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Nano-Micro Letters 2024年第2期16卷 423-437页

作者： Lin Tang Kunpeng Ruan xi Liu Yusheng Tang Yali Zhang Junwei Gu Chongqing Key Laboratory of Green Synthesis and Applications College of ChemistryChongqing Normal UniversityChongqing 401331People’s Republic of China Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072People’s Republic of China

With the rapid development of 5G information technology,thermal conductivity/dissipation problems of highly integrated electronic devices and electrical equipment are becoming *** this work,“high-temperature solid-phase&diazonium salt decomposition”method is carried out to prepare benzidine-functionalized boron nitride(m-BN).Subsequently,m-BN/poly(pphenylene benzobisoxazole)nanofiber(PNF)nanocomposite paper with nacremimetic layered structures is prepared via sol–gel film transformation *** obtained m-BN/PNF nanocomposite paper with 50 wt%m-BN presents excellent thermal conductivity,incredible electrical insulation,outstanding mechanical properties and thermal stability,due to the construction of extensive hydrogen bonds andπ–πinteractions between m-BN and PNF,and stable nacre-mimetic layered ***λ∥andλ_(⊥)are 9.68 and 0.84 W m^(-1)K^(-1),and the volume resistivity and breakdown strength are as high as 2.3×10^(15)Ωcm and 324.2 kV mm^(-1),***,it also presents extremely high tensile strength of 193.6 MPa and thermal decomposition temperature of 640°C,showing a broad application prospect in high-end thermal management fields such as electronic devices and electrical equipment.

关键词： Poly(p-phenylene-2,6-benzobisoxazole)nanofiber Boron nitride Thermal conductivity Electrical insulation

Enhancing competency of clinical research nurses:A comprehensive training and evaluation framework

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World Journal of Clinical Cases 2024年第7期12卷 1378-1381页

作者： Yang-xi Liu Yi Xu Tumor Interventional Department Taizhou Municipal HospitalTaizhou 318099Zhejiang ProvinceChina

The Sun et al's training program for clinical research nurses(CRNs)in the World Journal of Clinical Cases is a comprehensive and scientific *** includes structured frameworks for CRN training,aiming to improve CRN *** program emphasizes practical abilities,updates training content,and improves evaluation *** cultivation of CRN talents focuses on enhancing the training system,establishing a multifaceted evaluation framework,and continuously refining the training *** feedback and evalua-tion are essential to improve CRNs'competency in practical settings.

关键词： Clinical research nurse Framework Nurse Operations Practice Structure

Recent Advances in Cobalt-Catalyzed Regio-or Stereoselective Hydrofunctionalization of Alkenes and Alkynes

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CCS Chemistry 2024年第5期6卷 1130-1156页

作者： Yan Li xi Lu Yao Fu Hefei National Research Center for Physical Sciences at the Microscale CAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyUniversity of Science and Technology of ChinaHefei 230026 Key Laboratory of Precision and Intelligent Chemistry Department of Applied ChemistrySchool of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026

Hydrofunctionalization of alkenes and alkynes is increasingly important in preparing and modifying carbon-centered organic molecules such as pharmaceuticals,agrochemicals,andmaterial *** development of transition-metal-catalysts has revolutionized the hydrofunctionalization of unsaturated hydrocarbons,greatly improving the synthetic efficiency and selectivity of these *** recent years,notable progress has been achieved in low-cost metal-catalyzed alkene and alkyne hydrofunctionalization reactions following the utilization of traditional precious metal catalysts,including palladium,platinum,and ***-abundant cobalt catalysts,which are low in toxicity and exhibit unique reactivity and selectivity,are widely implemented in academic and industrial *** this review,we highlight recent examples of cobalt-catalyzed hydrofunctionalization of alkenes and alkynes to provide an overview of hydrofunctionalization methods,particularly hydroalkylation *** reactions greatly expand the scope and utility of cobalt-catalyzed couplings of carbon—carbon *** also highlight the mechanistic considerations and selective determinants *** hope our discussion will be informative for future developments in cobalt catalysis and hydrofunctionalization reactions.

关键词： hydrofunctionalization cobalt-catalysis alkene alkyne regioselectivity stereoselectivity

Fault Identification for Shear-Type Structures Using Low-Frequency Vibration Modes

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Computer Modeling in Engineering & Sciences 2024年第3期138卷 2769-2791页

作者： Cuihong Li Qiuwei Yang xi Peng School of Civil Engineering Shaoxing UniversityShaoxing312000China School of Civil and Transportation Engineering Ningbo University of TechnologyNingbo315211China Engineering Research Center of Industrial Construction in Civil Engineering of Zhejiang Ningbo University of TechnologyNingbo315211China

Shear-type structures are common structural forms in industrial and civil buildings,such as concrete and steel frame *** diagnosis of shear-type structures is an important topic to ensure the normal use of *** main drawback of existing damage assessment methods is that they require accurate structural finite element models for damage ***,for many shear-type structures,it is difficult to obtain accurate *** order to avoid finite elementmodeling,amodel-freemethod for diagnosing shear structure defects is developed in this *** method only needs to measure a few low-order vibration modes of the *** proposed defect diagnosis method is divided into two *** the first stage,the location of defects in the structure is determined based on the difference between the virtual displacements derived from the dynamic flexibility matrices before and after *** the second stage,damage severity is evaluated based on an improved frequency sensitivity *** innovations of this method lie in two *** first innovation is the development of a virtual displacement difference method for determining the location of damage in the shear *** second is to improve the existing frequency sensitivity equation to calculate the damage degree without constructing the finite *** has been verified on a numerical example of a 22-story shear frame structure and an experimental example of a three-story steel shear *** on numerical analysis and experimental data validation,it is shown that this method only needs to use the low-order modes of structural vibration to diagnose the defect location and damage degree,and does not require finite element *** proposed method should be a very simple and practical defect diagnosis technique in engineering practice.

关键词： Fault diagnosis shear steel structure vibration mode dynamic flexibility frequency sensitivity

Sea-level change in coastal areas of China:Status in 2021

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Advances in Climate Change Research 2024年第3期15卷 515-524页

作者： Wen-Shan LI Hui WANG Wen-xi xiANG Ai-Mei WANG Wei-Qing XU Yu-xi JIANG xin-Hui WU Meng-Yuan QUAN National Marine Data and Information Service Tianjin 300171China Ocean University of Chin1 Qingdao 266100China University of Michigan‒Shanghai Jiao Tong University Joint Institute Shanghai 200030China

The sea level in coastal areas of China reached the second highest in 2021,just after that recorded in *** force and dynamic analyses based on tide gauges,satellite observations,reanalysis data and regional numerical outputs were conducted to understand these abnormally high sea levels and determine their possible *** show that the coastal sea level of China had increased at an annual rate of 3.4±0.3 mm during 1980-2021,with an acceleration of 0.06±0.02 mm per *** superposition of significant oscillations of quasi-2,3-7,quasi-9,quasi-11,quasi-19 and 20-30 years contributed to the anomalously high sea *** negative-phased El Nino/Southern Oscillation was correlated with the anomalously high sea level and the north-south anti-phase pattern of the coastal sea level in ***,phase lags of 1-4 months occurred with the sea-level *** a decadal timescale,the Pacific Decadal Oscillation(PDO)was negatively correlated with the anomalous mean sea level(MSL),and the negative-phased PDO contributed to the anomalous sea-level change in ***,the monthly MSL peaked in April and July,and the contribution of wind stress to the anomalously high sea level was 38.5%in the south of the Taiwan Strait in April and 30%along the coast of China in *** results were consistent with the tide gauge and satellite *** agreement was also observed between the coastal sea-level fingerprint and the air and sea surface temperatures.

关键词： Sealevel La Nina PDO Wind stress

Structural Characterization of Chloroplast Genome in Alpinia japonica(Thunb.)Miq.,a Medicinal Plant of the Genus Alpinia

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Phyton-International Journal of Experimental Botany 2024年第8期93卷 1897-1911页

作者： Wentao Sheng xi Lei xinjie Chen Quan Kuang Department of Biological Technology Nanchang Normal UniversityNanchang330032China

The analysis of chloroplast gene characteristics in Alpinia japonica(Thunb.)*** of great significance for developing relevant genetic *** high-throughput sequencing and bioinformatic research were performed to analyze the chloroplast genome characteristics of *** total chloroplast genome length of *** was 161,906 bp,with a typical circular tetrameric *** 133 genes were annotated,comprising 87 protein-coding,38 tRNA,and 8 rRNA ***,22 genes contained two copies,and 18 genes owned *** sequence analysis showed that it contains 321 simple sequence repeats(SSRs)and 37 long segment *** with the chloroplast genomes of eight representative plants in the genus Alpinia,the gene structure,type,and quantity were relatively ***12 was the highest variation site in the entire chloroplast gene.A phylogenetic tree showed that the genus Alpinia was the most closely related to the genus ***,*** is the most closely related to Alpinia chinensis belonging to the genus ***,the chloroplast genome of a new species was reported in the genus Alpinia,and a basis was provided for the utilization of Alpinia plants as a medical resource.

关键词： The genus Alpinia Alpinia japonica(Thunb.)Miq. chloroplast genome phylogenetic tree

Syntheses and properties of associative acrylamide copolymers containing short hydrophobic chains used in a friction reducer for slick-water fracturing

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Petroleum Science 2024年第3期21卷 1889-1901页

作者： Ya-xing Dai xian-Li Zhang Si-Yuan Liu Feng-Run-Ze Zhang Yi-xi Zhang Yu-Tong Sang Jing-xi Zheng Zhao-Sheng Liu Peng Zhang College of Chemistry and Chemical Engineering Chongqing University of Science and TechnologyChongqing401331China College of Ecology and Environment Chongqing Resources and Environmental Protection of UniversityChongqing401331China China China Property Project Department of Dezhou Mining Property Service CenterShengli Oilfield Company of SinopecDezhou253000ShandongChina

Two allyldimethylalkyl quaternary ammonium salt(AQAS)monomers,N,N-dimethylallylphenylpropylammonium bromide(AQAS1)and N,N-dimethylallylnonylammonium bromide(AQAS2),were synthesized and used to prepare modified polyacrylamide *** new drag reducers were synthesized from acrylamide(AM),sodium acrylate(Na AA)and a cationic modified monomer(AQAS1 or AQAS2)via aqueous solution polymerization,and the copolymers were named P(AM/Na AA/AQAS1)and P(AM/Na AA/AQAS2),*** structures of the drag reduction agents were confirmed by IR and1H NMR *** molecular weight(Mw)of P(AM/Na AA/AQAS1)was 1.79×10^(6)g/*** the copolymer concentration was 1000 mg/L and the flow rate was 45 L/min,in fresh water the highest drag reduction rate was 75.8%,in 10,000 mg/L Na Cl solution the drag reduction rate decreased to 72.9%.The molecular weight of P(AM/Na AA/AQAS2)was 3.17×10^(6)g/*** the copolymer concentration was500 mg/L and the flow rate was 45 L/min,the drag reduction rate reached 75.2%,and in 10,000 mg/L Na Cl solution the drag reduction rate was 73.3%,decreased by approximately 1.9%.The drag reduction rate for partially hydrolyzed polyacrylamide(HPAM)was also investigated,and the results showed that the drag reduction rates for 500 and 1000 mg/L HPAM solutions were merely 43.2%and 49.0%in brine,*** with HPAM,both of the above copolymers presented better drag reduction capacities.

关键词： Shale gas Slick water Drag reducer Modified monomer Copolymerization

Decarboxylative cyanation and thiocyanation via catalytic electron donor-acceptor complex with copper catalysis

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Science China Chemistry 2024年第9期67卷 3019-3028页

作者： Hongping Zhao xiaoxiang xi Tianbao Wu Zimin Chen Minyan Wang Weiming Yuan Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Bioinorganic Chemistry and Materia MedicaSchool of Chemistry and Chemical EngineeringHuazhong University of Science and Technology(HUST)Wuhan 430074China State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093China Shenzhen Huazhong University of Science and Technology Research Institute Shenzhen 518000China

A new catalytic decarboxylative cyanation and thiocyanation via a synergistic Na I/Cu catalysis is *** photoexcited electron donor-acceptor complex by assembly of Na I,R3P,and N-acyloxy-phthalimide ester(NHPI ester)triggers the generation of alkyl radical species,which then engages in Cu-catalyzed radical coupling *** to success of this dual catalytic transformation is the reliable charge transfer between I·and Cu(I).This dual catalytic platform can eliminate the use of expensive iridium-based photocatalyst or synthetically elaborate organic dyes.A series of primary,secondary,and tertiary alkyl nitriles and thiocyanates are easily ***,an asymmetric decarboxylative cyanation by applying a chiral Cu catalyst is also developed to afford chiral nitriles in high *** mechanistic details and the origin of the high enantioselectivity are further investigated by the mechanistic experiments and the density functional theory calculations.

关键词： electron donor-acceptor catalysis copper catalysis cyanation thiocyanation asymmetric synthesis

Learning background restoration and local sparse dictionary for infrared small target detection

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Optoelectronics Letters 2024年第7期20卷 437-448页

作者： HE Yue ZHANG Rui xi Chunmei ZHU Hu School of Communications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China12

This paper proposes a method for learning background restoration for infrared small target detection,employing a local sparse dictionary alongside an equalized structural texture *** method is specifically designed for the detection of small infrared targets,accommodating various levels of brightness,spatial size,and *** proposed model intelligently combines global low-rankness and local sparsity to estimate the rank of the background tensor,leveraging spatial and structural information to overcome the limitations posed by insufficient detailed texture ***,a structural texture representation,combining local gradient maps and local intensity maps,is applied to emphasize small *** comparing our method with nine advanced and representative approaches and quantifying the comparison using various metrics,the experimental results indicate that our proposed method has achieved favorable outcomes in both quantitative assessments and visual results.

关键词： local structural overcome

Metal±organic cage as fluorescent probe for LiPF6 in lithium batteries

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Green Energy & Environment 2024年第10期9卷 1592-1600页

作者： xi Li Dehua Xu Aoxuan Wang Chengxin Peng xingjiang Liu Jiayan Luo Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin University School of Materials Science and Engineering University of Shanghai Science and Technology State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong University

Lithium hexafluorophosphate （LiPF6）,the most commonly used lithium battery electrolyte salt,is vulnerable to heat and *** and qualitative determination the variation of Li PF6have always relied on advanced ***,we develop a fast,convenient,high-selective fluorescence detection method based on metal±organic cages （MOC）,whose emission is enhanced by nearly 20 times in the presence of Li PF6with good stability and photobleaching *** fluorescent probe can also detect moisture in battery *** propose and verify that the luminescence enhancement is due to the presence of hydrogen bond-induced enhanced emission effect in *** excitation-emission matrix spectra and variable-temperature nuclear magnetic resonance spectroscopy are employed to clarify the role of hydrogen bonds in guest-loaded *** functional theory （DFT） calculation is applied to simulate the structure of host-guest complexes and estimate the adsorption energy involved in the *** precisely matched lock-and-key model paves a new way for designing and fabricating novel host structures,enabling specific recognition of other target compounds.

关键词： Metal-organic cage Selective fluorescence probe Moisture detection Hydrogen bond Host-guest complex