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A NEW REARRANGED ABIETANE DITERPENOID FROM CARYOPTERIS INCANA(THUNB)MIQ

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Chinese Chemical Letters 1996年第7期7卷 621-622页

作者： gao, jj Han, GQ Yan, JF Wu, Y BEIJING MED UNIV NATL LAB NAT & BIOMIMET DRUGSBEIJING 100083PEOPLES R CHINA RES INST CHEM DEF ANALYT CHEM LABBEIJING 100083PEOPLES R CHINA LANZHOU UNIV STATE KEY LAB APPL ORGAN CHEMLANZHOU 730000PEOPLES R CHINA

A new rearranged abietane diterpenoid, incanone was isolated from the whole plant of Caryopteris incana (Thunb.) Miq. On the basis of HRMS, EIMS, (1)HNMR, (13)CNMR, DEPT, H-1-H-1 COSY, HMQC, HMBC and NOESY, incanone w...

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Strain-promoted S-arylation and alkenylation of sulfinamides using arynes and cyclic alkynes

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Science China Chemistry 2024年第3期67卷 928-935页

作者： Xi Zou Boming Shen gao-lin Li Qian Liang Yanhua Ouyang Binghe Yang Peiyuan Yu Bing gao State Key Laboratory of Chemo/Bio-Sensing and Chemometrics College of Chemistry and Chemical EngineeringInstitute of Chemical Biology and NanomedicineHunan UniversityChangsha 410082China Department of Chemistry and Shenzhen Grubbs Institute Guangdong Provincial Key Laboratory of CatalysisSouthern University of Science and TechnologyShenzhen 518055China

The conversion of commercially available chiral sulfinamides into pharmaceutically useful chiral sulfoximines via direct SIVfunctionalization is synthetically attractive but challenging due to the competitive reaction of N-functionalization. Herein, we disclose a novel strain-release strategy to access stereospecific and chemoselective SIV-arylation and alkenylation of sulfinamides using arynes and strained cyclic alkynes. This method tolerates an unprecedented chemical diversity of functional groups attached to the nitrogen center(N-R). The origin of the high SIV-selectivity is elucidated by density functional theory calculations, suggesting a stepwise mechanism for the aryne substrates and a concerted mechanism for the cyclic alkynes.

关键词： arylation alkenylation sulfoximines sulfinamides arynes

Chemical Approaches to Emerging Advancements in Deformable Bioelectronics:Synthesis,Device Concepts,Performance,and Applications

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CCS Chemistry 2024年第1期6卷 11-26页

作者： jj Abu-Halimah Aman Majmudar Bozhi Tian Department of Chemistry University of ChicagoChicagoIllinois 60637 The James Franck Institute University of ChicagoChicagoIllinois 60637 The Institute for Biophysical Dynamics University of ChicagoChicagoIllinois 60637

This mini review examines the current advances and future prospects of chemical approaches in deformable bioelectronics,emphasizing their transformative potential in healthcare and other *** mini review outlines novel fabrication strategies that rely on chemical principles to create adaptable,comfortable,and durable bioelectronic devices that are capable of seamlessly integrating into the dynamic biological *** discussion also extends to the integration of innovative device concepts that enhance the outcomes in both sensing and modulation ***-enhancing strategies that use chemistry to refine the sensitivity and precision of these devices are also ***,the mini review explores the emerging applications of chemically enhanced bioelectronic devices in healthcare,reflecting the potential of this field to revolutionize patient care and improve health *** the outlook section,this mini review investigates the promising future of transient and living bioelectronics,emphasizing the pivotal role of chemical approaches in their *** additionally covers the potential of chemical techniques in powering bioelectronic devices using biological systems and discusses the prospective applications of chemically synthesized bioelectronic devices outside of *** the field has made substantial progress,this mini review also identifies challenges that must be addressed,thus underlining the necessity for continued research and chemical innovation in bioelectronics.

关键词： deformable bioelectronics hydrogels biointerfaces sensing modulation semiconductors cells and tissues

Chronic stress as an emerging risk factor for the development and progression of glioma

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Chinese Medical Journal 2024年第4期137卷 394-407页

作者： Lan Yi Xiang Lin Xiaoling She Wei gao Minghua Wu Institute of Cytology and Genetics The Hengyang Key Laboratory of Cellular Stress BiologyHunan Province Cooperative Innovation Center for Molecular Target New Drug StudyHengyang Medical SchoolUniversity of South ChinaHengyangHunan 421001China Department of Pathology The Second Xiangya HospitalCentral South UniversityChangshaHunan 410011China Key Laboratory of Carcinogenesis and Cancer Invasion of Ministry of Education Cancer Research InstituteCentral South UniversityChangshaHunan 410008China NHC Key Laboratory of Carcinogenesis Xiangya HospitalCentral South UniversityChangshaHunan 410008China

Gliomas tend to have a poor prognosis and are the most common primary malignant tumors of the central nervous *** with patients with other cancers,glioma patients often suffer from increased levels of psychological stress,such as anxiety and *** stress(CS)is thought to impact glioma ***,because of the complex mechanisms underlying CS and variability in individual tolerance,the role of CS in glioma remains *** review suggests a new proposal to redivide the stress system into two *** activity is dominant ***-signaling molecules produced by the neuroendocrine system are dominant *** discuss the underlying molecular mechanisms by which CS impacts *** pharmacological treatments are also summarized from the therapeutic perspective of CS.

关键词： Chronic stress Glioma Microbiota-gut-brain axis Neuroendocrine system Stress system Neural circuit

Long Duration Coverage Control of Multiple Robotic Surface Vehicles Under Battery Energy Constraints

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1695-1698页

作者： Shengnan gao Zhouhua Peng Haoliang Wang Lu Liu Dan Wang the School of Electrical and Control Engineering North China University of TechnologyBeijing 100144 the School of Marine Electrical Engineering Dalian Maritime UniversityDalian 116026China State Key Laboratory of Maritime Technology and Safety Dalian 116026 Dalian Key Laboratory of Swarm Control and Electrical Technology for Intelligent Ships Dalian 116026 the School of Marine Engineering Dalian Maritime UniversityDalian 116026

Dear Editor,This letter addresses long duration coverage problem of multiple robotic surface vehicles(RSVs) subject to battery energy constraints,in addition to uncertainties and disturbances. An anti-disturbance energy-aware control method is proposed for performing coverage task of RSVs. Firstly, a centroidal Voronoi tessellation(CVT) is used to optimize the partition of the given coverage area.

关键词： Robotic Battery partition

Seismic safety assessment with non-Gaussian random processes for train-bridge coupled systems

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 241-260页

作者： Zhao Han gao Lei Wei Biao Tan Jincheng Guo Peidong Jiang Lizhong Xiang Ping Key Laboratory of Geomechanics and Embankment Engineering of Ministry of Education Hohai UniversityNanjing 210024China School of Civil Engineering Central South UniversityChangsha 410075China

Extensive high-speed railway(HSR)network resembled the intricate vascular system of the human body,crisscrossing *** events,known for their unpredictability,pose a significant threat to both trains and bridges,given the HSR’s extended operational ***,ensuring the running safety of train-bridge coupled(TBC)system,primarily composed of simply supported beam bridges,is *** methods like the Monte Carlo method fall short in analyzing this intricate system ***,efficient algorithm like the new point estimate method combined with moment expansion approximation(NPEM-MEA)is applied to study random responses of numerical simulation TBC *** of the NPEM-MEA’s feasibility is conducted using the Monte Carlo *** analysis confirms the accuracy and efficiency of the method,with a recommended truncation order of four to six for the ***,the influences of seismic magnitude and epicentral distance are discussed based on the random dynamic responses in the TBC *** methodology not only facilitates seismic safety assessments for TBC systems but also contributes to standard-setting for these systems under earthquake conditions.

关键词： train-bridge coupled(TBC)system random vibration new point estimate method(NPEM) seismic safety assessment moment expansion approximation(MEA) non-Gaussian distributions

Experimental and numerical study of combustion characteristics of ammonia-hydrogen-air swirling flame with/without secondary air injection

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Chinese Journal of Aeronautics 2024年第4期37卷 243-255页

作者： Chunyu LIU Chenhu gao Yue HUANG Hua JIN Dan ZHAO Wenjiang XU Yancheng YOU School of Aerospace Engineering Xiamen UniversityXiamen 361005China School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China Department of Mechanical Engineering University of CanterburyChristchurch 8041New Zealand

Ammonia (NH_(3)) is currently considered to be a potential carbon-free alternative fuel,and its large-scale use as such would certainly decrease greenhouse gas emissions and meet increasingly stringent emission *** the low flame propagation speed and high NO production of NH_(3) hinder its direct application as a renewable fuel,co-combustion of NH_(3)–H_(2)is an effective way to overcome these *** this study,the combustion characteristics of NH_(3)–H_(2)swirling flames under different equivalence ratios and H_2blending ratios conditions are both numerically and experimentally ***,the One-Dimensional (1D) laminar flame computation presents a comparison base and the Three-Dimensional (3D) numerical simulation yields detailed flame property ***,the high-speed camera takes instantaneous swirl flame images and the gas analyzer measures the NO emission at the exit plane of the flame *** and quantitative analysis is performed on the flame structure and NO emission for a series of NH_(3)–H_(2)swirl *** variation trends of the NO emission calculated using different techniques agree very *** quantitative results show that the NO emissions are much higher at lean equivalence ratios than those at rich equivalence ratios,and such difference is closely related to the combustion flame ***,it is shown that the utilization of secondary air injection can achieve a significant reduction in NO emissions at the exit of the combustion chamber at equivalence ratios less than or equal to 0.9.

关键词： Ammonia combustion Swirling flow NO emission characteristics Secondary combustion Chemical reaction mechanism

Performance evaluation of new epoxy resin-based composite phase change materials and their asphalt mixture

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第3期11卷 507-522页

作者： Yuchao gao Jiao Jin Shuai Liu Yinfei Du Guoping Qian Jie Mao Yongqiang Zhu School of Traffic and Transportation Engineering Changsha University of Science and TechnologyChangsha 410114China School of Civil Engineering Central South UniversityChangsha 410075China Guangdong Guanyue Highway and Bridge Co. Ltd.Guangzhou 511452China

In recent years,the temperature-adjusted asphalt pavement has been an extensive concern by scholars in various countries,and this pavement can reduce temperaturerelated *** this study,the shaped composite phase change materials(CPCMs)were successfully synthesized by two processes,which are vacuum impregnation and epoxy ***,the applicability of CPCMs in asphalt mixtures was evaluated by microscopic characterization,chemical compatibility,thermal properties,durability,and leakage ***,CPCMs were applied to the asphalt mixture to evaluate its temperatureadjusted characteristics and pavement ***,the performance of the temperature-adjusted asphalt mixture was analyzed by integrating all *** research shows that the prepared CPCMs have excellent thermal properties and durability,the phase transition temperature is 48.93℃,and the phase transition enthalpy is 106.5 J/g,which fully meets the requirements for use in *** temperature-adjusted asphalt mixture could alleviate the occurrence of extreme temperature,which was 4.9℃lower than the conventional *** pavement performance of the temperatureadjusted asphalt mixture can meet the specified standards for humid *** the factors,the recommended amount of CPCMs is 1.5%.The research results provide a basis for the promotion of temperature-adjusted asphalt pavement and effectively support the development of pavement engineering technology.

关键词： Pavement engineering Temperature-adjusted asphalt mixture Phase change materials Thermal performance

Effects of counter-current driven by electron cyclotron waves on neoclassical tearing mode suppression

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Chinese Physics B 2024年第5期33卷 501-509页

作者：高钦郑平卫 School of Resource Environment and Safety Engineering University of South ChinaHengyang 421001China Demonstration Base for International Science and Technology Cooperation on Nuclear Energy and Nuclear Safety University of South ChinaHengyang 421001China

Through theoretical analysis,we construct a physical model that includes the influence of counter-external driven current opposite to the plasma current direction in the neoclassical tearing mode(NTM).The equation is used with this model to obtain the modified Rutherford equation with co-current and counter-current *** with the reported experimental results,numerical simulations have shown that the localized counter external current can only partially suppress NTM when it is far from the resonant magnetic *** some circumstances,the Ohkawa mechanism dominated current drive(OKCD)by electron cyclotron waves can concurrently create both co-current and *** this instance,the minimal electron cyclotron wave power that suppresses a particular NTM was calculated by the Rutherford *** result is marginally less than when taking co-current alone into *** a result,to suppress NTM using OKCD,one only needs to align the co-current with a greater OKCD peak well with the resonant magnetic *** effect of its lower counter-current does not need to be considered because the location of the counter-current deviates greatly from the resonant magnetic surface.

关键词： driven current neoclassical tearing mode modified Rutherford equation electron cyclotron waves