The article examines the effect of atomic number, temperature and tempering time on microstructure and mechanical of Ni bulk by molecular dynamics simulation and deformation z-axis. Samples Ni with N = 4000, 5324, 691...The article examines the effect of atomic number, temperature and tempering time on microstructure and mechanical of Ni bulk by molecular dynamics simulation and deformation z-axis. Samples Ni with N = 4000, 5324, 6912, and 8788 atoms at 300 K, 6912 atoms at T = 1100, 900, 700, 500, 300 K and 6912 atoms at 900 K after different annealing time. The samples were incubated with the same heating rate . Combined with common neighborhood analysis method shown in sample is always existing four types structure: FCC, HCP, BCC, and Amor. In particular, structural units FCC, HCP and Amor always prevail and BCC are very small and appear only at 300, 500 K with 6912 atoms. When increasing atomic number, lowering temperature or increasing tempering time will facilitate crystallization process leading to increased FCC and HCP units number. The increasing FCC, HCP units number and additional appearance BCC structure led to change microstructure and mechanical of material: When increasing atom, lowering temperature and increasing incubation time lead to an increase in density of atoms that increase mechanical properties of the material.展开更多
Shear-wave velocity is a key parameter for calibrating monitoring time-lapse 4D seismic data during CO2-EOR （Enhanced Oil Recovery） and CO2 sequestration. However, actual S-wave velocity data are lacking, especially...Shear-wave velocity is a key parameter for calibrating monitoring time-lapse 4D seismic data during CO2-EOR （Enhanced Oil Recovery） and CO2 sequestration. However, actual S-wave velocity data are lacking, especially in 4D data for CO2 sequestration because wells are closed after the CO2 injection and seismic monitoring is continued but no well log data are acquired. When CO2 is injected into a reservoir, the pressure and saturation of the reservoirs change as well as the elastic parameters of the reservoir rocks. We propose a method to predict the S-wave velocity in reservoirs at different pressures and porosities based on the Hertz-Mindlin and Gassmann equations. Because the coordination number is unknown in the Hertz Mindlin equation, we propose a new method to predict it. Thus, we use data at different CO2 injection stages in the Gao89 well block, Shengli Oilfield. First, the sand and mud beds are separated based on the structural characteristics of the thin sand beds and then the S-wave velocity as a function of reservoir pressure and porosity is calculated. Finally, synthetic seismic seismograms are generated based on the predicted P- and S-wave velocities at different stages of CO2 injection.展开更多
为了研究总体理查逊数对可吸入颗粒物PM10(particulate matter with aero-dynamic diameter smaller than 10μm)质量浓度的影响,对2007年11月北京南郊观象台的PM10质量浓度资料、地面气象自动站资料和常规无线电探空资料进行了分析。...为了研究总体理查逊数对可吸入颗粒物PM10(particulate matter with aero-dynamic diameter smaller than 10μm)质量浓度的影响,对2007年11月北京南郊观象台的PM10质量浓度资料、地面气象自动站资料和常规无线电探空资料进行了分析。统计分析软件采用SPSS 15.0(Statistical Package for Social Sciences 15.0)。分析结果表明,在北京地区以稳定层结为主的条件下,PM10质量浓度与地面气象要素和总体理查逊数存在很好的规律性。PM10质量浓度与风速和相对湿度显著相关,相关系数分别为原0.65和0.69,通过α=0.01显著性检验;PM10质量浓度与地面至450m层的总体理查逊数存在显著的对数形式非线性关系,决定系数R2=0.42。非线性回归方程的独立样本预测检验显示回归模型可以用于根据无线电探空资料对PM10质量浓度进行预测。展开更多
基于Hgstrm(1996)和Beljaars et al.(1991)的研究工作,沿用Louis et al.(1982)和Launiainen(1995)的思路,本文采用多元回归分析方法,研发了一种采用非迭代方法的湍流通量参数化方案。该方案直接用整体理查森数、空气动力学粗糙度长...基于Hgstrm(1996)和Beljaars et al.(1991)的研究工作,沿用Louis et al.(1982)和Launiainen(1995)的思路,本文采用多元回归分析方法,研发了一种采用非迭代方法的湍流通量参数化方案。该方案直接用整体理查森数、空气动力学粗糙度长度和热力学粗糙度长度对稳定度参数进行参数化,从而避免了通过循环迭代计算Monin-Obukhov长度。该方案不仅有效地节省了CPU计算时间,而且其计算结果与迭代方案(BHH方案)的计算结果非常接近。展开更多
In this paper,a preliminary study is given on the drag (i.e.bulk transfer for momentum) coefficient,on the basis of data from four sets of AWS in Tibet during the first observational year from July 1993 to July 1994 a...In this paper,a preliminary study is given on the drag (i.e.bulk transfer for momentum) coefficient,on the basis of data from four sets of AWS in Tibet during the first observational year from July 1993 to July 1994 according to China Japan Asian Monsoon Cooperative Research Program.The results show that the drag coefficient over the Tibetan Plateau is 3.3 to 4.4×103.In addition,monthly and diurnal variations of drag coefficient and the relationship among the drag coefficients and the bulk Richardson number,surface roughness length and wind speed at 10 m height are discussed in detail.展开更多
文摘The article examines the effect of atomic number, temperature and tempering time on microstructure and mechanical of Ni bulk by molecular dynamics simulation and deformation z-axis. Samples Ni with N = 4000, 5324, 6912, and 8788 atoms at 300 K, 6912 atoms at T = 1100, 900, 700, 500, 300 K and 6912 atoms at 900 K after different annealing time. The samples were incubated with the same heating rate . Combined with common neighborhood analysis method shown in sample is always existing four types structure: FCC, HCP, BCC, and Amor. In particular, structural units FCC, HCP and Amor always prevail and BCC are very small and appear only at 300, 500 K with 6912 atoms. When increasing atomic number, lowering temperature or increasing tempering time will facilitate crystallization process leading to increased FCC and HCP units number. The increasing FCC, HCP units number and additional appearance BCC structure led to change microstructure and mechanical of material: When increasing atom, lowering temperature and increasing incubation time lead to an increase in density of atoms that increase mechanical properties of the material.
基金supported by the National High Techology Research and Development Program(No.2012AA050103)
文摘Shear-wave velocity is a key parameter for calibrating monitoring time-lapse 4D seismic data during CO2-EOR （Enhanced Oil Recovery） and CO2 sequestration. However, actual S-wave velocity data are lacking, especially in 4D data for CO2 sequestration because wells are closed after the CO2 injection and seismic monitoring is continued but no well log data are acquired. When CO2 is injected into a reservoir, the pressure and saturation of the reservoirs change as well as the elastic parameters of the reservoir rocks. We propose a method to predict the S-wave velocity in reservoirs at different pressures and porosities based on the Hertz-Mindlin and Gassmann equations. Because the coordination number is unknown in the Hertz Mindlin equation, we propose a new method to predict it. Thus, we use data at different CO2 injection stages in the Gao89 well block, Shengli Oilfield. First, the sand and mud beds are separated based on the structural characteristics of the thin sand beds and then the S-wave velocity as a function of reservoir pressure and porosity is calculated. Finally, synthetic seismic seismograms are generated based on the predicted P- and S-wave velocities at different stages of CO2 injection.
文摘为了研究总体理查逊数对可吸入颗粒物PM10(particulate matter with aero-dynamic diameter smaller than 10μm)质量浓度的影响,对2007年11月北京南郊观象台的PM10质量浓度资料、地面气象自动站资料和常规无线电探空资料进行了分析。统计分析软件采用SPSS 15.0(Statistical Package for Social Sciences 15.0)。分析结果表明,在北京地区以稳定层结为主的条件下,PM10质量浓度与地面气象要素和总体理查逊数存在很好的规律性。PM10质量浓度与风速和相对湿度显著相关,相关系数分别为原0.65和0.69,通过α=0.01显著性检验;PM10质量浓度与地面至450m层的总体理查逊数存在显著的对数形式非线性关系,决定系数R2=0.42。非线性回归方程的独立样本预测检验显示回归模型可以用于根据无线电探空资料对PM10质量浓度进行预测。
文摘基于Hgstrm(1996)和Beljaars et al.(1991)的研究工作,沿用Louis et al.(1982)和Launiainen(1995)的思路,本文采用多元回归分析方法,研发了一种采用非迭代方法的湍流通量参数化方案。该方案直接用整体理查森数、空气动力学粗糙度长度和热力学粗糙度长度对稳定度参数进行参数化,从而避免了通过循环迭代计算Monin-Obukhov长度。该方案不仅有效地节省了CPU计算时间,而且其计算结果与迭代方案(BHH方案)的计算结果非常接近。
文摘In this paper,a preliminary study is given on the drag (i.e.bulk transfer for momentum) coefficient,on the basis of data from four sets of AWS in Tibet during the first observational year from July 1993 to July 1994 according to China Japan Asian Monsoon Cooperative Research Program.The results show that the drag coefficient over the Tibetan Plateau is 3.3 to 4.4×103.In addition,monthly and diurnal variations of drag coefficient and the relationship among the drag coefficients and the bulk Richardson number,surface roughness length and wind speed at 10 m height are discussed in detail.
