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高能重离子诱发核反应中灰粒子产生

核技术 1999年第7期22卷 395-398页

作者：王晓荣钱琬燕台安萨本豪蔡勖华中师范大学粒子物理研究所武汉430079 中国科学院高能物理研究所北京100039 中国原子能科学研究院北京102413

采用EMU01国际合作组的原子核乳胶为探测器，系统地研究了能量为14．6、60、200GeV／u的^(16)O核、200GeV／u的^(32)S核诱发核反应中产生的灰粒子平均多重数及角分布。以描写相对论性核-核碰撞的LUCIAE模型为基础，进行MonteCarlo模拟... 详细信息

采用EMU01国际合作组的原子核乳胶为探测器，系统地研究了能量为14．6、60、200GeV／u的^(16)O核、200GeV／u的^(32)S核诱发核反应中产生的灰粒子平均多重数及角分布。以描写相对论性核-核碰撞的LUCIAE模型为基础，进行MonteCarlo模拟的结果与实验数据一致。

关键词：高能重离子反应核反应灰粒子

相对论核-核碰撞中产生的Λ超子的退极化原因探讨

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高能物理与核物理 2000年第2期24卷 125-130页

作者：叶云秀陈志阮图南沈激吕海江董卫江萨本豪台安中国科学技术大学近代物理系中国高等科学技术中心(世界实验室) 中国科学技术大学近代物理系合肥230026 中国原子能科学研究院中国科学院高能物理研究所

对每核子 2 0 0GeV的S +Pb中心碰撞中产生的Λ粒子的横向极化度消失的现象作了细致研究 .用相对论核 -核碰撞的Monte Carlo事例产生器———LUCIAE产生了相应能量下的S+Pb中心碰撞事例 ,定量地分析了消除Λ粒子横向极化度的各种因素 ,... 详细信息

对每核子 2 0 0GeV的S +Pb中心碰撞中产生的Λ粒子的横向极化度消失的现象作了细致研究 .用相对论核 -核碰撞的Monte Carlo事例产生器———LUCIAE产生了相应能量下的S+Pb中心碰撞事例 ,定量地分析了消除Λ粒子横向极化度的各种因素 ,研究了反应中的二次散射、二次产生以及Σ ,Ξ等超子衰变产生的Λ粒子在总的实验测量到的Λ总数中的比例 ,确定了由这些Λ粒子造成的退极化度对总的Λ极化度的影响 .模拟和计算结果表明 ,以上 3个效应强烈地影响了Λ的横向极化度 ,但不可能使终态假定为强子气时Λ粒子的横向极化度完全消失 .为了解释Λ极化度近于零的实验结果 ,可能需要在相对论重核碰撞中引进Λ粒子产生的新的机制 ,包括存在形成夸克 -胶子等离子体 (QGP)

关键词： A退极化事例产生器夸克-胶子等离子体相对论核-核碰撞横向极化度二次散射 A超子

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相对论重离子碰撞中粒子产生和/比率

高能物理与核物理 2000年第8期24卷 743-747页

作者：陆中道萨本豪松田正典永田纯一中村纯宫村修中国高等科学技术中心日本广岛大学综合科学部日本广岛大学理学部

利用强子输运 -弦碎裂模型研究了 2 0 0AGeV重离子碰撞中 Λ多重产生和 Λ / p比率 .研究了它们随反应系统大小和碰撞中心度的变化 .研究表明 Λ和 p多重数都随反应系统增大和随碰撞中心度提高而增大 ,但它们的比率基本保持不变 .... 详细信息

利用强子输运 -弦碎裂模型研究了 2 0 0AGeV重离子碰撞中 Λ多重产生和 Λ / p比率 .研究了它们随反应系统大小和碰撞中心度的变化 .研究表明 Λ和 p多重数都随反应系统增大和随碰撞中心度提高而增大 ,但它们的比率基本保持不变 . Λ的湮没截面大小变化对 Λ的多重数产生有一定影响 ,但对 Λ / p比率影响不大 .结果很好地再现了 pp反应中 Λ/ p比率 .并获得这一比率在AA反应中是pp反应中的 3—

关键词：相对论重离子碰撞 ∧/P比率 ∧粒子

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部分子在核中多次散射的蒙特卡罗模拟

高能物理与核物理 1988年第2期 203-207页

作者：萨本豪杨夏周白希祥中国原子能科学研究院中国原子能科学研究院北京

本文提出了用输运理论处理部分子在核中多次硬散射的方法和相应的蒙特卡罗技巧.用偏畸抽样办法克服了Q~2依赖性的困难.作为例子,计算了p(E_p=400GeV)+W反应中π~+产生对p+p反应中π~+产生的比值.计算结果与实验符合得相当好.

关键词：部分子输运理论蒙特卡罗模拟靶核多次散射

SU(2)格点规范Monte-Carlo的非禁闭迹象

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高能物理与核物理 1988年第5期 601-607页

作者：萨本豪朱正坤张孝泽金星南中国原子能科学研究院苏州大学中国原子能科学研究院北京

本文用蒙特卡罗模拟方法讨论了SU(2)纯格点规范场(8~3×4点阵)的有限温度问题及其相应的零温问题(8~4点阵).并计算了系统的能量密度、热容和熵密度.它们的温度行为均表明在T/A_L=40-50区域有非禁闭相变发生.

关键词：有限温度空间方向点阵能量密度能量浓度 SU Monte-Carlo 格点规范理论函数关系完全相关

Effect of fore/aft-loaded rotor on compressor stability under inlet circumferential distortion

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Chinese Journal of Aeronautics 2024年第5期37卷 199-213页

作者： Dakun SUN benhao GU Fangfei NING Dengke XU Xiaofeng SUN School of Energy and Power Engineering Beihang UniversityBeijing 102206China Research Institute of Aero-engine Beihang UniversityBeijing 102206China

A modified small perturbation stability prediction model for axial compressors with circumferential inlet distortions is established and applied to investigate the effect of fore/aft-loaded rotor on compressor stability under circumferentially distorted inlet *** inlet total pressure distribution downstream of the distortion screen is measured in experiments and employed for simulations which are implemented via time-space spectral *** stall inception prediction results via the stability model indicate that the compressor with aft-loaded rotor not only performs better in terms of stability under uniform inlet,but also maintains a larger stability margin under circumferentially distorted *** experiments for compressors with fore-loaded and aft-loaded rotor are respectively carried *** results validate the reliability of numerical simulations and the predicted conclusion that the aft-loaded rotor is beneficial for compressor ***,the ability of the developed theoretical model for compressor stability prediction under circumferential distortions is *** addition,dynamic pressure signals at rotor tip measured in experiments illustrate that the circumferential distortion has little effect on the compressor stall pattern.

关键词： Axial compressor stability Inlet distortion Blade loading Small perturbation Time-space spectral method

A Methodology for Assessing Axial Compressor Stability with Inlet Temperature Ramp Distortion

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Journal of Thermal Science 2024年第3期33卷 856-871页

作者： SUN Dakun GU benhao NING Fangfei FANG Yibo DONG Xu XU Dengke SUN Xiaofeng School of Energy and Power Engineering Beihang UniversityBeijing102206China Research Institute of Aero-engine Beihang UniversityBeijing102206China

Based on a small perturbation stability model for periodic flow,the effects of inlet total temperature ramp distortion on the axial compressor are investigated and the compressor stability is quantitatively *** the beginning,a small perturbation stability model for the periodic flow in compressors is proposed,referring to the governing equations of the Harmonic Balance *** stability model is validated on a single-stage low-speed compressor TA36 with uniform inlet ***,the unsteady flow of TA36 with different inlet total temperature ramps and constant back pressure is simulated based on the Harmonic Balance *** on these simulations,the compressor stability is analyzed using the proposed small perturbation ***,the Dynamic Mode Decomposition method is employed to accurately extract pressure *** two parameters of the temperature ramp,ramp rate and Strouhal number,are discussed in this *** results indicate the occurrence and extension of hysteresis loops in the rows,and a decrease in compressor stability with increasing ramp *** performance is divided into two phases,stable and limit,based on the ramp ***,the model predictions suggest that a decrease in period length and an increase in Strouhal number lead to improved compressor *** DMD results imply that for compressors with inlet temperature ramp distortion,the increase of high-order modes and oscillations at the rotor tip is always the signal of decreasing stability.

关键词： axial compressor stability small perturbation model inlet temperature ramp distortion harmonic balance method dynamic mode decomposition method

Short-term results in canines of novel stent-graft design for chimney technique in TEVAR

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Journal of Interventional Medicine 2020年第3期3卷 128-131页

作者： Ming Li Chang Shu benhao Xiao Dingxiao Liu Weichang Zhang Department of Vascular Surgery The Second Xiangya HospitalCentral South UniversityChangsha410011China Department of Vascular Surgery Fuwai HospitalChinese Academy of Medical SciencesBeijing100037China Lifetech Scientific Co.Ltd China

Introduction:Parallel stent-stent grafting is a major endovascular technique used to preserve the supra-aortic branches during thoracic endovascular aortic repair(TEVAR)of aortic pathologies involving the aortic *** short-and mid-term results of this technique are satisfactory;however,endoleak remains a major ***,here we designed a new chimney stent-graft to decrease the endoleak ***:To testify the feasibility and safety of the new chimney stent-graft system in a canine *** and methods:Six Labrador retrievers were ***-operative data were collected and all operations were performed under general *** main and chimney stent-grafts were implanted through the abdominal aorta and left subclavian artery approaches,*** digital subtraction angiography(Dsa)was performed to confirm the immediate *** dogs were fed separately for 6 months and sacrificed after aortic *** thoracic aorta and the main and chimney stent-grafts were harvested for histopathologic ***:No complications were found in follow-up *** branch arteries were ***?ammatory responses were observed around the stent-grafts in 3 experimental animals,and slight hyperplasia was observed in the surrounding tissues compared with the normal *** was no mural thrombus in the stent,endothelial cells were noted on the inner surface of the stent,and thrombus was formed in the outer skirt and gutter *** histopathologic examinations revealed similar results to those of gross necropsy ***:This study demonstrated the feasibility and safety of the Longuette stent-graft and the first to report a revised stent-graft specific for chimney technique.

关键词： Thoracic endovascular aortic repair Chimney technique Canine model In vivo experiment Stent-graft

Effect of orthokeratology on precision and agreement assessment of a new sweptsource optical coherence tomography biometer

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Eye and Vision 2020年第1期7卷 119-127页

作者： Bao Shu Fangjun Bao Giacomo savini Weicong Lu Ruixue Tu Haisi Chen benhao Song Qinmei Wang Jinhai Huang School of Ophthalmology and Optometry and Eye Hospital Wenzhou Medical University270 West Xueyuan RoadWenzhou 325027ZhejiangChina Key Laboratory of Vision Science Ministry of HealthWenzhouZhejiangPeople’s Republic of China G.B.Bietti Foundation IRCCS RomeItaly

Background:To evaluate the effect of orthokeratology on precision of measurements in children using a new swept-source optical coherence tomography(SS-OCT)optical biometer(OA-2000),and agreement between its measurements and those provided by the commonly used IOLMaster based on partial coherence interferometry(PCI).Methods:This study recruited fifty-one eyes of 51 normal children(8–16 years).An operator took measurements with the two ***,a second operator took measurements with the SS-OCT *** orthokeratology was performed for one month,the same operators repeated the same *** length(AL),mean keratometry(Km)at 2.5 mm and 3.0 mm diameters(Km2.5 and Km3.0),central corneal thickness(CCT),anterior chamber depth(ACD),lens thickness(LT)and corneal diameter(CD)were ***:With the SS-OCT optical biometer,the test-retest repeatability of AL measurements was*** 95%limits of agreement of difference between the two devices for CD parameter were up to 1.53 *** orthokeratology,the fluctuation ranges of difference for Km3.0 measurement was 1.11 times higher than before orthokeratology,while the absolute values of difference for AL,Km2.5,ACD and CD measurements were ***:Before and after orthokeratology,the SS-OCT biometer showed high repeatability and reproducibility for all *** orthokeratology contact lenses affected the agreement between SS-OCT and PCI biometers for Km3.0 *** CD measurement showed poor agreement between the two devices.

关键词： Swept source optical coherence tomography Orthokeratology Precision Agreement Children