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A survey of dark matter and related topics in cosmology

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Frontiers of physics 2017年第2期12卷 1-219,F0004页

作者： bing-lin Young Department of Physics and Astronomy Iowa State University Ames IA 50011 USA

This article presents an extensive review of the status of the search of the dark matter. The first eight sections are devoted to topics in dark matter and its experimental searches, and the rest to selected topics in astrophysics and cosmology, which are intended to supply some of the needed background for students in particle physics. Sections 9 and 13 are introductory cosmology. The three astrophysical topics, Big Bang nucleosynthesis Section 10, Boltzmann transport equation and freeze out of massive particles Section 11, and CMB anisotropy Section 12 can all be studied in analytical approaches when reasonable approximations are made. Their original analytically forms, to which this article follows very closely, were given by particle physicists. Dark matter is an evolving subject requiring timely update to stay current. Hence a review of such a subject matter would undoubtedly have something wanting when it appears in print. It is hoped that this review can form a humble basis for those graduate students who would like to pursue the subject of dark matter. The reader can use the extensive table of contents to see in some details the materials covered in the article.

关键词： dark matter CMB anisotropy Boltzmann transport equation freeze out of massive particles

Connes distance of 2D harmonic oscillators in quantum phase space

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Chinese Physics B 2021年第11期30卷 170-179页

作者： bing-Sheng lin Tai-Hua Heng School of Mathematics South China University of TechnologyGuangzhou 510641China Laboratory of Quantum Science and Engineering South China University of TechnologyGuangzhou 510641China School of Physics and Material Science Anhui UniversityHefei 230601China

We study the Connes distance of quantum states of two-dimensional(2D)harmonic oscillators in phase *** the Hilbert–Schmidt operatorial formulation,we construct a boson Fock space and a quantum Hilbert space,and obtain the Dirac operator and a spectral triple corresponding to a four-dimensional(4D)quantum phase *** on the ball condition,we obtain some constraint relations about the optimal *** construct the corresponding optimal elements and then derive the Connes distance between two arbitrary Fock states of 2D quantum harmonic *** prove that these two-dimensional distances satisfy the Pythagoras *** results are significant for the study of geometric structures of noncommutative spaces,and it can also help us to study the physical properties of quantum systems in some kinds of noncommutative spaces.

关键词： Connes distance noncommutative geometry harmonic oscillator

COMPUTATIONAL FLOW RATE FEEDBACK AND CONTROL METHOD IN HYDRAULIC ELEVATORS

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Chinese Journal of Mechanical Engineering 2005年第4期18卷 490-493页

作者： Xu bing Ma Jien lin Jianjie State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

The computational flow rate feedback and control method, which can be used in proportional valve controlled hydraulic elevators, is discussed and analyzed. In a hydraulic elevator with this method, microprocessor receives pressure information from the pressure transducers and computes the flow rate through the proportional valve based on pressure-flow conversion real time algorithm. This hydraulic elevator is of lower cost and energy consumption than the conventional closed loop control hydraulic elevator whose flow rate is measured by a flow meter. Experiments arc carried out on a test rig which could simulate the load of hydraulic elevator. According to the experiment results, the means to modify the pressure-flow conversion algorithm are pointed out.

关键词： Hydraulic elevator Computational flow rate Proportional valve

A Categorification of the Boson Oscillator

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Communications in Theoretical Physics 2012年第1期57卷 34-40页

作者： lin bing-Sheng WU Ke School of Mathematical Sciences Capital Normal UniversityBeijing 100048China

In this paper,we investigate the categorical description of the boson *** on the categories constructed by Khovanov,we introduce a categorification of the Fock states and the corresponding inner product of these *** find that there are two different categorical definitions of the inner product of the Fock *** two definitions are consistent with each other,and the decategorification results also coincide with those in conventional quantum *** also find that there are some interesting properties of the 2-morphisms which relate to the inner product of the states.

关键词： categorification Boson oscillator Fock state Heisenberg algebra

Energy Spectra of the Harmonic Oscillator in a Generalized Noncommutative Phase Space of Arbitrary Dimension

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Chinese Physics Letters 2011年第7期28卷 23-26页

作者： lin bing-Sheng HENG Tai-Hua School of Mathematical Sciences Capital Normal UniversityBeijing 100048 School of Physics and Material Science Anhui UniversityHefei 230039

We use the invariant eigen-operator method to study the higher-dimensional harmonic oscillator in a type of generalized noncommutative phase space,and obtain the explicit expression of the energy spectra of the noncommutative harmonic oscillator in arbitrary *** is found that the energy spectra of the higher-dimensional noncommutative harmonic oscillator are equal to the sum of the energy spectra of some 1D harmonic oscillators and some 2D noncommutative harmonic *** believe that the properties of the harmonic oscillator may reflect some essence of the noncommutative phase space.

关键词： dimension space harmonic

Theoretical Study on the Ordered Structure in Lanthanum-Modified Lead Zirconate Titanate

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Chinese Physics Letters 1996年第9期13卷 696-699页

作者： GUI Hong ZHANG Xiao-wen GU bing-lin Department of Materials Science and Engineering Department of Physics Tsinghua UniversityBeijing 100084

The 1/2{111}-type ordered structure observed in lanthanum-modified lead zirconate titanate has been proved to be stable in the next-nearest-neighbor approximation by the eightpoint cluster variation *** order parameter as a function of the composition of La3+and lead vacancies and the order-disorder phase diagram have been obtained.

关键词： method lanthanum Modified

Recent Advances in Metal-Organic Cages-Based Composite Membranes

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Chinese Journal of Structural Chemistry 2022年第11期41卷 100-109页

作者： Guoliang Liu Xiao-Qin Liu lin-bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Material(SICAM)College of Chemical EngineeringNanjing Tech UniversityNanjing211816China State Key Laboratory of Coordination Chemistry Nanjing UniversityNanjing 210023China

Conventional polymeric membranes face several limitations,such as the trade-off between permeability and selectivity,and physical aging or membrane *** this case,fabrication of composite membranes,usually including mixed matrix membranes(MMMs)or thin film nanocomposite(TFN)membranes by introduction of porous materials as fillers has gained much *** achieve excellent membrane performance,it is of great importance to select proper porous materials to avoid agglomeration or precipitation during the composite membrane fabrication ***-organic cages(MOCs)have been explored as additives for the fabrication of defectfree composite membranes owing to their diversified topologies,well-defined pore structures,nanoscale size,and excellent *** review mainly focuses on the recent advances in applications of MOCs for membrane separation,including synthetic artificial channels,reverse osmosis,nanofiltration,pervaporation and gas ***,two types of MOCs that have been extensively investigated for composite membrane fabrication are also ***,challenges and possible directions are also discussed in details,hoping to provide insightful guidance on the development of more MOC-based membranes with impressive separation performance.

关键词： membrane separation metal-organic cage mixed matrix membranes thin film nanocomposite membranes

Catalytically generated noncovalent ammonium dienolate:a versatile platform for the development of organocatalytic asymmetric cascade reactions

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Science China Chemistry 2024年第8期67卷 2524-2546页

作者： Jun-bing lin Dong-Sheng Ji Peng-Fei Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China Shaanxi Key Laboratory of Chemical Reaction Engineering College of Chemistry and Chemical EngineeringYan’an UniversityYan’an 716000China

Organocatalytic cascade reactions represent a powerful strategy for the rapid construction of complex chiral molecules with multiple stereocenters from simple substrates under mild conditions. The intriguing structural feature and diverse reactivity of catalytically generated dienolate species render them competent and versatile intermediates for the development of practical and valuable cascade reactions. Over the past years, a plethora of innovative and pioneering noncovalent ammonium dienolatemediated cascade reactions have been designed and implemented under the catalysis of chiral organocatalysts, making dienolate activation a general, robust, and complementary method for the functionalization of unsaturated carbonyl compounds and related substances. This review illustrates the recent advances in organocatalytic noncovalent ammonium dienolate-mediated cascade reactions(mainly from 2010 to 2023), including the cascade transformations of ammonium dienolates directly generated from unsaturated ketone/aldehyde, ester/lactone/azlactone, amide/lactam/pyrazolone/oxindole, and alkylidene nitrile compounds. The contents are arranged based on the reaction types of the ammonium dienolates, with an emphasis on cascade 2,5-, 3,5-, and 4,5-difunctionalizations of these intermediates. Furthermore, other cascade reactions involving the 1,3-, 2,3-, and even more complex 3,4,5-reactivities of ammonium dienolates were also discussed. The reaction pathway, reaction stereoinduction, and synthetic applications of the ammonium dienolate-mediated cascade reactions were highlighted throughout the article. As a stimulating and ever-growing research area, the organocatalytic noncovalent ammonium dienolate-mediated cascade reactions are expected to continue demonstrating their magic power for constructing chiral targets in the future and further expanding the boundaries of asymmetric catalysis.

关键词： organocatalysis asymmetric catalysis ammonium dienolate cascade reaction difunctionalization

Oscillatory Phase Behaviour as a Function of Film Thickness due to Confinement in fcc (100) A_(3)B Alloy Thin Films

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Chinese Physics Letters 2001年第11期18卷 1504-1506页

作者： NI Jun LIU Hua GU bing-lin Department of Physics Tsinghua UniversityBeijing 100084

The order-disorder phase transitions in fcc thin films are investigated by using the mean field method. The result shows that there is a significant difference in the phase transitions and surface segregation between the films of even-number and odd-number layers. There are various types of phase transitions involving several ordered phases with spatial variation for the film of even-number layers, while there is only one phase transition for the film of odd-number layers.

关键词： transitions phase film