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Hyperisampsins N and O,two new benzoylated phloroglucinol derivatives from Hypericum sampsonii

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Chinese Chemical Letters 2017年第5期28卷 986-990页

作者： Hu-Cheng Zhu Chun-Mei Chen Jin-Wen Zhang Yi Guo Dong-Dong Tan Guang-Zheng wei Jing Yang Jian-Ping Wang zeng-wei luo Yong-Bo Xue Yong-Hui Zhang Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation School of PharmacyTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Tongji Hospital Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650204China

Twenty-one benzoylated phloroglucinol derivatives bearing homoadamantyl frameworks were isolated from the aerial parts of Hypericum sampsonii,including two new ones named hyperisampsins N and O（1 and 2）.The structures of 1 and 2 were elucidated by extensive NMR and mass spectrometric *** absolute configurations were further determined by using TDDFT ECD *** 2,7,and 8 were evaluated for their cytotoxic activities against five human cancer cell lines,of which,2 and 8 exhibited significant cytotoxic activities toward HL-60 cell and moderate activities against others cell lines.

关键词： Hyperisampsin PPAPs ECD calculation Absolute configuration

Rh(Ⅱ)-catalyzed intermolecular carboamination of pyridines via double Csp^(2)-H bond activations

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Science China Chemistry 2024年第1期67卷 374-382页

作者： Zhongfeng luo Jingxing Jiang Lifang Zou Xiaoyu Zhou Junshan Liu Zhuofeng Ke Fengjuan Chen Huanfeng Jiang wei zeng Key Laboratory of Functional Molecular Engineering of Guangdong Province School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510641China School of Materials Science and Engineering PCFM LabSun Yat-sen UniversityGuangzhou 510275China Guangdong Provincial Key Laboratory of Chinese Medicine Pharmaceutics School of Traditional Chinese MedicineSouthern Medical UniversityGuangzhou 510515China

We disclose the development of the Rh-catalyzed amine-directed remote 5,6-carboamination protocol of pyridines via dual Csp^(2)-H functionalizations.A variety of readily available 2-aminopyridines and 1,2,3-triazoles are allowed for coupling cyclization to access polyfunctionalized *** studies including DFT calculations unveil that relay carbenoidelectrophilic addition to pyridines and the sequential pyridyl Csp^(2)-H amination are involved in this *** postsynthetic utility of this methodology is showcased by versatile and site-selective modification of azaindoles.

关键词： Rh-catalysis azaindoles pyridyl Csp^(2)-H bond carboamination coupling-cyclization

Aboveground biomass stocks of species-rich natural forests in southern China are influenced by stand structural attributes,species richness and precipitation

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Plant Diversity 2024年第4期46卷 530-536页

作者： Wen-Hao zeng Shi-Dan Zhu Ying-Hua luo wei Shi Yong-Qiang Wang Kun-Fang Cao State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources College of ForestryGuangxi UniversityNanning 530004China Guangxi Key Laboratory of Forest Ecology and Conservation College of ForestryGuangxi UniversityNanning 530004China Key Laboratory of National Forestry and Grassland Administration on Biodiversity Conservation in Karst Mountainous Areas of Southwestern China School of Life SciencesGuizhou Normal UniversityHuaxi College TownGui'an DistrictGuiyang 550025China

Forests,the largest terrestrial carbon sinks,play an important role in carbon sequestration and climate change *** forest attributes and environmental factors have been shown to impact aboveground biomass,their influence on biomass stocks in species-rich forests in southern China,a biodiversity hotspot,has rarely been *** this study,we characterized the effects of environmental factors,forest structure,and species diversity on aboveground biomass stocks of 30 plots(1 ha each) in natural forests located within seven nature reserves distributed across subtropical and marginal tropical zones in Guangxi,*** results indicate that forest aboveground biomass stocks in this region are lower than those in mature tropical and subtropical forests in other ***,we found that aboveground biomass was positively correlated with stand age,mean annual precipitation,elevation,structural attributes and species richness,although not with species *** we compared stands with the same basal area,we found that aboveground biomass stock was higher in communities with a higher coefficient of variation of diameter at breast *** findings highlight the importance of maintaining forest structural diversity and species richness to promote aboveground biomass accumulation and reveal the potential impacts of precipitation changes resulting from climate warming on the ecosystem services of subtropical and northern tropical forests in ***,many natural forests in southern China are not fully ***,their continued growth will increase their carbon storage over time.

关键词： Subtropical forest Marginal tropical forest Aboveground biomass Species diversity Forest structural attribute Environment factor

Boosting cycling stability by regulating surface oxygen vacancies of LNMO by rapid calcination

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Nano Research 2024年第4期17卷 2671-2677页

作者： Haoran Jiang Cuihua zeng wei Zhu Jiawei luo Zhedong Liu Jingchao Zhang Rui Liu Yunhua Xu Yanan Chen Wenbin Hu School of Materials Science and Engineering Tianjin UniversityTianjin 300072China School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China

Spinel LiNi_(0.5-x)Mn_(1.5+x)O_(4)(LNMO)has attracted intensive interest for lithium-ion battery due to its high voltage and high energy ***,severe capacity fade attributed to unstable surface structure has hampered its *** vacancies(OVs)tend to occur in the surface of the material and lead to surface structure reconstruction,which deteriorates the battery performance during electrochemical ***,we utilize high-temperature-shock(HTS)method to synthesize LNMO materials with fewer surface *** calcination drives lower surface OVs concentration,reducing the content of Mn^(3+)and surface reconstruction layers,which is beneficial to obtain a stable crystal *** LNMO material synthesized by HTS method delivers an initial capacity of 127 mAh·g^(-1) at 0.1 C and capacity retention of 81.6%after 300 cycles at 1 C,and exhibits excellent performance at low temperature.

关键词： ultrafast synthesis oxygen vacancy LiNi_(0.5-x)Mn_(1.5+x)O_(4)(LNMO)cathode high-temperature-shock lithium-ion batteries

Insight into the development of electrolytes for aqueous zinc metal batteries from alkaline to neutral

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Chinese Chemical Letters 2024年第2期35卷 232-241页

作者： An Duan Sha luo wei Sun School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China

Aqueous zinc metal batteries are considered as promising candidates for next-generation electrochemical energy storage devices,especially for large-scale energy storage,due to the advantages of high-safety,high energy density and low *** the bridge connecting cathode and anode,electrolyte provides a realistic operating *** alkaline and neutral aqueous zinc metal batteries,issues associated with electrolyte and anode are still *** this review,we reveal the development and evolution of electrolytes for aqueous zinc metal batteries from alkaline to neutral via the description of fundamentals and challenges in terms of comparison and *** also elaborate the strategies in electrolytes regulation and highlight the basic roles and progresses in additives engineering.

关键词： Aqueous electrolytes Zinc metal batteries pH-dependent chemistry Electrolyte regulation Additives engineering

The DUF579 proteins GhIRX15s regulate cotton fiber development by interacting with proteins involved in xylan synthesis

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The Crop Journal 2024年第4期12卷 1112-1125页

作者： Mengyun Li Feng Chen Jingwen luo Yanan Gao Jinglong Cai wei zeng Monika S.Doblin Gengqing Huang Wenliang Xu Hubei Key Laboratory of Genetic Regulation and Integrative Biology School of Life SciencesCentral China Normal UniversityWuhan 430079HubeiChina Zhejiang Provincial Key Laboratory of Plant Evolutionary Ecology and Conservation School of Life SciencesTaizhou UniversityTaizhou 318000ZhejiangChina La Trobe Institute for Sustainable Agriculture&Food School of AgricultureBiomedicine and EnvironmentLa Trobe UniversityBundooraVIC 3086Australia

Cotton provides the most abundant natural fiber for the textile *** mature cotton fiber largely consists of secondary cell walls with the highest proportion of cellulose and a small amount of hemicellulose and *** dissect the roles of hemicellulosic polysaccharides during fiber development,four IRREGULAR XYLEM 15(IRX15)genes,GhIRX15-1/-2/-3/-4,were functionally characterized in *** genes encode DUF579 domain-containing proteins,which are homologs of AtIRX15 involved in xylan *** four GhIRX15 genes were predominantly expressed during fiber secondary wall thickening,and the encoded proteins were localized to the Golgi *** GhIRX15 gene could restore the xylan deficient phenotype in the Arabidopsis irx15irx15l double *** of GhIRX15s in cotton resulted in shorter mature fibers with a thinner cell wall and reduced cellulose content as compared to the wild ***,GhIRX15-2 and GhIRX15-4 formed homodimers and *** addition,the GhIRX15s showed physical interaction with glycosyltransferases GhGT43C,GhGT47A and GhGT47B,which are responsible for synthesis of the xylan backbone and reducing end ***,the GhIRX15s can form heterocomplexes with enzymes involved in xylan modification and side chain synthesis,such as GhGUX1/2,GhGXM1/2 and *** findings suggest that GhIRX15s participate in fiber xylan biosynthesis and modulate fiber development via forming large multiprotein complexes.

关键词： Cotton fiber Xylan biosynthesis GhIRX15s Protein-protein interaction Protein complexes

Effects of Number of Bleed Holes on Shock-Wave/Boundary-Layer Interactions in a Transonic Compressor Stator

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Journal of Thermal Science 2024年第2期33卷 611-624页

作者： LI Bai ZHOU Xun luo Lei DU wei School of Energy Science and Engineering Harbin Institute of TechnologyHarbin150001China

An extensive numerical investigation is conducted to characterize the flow separation control in a transonic compressor cascade with a porous *** bleed holes are arranged on the suction surface in a single row,two staggered rows and three staggered *** each bleed scheme,five bleed pressure ratios are examined at an inlet Mach number of *** results indicate that the aerodynamic performance of the cascade is significantly improved by the porous *** the single-row scheme,the maximum reduction in total pressure losses is 57%.For the two-staggered-row and three-staggered-row schemes,there is an optimal bleed pressure ratio of 1.0,and the maximum reductions in total pressure loss are 68% and 75%,*** low loss in the cascade is due to the well-controlled boundary *** new local supersonic region created by the bleed hole is the key reason for the improved boundary *** vortex induced by side bleeding provides another mechanism for delaying flow *** the bleed holes could create multiple local supersonic regions,which reduce the range of the adverse pressure gradient that the boundary layer needs to *** is the reason why cascades with more bleed holes perform better.

关键词： transonic compressor stator shock wave/boundary layer interaction porous bleed number of bleed holes

Numerical analysis of the effects of subgrade settlement on top-down cracking in epoxy asphalt pavement

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Science China Technological Sciences 2024年第10期67卷 3308-3320页

作者： JIANG XiuJie HUANG wei luo Sang wei Ya KONG weiYi DU KaiJun School of Transportation Southeast University Intelligent Transportation System Research Center Southeast University Department of Civil Engineering Tsinghua University Nanjing Modern Multimodal Transportation Laboratory

Epoxy asphalt pavement cracking caused by subgrade settlement is detrimental to the long-term safe service of roads. A threedimensional finite element model of epoxy asphalt pavement is established to investigate the effects of subgrade settlement on the propagation of top-down cracking(TDC). The contour integral method is utilized to calculate the stress intensity factor(SIF)at the crack tip, and then the extended finite element method(XFEM) is used to analyze the propagation behavior of TDC under combined subgrade settlement and traffic loading. The results of these analyses indicate that increased subgrade settlement,stiffer surface layers, and softer bases will increase the SIF, resulting in a faster crack propagation rate. It is suggested that the use of epoxy asphalt materials in pavement structures can allow more subgrade settlement than conventional asphalt ***, when the base layer modulus is higher than 12500 MPa, the increase in surface modulus can decrease crack propagation length. Sensitivity analysis results demonstrate that subgrade settlement has the most significant impact on TDC propagation. The conclusions of this study are expected to provide a theoretical basis for crack prevention in the design and maintenance of pavement structures.

关键词： epoxy asphalt pavement subgrade settlement XFEM stress intensity factor crack propagation

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Solid-state atomic hydrogen as a broad-spectrum RONS scavenger for accelerated diabetic wound healing

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National Science Review 2024年第2期11卷 196-206页

作者： Man luo Qin Wang Gang Zhao wei Jiang Cici zeng Qingao Zhang Ruyu Yang Wang Dong Yunxi Zhao Guozhen Zhang Jun Jiang Yucai Wang Qing Zhu Key Laboratory of Precision and Intelligent Chemistry School of Chemistry and Materials Science University of Science and Technology of China Department of Radiology The First Affiliated Hospital of University of Science and Technology of China Division of Life Sciences and Medicine University of Science and Technology of China Shenzhen Senior High School Institute of Intelligent Innovation Henan Academy of Sciences

Hydrogen therapy shows great promise as a versatile treatment method for diseases associated with the overexpression of reactive oxygen and nitrogen species（RONS）. However, developing an advanced hydrogen therapy platform that integrates controllable hydrogen release, efficient RONS elimination, and biodegradability remains a giant technical challenge. In this study, we demonstrate for the first time that the tungsten bronze phase H0.53WO3（HWO） is an exceptionally ideal hydrogen carrier, with salient features including temperature-dependent highly-reductive atomic hydrogen release and broad-spectrum RONS scavenging capability distinct from that of molecular hydrogen. Moreover, its unique p H-responsive biodegradability ensures post-therapeutic clearance at pathological sites. Treatment with HWO of diabetic wounds in an animal model indicates that the solid-state atomic H promotes vascular formation by activating M2-type macrophage polarization and anti-inflammatory cytokine production, resulting in acceleration of chronic wound healing. Our findings significantly expand the basic categories of hydrogen therapeutic materials and pave the way for investigating more physical forms of hydrogen species as efficient RONS scavengers for clinical disease treatment.

关键词： atomic hydrogen RONS scavenger inflammatory regulation diabetic wound healing hydrogen therapy