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Science China Chemistry 2024年第9期67卷 2982-2988页

作者： En-He Huang Li-Gao Liu You-Wei Yin Hao-Xuan Dong ji-jia zhou Xin Lu Bo zhou Long-Wu Ye Key Laboratory for Chemical Biology of Fujian Province and State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

α-Imino metal carbenes are versatile intermediates in organic synthesis,and have broad applications in the assembly of divergent ***,the catalytic enantioselective desymmetrization based onα-imino metal carbenes has not been developed to ***,we disclose an enantioselective desymmetrizing C(sp^(2))-H functionalization of azide-ynamides viaα-imino copper carbenes,leading to the efficient assembly of divergent chiral indoloazepines in generally moderate to excellent yields with high ***,this reaction represents the first enantioselective desymmetrization based onα-imino metal *** synthetic transformations and biological tests show the potential utility of this ***,computational studies are employed to elucidate the reaction mechanism and the origin of enantioselectivity.

关键词： enantioselective desymmetrization metal carbenes copper catalysis nitrene transfer alkynes

Copper-catalyzed enantioselective desymmetrizing C（sp）–H functionalization of azide-ynamides via α-imino copper carbenes

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Science China Chemistry 2024年

作者： En-He Huang Li-Gao Liu You-Wei Yin Hao-Xuan Dong ji-jia zhou Xin Lu Bo zhou Long-Wu Ye Key Laboratory for Chemical Biology of Fujian Province and State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences

α-Imino metal carbenes are versatile intermediates in organic synthesis, and have broad applications in the assembly of divergent N-heterocycles. However, the catalytic enantioselective desymmetrization based on α-imino metal carbenes has not been developed to date. Herein, we disclose an enantioselective desymmetrizing C（sp2）–H functionalization of azide-ynamides via α-imino copper carbenes, leading to the efficient assembly of divergent chiral indoloazepines in generally moderate to excellent yields with high enantioselectivities. Notably, this reaction represents the first enantioselective desymmetrization based on α-imino metal carbenes. Further synthetic transformations and biological tests show the potential utility of this method. Moreover,computational studies are employed to elucidate the reaction mechanism and the origin of enantioselectivity.

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Historical biogeography and evolutionary diversification of Lilium(Liliaceae): New insights from plastome phylogenomics

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Plant Diversity 2024年第2期46卷 219-228页

作者： Nian zhou Ke Miao Changkun Liu Linbo jia jinjin Hu Yongjiang Huang Yunheng ji CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education College of Life SciencesSichuan UniversityChengduSichuan 610065China Yunnan Key Laboratory for Integrative Conservation of Plant Species with Extremely Small Population Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China

Here, we infer the historical biogeography and evolutionary diversification of the genus Lilium. For this purpose, we used the complete plastomes of 64 currently accepted species in the genus Lilium(14plastomes were newly sequenced) to recover the phylogenetic backbone of the genus and a timecalibrated phylogenetic framework to estimate biogeographical history scenarios and evolutionary diversification rates of Lilium. Our results suggest that ancient climatic changes and geological tectonic activities jointly shaped the distribution range and drove evolutionary radiation of Lilium, including the Middle Miocene Climate Optimum(MMCO), the late Miocene global cooling, as well as the successive uplift of the Qinghai-Tibet Plateau(QTP) and the strengthening of the monsoon climate in East Asia during the late Miocene and the Pliocene. This case study suggests that the unique geological and climatic events in the Neogene of East Asia, in particular the uplift of QTP and the enhancement of monsoonal climate, may have played an essential role in formation of uneven distribution of plant diversity in the Northern Hemisphere.

关键词： Asian monsoon Climatic changes Distribution range Evolutionary complexity Radiative diversification Species diversity Qinghai-Tibet Plateau(QTP)

Ceramic-based meta-material absorber with high-temperature stability

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Rare Metals 2024年第9期43卷 4433-4440页

作者： Xing-Cong Chen Wei-jia Luo Run-Ni Zhao Yong-Zheng Wen ji zhou State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua University

With the continuous exploration of uncharted and extreme environments,enhanced temperature robustness of passive devices has become particularly *** this study,a ceramic-based meta-material absorber with exceptional temperature stability is developed using a fusion design approach that combines rare metal-based tungsten bronze structural ceramics and ***,the absorbance of the meta-material array based on Mie resonance exceeds 49.0%in both waveguides and free space,approaching the theoretical *** to impedance analysis,the absorption performance can be distinctly correlated with the dielectric loss （Q_f）.Notably,the high-temperature robustness is verified to still be effective at 400℃.These advancements in our design allow for the use of monolithic materials in fabricating temperature-stable perfect absorbers,providing greater freedom in the dielectric performance and expanding their potential applications,including in space exploration and 5G millimeter-wave scenarios.

关键词： Meta-material absorber Microwave absorption Miniaturization Rare metal-based ceramics Temperature robustness

Small Cycles Property of Some Cremer Rational Maps and Polynomials

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Chinese Annals of Mathematics,Series B 2024年第1期45卷 123-136页

作者： Rong FU ji zhou Faculty of Science Yibin UniversityYibin 644000SichuanChina Department of Mathematical Sciences Sichuan Normal UniversityChengdu 610066China

This paper concerns the linearization problem on rational maps of degree d≥2 and polynomials of degree d>2 from the perspective of *** authors introduce a set l_(∞) of irrational numbers and show that if α∈l_(∞),then any rational map is not linearizable and has infinitely many cycles in every neighborhood of the fixed point with multiplier λ=e^(2πiα),Adding more constraints to cubic polynomials,they discuss the above problems by polynomial-like *** the family of polynomials,with the help of Yoccoz's method,they obtain its maximum dimension of the set in which the polynomials are non-linearizable.

关键词： Irrationally indifferent fixed point Linearization problem Small cycles property

Bayesian inference of neutron-skin thickness and neutron-star observables based on effective nuclear interactions

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 97-105页

作者： jia zhou Jun Xu Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China School of Physics Science and Engineering Tongji UniversityShanghai 200092China

We have obtained the constraints on the density dependence of the symmetry energy from neutron-skin thickness data by parityviolating electron scatterings and neutron-star observables using a Bayesian approach,based on the standard Skyrme-HartreeFock(SHF)model and its extension as well as the relativistic mean-field(RMF)*** the neutron-skin thickness data(neutron-star observables)mostly constrain the symmetry energy at subsaturation(suprasaturation)densities,they may more or less constrain the behavior of the symmetry energy at suprasaturation(subsaturation)densities,depending on the energy-density functional *** showing the final posterior density dependence of the symmetry energy,we also compare the slope parameters of the symmetry energy at 0.10 fm-3as well as the values of the symmetry energy at twice saturation density from three effective nuclear *** present work serves as a comparison study based on relativistic and non-relativistic energy-density functionals,for constraining the nuclear symmetry energy from low to high densities using a Bayesian approach.

关键词： symmetry energy neutron skin neutron star

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HeterMM: applying in-DRAM index to heterogeneous memory-based key-value stores

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Frontiers of Computer Science 2024年第4期18卷 215-217页

作者： Yunhong ji Wentao HUANG Xuan zhou School of Information Renmin University of ChinaBeijing 100872China School of Computing National University of SingaporeSingapore 117417Singapore School of Data Science and Engineering East China Normal UniversityShanghai 200062China

1 Introduction Emerging byte-addressable storage technologies,such as NVM(Non-Volatile Memory),provide a more cost-effective and larger-capacity alternative to DRAM(Dynamic Random Access Memory)[1],presenting new opportunities to address the high cost,limited capacity,and volatility of in-memory key-value(KV)*** efforts have been dedicated to redesigning conventional structures on ***,they were challenged by the substantial engineering cost and increased complexity to be integrated into existing ***,a general framework to apply existing indexes to KV stores on NVM becomes more attractive[2].

关键词： stores applying value

Predicting the International Roughness Index of JPCP and CRCP Rigid Pavement:A Random Forest(RF)Model Hybridized with Modified Beetle Antennae Search(MBAS)for Higher Accuracy

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 1557-1582页

作者： zhou ji Mengmeng zhou Qiang Wang jiandong Huang College of Civil and Environmental Engineering Hunan University of Science and EngineeringYongzhou425006China School of Mines China University of Mining and TechnologyXuzhou221116China School of Civil Engineering Guangzhou UniversityGuangzhou510006China

To improve the prediction accuracy of the International Roughness Index(IRI)of Jointed PlainConcrete Pavements(JPCP)and Continuously Reinforced Concrete Pavements(CRCP),a machine learning approach is developed in this study for the modelling,combining an improved Beetle Antennae Search(MBAS)algorithm and Random Forest(RF)*** 10-fold cross-validation was applied to verify the reliability and accuracy of the model proposed in this *** importance scores of all input variables on the IRI of JPCP and CRCP were analysed as *** results by the comparative analysis showed the prediction accuracy of the IRI of the newly developed MBAS and RF hybrid machine learning model(RF-MBAS)in this study is higher,indicated by the RMSE and R values of 0.2732 and 0.9476 for the JPCP as well as the RMSE and R values of 0.1863 and 0.9182 for the *** accuracy of this obtained result far exceeds that of the IRI prediction model used in the traditional Mechanistic-Empirical Pavement Design Guide(MEPDG),indicating the great potential of this developed *** importance analysis showed that the IRI of JPCP and CRCP was proportional to the corresponding input variables in this study,including the total joint faulting cumulated per KM(TFAULT),percent subgrade material passing the 0.075-mm Sieve(P_(200))and pavement surface area with flexible and rigid patching(all Severities)(PATCH)which scored higher.

关键词： Cement pavement JPCP CRCP RF-MBAS IRI

Universal dynamic scaling and Contact dynamics in quenched quantum gases

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Frontiers of physics 2024年第2期19卷 213-220页

作者： jia-Nan Cui Zhengqiang zhou Mingyuan Sun School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China State Key Lab of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China

Recently universal dynamic scaling is observed in several systems,which exhibit a spatiotemporal self-similar scaling behavior,analogous to the spatial scaling near phase *** latter one arises from the emergent continuous scaling *** by this,we investigate the possible relation between the scaling dynamics and the continuous scaling symmetry in this *** derive a theorem that the scaling invariance of the quenched Hamiltonian and the initial density matrix can lead to the universal dynamic *** is further demonstrated both in a two-body system analytically and in a many-body system *** the latter one,we calculate the dynamics of quantum gases quenched from the zero interaction to a finite interaction via the non-equilibrium high-temperature virial expansion.A dynamic scaling of the momentum distribution appears in certain momentum-time windows at unitarity as well as in the weak interacting ***,this universal scaling dynamics persists approximately with smaller scaling exponents even if the scaling symmetry is fairly *** findings may offer a new perspective to interpret the related *** also study the Contact dynamics in the BEC−BCS ***,the half-way time displays a maximum near unitarity while some damping oscillations occur on the BEC side due to the dimer state,which can be used to detect possible two-body bound states in experiments.

关键词： dynamic scaling Contact dynamics quantum gases cold atom quench dynamics virial expansion continuous scaling symmetry

Perturbation of autophagy pathways in murine alveolar macrophage by 2D TMDCs is chalcogen-dependent

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Journal of Environmental Sciences 2024年第1期135卷 97-107页

作者： Xiaofei zhou Weitao jin Rui Zhang Xuan Mao jianbo jia Hongyu zhou College of Science&Technology Hebei Agricultural UniversityHuanghua 061100China Institute of Environmental Research at Greater Bay Area Key Laboratory for Water Quality and Conservation of the Pearl River DeltaMinistry of EducationGuangzhou UniversityGuangzhou 510006China

Increasing risks of incidental and occupational exposures to two-dimensional transition metal dichalcogenides(2D TMDCs)due to their broad application in various areas raised their public health *** the composition-dependent cytotoxicity of 2D TMDCs has been well-recognized,how the outer chalcogenide atoms and inner transition metal atoms differentially contribute to their perturbation on cell homeostasis at non-lethal doses remains to be *** the present work,we compared the autophagy induction and related mechanisms in response to WS_(2),NbS_(2),WSe_(2)and Nb Se_(2)nanosheets exposures in MH-S murine alveolar *** these 2D TMDCs had comparable physicochemical properties,overall cytotoxicity and capability in triggering autophagy in MH-S cells,but showed outer chalcogen-dependent subcellular localization and activation of autophagy ***,WS_(2)and NbS_(2)nanosheets adhered on the cell surface and internalized in the lysosomes,and triggered m TOR-dependent activation of ***,WSe_(2)and Nb Se_(2)nanosheets had extensive distribution in cytoplasm of MH-S cells and induced autophagy in an m TOR-independent ***,the 2D TMDCs-induced perturbation on autophagy aggravated the cytotoxicity of respirable benzo[a]*** findings provide a deeper insight into the potential health risk of environmental 2D TMDCs from the perspective of homeostasis perturbation.

关键词： Chalcogen group Autophagy pathway Cell function Endosomal escape Inhalation toxicity