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Chinese Physics B 2019年第2期28卷 241-246页

作者： Li Jiang Ren-gang wan Department of Physics Changchun University of Science and Technology School of Physics and Information Technology Shaanxi Normal University

The absorption–dispersion properties of a microwave-driven five-level atom embedded in an isotropic photonic bandgap(PBG) have been studied. Due to the singular density of modes(DOM) in the isotropic PBG and the dynamically coherence induced by the coupling fields, modified reservoir-induced transparency and quantum interference-induced transparency emerge simultaneously. Their interaction leads to ultra-narrow spectral structure. As a result of closed-loop configuration, these features can be manipulated by the amplitudes and relative phase of the coherently driven fields. The position and width of PBG also have an influence on the spectra. The theoretical studies can provide us with more efficient methods to control the atomic absorption–dispersion properties, which have applications in optical switching and slow light.

关键词： isotropic photonic bandgap absorption–dispersion spectra phase and amplitude control ultranarrow spectral structure

Numerical Investigation on Wet Steam Non-equilibrium Condensation Flow in Turbine Cascade

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Journal of Thermal Science 2012年第6期21卷 525-532页

作者： JU Feng-ming YAN Pei-gang HAN wan-jin School of Energy Science & Engineering Harbin Institute of Technology Harbin 150001 China

Based on the two-phase wet steam flow with spontaneous condensation, experimental verification and flow analysis on nozzle and 2D cascade are carried out. The 3D Reynolds-Averaged gas-liquid two-phase flow control equation solver is explored with k-e-kp turbulence model. Furthermore, 3D flow numerical simulation on the last stage stator of the steam turbine is carried out. The results show that a sudden pressure rise on blade suction surface is mainly caused by the droplet growth in condensation flow. The more backward the condensation position is in cascade passage, the less the sudden pressure rise from condensation is, and the larger the nucleation rate is, the maximum under-cooling and the number of droplets per unit volume are. Interaction of condensation wave and shock wave has imposed greater influence on the parameters of the blade cascade outlet.

关键词： turbine cascade wet steam non-equilibrium condensation two-phase flow

Numerical simulation on the pressure wave in a 30 mm electrothermal-chemical gun with the discharge rod plasma generator

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Defence Technology（防务技术） 2019年第5期15卷 674-679页

作者： Yan-jie Ni Yong Jin gang wan Bao-ming Li National Key Laboratory of Transient Physics Nanjing University of Science and TechnologyNanjing 210094JiangsuChina China Academy of Ordnance 100089BeijingChina

An axisymmetric two-dimensional(2D)internal ballistic model including the transient burning rate law is used to simulate the 30mm electrothermal-chemical(ETC)launch with the discharge rod plasma generator(DRPG).The relationship between the pressure wave and the initial parameters,such as input electric power,discharging timing sequence,loading density and propellant web thickness,is researched through the change of initial parameters in the *** the condition of synchronous discharging,the maximum of the pressure wave can be controlled while the ratio of the input electric energy to the propellant chemical energy(electric energy ratio)is less than *** the electric energy ratio is larger than 0.11,the maximum of the pressure wave increases rapidly with the electric energy *** the increasing of the electric energy ratio,the change of the first negative amplitude value can be *** the condition of timing sequence discharging,the allowed input electric energy ratio to control the pressure wave is proportional to the current pulse *** the high electric energy ratio,the maximum of the pressure wave is inverse proportional to the current pulse *** pressure wave increases with the increasing of the loading *** the allowed electric energy ratio to control the pressure wave and the variation trend of the first negative amplitude wave value doesn't *** the discharging of the DRPG,the influence of changing propellant web thickness in ETC launch can be ignored.

关键词： Electrothermal-chemical launch Pressure wave Plasma Solid propellant Electric energy ratio

From Zn-Al layered double hydroxide to ZnO nanostructure:Gradually etching by sodium hydroxide

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Chinese Chemical Letters 2012年第12期23卷 1415-1418页

作者： gang Qiang wan Dong Xiang Li Chun Fang Li Jie Xu wan Guo Hou State Key Laboratory Base of Eco-chemical Engineering Lab of Colloids and Functional NanostructuresCollege of Chemistry and Molecular EngineeringQingdao University of Science and Technology Key Laboratory of Colloid and Interface Chemistry of Ministry of Education Shandong University

Zn-Al layered double hydroxide （LDH） was used as precursor to produce ZnO nanostructures through dissolution of aluminum hydroxide in caustic soda. The Zn-Al LDH could transform into different nanostructures of ZnO on LDH nanosheets and even pure ZnO nanorods under various NaOH concentration. The formed ZnO nanorods vertically aligned on both LDH sides. UV-vis diverse reflectance spectra show that the obtained ZnO nanorods have a band gap of approximately 3.05 eV. Such ZnO/LDH nanostructures might be used as photocatalyst in the organic pollutant decomposition.

关键词： Layered double hydroxide (LDH) ZnO Nanostructure

CLDASSD:Reconstructing Fine Textures of the Temperature Field Using Super-Resolution Technology

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Advances in Atmospheric Sciences 2022年第1期39卷 117-130页

作者： Ruian TIE Chunxiang SHI gang wan Xingjie HU Lihua KANG Lingling GE Institute of Aerospace Information Space Engineering UniversityBeijing 101400China National Meteorological Information Center China Meteorological AdministrationBeijing 100081China

Before 2008,the number of surface observation stations in China was ***,the surface observation data were too sparse to effectively support the High-resolution China Meteorological Administration’s Land Assimilation System(HRCLDAS)which ultimately inhibited the output of high-resolution and high-quality gridded *** paper proposes a statistical downscaling model based on a deep learning algorithm in super-resolution to research the above ***,we take temperature as an *** model is used to downscale the 0.0625°×0.0625°,2-m temperature data from the China Meteorological Administration’s Land Data Assimilation System(CLDAS)to 0.01°×0.01°,named *** performed quality control on the paired data from CLDAS and HRCLDAS,using data from 2018 and *** was trained on the data from 31 March 2018 to 28 February 2019,and then tested with the remaining ***,extensive experiments were conducted in the Beijing-Tianjin-Hebei region which features complex and diverse *** the HRCLDAS product and surface observation data as the"true values"and comparing them with the results of bilinear interpolation,especially in complex terrain such as mountains,the root mean square error(RMSE)of the CLDASSD output can be reduced by approximately 0.1℃,and its structural similarity(SSIM)was approximately 0.2 *** can estimate detailed textures,in terms of spatial distribution,with greater accuracy than bilinear interpolation and other sub-models and can perform the expected downscaling tasks.

关键词： statistical downscaling deep learning temperature field high-resolution reconstruction

Method of ballistic control and projectile rotation in a novel railgun

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Defence Technology（防务技术） 2018年第5期14卷 628-634页

作者： Bo Tang Ying-tao Xu gang wan Jiang Yue Yong Jin Hai-yuan Li National Key Laboratory of Transient Physics Nanjing University of Science and Technology

In order to realize the ballistic control of the railgun and the flight stability of the projectile, a new type of railgun is designed, which can control the muzzle velocity and rotation rate. The method of the muzzle velocity and overload control is to adjust the voltage or other parameters of pulse power supply. It would be easy to change velocity accurately in large wide. Another widespread concern problem is launching the spinning stability projectile by railgun. This paper designed a new structure of additional rails to generate an unsymmetrical magnetic field to produce rotational torque in armature. The structure is simple and can control the rotation rate by linear changing the barrel parameters. The calculation formulas of interior ballistic are derived by Biot-Safar law. The important parameter is the deflection angle of the additional rails relative to the symmetry plane of main rail. The larger the angle, the greater the rotation torque generated in the armature. To maintain the flight stability of the projectile, the barrel structural parameters should be proportional to the projectile structural parameters. When changing the muzzle velocity, the rotation rate will also be the equal proportion change. So that the gyro stability is the same. The experiment proves that the railgun designed in this paper can launch the projectile to rotate. And the rotational projectile may not cause the transition or much arcs. This method expands the application of the railgun.

关键词： Ballistic control Railgun Rotation Spin-stabilized projectile

A longitudinal study of PSA and its influential factors in a cohort of Chinese men with initial PSA levels less than 4 ng ml-1

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Asian Journal of Andrology 2013年第4期15卷 483-486,I0007页

作者： Ming Liu Jian-Ye wang Hong-Xue Su gang wan Ling Zhu Xiao-Ming wang Beijing Hospital Department ot Urology Belling 100730 China

To evaluate the longitudinal change in prostate-specific antigen （PSA） and the influence of initial PSA on the PSA change. We retrospectively analysed health examination data collected at Beijing Hospital from March 2007 to November 2011. Men with an initial PSA levels less than 4 ng ml- 1 and an annual PSA test for 5 years were enrolled into the study. The men were separated into four groups by the initial PSA level （0-0.99, 1-1.99, 2-2.99 and 3-3.99 ng ml- 1）, and the difference in PSA change among the four groups was analysed. A total of 1330 men were enrolled into the study. The mean age, initial PSA and PSA velocity （PSAV） were 58.17± 14.63 （range 24-91） years, 1.18±0.79 （range 0-4） ng m1-1 and 0.04±0.25 （range -1.34±2.02） ng m1-1 year-1, Pearson＇s correlation analysis showed no correlation between initial PSA and PSAV （r=-0.036, P=0. 189）. The PSAV of the 0-0.99, 1-1.99, 2-2.99 and 3-3.99 ng m1-1 initial PSA groups was 0.03±0.11, 0.07±0.32, 0.03±0.34 and -0.01±0.43 ng m1-1 year-1, respectively （P=0.06）. As the initial PSA increased, the percentage of having a PSAV over 0.75 ng m1-1 year-1 and a negative PSAV both significantly increased. Males with a baseline PSA of 0-0.99, 1-1.99, 2-2.99 and 3-3.99 ng ml- 1 had a 1.88%, 6.16%, 16.30% and 57.81% chance, respectively, that their PSA would increase above 4.0 ng ml- 1 over the following 4 years （P〈0.0001）. The PSAV has no correlation with the initial PSA level. However, as the initial PSA increases, the chance that males will have an abnormal PSA or PSAV in the future increases.

关键词： male prostate cancer (PCa) prostate carcinoma tumour antigen prostate-specific antigen (PSA) PSA velocity

Creating a High-Quality S＆T Innovation Engine

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Qiu Shi 2018年第3期10卷 94-100页

作者： wan gang Vice Chairman of the 13th National Committee of the Chinese People's Political Consultative Conference President of the China Association for Science and Technology and former Minister of Science and Technology of the People's Republic of China

PROMOTE HIGH-LEVEL OPENING AND COOPERATION AND CONTRIBUTE CHINA'S SCIENCE AND TECHNOLOGY TO BUILDING A HUMAN COMMUNITY WITH A SHARED FUTURE

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China News Release 2022年第2期 44-49页

作者： wan gang 不详

The year 2021 marked the centenary of the Communist Party of *** the strong leadership of the Party,China has created two miracles in the world,namely rapid economic growth and long-term social *** has made historic achievements in science and technology,from its humble beginnings to the forefront of science and technology in the world,demonstrating the advantages of the Chinese *** Secretary Xi Jinping pointed out that science and technology are universal and contemporary,and are the common wealth of humankind.

关键词： stability. contemporary Communist

Application of transient burning rate model of solid propellant in electrothermal-chemical launch simulation

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Defence Technology（防务技术） 2016年第2期12卷 81-85页

作者： Yan-jie NI Yong JIN gang wan Chun-xia YANG Hai-yuan LI Bao-ming LI National Key Laboratory of Transient Physics Nanjing University of Science and Technology

A 30 mm electrothermal-chemical(ETC) gun experimental system is employed to research the burning rate characteristics of 4/7 high-nitrogen solid propellant. Enhanced gas generation rates(EGGR) of propellants during and after electrical discharges are verified in the experiments. A modified 0D internal ballistic model is established to simulate the ETC launch. According to the measured pressure and electrical parameters, a transient burning rate law including the influence of EGGR coefficient by electric power and pressure gradient(dp/dt) is added into the model. The EGGR coefficient of 4/7 high-nitrogen solid propellant is equal to 0.005 MW-1. Both simulated breech pressure and projectile muzzle velocity accord with the experimental results well. Compared with Woodley's modified burning rate law, the breech pressure curves acquired by the transient burning rate law are more consistent with test results. Based on the parameters calculated in the model, the relationship among propellant burning rate, pressure gradient(dp/dt) and electric power is analyzed. Depending on the transient burning rate law and experimental data, the burning of solid propellant under the condition of plasma is described more accurately.

关键词：固体推进剂内弹道模型发射模拟电热化学燃速特性瞬态燃烧速率应用