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Correlation Between Energy Transfer Rate and Atomization Energy of Some Trinitro Aromatic Explosive Molecules

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Chinese Journal of Chemical Physics 2008年第3期21卷 250-254页

作者： Su-hong Ge Xin-lu Cheng Zheng-lai Liu xiang-dong yang Fang-fang dong Department of Physics Hexi University Zhangye 734000 China Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China

An assumptive theoretical relationship is suggested to describe the property of molecular atomization energy and energy transfer rate in the initiation of explosions. To investigate the relationship between atomization energy and energy transfer rate, the number of doorway modes of explosives is estimated by the theory of Dlott and Fayer in which the rate is proportional to the number of normal mode vibrations. It was evaluated frequencies of normal mode vibrations of eight molecules by means of density functional theory （DFT） at the b3p86/6-31G（d,p） level. It is found that the number of doorway modes shows a linear correlation to the atomization energies of the molecules, which were also calculated by means of the same method. A mechanism of this correlation is discussed. It is also noted that in those explosives with similar molecular structure and molecular weight, the correlation between the atomization energy and the number of doorway modes is higher.

关键词： Secondary explosive Atomization energy Normal mode vibration Doorway region

Exponential Polynomial Approximation with Unrestricted Upper Density

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Journal of Mathematical Research and Exposition 2011年第2期31卷 353-358页

作者： xiang dong yang Department of Mathematics Kunming University of Science and Technology Yunnan 650093 P. R. China

We take a new approach to obtaining necessary and sufficient conditions for the incompleteness of exponential polynomials in L p α ,where L p α is the weighted Banach space of complex continuous functions f defined on the real axis R satisfying ＋∞ ∞ ｜f（t）｜ p e -α（t） dt） 1/p ,1 p ∞,and α（t） is a nonnegative continuous function defined on the real axis *** this paper,the upper density of the sequence which forms the exponential polynomials is not required to be *** the study of weighted polynomial approximation,consideration of the case is new.

关键词： incompleteness Banach space exponential system

Convergence of Composition Operators on Hardy-Smirnov Space

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Journal of Mathematical Research and Exposition 2011年第4期31卷 742-748页

作者： xiang dong yang Department of Mathematics Kunming University of Science and Technology Yunnan 650093 P. R. China

We consider the convergence of composition operators on Hardy-Smirnov space over a simply connected domain properly contained in the complex plane. The convergence of the power of a composition operator is also considered. Our approach is a method from Joel H. Shapiro and Wayne Smith＇s celebrated work （Journal of Functional Analysis 205 （2003） 62-89）. The resulting space is usually not the one obtained from the classical Hardy space of the unit disc by conformal mapping.

关键词： composition operators convergence Hardy-Smirnov space.

Method for Visual Localization of Oil and Gas Wellhead Based on Distance Function of Projected Features

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International Journal of Automation and computing 2017年第2期14卷 147-158页

作者： Ying Xie xiang-dong yang Zhi Liu Shu-Nan Ren Ken Chen Department of Mechanical Engineering Tsinghua University Beijing 100084 China Beijing Key Lab of Precision/Ultra-precision Manufacturing Equipments and Control Beijing 100084 China State Key Laboratory of Tribology Beijing 100084 China

A localization method based on distance function of projected features is presented to solve the accuracy reduction or failure problem due to occlusion and blurring caused by smog, when dealing with vision based localization for target oil and gas wellhead （OGWH）. Firstly, the target OGWH is modeled as a cylinder with marker, and a vector with redundant parameter is used to describe its pose. Secondly, the explicit mapping relationship between the pose vector with redundant parameter and projected features is derived. Then, a 2D-point-to-feature distance function is proposed, as well as its derivative. Finally, based on this distance function and its derivative, an algorithm is proposed to estimate the pose of target OGWH directly according to the 2D image information, and the validity of the method is verified by both synthetic data and real image experiments. The results show that this method is able to accomplish the localization in the case of occlusion and blurring, and its anti-noise ability is good especially with noise ratio of less than 70%.

关键词： Robot vision visual localization 3D object localization model based pose estimation distance function of projectedfeatures nonlinear least squares random sample consensus (RANSAC).

First-principles investigation of structural, mechanical, electronic, and bonding properties of NaZnSb

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Frontiers of physics 2015年第4期10卷 83-95页

作者： Jian-Bing Gu Chen-Ju Wang Lin Zhang Yan Cheng xiang-dong yang Laboratory for Shock Wave and Detonation Physics Research Institute of Fluid Physics Chinese Academy of Engineering Physics Mianyang 621999 China College of Physical Science and Technology Sichuan University Chengdu 610064 China Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China

The structural, mechanical, electronic, and bonding properties and phase transition of NaZnSb are explored using the generalized gradient approximation based on ab initio plane-wave pseudopotential density functional theory. With the help of the quasi-harmonic Debye model, we probe the Griineisen parameter, thermal expansivity, heat capacity, Debye temperature, and entropy of NaZnSb in tile tetragonal phase. The results indicate that the lattice constants and the bulk modulus and its first pressure derivative agree well with the available theoretical and experimental data. NaZnSb in its ground state structure exhibits a distinct energy gap of about 0.41 eV, which increases with increasing pressure. Our conclusions are consistent with the theoretical predictions obtained by the ABINIT package, but are different from those obtained through the tight-binding linear muffin-tin orbital method. As a result, further experimental and theoretical researches need to be carried out. For the purpose of providing a comparative and complementary study for future research, we first investigate the thermodynamic properties of NaZnSb.

关键词： density functional theory structural properties mechanical properties electronic properties

Interfacial Charge Transfer Induced Electronic Property Tuning of MoS_2 by Molecular Functionalization

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Chinese Physics Letters 2021年第5期38卷 94-98页

作者： Si-Han Zhou Chun-Wei Zhou xiang-dong yang yang Li Jian-Qiang Zhong Hong-Ying Mao Department of Physics Hangzhou Normal UniversityHangzhou 311121China

The modulation of electrical properties of MoS_2 has attracted extensive research interest because of its potential applications in electronic and optoelectronic ***,interfacial charge transfer induced electronic property tuning of MoS_2 are investigated by in situ ultraviolet photoelectron spectroscopy and x-ray photoelectron spectroscopy measurements.A downward band-bending of MoS_2-related electronic states along with the decreasing work function,which are induced by the electron transfer from Cs overlayers to MoS_2,is observed after the functionalization of MoS_2 with Cs,leading to n-type ***,when MoS_2 is modified with 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane(F_4-TCNQ),an upward band-bending of MoS_2-related electronic states along with the increasing work function is observed at the *** is attributed to the electron depletion within MoS_2 due to the strong electron withdrawing property of F_4-TCNQ,indicating p-type doping of MoS_*** findings reveal that surface transfer doping is an effective approach for electronic property tuning of MoS_2 and paves the way to optimize its performance in electronic and optoelectronic devices.

关键词： Interfacial Charge Transfer Induced Electronic Property Tuning of MoS_2 by Molecular Functionalization

Simulation of Melting Behavior of the MgSi03 Perovskite Under Lower Mantle Conditions

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Chinese Journal of Chemical Physics 2006年第4期19卷 311-314页

作者： Zi-jiang Liu Xiao-wei Sun xiang-dong yang Xin-lu Cheng Yun-dong Guo Institute of Electronic Information Science and Technology Lanzhou City University Lanzhou 730070 China School of Mathematics and Physics Lanzhou Jiaotong University Lanzhou 730070 China Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China

The melting curve of MgSiO3 perovskite was simulated using molecular dynamics method combining with the effective pair potentials under the lower mantle conditions. It was shown that the state equation simulated for MgSiO3 perovskite is very successful in reproducing accurately the experimental data over a wide range of pressure. The pressure dependence of the simulated melting temperature of MgSiO3 perovskite is in agreement with the recent experimental data. The melting curve simulated for MgSiO3 is very steep at pressures below 60 GPa first, then it becomes smooth with increasing pressure. At the core mantle boundary pressure 135 GPa, MgSiO3 perovskite melts at 6500 K, which is significantly lower than that of the extrapolations of the experimental data from Zerr and Boehler.

关键词： Melting curve Molecular dynamics High pressure MgSiO3

Coordination for a Closed-loop Supply Chain with Recycling Platform Considering Dynamic Setting

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Journal of Systems Science and Systems Engineering 2024年第4期33卷 425-451页

作者： Zehua xiang Ting Ji Lingfeng dong School of Management Zhejiang UniversityHangzhou310058China School of Business Hangzhou City UniversityHangzhou310015China Alibaba Business College Hangzhou Normal UniversityHangzhou311121China

This paper presents a dynamic closed-loop supply chain(CLSC)model,incorporating a manufacturer,a retailer,and an internet recycling platform(IRP),utilizing differential game theory while considering the forgetting effect of *** model encompasses factors such as the quality level of used products and Big Data marketing(BDM),comparing optimal equilibriums under decentralized and cooperative decision *** effectively coordinate the dynamic CLSC at each time point,we propose a revenue-sharing and cost-sharing(RSCS)combined *** addition to ensuring reasonable sharing of revenues and costs,this contract allows the manufacturer to flexibly adjust wholesale prices for final products and transfer prices for used products in order to distribute profits appropriately and achieve Pareto optimality within the CLSC ***,our results indicate that there exists a threshold for Big Data marketing efficiency;high-efficiency BDM not only facilitates increased recycling on Internet platforms but also reduces unit recycling costs for ***,when implementing the combined contract,Big Data marketing efficiency does not impact the transfer price paid by manufacturers to Internet recycling platforms.

关键词： Big Data marketing differential game closed-loop supply chain coordination internet recycling platform

Real-time in-situ monitoring of chiral changes during a reaction at single-molecule level

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Science China Chemistry 2024年第2期67卷 422-423页

作者： Min Tan dong xiang Institute of Modern Optics and Center of Single-Molecule Science Tianjin Key Laboratory of Micro-scale Optical Information Science and TechnologyNankai UniversityTianjin300350China School of Materials Science and Engineering Smart Sensing Interdisciplinary Science CenterNankai UniversityTianjin300350China TongLu FeiRan Garment–Nankai University Joint Laboratory Nankai UniversityTianjin300350China

Molecular chirality is a widespread phenomenon in nature,playing a critical role in various fields such as chemistry [1],life sciences [2], and materials science [3], and has therefore attracted significant attention and research by scholars [4–6].However, the chirality in chemical reactions is often dynamic, making real-time monitoring of chiral changes during chemical reactions at the single-molecule level extremely challenging.

关键词： chiral chirality critical