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CCS Chemistry 2023年第1期5卷 124-132页

作者： Yu-Jing Cheng liu-peng zhao Lijia Wang Yong Tang State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesUniversity of Chinese Academy of SciencesShanghai 200032 Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development Shanghai Frontiers Science Center of Molecule Intelligent SynthesesSchool of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062

Myrtoidine and malagashanine,highly complex indole alkaloids,are effective adjuvants in developing cures for plasmodium malaria and potent multi-drug resistant agents.Despite nearly 30 years of progress,myrtoidine and the related family of Malagasy alkaloids still present formidable challenges for synthetic chemists.Here,we developed a diastereoselective[2+2+2]tandem cyclization reaction with alkyl-substituted methylene malonate,enabling highly efficient collective total synthesis of four Malagasy alkaloids from commercially available tryptamines within 10-13 steps.The synthetic strategy included rapid and highly stereoselective assembly of the tetracyclic indoline core containing 5-7 contiguous stereogenic carbon centers,rarely seen in indole alkaloids.Among the four natural products,(±)-myrtoidine,(±)-11-demethoxymyrtoidine,and(±)-12-hydroxymalagashanine were synthesized for the first time,and the work on(±)-malagashanine represented the shortest synthetic route so far.Our current study should enable further explorations of chemical and biological spaces based on myrtoidine,malagashanine,and related natural products.

关键词： tandem cyclization [2+2+2] methylene malonate indole alkaloids myrtoidine malagashanine

Highly Stereoselective Direct Construction of Diaryl-Substituted Cyclobutanes

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Chinese Journal of Chemistry 2020年第3期38卷 259-262页

作者： Xiang-Yang Song liu-peng zhao Lijia Wang Yong Tang State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesUniversity of Chinese Academy of Sciences345 Lingling LuShanghai 200032China Shanghai Key Laboratory of Green Chemistry and Chemical Processes Department of ChemistryEast China Normal University3663 North Zhongshan RoadShanghai 200062China

A copper catalyzed stereoselective[2+2]cyclization has been developed,providing a concise protocol to the direct construction of diaryl-substituted cyclobutanes in up to 99%yield with up to>95/5 dr.Meanwhile,the enantioselective version of this reaction has also been achieved,leading to a series of optically active diaryl-substituted cyclobutanes with up to 94%ee.

关键词： substituted butane Highly

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WiFense:从衍射模型到边界监控

软件学报 2024年第3期35卷 1515-1533页

作者：刘兆鹏李晟洁张越曾有为张大庆北京大学信息科学技术学院北京100871 高可信软件技术教育部重点实验室(北京大学) 北京100871

近年来,随着普适计算概念的深入人心,智能感知技术已成为研究者们关注的焦点,且基于WiFi的非接触式感知因其优秀的普适性、低廉的部署成本以及良好的用户体验越来越受到学术界和工业界的青睐.典型的WiFi非接触式感知工作有手势识别、呼... 详细信息

近年来,随着普适计算概念的深入人心,智能感知技术已成为研究者们关注的焦点,且基于WiFi的非接触式感知因其优秀的普适性、低廉的部署成本以及良好的用户体验越来越受到学术界和工业界的青睐.典型的WiFi非接触式感知工作有手势识别、呼吸检测、入侵检测、行为识别等,这些工作若实际部署,需首先避免其他无关区域中无关行为的干扰,因此需要判断目标是否进入到特定的感知区域中.这意味着系统应具备精准判断目标在界线哪一侧的能力,然而现有工作未能找到一个可以对某个自由设定的边界进行精确监控的方法,这阻碍了WiFi感知应用的实际落地.基于这一关键问题,从电磁波衍射的物理本质出发,结合菲涅尔衍射模型(Fresnel diffraction model),找到一种目标穿越link(收发设备天线的连线)时的信号特征(Rayleigh distribution in Fresnel diffraction model,RFD),并揭示该信号特征与人体活动之间的数学关系;之后以link作为边界,结合天线间距带来的波形时延以及AGC(automatic gain control)在link被遮挡时的特征,通过越线检测实现对边界的监控.在此基础上,还实现了两个实际应用,即入侵检测系统和居家状态监测系统,前者的精确率超过89%、召回率超过91%,后者的准确率超过89%.在验证所提边界监控算法的可用性和鲁棒性的同时,也展示了所提方法与其他WiFi感知技术相结合的巨大潜力,为WiFi感知技术的实际部署提供了思考方向.

关键词：非接触式感知 WiFi 信道状态信息(CSI) link穿越检测边界监控

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非共线多裂纹结构的剩余强度分析与评估

机械设计与制造 2024年第5期399卷 229-233页

作者：贾宝惠刘兆鹏卢翔耿亚南中国民航大学航空工程学院天津300300

针对老龄飞机的广布疲劳损伤(Widespread Fatigue Damage,WFD)评估问题,通过试验方法研究了不同结构参数对非共线多裂纹结构剩余强度的影响,修正原有剩余强度评估方法中的缺陷,提出改进的净截面屈服准则和改进的Irwin塑性区连通准则,获... 详细信息

针对老龄飞机的广布疲劳损伤(Widespread Fatigue Damage,WFD)评估问题,通过试验方法研究了不同结构参数对非共线多裂纹结构剩余强度的影响,修正原有剩余强度评估方法中的缺陷,提出改进的净截面屈服准则和改进的Irwin塑性区连通准则,获得更准确的评估结果。改进的净截面屈服准则评估结果误差小,适用范围广,可以评估铆钉孔间距和铆钉孔直径对结构剩余强度的影响;改进的Irwin塑性区连通准则在铆钉孔间距大于10mm时,有较准确的评估结果,还可以评估裂纹分布位置对剩余强度的影响。

关键词：广布疲劳损伤试验分析非共线裂纹剩余强度

Discovery of GluN2A subtype-selective N-methyl-d-aspartate(NMDA)receptor ligands

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Acta Pharmaceutica Sinica B 2024年第5期14卷 1987-2005页

作者： Liyang Jiang Na liu Fabao zhao Boshi Huang Dongwei Kang peng Zhan Xinyong liu Department of Medicinal Chemistry Key Laboratory of Chemical Biology(Ministry of Education)School of Pharmaceutical SciencesCheeloo College of MedicineShandong UniversityJinan 250012China

The N-methyl-d-aspartate(NMDA)receptors,which belong to the ionotropic Glutamate receptors,constitute a family of ligand-gated ion channels.Within the various subtypes of NMDA receptors,the GluN1/2A subtype plays a significant role in central nervous system(CNS)disorders.The present article aims to provide a comprehensive review of ligands targeting GluN2A-containing NMDA receptors,encompassing negative allosteric modulators(NAMs),positive allosteric modulators(PAMs)and competitive antagonists.Moreover,the ligands’structure–activity relationships(SARs)and the binding models of representative ligands are also discussed,providing valuable insights for the clinical rational design of effective drugs targeting CNS diseases.

关键词： NMDA receptors GluN2A subtype Subtype-selective ligands SARs Protein ligand interactions

Local saliency consistency-based label inference for weakly supervised salient object detection using scribble annotations

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CAAI Transactions on Intelligence Technology 2024年第1期9卷 239-249页

作者： Shuo zhao peng Cui Jing Shen Haibo liu School of Computer Science and Technology Harbin University of Science and TechnologyHarbinChina School of Computer Science and Technology Harbin Engineering UniversityHarbinChina

Recently,weak supervision has received growing attention in the field of salient object detection due to the convenience of labelling.However,there is a large performance gap between weakly supervised and fully supervised salient object detectors because the scribble annotation can only provide very limited foreground/background information.Therefore,an intuitive idea is to infer annotations that cover more complete object and background regions for training.To this end,a label inference strategy is proposed based on the assumption that pixels with similar colours and close positions should have consistent labels.Specifically,k-means clustering algorithm was first performed on both colours and coordinates of original annotations,and then assigned the same labels to points having similar colours with colour cluster centres and near coordinate cluster centres.Next,the same annotations for pixels with similar colours within each kernel neighbourhood was set further.Extensive experiments on six benchmarks demonstrate that our method can significantly improve the performance and achieve the state-of-the-art results.

关键词： label inference salient object detection weak supervision

Tuning interface mechanism of FeCo alloy embedded N,S-codoped carbon substrate for rechargeable Zn-air battery

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Journal of Energy Chemistry 2024年第6期93卷 400-410,I0010页

作者： Hui Chang Lulu zhao Shan zhao Zong-Lin liu peng-Fei Wang Ying Xie Ting-Feng Yi School of Materials Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina Key Laboratory of Functional Inorganic Material Chemistry Ministry of EducationSchool of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080HeilongjiangChina Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province School of Resources and MaterialsNortheastern University at QinhuangdaoQinhuangdao 066004HebeiChina

The interface mechanism between catalyst and carbon substrate has been the focus of research.In this paper,the FeCo alloy embedded N,S co-doped carbon substrate bifunctional catalyst(FeCo/S-NC)is obtained by a simple one-step pyrolysis strategy.The experimental results and density functional theory(DFT)calculation show that the formation of FeCo alloy is conducive to promoting electron transfer,and the introduction of S atom can enhance the interaction between FeCo alloy and carbon substrate,thus inhibiting the migration and agglomeration of particles on the surface of carbon material.The FeCo/SNC catalysts show outstanding performance for oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).FeCo/S-NC shows a high half-wave potential(E_(1/2)=0.8823 V)for ORR and a low overpotential at 10 mA cm^(-2)(E_(j=10)=299 mV)for OER.In addition,compared with Pt/C+RuO_(2) assembled Zn-air battery(ZAB),the FeCo/S-NC assembled ZAB exhibits a larger power density(198.8 mW cm^(-2)),a higher specific capacity(786.1 mA h g_(zn)~(-1)),and ultra-stable cycle performance.These results confirm that the optimized composition and the interfacial interaction between catalyst and carbon substrate synergistically enhance the electrochemical performance.

关键词： FeCo alloy N S co-doped carbon DFT calculation Zn-air batteries Interfacial interaction

Cation-Dipole Interaction-Induced Coacervate Underwater Adhesives in Natural Seawater

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Chinese Journal of Polymer Science 2024年第7期42卷 984-991,I0009页

作者： Xu-Fei liu Chong-Rui Zhang Hua-Wen peng Qiang zhao Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan430074China

Significant progress has been made in wet adhesives for low salinity water,but exploration of general ionic adhesives for natural seawater is less developed because the high salinity could weaken interfacial bonding and shields electrostatic interactions,resulting in adhesion failure.Thus,the design of adhesives for natural seawater represents challenges less resolved.Herein,a cationic polyelectrolyte(PECHIA)containing imidazolacetonitrile unit was explored to prepare adhesives enabled by natural seawater.By combining the ion shielding effect with the“cation-dipole”interactions between PECHIA chains,aqueous solution of the PECHIA underwent coacervation and self-crosslinking in natural seawater,allowing for underwater adhesion to various substrates in seawater.The instantaneous lap-shear and tensile adhesion strengths are 47 and 119 kPa,respectively,while the cured adhesive shows~739 k Pa tensile adhesion in natural seawater.The design of PECHIA enables wet adhesives viable for applications in the diversified scenarios of natural seawater.

关键词： Coacervate Underwater adhesives Seawater Cation-dipole interaction

Identification of Motor Nuclei in the Medulla Oblongata of Carp for Biological Control

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Journal of Bionic Engineering 2024年第2期21卷 842-851页

作者： Yang zhao Yong peng Yudong Wen Lingjun Han Yanhong Yan Xueying Dong Hui Zhang Zheng zhao Xiaoyue liu School of Electrical Engineering Yanshan UniversityQinhuangdao066004China School of Mechanical Engineering Yanshan UniversityQinhuangdao066004China Key Laboratory of National Defense of Mechanical Structure and Material Science Under Extreme Conditions Yanshan UniversityQinhuangdao066004China Institute of Marine Science and Engineering Yanshan UniversityQinhuangdao066004China Shijiazhuang University Shijiazhuang050035China

Brain-controlled technology is the key technology in biological control,and the corresponding relationship between animal brain nuclei and motor behavior is the core.The purpose of this study was to explore the motor nuclei of the medulla oblongata in carp.The carps were subjected to electrical stimulation and chemical stimulation experiments,respectively,in the water-free state,and the effective chemical stimulation sites were injected with the pontamine sky blue solution.The brain tissue sections were obtained by paraffin tissue section technology and the neutral red staining method.By comparing the positions of the brain nuclei shown in earlier studies,the motor nerve nuclei in the medulla oblongata were identified.The brain electrode was implanted into the motor nucleus of the medulla oblongata,and the underwater control experiment and behavioral tests were carried out with different electrical stimulation parameters.The results showed that the abducens nucleus(NVI)was the motor nucleus that controls the ipsilateral steering,and the facial nucleus(NVII)was the motor nucleus that controls the forward movement.By adjusting the stimulation voltage and the stimulation pulse number,the carp can be stably controlled to achieve a left–right steering motion of 30°–180°and a forward motion of more than 80 cm/s.This study indicated that the quantitative control of the steering and forward behavior of the carp can be achieved by electrical stimulation of the NVI and NVII,which provided a certain experimental basis for the accurate control of the carp robot.

关键词： Biological control Carp Medulla oblongata motor nucleus Electrical stimulation technique Chemical stimulation technique

Ultracompact silicon on-chip polarization controller

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Photonics Research 2024年第2期12卷 183-193页

作者： WEIKE zhao YINGYING peng MINGYU ZHU RUORAN liu XIAOLONG HU YAOCHENG SHI DAOXIN DAI State Key Laboratory for Modern Optical Instrumentation Center for Optical&Electromagnetic ResearchCollege of Optical Science and EngineeringInternational Research Center for Advanced PhotonicsZhejiang UniversityZijingang CampusHangzhou 310058China School of Precision Instrument and Optoelectronic Engineering Tianjin UniversityTianjin 300072China Key Laboratory of Optoelectronic Information Science and Technology Ministry of EducationTianjin 300072China Ningbo Research Institute Zhejiang UniversityNingbo 315100China

On-chip polarization controllers are extremely important for various optical systems.In this paper,a compact and robust silicon-based on-chip polarization controller is proposed and demonstrated by integrating a special polarization converter and phase shifters.The special polarization converter consists of a 1×1 Mach–Zehnder interferometer with two polarization-dependent mode converters at the input/output ends.When light with an arbitrary state of polarization(SOP)is launched into the chip,the TE_(0)and TM_(0)modes are simultaneously excited.The polarization extinction ratio(PER)and the phase difference for the TE_(0)∕TM_(0)modes are tuned by controlling the first phase shifter,the polarization converter,and the second phase shifter.As a result,one can reconstruct the light SOP at the output port.The fabricated polarization controller,as compact as~150μm×700μm,exhibits an excess loss of less than 1 dB and a record PER range of>54 dB for arbitrary input light beams in the wavelength range of 1530–1620 nm.

关键词： polarization SOP interferometer