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Toward 5.2μm terawatt few-cycle pulses via optical parametric chirped-pulse amplification with oxide La3Ga5.5Nb0.5O14crystals

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High Power Laser Science and Engineering 2019年第4期7卷 21-32页

作者： jinsheng liu Jingui Ma Jing Wang Peng Yuan Guoqiang Xie Liejia Qian Key Laboratory for Laser Plasmas(Ministry of Education) Collaborative Innovation Centre of IFSA(CICIFSA)School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

High-power femtosecond lasers beyond 5μm are attractive for strong-field physics with mid-infrared(IR)fields but are difficult to scale *** optical parametric chirped-pulse amplification(OPCPA)at mid-IR wavelengths,a nonlinear crystal is vital,and its transmittance,dispersion,nonlinear coefficient and size determine the achievable power and *** beyond 5μm routinely relies on semiconductor crystals because common oxide crystals are not transparent in this spectral ***,the small size and low damage threshold of semiconductor crystals fundamentally limit the peak power to *** this paper,we design a terawatt-class OPCPA system at 5.2μm based on a new kind of oxide crystal of La3Ga5.5Nb0.5O14(LGN).The extended transparent range,high damage threshold,superior phase-matching characteristics and large size of LGN enable the generation of 0.13 TW seven-cycle pulses at5.2μ*** design fully relies on the state-of-the-art OPCPA technology of an octave-spanning ultrafast Ti:sapphire laser and a thin-disk Yb:YAG laser,offering the performance characteristics of high power,a high repetition rate and a stable carrier-envelope phase.

关键词： few-cycle mid-infrared OPCPA oxide LGN crystals

Prototype of multi-filament electron curtain accelerator

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Nuclear Science and Techniques 2013年第B12期24卷 1-4页

作者： LI Guohua TANG Huaping liu jinsheng ZHANG Huayi liu Yaohong ZHANG Dongsheng HE Yu LI Jian GUAN Weiqiang Division of Accelerator Technology Nuctech Co. Ltd Beijing 100084 China Department of Engineering Physics Tsinghua University Beijing 100084 China

In this paper, we present a prototype of electron curtain accelerator with 200 kV high voltage and an average beam current around 20 mA with beam width about 600 mm. Several physical and mechanical design of this facility is discussed in detail thoroughly, in conjunction with 3D software modeling and simulation. And some efforts to modulate cathode structure have been done to improve the electron beam uniformity effectively. © 2013, Science Press. All rights reserved.

关键词：电子帘加速器原型机械设计软件建模阴极结构高电压均匀性电子束

Insights into the Reaction Network and Mechanism of Green Aerobic Oxidative Esterification of Methacrolein over Different Heterogeneous Catalysts

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China Petroleum Processing & Petrochemical Technology 2021年第3期23卷 1-11页

作者： Li Chenhao Xia Changjiu liu Yujia Huang Kaimeng Peng Xinxin liu jinsheng Lin Min Zhu Bin Luo Yibin Shu Xingtian State Key Laboratory of Catalytic Materials and Reaction Engineering Research Institute of Petroleum ProcessingSINOPECBeijing 100083

The oxidative esterification of methacrolein(MAL)is an important way to prepare high-valued methyl methacrylate(MMA),but this process is ultra-complex due to the high reactivity of both C=O and C=C bonds in MAL *** order to further improve MMA selectivity,the reaction network and relevant mechanisms have been proposed and profoundly investigated in this *** kinds of fundamental reactions are involved in this process,including(a)the acetal reaction;(b)the aerobic oxidation of hemiacetal;(c)the alkoxylation of C=C double bond;(d)the Diels-Alder reaction;and(e)the hydrogenation reaction of unsaturated double *** them,the Diels-Alder reaction of MAL is non-catalyzed,and the Brönsted acid sites or the Lewis acid sites favor promoting acetal reaction of MAL with methanol,while the alkoxylation of C=C bond with methanol is enhanced under alkaline *** particular,by employing the Pd-based catalysts,hydrogenation products are formed in alkaline methanol solution,hence with lower than those obtained by the Au-based ***,it is necessary to match the hemiacetal fromation and aerobic oxidation of hemiacetal,which is relevant with the amount and strength of acid and redox ***,this work can provide a good guidance for the further design of both catalysts and processes in future.

关键词： methacrolein oxidative esterification mechanism reaction network methyl methacrylate

The Column Summation Contrary Method of Calculation Interval Number Weights

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Systems Science and Systems Engineering 1996年第3期6卷 334-336页

作者： liu jinsheng WANG Caixian(Taiyuan University of Technology, Taiyuan 030024, China)

In the uncertain type and group of AHP, the element of judgement matrix can be an interval number. This paper expands the Column Summation Contrary Method (i. e. CSCM) of general AHP, gives the CSCM of calculation interval number weights, discusses the property of rank preservation, illustrates that CSCM is more reasonable and convenient from theory to reality.

关键词： AHP CSCM interval number weight.

Analysis on Well Drilling Example of Deepwater Block in the Gulf of Mexico

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Open Journal of Yangtze Oil and Gas 2021年第4期6卷 191-200页

作者： Yi Zheng jinsheng liu Xiao Wang Mexico Project Team of Oilfield Technology Division of China Oilfield Services Limited Tianjin China Marketing Department of Oilfield Technology Division of China Oilfield Services Limited Tianjin China Shenzhen Operation Company of Oilfield Technology Division of China Oilfield Services Limited Shenzhen China

With the innovation and development of offshore oil drilling technology, drilling wells in deep waters areas have become an important activity for the development of new hydrocarbon reservoirs in this type of environment. CNOOC (China National Offshore Oil Corporation) won the rights to exploit two unexplored deepwater blocks in the Gulf of Mexico, in a bid realized by the Mexican Government (CNH), in 2016. The challenge to combine the newest technology with the oil industry experienced knowledge to lead the exploration and development of these deep-water blocks in Mexico is around the corner. Therefore, the basic techniques for deep waters wells drilling and the main potential risks are expounded in this paper. A set of deep waters wells drilling processes and methodologies are previously designed, and a specific case is demonstrated next, which provides a referential model for deep waters wells drilling in the Gulf of Mexico.

关键词： The Gulf of Mexico Deepwater Drilling Directional Drilling Bottom Hole Assembly (BHA)

Experimental investigation of a seven-element hexagonal fiber coherent array

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Chinese Optics Letters 2010年第1期8卷 48-51页

作者：范馨燕刘京郊刘金生武敬力 National key Laboratory of Tunable Laser Technology Harbin Institute of Technology Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of Sciences

The phase noises of a 10-m polarization-maintaining （PM） fiber and a 10-W PM fiber amplifier are experimentally measured. The results indicate that the 10-m PM fiber with similar phase noise could be used to investigate the architecture of master oscillator power amplifier coherent combination. A seven-element hexagonal fiber coherent array is developed to investigate the far-field distribution and phase controlling technique of a coherently combining fiber laser array. A hexagonal prism is designed as the combining and splitting component to achieve a fill factor of 0.66. The hill climbing method is employed to detect and lock the element phase.

关键词： Fiber amplifiers Phase noise Power amplifiers

Diagnosis and clinical manifestations of subacute combined degeneration of the spinal cord: Analysis of 21 cases

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Neural Regeneration Research 2007年第2期2卷 112-116页

作者： Yanhong Shou Caifeng Li Dongsheng Fan Yang Shen Jun Zhang Weizhong Xiao Shuqing Zhao jinsheng liu Wei Sui Department of Neurology Third Hospital of Peking University Beijing 100083 China Department of Neurology Panshi Boren Hospital Panshi 130021 Jifin Province China

BACKGROUND： Subacute combined degeneration of the spinal cord is caused by vitamin B12 deficiency and is a kind of degenerative disease owing the characteristics of nervous system diseases. In addition, different patients have variously clinical manifestations and various prognoses after vitamin B12 therapy. OBJECTIVE： To investigate and analyze diagnosis, clinical manifestations and prognosis of subacute combined degeneration of the spinal cord. DESIGN： Case analysis. SETTING： Department of Neurology, the Third Hospital of Peking University. PARTICIPANTS： A total of 21 subacute combined degeneration of the spinal cord patients including 14 males and 7 females aged from 33 to 82 years were selected from Department of Neurology, the Third Hospital of Peking University from January 1999 to December 2005. Duration from onset to final diagnosis lasted for 1.5 - 108 months. All patients had typically clinical manifestations; meanwhile, level of serum vitamin B12 was decreased and/or vitamin B12 therapy was effective. All patients provided the confirmed consent. METHODS： Clinical data of 21 subacute combined degeneration of the spinal cord patients were retrospectively analyzed, while general data and clinical characteristics were recorded at the same time. Levels of blood routine, serum vitamin B12 and homocysteine were measured at the phase of hospitalization. Normal value of serum vitamin B12 was 187 - 1 059 ng/L and normal value of serum homocysteine was 5 - 15μ mol/L. All patients received neuroelectrophysiological examination and 15 patients received MRI examinations of spinal cord. After final diagnosis, patients were given vitamin B12 therapy. And follow-up was performed to investigate the prognosis. MAIN OUTCOME MEASURES：（1） Levels of blood routine, serum vitamin B12 and homocysteine; （2） results of neuroelectrophysiological examination; （3） results of MRI examination of spinal cord; （4） prognosis. RESULTS： Clinical data of 21 patients and follow-up data of 20 p

关键词： vitamin B12 deficiency spinal cord diseases diagnosis prognosis

Heparin-free veno-venous extracorporeal membrane oxygenation in non-trauma patients with difficult airways for surgery

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Chinese Medical Journal 2023年第10期136卷 1251-1252页

作者： Hongya Chen jinsheng liu Lili Wu Cunliang Ji Tong Li Guyan Wang Department of Anesthesiology Beijing Tongren HospitalCapital Medical UniversityBeijing 100730China Department of Intensive Care Unit Beijing Tongren HospitalCapital Medical UniversityBeijing 100730China

To the Editor:For patients with critical tracheal stenosis in surgery,extracorporeal membrane oxygenation(ECMO)is probably the last,yet safest,choice to ensure definitive airway *** anticoagulation in the form of heparin is a typical ***,heparin is fraught with its own complications that include both bleeding in the patient and clotting within the circuitry.

关键词： airway surgery patients

TEACHING INTONATION TO CHINESE STUDENTS OF ENGLISH

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Chinese Journal of Applied Linguistics 2000年第2期23卷 31-35页

作者： liu Yunhong Zhang jinsheng PLA Foreign Languages University

In teaching English pronunciation,intonationoften poses difficulties to Chinese *** paperpresents an approach of intonation teaching whichconsists of the following points:1)compare Chineseand English intonation;2)analyze the structure ofEnglish intonation;3)guide practice through imita-tion;4)emphasize the functions of English intona-tion.

关键词： TEACHING INTONATION TO CHINESE STUDENTS OF ENGLISH oral