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Chinese Journal of Chemistry 2024年第17期42卷 1993-1998页

作者： chen Zhou Mengfu Dai Xiaoyu yin Mingyue Zhang Weijin Gu Liang-An chen Jiangsu Collaborative Innovation Center of Biomedical Functional Materials Jiangsu Key Laboratory of New Power BatteriesSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjingJiangsu 210023China

The stereochemical synthesis of highly substituted Danishefsky-type dienes remains unsolved in organic *** describe a simple and efficient approach for the stereoselective synthesis of Danishefsky-type trisubstituted dienes from readily available propargylic esters via Pd-catalyzed dienylation reaction through the key intermediate metallacyclobutene in a regio-,chemo-and stereoselective *** method facilitates a broad range of challenging trisubstituted dienes with a high level of stereocontrol.

关键词： Propargylic ester Dienylation Diene Stereoselectivity Cycloaddition Palladium β-H elimination Regioselectivity

Efficient conversion of acoustic vortex using extremely anisotropic metasurface

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Frontiers of physics 2024年第4期19卷 257-264页

作者： Zhanlei Hao Haojie chen Yuhang yin cheng-Wei Qiu Shan Zhu Huanyang chen Institute of Electromagnetics and Acoustics and Department of Physics College of Physical Science and TechnologyXiamen UniversityXiamen 361005China Department of Electrical and Computer Engineering National University of Singapore4 Engineering Drive 3117583Singapore Department of Mechanical and Electrical Engineering Xiamen UniversityXiamen 361005China Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen 361005China

Vortex wave and plane wave,as two most fundamental forms of wave propagation,are widely applied in various research ***,there is currently a lack of basic mechanism to enable arbitrary conversion between *** this paper,we propose a new paradigm of extremely anisotropic acoustic metasurface(AM)to achieve the efficient conversion from 2D vortex waves with arbitrary orbital angular momentum(OAM)to plane *** underlying physics of this conversion process is ensured by the symmetry shift of AM medium parameters and the directional compensation of ***,this novel phenomenon is further verified by analytical calculations,numerical demonstrations,and acoustic experiments,and the deflection angle and direction of the converted plane waves are qualitatively and quantitatively confirmed by a simple *** work provides new possibilities for arbitrary manipulation of acoustic vortex,and holds potential applications in acoustic communication and OAM-based devices.

关键词： efficient wave conversion vortex wave plane wave orbital angular momentum acoustic metasurface

Effective dynamics for a spin-1/2 particle constrained to a curved layer with inhomogeneous thickness

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Chinese Physics B 2024年第2期33卷 78-83页

作者：梁国华尹佩林 School of Science Nanjing University of Posts and TelecommunicationsNanjing 210023China

We derive an effective Hamiltonian for a spin-1/2 particle confined within a curved thin layer with non-uniform thickness using the confining potential *** analysis reveals the presence of a pseudo-magnetic field and effective spin–orbit interaction(SOI)arising from the curvature,as well as an effective scalar potential resulting from variations in ***,we demonstrate that the physical effect of additional SOI from thickness fluctuations vanishes in low-dimensional systems,thus guaranteeing the robustness of spin interference measurements to thickness ***,we establish the applicability of the effective Hamiltonian in both symmetric and asymmetric confinement scenarios,which is crucial for its utilization in one-side etching systems.

关键词： curved surface inhomogeneous thickness spin-1/2 particle effective Hamiltonian

Total suprarenal aortic occlusion with cardiac disease: a case series of three cases

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World Journal of Emergency Medicine 2024年第1期15卷 59-61页

作者： Yuanli Lei Jiaozhen chen Qin chen Jiana yin Weijia Huang Wenxing Song Shouquan chen Department of Emergency Medicine the First Affi liated Hospital of Wenzhou Medical UniversityWenzhou 325000China Department of Electrocardiogram Wenzhou People's HospitalWenzhou 325000China

Acute aortic occlusion(AAO)has been very rarely reported in the literature and is a potentially life-threatening emergency.[1-5]AAO mostly occurs in cardiac disease patients,[1-4,6,7]and leads to cardiac complications.[1,2,5,6]Suprarenal aortic occlusion(SAO)is a very rare type of AAO,and infrarenal aortic occlusion(IAO)accounts for 75.8%-97.8%.[1,3,5-7]SAO is different from IAO in some clinical manifestations,treatment strategies,and prognoses.[3,6-8]SAO with cardiac disease will make the condition more complex and could easily cause a delay in diagnosis and portend worse outcomes with amputation and mortality rates.[1,3,6]Early and fast diagnosis and positive revascularization treatment are necessary to prevent cases from becoming fatal.[1-3]Herein,we present a case series of SAO with cardiac disease.

关键词： cardiac occlusion diagnosis

Clinical relevance of distolingual roots and periodontal status in mandibular first molars: a cross-sectional study employing CBCT analysis

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第3期25卷 244-253页

作者： Feifei MAO Meng WANG Shuai ZHOU Yan ZHAO Jiaping HUANG Fengying yin Haiping YANG pei-hui DING 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 310016China

Objectives:Distolingual root of the permanent mandibular first molar(PMFM-DLR)has been frequently reported,which may complicate the treatment of *** study aimed to assess the morphological features of PMFM-DLR and investigate the correlation between the morphological features of PMFM-DLR and periodontal status in patients with Eastern Chinese ethnic *** and methods:A total of 836 cone beam computed tomography(CBCT)images with 1497 mandibular first molars were analyzed to observe the prevalence of PMFM-DLR at the patients and tooth levels in Eastern *** them,complete periodontal charts were available for 69 Chinese patients with 103 *** and regression analyses were used to evaluate the correlation between the morphological features of DLR,bone loss,and periodontal clinical parameters,including clinical attachment loss(CAL),probing pocket depth(PPD),gingival recession(GR),and furcation involvement(FI).Results:The patient-level prevalence and tooth-level prevalence of DLR in mandibular first molars were 29.4%and 26.3%,*** linear regression analysis suggested that bone loss at the lingual site and CAL were negatively affected by the angle of separation between distolingual and mesial roots in the transverse section,while they were significantly influenced by age and the angle of separation between distobuccal and mesial roots in the coronal ***:The prevalence of PMFM-DLR in Eastern China was relatively high in our *** morphological features of DLR were correlated with the periodontal status of mandibular first *** study provides critical information on the morphological features of DLR for improved diagnosis and treatment options of mandibular molars with DLR.

关键词： Distolingual root Mandibular first molar Periodontal clinical parameter Clinical attachment loss Cone beam computed tomography(CBCT)

Arbitrary acoustic orbital angular momentum detection using dual-layer metasurfaces

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 106-112页

作者： Zhanlei Hao Haojie chen Yuhang yin Shan Zhu Yadong Xu cheng-Wei Qiu Huanyang chen Department of Physics College of Physical Science and TechnologyXiamen UniversityXiamen 361005China Department of Electrical and Computer Engineering National University of SingaporeSingapore 117583Singapore Department of Mechanical and Electrical Engineering Xiamen UniversityXiamen 361005China Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen 361005China School of Physical Science and Technology and Jiangsu Key Laboratory of Thin Films Soochow UniversitySuzhou 215006China

Orbital angular momentum(OAM),with its unique physical properties and vast application prospects,has attracted widespread attention in various ***,the development of valid and practical acoustic OAM detection methods continues to be a challenging *** this paper,we propose a novel construction method of dual-layer metasurfaces to achieve a doubleconversion process for the waveform reshaping and differentiated focusing of two-dimensional vortex sources with different ***,by utilizing a concise formula,a one-to-one correspondence is established between the OAM of incident vortex waves and different imaging *** fundamental principle of this special conversion relationship is rigorously constrained by the directional compensation of phase and the material parameters of dual-layer metasurfaces with different quadratic phase *** importantly,the highly consistent results between numerical demonstrations and acoustic experiments further confirm the feasibility and effectiveness of the proposed OAM detection *** work provides a new perspective on the precise manipulation for the phase of vortex fields,holding potential applications in super-resolution imaging and the design of acoustic OAM-based devices.

关键词： arbitrary acoustic OAM detection vortex waves dual-layer metasurfaces waveform reshaping differentiated focusing acoustic experiments

Harmonic State Space Based Impedance Modeling and Virtual Impedance Based Stability Enhancement Control for LCC-HVDC Systems

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 287-298页

作者： Yifeng Liu Xiaoping Zhou Quan chen Hanhang yin Lerong Hong Hao Tian ying chen Siyuan Li the College of Electrical and Information Engineering Hunan UniversityChangsha 410082China the Zhejiang Magtron Intelligent Technology Limited Cooperation Jiaxing 314000China the State Grid Qianjiang Electric Power Company Qianjiang 433100China

Line commutated converter based high-voltage direct-current(LCC-HVDC)transmissions are prone to harmonic oscillation under weak *** modeling is an effective method for assessing interaction ***,this paper proposes an improved calculation method for the DC voltage and AC currents of commutation stations to address the complex linearization of the commutation process and constructs an overall harmonic state-space(HSS)model of an *** on the HSS model,the closed-loop AC impedances on the LCC-HVDC sending and receiving ends are then derived and *** impedance characteristics of the LCC-HVDC are then analyzed to provide a physical explanation for the harmonic oscillation of the *** effects of the grid strength and control parameters on system stability are also *** improve the impedance characteristics and operating stability of the LCC-HVDC system,a virtual impedance based stability enhancement control is proposed,and a parameter design method is considered to ensure satisfactory phase margins at both the sending and receiving ***,simulation results are presented to verify the validity of the impedance model and virtual impedance based stability enhancement control.

关键词： Line commutated converter based high-voltage direct-current(LCC-HVDC)transmission harmonic state space stability analysis harmonic oscillation virtual impedance

Torque Limit-based Inertial Control Method Based on Delayed Support for Primary Frequency Control of Wind Turbines

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 561-570页

作者： Wei Gu Zaiyu chen Qun Li Minghui yin Qiang Li Yun Zou School of Automation Nanjing University of Science and TechnologyNanjing 210094China State Grid Jiangsu Electric Power Co. Ltd.Research InstituteNanjing 211103China

To avoid the secondary frequency dip caused by the steep drop of the electrical power of wind turbines(WTs)at the end of frequency support stage,the torque limit-based iner-tial control(TLIC)method sets the power reference as a linear function of rotor speed,rather than the step form for the step-wise inertial ***,the compensation effect on the frequency nadir(FN)caused by the load surge is weakened as the TLIC power is no longer in the step ***,the maximum point of the frequency response component(FRC)contributed by TLIC occurs earlier than the minimum point of FRC corresponding to the load surge,so that the FN cannot be adequately ***,this paper first investigates the relation between the peak and nadir times of FRCs stimulated by the TLIC and load *** this basis,with the compensation principle of matching the peak and nadir times of FRCs,the improved TLIC method based on delayed support is ***,the effectiveness of the proposed method is validated via the experiments on the test bench of wind-integrated power system.

关键词： Wind turbine frequency response component torque limit inertial control delayed support

Transient receptor potential vanilloid 1 involved in the analgesic effects of total flavonoids extracted from Longxuejie(Resina Dracaenae Cochinchinensis)

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Journal of Traditional Chinese Medicine 2024年第3期44卷 437-447页

作者： MO Xiaoqiang chen Yating yin Qian chen Haibo BAN Qiang LI Jun chen Su YAO Jinguang Department of Stomatology Affiliated Hospital of Youjiang Medical University for NationalitiesBaise 533000China College of General Practitioners Youjiang Medical University for NationalitiesBaise 533000China College of Biomedical Engineering South-Central Minzu UniversityKey Laboratory of Cognitive Science of State Ethnic Affairs CommissionHubei Key Laboratory of Medical Information Analysis and Tumor Diagnosis and TreatmentWuhan 430074China College of Pharmacy South-Central Minzu UniversityWuhan 430074China

OBJECTIVE: To evaluate the analgesic effects of total flavonoids of Longxuejie(Resina Dracaenae Cochinchinensis)(TFDB) and explore the possible analgesic mechanism associated with transient receptor potential vanilloid 1(TRPV1).METHODS: Whole-cell patch clamp technique was used to observe the effects of TFDB on capsaicin-induced TRPV1 currents. Rat experiments in vivo were used to observe the analgesic effects of TFDB. Western blot and immunofluorescence experiments were used to test the change of TRPV1 expression in DRG neurons induced by ***: Results showed that TFDB inhibited capsaicin-induced TRPV1 receptor currents in acutely isolated dorsal root ganglion(DRG) neurons of rats and the half inhibitory concentration was(16.7 ± 1.6) mg/***(2-20 mg/kg) showed analgesic activity in the phase Ⅱ of formalin test and(0.02-2 mg per paw)reduced capsaicin-induced licking times of rats. TFDB(20 mg/kg) was fully efficacious on complete Freund's adjuvant(CFA)-induced inflammatory thermal hyperalgesia and capsaicin could weaken the analgesic effects. The level of TRPV1 expressions of DRG neurons was also decreased in TFDB-treated CFA-inflammatory pain ***: All these results indicated that the analgesic effect of TFDB may contribute to their modulations on both function and expression of TRPV1 channels in DRG neurons.

关键词： Freund's adjuvant formaldehyde capsaicin flavonoids Longxuejie(Resina Dracaenae Cochinchinensis) transient receptor potential vanilloid 1 inflammatory pain

Heterogeneous information phase space reconstruction and stability prediction of filling body–surrounding rock combination

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1500-1511页

作者： Dapeng chen Shenghua yin Weiguo Long Rongfu Yan Yufei Zhang Zepeng Yan Leiming Wang Wei chen School of Civil and Resources Engineering University of Science and Technology of BeijingBeijing 100083China Production Technology Department Longshou MineJinchuan Group Co.Ltd.Jinchang 737100China School of Civil Engineering and Architecture East China Jiaotong UniversityNanchang 330013China

Traditional research believes that the filling body can effectively control stress concentration while ignoring the problems of unknown stability and the complex and changeable stress distribution of the filling body–surrounding rock combination under high-stress *** monitoring data processing methods cannot fully consider the complexity of monitoring objects,the diversity of monitoring methods,and the dynamics of monitoring *** solve this problem,this paper proposes a phase space reconstruction and stability prediction method to process heterogeneous information of backfill–surrounding rock *** three-dimensional monitoring system of a large-area filling body–surrounding rock combination in Longshou Mine was constructed by using drilling stress,multipoint displacement meter,and *** information,such as the stress and displacement of the filling body–surrounding rock combination,was continuously *** with the average mutual information method and the false nearest neighbor point method,the phase space of the heterogeneous information of the filling body–surrounding rock combination was then *** this paper,the distance between the phase point and its nearest point was used as the index evaluation distance to evaluate the stability of the filling body–surrounding rock *** evaluated distances(ED)revealed a high sensitivity to the stability of the filling body–surrounding rock *** new method was then applied to calculate the time series of historically ED for 12 measuring points located at Longshou *** moments of mutation in these time series were at least 3 months ahead of the roadway return *** the ED prediction experiments,the autoregressive integrated moving average model showed a higher prediction accuracy than the deep learning models(long short-term memory and Transformer).Furthermore,the root-mean-square error distribution of the prediction results peaked at 0

关键词： deep mining filling body–surrounding rock combination phase space reconstruction multiple time series stability prediction