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Spin-orbit torque efficiency enhancement to tungsten-based SOT-MTJs by interface modification with an ultrathin MgO

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Science China(Information Sciences) 2024年第1期67卷 316-317页

作者： Shiyang LU Xiaobai NING Hongchao ZHANG Sixi ZHEN Xiaofei FAN Danrong XIONG dapeng zhu Gefei WANG Hong-Xi LIU Kaihua CAO Weisheng ZHAO Fert Beijing Institute School of Integrated Science and EngineeringBeihang University Truth Memory Corporation

Spin-orbital torque (SOT) based three-terminal magnetic tunnel junctions (MTJs) have attracted much interest as the next generation magnetic random-access memory (MRAM)key device both in the academy and the industry. This is because SOT-MTJs feature high endurance and fast switching speed, benefiting tremendously from the separation of read/write current paths and less incubation time during the write in contrast to the spin-transfer torque (STT) MTJs [1].

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Small tracking error correction for moving targets of intelligent electro-optical detection systems

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Frontiers of Mechanical Engineering 2024年第2期19卷 29-44页

作者： Cheng SHEN Zhijie WEN Wenliang zhu dapeng FAN Mingyuan LING College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China

Small tracking error correction for electro-optical systems is essential to improve the tracking precision of future mechanical and defense technology.Aerial threats,such as“low,slow,and small(LSS)”moving targets,pose increasing challenges to society.The core goal of this work is to address the issues,such as small tracking error correction and aiming control,of electro-optical detection systems by using mechatronics drive modeling,composite velocity–image stability control,and improved interpolation filter design.A tracking controller delay prediction method for moving targets is proposed based on the Euler transformation model of a two-axis,two-gimbal cantilever beam coaxial configuration.Small tracking error formation is analyzed in detail to reveal the scientific mechanism of composite control between the tracking controller’s feedback and the motor’s velocity–stability loop.An improved segmental interpolation filtering algorithm is established by combining line of sight(LOS)position correction and multivariable typical tracking fault diagnosis.Then,a platform with 2 degrees of freedom is used to test the system.An LSS moving target shooting object with a tracking distance of S=100 m,target board area of A=1 m^(2),and target linear velocity of v=5 m/s is simulated.Results show that the optimal method’s distribution probability of the tracking error in a circle with a radius of 1 mrad is 66.7%,and that of the traditional method is 41.6%.Compared with the LOS shooting accuracy of the traditional method,the LOS shooting accuracy of the optimized method is improved by 37.6%.

关键词： electro-optical detection system small tracking error moving target visual servo aiming contro

Total Synthesis of Starfish Cyclic Steroid Glycosides.Part 3,Formal Total Synthesis of Luzonicosides A and D

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Chinese Journal of Chemistry 2023年第8期41卷 903-908页

作者： dapeng zhu Mingyu Geng Dacheng Shen Biao Yu State Key Laboratory of Bioorganic and Natural Products Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai200032 China

Comprehensive Summary Luzonicosides A(1)and D(2)are the major saponins isolated from pacific starfish Echinaster Luzonicus,featuring a sterically congested 16-membered ring which is formed by bridging the C3 and C6 of a 3β,6β-dihydroxy-Δ7-ene steroid with a 1,2-trans-linked linear trisaccharide via glycosidic and ether bonds,respectively.Here,we describe a formal total synthesis of starfish cyclic steroid glycosides 1 and 2.The synthetic route is highly modular and versatile,involving construction of the 16-membered macrocycles via Au(I)-catalyzed intramolecular glycosylation,highly efficient installation of unsaturated sugar moieties with ortho-hexynylbenzoates,elaboration of glucuronic acid unit via post-oxidation,and a de novo synthesis of the ether-linked pyranose unit.

关键词： Cyclic starfish glycosides Gold(l)catalysis Glycosylation De novo synthesis Steroid

Total Synthesis of Starfish Cyclic Steroid Glycosides.Part 2,Model Synthesis via Intramolecular Etherification

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Chinese Journal of Chemistry 2023年第8期41卷 897-902页

作者： Youxi Chen Guozhi Xiao dapeng zhu Biao Yu State Key Laboratory of Bioorganic and Natural Products Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai200032 China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyUniversity of Chinese Academy of SciencesChinese Academy of SciencesKunmingYunnan650201 China

Comprehensive Summary Sepositoside A(1)is a prototypical cyclic steroid glycoside bearing a hybrid 16-membered ring composed of the steroid skeleton and a 1,2-trans-linked trisaccharide.Herein,we report an expedient access toward two simplified analogues,in which the strained 16-membered ring is constructed via Au(I)-catalyzed intramolecular addition of alcohol to epoxide.A similar macroetherification in relevant steroid trisaccharides has been intensively examined,however,failed to furnish the macrocyclic skeleton of Sepositoside A.

关键词： Cyclic starfish glycosides Au(I)catalysis Epoxide Glycosylation Cyclization

Total Synthesis of Starfish Cyclic Steroid Glycosides.Part 1,Synthesis of the Aglycone and Attempts at Installation of the Sugar Units

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Chinese Journal of Chemistry 2023年第8期41卷 891-896页

作者： Bingfeng Shi Youxi Chen Mingyu Geng dapeng zhu Biao Yu State Key Laboratory of Bioorganic and Natural Products Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai200032 China Department of Chemistry Zhejiang UniversityHangzhouZhejiang310027 China

Comprehensive Summary Sepositoside A(1)is the major and first cyclic steroid glycoside isolated from starfishes,which features a strained 16-membered ring formed by tethering C3 and C6 of the steroid aglycone with a linear trisaccharide.We conceived a convergent synthetic plan in which sepositoside A was disconnected into a disaccharide and a steroid-glucose hybrid ether.The desired 3β,6β-dihydroxy-Δ7,8-23-one aglcyone was readily prepared from dehydroepiandrosterone in 12 steps.The etherification of the 6β-hydroxy-Δ7,8-steroid with a variety of hexopyranoside-C6-electrophiles and CO_(2)-extrusion of a steroid-pyranose hybrid carbonate were extensively studied;however,formation of the desired steroid-pyranose etherate linkage has not been successful.Model studies on theβ-selective installation of the(1→2)-linked disaccharide onto the steroidal C3β-OH with the corresponding disaccharideα-imidates were also examined,however,formation of theα-glycosides prevailed.The present results force us to explore alternative approaches to construct the steroid-pyranose etherate linkage and stepwise assembly of the glycans en route to the starfish cyclic steroid glycosides,which will be presented in two articles that follow.

关键词： Cyclic starfish glycosides Etherification Glycosylation Steroid Total synthesis

Microscopic insights into hydrophobicity of cerium oxide:Effects of crystal orientation and lattice constant

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Journal of Materials Science & Technology 2022年第14期109卷 20-29页

作者： dapeng zhu Weiwei Liu Rongzhi Zhao Zhen Shi Xiangyang Tan Zhenhua Zhang Yixing Li Lianze Ji Xuefeng Zhang Key Laboratory for Anisotropy and Texture of Materials(MOE) School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China Institute of Advanced Magnetic Materials College of Materials and Environmental EngineeringHangzhou Dianzi UniversityHangzhou 310012China

Cerium oxide possesses intrinsic hydrophobic properties ascribed to the unique electronic structure.However,the relationship between the crystal structure and hydrophobicity of cerium oxide has not been systematically studied.Herein,it is experimentally and theoretically demonstrated that the water contact angle(105.9°)of the(111)surface is higher than that(91.7°)of the(220)surface,associated with the lower surface free energy(28.44 mN/m)of(111)surface than that(38.48 mN/m)of(220)surface.Furthermore,cerium oxide films with(111)-terminated surface are annealed at 300℃ and 600℃ for1 h,respectively.The lattice constant increases(5.4594Å300℃>the as-deposited),leading to the increased water contact angle(96.7°<96.8°<99.0°).The First-principles calculation provides microscopic insights into the wetting mechanism,originating from the weakened adsorption capacity of the(111)surface for water molecules with the increasing lattice constant.

关键词： Cerium oxide Hydrophobicity Lattice constant Crystal orientation

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运动员过往成绩和个人品德对大学生体育道德判断的影响研究

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武汉体育学院学报 2024年第5期58卷 66-72,88页

作者：祝大鹏周雯武汉体育学院心理学系湖北武汉430079 武汉体育学院运动训练监控湖北省重点实验室湖北武汉430079 武汉学院通识教育课部湖北武汉430212

体育道德判断对个体的体育道德行为具有重要影响。研究使用《体育道德与非体育道德行为判断问卷》调查了909名大学生(男生=520人,女生=389人,平均年龄=19.76±2.92岁)。检验了大学生对体育道德行为和非体育道德行为在道德判断和奖惩判... 详细信息

体育道德判断对个体的体育道德行为具有重要影响。研究使用《体育道德与非体育道德行为判断问卷》调查了909名大学生(男生=520人,女生=389人,平均年龄=19.76±2.92岁)。检验了大学生对体育道德行为和非体育道德行为在道德判断和奖惩判断的差异,以及运动员过往成绩和个人品德对大学生体育道德判断的影响。结果表明,(1)运动员的过往成绩和个人品德对大学生的体育道德判断和奖惩判断产生了显著影响,但在对具体行为的影响性质上存在差异;(2)运动员过往成绩和个人品德在影响大学生体育道德判断过程中存在相互作用,削弱了两者的独立影响效应。在体育教育过程中要发挥道德情绪的积极作用,排除干扰道德判断的影响因素,引导大学生在道德判断中坚持道德原则。

关键词：体育道德判断道德行为过往成绩个人品德

国际运动心理服务发展进程中的挑战与中国镜鉴

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天津体育学院学报 2024年第1期39卷 27-35页

作者：祝大鹏漆昌柱武汉体育学院心理学系湖北武汉430079 武汉体育学院运动训练监控湖北省重点实验室湖北武汉430079 黄冈师范学院湖北黄冈438000

运动心理服务是运动心理学实践应用的重要形式,对国际运动心理服务发展新形势下面临的挑战以及对我国运动心理学服务的应对策略进行分析发现,当前国际运动心理服务在自身方面存在缺乏明确准入标准、从业者心理健康关注不够、从业者文化... 详细信息

运动心理服务是运动心理学实践应用的重要形式,对国际运动心理服务发展新形势下面临的挑战以及对我国运动心理学服务的应对策略进行分析发现,当前国际运动心理服务在自身方面存在缺乏明确准入标准、从业者心理健康关注不够、从业者文化胜任力缺位的挑战;在运动心理服务研究上存在定性研究比例失衡、研究技术更新升级滞后、理论与实践脱节的挑战;在运动心理服务实践上存在对运动员身心健康缺乏足够重视、教练员心理服务能力建设缺失、运动心理服务职业道德评估与监督失位、运动心理学从业者职业反思匮乏等挑战。面对发展进程中的挑战,我国运动心理服务在发展过程中需要着力打造运动心理服务的中国方案、拓展服务领域与范围,扩大社会影响力、加强运动心理服务理论构建,重视循证实践、加强专业人才培养,建立专业培养规范、完善服务模式。全面提升运动心理服务质量,为我国体育事业发展做出积极贡献,为世界运动心理学发展贡献中国力量。

关键词：运动心理学运动心理服务运动员心理健康职业发展

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Synthesis of the Diverse Glycosides in Traditional Chinese Medicine

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Chinese Journal of Chemistry 2018年第8期36卷 681-691页

作者： dapeng zhu Biao Yu State Key Laboratory of Bioorganic and Natural Products Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences345 Lingling Road Shanghai 20032 China

CT Traditional Chinese medicine （TCM） is a huge treasure trove for the discovery and development of modern pharmaceuticals. Indeed, numerous biologically and pharmacologically significant molecules have been identified from TCM; among them, a considerable portion belongs to glycosides. These glycosides are extremely diverse in structures, consisting of a large variety of aglycones, glycans, as well as glycosidic linkages. In addition, these glycosides occur frequently as a complicated mixture of congeners in the nature sources. This micro-heterogeneity leads to the isolation of a ho- mogeneous glycoside in an appreciable amount a formidable task. Therefore, development of synthetic approaches toward these nature glycosides has received great attention. In this account, we summarize our twenty-year efforts spent on this topic. Fifty five representative TCM-relevant glycosides synthesized by our group are highlighted. Based on the aglycone structure, these glycosides are categorized into three groups, i.e., steroid glycosides, triterpene glycosides, and flavonoid and phenolic glycosides. Typical synthetic approaches are discussed, showing the demanding tactics for regio- and stereo-controlled installation of glycans and overall manipulation of protecting groups. These expedient and scalable synthetic approaches have provided practical alternatives to the accessibility of these TCM components and thus opportunities for their in depth biological and pharmacological studies.

关键词： synthesis glycoside traditional Chinese medicine glycosylation saponin flavonoid