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Flow Field Characteristics for Parachute-projectile System

Chinese Journal of Mechanical Engineering 2011年第5期24卷 813-819页

作者： ZHU Yong LIU Li wang zhengping School of Aerospace Engineering Beijing Institute of Technology Beijing 100081 China

In the current research for parachute flow field nowadays,the size of parachutes in previous research are so large compared with their carriers that the effects of the carriers wake flow to parachute are always *** from such large parachutes,the parachute size in this paper is on the same magnitude with the carrier,thus,the carrier can obviously affect the parachute flow *** this paper,flow field characteristics of small parachute for projectile decelerating are researched through two approaches,namely,computational fluid dynamics（CFD） simulation and wind tunnel *** parachutes with various sizes are chosen for ***,the CFD simulation of flow field around these parachutes is carried out,and then the CFD simulation of parachute-projectile systems is *** to the simulation results,the phenomenon is observed that in the simulations of parachutes there are two vortex-rings at the wind shadow of parachutes,however,in the second simulations of parachute-projectile systems,two additional vortex-rings emerge inside the *** to these two inner vortex-rings,the pressure inside parachutes *** a result,the drag of parachute in simulation of parachute-projectile systems is about 20% smaller compared with the prior *** order to verify the numerical results of CFD simulations,wind tunnel tests are *** terms of the data of the wind tunnel tests,the CFD simulation for flow field characteristics is reasonable and *** results of both CFD simulation and wind tunnel tests demonstrated the influence of projectile wake flow to parachute drag can not be neglected if the parachute size is on the same magnitude with *** influence to parachute drag from the ratio of projectile diameter to parachute diameter is also analyzed both in CFD simulations and wind tunnel *** approach combined CFD simulation and wind tunnel tests proposed can be used to guide the design of such parachute whose si

关键词： parachute projectile flow field computational fluid dynamics(CFD) wind tunnel test

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Nd-doped structurally disordered YSr_(3)(PO_(4))_(3) single crystal:Growth and laser performances

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Journal of Rare Earths 2021年第12期39卷 1540-1546,I0004页

作者： Guangda Wu Xiaoqin Yin Mengdi Fan Fapeng Yu Shuzhen Fan zhengping wang Xian Zhao State Key Laboratory of Crystal Materials Institute of Crystal MaterialsShandong UniversityJinan 250100China Center for Optics Research and Engineering Key Laboratory of Laser&Infrared System(Shandong University)Ministry of EducationQingdao 266200China

Disordered-structure crystals have drawn increasing attention as promising ultrashort laser material hosts owing to their broad ***,a novel disordered Nd:YSr_(3)(PO_(4))_(3)(Nd:YSP)crystal with good quality was successfully grown via the Czochralski pulling *** absorption and fluorescence spectra of the Nd:YSP single crystal were recorded at ambient *** maximum absorption cross section for Nd:YSP single crystal is found to be approximately 3.89×10^(-20) cm^(2).The stimulated emission cross section for Nd:YSP crystal at~1060 nm was determined to be 7.64×10^(20) cm^(2) with the full width half maximum value of 22 *** fluorescence lifetime of the Nd3+ions in the Nd:YSP crystal is fitted to be 288μ***-pumped continuous-wave laser operation is firstly realized at approximately 1060 *** maximum output power value from the Nd:YSP crystal is 714 mW,corresponding to a slope efficiency of-12.8%.The results indicate that the Nd:YSP crystal with a disordered structure may be a promising disordered laser host.

关键词： Crystal growth Thermal behavior Spectral property Laser performance Rare earths

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Passively Q-switched self-frequency doubling Nd3+:ReCa4O（BO3）3（Re=Y,Gd） lasers with tin diselenide as a saturable absorber

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Chinese Optics Letters 2019年第6期17卷 45-48页

作者： Yuxiang Sun Mengxia wang Xinle wang Ying Zhou Bo wang zhengping wang Fapeng Yu Xinguang Xu State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100China Key Laboratory of Functional Crystal Materials and Device (Shandong University) Ministry of EducationJinan 250100China

With tin diselenide(SnSe2)film as a saturable absorber(SA),the passively Q-switched self-frequency doubling(SFD)lasers were realized in Nd^3+:ReCa4O(BO3)3(Re=Y,Gd)*** Nd:YCa4O(BO3)3 crystal,the maximum average output power at 532 nm was 19.6 mW,and the corresponding pulse repetition frequency,pulse duration,single pulse energy,and peak power were 17.6 kHz,91.9 ns,1.1μJ,and 12.1 W,*** Nd:GdCa4 O(BO3)3 crystal,these values were 14.5 mW,22.1 kHz,48.7 ns,0.66μJ,and 13.5 W.

关键词： With tin diselenide the passively Q-switched ,0.66μJ,and 13.5 W.

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The Significance of Ultrasound Findings in Female Adnexal Tumor of Probable Wolffian Origin (FATWO): Case Review Series

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Open Journal of Obstetrics and Gynecology 2020年第8期10卷 990-999页

作者： Jiamin Luo zhengping wang Department of Ultrasound Women’s Hospital School of Medicine Zhejiang University Hangzhou China

Background: Kariminejad and Scully reported 9 cases that were difficult to identify outside the ovary Tumors, located in the broad ligament, fallopian tube mesentery, and ovary, named female adnexal tumors of probable Wolffian origin. Aim: To investigate ultrasound images with female adnexal tumors of probable Wolffian origin (FATWOs). Case Report: We reported ultrasound images in three women with female adnexal tumors of probable Wolffian origin (FATWOs) with detailed discussion. Ultrasonography showed a predominantly-solid mass with clear-cut boundary with neighboring normal ovary at the left mesosalpinx (broad ligament) in both cases. Doppler examination presented moderate color content in both tumors. Conclusion

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Inclusions in DKDP crystal

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Chinese Science Bulletin 2002年第2期47卷 173-176页

作者： Xun Sun Zhangshou Gao Xinguang Xu zhengping wang Jiguo Zhang Yiping Li Zongshu Shao Changshui Fang Shandong Univ State Key Lab Crystal Mat Jinan 250100 Peoples R China

The shape and the size of inclusions in DKDP crystal have been observed and measured microscopically. Three kinds of inclusions were found and the components of the inclusions were measured. The formation mechanisms w... 详细信息

关键词： DKDP crystal microscopy inclusion.

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Analysis of the clinical characteristics and neonatal outcomes of seven cases of pregnancy luteoma discovered incidentally at cesarean section

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Gynecology and Obstetrics Clinical Medicine 2021年第2期1卷 83-86页

作者： Junhua Shen Lanlan Tang Genping Huang Xiaoxia Bai Baohua Li zhengping wang Department of Obstetrics Women’s HospitalZhejiang University School of MedicineXueshi Rd no.1HangzhouZhejiangPR China Department of Pathology Women’s HospitalZhejiang University School of MedicineXueshi Rd no.1HangzhouZhejiangPR China

Objective:In this study,we summarize the clinical characteristics and neonatal outcomes of patients with pregnancy luteomas that were identified incidentally at cesarean section in our *** also provide a review of the existing literature relating to this ***:A total of seven cases of pregnancy luteoma were enrolled from our hospital into this retrospective study between March 2013 and February *** then evaluated the clinical characteristics and neonatal outcomes of these ***:All seven patients with pregnancy luteomas found incidentally during Cesarean sections at term as a result of obstetric *** masses were unilateral and ranged from 2 to 10 cm in *** patients underwent partial ovariectomies or oophorocystectomy due to presumptive benign ovarian *** patients had gestational diabetes and one patient had gestational *** patient developed hirsutism and a deepened *** the seven newborns,three were girls and four were *** examinations of the newborns were normal and no virilization was detected among the infant ***:Pregnancy luteoma may be more common than *** strategies are now needed to educate obstetricians about the clinical features of pregnancy luteoma so that they can avoid unnecessary surgery.

关键词： Pregnancy luteoma Tumor-like ovarian lesion Ovarian tumor Masculinization

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Nodal Type Bound States for Nonlinear Schrodinger Equations with Decaying Potentials

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Journal of Partial Differential Equations 2012年第1期25卷 79-89页

作者： LUO Tingjian wang zhengping Wuhan Institute of Physics and Mathematics Chinese Academy of SciencesP.O.Box 71010Wuhan 430071China

In this paper, we are concerned with the existence of nodal type bound state for the following stationary nonlinear Schrodinger equation -△u（x）＋V（x）u（x）=｜u｜^p-1 u,x∈R^N,N≥3,where 1 〈 p 〈（N＋2）/（N-2） and the potential V（x） is a positive radial function and may decay to zero at infinity. Under appropriate assumptions on the decay rate of V（x）, Souplet and Zhang [1] proved the above equation has a positive bound state. In this paper, we construct a nodal solution with precisely two nodal domains and prove that the above equation has a nodal type bound state under the same conditions on V（x） as in [1].

关键词： Nonlinear Schrodinger equation nodal type bound state decaying potential.

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Nanocrystalline TiO_(2) thin film electrodes prepared by common pressure hydrothermal method at low temperature

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Chinese Science Bulletin 2005年第14期50卷 1449-1452页

作者： LI Chengyu LIN Yuan LI Xueping wang zhengping MA Yutao ZHOU Xiaowen FENG Shujing XIAO Xurui Key Laboratory of Photochemistry Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Chemical College of Harbin Engineering University Harbin 150001 China

Nanocrystalline TiO2 thin film electrodes have been prepared from mixed pastes of tetrabutyl titanate and nanocrystalline TiO2 particles by common pressure hydro- thermal method at low temperature. The tetrabutyl titanate was hydrolyzed and crystallized into anatase TiO2 to inter- connect nanocrystalline TiO2 particles and adhere them to conductive substrates, obtaining highly porous and me- chanically stable TiO2 nanocrystalline film. The conversion efficiencies of the dye-sensitized solar cells based on prepared electrodes on conductive glass substrates and flexible sub- strates were 4.8% and 1.9% under illumination of 100 mW/cm2, respectively.

关键词：二氧化钛薄膜纳米技术低温环境热液压力

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Graphitic carbon nitride, a saturable absorber material for the visible waveband

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Photonics Research 2018年第4期6卷 307-313页

作者： MENGXIA wang FUKUN MA zhengping wang DAWEI HU XINGUANG XU XIAOPENG HAO State Key Laboratory of Crystal Materials Shandong University Research Institute of Science and Technology Shandong University

For the first time to our knowledge, graphitic carbon nitride(g-C_3N_4) nanosheets are found to be an excellent saturable absorber material in the visible waveband. g-C_3N_4 exhibits much stronger saturable absorption in this region than in the near-infrared region, unlike other two-dimensional materials such as graphene and black phosphorus. By the Z-scan method, the nonlinear absorption coefficient β of the material is first measured at three visible wavelengths, and for g-C_3N_4 it is -2.05,-0.34, and -0.11 cm · GW^(-1) at 355, 532, and 650 nm,respectively. These are much larger than -0.06 cm · GW^(-1) at 1064 nm.

关键词：石墨烯氮化物通讯技术材料性能

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Effect　of　Catalyst　Pretreatment　on　the　Oxidation　of　Carbon　Monoxide　over　Gold　Catalysts　Supported　on　Double　Oxides

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分子催化 1997年第2期 4-5页

作者： HAO zhengping AN Lidun 1) wang Hongli (Lanzhou Institute of Chemical physis The Chinese Academy of Scienced Lanzhou 730000)

ＥｆｅｃｔｏｆＣａｔａｌｙｓｔＰｒｅｔｒｅａｔｍｅｎｔｏｎｔｈｅＯｘｉｄａｔｉｏｎｏｆＣａｒｂｏｎＭｏｎｏｘｉｄｅｏｖｅｒＧｏｌｄＣａｔａｌｙｓｔｓＳｕｐｐｏｒｔｅｄｏｎＤｏｕｂｌｅＯｘｉｄｅｓＨＡＯＺｈｅｎｇｐｉｎ... 详细信息

ＥｆｅｃｔｏｆＣａｔａｌｙｓｔＰｒｅｔｒｅａｔｍｅｎｔｏｎｔｈｅＯｘｉｄａｔｉｏｎｏｆＣａｒｂｏｎＭｏｎｏｘｉｄｅｏｖｅｒＧｏｌｄＣａｔａｌｙｓｔｓＳｕｐｐｏｒｔｅｄｏｎＤｏｕｂｌｅＯｘｉｄｅｓＨＡＯＺｈｅｎｇｐｉｎｇＡＮＬｉｄｕｎ１）ＷＡＮＧＨｏｎ...

关键词： Carbon monoxide oxidation Supported gold catalyst Pretreatment

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