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Trajectory Analysis of Fuel Injection into Supersonic Cross Flow Based on Schlieren Method

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Chinese Journal of Aeronautics 2012年第1期25卷 42-50页

作者： YANG hui li feng SUN Baigang School of Jet Propulsion Beihang University Beijing 100191 China

Trajectory analysis of fuel injection into supersonic cross flow is studied in this paper. A directly-connected wind tunnel is constructed to provide stable supersonic freestream. Based on the test rig, the schlieren system is established to reveal the fuel injection process visually. Subsequently, the method of quantitative schlieren is adopted to obtain data of both fuel/air interface and bow shock with the aid of Photoshop and Origin. Finally, the mechanism based on two influential factors of fuel injection angle and fuel injection driven pressure, is researched by vector analysis. A dimensionless model is deduced and analyzed. The curve fitting result is achieved. The relationship between the data and the two influential factors is established. The results provide not only the quantitative characteristics of the fuel injection in supersonic cross flow but also the valuable reference for the future computational simulation.

关键词： fuel injection schlieren supersonic flow injection driven pressure injection angle characteristic velocity

Asymptotic Weighted-Periodicity of the Impulsive Parabolic Equation with Time Delay

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Acta Mathematicae Applicatae Sinica 2007年第1期23卷 1-8页

作者： Jin-liang Wang hui-feng li Ocean Current and Wave Lab Institute of Oceanology Chinese Academy of Science Qingdao 266071 China College of Science Qingdao Technological University Qingdao 266033 China

The main aim of this paper is to investigate the effects of the impulse and time delay on a type of parabolic equations. In view of the characteristics of the equation, a particular iteration scheme is adopted. The results show that Under certain conditions on the coefficients of the equation and the impulse, the solution oscillates in a particular manner--called ＂asymptotic weighted-periodicity＂.

关键词： Weighted-periodicity oscillation impulsive time delay parabolic

The Effect of Method of Constructing the Mass Distribution on Single Stellar Populations

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Chinese Journal of Astronomy and Astrophysics 2005年第4期5卷 371-378页

作者： feng-hui Zhang li-Fang li Zhan-Wen Han National Astronomical Observatories Yunnan Observatory Chinese Academy of SciencesKunming 650011

We use two methods of constructing the initial mass distribution, the traditional way and Monte Carlo simulation, to obtain integrated U - B, B - V,V-R and V-I colours and absorption-line indices defined by the lick Observatory image dissector scanner （referred to as lick/IDS）, for instantaneous burst solarmetallicity single stellar populations with ages in the range 1-15Gyr. We find that the evolutionary curves of all colours obtained by the traditional method are smoother than those by Monte Carlo simulation, that the U- B and B- V colours obtained by the two methods agree with one another, while the V - R and V - I colours by the traditional method are bluer than those by Monte Carlo simulation.A comparison of the lick/IDS absorption-line indices shows that the variations in all the indices by the traditional method are smoother than that for the Monte Carlo simulation, and that all the indices except for TiO1 and TiO2 are consistent with those for the Monte Carlo simulation.

关键词： star: evolution - galaxies: star clusters- galaxies: stellar content

Study of oxidic and sulfded selective hydrodesulfurization catalysts for gasoline using Raman spectroscopy

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Chinese Chemical Letters 2013年第12期24卷 1041-1044页

作者： hui Yuan Qiherima Guang-Tong Xu hui-feng li li-Jun Lu Research Institute of Petroleum Processing SINOPEC The Institute for Chemical Physics Beijing Institute of Technology Inner Mongolia Medical College

A series of CoMo/Al2O3 catalysts for selective hydrodesulfurization （HDS） of gasoline were studied with Raman spectroscopy, a powerful method that creates specific signals for the states and the distributions of oxidic precursors and sulfided active phases. The higher the Mo and Co, the lower the tetrahedrally coordinated molybdate, and the higher the polymolybdate. But the amount of polymolybdate decreased when CoMoO4 appeared. Cobalt-promoted polymolybdate was the precursor, and its relative content correlated well with the HDS selectivity. For sulfided catalysts, adding the cobalt-promoter led to local distortion-disorder of the MoS2 structure and the formation of a CoMoS phase. This method can provide important information for designing new industrial selective-HDS catalvsts.

关键词： Raman spectroscopy Co-Mo/Al2O3 HDS selectivity

Investigation on the active phase of CoMo catalyst for selective HDS by low temperature in situ FT-IR

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Chinese Chemical Letters 2011年第3期22卷 366-369页

作者： Qiherima hui Yuan hui feng li Yun Hong Zhang Guang Tong Xu The Institute for Chemical Physics Beijing Institute of Technology Beijing 100081 China Research Institute of Petroleum Processing SINOPEC Beijing 100083 China Department of Pharmacy Inner Mongolia Medical College Hohhot 010059 China

The CoMo/Al2O3 catalysts with different metal loading were studied by low temperature in situ FT-IR using CO as probe molecule which appears to be a powerful method by giving rise to signals specific for unpromoted and promoted Mo *** result revealed that the increase of CoMoS phase on the catalyst surface improves the HDS activity and *** ratio of active site number of CoMoS and MoS_2 correlates linearly with HDS selectivity,which provides an effective tool for developing industrial selective HDS catalysts.

关键词： FT-IR CO CoMoS HDS selectivity

Gamma-aminobutyric acid promotes human hepatocellular carcinoma growth through overexpressed gamma-aminobutyric acid A receptor α3 subunit

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World Journal of Gastroenterology 2008年第47期14卷 7175-7182页

作者： Yan liu Yue-hui li feng-Jie Guo Jia-Jia Wang Rui-li Sun Jin-Yue Hu Guan-Cheng li Tumor ImmunobiologyLaboratory of Cancer Research Institute Central SouthUniversity Chan~sha 410078 Hunan Province. China

AIM:To investigate the expression pattern of gamma-aminobutyric acid A(GABAA) receptors in hepatocellular carcinoma(HCC) and indicate the relationship among gamma-aminobutyric acid(GABA),gamma-aminobutyric acid A receptor α3 subunit(GABRA3) and ***:HCC cell line Chang,HepG2,normal liver cell line L-02 and 8 samples of HCC tissues and paired non-cancerous tissues were analyzed with semiquantitative polymerase chain reaction(PCR) for the expression of GABAA ***2 cells were treated with gamma-aminobutyric acid(GABA) at serial concentrations(0,1,10,20,40 and 60 μmol/L),and their proliferating abilities were analyzed with the 3-(4,5-methylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay,cell doubling time test,colon formation assay,cell cycle analysis and tumor planted in nude *** interfering RNA was used for knocking down the endogenous GABRA3 in *** abilities of these cells treated with or without GABA were ***:We identified the overexpression of GABRA3 in HCC *** of endogenous GABRA3 expression in HepG2 attenuated HCC cell growth,suggesting its role in HCC cell *** determined the in vitro and in vivo effect of GABA in the proliferation of GABRA3-positive cell lines,and found that GABA increased HCC growth in a dose-dependent ***,the addition of GABA into the cell culture medium promoted the proliferation of GABRA3-expressing HepG2 cells,but not GABRA3-knockdown HepG2 *** means that GABA stimulates HepG2 cell growth through ***:GABA and GABRA3 play important roles in HCC development and progression and can be a promising molecular target for the development of new diagnostic and therapeutic strategies for HCC.

关键词： Hepatocellular carcinoma Proliferation Gamma-aminobutyric acid Gamma-aminobutyric acid A receptor a3 subunit RNAi

Phase Separation Process at Early Aging Stage of Ni42CrTiAl

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材料热处理学报 2004年第5期25卷 191-194页

作者： Weiying-hui Houli-feng Jiaoshao-yang Hulan-qing Xubing-she TaiyuanUniversityofTechnology TaiyuanChina

Phase separation process of Ni42CrTiAl alloy aged at various temperatures was studied by means of transmission electron microscope and X-ray diffraction. It was concluded that the temperature of spinodal decomposition is 500 °C. And the solid solution break into the lean and the rich areas, moreover the rich solute areas would have ordering arrangement to form ordering phase.

关键词：旋节线分析有序化相位变换 Ni42CrTiAl合金

基于RSM的呼吸性粉尘旋风分离器分离效能数值模拟研究

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煤炭学报 2015年第7期40卷 1692-1697页

作者：惠立锋中煤科工集团重庆研究院有限公司重庆400037 瓦斯灾害监控与应急技术国家重点实验室重庆400039

为研究满足BMRC曲线的呼吸性粉尘旋风分离器,利用流体力学软件Fluent 6.3对不同结构尺寸旋风分离器内部流场进行数值模拟,并基于响应曲面法、利用统计软件Design-Expert得到了呼吸性粉尘旋风分离器分离效能二次多项式预测模型。通过方... 详细信息

为研究满足BMRC曲线的呼吸性粉尘旋风分离器,利用流体力学软件Fluent 6.3对不同结构尺寸旋风分离器内部流场进行数值模拟,并基于响应曲面法、利用统计软件Design-Expert得到了呼吸性粉尘旋风分离器分离效能二次多项式预测模型。通过方差分析及回归方程系数显著性检验可知呼吸性粉尘旋风分离器筒体高度、排气管直径及插入深度对其分离效能有显著影响。根据预测模型加工旋风分离器样件并作实测验证,发现样件分离效能与BMRC曲线标准差为3.16%,小于5%。使用响应曲面法研究呼吸性粉尘旋风分离器分离效能可提高设计效率,保证计算模型可靠性,同时为满足EN481,PM10及PM2.5分离器的设计提供参考。

关键词：呼吸性粉尘旋风分离器响应曲面法分离效能

Comparison of the autofluorescence bronchoscope and the white light bronchoscope in airway examination

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Chinese Journal of Cancer 2010年第12期29卷 1018-1022页

作者： Yun li Xiao li Xi-Zhao Sui liang Bu Zu-li Zhou Fan Yang Yan-Guo liu hui Zhao Jian-feng li Jun liu Guan-Chao Jiang Jun Wang Department of Thoracic Surgery People's Hospital Peking University Beijing 100044 P. R. China

Background and Objective: The sensitivity and accuracy of white light bronchoscopy (WLB) in airway examination are low. Autofluorescence bronchoscope (AFB) can determine early lesions in bronchial mucosa more sensitively, but it has seldom performed in China. To assess the clinical value of the AFB in airway examination, we compared the sensitivity and specificity of the AFB and WLB in detecting cancer of the airway mucosa. Methods: Between September 2009 and May 2010, bronchoscope examinations using both the AFB and WLB were performed on 136 patients, 95 men and 41 women with a median age of 61.5 years (ranged from 25 to 84 years). There were 46 lesions located in the central airway, 84 in the peripheral lung parenchyma, and 6 in the mediastinal region. All patients received local and general anesthesia and were subsequently examined with the WLB and AFB in tandem. All procedures were completed safely. Abnormal visual findings were recorded, and biopsies of the affected regions were collected for pathologic examination. Results: Of 241 regions sampled for biopsy, 76 sites contained malignant lesions, whereas 165 sites contained benign lesions. The AFB detected 72 of the 76 malignant lesions, but the WLB detected only 50. The sensitivities of the AFB and WLB were 94.7% and 65.8%, respectively, and the specificities were 57.0% and 83.6%, respectively. The negative predictive values of the AFB and WLB were 95.9% and 84.1%, respectively. Conclusions: The AFB is more sensitive than the WLB in detecting cancerous lesions in the mucosa, and is an effective airway examination.

关键词：病理检查支气管气道萤光自体检测灵敏度空军基地色光