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Transition-metal-catalyzed remote meta-C-H alkylation and alkynylation of aryl sulfonic acids enabled by an indolyl template

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Chinese Chemical Letters 2024年第8期35卷 254-259页

作者： Pengfei Zhang Qingxue Ma Zhiwei jiang Xiaohua Xu Zhong jin College of Chemistry State Key Laboratory of Elemento-organic ChemistryNankai UniversityTianjin 300071China Key Laboratory of Xinjiang Native Medicinal and Edible Plant Resource Chemistry College of Chemistry and Environmental SciencesKashi UniversityKashgar 844007China

Transition-metal-catalyzed remote sp^(2)C-H functionalization of aryl sulfonic acids was hardly ever real-ized owing to competitive ortho-C-H functionalization of aryl sulfonates and electron-deficient nature of phenyl ***,with the assistance of a practical biaryl indolyl directing template,palladium-catalyzed remote sp^(2)C-H alkylation of aryl sulfonic acids have been achieved in moderate to good yields with exclusive meta ***,remote meta-selective C-H alkynylation of aryl sulfonic acids was also accomplished with a rhodium *** meta-C-H functionalized products proved to be the superior synthetic precursors,which are difficult to access using the conventional strategy.

关键词： C-H functionalization Aryl sulfonic acid Site-selectivity Transition-metal catalysis Alkylation Alkynylation

Improvement of mechanical properties and investigation of strengthening mechanisms on the Ti_(3)AlC_(2) ceramic with nanosized WC addition

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Journal of Advanced Ceramics 2024年第6期13卷 861-876页

作者： Yi Zhong Ying Liu Qinkai jiang Na jin Zifeng Lin jinwen Ye School of Materials Science&Engineering Sichuan UniversityChengdu 610065China Yibin R&D Park Yibin Industrial Technology Research InstituteSichuan UniversityYibin 644005China

Ti_(3)AlC_(2) (TAC) has great potential for use as an ablation material in aerospace applications due to its great oxidation/ablation resistance, but its high-temperature strength and thermal shock resistance still have much room for simultaneous improvement under fast temperature variation conditions. Herein, we used Ti_(3)AlC_(2) and WC powders as raw materials and successfully fabricated textured (Ti,W)_(3)AlC_(2) ceramic with small amounts of TiC and Al_(2)O_(3), and room temperature mechanical properties such as flexural strength (1146±46.9 MPa), fracture toughness (11.78±0.44 MPa·m^(1/2)), and hardness (5.81±0.11 GPa) at 5 wt% WC addition were achieved. The high-temperature strength of the ceramic was significantly improved, and better thermal shock resistance from 298 to 1173 K was simultaneously acquired together with the regulation of the elastic modulus, thermal conductivity, and thermal expansion coefficient, providing (Ti,W)_(3)AlC_(2) with more possibilities for fast-temperature variation applications. Strengthening and toughening mechanisms were proposed. Scanning transmission electron microscopy high-angle annular dark-field imaging (STEM-HADDF) showed that W randomly replaced the Ti1 and Ti2 sites of Ti_(3)AlC_(2), providing a good reference for establishing crystal models, and further density functional theory (DFT) calculations based on these models indicated a higher fracture energy of (Ti,W)_(3)AlC_(2) along different crystal planes, providing superior resistance to transgranular fracture;a lower mismatch degree of (Ti,W)_(3)AlC_(2)/Al_(2)O_(3) resulted in stronger interface bonding, resulting in greater resistance to intergranular fracture as well as more balanced stress distributions at different interfaces.

关键词： mechanical properties solid solution MAX phase transmission electron microscopy(TEM) ceramic atomic structure

The source of Double ITCZ induced by the SST bias over the tropical western Pacific as reflected in CAS-ESM2 Model

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Science China Earth Sciences 2024年第5期67卷 1604-1615页

作者： jinning TONG Fei ZHENG jiangbo jin Ruowen YANG jiang ZHU Qingcun ZENG Department of Atmospheric Sciences Yunnan UniversityKunming 650091China International Center for Climate and Environment Science Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

“Double ITCZ”is a common precipitation bias over the tropical Pacific in current climate models and Earth system models,but the reasons for its formation are still worth exploring and *** this study,we adopted the second version of Chinese Academy of Sciences Earth System Model(CAS-ESM2),by comparing a set of sea surface temperature(SST)bias correction experiments over the tropical Pacific,to explore the possible mechanism of SST bias on inducing the“Double ITCZ”from the perspective of the climatic annual mean bias in the coupled *** revealed that the simulated climatic annual mean SST bias over the tropical Pacific can affect the bias of latent heat flux through the saturation specific humidity,and the bias of latent heat flux can further affect that of vertical velocity of humid air by the condensation release mechanism,and finally modulate the simulated bias in ***,through the inter-comparison between different experiments,it is found that the source of Double ITCZ might mainly come from the annual mean SST bias over the tropical western Pacific through the proposed air-sea coupled process of“SST-saturated specific humidity-latent heat flux-vertical velocity-precipitation”,indicating a possible way on reducing the couple biases in models over the tropical Pacific to improve the accuracy of CAS-ESM2 for climate simulation.

关键词： SST bias Double ITCZ Nudging SST CAS-ESM2

Treatment of acute dacryocystitis by translacrimal canalicular drainage and D-silicone intubation

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International Journal of Ophthalmology(English edition) 2024年第9期17卷 1628-1632页

作者： jin-jing He jing-Wen Gong Jia-Ni Zhou jin jiang Center for Rehabilitation Medicine Department of OphthalmologyZhejiang Provincial People’s Hospital(Affiliated People’s Hospital)Hangzhou Medical CollegeHangzhou 310000Zhejiang ProvinceChina Xianju People’s Hospital Zhejiang Southeast Campus of Zhejiang Provincial People’s HospitalAffiliated Xianju’s HospitalHangzhou Medical CollegeTaizhou 317300Zhejiang ProvinceChina

AIM:To demonstrate the outcomes of translacrimal canalicular drainage using a lacrimal probe and intranasal drainage by D-silicone intubation for acute dacryocystitis(AD).METHODS:This retrospective study included 23 patients with AD and had undergone abscess decompression with the use of lacrimal probe and intranasal drainage by D-silicone intubation between January 2019 and December *** received abscess decompression and systemic antibiotic-corticosteroid from the time of diagnosis.D-silicone tube was inserted within 10d after diagnosis and removed 3-6mo after *** procedure and outcomes of this method were ***:All patients showed improvement of signs and symptoms of AD within *** intraoperative and postoperative complications were *** recurrence of lacrimal sac abscesses occurred after D-silicone tube ***:Lacrimal probe and D-silicone intubation appear to be a feasible,minimally invasive,safe,and effective method,which could be a reasonable choice in the treatment of AD.

关键词： acute dacryocystitis treatment translacrimal canalicular drainage D-silicone intubation

EMD相关度去噪及其在轧机信号处理中的应用

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计量学报 2009年第1期30卷 73-77页

作者：刘彬蒋金水于伟凯燕山大学电气工程学院河北秦皇岛066004

基于经验模式分解（EMD）时间尺度滤波特性，在引入相关度分析的基础上提出了EMD相关度去噪方法。首先对含噪信号进行EMD分解得到信号各个本征模函数（IMF）分量，再根据所建立的相关度阈值函数计算各个分量的相关度值，在与预定阈值比... 详细信息

基于经验模式分解（EMD）时间尺度滤波特性，在引入相关度分析的基础上提出了EMD相关度去噪方法。首先对含噪信号进行EMD分解得到信号各个本征模函数（IMF）分量，再根据所建立的相关度阈值函数计算各个分量的相关度值，在与预定阈值比较得到满足阈值要求的IMF分量，然后对这些分量进行信号重构得到去噪信号。该方法消除了EMD时间尺度滤波不适用于噪声和信号在IMF成分混叠情况下的限制。通过对平稳含噪信号和非平稳含噪信号进行的去噪仿真研究，表明了该方法的有效性。通过轧机在轧钢时实测信号分析验证了该方法的可靠性。

关键词：计量学经验模式分解时间尺度相关度信号去噪信噪比

用于抛掷敏感器的Ka-波段微带集成本振-混频组件(英文)

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红外与毫米波学报 2001年第2期20卷 139-142页

作者：蒋金水李兴国吴文娄国伟南京理工大学毫米波光波近感技术研究所江苏南京210094

介绍一种用于抛掷敏感器的结构紧凑的 Ka-波段微带集成本振 -混频组件 ,给出了该组件的微带电路结构 ,叙述了其中每一部件的功能 .对该组件仔细做了环境和可靠性实验 ,其中包括震动 ,冲击和温度 .在 2 GHz射频带宽内 ,该组件的双边带噪... 详细信息

介绍一种用于抛掷敏感器的结构紧凑的 Ka-波段微带集成本振 -混频组件 ,给出了该组件的微带电路结构 ,叙述了其中每一部件的功能 .对该组件仔细做了环境和可靠性实验 ,其中包括震动 ,冲击和温度 .在 2 GHz射频带宽内 ,该组件的双边带噪声系数是 3.4～ 4.2 d B,在其工作频带内本振到射频的隔离度大于 2 7d B.由于使用了介质谐振器 ,本振的频率稳定度小于 6 0 ppm/℃ .

关键词：双边带噪声系数频率稳定性介质谐振器敏感器抛掷微带电路 Ka-波段微带集成本振-混频组件

Bio-inspired Design and Inverse Kinematics Solution of an Omnidirectional Humanoid Robotic Arm with Geometric and Load Capacity Constraints

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Journal of Bionic Engineering 2024年第2期21卷 778-802页

作者： Zhichao Zhu Zirong Luo Yiming Zhu Tao jiang Minghai Xia Shanjun Chen Boyu jin College of Intelligence Science and Technology National University of Defense TechnologyChangshaChina

Inspired by the driving muscles of the human arm,a 4-Degree of Freedom(DOF)concentrated driving humanoid robotic arm is proposed based on a spatial double parallel four-bar *** four-bar mechanism design reduces the inertia of the elbow-driving unit and the torque by 76.65%and 57.81%,*** the human pose regulation strategy that the human arm picks up a heavy object by adjusting its posture naturally without complicated control,the robotic arm features an integrated position-level closed-form inverse solution method considering both geometric and load capacity *** method consists of a geometric constraint model incorporating the arm angle(φ)and the Global Configuration(GC)to avoid joint limits and singularities,and a load capacity model to constrain the feasible domain of the arm ***,trajectory tracking simulations and experiments are conducted to validate the feasibility of the proposed inverse solution *** simulated maximum output torque,maximum output power and total energy consumption of the robotic arm are reduced by up to 2.0%,13.3%,and 33.3%,*** experimental results demonstrate that the robotic arm can bear heavy loads in a human-like posture,effectively reducing the maximum output torque and energy consumption of the robotic arm by 1.83%and 5.03%,respectively,while avoiding joints beyond geometric and load capacity *** proposed design provides a high payload–weight ratio and an efficient pose control solution for robotic arms,which can potentially broaden the application spectrum of humanoid robots.

关键词： Humanoid robotic arm Bio-inspired design Inverse kinematics solution Load capacity constraint Geometric constraint

Optogenetics in oral and craniofacial research

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第8期25卷 656-671页

作者： Qinmeng ZHANG Luyao SONG Mengdie FU jin HE Guoli YANG Zhiwei jiang Stomatology Hospital School of StomatologyZhejiang University School of MedicineZhejiang Provincial Clinical Research Center for Oral DiseasesKey Laboratory of Oral Biomedical Research of Zhejiang ProvinceCancer Center of Zhejiang UniversityHangzhou 310000China Zhejiang University School of Medicine Hangzhou 310058China

Optogenetics combines optics and genetic engineering to control specific gene expression and biological functions and has the advantages of precise spatiotemporal control,noninvasiveness,and high *** modified photosensory sensors are engineered into proteins to modulate conformational changes with light ***,optogenetic techniques can provide new insights into oral biological processes at different levels,ranging from the subcellular and cellular levels to neural circuits and behavioral ***,we introduce the origins of optogenetics and highlight the recent progress of optogenetic approaches in oral and craniofacial research,focusing on the ability to apply optogenetics to the study of basic scientific neural mechanisms and to establish different oral behavioral test models in vivo(orofacial movement,licking,eating,and drinking),such as channelrhodopsin(ChR),archaerhodopsin(Arch),and halorhodopsin from Natronomonas pharaonis(NpHR).We also review the synergic and antagonistic effects of optogenetics in preclinical studies of trigeminal neuralgia and maxillofacial *** addition,optogenetic tools have been used to control the neurogenic differentiation of dental pulp stem cells in translational *** the scope of optogenetic tools is increasing,there are limited large animal experiments and clinical studies in dental *** future directions include exploring therapeutic strategies for addressing loss of taste in patients with coronavirus disease 2019(COVID-19),studying oral bacterial biofilms,enhancing craniomaxillofacial and periodontal tissue regeneration,and elucidating the possible pathogenesis of dry sockets,xerostomia,and burning mouth syndrome.

关键词： Lasers Cell differentiation Bacterial virulence Nervous system Neurophysiology Behavioral science

On-Chip Micro Temperature Controllers Based on Freestanding Thermoelectric Nano Films for Low-Power Electronics

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Nano-Micro Letters 2024年第7期16卷 98-108页

作者： Qun jin Tianxiao Guo Nicolas Perez Nianjun Yang Xin jiang Kornelius Nielsch Heiko Reith Institute for Metallic Materials Leibniz Institute for Solid State and Materials Research01069 DresdenGermany Institute of Materials Engineering University of Siegen57076 SiegenGermany Institute of Applied Physics Technical University of Dresden01069 DresdenGermany Institute of Materials Science Technical University of Dresden01069 DresdenGermany

Multidimensional integration and multifunctional com-ponent assembly have been greatly explored in recent years to extend Moore’s Law of modern ***,this inevitably exac-erbates the inhomogeneity of temperature distribution in microsystems,making precise temperature control for electronic components extremely ***,we report an on-chip micro temperature controller including a pair of thermoelectric legs with a total area of 50×50μm^(2),which are fabricated from dense and flat freestanding Bi2Te3-based ther-moelectric nano films deposited on a newly developed nano graphene oxide membrane *** tunable equivalent thermal resistance is controlled by electrical currents to achieve energy-efficient temperature control for low-power electronics.A large cooling temperature difference of 44.5 K at 380 K is achieved with a power consumption of only 445μW,resulting in an ultrahigh temperature control capability over 100 K mW^(-1).Moreover,an ultra-fast cooling rate exceeding 2000 K s^(-1) and excellent reliability of up to 1 million cycles are *** proposed on-chip temperature controller is expected to enable further miniaturization and multifunctional integration on a single chip for microelectronics.

关键词： Temperature control Low-power electronics On-chip micro temperature controller Freestanding thermoelectric nano films Temperature-sensitive components