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101.
Periodic orbits belonging to the stromgren families A, B and C around the collinear libration points in the restricted three body problem have been studied when the smaller primary is a triaxial rigid body and more massive body is a source of radiation pressure. These families are determined in three different cases: (i) classical case, (ii) when bigger primary is a source of radiation pressure, (iii) when smaller primary is a triaxial rigid body and bigger primary is a source of radiation pressure. The Liapunov stability of each periodic solution has also been examined. 相似文献
102.
Plasmon dispersion in Al is estimated using the expression for the dynamic structure function,S
pl(K,ω), corresponding to the plasmon excitations in a many-electron system derived earlier. An evaluation of its plasmon linewidth
is also presented. It is observed that for Al both the dispersion and linewidth agree fairly well with experiments. 相似文献
103.
限制边连通度是对传统边连通度的推广 ,而且是计算机互连网络容错性的一个重要度量 .本文考虑两类重要的网络模型———Kautz有向图K(d ,n)和Kautz无向图UK(d ,n)的限制边连通度λ′,并得到如下结果 :除了λ′(K( 2 ,1) )不存在外 ,均有λ′(K(d ,n) ) =2d-2 ;当d≥ 3 ,n≥ 3时 ,4d-5≤λ′(UK(d ,n) ) ≤ 4d -4 . 相似文献
104.
ZHOU Li-Juan PING Rong-Gang MA Wei-Xing 《理论物理通讯》2004,42(12)
Based on Dyson-Schwinger equations (DSEs) in “rainbow“ approximation, the dynamically running mass of light quark and QCD vacuum condensate are investigated. The structure of non-local quark vacuum condensate, the values of local vacuum condensate of quarks and quark-gluon mixture, and dynamical transition of quark mass from current quark to constituent quark are illustrated. At the same time, according to the knowledge and experience learned from an extensive study of the solutions of DSEs, a parameterized form of confining quark propagator is suggested for a practical use. The new parameterized form of quark propagator is analytic everywhere in the finite complex p2-plane and has no Lehmann representation. The predictions for p2-dependence of effective quark masses, Mf(p2), defined by the self-energy functions Af(p2) and Bf(p2), both from the numerical solutions of DSEs and from its parameterized form, are shown dynamically. Our conclusion is that all numerical results are consistent with empirical values used in QCD sum rules and lattice QCD calculations. For a qualitative study, the parameterized form is a sufficiently good approximation to confining quark propagator. 相似文献
105.
A. Famulari E. Gianinetti M. Raimondi M. Sironi I. Vandoni 《Theoretical chemistry accounts》1998,99(6):358-365
The self-consistent field (SCF) for molecularinteractions algorithm, particularly devised to compute intermolecular interactions,
is extended to the case in which one of the two interacting fragments is an open shell system. The method excludes the basis
set superposition error in an a priori fashion. To preserve the simplicity of the standard SCF procedure, Guest and Saunders
equations concerning the open shell fragment are modified at the cost of a negligible complication with respect to the usual
algorithm.
Received: 27 May 1997 / Accepted: 29 May 1998 / Published online: 18 September 1998 相似文献
106.
Quantification of the velocity acceleration factor for colloidal transport in porous media using NMR
Sarah A. Creber Thomas R.R. Pintelon Michael L. Johns 《Journal of colloid and interface science》2009,339(1):168-174
Nuclear magnetic resonance (NMR) techniques were used to quantify the transport of colloids through porous media. This was achieved via the application of chemically-resolved pulsed field gradient (PFG) methods, hence probing the displacement (probability distribution) propagators of both the colloidal and continuous liquid phase. A dilute decane-in-water emulsion was used with flow through a random glass sphere packing being considered. The acquired propagators allowed for quantification of both colloidal entrapment and the velocities of both the continuous phase and the flowing colloids. The flowing colloids were found to experience a velocity acceleration factor (VAF) increase of 1.08 relative to the continuous phase. This was found to be independent of displacement observation time or flowrate. It was speculated to be a consequence of radial exclusion due to the finite size of the colloids. Simulations of the colloidal transport were also performed using a lattice Boltzmann platform and a Lagrangian particle-tracking algorithm which incorporated colloidal radial exclusion. Reasonable agreement was observed between the simulation and the experimental data. 相似文献
107.
The present work demonstrates the successful application of automated biocompatible in-tube solid-phase microextraction coupled with liquid chromatography (in-tube SPME/LC) for determination of interferon alpha(2a) (IFN α(2a)) in plasma samples for therapeutic drug monitoring. A restricted access material (RAM, protein-coated silica) was employed for preparation of a lab-made biocompatible in-tube SPME capillary that enables the direct injection of biological fluids as well as the simultaneous exclusion of macromolecules by chemical diffusion barrier and drug pre-concentration. The in-tube SPME variables, such as sample volume, draw/eject volume, number of draw-eject cycles, and desorption mode were optimized, to improve the sensitivity of the proposed method. The IFN α(2a) analyses in plasma sample were carried out within 25min (sample preparation and LC analyses). The response of the proposed method was linear over a dynamic range, from 0.06 to 3.0MIUmL(-1), with correlation coefficient equal to 0.998. The interday precision of the method presented coefficient of variation lower than 8%. The proposed automated method has adequate analytical sensitivity and selectivity for determination of IFN α(2a) in plasma samples for therapeutic drug monitoring. 相似文献
108.
采用浸渍热解法制备磁性凹凸棒土(MATP), 以磺胺二甲氧嘧啶(SDM)为模板分子, 4-乙烯基吡啶(4-VP)为功能单体, 采用反相原子转移自由基聚合(RATRP)法在MATP表面包覆印迹聚合物薄膜, 得到磁性分子印迹聚合物(MATP-MIPs), 最后在MATP-MIPs表面接枝亲水性单体甲基丙烯酸羟乙酯(HEMA), 得到新型磁性限进分子印迹复合材料(MATP-RAM-MIPs). 采用傅里叶变换红外光谱(FTIR)仪、 扫描电子显微镜(SEM)、 热重分析(TGA)仪、 振动样品磁强计(VSM)和X射线衍射(XRD)仪对材料进行了表征. 通过静态水接触角和考马斯亮蓝G-250方法证明材料外表面具有良好的亲水性和排阻蛋白的特性; 采用静态和选择性吸附实验证实MATP-RAM-MIPs对SDM具有良好的吸附选择性和较高的吸附容量. 将该材料直接用于牛血清中磺胺类药物的富集分离, 加标回收率为86.2%~100.6%, 相对标准偏差为2.1%~4.2%, 可见该材料在复杂样品前处理中具有良好的实际应用价值. 相似文献
109.
Henry Nicole González-Ramírez Roberto Flores-Moreno 《International journal of quantum chemistry》2020,120(7):e26140
Generalized one-particle propagator calculations were performed for fermions in atoms: neutrons, protons, and electrons. For this purpose, multicomponent Hartree-Fock equations were implemented using Gaussian basis sets where, for nucleons, we consider a non-Coulombic interaction, through a two-term Yukawa scalar potential and the interaction between electrons and the electrons with positive charge (protons) through a Coulombic potential. The strategy for evaluating the required interaction integrals follows Obara-Saika and Head-Gordon recurrence relations combined with the generalized Boys function suggested by Ten-no. Calculations on the isotopes 2H, 3H, 3He, 4He, 6Li, 6Be, 7Li, and 8Be were realized to test the accuracy of Koopmans' approximation and a second-order generalized one-particle propagator. Yukawa potentials were parametrized to reproduce nuclear properties as kinetic energies and radial distributions of density. These potentials produced the reference nuclear Hartree-Fock calculations on which fully ab initio propagator calculations were performed for these non-Coulombic potentials. This allowed us to explore the electronic structure of isotopes in an extended nucleus context. 相似文献
110.