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Stereocomplex Crystallization in Asymmetric Diblock Copolymers Studied by Dynamic monte carlo simulations

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Chinese Journal of Polymer Science 2021年第5期39卷 632-639,I0008页

作者： Ying Xu Jun Yang Zong-Fa Liu Zhi-Ping Zhou Zhao-Peng Liang Tong-Fan Hao Yi-Jing Nie Research School of Polymeric Materials School of Materials Science and EngineeringJiangsu UniversityZhenjiang 212013China Institute of Green Chemistry and Chemical Technology Jiangsu UniversityZhenjiang 212013China

Stereocomplex crystallization in asymmetric diblock copolymers was studied using dynamic monte carlo simulations,and the key factor dominating the formation of stereocomplex crystallites(SCs)was *** asymmetric diblock copolymers with higher degree of asymmetry exhibit larger difference between volume fractions of beads of different blocks,and local miscibility between different kinds of beads is lower,leading to lower SC *** minimize the interference from volume fraction of beads,the SC formation in blends of asymmetric diblock copolymers was also *** the cases where the volume fractions of beads of different blocks are the same,similar local miscibility between beads of different blocks and similar SC content was *** findings indicate that the volume fraction of beads of different blocks is a key factor controlling the SC formation in the asymmetric diblock *** SC content can be regulated by adjusting the difference between the contents of beads of different blocks in asymmetric diblock copolymers.

关键词： Asymmetric diblock copolymers monte carlo simulations Stereocomplex crystallization

Kinetic monte carlo simulations of three-dimensional self-assembled quantum dot islands

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Chinese Physics B 2014年第1期23卷 330-335页

作者：宋鑫冯昊刘玉敏俞重远尹昊智 State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications

By three-dimensional kinetic monte carlo simulations, the effects of the temperature, the flux rate, the total coverage and the interruption time on the distribution and the number of self-assembled InAs/GaAs （001） quantum dot （QD） islands are studied, which shows that a higher temperature, a lower flux rate and a longer growth time correspond to a better island distribution. The relations between the number of islands and the temperature and the flux rate are also successfully simulated. It is observed that for the total coverage lower than 0.5 ML, the number of islands decreases with the temperature increasing and other growth parameters fixed and the number of islands increases with the flux rate increasing when the deposition is lower than 0.6 ML and the other parameters are fixed.

关键词： monte carlo simulations self-assembled quantum dot islands growth parameters

Phase equilibrium of Cd_(1-x)Zn_xS alloys studied by first-principles calculations and monte carlo simulations

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Chinese Physics B 2016年第1期25卷 549-555页

作者：张付珍薛红涛汤富领李小康路文江冯煜东 State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Department of Materials Science and EngineeringLanzhou University of TechnologyLanzhou 730050China Science and Technology on Surface Engineering Laboratory Lanzhou Institute of PhysicsLanzhou 730000China

The first-principles calculations based on density functional theory combined with cluster expansion techniques and monte carlo （MC） simulations were used to study the phase diagrams of both wurtzite （WZ） and zinc-blende （ZB） Cdl_xZnxS alloys. All formation energies are positive for WZ and ZB Cdl-xZnxS alloys, which means that the Cdl-xZnxS alloys are unstable and have a tendency to phase separation. For WZ and ZB Cdl_xZnxS alloys, the consolute temperatures are 655 K and 604 K, respectively, and they both have an asymmetric miscibility gap. We obtained the spatial distributions of Cd and Zn atoms in WZ and ZB *** alloys at different temperatures by MC simulations. We found that both WZ and ZB phases of *** alloy exhibit phase segregation of Cd and Zn atoms at low temperature, which is consistent with the phase diagrams.

关键词： first-principles calculation monte carlo simulations phase separation spatial distribution

Magnetic properties of La2CuMnO6 double perovskite ceramic investigated by monte carlo simulations

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Chinese Physics B 2020年第5期29卷 387-391页

作者： S Mtougui I EL Housni N EL Mekkaoui S Ziti S Idrissi H Labrim R Khalladi L Bahmad Laboratoire de la Matière Condensée et des Sciences Interdisciplinaires (LaMCScI) Mohammed V University of RabatFaculty of SciencesB.P.1014 RabatMorocco Intelligent Processing and Security Systems Mohammed V University of RabatFaculty of SciencesB.P.1014 RabatMorocco USM/DERS/Centre National de l’Energie des Sciences et des Techniques Nucl´eaires(CNESTEN)RabatMorocco

We present a theoretical study of the magnetic properties of the lanthanum copper manganate double perovskite La2CuMnO6 ceramic,using monte carlo *** analyze and discuss the ground state phase diagrams in different planes to show the effect of every physical *** on the monte carlo simulations,which combine Metropolis algorithm and Ising model,we explore the thermal behavior of the total magnetization and *** also present and discuss the influence of physical parameters such as the external magnetic field,the exchange coupling interactions between magnetic atoms,and the exchange magnetic field on the magnetization of the ***,the critical temperature of the system is about Tc=70 K,in agreement with the experimental ***,the hysteresis loops of La2CuMnO6 are discussed.

关键词： double perovskite La2CuMnO6 monte carlo simulations Ising model hysteresis loops Metropolis algorithm critical temperature

Physical design and monte carlo simulations of a space radiation detector onboard the SJ-10 satellite

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Chinese Physics C 2015年第1期39卷 54-59页

作者：刘雅清王焕玉崔兴柱彭文溪樊瑞睿梁晓华高旻张云龙张承模张家宇杨家卫汪锦州张飞董亦凡郭东亚周大卫 Institute of High Energy Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Jilin University

A radiation gene box （RGB） onboard the S J-10 satellite is a device carrying mice and drosophila cells to determine the biological effects of space radiation environment. The shielded fluxes of different radioactive sources were calculated and the linear energy transfers of γ-rays, electrons, protons and α-particles in the tissue were acquired using A-150 tissue-equivalent plastic. Then, a conceptutual model of a space radiation instrument employing three semiconductor sub-detectors for deriving the charged and uncharged radiation environment of the RGB was designed. The energy depositions in the three sub-detectors were classified into 15 channels （bins） in an algorithm derived from the monte carlo method. The physical feasibility of the conceptual instrument was also verified by monte carlo simulations.

关键词： particle detecting space radiation detector design monte carlo simulations

Dynamic magnetic behaviors and magnetocaloric effect of the Kagome lattice:monte carlo simulations

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Communications in Theoretical Physics 2023年第7期75卷 155-168页

作者： Wei-Chen Wu Kai-Le Shi Wei Jiang School of Science Shenyang University of TechnologyShenyang 110870China School of Environmental and Chemical Engineering Shenyang University of TechnologyShenyang 110870China School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

Based on the monte carlo method,we examined the dynamic magnetic behaviors and magnetocaloric effect of a Kagome lattice subjected to the influence of time-dependent oscillating and time-independent magnetic *** used the Ising model to describe the Kagome lattice and study the dynamic order parameters,blocking temperature,internal energy,and phase *** results revealed that exchange coupling increases the stability of the system and the bias field induces order;however,the time-dependent oscillating magnetic field induces *** addition,the magnetocaloric properties,changes in magnetic entropy,and relative cooling power of the Kagome lattice were investigated.

关键词： magnetocaloric dynamic order parameter Kagome lattice phase diagrams monte carlo simulations

monte carlo simulations OF REVERSIBLE MELTING ON THE FOLD-END SURFACES OF POLYMER LAMELLAR CRYSTALS

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MONTE CARLO SIMULATIONS OF REVERSIBLE MELTING ON THE FOLD-EN...

95 GeV light Higgs in the top-pair-associated diphoton channel at the LHC in the minimal dilaton model

5th International Symposium on Engineering Plastics

作者： Xiaoming JIANG Wenbing HU~* Department of Polymer Science and Engineering School of Chemistry and Chemical Engineering Nanjing University 210093 Nanjing China

＜正＞Reversible melting process exists at the fold-end surfaces of polymer lamellar crystals[1].This process has been evidenced by both experiments[2]and molecular simulations[3].However,the expected association between this process and the chain mobility requires further *** we performed dynamic monte carlo simulations of a polymer lamellar crystal in 3D lattice box with periodic boundary *** using saw-tooth-type temperature modulation upon the quasi-isothermal annealing,the internal energy of the crystal appears as a periodic response corresponding to the modulated temperatures,as shown in Fig *** chose the data analysis method without Fourier transformation,which was proposed by Hu et al.[4],to calculate the reversing heat capacity from the internal energy *** observed that the reversing heat capacity originates from the reversible melting process at the fold-end *** lower chain-sliding mobility in the lamellar crystal,the reversing heat capacity decreases,as shown in Fig *** result evidences the association between the reversible melting and the chain *** addition,with the increase of the modulated frequency,the reversing heat capacity exhibits a declining tendency,as shown in Fig *** result implies a competition between chain relaxation and temperature modulation.

关键词： Lamellar crystal monte carlo simulations Temperature modulated DSC Reversible melting

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Chinese Physics C 2024年第7期48卷 75-83页

作者：王坤朱经亚 College of Science University of Shanghai for Science and TechnologyShanghai 200093China School of Physics and Electronics Henan UniversityKaifeng 475004China

Motivated by experimental hints and theoretical frameworks indicating the existence of an extended Higgs sector,we explore the feasibility of detecting a 95 GeV light Higgs boson decaying into a diphoton within the minimal dilaton model at the 14 TeV ***,we identify the correlations between the production cross section,decay branching ratios,and model parameters,e.g.,the scalar mixing angle■Subsequently,we utilize monte carlo simulations to generate the signal of the light Higgs boson via the■process,along with the corresponding *** effectively separate the signal from the dominant backgrounds■,we employ a meticulous cut-based selection ***,we find that with an integrated luminosity of■,the regions of■can be covered over the3σlevel.

关键词： 95 GeV light Higgs minimal dilaton model monte carlo simulations LHC diphoton decay channel

A comparison of model choice strategies for logistic regression

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Journal of Data and Information Science 2024年第1期9卷 37-52页

作者： Markku Karhunen Built Environment Solutions unit Finnish Environment Institute(Syke)Latokartanonkaari 1100790 HelsinkiFinland

Purpose:The purpose of this study is to develop and compare model choice strategies in context of logistic *** choice means the choice of the covariates to be included in the ***/methodology/approach:The study is based on monte carlo *** methods are compared in terms of three measures of accuracy:specificity and two kinds of sensitivity.A loss function combining sensitivity and specificity is introduced and used for a final ***:The choice of method depends on how much the users emphasize sensitivity against *** also depends on the sample *** a typical logistic regression setting with a moderate sample size and a small to moderate effect size,either BIC,BICc or Lasso seems to be *** limitations:Numerical simulations cannot cover the whole range of data-generating processes occurring with real-world ***,more simulations are *** implications:Researchers can refer to these results if they believe that their data-generating process is somewhat similar to some of the scenarios presented in this ***,they could run their own simulations and calculate the loss ***/value:This is a systematic comparison of model choice algorithms and heuristics in context of logistic *** distinction between two types of sensitivity and a comparison based on a loss function are methodological novelties.

关键词： Model choice Logistic regression Logit regression monte carlo simulations Sensitivity Specificity