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Chinese Physics C 2018年第7期42卷 47-52页

作者： Qing-hua he Department of Nuclear Science and Engineering Nanjing University of Aeronautics and Astronautics （NUAA） Nanjing 210016 China

We present a new event mixing technique for measuring two-pion Bose-Einstein correlations （BEC） in reactions with only two identical bosons among three final state particles. This new mixing method contains a missing mass consistency （MMC） cut and an energy sum order （ESO） cut. Unlike the previous proposed pion energy cut, which abandons nearly half the original events, the ESO cut does not eliminate any original events and hence improves the statistics of both original events and mixed events. Numerical tests using the γp→π0π0p events around 1 GeV are carried out to verify the validity of the ESO cut. This cut is able to reproduce the relative momentum distribution of the original events in the absence of BEC effects. In addition, its ability to observe BEC effects is tested by an event sample in the presence of BEC effects. Simulation results show the BEC effects can be observed clearly as an enhancement in the correlation function, and the BEC parameters extracted by this event mixing cut are consistent with the input BEC parameters.

关键词： Bose-Einstein correlations photoproduction event mixing

Unitary Equivalence,Similarity and Calculation of K_0-Group

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Acta Mathematica Sinica,English Series 2005年第6期21卷 1259-1268页

作者： hua he Chun Lan JIANG Department of Applied Mathematics Hebei University of Technology Tianjin 300130 P. R. China Academy of Mathematics and Systems Science Chinese Academy of ScienceBeijing 100080 P. R. China

In this paper, we are concerned with the classification of operators on complex separable Hilbert spaces, in the unitary equivalence sense and the similarity sense, respectively. We show that two strongly irreducible operators A and B are unitary equivalent if and only if W＊（A＋B）′≈M2（C）, and two operators A and B in B1（Ω） are similar if and only if A′（AGB）/J≈M2（C）. Moreover, we obtain V（H^∞（Ω,μ）≈N and Ko（H^∞（Ω,μ）≈Z by the technique of complex geometry, where Ω is a bounded connected open set in C, and μ is a completely non-reducing measure on Ω.

关键词： Strongly irreducible operators Cowen-Douglas operator Holomorphic complex bundle,Grassmann manifold K0-group

Fractionated and Confined Crystallization of Polybutene-1 in Immiscible Polypropylene/Polybutene-1 Blends

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Chinese Journal of Polymer Science 2018年第7期36卷 859-865页

作者： Yao Xu Chen-Guang Liu hua-Rong Nie Ai-hua he Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization Key Laboratory of Rubber-Plastics (Ministry of Education) School of Polymer Science and Engineering Qingdao University of Science and Technology

In this work, the crystallization of immiscible polypropylene （PP）/polybutene-1 （PB） blends, in particular the effect of crystal morphology of PP （HTC, high Tm component） on the subsequent crystallization behavior of PB （LTC, low Tm component） was studied. herein, we firstly indicated that PP/PB blends were not completely compatible but characterized as the LCST-like phase diagram above the melting temperature of PP. Crystallization of PP at different crystallization temperatures brought about different PP crystal morphologies and PB was segregated and confined at different locations. Much larger-sized domain of PB component appeared in PP spherulites resulting from the effects of non-negligible phase separation and the slower PP crystallization rate as PP crystallized at high temperature. As temperature continued to fall below Tm of PB, the fractionated and confined crystallization of PB occurred in the framework of PP spherulites, reflected by the decreased crystallization temperature （To） of PB and the formation of form I＇ beside form II. Notably, if PP previously crystallized at high Tc, fractionated crystallization of PB became predominant and confined crystallization of PB became weak due to the much wider droplet-size distribution of PB domains.

关键词： Polypropylene Polybutene Confined crystallization Morphology

Asymptotic Behavior of Impulsive Stochastic Functional Differential Equations

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Acta Mathematica Sinica,English Series 2014年第6期30卷 1061-1072页

作者： Li Guang XU Dan hua he Department of Applied Mathematics Zhejiang University of Technology Department of Mathematics Zhejiang International Studies University

In this paper, a nonlinear and nonautonomous impulsive stochastic functional differential equation is considered. By establishing a nonautonomous -operator impulsive delay inequality and using the properties of ρ-cone and stochastic analysis technique, we obtain the p-attracting set and p-invariant set of the impulsive stochastic functional differential equation. An example is also discussed to illustrate the efficiency of the obtained results.

关键词： p-attracting set p-invariant set -operator inequality stochastic impulsive

The Problem of Split Convex Feasibility and Its Alternating Approximation Algorithms

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Acta Mathematica Sinica,English Series 2015年第12期31卷 1857-1871页

作者： Zhen hua he Ji Tao SUN Department of Mathematics Tongji University Department of Mathematics Honghe University

This paper studies the problem of split convex feasibility and a strong convergent alternating algorithm is *** to this algorithm,some strong convergent theorems are obtained and an affirmative answer to the question ... 详细信息

关键词： Alternating algorithm problem of split convex feasibility strong convergent theorem

Toeplitz Operators with BMO Symbols of Several Complex Variables

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Acta Mathematica Sinica,English Series 2012年第3期28卷 599-608页

作者： Zhong hua he Guang Fu CAO School of Mathematics and Information Sciences Guangzhou University

In this note we prove that the boundedness and compactness of the Toeplitz operator on the Bergman space L2a （Bn） for several complex variables with a BMO1 symbol is completely determined by the boundary behavior of... 详细信息

关键词： Toeplitz operator Bergman space Berezin transform

PDCA nursing in improving quality management efficacy in endoscopic submucosal dissection

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World Journal of Clinical Cases 2022年第27期10卷 9611-9618页

作者： Yan-hua he Fang Wang Digestive Endoscopy Center The First Affiliated Hospital of Soochow UniversitySuzhou 215006Jiangsu ProvinceChina

BACKGROUND Endoscopic submucosal dissection(ESD) is a common surgical strategy for the treatment of early gastrointestinal tumors and precancerous *** nursing can effectively prevent potential risks in the nursing process,protect patient privacy,and improve patient satisfaction,nursing integrity,and service *** To explore the effects of PDCA nursing model on the quality management of gastrointestinal ESD,the 36-item Shot-Form health Survey(SF-36) score,and negative *** A total of 178 patients who underwent ESD between January 2020 and January 2021 were divided into two *** usual care mode was the control group,with 80 cases from January to July 2020;from July 2020 to January 2021,98 patients were enrolled in the PDCA care mode as the research *** length of hospital stay and the costs of the two groups were statistically *** visual analog scale(VAS),SF-36 score,Zung self-rating scale for anxiety and depression,and postoperative complications were also *** The length of hospitalization and cost in the research group were lower than in the control group(P he VAS scores were lower than those before care(P he VAS score of the research group was lower than that of the control group(P he SF-36 scores for physical function,role status,social function,pain,mental health,and physical strength were higher in the research group than in the control group(P he research group were lower than those of the control group(P he postoperative complication rate in the research group(6.12%) was lower than in the control group(32.50%)(P he quality of management of ESD surgery,shorten the length of hospital stay and cost,reduce the VAS and Zung scale scores to alleviate adverse emotions,improve the SF-36 score,and reduce postoperative complications.

关键词： PDCA care Endoscopic submucosal dissection 36-item Shot-Form health Survey Zung scale score Postoperative complications

Active feedback control of sound radiation in elastic wave metamaterials immersed in water with fluid-solid coupling

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Acta Mechanica Sinica 2021年第5期37卷 803-825,I0002页

作者： Zhi-hua he Yi-Ze Wang Yue-Sheng Wang Institute of Engineering Mechanics Beijing Jiaotong UniversityBeijing 100044China Department of Mechanics Tianjin UniversityTianjin 300350China

Due to their potential properties unlike traditional materials and structures,elastic wave metamaterials have received significant interests in recent *** the coupling between the acoustic and vibration,their mechanical characteristics can be tuned by the active feedback control system at low frequency ranges in which the traditional passive control is *** work illustrates that the superior performances of the effective mass density and sound pressure level(SPL)of an elastic wave metamaterial can be significantly changed by the active control,in which the periodic array of local resonators and orthogonal stiffeners are ***,based on the locally resonant mechanism,the negative density occurs over a frequency *** to the effects of lattice constant,structural damping and other parameters,the SPL with the function of fluid-solid coupling are illustrated and discussed.

关键词： Elastic wave metamaterial Local resonance Sound radiation Fluid-solid coupling Active feedback control

Electrolyte effect on electrochemical behaviors of manganese fluoride material for aqueous asymmetric and symmetric supercapacitors

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Rare Metals 2024年第3期43卷 1048-1061页

作者： Zheng-hua he Jian-Fei Gao Ling-Bin Kong State Key Laboratory of Advanced Processing and Recycling of Non-Ferrous Metals Lanzhou University of TechnologyLanzhou730050China School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou730050China

Exploring wide voltage window materials is not only an available measure to enhance the energy density of hybrid supercapacitor(HSCs),but also avoids the dynamic mismatch caused by different energy storage mechanisms of two electrodes in assembled symmetrical ***,there are few reports about the wide potential window materials except Bi_(2)O_(3)and VO_(2).Therefore,the MnF_(2)synthesized by solvothermal reaction was served as the electrode for *** MnF_(2)exhibited electrochemical activity in alkaline solution in three-electrode system,especially with a wide potential window from-0.8 to+0.5 V in 2 mol·L^(-1)***,the assembled MnF_(2)//MnF_(2)symmetrical HSC had a potential window of 1.5 V,and it exhibited outstanding long-cycle ***,when MnF_(2)was taken as the negative and positive respectively,the potential windows of asymmetric devices CoMoO_(4)//MnF_(2)and MnF_(2)//Activated Carbon(AC)could reach 1.3 and 1.45 V,respectively,showing excellent cycle *** work shows that MnF_(2)material has great research value in HSC,and provides a new research direction for developing high-performance devices.

关键词： Manganese fluoride Potential window Hybrid supercapacitors Electrochemical performance

Sound Transmission Comparisons of Active Elastic Wave Metamaterial Immersed in External Mean Flow

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Acta Mechanica Solida Sinica 2021年第3期34卷 307-325页

作者： Zhi-hua he Yi-Ze Wang Yue-Sheng Wang Institute of Engineering Mechanics Beijing Jiaotong UniversityBeijing 100044China Department of Mechanics Tianjin UniversityTianjin 300350China

Using the active feedback control system on the elastic wave metamaterial,this research concentrates on the sound transmission with the dynamic effective *** metamaterial is subjected to an incident pressure and immersed in the external mean *** elastic wave metamaterial consists of double plates and the upper and lower four-link mechanisms are attached *** vertical resonator is attached by the active feedback control system and connected with two four-link *** on the dynamic equivalent method,the metamaterial is equivalent as a single-layer plate by the dynamic effective *** the coupling between the fluid and structure,the expression of the sound transmission loss(STL)is *** research shows the influence of effective mass density on sound transmission properties,and the STL in both modes can be tuned by the acceleration and displacement feedback *** addition,the dynamic response and the STL are also changed obviously by different values of structural damping,incident angle(i.e.,the elevation and azimuth angles)and Mach number of the external fluid with the mean flow *** results for sound transmission by two methods are compared,i.e.,the virtual work principle for double plates and the dynamic equivalent method corresponding to a single *** paper is expected to be helpful for understanding the sound transmission properties of both pure single-and double-plate models.

关键词： Elastic wave metamaterials Active feedback control Dynamic equivalent method Sound transmission External mean flow