter分析FAM72基因家族对HCC患者总... 详细信息

目的探讨FAM72基因家族在肝细胞癌(HCC)中的表达情况及其与预后、免疫浸润的相关性。方法应用TCGA分析FAM72基因家族在HCC中的表达情况、与不同临床特征间的差异及其预后价值;TCGA和Kaplan⁃Meier plotter分析FAM72基因家族对HCC患者总生存期的影响;STRING构建FAM72基因家族蛋白相互作用网络;ssGSEA分析FAM72基因家族与免疫浸润细胞间的相关性;GEPIA分析FAM72基因家族与免疫细胞分子标志物及免疫检查点的相关性。结果HCC中FAM72⁃D的表达量显著高于正常肝组织(P<0.05)。FAM72A⁃D高表达组患者总生存率显著低于低表达组(P<0.05)。单因素/多因素回归分析和ROC曲线提示FAM72A⁃D可以作为影响HCC患者预后的独立危险因素(P<0.05)。蛋白互作网络分析结果提示FAM72A⁃D与多种蛋白一起参与HCC的发生发展。免疫浸润分析结果显示FAM72A⁃D表达水平与多数免疫细胞浸润水平及免疫细胞分子标志物有关,且与免疫检查点(PD⁃1、PD⁃L1、CTLA⁃4)有正相关关系。结论FAM72基因家族在HCC组织中高表达,并与免疫浸润、不良预后相关,可作为HCC预后的预测指标。

关键词：肝细胞癌 FAM72基因家族预后免疫浸润生物信息学分析

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文冠果种子发育基因表达分析内参基因的选择

林业科学研究 2024年第3期37卷 79-85页

作者：李麟坤梁重钧宁楚龙张薇姜国维张鑫王利兵中国林业科学研究院林业研究所北京100091 西北农林科技大学林学院陕西杨凌712199

[目的]验证ACT基因是否适用于文冠果种子发育的相关基因表达分析,并筛选出在文冠果基因表达分析中最稳定的内参基因。[方法]本研究采用了4种数学算法(ΔCT、BestKeeper、NormFinder、geNorm)评估12个候选内参基因的表达稳定性,并利用在... 详细信息

[目的]验证ACT基因是否适用于文冠果种子发育的相关基因表达分析,并筛选出在文冠果基因表达分析中最稳定的内参基因。[方法]本研究采用了4种数学算法(ΔCT、BestKeeper、NormFinder、geNorm)评估12个候选内参基因的表达稳定性,并利用在线工具RefFinder综合评价。[结果]在文冠果不同发育时期种子内参基因综合评分排名为PP2A>Tip41> EF-1α>18r>UCE>β-TUB>UBQ>α-TUB>CYP>SAM>ACT>GADPH;在文冠果不同组织内参基因综合评分排名为PP2A>Tip41>CYP>18r>UBQ>SAM>EF-1α>UCE>GADPH>α-TUB>ACT>β-TUB。[结论] PP2A和Tip41基因是文冠果基因表达分析最稳定的内参基因。

关键词：文冠果内参基因基因表达种子发育

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Calculation of Apparent Activation Energy of Coal Oxidation at Low Temperatures by Measuring CO Yield

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Journal of China University of Mining and Technology 2006年第1期16卷 37-41页

作者： QI Feng LI Zeng-hua PAN Shang-kun ZHANG lin School of Mining and Safety Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

By analyzing previous studies on activation energy of coal oxidation at low temperatures, a theoretical calculation model of apparent activation energy is established. Yield of CO is measured by using the characteristic detector of coal oxidation at 30-90 ℃. The impact of parameters, such as airflow and particle size, on activation energies is analyzed. Finally, agreement was obtained between activation energies and the dynamic oxygen absorbed in order to test the accuracy of the model. The results show that： 1） a positive exponential relation between concentration of CO and temperature in the process of the experiment is obtained： increases are almost identical and the initial CO is low; 2） the apparent activation energies increase gradually with the sizes of particle at the same airflow, but the gradients increase at a decreasing rate; 3） the apparent activation energies increase linearly with airflow. For the five coal particles, the differences among the energies are relatively high when the airflow was low, but the differences were low when the airflow was high; 4） the optimum sizes of particle, 0.125-0.25 ram, and the optimum volume of airflow, 100 mL/min, are determined from the model; 5） the apparent activation energies decrease with an increase in oxygen absorbed. A negative exponential relation between the two is obtained,

关键词： coal oxidation at low temperature apparent activation energy particle size airflow