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Chinese Journal of Chemistry 2022年第12期40卷 1422-1428页

作者： Yuwei liang Linbin Niu Xing-An Liang Shengchun Wang Pengjie Wang Aiwen Lei College of Chemistry and Molecular Sciences Institute for Advanced Studies(IAS)Wuhan UniversityWuhanHubei 430072China

The arylation of C(sp^(3))-H bonds has been a priority research topic in organic synthesis.Minsici reactions have been the powerful methods for C(sp^(3))-C(sp^(2))bonds formation.Despite its mature development,the scopes of arenes are usually suitable for elec-tron-deficient heterocyclic compounds,rather than electron-rich arenes.Herein,we report an electrooxidation-induced alkylation of electron-rich arenes with H_(2) evolution under exogenous oxidant-free conditions,avoiding the utilization of metal catalysts.This pro-tocol is well performed with various electron-rich aniline derivatives and nitrogen-containing heterocyclic compounds.We anticipate that this electro-oxidative C(sp^(3))-H arylation represents an important expansion for the classic arenes alkylation,thereby proving an attractive strategy for the developments of radical cross-coupling chemistry.

关键词： Electrochemistry C-H activation C-C coupling C(sp^(2))-H alkylation Electron-rich arenes

Spreading Speeds of Nonlocal KPP Equations in Heterogeneous Media

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Acta Mathematica Sinica,English Series 2022年第1期38卷 161-178页

作者： xing liang Tao ZHOU School of Mathematical Sciences and Wu Wen-Tsun Key Laboratory of Mathematics University of Science and Technology of ChinaHefei 230026P.R.China

This paper is devoted to studying the asymptotic behavior of the solution to nonlocal Fisher-KPP type reaction diffusion equations in heterogeneous media.The kernel K is assumed to depend on the media.First,we give an estimate of the upper and lower spreading speeds by generalized principal eigenvalues.Second,we prove the existence of spreading speeds in the case where the media is periodic or almost periodic by showing that the upper and lower generalized principal eigenvalues are equal.

关键词： Nonlocal dispersal generalized principal eigenvalue spreading speed heterogeneous media homogenization

Study of Deuteron Separation Energy Based on Bayesian Neural Network Approach

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原子能科学技术 2023年第4期57卷 721-728页

作者： xing Kang liang Yan SUN Xiaojun College of Physics and Technology Guangxi Normal UniversityGuilin 541004China Guangxi Key Laboratory of Nuclear Physics and Technology Guangxi Normal UniversityGuilin 541004China

Deuteron separation energy is not only the basis for validating the nuclear mass models and nucleon-nucleon interaction potential,but also can determine the stability of a nuclide to certain extent.Bayesian neural network(BNN)approach,which has strong predictive power and can naturally give theoretical errors of predicted values,had been successfully applied to study the different kinds of separations except the deuteron separation.In this paper,several typical nuclear mass models,such as macroscopic model BW2,macroscopic-microscopic model WS4,and microscopic model HFB-31,are chosen to study the deuteron separation energy combining BNN approach.The root-mean-square deviations of these models are partly reduced.In addition,the inclusion of physical parameters related to the pair and shell effects in the input layer can further improve the theoretical accuracy for the deuteron separation energy.The results show that the theoretical predictions are more reliable as more physical features of BNN approach are included.

关键词： Bayesian neural network deuteron separation energy pair and shell effects

A Survey of Truck-Drone Routing Problem:Literature Review and Research Prospects

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Journal of the Operations Research Society of China 2022年第2期10卷 343-377页

作者： Yi-Jing liang Zhi-xing Luo School of Traffic and Transport Engineering Changsha University of Science and TechnologyChangsha 410114HunanChina School of Management and Engineering Nanjing UniversityNanjing 210093JiangsuChina

The vehicle routing problem(VRP)has been an important research topic in operations research for decades.The major applications of the VRP arise in transportation,especially the last-mile delivery.In recent years,a growing number of logistic companies introduce drones or unmanned aerial vehicles in the delivery operations.Therefore,the truck-drone routing problem(TDRP),where trucks and drones are scheduled and coordinated to serve customers,vitalizes a new research stream in the literature.In this paper,we provide a comprehensive review on the TDRP.First,two basic models for the traveling salesman problem with drones and vehicle routing problem with drones are presented.Second,researches devoted to the TDRP are classified according to their addressed constraints and features.Third,prevalent algorithms that have been widely used in the existing literature are reviewed and described.Last,potential research opportunities are identified for future study.

关键词： Drone Unmanned aerial vehicle Truck-drone routing Traveling salesman routing Vehicle routing

Caging-Decaging Strategies to Realize Spatiotemporal Control of DNAzyme Activity for Biosensing and Bioimaging

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Chemical Research in Chinese Universities 2022年第4期38卷 902-911页

作者： ZHANG Qian liang Yuyan xing Hang Institute of Chemical Biology and Nanomedicine State Key Laboratory of Chemo/Biosensing and ChemometricsHunan UniversityChangsha410082P.R.China College of Chemistry and Chemical Engineering Hunan UniversityChangsha410082P.R.China College of Biology Hunan UniversityChangsha410082P.R.China

DNAzymes with RNA-cleaving activity have been widely used as biosensing and bioimaging tools for detection of metal ions.Despite the achievements,DNAzyme-based biosensors sometime suffer from false positive signals and unexpected off-target turn-on in biological environments,which are likely due to the unstable nature of the RNA site.Ways to control DNAzyme activity in order to improve the sensing performance remain a significant challenge.To meet the challenge,there is growing interest to develop synthetic strategies that can cage native DNAzyme under undesired conditions and reactivate it in target environment in order to function in a controlled manner.A variety of caging-decaging strategies have been developed to realize spatiotemporal control of the DNAzyme activity,improving its specificity and sensitivity as well as extending its application regimes.In this review,we focus on strategies to regulate the catalytic activity of DNAzyme,highlight the nucleic acid modification chemistries,and summarize three strategies to cage DNAzyme functions.Examples of using caged DNAzyme for bio-applications have also been reviewed in detail.Finally,we provide our perspectives on the potential challenges and opportunities of this emerging research topic that could advance the DNAzyme field.

关键词： RNA-cleaving DNAzyme Caging-decaging strategy Spatiotemporal control Biosensing Bioimaging

Precise nano-programmed ferroptosis with enhanced tumor chemotherapy

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中国科学：材料科学（英文版） 2020年第10期63卷 2086-2088页

作者： xing-Jie liang College of Nanoscience and Technology University of Chinese Academy of SciencesBeijing 100049China Laboratory of Controllable Nanopharmaceuticals CAS Key Laboratory for Biomedical Effects of Nanomaterials and NanosafetyNational Center for Nanoscience and Technology of ChinaChinese Academy of Sciences(CAS)Beijing 100190China CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology of ChinaBeijing 100190China

Cancer treatment is one of the greatest challenges in biomedical research,and the development of novel tumor-inhibition mechanisms has long been a topic of interest for researchers in this field.Ferroptosis is one such candidate that holds promise for clinical translation.It is a recently discovered non-apoptotic model of regulated cell death that shows high iron-dependence.

关键词： Cancer clinical chemotherapy

Structure,far-infrared spectroscopy,microwave dielectric properties,and improved low-temperature sintering characteristics of tri-rutile Mg_(0.5)Ti_(0.5)TaO_(4) ceramics

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Journal of Advanced Ceramics 2023年第2期12卷 296-308页

作者： Hongyu YANG liang CHAI Guangchao liang Mengjiang xing Zixuan FANG xing ZHANG Tianying QIN Enzhu LI Academy of Advanced Interdisciplinary Research Xidian UniversityXi’an 710071China National Engineering Research Center of Electromagnetic Radiation Control Materials University of Electronic Science and Technology of ChinaChengdu 610054China Key Laboratory of Multi-Spectral Absorbing Materials and Structures of Ministry of Education University of Electronic Science and Technology of ChinaChengdu 610054China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China Sichuan Province Key Laboratory of Information Materials and Devices Application Chengdu University of Information TechnologyChengdu 610225China

In this study,tri-rutile type Mg_(0.5)Ti_(0.5)TaO_(4) ceramics were synthesized,where the structure–property relationship,especially the structural configuration and intrinsic dielectric origin of Mg_(0.5)Ti_(0.5)TaO_(4) ceramics,and the low-firing characteristics were studied.It is found that the tri-rutile structural type is unambiguously identified through the Rietveld refinement analysis,the selected area electron diffraction(SAED),and the high-resolution transmission electron microscopy(HRTEM)along the[110]zone axis.With the increase in sintering temperature,the densification and uniformity of crystal growth play important roles in regulating the microwave dielectric properties of Mg_(0.5)Ti_(0.5)TaO_(4) ceramics.Intrinsically,theoretical dielectric properties calculated by the far-infrared reflective spectra approached the experimental values,indicating the importance of structural features to dielectric properties.Furthermore,a glass additive with high matching relevance with ceramics has been developed to decrease the high sintering temperature of Mg_(0.5)Ti_(0.5)TaO_(4) ceramics,where 2–4 wt%Li_(2)O–MgO–ZnO–B_(2)O_(3)–SiO_(2)(LMZBS)glass frit was adopted to reduce the suitable temperature from 1275 to 1050℃ without significantly deteriorating the microwave dielectric characteristics.Specifically,Mg_(0.5)Ti_(0.5)TaO_(4) ceramics containing 2 wt% glass addition sintered at 1050℃for 4 h possess excellent microwave dielectric properties:dielectric constant(ε_(r))=44.3,quality factor multiplied by resonant frequency(Q×f)=23,820 GHz(f=6.2 GHz),and the temperature coefficient of resonant frequency(τ_(f))=123.2 ppm/℃.

关键词： Mg0.5Ti0.5TaO4 ceramics crystal structure low-temperature sintering

Palladium-catalysed diastereodivergent inverse- electron-demand oxa-Diels–Alder reactions of in situ formed cyclopentadienones via ligand- control

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Organic Chemistry Frontiers 2022年第5期9卷 1364-1369页

作者： xing-xing Yang xing-liang Zhao Qin Ouyang Wei Du Ying-Chun Chen Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province and Sichuan Research Center for Drug Precision Industrial TechnologyWest China School of PharmacySichuan UniversityChengdu 610041China College of Pharmacy Third Military Medical UniversityShapingbaChongqing 400038China

Here we report Pd(0)-catalysed asymmetric inverse-electron-demand oxa-Diels–Alder reactions between the carbonates of 4-hydroxy-2-cyclopentenones andα-cyano chalcones by in situ generating η^(2)-Pd(0)-cyclopentadienone complexes as HOMO-raised dienophiles,and diastereodivergent synthesis could be realised by employing a bifunctional monophosphine ligand from a chiral aminoalcohol or a proline-derived bisphosphine ligand.

关键词： inverse Palladium stereo

Dynamic Vertical Climbing Mechanism of Chinese Dragon-Li Cats Based on the Linear Inverted Pendulum Model

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Journal of Bionic Engineering 2023年第1期20卷 136-145页

作者： Qun Niu Jieliang Zhao Lulu liang Jin xing School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China

Humans have long desired but never achieved the capacity to climb walls.The fundamental reason is that human hands and feet cannot climb vertical walls like geckos and bees.Animals lacking an adhesive structure can use the body’s dynamic effect to climb walls.Here we investigated the dynamic wall climbing behavior of individuals who cannot remain stationary on the vertical wall.Taking the domestic cat as the experimental object,we constructed an experimental platform as the obstacle for the cat to climb the wall.Our research indicated that domestic cats must meet the following physical conditions to do dynamic vertical wall climbing:vertical obstacles must have nonvertical surfaces,a horizontal run-up,and contact with nonvertical surfaces before the vertical speed reduces to zero.Here we proposed a dynamic vertical wall climbing model with three contact states based on an investigation of domestic cats’dynamic wall climbing behavior and the LIP model.The motion range of the LIP model’s generalized angular coordinates varies depending on the contact state.The horizontal run-up action can improve the jumping height and obtain horizontal speed.When making contact with the vertical surface of the obstacle,the motion inertia in the horizontal direction can produce a reaction force on the contact surface,which can compensate for the influence of some gravity.This alternating contact strategy lets cats switch different initial and end contact angles.This investigation clarifies the essential process underlying animals’dynamic vertical wall climbing and establishes the theoretical foundation for the legged robot to do dynamic vertical wall climbing.

关键词： Domestic cats Dynamics Vertical climbing LIP Bionic

Hadron productions and jet substructures associated with Z^(0)/γ in Pb+Pb collisions at the LHC

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Science China(Physics,Mechanics & Astronomy) 2023年第12期66卷 77-89页

作者： Shan-liang Zhang Hongxi xing Ben-Wei Zhang Key Laboratory of Atomic and Subatomic Structure and Quantum Control(MOE) Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of MatterInstitute of Quantum MatterSouth China Normal UniversityGuangzhou 510006China Guangdong-Hong Kong Joint Laboratory of Quantum Matter Guangdong Provincial Key Laboratory of Nuclear ScienceSouthern Nuclear Science Computing CenterSouth China Normal UniversityGuangzhou 510006China Guangdong-Hong Kong Joint Laboratory of Quantum Matter Southern Nuclear Science Computing CenterSouth China Normal UniversityGuangzhou 510006China Institute of Particle Physics and Key Laboratory of Quarks and Lepton Physics(MOE) Central China Normal UniversityWuhan 430079China

We carry out a detailed study of medium modifications on Z^(0)/γ+hadron correlations as well as jet substructures in association with Z^(0)/γ in Pb+Pb collisions with √S_(NN)=5.02TeV at the LHC.We utilize the linear Boltzmann transport(LBT)model to simulate the jet-medium interactions and medium response,and an extended cluster hadronization model to investigate the nonperturbative transition of quarks and gluons into final hadrons in heavy-ion collisions.Including hadronization effect,we can well describe Z^(0)/γ+hadrons correlations and Z^(0)/γ-tagged jet substructures in both p+p and Pb+Pb collisions simultaneously.Medium modification on jet profile and jet fragmentation functions indicate that particles carrying a large fraction of the jet momentum are generally closely aligned with the jet axis,whereas low-momentum particles are observed to have a much broader angular distribution relative to jet axis in Pb+Pb collisions due to jet-medium interactions.In particular,we find that Z^(0)/γ-tagged hadron correlations are sensitive to the soft particles from the dense medium and medium response,while jet-substructures show weak dependence on those soft hadrons with only a fraction of them falling inside the jet area.

关键词： relativistic heavy-ion collisions jet quenching hadronization jet substructures