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Gravidynamics,spinodynamics and electrodynamics within the framework of gravitational quantum field theory

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Science China(Physics,Mechanics & Astronomy) 2023年第6期66卷 148-190页

作者： Yue-liang Wu International Centre for Theoretical Physics Asia-Pacific University of Chinese Academy of SciencesBeijing 100190China Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190China Taiji Laboratory for Gravitational Wave Universe(Beijing/Hangzhou) University of Chinese Academy of SciencesBejing 100049China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou310024China

By noticing the fact that the charged leptons and quarks in the standard model are chirality-based Dirac spinors since their weak interaction violates maximally parity symmetry though they behave as Dirac fermions in electromagnetic interaction,we show that such a chirality-based Dirac spinor possesses not only electric charge gauge symmetry U(1)but also inhomogeneous spin gauge symmetry WS(1,3)=SP(1,3)?W1,3,which reveals the nature of gravity and *** gravitational force and spin gauge force are governed by the gauge symmetries W1,3and SP(1,3),respectively,and a biframe spacetime with globally fiat Minkowski spacetime as base spacetime and locally fiat gravigauge spacetime as a fiber is described by the gravigauge field through emergent non-commutative *** gauge-geometry duality and renormalizability in gravitational quantum field theory(GQFT)are carefully discussed.A detailed analysis and systematic investigation on gravidynamics and spinodynamics as well as electrodynamics are carried out within the framework of GQFT.A full discussion on the generalized Dirac equation and Maxwell equation as well as Einstein equation and spin gauge equation is made in biframe *** effects of gravidynamics as extension of general relativity are particularly *** dynamic equations of basic fields are demonstrated to preserve the spin gauge covariance and general coordinate covariance due to the spin gauge symmetry and emergent general linear group symmetry GL(1,3,R),so they hold naturally in any spinning reference frame and motional reference frame.

关键词： inhomogeneous spin gauge symmetry locally flat gravigauge spacetime gravitational relativistic quantum mechanics with generalized Dirac equation gravidynamics with generalized Einstein equation generalized Maxwell equation in any motional and spinning reference frame

Formula of Overtopping Discharge of Vertical Seawall with A Form Similar to Solitary Wave Function

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China Ocean Engineering 2022年第5期36卷 802-807页

作者： LI Xiao-liang School of Naval Architecture&Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

An empirical formula to predict overtopping discharge of vertical wall is presented,in which an expression similar to the solitary wave function is proposed to describe the rule of the influence of relative water *** formula is derived from performing an investigation to the well-known overtopping graphs of Goda,and for the sake of interest,the process of the derivation is *** make clear the formula’s performance,relevant test datasets in the CLASH database are extracted to examine the error levels of the *** a result,an overall good agreement has been found between the predictions of the formula and the extracted datasets in a wide range outside the extreme shallow region,i.e.,the range of relative water depth smaller than 0.6,in which the water depth near the wall is so shallow that nearly all the incoming waves have been broken before reaching the wall.

关键词： overtopping discharge formula vertical wall Goda graph

Long-Range Ordered Nanostructures of Assembling Macromolecules via Rational Design of Kinetic Pathways:A Computational Perspective

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Chinese Journal of Polymer Science 2023年第9期41卷 1318-1328,I0004页

作者： liang-Shun Zhang Shanghai Key Laboratory of Advanced Polymeric Materials School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai200237China

Designing the kinetic pathways of assembling macromolecules such as block copolymers and DNA strands is crucial not only for an achievement of thermodynamically equilibrium nanostructures over macroscopic areas,but also for a better understanding of formation process of higher-level superstructures where well-tailored assemblies act as mesoscopic building *** analysis and computer simulations provide excellent opportunities to microscopically reveal the kinetics and mechanism of structural evolution as well as the collective behaviors of building *** this perspective,we summarize our efforts of theoretical and computational modelling to understand the long-range ordering mechanisms and the organization kinetics of assembling macromolecules along designable ***,we present the computational modelling and recent strategies of designable pathways for the achievement of long-range ***,from the computational views,we give the applications of pathway-designed strategies to explore the ordering mechanism and kinetics in the course of structural evolution,covering the block copolymers and their nanocomposites under zone annealing as well as the hierarchical self-assembly of mesoscopic building units(e.g.,patchy micelles and DNA-functionalized nanoparticles).Finally,we outlook future directions in the field of designable pathways for the achievement of long-range ordered *** perspective could promote further efforts towards the wide applications of theoretical and computational modelling in the construction of soft hybrid metamaterials.

关键词： Dynamic self-consistent field theory Structural evolution Block copolymers Hierarchical self-assembly Polymerization

DEPENDENCE BETWEEN STOCK RETURNS AND INVESTOR SENTIMENT IN CHINESE MARKETS:A COPULA APPROACH

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Journal of Systems Science & Complexity 2012年第3期25卷 529-548页

作者： Xunfa LU Kin Keung LAI liang liang Department of Management Sciences City University of Hong KongHong KongChina School of Business University of Science and Technology of China

Using data of newly opened stock trading accounts in China as a proxy of investor sentiment index, the authors employ the time-varying copula-GARCH model with Hansen＇s skewed Student-t innovations to investigate the dynamic dependence between investor sentiment and stock returns. The empirical findings show that shifts in investor sentiment are asymptotically positively correlated to stock returns in extreme value situations in both A shares market and B shares market in China, that is to say, stock prices will increase （decrease） more when investors become more bullish （bearish）. Also, results show that the dependence between investor sentiment and stock returns is time-varying, which means that the traditional Pearson＇s correlation based on normal distribution is not enough to describe the relationship between stock market behavior and investor behavior.

关键词： Behavioral finance copula GARCH investor sentiment newly opened stock trading accounts.

Oxygen Availability Affects Behavioural Thermoregulation of Turtle Embryos

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Asian Herpetological Research 2023年第4期14卷 257-260页

作者： liang liang Weiguo DU Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China

Extending recent findings that reptile embryos seek optimal temperatures inside eggs for thermoregulation,our study demonstrates that this thermoregulatory behaviour can be affected by the amount of oxygen available to an *** exposed embryos of a freshwater turtle(Mauremys reevesii)to two heat sources(an optimal temperature of 30°C and a high temperature of 33°C)under three different oxygen levels–hypoxia(12%O2),normoxia(21%O2)and hyperoxia(30%O2)–and quantified the interactive effects of temperature and oxygen availability on embryonic thermoregulatory *** results demonstrated that,in both thermal treatments,embryos exposed to hypoxia did not move as close to the heat source and therefore selected lower temperatures than those exposed to normoxia or *** may select low temperatures under hypoxic conditions to decrease oxygen consumption and therefore alleviate the negative impact of hypoxic stress.

关键词： behavioural thermoregulation embryonic development heat tolerance hypoxia reptile

Growth Mechanism and Characterization of Single-crystalline Ga-doped SnO2 Nanowires and Self-organized SnO2/Ga2O3 Heterogeneous Microcomb Structures

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Chinese Journal of Chemical Physics 2008年第2期21卷 181-186页

作者： Yong Su liang Xu Xue-mei liang Yi-qing Chen School of Materials Science and Engineering Hefei University of Technology Hefei 230009 China Hefei General Machinery Research Institute Hefei 230031 China

Single-crystalline Ga-doped SnO2 nanowires and SnO2：Ga2O3 heterogeneous microcombs were synthesized by a simple one-step thermal evaporation and condensation method. They were characterized by means of X-ray powder diffraction （XRD）, field-emission scanning electron microscopy （FE-SEM）, energy-dispersive X-ray spectroscopy （EDS）, transmission electron microscopy （TEM） and selected-area electron diffraction （SAED）. FE-SEM images showed that the products consisted of nanowires and mierocombs that represent a novel morphology. XRD, SAED and EDS indicated that they were single-crystalline tetragonal SnO2. The influence of experimental conditions on the morphologies of the products is discussed. The morphology of the product showed a ribbon-like stem and nanoribbon array aligned evenly along one or both side of the nanoribbon. It was found that many Ga2O3 nanoparticles deposited on the surface of the microcombs. The major core nanoribbon grew mainly along the [110] direction and the self-organized branching nanoribbons grew epitaxially along [110] or [110] orientation from the （110） plane of the stem. A growth process was proposed for interpreting the growth of these remarkable SnO2：Ga2O3 heterogeneous microcombs. Due to the heavy doping of Ga, the emission peak in photoluminescence spectra has red-shifted as well as broadened significantly.

关键词： Microcomb Nanoribbon Photoluminescence

Electro-derived Cu-Cu2O nanocluster from LDH for stable and selective C2 hydrocarbons production from CO2 electrochemical reduction

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Journal of Energy Chemistry 2020年第9期29卷 169-180,I0005页

作者： Naveed Altaf Shuyu liang liang Huang Qiang Wang College of Environmental Science and Engineering Beijing Forestry UniversityBeijing 100083China

Recently,CO2 conversion by electrochemical tool into value-added chemicals has been considered as one of the most promising strategies to offer sustainable development in energy and *** this contribution,we investigated electro-derived composites from Cu-based layered double hydroxide(LDH)for CO2 electrochemical *** Cu-Cu2O based nanocomposite(HPR-LDH)were derived by using electro-strategy from LDH having the stability up to 20 h and selectivity toward C2H4 with faraday efficiency up to 36%by significantly suppressing CH4 and H2 with respect to bulk Cu foil.A highly negative reduction potential derived catalyst(HPR-LDH)maintained long-term stability for the selective production of ethylene over methane,and a small amount of Cu2O was still observed on the catalyst surface after CO2 reduction reaction(CO2RR).Moreover,such unique strategy for electro-derived composite from LDH having small nanoparticles stacked each other grown on layered structure,would provide new insight to improve durability of O-Cu combination catalysts for C-C coupling products during electrochemical CO2conversion by suppressing *** XRD,SEM,ESR,and XPS analyses confirmed that the long-term ethylene selectivity of HPR-LDH is due to the presence of subsurface *** designed composite catalyst significantly enhances the stability and selectivity,and also decreases the over potential for CO2 *** predict that the new designed LDH 2D-derived composites may attract new insight for transition metal and may open up a new direction for known structural properties of selective catalyst synthesis regarding effective CO2 reduction reaction.

关键词： Electrochemical Electro-derived strategy Layered double hydroxide Ethylene Cu2O nanocomposites

Measuring Environmental Performance of Provincial Thermal Power Plants in China:A Malmquist DEA Approach with Fixed-Sum Undesirable Outputs

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Journal of Systems Science & Complexity 2022年第4期35卷 1201-1224页

作者： HOU Wenhui ZHENG Yunwen liang liang LI Yongjun School of Management University of Science and Technology of ChinaHefei230026China

With the development of China’s economy,environmental pollution has become cumulatively *** primary source of environmental pollution is thermal power generation,which has attracted the attention of governments and academia in recent *** effectively reduce environmental pollution,research should study how to constrain the undesirable output of thermal power plants,that is,to limit the total undesirable output of the plants to a certain fixed ***,few studies have suggested that these undesirable outputs should be fixed-sum ***,no previous research publication about thermal power plants has analyzed their environmental performance *** address these gaps,a novel Malmquist-DEA approach is proposed for evaluate the environmental performance of thermal power plants in this *** approach generalizes the equilibrium efficient frontier DEA model with fixed-sum undesirable outputs and incorporates the model into the Malmquist productivity index(MPI).The authors apply this approach to the analysis of provincial thermal power plant environmental performance in China and analyze such plants’trends based on panel data from2011 to *** empirical research shows that the environmental performance of regional thermal power plants was positively affected by efficiency change and negatively affected by technical ***,the authors provide policy suggestions based on our findings.

关键词： Data envelopment analysis environmental performance fixed-sum undesirable outputs Malmquist productivity index thermal power plants

A Fractional Orlicz–Sobolev Poincaré Inequality in John Domains

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Acta Mathematica Sinica,English Series 2021年第6期37卷 854-872页

作者： Tian liang Department of Mathematics Beihang UniversityBeijing 100191P.R.China

Let n≥2,β∈(0,n)andΩ■R^(n) be a bounded *** thatφ:[0,∞)→[0,∞)is a Young function which is doubling and satisfies sup x>0∫^(1)_(0)φ(tx)/φ(x)dt/t^(β+1)<∞.If Ω is a John domain,then we show that it supports a(φ^(n/(n-β)),φ)_(β)-Poincaré***,assume thatΩis simply connected domain when n=2 or a bounded domain which is quasiconformally equivalent to some uniform domain when n≥***Ωsupports a((φ^(n/(n-β)),φ)β-Poincaréinequality,then we show that it is a John domain.

关键词： Intrinsic fractional Orlicz-Sobolev John domains