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Measurement of the Mass Excess of ^(158)Sm

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Chinese journal of nuclear physics 1995年第3期17卷 234-238页

作者： Zhao Kui Guo Ji-yu Lu Xiu-qin cheng Ye-hao Huang Xiao-lin Ma Yong Li Shu-yuan Ruan Ming Li Zhi-chang Jiang cheng-lie China Institute of Atomic Energy,P.O.Box 275(10),Beijing 102413 中国原子能科学院北京

A Q-value of —4.076±0.151 MeV has been determined for the two-proton transfer reaction160Gd(18O,20Ne)158Sm,which yields a first experimental measured value of —65.764±0.151 MeV forthe mass excess of 158Sm,the nucl... 详细信息

关键词： Heavy ion reaction Q-value Mass excess

Weakening the conservativeness of the Min-Max control structure of aero-engine:a coordination function method based on safety margin

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Weakening the conservativeness of the Min-Max control struct...

第43届中国控制会议

作者： Zhang cheng Xue yu Liu Shuai College of Aeronautical Engineering Civil Aviation University of China

In order to solve the conservative problem of the existing Min-Max control structure,this paper proposes a coordination function method based on safety margin to give full play to the engine's potential in output *** defining the concept of safety margin,the coordination relationship between the performance and limit protection parameters in the transition process is analyzed,and the conservatism is described ***,the concept of safety margin is ***,the influence of performance parameters on the safety margin of each limit protection parameter is ***,a coordination function method based on safety margin is designed and *** basic idea of this method is to judge the safety margin of the engine limit protection parameters by improving the existing Min-Max control structure and using the coordination function to guide the linear controller of each limit protection parameter to change the control gain and control the current working state of the *** simulation results show that this method can reduce the conservatism of the existing Min-Max control structure,improve the response speed of the fan speed,ensure that the aero-engine has a higher thrust response speed,and optimize the transition state performance of the aero-engine under the condition that the engine limit protection parameters are not exceeded.

关键词： Aero-engine Min-Max control structure Conservatism Safety margin Coordination function

Modeling of shell-mixing into the central hotspot in inertial confinement fusion implosion

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Modeling of shell-mixing into the central hotspot in inertia...

2016第八届全国计算物理会议

作者： yu cheng-xin FAN Zheng-feng Institute of Applied Physics and Computational Mathematics

Starting from the mass conservation and energy conservation of hotspot,the dynamics of hotspot combustion involving shell-mix are constructed by recalculating the special internal energy and heat capacity,in which the bremsstrahlung radiation loss and other energy transfer are *** the power balance in the hotspot,the relations between the fractions of shell-mixing in the hotspot and the ignition threshold and self-sustainable combustion are *** theoretical analysis and numerical simulation show that the enhancement of radiation loss induced by the shell-mixing plays the dominated role in the failure of *** adjusting different materials and the mixing fraction,the effects to the combustion paths are studied.

关键词： Inertial confinement fusion Implosion mixing Hotspot combustion Degradation of shell-mixing

Boundary control for stochastic nonlinear heat equation with and without time delay

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Boundary control for stochastic nonlinear heat equation with...

第43届中国控制会议

作者： yu-Shuo Shang Hua-cheng Zhou School of Mathematics and Statistics HNP-LAMA Central South University

In this paper, we consider boundary stabilization for stochastic nonlinear heat equations with and without time *** backstepping approach is adopted in the investigation. We first design a boundary controller for stochastic nonlinear heat equation without time delay and derive a criterion under which the controlled system achieves mean square exponential stability,utilizing the Lyapunov functional method, stochastic analysis technique and Wirtinger's inequality. Secondly, we propose a stabilizing boundary controller for stochastic nonlinear heat equation with time delay and show its closed-loop system to be mean square exponentially stable. Some numerical simulations are presented to validate the results.

关键词： Boundary control Backstepping Stochastic heat equation Time delay Stabilization

Off-pump sequential bilateral internal mammary artery grafting combined with selective arterialization of the coronary venous system

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Chinese Medical Journal 2011年第19期124卷 3017-3021页

作者： yu Yang YAN Xiao-lei WEI Hua YANG Jun-feng GU cheng-xiong Department of Cardiac Surgery Beijing An Zhen Hospital Capital Medical University Beijing 100029 China

Background Off-pump coronary artery bypass surgery （OPCAB） has been widely applied in recent years as a less invasive method of myocardial revascularization. This study evaluated the sequential bilateral internal mammary artery grafting combined with selective arterialization of the coronary venous system during *** From April 2004 to August 2010, patients with diffuse right coronary lesions were studied retrospectively and divided into two groups. Group 1 included seventeen patients who underwent this surgery while group 2 included twenty-one patients without right coronary artery surgical therapy. All patients presented with symptoms of angina. Blood flow of bridged vessels was measured. The perioperative ventricular parameters including left ventricular ejection fraction and end diastolic diameter were compared. During follow-up, myocardial nuclide imaging and coronary angiography were carried *** Off-pump coronary artery bypass was performed with an average of 3.6 grafts per patient. Hospital mortality was zero. At the time of follow-up, the patients in group 1 recovered better than in group 2 （P〈0.05）. In both groups, the mean New York Heart Association （NYHA） class and ejection fraction increased significantly （P〈0.001） and the mean left ventricular end-diastolic diameter decreased significantly （P 〈0.05）. Myocardial blood supply of inferior wall in group 1 was obviously improved by myocardial nuclide imaging. Coronary angiography for eight patients in group 1 verified that there was blood flow to myocardium in the arterialized *** Sequential bilateral internal mammary artery grafting combined with selective arterialization of the coronary venous system can be performed during OPCAB. A postoperative improvement in the cardiac functions and the quality of life was documented, increasing our expectation for extensive application.

关键词： off-pump coronary artery bypass internal mammary artery," arterialization of the coronary venous system

对-甲苯乙酮与芳香醛和芳香胺的Mannich反应

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高等学校化学学报 2000年第11期21卷 1694-1696页

作者：杨大成章国林杨宇钟裕国西南师范大学化学化工学院重庆400715 浙江大学药学院杭州310031 华西医科大学药学院成都610041

In the presence of catalytical amount of concentrated hydrochloric acid, 4 methylacetophenone can react directly with benzaldehyde, 4 methylbenzaldehyde and some aromatic amines in ethanol solution at 26~32 ℃ to afford 1 (4 methylphenyl) 3 aryl 3 arylamino 1 propanones with 61%~96% yield. There are seven new compounds among the 17 substances prepared. The IR and 1H NMR spectra and elemental analyses of these Mannich bases are given and they are consistent with the structures of these compounds.

关键词： Mannich反应芳香醛芳香胺对-甲苯乙酮

Off-pump surgery for coronary artery disease combined with mitral stenosis

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Chinese Medical Journal 2013年第24期126卷 4807-4808页

作者： LI Hai-tao yu Yang HUANG Xin-sheng GU cheng-xiong Department of Cardiac Surgery Beijing An Zhen Hospital Capital Medical University Beijing 100029 China

Rheumatic heart disease is still highly prevalent in .developing countries where the incidence of coronaryartery disease （CAD） is also arising. Consequently the occurrence of coexistent CAD and mitral stenosis （MS） dominantly caused by rheumatic fever is more frequent in these countries. Comorbidities such as pulmonary and renal dysfunction occur frequently in these aging populations. Off-pump surgery is widely applied in patients with concomitant CAD and severe comorbidities due to lower incidence of postoperative morbidity. Closed mitral commissurotomy （CMC） is a well established treatment for patients with mitral stenosis. We report here a case of moderate stenosis combined with seriously diffuse 3-vessel CAD and severe chronic obstructive pulmonary disease （COPD） in an elder male treated with off-pump coronary artery bypass （OPCAB） plus CMC.

关键词： coronary artery disease, valvular disease, off-pump mitral commissurotomy

Regional Ionospheric TEC Gradients Estimation using A Single GNSS Receiver

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Regional Ionospheric TEC Gradients Estimation using A Single...

第五届中国卫星导航学术年会

作者： cheng Wang Jiexian Wang yu Morton

This paper presents an algorithm to estimate regional ionospheric total electron content （TEC） and TEC gradients. In this study, the ionospheric vertical TEC （VTEC） at an ionosphere piercing point （IPP） in a local area is represented by contributions from the VTEC at other IPPs in the local area and spatial gradients of TEC along both latitudinal and longitudinal directions. By differencing the TEC between each pair of observable IPPs, linear equations of local TEC gradients can be established if only first order and second order TEC spatial derivatives in the TEC representation are retained. The TEC gradients obtained from these linear equations are then combined with VTEC of observable IPPs to generate regional TEC maps. The algorithm is tested using a single GNSS receiver located on the campus of Tongji University over a 24-hour period. The TEC values obtained from the algorithm are compared with that from the polynomial-based regional ionospheric TEC model constructed using data from 13 stations in Yangtze River Delta area and also with estimations generated from the IGS global ionosphere maps （GIM）. The results show that the average difference between TEC values generated from a single receiver using the TEC gradient-based algorithm and from 13 stations using the polynomial-based regional TEC model is around 1 TECU, and the standard deviation of the differences is about 1.5 TECU. Also, the average difference between TEC values calculated from the proposed TEC algorithm and from GIM is about 0.5 TECU, and the standard deviation of the differences is nearly 1.6 TECU. The results demonstrate that the proposed TEC gradient-based method has the potential to produce accurate regional TEC maps for precise positioning and for ionospheric monitoring using measurements from only a single receiver. The algorithm can be easily modified to incorporate other multi-GNSS measurements such as GLONASS, Beidou System and Galileo to further improve precision.

关键词： ionosphere total electron content gradient model

Characteristics and clinical role of bronchoscopy in diagnosis of childhood endobronchial tuberculosis

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World Journal of Pediatrics 2017年第6期13卷 599-603页

作者： An-Xia Jiao Lin Sun Fang Liu Xiao-Chun Rao yu-Yan Ma Xi-cheng Liu Chen Shen Bao-Ping Xu A-Dong Shen Kun-Ling Shen Key Laboratory of Major Diseases in Children Ministry of EducationNational Clinical Research Center for Respiratory DiseasesNational Key Discipline of Pediatrics(Capital Medical University)Department of Interventional PulmonologyBeijing Children's HospitalCapital Medical UniversityNational Center for Children's Health Beijing Key Laboratory of Pediatric Respiratory Infection Diseases Beijing Pediatric Research InstituteBeijing Children's HospitalCapital Medical UniversityNational Center for Children's Health Department of Respiratory Diseases Beijing Children's HospitalCapital Medical UniversityNational Center for Children's Health

Background:Endobronchial tuberculosis (EBTB) is the most frequent complication of primary pulmonary tuberculosis (PTB) in *** aim of the study was to analyze characteristics and clinical role of bronchoscopy in diagnosis of childhood ***:A retrospective,descriptive study was undertaken in 157 children with EBTB undergone flexible bronchoscopy (FB) between January 2006 and June ***:The median age of the enrolled patients was 3.4 years,with 73.2% of patients under five years *** most common subtype was tumorous type (145/157,92.4%).If only involved bronchus were considered,the common affected sites were right middle lobe bronchus (49/228,21.5%),left upper lobe bronchus (41/228,18.0%),right upper lobe bronchus (41/228,18.0%),right main bronchus (35/228,15.4%),*** younger than five years old were at higher risk to have multiple endobronchial lesions (P=0.044),with an odds ratio of 2.313 (95% confidence interval:1.009-5.299).Before the bronchoscopy,only 16 (10.2%)patients were highly suspected of EBTB,while the others were diagnosed as PTB without EBTB (69.4%),or misdiagnosed as pneumonia or foreign body aspiration (20.4%) on ***:The patients under five years old are at high risk to progress to EBTB and have multiple endobronchial *** most frequent subtype of EBTB in children is tumorous *** lesions are seen in the right bronchial system more *** should be performed to detect the endobronchial lesions in suspected patients as soon as possible.

关键词： diagnosis endobronchial tuberculosis flexible bronchoscopy