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S-,P-stabilized bromoallenes for modular allenylborylation of alkenes

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Science China Chemistry 2024年第1期67卷 360-367页

作者： Jixin Wang Donghao Luo ying hu Zhili Duan Jianlin Yao Konstantin Karaghiosoff jie Li Key Laboratory of Organic Synthesis of Jiangsu Province Suzhou Key Laboratory of Pathogen Bioscience and Anti-infective MedicineCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China Department Chemie Ludwig-Maximilians-Universitat MunchenButenandtstr.5-13Haus F81377 MunichGermany State Key Laboratory and Institute of Elemento-Organic Chemistry Haihe Laboratory of Sustainable Chemical TransformationsCollege of ChemistryNankai UniversityTianjin 300071China

Simultaneously forming a carbon-carbon and a carbon-heteroatom bond in a single step through transition metal-catalyzed alkene difunctionalization strategy has emerged as a powerful tool for synthetic organic *** to the uncontrollable reactivity,direct cross-coupling with bromoallenes as the building blocks for the selective allenation and borylation remains *** herein report a new type of S-and P-stabilized bromoallenes for palladium-catalyzed modular allenation and borylation of alkenes to the divergent synthesis of multiply functionalized allenes in a highly regio-and diastereoselective *** reaction features broad substrate scope and wide functional group compatibility,thus providing a straightforward method to install allenyl and boryl groups across *** experiments highlight the crucial importance of S-,P-stabilization for the oxidative insertion of Pd-species into the allenyl-Br *** facile syntheses of bioactive allenic steroids and exocyclic allenes demonstrate the synthetic utility of this protocol.

关键词： alkene difunctionalization olefins bromoallenes allenylborylation palladium

Light People:*** D C Bradley(FRS)

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Light(Science & Applications) 2024年第9期13卷 1704-1719页

作者： Ruidong Xia ying hu Key Laboratory for Organic Electronics&Information Displays(KLOEID) Jiangsu-Singapore Joint Research Center for Organic/Bio Electronics&Information DisplaysInstitute of Advanced Materials(IAM)Nanjing University of Posts and Telecommunications9 Wenyuan RoadNanjing 210023China Executive Management College of CHN ENERGY North District of Future Science CityChangping DistrictNo.7 Binhe AvenueBeijing 102211China

Editorial,The invention of organic light emitting diodes(LEDs)led to enormous excitement in both academe and industry in the late 1980’***,large area solution processability,roll-to-roll printing,low cost,and environmentally friendly are some of the advantages of organic semiconductor materials,which brought a new horizon for *** with the achievement of organic solar cells,transistors,lasers,and amplifiers,this has demonstrated potential applications of organic semiconductors in displays,lighting,solar energy generation,electronics,sensing and imaging,and many aspects of *** an enlightened conversation with Light:Science&Applications,*** Bradley(FRS),a pioneer in the field,shared his deep insights on past,current,and future exciting developments of organic optoelectronic materials and *** particular,he expressed his opinion on the hot topics related to organic optoelectronics research and application,such as the relationship between organic and inorganic semiconductors and the challenge of electrically pumped organic *** a successful scientist,Donal has also been co-founder of several organic optoelectronics innovation companies and research centers and a long-term academic administrator serving as a Head of Department,Centre Director,and Vice-Rector for Research at Imperial College,Head of the Mathematical,Physical,and Life Sciences Division at the University of Oxford,Vice-President for Research at King Abdullah University of Science and Technology and now Vice-President for Research and Innovation at NEOM U and Executive Director of the NEOM Education,Research and Innovation *** this interview,we also explore the major roles and events in Donal’s career experience from the invention of the first conjugated polymer LED in the world to the set-up of entrepreneurial companies,from Cambridge to Sheffield,Imperial College,and Oxford,from the UK to overseas,and from the establishment of the Cent

关键词： companies Director Bradley

Electrochemical chemoselective thiocarbamylation of late-stage Tyr-containing drugs and peptides

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Science China Chemistry 2024年第10期67卷 3382-3388页

作者： Wan-jie Wei Xin-Yu Wang Hai-Tao Tang Fei-hu Cui Yun-Qi Wu ying-Ming Pan State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources(Ministry of Education of China)Collaborative Innovation Center for Guangxi Ethnic MedicineSchool of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilin 541004China

The synthesis and modification of peptides occupy a unique position in the field of drug development,and the functionalization of amino acids is a valuable strategy as an alternative to peptide ***,the development of tyrosine(Tyr)as a target amino acid is a major challenge in the field of ***,we report an electrochemical radical coupling reaction of labeling tyrosine-containing active drugs and peptides with thiocarbamate derivatives for the first *** tri-component,onepot reaction can be performed smoothly under simple,gentle,and clean electrochemical conditions and is suitable for the functionalization of various Tyr-containing drug molecular derivatives and peptides.

关键词： tyrosine electrochemical radical coupling chemical modification peptides

Changes in extreme high temperature warning indicators over China under different global warming levels

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Science China Earth Sciences 2024年第6期67卷 1895-1909页

作者： Yuxia ZHANG ying SUN Ting hu Chinese Academy of Meteorological Sciences Beijing 100081China National Climate Center Laboratory for Climate StudiesChina Meteorological AdministrationBeijing 100081China

High temperature warning indicators play a pivotal role in meteorological departments,serving as crucial criteria for issuing warnings that guide both social production and daily *** their importance,limited studies have explored the relationship between different global warming levels and changes in high temperature warning *** this study,we analyze data from 2,419 meteorological stations over China and utilize the Coupled Model Intercomparison Project Phase 6(CMIP6)models to examine historical changes in high temperature warning indicators used by the China Meteorological *** evaluate model performance and estimate future changes in these indicators using an annual cycle bias correction *** results indicate that since 1961,the number of high temperature days(TX35d and TX40d)and length of season(TX40d and TX40l)with daily maximum temperature reaching or exceeding 35℃ and 40℃ have increased over *** intensity of high temperatures(TXx)has strengthened and the geographical extent affected by high temperatures has *** 2022,the occurrence of 40℃ high temperatures surges,with Eastern China experiencing a two-day increase in TX40d and an extended seasonal length in TX40l by over five *** CMIP6 models have underestimated the high temperature indictors associated with 35℃ during historical periods,notable difference is not observed between the models and observations for TX40d and TX40l,given their rare ***,future projections,after bias correction,indicate that the increasing trends for 35℃ and 40℃ high temperature days and length of season become more pronounced than the raw projection,suggesting a more severe increase than that anticipated *** global warming intensifies,the high temperature days and length of season are projected to increase non-linearly,while the intensity of high temperatures is expected to increase *** every 1℃ increase in global temperature,the intensity is

关键词： Extreme high temperatures Meteorological warning CMIP6 Global warming levels Future projection

Parametric resonance of axially functionally graded pipes conveying pulsating fluid

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 239-260页

作者： jie JING Xiaoye MAO hu DING Liqun CHEN Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechanoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200444China Shanghai Institute of Aircraft Mechanics and Control Shanghai 200092China

Based on the generalized Hamilton's principle,the nonlinear governing equation of an axially functionally graded(AFG)pipe is *** non-trivial equilibrium configuration is superposed by the modal functions of a simply supported *** the direct multi-scale method,the response and stability boundary to the pulsating fluid velocity are solved analytically and verified by the differential quadrature element method(DQEM).The influence of Young's modulus gradient on the parametric resonance is investigated in the subcritical and supercritical *** general,the pipe in the supercritical region is more sensitive to the pulsating *** nonlinearity changes from hard to soft,and the non-trivial equilibrium configuration introduces more frequency components to the ***,the increasing Young's modulus gradient improves the critical pulsating flow velocity of the parametric resonance,and further enhances the stability of the *** addition,when the temperature increases along the axial direction,reducing the gradient parameter can enhance the response *** work further complements the theoretical analysis of pipes conveying pulsating fluid.

关键词： pipe conveying fluid axially functionally graded supercritical resonance multi-scale method parametric resonance

Nanoforming of transferred metal contacts for enhanced twodimensional field effect transistors

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Nano Research 2024年第4期17卷 3210-3216页

作者： Shuoheng Xu Zheng huang jie Guan Yaowu hu The Institute of Technological Sciences Wuhan UniversityWuhan 430072China School of Power and Mechanical Engineering Wuhan UniversityWuhan 430072China School of Physics Southeast UniversityNanjing 211189China

Two-dimensional transition metal chalcogenides(2D-TMDs)have attracted much attention because of their unique layered structure and physical properties for transistor *** transferred metal contacts on these low-dimensional materials or their homogeneous and heterogeneous multilayers have generated huge interest to avoid deposition *** this paper,we show that there are large physical gaps at both the edge contact and surface contact between the transferred electrodes and the 2D materials.A method called laser shock induced superplastic deformation(LSISD)is proposed to tackle this issue and enhance the performance of the *** enhancement mechanism was investigated by molecular dynamics(MD)simulations of the nanoforming process,atomic force microscopy(AFM),scanning electron microscopy(SEM),transmission electron microscopy(TEM)characterizations of the interfaces,and density functional theory(DFT)*** force effect of laser shock can reduce the contact gap between metals and *** electrical performances of the transistors before and after LSISD,along with MD simulations,are used to find the optimal process *** addition,this paper applies the LSISD method to the short-channel MoS_(2)/graphene vertical transistors to show potential improvement in interface contact and electrical *** paper demonstrates the first report on using mechanical force induced by laser shock to enhance metal–semiconductor interfaces and transistor performances.

关键词： laser shock nanoforming metal-semiconductor contact electronics two-dimensional transistors

Semi-Varying Coefficient Panel Data Model with Technical Indicators Predicts Stock Returns in Financial Market

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Journal of Systems Science & Complexity 2024年第4期37卷 1638-1652页

作者： hu Xuemei PAN ying LI Xiang School of Mathematics and Statistics Chongqing Technology and Business UniversityChongqing 400067China Chongqing Key Laboratory of Social Economy and Applied Statistics Chongqing 400067China Research Center for Economy of Upper Reaches of the Yangtse River Chongqing Technology and Business UniversityChongqing 400067China

Accurately predicting stock returns is a conundrum in financial *** this conundrum can bring huge economic benefits for investors and also attract the attention of all circles of *** this paper the authors combine semi-varying coefficient model with technical analysis and statistical learning,and propose semi-varying coefficient panel data model with individual effects to explore the dynamic relations between the stock returns from five companies:CVX,DFS,EMN,LYB,and MET and five technical indicators:CCI,EMV,MOM,ln ATR,ln RSI as well as closing price(ln CP),combine semi-parametric fixed effects estimator,semi-parametric random effects estimator with the testing procedure to distinguish fixed effects(FE) from random effects(RE),and finally apply the estimated dynamic relations and the testing set to predict stock returns in December 2020 for the five *** proposed method can accommodate the varying relationship and the interactive relationship between the different technical indicators,and further enhance the prediction accuracy to stock returns.

关键词： Fixed effects random effects semi-varying coefficient panel data model stock returns technical indicators

The important role of Turbidity Maximum Zone in sedimentary dynamic of estuarine mangrove swamp

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Frontiers of Earth Science 2024年第1期18卷 219-226页

作者： Tao LIU ying LIU Baoqing hu Key laboratory of Environment Change and Resources Use in Beibu Gulf(Ministry of Education) Nanning Normal UniversityNanning 530001China School of Civil Engineering and Architecture Guangxi UniversityNanning 530004China

Sedimentation is a key process affecting wetland sustainability and carbon burial *** context of sea level rise,climate change and human activities,further understanding about the sedimentary dynamic in wetland is critical in predicting the landscape evolution or the change in carbon burial *** this study,based on the field hydrological observation in a mangrove system in the Nanliu River estuary,we found the net flux of suspended sediment to mangrove is 39−72 kg/m in tidal cycles with Turbidity Maximum Zone(TMZ)forming in surface layer and only is 9−18 kg/m in tidal cycles without *** higher net flux of suspended sediment to mangrove in tidal cycles with TMZ forming in surface layer is attributed to high SSC in rising tide and intense flocculation in *** significant discrepancy in sedimentation rate in the mangrove patches also can be explained by the probability of TMZ forming in the surface layer of *** future,rapid sea level rising may lead to the change of TMZ pattern in estuary,which will result in non-negligible variation in sedimentation rate in *** to the present data of sedimentation rate in wetlands,the fragility of wetlands in river estuary may be miscalculated.

关键词： mangrove wetland sedimentation Turbidity Maximum Zone Nanliu River

Effects of electrolyte balance on intestinal barrier, amino acid metabolism, and mTORC1 signaling pathway in piglets fed lowprotein diets

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Animal Nutrition 2024年第2期17卷 408-417页

作者： Qian Lin Xiaodian Tu Xin Li Feiyang Gou Lin Ding Zeqing Lu jie Feng Yongfei ying Caihong hu College of Animal Sciences Zhejiang University Key Laboratory of Molecular Animal Nutrition (Zhejiang University) Ministry of Education Animal husbandry Technology Promotion and Breeding Livestock and Poultry Monitoring Station of Zhejiang Province

A proper dietary electrolyte balance(dEB) is essential to ensure optimal growth performance of piglets. In the low-protein diet, this balance may be affected by the reduction of soybean meal and the inclusion of high levels of synthetic amino acids. The objective of this experiment was to evaluate the optimal dEB of low-protein diets and its impact on the growth performance of piglets. A total of 108 piglets(initial age of35 d) were randomly divided into 3 groups with 6 replicates of 6 pigs each as follows: low electrolyte diet(LE group; dEB = 150 milliequivalents [mEq]/kg); medium electrolyte diet(ME group; dEB = 250 m Eq/kg);high electrolyte diet(HE group; d EB = 350 mEq/kg). Results indicated that the LE and HE diet significantly decreased the average daily gain, average daily feed intake, and crude protein digestibility(P < 0.05) in piglets. Meanwhile, LE diets disrupted the structural integrity of the piglets' intestines and decreased jejunal tight junction protein(occludin and claudin-1) expression(P < 0.05). Additionally, the pH and HCO3 in the arterial blood of piglets in the LE group were lower than those in the ME and HE groups(P < 0.05).Interestingly, the LE diet significantly increased lysine content in piglet serum(P < 0.05), decreased the levels of arginine, leucine, glutamic acid, and alanine(P < 0.05), and inhibited the mammalian target of rapamycin complex 1(mTORC1) pathway by decreasing the phosphorylation abundance of key proteins. In summary, the dietary electrolyte imbalance could inhibit the activation of the mTORC1 signaling pathway,which might be a key factor in the influence of the dEB on piglet growth performance and intestinal ***, second-order polynomial(quadratic) regression analysis showed that the optimal dEB of piglets in the low-protein diet was 250 to 265 mEq/kg.

关键词： Low-protein Dietary electrolyte balance Piglet Mammalian target of rapamycin complex 1