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Long-range asymmetric Cherenkov radiation

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 170-171页

作者： gang zhong Qingdong Ou Macao Institute of Materials Science and Engineering(MIMSE) Faculty of Innovation EngineeringMacao University of Science and TechnologyTaipaMacao 999078China

Cherenkov radiation(CR)is gaining increasing attention as a high-output power Terahertz radiation source,and it plays a significant role in particle detectors,accelerators,and space science[1].This captivating phenomenon was first observed by Cerenkov in 1934 and was later explained theoretically by Tamm and Frank in 1937,earning them the Nobel Prize in Physics in *** occurs when charged particles move faster than the phase velocity of light in a specific medium.

关键词： asymmetric faster explained

α-clustering effect on flows of direct photons in heavy-ion collisions

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Nuclear Science and Techniques 2021年第6期32卷 122-132页

作者： Chen-zhong Shi Yu-gang Ma Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China University of the Chinese Academy of Sciences Beijing 100080China

In this study,we reconstruct theγ-photon energy spectrum,which is in good agreement with the experimental data of ^(86)Kr+^(12)C at E/A=44 Me V within the framework of the modified EQMD *** directed and elliptic flows of free protons and direct photons were investigated by considering theα-clustering structure of ^(12)*** with free protons,direct photon flows provide clearer information about the early stage of a nuclear *** difference in the collective flows between different configurations of ^(12)C is observed in this *** indicates that the collective flows of direct photons are sensitive to the initial ***,theγbremsstrahlung process might be taken as an alternative probe to investigate theα-clustering structure in a light nucleus from heavy-ion collisions within the Fermienergy region.

关键词： Nuclear reaction Direct photon Collective flow α-clustering configuration

Theoretical Studies on the Isomerization of Peroxynitrite to Nitrate Mediated by Peroxynitrous Acid

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Chinese Journal of Structural Chemistry 2008年第2期27卷 171-176页

作者： LIU Yong-Dong zhong Ru-gang College of Life Science ＆ Bioengineering Beijing University of Technology Beijing 100022 China

The conversion of peroxynitrite （ONOO-） to nitrate （NO3-） mediated by peroxynitrous acid （ONOOH） has been investigated at the CCSD/6-311G（d）//B3LYP/6-31 1＋G（d,p） level. Two kinds of pathways for the title reaction were found. The results show that the energy barrier of isomerization through pathway 1 is around 25 kcal/mol in the gas phase. This value is significantly lower than that of isomerization without any catalysts. Thus, it indicates that ONOOH definitely makes the conversion from ONOO- to NO3- feasible. Although pathway 2 does not decrease the energy barrier of this isomerization, peroxynitric acid （O2NOOH） was obtained; moreover, this is a new pathway for this formation. In view of the results that peroxynitrate anion can decompose into nitrite and dioxygen, we conclude that our results are consistent with the experimental observation that nitrate, nitrite, and dioxygen are the main final products of the decay of peroxynitrite around pH 7.

关键词： peroxynitrite peroxynitrous acid isomerization DFT

Recent Advances in Nickel Catalyzed Carbonylative Reactions via the Insertion of Carbon Monoxide

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Chinese Journal of Chemistry 2024年第2期42卷 177-189页

作者： Xinzhou Chen gang Chen zhong Lian Department of Dermatology State Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan UniversityChengduSichuan 610041China

Carbonyl compounds have attracted considerable attention due to their extensive applications in drug ***,they are important synthetic intermediates for the construction of carbon-carbon and carbon-heteroatom ***-metal-catalyzed carbonylation via the insertion of co is one of the most efficient and straightforward strategies to access carbonyl ***,most of the transition-metal-catalyzed carbonylative reactions require expensive and toxic noble-metal ***,there is a growing demand for the exploration of nickel-catalyzed carbonylative reactions via the insertion of CO due to the earth abundance and low cost of *** with the well-established palladium-catalyzed carbonylative reactions,nickel-catalyzed analogous transformations have been relatively *** is primarily because CO strongly binds to nickel,often resulting in catalyst *** recent years,some research groups have focused on using CO surrogates or NN_(2) pincer nickel catalyst to circumvent the formation of Ni(CO)_(4).Nickel-catalyzed carbonylation has been applied in the construction of carbonyl-containing compounds,such as ketones,carboxylic acids,thioesters,acyl chloride and carboxamides.

关键词： Carbonylation Nickel catalysis Carbon monoxide C1 chemistry Carbonyl-containing compounds

An iterative algorithm for analysis of coupled structural-acoustic systems subject to random excitations

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Acta Mechanica Sinica 2012年第2期28卷 458-467页

作者： Guo-zhong Zhao gang Chen Zhan Kang State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology116024 DalianChina

This paper analyzes the random response of structural-acoustic coupled systems. Most existing works on coupled structural-acoustic analysis are limited to systems under deterministic excitations due to high computational cost required by a random response analysis. To reduce the computational burden involved in the coupled random analysis, an iterative procedure based on the Pseudo excitation method has been developed. It is found that this algorithm has an overwhelming advantage in computing efficiency over traditional methods, as demonstrated by some numerical examples given in this paper.

关键词： Random excitation Coupled structural-acoustic systems Pseudo excitation method

Water Storage of Water-Based Enhanced Geothermal System Based on a 3D Thermal-Hydrologic-Mechanical Model

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Journal of Thermal Science 2022年第3期31卷 946-957页

作者： WANG Changlong HUANG Xinjie TANG gang zhong Dan School of Civil Engineering and Architecture Anhui University of TechnologyMa’anshan243002China Zhuhai Da Hengqin Science and Technology Development Co. LtdZhuhai519000China School of Safety Engineering China University of Mining and TechnologyXuzhou221116China

The thermal-hydrologic-mechanical(THM)coupled processes in water-based enhanced geothermal system(EGS)greatly influence the heat extraction performance of *** THM models have been proposed,however,there is a lack of detailed analysis of water storage,which is caused by the increments of reservoir porosity and water density,and the influence of water storage on the heat extraction performance needs to be *** this paper,a 3D THM model is established to simulate the water storage amount and heat extraction rate for a water-based *** 3D THM model is verified against an analytical ***,the influences of water storage are investigated,and comparisons between the THM and thermal-hydrologic(TH)processes are made for different initial reservoir *** results show that the increment of reservoir porosity has a larger influence on water storage than that of water *** ignoring water storage,the injection flow rate would be underestimated,while the production flow rate and heat extraction rate would be overestimated,and the reservoir would be cooled a little *** with the TH processes,the THM processes show larger cumulative water storage amount,higher steady-state heat extraction rate and higher cooling rate of reservoir,indicating that mechanical process has important influences on EGS *** higher initial reservoir porosity,the cumulative water storage amount is *** can be inferred that the water storage amount is related to the cooling rate of *** results of this paper show that water storage has a certain influence on the heat extraction rate,and that the mechanical process and initial reservoir porosity have important effects on the water storage amount,which should be simulated based on a THM model.

关键词： enhanced geothermal system thermal-hydrologic-mechanical model heat extraction water storage

Nutational Oscillatory Effect of the Test Body in Space Equivalence Principle Experiments

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Communications in Theoretical Physics 2004年第2期41卷 211-214页

作者： SHAOCheng-gang ZHANGYuan-zhong LUOjun DepartmentofPhysics HuazhongUniversityofScienceandTechnologyWuhan430074China InstituteofTheoreticalPhysics theChineseAcademyofSeuebcesP.O.Box2735Beijing100080China

The significance of quadrupole gravitational force is discussed for test mass in equivalence principle (EP), and the angular moment acting on a cylindrically symmetrical body due to quadrupole force is calculated, which will result in nutational oscillatory effect. The oscillations contain a perturbation with the same frequency of EP violation signal, which is mitigated by two different methods as in Galileo Galilei (GG) mission and μSCOPE. In GG the sensor for readout is sensitive to differential forces in the orbital plane perpendicular to spin axis of test cylinders. In order to mitigate the nutational oscillatory effect, test mass should be rapidly rotated with the spin axis. However, in μSCOPE, the readout sensitive axis is the symmetry axis in the orbital plane. This nutational oscillation will produce a second order effect in the rotation amplitude at twice the signal frequency, and could be subtracted easily, too.

关键词： equivalence principle

The Generalized West Decomposition of Operators and Other Compact Perturbation Problems

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Acta Mathematica Sinica,English Series 2006年第2期22卷 515-522页

作者： Wei gang SU Huai Jie zhong School of Mathematics and Computer Science Fujian Normal University

This paper introduces the concept of the generalized Riesz operators and the concept of the generalized West decomposition of a general operator which generalizes the definition of the West decomposition of Riesz operators, and proves that the following three statements are equivalent on a general Banach space：（a） Every generalized Riesz operator has the generalized West decomposition; （b） Every operator makes strong Stampfli theorem true; Every operator has Apostol＇s compact correction.

关键词： correction Banach space generalized Riesz operator generalized West decomposition compact

Synchronized Firing in Coupled Inhomogeneous Excitable Neurons

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Communications in Theoretical Physics 2002年第10期38卷 415-420页

作者： ZHENG Zhi-gang WANG Fu-zhong Department of Physics Beijing Normal University Beijing 100875 China Department of Physics Jinzhou Teachers College Jinzhou 121003 Liaoning Province China Department of Physics Jinzhou Teachers College Jinzhou 121003 Liaoning Province China

We study the firing synchronization behavior of the inhomogeneous excitable media. Phase synchronizationof neuron firings is observed with increasing the coupling, while the phases of neurons are different (out-of-phase synchronization). We found the synchronization of bursts can be greatly enhanced by applying an external forcing (in-phasesynchronization). The external forcing can be either a periodic or just homogeneous thermal noise. The mechanismresponsible for this enhancement is *** numbers: 05.45.-a, 87.10.

关键词： excitable media, phase synchronization, FitzHugh-Nagumo model