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燃烧反应机理构建的双参数速率常数方法 被引量:5
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作者 李象远 姚晓霞 +4 位作者 申屠江涛 孙晓慧 李娟琴 刘明夏 许诗敏 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2020年第3期512-520,共9页
采用Arrhenius方程的双参数形式描述反应的速率常数对温度的依赖关系,解决了三参数(A,n,E)过拟合造成的复杂燃烧机理参数缺乏通用性等问题.在不改变物种数和基元反应数条件下,将UCSD核心机理进行双参数处理,并应用于小分子体系的动力学... 采用Arrhenius方程的双参数形式描述反应的速率常数对温度的依赖关系,解决了三参数(A,n,E)过拟合造成的复杂燃烧机理参数缺乏通用性等问题.在不改变物种数和基元反应数条件下,将UCSD核心机理进行双参数处理,并应用于小分子体系的动力学模拟,得到的模拟结果与三参数机理基本相符.双参数机理恢复了Arrhenius活化能的物理意义,可实现机理的参数比较和迁移,缩小了机理整体优化的变量空间,为燃烧机理参数的统一奠定了基础. 展开更多
关键词 燃烧反应机理 速率常数 双参数 数值模拟
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ITO薄膜的透射谱解谱 被引量:2
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作者 郭守月 曹春斌 孙兆奇 《真空科学与技术学报》 EI CAS CSCD 北大核心 2009年第2期180-183,共4页
用直流磁控溅射法在普通载波片上制备了厚度130nm左右的ITO薄膜,分别在100、200、300和400℃下退火1h。测量了退火前后几个样品的XRD和透射率,利用椭偏解谱方法对几个样品的透射谱进行建模及解谱,结果表明,未退火样品为非晶结构,退火后... 用直流磁控溅射法在普通载波片上制备了厚度130nm左右的ITO薄膜,分别在100、200、300和400℃下退火1h。测量了退火前后几个样品的XRD和透射率,利用椭偏解谱方法对几个样品的透射谱进行建模及解谱,结果表明,未退火样品为非晶结构,退火后为多晶结构;退火温度在300℃以下的样品,随着退火温度的升高其n和k值都有明显的降低,退火温度为400℃的样品n和k值却有所增大。利用吸收系数得到了几个样品的直接带隙,其变化范围在3.7eV^3.9eV之间。 展开更多
关键词 光学常数测量 透射谱 建模及解谱 ITO薄膜
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全程恒定基座姿态零扰动的空间机械臂轨迹规划 被引量:3
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作者 黄兴宏 贾英宏 +1 位作者 徐世杰 卢山 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2017年第3期488-496,共9页
本文研究了全程恒定基座姿态零扰动的自由漂浮空间机器人(FFSR)末端位姿轨迹规划的问题。针对无运动学冗余自由度的三关节平面FFSR系统,首先建立了其末端位姿与关节角之间的状态变换关系,然后给出了以基座姿态和关节角为状态变量的系统... 本文研究了全程恒定基座姿态零扰动的自由漂浮空间机器人(FFSR)末端位姿轨迹规划的问题。针对无运动学冗余自由度的三关节平面FFSR系统,首先建立了其末端位姿与关节角之间的状态变换关系,然后给出了以基座姿态和关节角为状态变量的系统方程。根据该系统方程,利用非线性系统的可控性判据证明了在保证全程恒定基座姿态零扰动的前提下,对FFSR系统的末端位置和姿态同时作轨迹规划的可行性;再利用最优控制策略,将轨迹规划问题转换为最优控制问题,设计了一种全程恒定基座姿态零扰动的末端位姿轨迹规划方法。数值仿真验证了结论的正确性和设计方法的有效性。 展开更多
关键词 自由漂浮空间机器人(FFSR) 轨迹规划 全程恒定基座姿态零扰动 可控性 控制函数参数化
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Accurate potential energy function and spectroscopic study of the X^2Σ^+,A^2Ⅱ and B^2Σ^+ states of the CP radical 被引量:3
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作者 刘玉芳 贾毅 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第3期170-176,共7页
This paper calculates the equilibrium internuclear separations, the harmonic frequencies and the potential energy curves of the X^2∑+, A^2П and B^2∑+ states of the CP radical by the highly accurate valence intern... This paper calculates the equilibrium internuclear separations, the harmonic frequencies and the potential energy curves of the X^2∑+, A^2П and B^2∑+ states of the CP radical by the highly accurate valence internally contracted multireference configuration interaction method with correlation-consistent basis sets (aug-cc-pV6Z for C atom and aug-cc-pVQZ for P atom). The potential energy curves are all fitted with the analytic potential energy function by the least-square fitting. Employing the analytic potential energy function, we determine the spectroscopic constants (Be, αe and ωeχe) of these states. For the X2∑+ state, the obtained values of De, Be, αe, ωeχe, Re and ωe are 5.4831 eV, 0.792119 cm-1, 0.005521 cm-1, 6.89653 cm-1, 0.15683 nm, 12535.11 cm-1, respectively. For the A2H state, the present values of De, Be,αe, ωeχe, Re and We are 4.586 eV, 0.703333 cm-1, 0.005458 cm-1, 6.03398 cm-1, 0.16613 nm, 1057.89 cm-1, respectively. For the B2E+ state, the present values of De, Be, αe, ωeχe, Re and We are 3.506 eV, 0.677561 cm-1, 0.00603298 cm-1, 5.68809 cm-1, 0.1696 nm, 822.554 cm-1, respectively. For these states, the vibrational states with the rotational quantum number J equals zero (J = 0) are studied by solving the radial nuclear Schr6dinger equation using the Numerov method. For each vibrational state, the vibrational level, the classical turning points, the rotational inertial and the centrifugal distortion constants are calculated. Comparison is made with recent theoretical and experimental results. 展开更多
关键词 multi-reference configuration interaction potential energy curve molecular constant spectroscopic parameter
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二阶常系数非齐次线性微分方程一特解的积分求法 被引量:2
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作者 吴晓平 《大学数学》 1996年第2期123-126,共4页
本文给出二阶常系数非齐次线性微分方程的一个特解的积分公式.并给出证明。
关键词 常微分方程 特解 参变量积分
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ASTROPHYSICAL CONSTANTS AND PARAMETERS
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作者 K.A.Olive K.Agashe +208 位作者 C.Amsler M.Antonelli J.-F.Arguin D.M.Asner H.Baer H.R.Band R.M.Barnett T.Basaglia C.W.Bauer J.J.Beatty V.I.Belousov J.Beringer G.Bernardi S.Bethke H.Bichsel O.Biebe E.Blucher S.Blusk G.Brooijmans O.Buchmueller V.Burkert M.A.Bychkov R.N.Cahn M.Carena A.Ceccucci A.Cerr D.Chakraborty M.-C.Chen R.S.Chivukula K.Copic G.Cowan O.Dahl G.D'Ambrosio T.Damour D.de Florian A.de Gouvea T.DeGrand P.de Jong G.Dissertor B.A.Dobrescu M.Doser M.Drees H.K.Dreiner D.A.Edwards S.Eidelman J.Erler V.V.Ezhela W.Fetscher B.D.Fields B.Foster A.Freitas T.K.Gaisser H.Gallagher L.Garren H.-J.Gerber G.Gerbier T.Gershon T.Gherghetta S.Golwala M.Goodman C.Grab A.V.Gritsan C.Grojean D.E.Groom M.Grnewald A.Gurtu T.Gutsche H.E.Haber K.Hagiwara C.Hanhart S.Hashimoto Y.Hayato K.G.Hayes M.Heffner B.Heltsley J.J.Hernandez-Rey K.Hikasa A.Hocker J.Holder A.Holtkamp J.Huston J.D.Jackson K.F.Johnson T.Junk M.Kado D.Karlen U.F.Katz S.R.Klein E.Klempt R.V.Kowalewski F.Krauss M.Kreps B.Krusche Yu.V.Kuyanov Y.Kwon O.Lahav J.Laiho P.Langacker A.Liddle Z.Ligeti C.-J.Lin T.M.Liss L.Littenberg K.S.Lugovsky S.B.Lugovsky F.Maltoni T.Mannel A.V.Manohar W.J.Marciano A.D.Martin A.Masoni J.Matthews D.Milstead P.Molaro K.Monig F.Moortgat M.J.Mortonson H.Murayama K.Nakamura M.Narain P.Nason S.Navas M.Neubert P.Nevski Y.Nir L.Pape J.Parsons C.Patrignani J.A.Peacock M.Pennington S.T.Petcov Kavli IPMU A.Piepke A.Pomarol A.Quadt S.Raby J.Rademacker G.Raffel B.N.Ratcliff P.Richardson A.Ringwald S.Roesler S.Rolli A.Romaniouk L.J.Rosenberg J L.Rosner G.Rybka C.T.Sachrajda Y.Sakai G.P.Salam S.Sarkar F.Sauli O.Schneider K.Scholberg D.Scott V.Sharma S.R.Sharpe M.Silari T.Sjostrand P.Skands J.G.Smith G.F.Smoot S.Spanier H.Spieler C.Spiering A.Stahl T.Stanev S.L.Stone T.Sumiyoshi M.J.Syphers F.Takahashi M.Tanabashi J.Terning L.Tiator M.Titov N.P.Tkachenko N.A.Tornqvist D.Tovey G.Valencia G.Venanzoni M.G.Vincter P.Vogel A.Vogt S.P.Wakely W.Walkowiak C.W.Walter D.R.Ward G.Weiglein D.H.Weinberg E.J.Weinberg M.White L.R.Wiencke C.G.Wohl L.Wolfenstein J.Womersley C.L.Woody R.L.Workman A.Yamamoto W.-M.Yao G.P.Zeller O.V.Zenin J.Zhang R.-Y.Zhu F.Zimmermann P.A.Zyla G.Harper V.S.Lugovsky P.Schaffner 《Chinese Physics C》 SCIE CAS CSCD 2014年第9期110-111,共2页
Table 2.1. Revised November 2013 by D.E. Groom (LBNL). The figures in parentheses after some values give the 1-σ uncertainties in the last digit(s). Physical constants are from Ref. 1. While every effort has been... Table 2.1. Revised November 2013 by D.E. Groom (LBNL). The figures in parentheses after some values give the 1-σ uncertainties in the last digit(s). Physical constants are from Ref. 1. While every effort has been made to obtain the most accurate current values of the listed quantities, the table does not represent a critical review or adjustment of the constants, and is not intended as a primary reference. 展开更多
关键词 PLANCK CMB ASTROPHYSICAL constantS AND parameterS LENGTH
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FLRW non-singular cosmological model in general relativity
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作者 Shibesh Kumar Jas Pacif Bivudutta Mishra 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第12期2141-2150,共10页
A singularity free cosmological model is obtained in a homogeneous and isotropic background with a specific form of the Hubble parameter in the presence of an interacting dark energy represented by a time-varying cosm... A singularity free cosmological model is obtained in a homogeneous and isotropic background with a specific form of the Hubble parameter in the presence of an interacting dark energy represented by a time-varying cosmological constant in general relativity. Different cases that arose have been extensively studied for different values of the curvature parameter. Some interesting results have been found with this form of the Hubble parameter to meet the possible negative value of the decelera- tion parameter (- 1/3≤ q 〈 0) as the current observations reveal. For some particular values of these parameters, the model reduces to Berman's model. 展开更多
关键词 singularity -- cosmological constant -- dark energy -- parameter
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On the Cosmic Evolution of the Quantum Vacuum Using Two Variable G Models and Winterberg’s Thesis
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作者 Christopher Pilot 《Journal of High Energy Physics, Gravitation and Cosmology》 2023年第4期1134-1160,共27页
We work within a Winterberg framework where space, i.e., the vacuum, consists of a two component superfluid/super-solid made up of a vast assembly (sea) of positive and negative mass Planck particles, called planckion... We work within a Winterberg framework where space, i.e., the vacuum, consists of a two component superfluid/super-solid made up of a vast assembly (sea) of positive and negative mass Planck particles, called planckions. These material particles interact indirectly, and have very strong restoring forces keeping them a finite distance apart from each other within their respective species. Because of their mass compensating effect, the vacuum appears massless, charge-less, without pressure, net energy density or entropy. In addition, we consider two varying G models, where G, is Newton’s constant, and G<sup>-1</sup>, increases with an increase in cosmological time. We argue that there are at least two competing models for the quantum vacuum within such a framework. The first follows a strict extension of Winterberg’s model. This leads to nonsensible results, if G increases, going back in cosmological time, as the length scale inherent in such a model will not scale properly. The second model introduces a different length scale, which does scale properly, but keeps the mass of the Planck particle as, ± the Planck mass. Moreover we establish a connection between ordinary matter, dark matter, and dark energy, where all three mass densities within the Friedman equation must be interpreted as residual vacuum energies, which only surface, once aggregate matter has formed, at relatively low CMB temperatures. The symmetry of the vacuum will be shown to be broken, because of the different scaling laws, beginning with the formation of elementary particles. Much like waves on an ocean where positive and negative planckion mass densities effectively cancel each other out and form a zero vacuum energy density/zero vacuum pressure surface, these positive mass densities are very small perturbations (anomalies) about the mean. This greatly alleviates, i.e., minimizes the cosmological constant problem, a long standing problem associated with the vacuum. 展开更多
关键词 Winterberg Model Planck Particles Positive and Negative Mass Planck Particles Planckions Quantum Vacuum Space as a Superfluid/Supersolid Extended Models for Space Cosmological constant Higgs Field as a Composite Particle Higgs Boson Inherent Length Scale for the Vacuum Dark Energy Cosmological Scaling Behavior for the Quantum Vacuum Variable G Models Extended Gravity Newton’s constant as an Order parameter High Energy Behavior for the Vacuum
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