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饱和光谱中带弛豫项的光学Bloch方程的微扰解法

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物理学报 1986年第7期 855-863页

作者：王庆吉谢川北京大学无线电电子学系

本文利用微扰论方法,直接求解带弛豫项的光学Bloch方程,给出了计算各级微扰的递推公式,具体地给出了一级和二级微扰近似的解析表达式,并对所得结果做了物理解释。

关键词：弛豫项微扰近似 Bloch 能级跃迁光子效应密度矩阵方法光学喇曼粒子速度粒子性质方程微扰法一级近似色散微扰解

A Decoupling-Type Strategy for the Allen-Cahn Equation on Curved Surfaces

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Journal of Mathematical Research with Applications 2025年第1期 73-83页

作者： Xiaoman xie qing PAN School of Computer and Communication Engineering Changsha University of Science & Technology

In this paper, we construct an efficient decoupling-type strategy for solving the Allen-Cahn equation on curved surfaces. It is based on an FEM-EIEQ(Finite Element Method and explicit-Invariant Energy Quadratization) fully discrete scheme with unconditional energy stability. Spatially the FEM is adopted, using a triangular mesh discretization strategy that can be adapted to complex regions. Temporally, the EIEQ approach is considered, which not only linearizes the nonlinear potential but also gives a new variable that we combine with the nonlocal splitting method to achieve the fully decoupled computation. The strategy can successfully transform the Allen-Cahn system into some completely independent algebraic equations and linear elliptic equations with constant coefficients, we only need to solve these simple equations at each time step. Moreover, we conducted some numerical experiments to demonstrate the effectiveness of the strategy.

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A versatile synthetic strategy towards rare earth based metal-organic frameworks

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Science China Chemistry 2025年

作者： Quan Shi Yun-Hao Xu Ming-Hui Chen Peng Zhao Wen-Bo Deng ji Xiong Kai Guo Ya-qing Feng Bao Zhang School of Chemical Engineering and Technology Tianjin University Tianjin Collaborative Innovation Center of Chemical Science and Engineering Guangdong Laboratory Chemistry & Fine Chemical Industry jieyang Center

Rare earth metal-organic frameworks (RE-MOFs) have drawn wide attention owing to diverse network structures and various application ***,due to the unpredictable formation of the nodes,it is still challenging to design novel RE-MOFs.A novel versatile strategy was developed employing a RE-acetate complex (RE2(CH3COO)6·4H2O) as a precursor to construct RE-MOFs.2D RE-MOFs (RE-DBP) and 3D RE-MOFs (RE-TCPP) could be obtained by using dicarboxylic porphyrin ligands H2DBP and tetracarboxylic porphyrin ligands H2TCPP,*** RE-MOFs were further synthesized to verify the universality of the *** crystalline RE-MOFs could also be prepared at room temperature via the developed strategy,which could significantly promote large-scale preparation and practical application of *** proof of the concept,the performance of porphyrin-based RE-MOFs was investigated in the photocatalytic cycloaddition of CO2with *** the RE-DBP(Co) MOFs,Tb-DBP(Co) exhibited the best photocatalytic performance,which was also greater than that of the corresponding 3D MOF Tb-TCPP(Co) due to the optimal 2D structure and thus the accelerated photogenerated charge separation and transfer *** work not only provides a novel versatile strategy to design and develop RE-MOFs,but also proposes a promising approach for the potential bulk production of RE-MOFs at room temperature.

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Tuning the porosity of {Co12IICo8III（μ3-OH）24（X）}11+ supramolecular frameworks by reaction time for D2/H2 separation

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Science China Chemistry 2025年

作者： Zhuozhou xie Zhu Zhuo Zi-Ang Nan qing Li Xiufang Li Zi-Xiu Lu Linzhe Lü jin Liu Luyao Liu Wenjing Wang Wei Wang Daqiang Yuan You-Gui Huang State Key Laboratory of Structure Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of Sciences Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth Materials Haixi InstitutesChinese Academy of Sciences State Key Laboratory of Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry and Chemical EngineeringXiamen University

Systematicly tuning the porosities of porous materials is crucial for targeted gas mixture separation,yet it remains a longstanding *** a common strategy,altering the phenylene ring count in the organic building units has been exploited to adjust pore apertures in metal organic frameworks （MOFs） and covalent organic frameworks （COFs）,resulting in only a stepwise pore size variation of approximately 2.8?.Unlike MOFs and COFs,the porosities for supramolecular assembly frameworks are highly dependent on the packings of the molecular building units in the *** above strategy cannot be applied to supramolecular assembly frameworks and other strategies are required to adjust pore apertures in supramolecular frameworks,especially to achieve porous materials with the optimal pore size for D2/H2separation （～3?）.Here,we successfully modulate the porosity of supramolecular frameworks of[CoII1+12CoIII8L12（μ3-OH）24（X）]1clusters （L=mono-deprotonated 1-iminoisoindole-3-amine,X=ClO?4or Cl?） by controlling the duration of self-assembly *** simply adjusting the reaction time,we obtain three[CoII12CoIII8L12（μ3-OH）24（X）]11+supramolecular frameworks:[CoII12CoIII8（μ3-OH）24（ClO4）L12)]·（Cl）4·（HCO2）7（1）,[CoII12CoIII8L12（μ3-OH）24（Cl）]·（ClOI4）4·（Cl）6·（HCO2）·（H2O）10（2）,and[CoI12CoIII8L12（μ3-OH）24（Cl）]·（Cl）11·（H2O）12（3）.The different stacking patterns of the[CoII12CoIII8L12（μ3-OH）24（X）]11+clusters in these frameworks lead to significantly varied stabilities and *** 1 exhibits permanent porosity with interconnected channels and maintains stability under harsh *** contrast,compound 2 is nearly nonporous,and compound 3 becomes unstable upon *** pores of compound 1 show higher affinity to D2than H2,and the pore aperture diameter of compound 1 （～3.06?） meets the optimal porosity for D2/***,compound 1 demonstrates moderate D2/H2separation at 77 K (retention time:～7 min/g for D2/H2/Ne （10/10/80 vol%） in a flow of 5 mL

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缺钾对不同基因型香蕉根系分泌物产生及土壤钾活化的影响

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西南农业学报 2017年第3期30卷 624-628页

作者：吴宇佳张文肖彤斌符传良吉清妹谢良商海南省农业科学院农业环境与土壤研究所/农业部海南耕地保育科学观测试验站海南海口571100

为了探讨低钾胁迫对香蕉幼苗生长和根系分泌物的影响,以及不同香蕉基因型对土壤钾活化差异。通过离位溶液培养法收集香蕉根分泌物,经低温冷冻干燥器浓缩后,进行土壤钾活化试验,利用高效液相色谱(HPLC)测定分泌物中有机酸成分及含量。结... 详细信息

为了探讨低钾胁迫对香蕉幼苗生长和根系分泌物的影响,以及不同香蕉基因型对土壤钾活化差异。通过离位溶液培养法收集香蕉根分泌物,经低温冷冻干燥器浓缩后,进行土壤钾活化试验,利用高效液相色谱(HPLC)测定分泌物中有机酸成分及含量。结果表明,在低钾胁迫条件下,钾高效基因型香蕉幼苗鲜质量显著高于钾低效基因型。香蕉根系分泌物中的有机酸色谱图比较简单,钾低效基因型品种仅发现3种有机酸:草酸、酒石酸和柠檬酸,钾高效基因型品种发现了4种有机酸:是草酸、酒石酸、柠檬酸和琥珀酸。钾高效基因型根系有机酸、蛋白质和可溶性糖的分泌能力显著高于低效基因型,且含量变化与鲜质量变化趋势一致,总酚酸变化趋势正好相反。不同基因型香蕉根系分泌物对土壤钾素均有活化作用,其中广粉活化能力最强,各基因型间差异达极显著水平。低钾胁迫条件下,香蕉分泌大量有机物质,基因型之间差异较为明显,香蕉钾高效基因型根系有机酸的分泌能力和土壤钾的活化能力远高于低效基因型。

关键词：香蕉基因型根系分泌物活化有机酸低钾胁迫

Solution of Smoluchowski coagulation equation for Brownian motion with TEMOM

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Particuology 2022年第11期70卷 64-71页

作者： Mingliang xie qing He State Key Laboratory of Coal Combustion Huazhong University of Science and TechnologyWuhan 430074China Guangdong Provincial Key Laboratory of Distributed Energy Systems School of Chemical Engineering and Energy TechnologyDongguan University of TechnologyDongguan 523808China

The particle number density in the Smoluchowski coagulation equation usually cannot be solved as a whole,and it can be decomposed into the following two functions by similarity transformation:one is a function of time(the particle k-th moments),and the other is a function of dimensionless volume(self-preserving size distribution).In this paper,a simple iterative direct numerical simulation(iDNS)is proposed to obtain the similarity solution of the Smoluchowski coagulation equation for Brownian motion from the asymptotic solution of the k-th order moment,which has been solved with the Taylor-series expansion method of moment(TEMOM)in our previous *** convergence and accuracy of the numerical method are first verified by comparison with previous results about Brownian coagulation in the literature,and then the method is extended to the field of Brownian agglomeration over the entire size *** results show that the difference between the lognormal function and the self-preserving size distribution is ***,the thermodynamic constraint of the algebraic mean volume is also *** short,the asymptotic solution of the TEMOM and the self-preserving size distribution form a one-to-one mapping relationship;thus,a complete method to solve the Smoluchowski coagulation equation asymptotically is established.

关键词： Population balance equation Particle size distribution Moment method Similarity solution Brownian motion

Polaron and molecular states of a spin-orbit coupled impurity in a spinless Fermi sea

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Chinese Physics B 2021年第10期30卷 447-456页

作者： Hong-Hao Yin Tian-Yang xie An-Chun ji qing Sun Department of Physics Capital Normal UniversityBeijing 100048China

We investigate the polaron and molecular states of a fermionic atom with one-dimensional spin-orbit coupling(SOC)coupled to a three-dimensional spinless Fermi *** of the interplay among the SOC,Raman coupling and spinselected interatomic interactions,the polaron state induced by the spin-orbit coupled impurity exhibits quite unique *** find that the energy dispersion of the polaron generally has a double-minimum structure,which results in a finite center-of-mass(c.m.)momentum in the ground state,different from the zero-momentum polarons where SOC are introduced into the majority *** further tuning the parameters such as the atomic interaction strength,a discontinuous transition between the polarons with different *** may occur,signaled by the singular behavior of the quasiparticle residue and effective mass of the ***,the molecular state as well as the polaron-to-molecule transition is also strongly affected by the Raman coupling and the effective Zeeman field,which are introduced by the lasers generating SOC on the impurity *** also discuss the effects of a more general spin-dependent interaction and mass *** results would be beneficial for the study of impurity physics brought by SOC.

关键词： spin-orbit coupling polaron Fermi gas

Redistribution of Li-ions using covalent organic frameworks towards dendrite-free lithium anodes:a mechanism based on a Galton Board

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Science China Chemistry 2020年第9期63卷 1306-1314页

作者： Huanyu xie qing Hao Hongchang jin Shuai xie Zhaowei Sun Yadong Ye Chaohui Zhang Dong Wang Hengxing ji Li-Jun Wan Hefei National Laboratory for Physical Sciences at the Microscale CAS Key Laboratory of Materials for Energy ConversionDepartment of Applied ChemistryUniversity of Science and Technology of ChinaHefei 230026China CAS Key Laboratory of Molecular Nanostructure and Nanotechnology Institute of ChemistryChinese Academy of SciencesBeijing 100190China

Because of its high theoretical specific capacity and low reduction potential,Li metal is considered to be key to reaching high energy density in rechargeable *** this context,most of the research has focused on suppressing dendrite formation during Li deposition to improve the cycling reversibility and safety of the ***,covalent organic framework(COF)film coating on a commercial polypropylene separator is applied as an ion redistributor to eliminate Li *** COF crystallites consist of ordered nanochannels that hinder the movement of anions while allowing Li-ions to transport across,leading to a high Li-ion transference number of 0.77±*** transport of Li-ions across the COF film can be considered to be analogous to beads passing through a Galton Board,a model that demonstrates a statistical concept of a normal ***,an even distribution of Li-ions is obtained at the COF/Li metal *** controlled Li-ion flux yields a smooth Li metal surface after 1,000 h(500 times)of cycling,leading to a significantly improved cycling stability and reversibility,as demonstrated by Cu||Li half cells,Li||Li symmetric cells,and Li Fe PO4||Li full *** results suggest that,following the principle of a Galton Board,nanopore insulators such as COF-based materials are effective ion distributors for the different energy storage or conversion systems.

关键词： redistribution dendrite-free lithium metal anode COFs Galton Board

Sensitivity Analysis of Semi-simple Eigenvalues of Regular Quadratic Eigenvalue Problems

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Acta Mathematicae Applicatae Sinica 2015年第2期31卷 499-518页

作者： Hui-qing xie Department of Mathematics East China University of Science and Technology

This paper discusses the sensitivity analysis of semisimple eigenvalues and associated eigen-matrix triples of regular quadratic eigenvalue problems analytically dependent on several parameters. The directional derivatives of semisimple eigenvalues are obtained. The average of semisimple eigenvalues and corresponding eigen-matrix triple are proved to be analytic, and their partial derivatives are given. On these grounds, the sensitivities of the semisimple eigenvalues and corresponding eigenvector matrices are defined.

关键词： sensitivity analysis quadratic eigenvalue problems multiple eigenvalue matrix-valued functions