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Trudinger–Moser Inequalities on a Closed Riemann Surface with a Symmetric Conical Metric

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2263-2284页

作者： Yu FANG yun yan yanG College of Teacher Education Quzhou UniversityQuzhou 324003P.R.China Department of Mathematics Renmin University of ChinaBeijing 100872P.R.China

This is a continuation of our previous work(*** ***.,20,1295–1324,2020).Let(Σ,g)be a closed Riemann surface,where the metric g has conical singularities at finite *** G is a group whose elements are isometries acting on(Σ,g).Trudinger–Moser inequalities involving G are established via the method of blow-up analysis,and the corresponding extremals are also *** extends previous results of Chen(***.,1990),Iula–Manicini(Nonlinear Anal.,2017),and the authors(2020).

关键词： Trudinger-Moser inequality blow-up analysis conical singularity

Adsorption and dissociation of H_2O on Cu_2O(100): A computational study

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Journal of Natural Gas Chemistry 2011年第2期20卷 155-161页

作者： yun Li Lifen yan Guichang Wang Department of Chemistry and the Center of Theoretical and Computational Chemistry Nankai University 7ianjin 300071 China

The adsorption and dissociation of water on Cu2O（100） have been investigated by the density functional theory-generalized gradient approximation （DFT-GGA） method. The corresponding reaction energies, the structures of the transition states and the activation energies were determined. Calculations with and without dipole correction were both studied to get an understanding of the effect of the dipole moment on the adsorption and reaction of water on dipole surface Cu2O（100）. When dipole correction was added, the adsorption energies of H2O on different sites generally decreased. The calculated activation barriers for HxO （x = 1, 2） dehydrogenation are 0.42 eV （1.01 eV without the dipole correction） and 1.86 eV, respectively, including the zero point energy correction. The first dehydrogenation outcome is energetically the most stable product.

关键词： density functional calculations water dissociation metal oxide surfaces dipole corrections slab mode

Stochastic description of quantum Brownian dynamics

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Frontiers of physics 2016年第4期11卷 75-99页

作者： yun-An yan Jiushu Shao Guizhou Provincial Key Laboratory of Computational Nano-Material Science Guizhou Education University Guizhou 550018 China Center of Advanced Quantum Studies and College of Chemistry Beijing Normal University Beijing 100875 China

Classical Brownian motion has well been investigated since the pioneering work of Einstein, which inspired mathematicians to lay the theoretical foundation of stochastic processes. A stochastic formulation for quantum dynamics of dissipative systems described by the system-plus-t）ath model has been developed and found many applications in chemical dynamics, spectroscopy, quantmn transport, and other fields. This article provides a tutorial review of the stochastic formulation for quantum dissipative dynamics. The key idea is to decouple the interaction between the system and the bath by virtue of the Hubbard-Stratonovich transformation or Ito calculus so that the system and the bath are not directly entangled during evolution, rather they are correlated due to the complex white noises introduced. The influence of the bath on the system is thereby defined by an induced stochastic field, which leads to the stochastic Liouville equation for the system. The exact reduced density matrix can be calculated as the stochastic average in the presence of bath-induced fields. In general, the plain implementation of the stochastic formulation is only useful for short-time dynamics, but not efficient for long-time dynamics as the statistical errors go very fast. For linear and other specific systems, the stochastic Liouville equation is a good starting point to derive the master equation. For general systems with decomposable bath-induced processes, the hierarchical approach in the form of a set of deterministic equations of motion is derived based on the stochastic formulation and provides an effective means for simulating the dissipative dynamics. A combination of the stochastic simulation and the hierarchical approach is suggested to solve the zero-temperature dynamics of the spin-boson model. This scheme correctly describes the coherent-incoherent transition （Toulouse limit） at moderate dissipation and predicts a rate dynamics in the overdamped regime. Challenging problems su

关键词： stochastic description quantum dissipation spin-boson model hierarchical approach

Synthesis of Calix[4]resorcinarene Core Dendrimers with Peripheral Salicylideneimine Functional Groups

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Chemical Research in Chinese Universities 2006年第4期22卷 537-542页

作者： HAN Jun GE yun yan Chao-guo College of Chemistry ＆ Chemical Engineering Yangzhou University Yangzhou 225002 P. R. China

First to third-generation calix[4] resorcinarene core dendrimers, compounds 4a, 4b, 7a, 7b, 10a and 10b, were prepared via the divergent method in seven steps with the corresponding tetraphenyl- and tetra （hydroxyphenyl） calix[4] resorcinarenes （compounds 1a, 1b） as the starting material. The repeat units of the polyamidoamines of these dendrimers were obtained by the ammonolysis of ethyl calixarylacetates 2a and 2b with 1,3-diaminopropane, that is, amide derivatives with terminal amino groups, which in turn reacted with ethyl acrylate to give a higher generation of ester derivatives. The structures of these dendrimers were characterized by IR, ^1H and ^13C NMR spoctrometries. The crystal structure of compound 2b with 12 ethoxycarbonylmethoxy groups was determined by X-ray analysis.

关键词： Calixresorcinarene Dendrimer Schiffbase Amide Calixarene

Curve Shortening Flow in Arbitrary Dimensional Euclidian Space

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Acta Mathematica Sinica,English Series 2005年第4期21卷 715-722页

作者： yun yan yanG Xiao Xiang JIAO School of Mathematical Sciences Peking University Beijing 100871 P. R. China Graduate School Chinese Academy of Sciences P. R. China

In this paper, curve shortening flow in Euclidian space R^n（n≥3） is studied, and S. Altschuler＇s results about flow for space curves are generalized. We prove that the curve shortening flow converges to a straight line in infinite time if the initial curve is a ramp. We also prove the planar phenomenon when the curve shortening flow blows up.

关键词： Curve shortening flow Singularity formation Blow up

CCNO mutation as a cause of primary ciliary dyskinesia:A case report

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World Journal of Clinical Cases 2022年第25期10卷 9148-9155页

作者： yun-yan Zhang yan Lou Han yan Hao Tang Department of Respiratory and Critical Care Medicine Changzheng HospitalNaval Military Medical UniversityShanghai 200003China Department of Orthopedic Oncology Spine Tumor CenterChangzheng HospitalNaval Military Medical UniversityShanghai 200003China Department of Nephrology 905th Hospital of PLA NavyNaval Military Medical UniversityShanghai 200050China

BACKGROUND Primary ciliary dyskinesia(PCD)is an uncommon and genetically diverse *** to reports,most patients had more than 50 visits before being diagnosed with PCD,and the age at diagnosis was mostly in preschool,with an average age of about(10.9±14.4)years *** is a pathogenic gene that regulates the cell cycle,and its mutation is linked to the uncommon human genetic disorder *** the prevalence of the CCNO mutation is regarded to be exceptionally low,new reports of this mutation have increased in comparison to prior *** patients with CCNO are rare,and the incidence rate is no more than 2%in whole PCD *** SUMMARY Here,we report a case of a young Chinese woman diagnosed with PCD,who was found to carry the CCNO gene by whole exon gene *** this case,a young non-smoking Chinese female exhibiting recurrent cough and sputum at *** computed tomography(CT)showed bronchiectasis with infection,and sinus CT showed chronic ***,the patient had no visceral transposition and no history of *** electron microscope,it was found that cilia were short and reduced in number,and no power arm of cilia was *** exon sequencing analysis of the genome of the patient showed that the patient carried CCNO pathogenic gene,exon c.303C>A nonsense mutation and c.248_252dup frameshift *** clinical symptoms and CT images were improved after two months of treatment with aerosol inhalation and oral *** The results showed that CCNO is an important cause of *** mutant genes that may contribute to genetically diverse disorders like PCD have been discovered as sequencing technology has ***,the increase of genetic information makes it easier to diagnose uncommon diseases in clinical practice.

关键词： Primary ciliary immobility disorder CCNO gene Whole exon gene sequencing Clinical profiles Review of literature Case report

Propofol Brings on the Light for Depression Therapy

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Neuroscience Bulletin 2023年第12期39卷 1891-1894页

作者： yun yan Hongli Ma Jing Zhao Department of Anesthesiology China-Japan Friendship HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100029China

Major depressive disorder(MDD)is a major cause of global disability,with a global prevalence of 4.4%[1].Anhedonia is a core feature of MDD,and is associated with the longer treatment-resistant course:a third to half of patients with MDD had no response to multiple antidepressants[2].It is crucial to search the more effective target therapeutics for anhedonia to develop new *** is currently the most popular intravenous agent used for general clinical anesthesia and exerts its effect by activating-aminobutyric acid type A(GABAA)receptors.

关键词： anesthesia drugs Therapy

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基于液晶回音壁模式传感的光谱标定方法研究

光谱学与光谱分析 2025年第1期45卷 30-37页

作者：麻镇宇李晓强刘永军严云翔哈尔滨工程大学纤维集成光学教育部重点实验室黑龙江哈尔滨150001 哈尔滨工程大学海洋光子材料与器件物理工业和信息化部重点实验室黑龙江哈尔滨150001 哈尔滨工程大学青岛创新发展中心山东青岛266000

液晶回音壁模式(WGM)传感技术结合了液晶材料的高敏感性和光学WGM的高精度特性,在物质检测、环境监测和生物医疗等领域具有广阔的应用前景。为提升传感测量的精度和灵敏度,除了改善传感器的结构特性以外,如提高品质因子、实现窄线宽、... 详细信息

液晶回音壁模式(WGM)传感技术结合了液晶材料的高敏感性和光学WGM的高精度特性,在物质检测、环境监测和生物医疗等领域具有广阔的应用前景。为提升传感测量的精度和灵敏度,除了改善传感器的结构特性以外,如提高品质因子、实现窄线宽、提升波长移动范围等,准确标定WGM光谱谱线是一个重要内容。然而,实际应用中,WGM光谱的非规则分布给谱线标定带来了挑战。本文针对此问题提出了一种基于Savitzky-Golay(SG)滤波和高斯平滑的WGM非规则光谱标定方法,并提出了光谱标定的对称性、高线性和合理性三原则。将WGM光谱标定分为规则和非规则两类。对于规则光谱,具有良好的洛伦兹线型和高斯包络轮廓,可以选择最高强度谱线或中心波长,或者具有相同自由光谱范围(FSR)的相邻模式谱线作为谐振波长。而对于非规则光谱,可以分为三类:(1)光谱缺峰和强度突变,主要由于谐振条件的损耗变化所致;(2)光谱非规则劈裂,液晶微腔中可能存在微小的缺陷或杂质,导致光谱的非对称劈裂;(3)混合型变化光谱,受到复杂测量环境的影响,可能出现多种不规则变化。通过SG滤波和高斯平滑处理,有效地恢复光谱的对称性,提升拟合线性度,实现光谱标定。为验证该方法的有效性,根据不同类型光谱标定情况,分别设计了利用液晶WGM对不同生物分子的传感实验,包括胰蛋白酶(浓度0.75~2.00μg·mL^(-1))、pH(4.55~6.86)、DNA(浓度90~490μg·mL^(-1))等。实验结果表明,采用本文方法和三原则进行液晶WGM光谱标定和谐振峰选取,传感灵敏度的线性度均在0.99以上,具有较好的可靠性和稳定性。该研究创新之处在于提出了针对液晶WGM光谱非规则分布的有效标定方法和三原则,为提高液晶WGM传感测量的准确性和有效性提供了有效解决方案和重要的理论和方法支持,具有重要的应用和理论意义。

关键词：液晶回音壁模式光谱标定 Savitzky-Golay滤波

Global Gradient Estimate on Graph and Its Applications

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Acta Mathematica Sinica,English Series 2016年第11期32卷 1350-1356页

作者： Yong LIN Shuang LIU yun yan yanG Department of Mathematics Renmin University of China

Continuing our previous work （arXiv：1509.07981vl）, we derive another global gradient estimate for positive functions, particularly for positive solutions to the heat equation on finite or locally finite graphs. In general, the gradient estimate in the present paper is independent of our previous one. As applications, it can be used to get an upper bound and a lower bound of the heat kernel on locally finite graphs. These global gradient estimates can be compared with the Li-Yau inequality on graphs contributed by Bauer et al. [J. Differential Geom., 99, 359-409 （2015）]. In many topics, such as eigenvalue estimate and heat kernel estimate （not including the Liouville type theorems）, replacing the Li-Yau inequality by the global gradient estimate, we can get similar results.

关键词： Gradient estimate global gradient estimate Harnack inequality locally finite graph