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Acta Mathematica Sinica,English Series 2024年第8期40卷 1850-1874页

作者： Chun Mao HUANG Rui ZHANG zhi qiang gao Department of Mathematics Harbin Institute of Technology(Weihai)Weihai 264209P.R.China School of Mathematical Sciences Beijing Normal UniversityBeijing 100875P.R.China

Let(Zn)be a supercritical branching process with immigration in an independent and identically distributed random *** necessary moment conditions,we show the exact convergence rate in the central limit theorem on log Zn and establish the corresponding local limit theorem by using the moments of the natural submartingale and the convergence rates of its *** similar approach and with the help of a change of measure,we also present the so-called integrolocal theorem and integral large deviation theorem to characterize the precise asymptotics of the upper large deviations.

关键词： Branching process with immigration random environment central limit theorem large deviation

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Exact Convergence Rate of the Local Limit Theorem for a Branching Random Walk in Zd with a Random Environment in Time

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Chinese Annals of Mathematics,Series B 2024年第5期45卷 805-822页

作者： Jian-xin LIU zhi-qiang gao School of Mathematical Sciences Beijing Normal University Laboratory of Mathematics and Complex Systems (Ministry of Education) School of Mathematical Sciences Beijing Normal University

Abstract Consider a branching random walk with a random environment in time in the d-dimensional integer *** branching mechanism is governed by a supercritical branching process,and the particles perform a lazy random walk with an independent,non-identical increment *** A?Zd,let Z_n（A） be the number of offsprings of generation n located in *** exact convergence rate of the local limit theorem for the counting measure Zn（·） is *** partially extends the previous results for a simple branching random walk derived by gao （2017,*** Appl.）.

关键词： 60F05 60G50 60J10 60J80 Branching random walk Exact convergence rate Local limit theorems Random environment

Asymptotic expansions in the central limit theorem for a branching Wiener process

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Science China Mathematics 2021年第12期64卷 2759-2774页

作者： zhi-qiang gao Quansheng Liu Laboratory of Mathematics and Complex Systems(Ministry of Education) School of Mathematical SciencesBeijing Normal UniversityBeijing 100875China LMBA Campus de TohannicUniversite de Bretagne-SudCNRS UMR 6205Vannes F-56000France

We consider a branching Wiener process in R^(d),in which particles reproduce as a super-critical Galton-Watson process and disperse according to a Wiener *** B⊂R^(d),let Z_(n)(B) be the number of particles of generation n located in *** study of the central limit theorem and related results about the counting measure Z_(n)(·)is important because such results give good descriptions of the con guration of the branching Wiener process at time *** earlier works,the exact convergence rate in the central limit theorem and the asymptotic expansion until the third order have been ***,we establish the asymptotic expansion of any order in the central limit theorem under a moment condition of the form EX(logX)^(1+λ)<∞.

关键词： branching Wiener process asymptotic expansion central limit theorem

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Pyoderma gangrenosum confused with congenital preauricular fistula infection: A case report

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World Journal of Clinical Cases 2020年第9期8卷 1679-1684页

作者： Yang Zhao Rou-Yu Fang Guo-Dong Feng Ting-Ting Cui zhi-qiang gao Department of Otolaryngology Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Department of Dermatology Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China

BACKGROUND Pyoderma gangrenosum resulting from or associated with congenital preauricular fistula is rarely *** SUMMARY We report a rare case of pyoderma gangrenosum misdiagnosed as preauricular fistula *** our knowledge,this is the first report to describe pyoderma gangrenosum originating from the site of preauricular *** lesion continued expanding even after combined treatment of systemic antibiotics and thorough *** into account the possibility of pyoderma gangrenosum,we applied soft care with normal saline and Vaseline gauze *** corticosteroids were not used until intestinal Clostridium difficile was *** local recurrence was noted at the 12-mo *** This case highlights the necessity of considering rare diseases,such as pyoderma gangrenosum,when the preauricular sinus deteriorates with general *** treatment strategy is mutually conflicting between pyoderma gangrenosum and infection of the preauricular sinus.

关键词： Preauricular fistula Pyoderma gangrenosum Glucocorticoids Case report

Nomogram for predicting non-proliferative vitreoretinopathy probability after vitrectomy in eyes with rhegmatogenous retinal detachment

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International Journal of Ophthalmology(English edition) 2023年第2期16卷 215-223页

作者： zhi-qiang gao Pei-Yu Wu Jing Zhang zhi-Sheng Ke Xu-Ting Hu Zhao-Liang Zhang Jing-Wei Zheng Zong-Duan Zhang Qin-Tuo Pan Department of Ophthalmology the Third People’s Hospital of Yuhang DistrictHangzhou 311115Zhejiang ProvinceChina Department of Fundus Surgery Eye Hospital and School of Ophthalmology and OptometryWenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina Department of Ophthalmic Clinic Eye Hospital and School of Ophthalmology and OptometryWenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina Department of Gastroenterology the First People’s Hospital of Linping DistrictHangzhou 311100Zhejiang ProvinceChina

AIM:To identify the risk factors for postoperative proliferative vitreoretinopathy(PVR)in patients with primary rhegmatogenous retinal detachment(RRD)and develop a nomogram for predicting postoperative PVR-free ***:A total of 741 patients(741 eyes)diagnosed with primary RRD who underwent first surgery in the same hospital were retrospectively reviewed and randomly assigned with 521 to the training set and 220 to the validation *** and multivariate logistic regression analyses were performed in the training cohort to determine risk factors to construct a nomogram for predicting the 3-,4-,5-,and 6-month postoperative PVR-free *** performance was estimated by the concordance index(C-index),calibration plot,and the area receiver operating characteristic(ROC)***:A nomogram was constructed based on the preoperative PVR,silicone oil tamponade time(SOTT),photocoagulation energy(PE),retinal tear size(RTS),and *** the training set,the C-index of the nomogram was 0.896,0.936,0.961,and 0.972 at 3,4,5,and 6mo,*** C-index values in the validation set were 0.860,0.936,0.951,and 0.965 at 3,4,5,and 6mo,***-curve analysis indicated that only the 4-,5-,and 6-month nomograms had significant net benefits over a large threshold probabilities ***:Preoperative PVR,SOTT,PE,RTS,and hypertension are significant risk factors for postoperative PVR formation in patients with primary *** proposed nomogram can effectively predict the 4-,5-,and 6-month PVR-free probabilities after surgery and assist in making clinical decisions during follow-up.

关键词： nomogram proliferative vitreoretinopathy rhegmatogenous retinal detachment risk factor

Effect of lanthanum on inclusions in non-oriented electrical steel slabs

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Journal of Iron and Steel Research International 2024年第7期31卷 1680-1691页

作者： qiang Ren zhi-yuan Hu Yun-xia Liu Wei-cheng Zhang Zi-qi gao Li-feng Zhang School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Research and Development Department Shougang Zhixin Qian'an Electromagnetic Material Co.Ltd.Qian'an 064400HebeiChina School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

The effect of lanthanum on the characteristics of inclusions in the slab of non-oriented electrical steels was investigated through industrial trials and thermodynamic *** number,size,and chemical composition of inclusions in the surface,one-quarter of thickness and the center of slabs with and without lanthanum addition were statistically analyzed using an automatic inclusion analysis *** the lanthanum-free slab,inclusions were predominately ***_(2)O_(3),MgO,and AlN as well as a small number of Al_(2)O_(3)-MgO-CaO and *** number densities of oxide inclusions and AlN decreased from the surface to the center of the slab,which was ascribed to the difference in cooling intensity during the continuous *** the steel with lanthanum addition,inclusions were modified into LaAlO_(3) and La_(2)O_(2)S and gradually transformed into dual-phase MgO-La_(2)S3 with an increasing distance from the slab surface due to the reaction between the lanthanum-containing inclusion and the steel *** uneven distribution of oxide inclusions along the thickness of the slab was eliminated in the lanthanum-bearing slab because the dissolved oxygen was remarkably decreased by ***-bearing inclusions were more likely to agglomerate AlN by inducing the heterogeneous nucleation of AlN on their surface,while small-size ***_(2)O_(3) inclusions hardly showed a coarsening effect on the size of AlN.

关键词： Lanthanum-Inclusion Non-oriented electrical steel Aluminum nitride Heterogenous nucleation

Perichondrium/cartilage composite graft for repairing large tympanic membrane perforations and hearing improvement

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中华医学杂志(英文版) 2010年第3期123卷 301-304页

作者： Xiao-wei Chen Hua Yang Ru-zhen gao Rong Yu zhi-qiang gao Department of Otolaryngology-Head and Neck Surgery Peking Union Medical College Hospital Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100730 China. chenxw_pumch@***

Background The main risk factors for postoperative failure in tympanoplasties are large perforations that are difficult torepair,annular perforations,and a tympanic membrane (TM) with extensive granular myringitis that require middle earexploration and *** aim of this study was to investigate a novel technique of perichondrium/cartilagecomposite graft for repairing the large TM perforation in the patient of otitis *** Retrospective chart reviews were conducted for 102 patients with large tympanic membrane perforations,who had undergone tympanoplasty from August 2005 to August *** or tympanomastoidectomy using aperichondrium/cartilage composite graft was *** tragal or conchal perichondrium/cartilage was used toreplace the tympanic membrane in *** Patients aged from 13 to 67 years were followed up in average for 24 months (10-36 months).Seventy-fourears (72.61%) were used the tragal perichondrium/cartilage as graft material and 27 ears (27.39%) were used theconchal perichondrium/*** take was successful in all *** complications such as woundinfection,hematoma,or sensorineural hearing loss were not *** patients (8.82%) had the partial ossicularreplacement prosthesis,14 patients (13.72%) using the autologous curved incus and 79 patients (77.45%) *** closure occurred in 92% of the ears.A total of 85.8% patients achieved a postoperative *** The graft underlay tympanoplasty using perichondrium/cartilage composite is effective for the majority ofpatients with large *** hearing was improved even if the mastoidectomy was required in the patients withotitis media with extensive granulation.

关键词： otitis media perichondrium/cartilage tympanoplasty tympanomastoidectomy hearing improvement

Research on thermal insulation materials properties under HTHP conditions for deep oil and gas reservoir rock ITP-Coring

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Petroleum Science 2024年第4期21卷 2625-2637页

作者： zhi-qiang He He-Ping Xie Ling Chen Jian-Ping Yang Bo Yu Zi-Jie Wei Ming-Zhong gao State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering College of Water Resource and Hydropower Sichuan University Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Institute of Deep Earth Sciences and Green Energy College of Civil and Transportation Engineering Shenzhen University School of Mechanical Engineering Sichuan University College of Polymer Science and Engineering Sichuan University

Deep oil and gas reservoirs are under high-temperature conditions, but traditional coring methods do not consider temperature-preserved measures and ignore the influence of temperature on rock porosity and permeability, resulting in distorted resource assessments. The development of in situ temperaturepreserved coring(ITP-Coring) technology for deep reservoir rock is urgent, and thermal insulation materials are key. Therefore, hollow glass microsphere/epoxy resin thermal insulation materials(HGM/EP materials) were proposed as thermal insulation materials. The materials properties under coupled hightemperature and high-pressure(HTHP) conditions were tested. The results indicated that high pressures led to HGM destruction and that the materials water absorption significantly increased; additionally,increasing temperature accelerated the process. High temperatures directly caused the thermal conductivity of the materials to increase; additionally, the thermal conduction and convection of water caused by high pressures led to an exponential increase in the thermal conductivity. High temperatures weakened the matrix, and high pressures destroyed the HGM, which resulted in a decrease in the tensile mechanical properties of the materials. The materials entered the high elastic state at 150.C, and the mechanical properties were weakened more obviously, while the pressure led to a significant effect when the water absorption was above 10%. Meanwhile, the tensile strength/strain were 13.62 MPa/1.3%and 6.09 MPa/0.86% at 100.C and 100 MPa, respectively, which meet the application requirements of the self-designed coring device. Finally, K46-f40 and K46-f50 HGM/EP materials were proven to be suitable for ITP-Coring under coupled conditions below 100.C and 100 MPa. To further improve the materials properties, the interface layer and EP matrix should be optimized. The results can provide references for the optimization and engineering application of materials and thus technical su

关键词： Deep oil and gas reservoir rock In situ temperature-preserved coring (ITP-Coring) Hollow glass microsphere/epoxy resin thermal insulation materials (HGM/EP materials) High-temperature and high-pressure (HTHP) Physical and mechanical properties

Design and fabrication of lightweight AlCrFeNiTi_(x) compositionally complex alloys with exceptional specific strength

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Rare Metals 2024年第7期43卷 3314-3328页

作者： Jun-zhi Li Wei-Zong Bao Jie Chen Bo-Hua Yu Kun Zuo Tian gao Ze-Yun Cai Guo-qiang Xie School of Materials Science and Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China

This study focuses on compositionally complex alloys(CCAs),aiming to achieve a balance between high strength and low density for new energy and aerospace *** composition of AlCrFeNiTi_(x) CCAs is strategically guided by employing density functional theory and the theoretical design of thermodynamic *** CCAs,particularly AlCrFeNiTi_(0.25) alloy,demonstrate remarkable specific yield strength(1640.8 MPa) and 22.7% maximum *** incorporation of Ti facilitates the formation of lightweight and high-strength L2_(1)phase,contributing to the overall high specific *** effects of grain boundary strengthening,solid solution strengthening,Orowan strengthening and Peierls flow stress further enhance *** exploration of micros tructural changes during fracture reveals the role of ordered phases in suppressing crack propagation and absorbing energy within disordered phases,thereby improving the toughness and fracture resistance of *** methods and discoveries establish a robust foundation for advancing the development of novel lightweight CCAs.

关键词： Lightweight Compositionally complex alloys Specific yield strength

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Micromechanics of Thermal Conductive Composites:Review,Developments and Applications

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Acta Mechanica Solida Sinica 2024年第2期37卷 215-237页

作者： Guannan Wang Yulin Huang Mengyuan gao qiang Chen Department of Civil Engineering Zhejiang UniversityHangzhou310058China Center for Balance Architecture Zhejiang UniversityHangzhou310007China School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an710049China

Micromechanics investigations of composites with fiber-shaped reinforcement are extensively applied in the engineering design and theoretical analysis of thermal composites in the aerospace engineering and high-tech *** this paper,a critical review of various classical micromechanics approaches is provided based on the classification framework and the development of micromechanics *** numerical micromechanics tools have been developed to overcome limitations through exactly/approximately solving the internal governing equations of *** connections and limitations of those models are also investigated and discussed,based on which three recently developed numerical or semi-analytical models are explained,including finite-element micromechanics,finite-volume direct averaging micromechanics,and locally exact homogenization theory,as well as machine learning *** it is almost inevitable to mention the interfacial effects on thermal behavior of fibrous composites,we review the new mathematical relations that interrupt the original continuity conditions due to the existence of interphase/interface within unit *** speaking,the interphase/interface is demonstrated to play a significant role in influencing the effective coefficients and localized thermal *** present work also briefly reviews the application of micromechanics tools in emerging engineered woven composites,natural fibrous composites,and ablative thermal protection *** is demonstrated that sophisticated micromechanics tools are always demanded for investigating the effective and localized responses of thermal fibrous composites.

关键词： Micromechanics models Thermal fibrous composites Microstructural detail-free models Semi-analytical and numerical methods Interfacial effects Woven composites Natural composites