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Synergistic asymmetric diarylation of tethered alkenes via C–H functionalization of simple(hetero)arenes

Science China Chemistry 2024年第8期67卷 2710-2718页

作者： Jian Yao Can Zhao Lili Shao Xiaohong huo Xiaoming Wang Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Frontiers Science Center for Transformative MoleculesSchool of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China

By virtue of the atom-and step-economy, utilization of simple arenes as a supplant of pre-prepared aryl metal species or aryl halides for the synthesis of arylated chiral molecules has attracted great attention from the synthetic community. While transition-metal-catalyzed enantioselective diarylation of tethered alkenes has been employed to prepare important chiral cyclic compounds, the direct use of simple arenes as aryl precursors is still underdeveloped, probably due to the difficulties in the effective control of the reactivity, site-selectivity and/or enantioselectivity. Herein we report an asymmetric Pd/Ag dual metal catalytic system for the non-directed, site-and enantioselective domino Heck/intermolecular C–H functionalization of *** studies showed that Pd and Ag act in cooperation in the catalysis and the chiral bisphosphine ligand plays a bifunctional role, i.e., assisting the silver species in the cleavage of the aryl C–H bond, while inducing the enantioselectivity on direct complexation with palladium. This method provides an efficient approach to the corresponding chiral oxindoles with good enantiomeric excesses from a broad scope of arenes, including fluoroarenes, heteroarenes and several complex products derived from medicines or natural products.

关键词： asymmetric Pd/Ag dual metal catalytic system simple arenes C–H functionalization bifunctional role chiral oxindoles

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The de Haas-van Alphen quantum oscillations in the kagome metal RbTi_(3)Bi_(5)

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Chinese Physics B 2024年第10期33卷 356-361页

作者： Zixian dong Lei Shi Bin Wang Mengwu huo Xing Huang Chaoxin Huang Peiyue Ma Yunwei Zhang Bing Shen Meng Wang Center for Neutron Science and Technology Guangdong Provincial Key Laboratory of Magnetoelectric Physics and DevicesSchool of PhysicsSun Yat-Sen UniversityGuangzhou 510275China

The kagome system has attracted great interest in condensed matter physics due to its unique structure that canhost various exotic states such as superconductivity(SC),charge density waves(CDWs)and nontrivial topological *** topological semimetal RbTi_(3)Bi_(5)consisting of a Ti kagome layer shares a similar crystal structure to the topologicalcorrelated materials AV_(3)Sb_(5)(A=K,Rb,Cs)but without the absence of CDW and *** de Haas-van Alphenoscillation measurements are performed on single crystals of RbTi_(3)Bi_(5)to pursue nontrivial topological physics and *** this with theoretical calculations,the detailed Fermi surface topology and band structure are investigated.A two-dimensional Fermi pocket b is revealed with a light effective mass,consistent with the semimetal *** fan diagram of RbTi_(3)Bi_(5)reveals a zero Berry phase for the b oscillation in contrast to that of CsTi_(3)Bi_(5).Theseresults suggest that kagome RbTi_(3)Bi_(5)is a good candidate for exploring nontrivial topological exotic states and topologicalcorrelated physics.

关键词： oscillation Fermi surface band structure

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Shear band evolution and acoustic emission characteristics of sandstone containing non-persistent flaws

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 497-513页

作者： Shuting Miao Peng-Zhi Pan Chuanqing Zhang Lei huo State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China CASIC Research Institute of Intelligent Decision Engineering Wuhan430040China

Direct shear tests were conducted on sandstone specimens under different constant normal stresses to study the coalescence of cracks between non-persistent flaws and the shear sliding characteristics of the shear-formed *** image correlation and acoustic emission(AE)techniques were used to monitor the evolution of shear bands at the rock bridge area and microcracking *** experimental results revealed that the shear stresses corresponding to the peak and sub-peak in the stressdisplacement curve are significantly affected by the normal *** localization bands emerged at both the tip of joints and the rock bridge,and their extension and interaction near the peak stress caused a surge in the AE hit rate and a significant decrease in the AE b *** and curvilinear strain bands were detected at low normal stress,while high normal stress generally led to more microcracking events and longer coplanar cracks at the rock bridge ***,an increase in normal stress resulted in a higher AE count rate and more energetic AE events during friction sliding along the shearformed *** was observed that the elastic energy released during the crack coalescence at the prepeak stage was much greater than that released during friction sliding at the post-peak *** than 75%of AE events were located in the low-frequency band(0e100 kHz),and this proportion continued to rise with increasing normal ***,more AE events of low AF value and high RA value were observed in specimens subjected to high normal stress,indicating that greater normal stress led to more microcracks of shear nature.

关键词： Shear band evolution Acoustic emission(AE) Crack coalescence Normal stress Shear sliding

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The Role of Consumer Privacy Concerns in Shaping Platform Strategy for Online Markets

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Journal of the Operations Research Society of China 2024年第2期12卷 363-386页

作者： Jin-Kun Yang Yong-Rui Duan Jia-Zhen huo School Economics and Management Tongji UniversityShanghai 200092China

We investigate the effects of consumer privacy concerns on the pricing and personal data collection strategy of an online *** online platform derives revenues from disclosing consumer information to *** compete for the information in order to enable them to price discriminate and thus derive revenues from consumer purchases.A novel aspect of our research is that we allow the online platform to sell only a subset of consumer *** develop analytical models where consumers can/cannot protect their *** analysis yields three main ***,in the monopoly case,we find that when the consumer privacy disclosure aversion cost is relatively low,it is optimal for the platform to sell all consumer information to the ***,in the duopoly case,we illustrate that when the consumer privacy disclosure aversion cost is relatively low,the platform will sell all consumer information to only one firm;when the cost is moderate,the platform will choose to sell the information of only some consumers and to only one firm;when the cost is relatively high,the platform will select only some of the consumers and sell their information to both ***,it will be better for the platform to provide the information protection service for free when the privacy cost is low.

关键词： Price discrimination User privacy Consumer information Two-sided market Privacy disclosure aversion cost

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A new era in healthcare:The integration of artificial intelligence and microbial

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Medicine in Novel Technology and Devices 2024年第3期23卷 22-31页

作者： Daliang huo Xiaogang Wang School of Engineering Medicine Beihang UniversityBeijing100191China The Third Affiliated Hospital of Southern Medical University Southern Medical UniversityGuangzhou528300China

The convergence of artificial intelligence(AI)and microbial therapeutics offers promising avenues for novel discoveries and therapeutic *** the exponential growth of omics datasets and rapid advancements in AI technology,the next generation of AI is increasingly prevalent in microbiology *** microbial research,AI is instrumental in the classification and functional annotation of *** learning algorithms facilitate efficient and accurate categorization of microbial taxa,enabling the identification of functional traits and metabolic pathways within microbial ***,AI-driven protein design strategies hold promise for engineering enzymes with enhanced catalytic activities and *** predicting protein structures,functions,and interactions,AI algorithms enable the rational design of proteins and enzymes tailored for specific *** systems are already present in clinical microbiology laboratories in the form of expert rules used by some automated susceptibility testing and identification *** the future,microbiology technologists will rely more heavily on AI for initial screening,allowing them to focus on diagnostic challenges and complex technical ***-driven approaches hold immense promise in advancing our understanding of microbial ecosystems,accelerating drug discovery processes,and fostering the development of groundbreaking therapeutic *** review aims to summarize common algorithms in AI and their applications within microbiology and synthetic *** provide a comprehensive evaluation of AI’s utility in microbial research,discussing both its advantages and ***,we explore future research directions and the bottlenecks faced by AI in the microbial field.

关键词： Artificial intelligence(AI) Microbial therapeutics Omics data analysis Machine learning Protein design

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Measurements of neutron energy spectra of 9Be(d,n)10B reaction with a thick beryllium target

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Chinese Physics C 2021年第2期45卷 398-405页

作者： Shuang-Jiao Zhang Zhi-Jie Hu Zhi-Ming Hu Chao Han Xiao-Hou Bai Chang-Qi Liu Chang Huang Qin Xie dong-ying huo Kang Wu Yang-Bo Nie Yan-Yan Ding Kai Zhang Yu Zhang Zhi-Yong Deng Rui Guo Zheng Wei Ze-En Yao School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Engineering Research Center for Neutron Application Technology Ministry of EducationLanzhou UniversityLanzhou 730000China Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China Nuclear Power Institute of China Chengdu 610000China

Novel measurements of the neutron energy spectra of the 9Be(d,n)10B reaction with a thick beryllium target are performed using a fast neutron time-of-flight(TOF)spectrometer for the neutron emission angles θ=0°and 45°,and the incident deuteron energies are 250 and 300 keV,*** neutron contributions from the 9Be(d,n)10B reaction are distributed relatively independently for the ground state and the first,second,and third excited states of *** branching ratios of the 9Be(d,n)10B reaction for the different excited states of 10B are obtained for the neutron emission angles θ=0°and 45°,and the incident deuteron energies are 250 and 300 keV,*** branching ratio of the 9Be(d,n)10B reaction for the third excited state decreases with increase in the incident deuteron energy,and the branching ratios for the ground state and the second excited state increase with increase in the neutron emission angle.

关键词： neutron energy spectrum branching ratio 9Be(d n)10B reaction neutron time-of-flight spectrometer

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Recent progress in polymerization-induced self-assembly:From the perspective of driving forces

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Aggregate 2024年第1期5卷 47-66页

作者： Zizhuo Zhao Shujing Lei Min Zeng Meng huo Department of Chemistry Key Laboratory of Surface and Interface Science of Polymer Materials of Zhejiang ProvinceZhejiang Sci-Tech UniversityHangzhouP.R.China Department of Chemistry University of WarwickCoventryUK

Polymerization-induced self-assembly(PISA)enables the simultaneous growth and self-assembly of block copolymers in one pot and therefore has developed into a high-efficiency platform for the preparation of polymer assemblies with high concentration and excellent *** the past decade,the driving force of PISA has extended from hydrophobic interactions to other supramolecular interactions,which has greatly innovated the design of PISA,enlarged the monomer/solvent toolkit,and endowed the polymer assemblies with intrinsic dynamicity and *** unravel the important role of driving forces in the formation of polymeric assemblies,this review summarized the recent development of PISA from the perspective of driving *** by this goal,here we give a brief overview of the basic principles of PISA and systematically discuss the various driving forces in the PISA system,including hydrophobic interactions,hydrogen bonding,electrostatic interactions,andπ-π***,PISA systems that are driven and regulated by crystallization or liquid crystalline ordering were also highlighted.

关键词： driving forces electrostatic interactions hydrogen bonding hydrophobic interactions polymerizationinduced self-assembly

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The impact of supply chain resilience on customer satisfaction and financial performance:A combination of contingency and configuration approaches

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Journal of Management Science and Engineering 2024年第1期9卷 38-52页

作者： Baofeng huo Dan Li Minhao Gu College of Management and Economics Tianjin UniversityTianjin300072China

Supply chain resilience(SCR)refers to a supply chain's(SC's)ability to recover from disruptions timely and *** study uses a combination of contingency and configuration approaches to examine the direct and contingent relationships between SCR dimensions(i.e.,internal,supplier,and customer resilience)and *** analyzes survey data collected from 206 Chinese *** results show that the three SCR dimensions are positively related to customer satisfaction,whereas customer resilience has no direct contribution to financial *** resilience moderates the relationship between supplier resilience and performance(negative for customer satisfaction and positive for financial performance).A taxonomy for SCR was developed based on internal,supplier,and customer resilience,providing a holistic perspective for examining the performance discrepancies among four different SCR patterns:high externalleaning,high uniform,medium uniform,and low *** findings offer insights for managers in building SCR from the crisis-management process.

关键词： Supply chain resilience Risk management Taxonomy Performance China

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Applying Machine Learning Approach to Explore Childhood Circumstances and Self-Rated Health in Old Age-China and the US,2020-2021

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China CDC weekly 2024年第11期6卷 213-218,I0008-I0013页

作者： Shutong huo Derek Feng Thomas M.Gill Xi Chen Department of Health Society&BehaviorPublic HealthUniversity of CaliforniaIrvineCAUSA Department of Statistics and Data Science Yale UniversityNew HavenCTUS Department of Internal Medicine Yale School of MedicineNew HavenCTUS Department of Health Policy and Management Yale School of Public HealthNew HavenCTUS Department of Economics Yale UniversityNew HavenCTUS.

Introduction:Childhood circumstances impact senior health,prompting the introduction of machine learning methods to assess their individual and collective contributions to senior ***:Using health and retirement study(HRS)and China Health and Retirement Longitudinal Study(CHARLS),we analyzed 2,434 American and 5,612 Chinese participants aged 60 and *** inference trees and forests were employed to estimate the influence of childhood circumstances on self-rated health(SRH).Results:The conventional method estimated higher inequality of opportunity(IOP)values in both China(0.039,accounting for 22.67%of the total Gini coefficient 0.172)and the US(0.067,accounting for 35.08%of the total Gini coefficient 0.191).In contrast,the conditional inference tree yielded lower estimates(China:0.022,accounting for 12.79%of 0.172;US:0.044,accounting for 23.04%of 0.191),as did the forest(China:0.035,accounting for 20.35%of 0.172;US:0.054,accounting for 28.27%of 0.191).Childhood health,financial status,and regional differences were key determinants of senior *** conditional inference forest consistently outperformed others in predictive accuracy,as demonstrated by lower out-of-sample mean squared error(MSE).Discussion:The findings emphasize the need for early-life interventions to promote health equity in aging *** learning showcases the potential in identifying contributing factors.

关键词： collective inequality estimates

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Unusual photocarrier and coherent phonon dynamics behaviors of layered PdSe_(2)unveiled by ultrafast spectroscopy of the edge surface

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 143-152页

作者： Tiantian Yun Changfu huo Jinluo Cheng Zhi-Bo Liu Xiao-Qing Yan Key Laboratory of Weak-Light Nonlinear Photonics Ministry of EducationSchool of PhysicsNankai UniversityTianjin 300071China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China GPL Photonics Laboratory Key Laboratory of Luminescence Science and TechnologyChinese Academy of Sciences&State Key Laboratory of Luminescence Science and ApplicationsChangchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China

Layered materials exhibit different electronic and phonon properties along in-plane and out-of-plane directions;existing studies focus on their in-plane behaviors,and the influence of such anisotropies on the dynamics of photocarriers and phonons is ***,we fabricate layered PdSe_(2)crystals with flat edge surfaces and compare the time-resolved ultrafast spectroscopies on their basal and edge *** differences in the transient reflection spectroscopies reveal the inconsistent photocarrier and phonon dynamics behaviors on the two surfaces:the slow hot carrier relaxation process is accelerated and the thermoelasticity-induced longitudinal coherent acoustic phonon oscillation completely vanishes on the edge surface,as compared with the basal *** analysis reveals that the inconsistent hot carrier dynamics originate from the anisotropic properties of low-energy phonons in PdSe_(2),and the absence of phonon oscillation on the edge surface results from the wavevector-limited sensitivity of acoustic B_(1u)***,polarization-dependent spectroscopies indicate the diverse optical anisotropies beyond the in-plane of PdSe_(2).This work provides a new method to explore unique physical properties and modulate the optical anisotropy of layered materials.

关键词： PdSe_(2) ultrafast spectroscopy edge surface carrier dynamics coherent phonon oscillation anisotropy

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