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Chinese Journal of Chemical Engineering 1997年第3期5卷 12-19页

作者：郑大庆郭天民 High Pressure Fluid Phase Behavior & Property Research Laboratory University of Petroleum

The three-parameter Petal-Teja equation of state coupled with a characterization proceduref0r C7+-fraction based on gamma distribution function was employed to predict the phase behaviorof eight gas condensates.The lumping of the subdivided single carbon number（SCN）hydrocarbons inthe plus-fraction and the choice of empirical correlations for calculating the critical properties andacentric factor of SCN hydrocarbons were discussed.

关键词： gas condensates phase behavior equation of state prediction characterization of plus-fraction

Atomic force microscopy observation of the condensates of the spermidine-DNA complexes

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Science China Chemistry 1998年第4期41卷 418-423页

作者：林璋王琛苏明田芳马金白春礼 Institute of Chemistry Chinese Academy of Sciences Beijing China

In vitro investigation on the condensation of DNA induced by naturally occurring polyamines can provide useful insights into the packaging state of DNA in vivo , which is closely related to the mechanism of the self regulation or self switching of the gene expression. The present paper reports the high resolution AFM observations of the condensates of spermidine DNA complexes. It was found that the spermidine can directly condense the DNA into toroidal structures. The formation of this special structure is greatly influenced by the dynamic factors such as the concentrations and the reaction time. Close examination revealed that the toroids were constructed by many particles stacked and squeezed together. Our observations indicate that the dynamic process of the toroid formation may be a spiral wound process of the globular subunits.

关键词： toroidal condensates spermidine AFM spiral wound process of globular subunits.

Stationary States and Modulational Instability of Coupled Two-Component Bose–Einstein condensates in a Ring Trap

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Communications in Theoretical Physics 2015年第8期64卷 133-138页

作者：邓海明钟宏华黄嘉豪代慧姚敏黄小益 School of Electronic Information and Electrical Engineering Xiangnan University School of Physics and Engineering Sun Yat-sen University Department of Physics Jishou University

We investigate modulational instability(MI) of a coupled two-component Bose–Einstein condensates in a rotating ring trap. The excitation spectrum and the MI condition of the system are presented analytically. We find that the coupling between the two components strongly modifies the MI condition, and the MI condition is phase-dependent.Furthermore, we discuss the effect of MI on both density excitation and spin excitation. If the inter- and intra-component interaction strengths are all equal, the MI causes density excitation but not spin excitation, and if the inter- and intracomponent interaction strengths are different, the MI causes both density excitation and spin excitation. Our results provide a promising approach for controlling the stability and excitation of a rotating two-component Bose–Einstein condensates by modulating its coupling strength and interaction strength.

关键词： two-component Bose–Einstein condensates modulation

Quantum Entanglement of Many Distant Bose–Einstein condensates in an Optical Lattice by Interference

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Communications in Theoretical Physics 2014年第7期61卷 13-16页

作者：刘亚峰邹旭波郭光灿 Key Laboratory of Quantum Information University of Science and Technology of China Chinese Academy of Sciences

We propose a scheme to generate maximally entangled states of two distant Bose–Einstein condensates,which are trapped in different potential wells of a one-dimensional optical lattice. We show how such maximally entangled state can be used to test the Bell inequality and realize quantum teleportation of a Bose–Einstein condensate state. The scheme proposed here is based on the interference of Bose-Einstein condensates leaking out from different potential wells of optical lattice. It is briefly pointed out that this scheme can be extended to generate maximally entangled Greenberger–Horne–Zeilinger(GHZ) states of 2m(m > 1) distant Bose–Einstein condensates.

关键词： quantum entanglement Bose–Einstein condensates optical lattice cold atomic

Modulational Instability of Trapped Two-Component Bose-Einstein condensates

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Chinese Physics Letters 2019年第9期36卷 10-13页

作者：周建文李晓旬高瑞秦文山蒋浩浩李涛涛薛具奎 College of Physics and Electronics Engineering Northwest Normal University

The modulational instability of two-component Bose-Einstein condensates(BECs)under an external parabolic potential is discussed.Based on the trapped two-component Gross-Pitaevskill equations,a time-dependent dispersion relation is obtained analytically by means of the modified lens-type transformation and linear stability analysis.It is shown that a modulational unstable time scale exists for trapped two-component BECs.The modulational properties-which are determined by the wave number,external trapping parameter,intraand inter-species atomic interactions-are modified significantly.The analytical results are confirmed by direct numerical simulation.Our results provide a criterion for judging the occurrence of instability of the trapped two-component BECs in experiment.

关键词： Modulational Instability of Trapped Two-Component Bose-Einstein condensates Component

Phase separation in plants:New insights into cellular compartmentalization

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Journal of Integrative Plant Biology 2021年第11期63卷 1835-1855页

作者： Xiumei Xu Canhui Zheng Dandan Lu Chun‐Peng Song Lixin Zhang State Key Laboratory of Crop Stress Adaptation and Improvement School of Life SciencesHenan UniversityKaifeng 475004China

A fundamental challenge for cells is how to coordinate various biochemical reactions in space and time. To achieve spatiotemporal control, cells have developed organelles that are surrounded by lipid bilayer membranes. Further, membraneless compartmentalization, a process induced by dynamic physical association of biomolecules through phase transition offers another efficient mechanism for intracellular organization. While our understanding of phase separation was predominantly dependent on yeast and animal models, recent findings have provided compelling evidence for emerging roles of phase separation in plants. In this review, we first provide an overview of the current knowledge of phase separation, including its definition, biophysical principles, molecular features and regulatory mechanisms. Then we summarize plant-specific phase separation phenomena and describe their functions in plant biological processes in great detail. Moreover, we propose that phase separation is an evolutionarily conserved and efficient mechanism for cellular compartmentalization which allows for distinct metabolic processes and signaling pathways, and is especially beneficial for the sessile lifestyle of plants to quickly and efficiently respond to the changing environment.

关键词： cellular compartmentalization changing environment condensates liquid droplets phase separation

Phase separation in RNA biology

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Journal of Genetics and Genomics 2021年第10期48卷 872-880页

作者： Yi Lin Xiaofeng Fang School of Life Sciences Tsinghua UniversityBeijing 100084China

The formation of biomolecular condensates via liquid-liquid phase separation(LLPS)is an advantageous strategy for cells to organize subcellular compartments for diverse functions.The involvement of LLPS is more widespread and overrepresented in RNA-related biological processes.This is in part because that RNAs are intrinsically multivalent macromolecules,and the presence of RNAs affects the formation,dissolution,and biophysical properties of biomolecular condensates formed by LLPS.Emerging studies have illustrated how LLPS participates in RNA transcription,splicing,processing,quality control,translation,and function.The interconnected regulation between LLPS and RNAs ensures tight control of RNA-related cellular functions.

关键词： Phase separation RNA biology condensates Membrane-less organelle

Self-trapped spatially localized states in combined linear-nonlinear periodic potentials

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Frontiers of physics 2020年第1期15卷 17-24页

作者： Jin-Cheng Shi Jian-Hua Zeng State Key Laboratory of Transient Optics and Photonics Xi’an Institute of Optics and Precision Mechanics of CASXi’an 710119China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for Physical Electronics and Devices of the Ministry of Education&Shaanxi Key Lab of Information Photonic Technique Xi’an Jiaotong UniversityXi’an 710049China

We analyze the existence and stability of two kinds of self-trapped spatially localized gap modes,gap solitons and truncated nonlinear Bloch waves,in one-and two-dimensional optical or matter-wave media with self-focusing nonlinearity,supported by a combination of linear and nonlinear periodic lattice potentials.The former is found to be stable once placed inside a single well of the nonlinear lattice,it is unstable otherwise.Contrary to the case with constant self-focusing nonlinearity,where the latter solution is always unstable,here,we demonstrate that it nevertheless can be stabilized by the nonlinear lattice since the model under consideration combines the unique properties of both the linear and nonlinear lattices.The practical possibilities for experimental realization of the predicted solutions are also discussed.

关键词： gap solitons and gap waves Bose-Einstein condensates linear and nonlinear periodic potentials

Supramoleuclar Peptide condensates Formed through Liquid-Liquid Phase Separation

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Supramoleuclar Peptide Condensates Formed through Liquid-Liq...

Interference properties of two-component matter wave solitons

2021年全国生物相分离和相变学术研讨会

作者： Xuehai Yan Chengqian Yuan Xiaokang Ren State Key Laboratory of Biochemical Engineering 2 Center for MesoscienceInstitute of Process EngineeringChinese Academy of Sciences

Peptide and protein self-assembly is of critical importance as a tool to understand the natural life phenomenon such as liquid-liquid phase separation（LLPS） in cells.Although a number of studies have demonstrated the formation of biomolecular condensates through LLPS in cells,the fundamental molecular events underpinning the early stages of their assembly and subsequent growth have remained challenging to elucidate.Herein,we will present how simple peptides can be used as a model to investigate the LLPS events in supramoleuclar self-assembly.We discover that LLPS is a fundamental step leading to nucleation of supramolecular nanostructures,and the metastable droplets（condensates） can be controlled to direct the final assembled supramolecular structures including nanoparticles,nanofibrils and nanotubes as well as crystals so on.The peptide-rich liquid droplets promote the formation of nucleation sites,allowing the emergence of thermodynamically favorable nanostructures following Ostwald’s step rule.It is found that the LLPS may be triggered mainly by an entropy effect associated with the debonding between peptides and solvent molecules（desolvation）.These results provide insights into the fundamental role of metastable liquid phases（condensates） in supramolecular self-assembly and importantly offer useful reference for comprehending the LLSP events in the complex cells.

关键词： Peptide Metastable liquid droplets condensates Liquid-liquid phase separation Self-assembly

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Chinese Physics B 2020年第2期29卷 112-120页

作者：秦艳红伍勇赵立臣杨战营 School of Physics Northwest UniversityXi'an 710127China Shaanxi Key Laboratory for Theoretical Physics Frontiers Xi'an 710127China School of Public Management Northwest UniversityXi'an 710127China

Wave properties of solitons in a two-component Bose-Einstein condensate are investigated in detail.We demonstrate that dark solitons in one of components admit interference and tunneling behavior,in sharp contrast to the scalar dark solitons and vector dark solitons.Analytic analyses of interference properties show that spatial interference patterns are determined by the relative velocity of solitons,while temporal interference patterns depend on the velocities and widths of two solitons,differing from the interference properties of scalar bright solitons.Especially,for an attractive interactions system,we show that interference effects between the two dark solitons can induce some short-time density humps(whose densities are higher than background density).Moreover,the maximum hump value is remarkably sensitive to the variation of the solitons'parameters.For a repulsive interactions system,the temporal-spatial interference periods of dark-bright solitons have lower limits.Numerical simulation results suggest that interference patterns for the dark-bright solitons are more robust against noises than bright-dark solitons.These explicit interference properties can be used to measure the velocities and widths of solitons.It is expected that these interference behaviors can be observed experimentally and can be used to design matter wave soliton interferometer in vector systems.

关键词： solitons interference behavior tunneling dynamics two-component Bose-Einstein condensates