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Scaling of residual displacements in terms of elastic and inelastic spectral displacements for existing SDOF systems

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Earthquake Engineering and Engineering Vibration 2020年第1期19卷 71-85页

作者： m.g.Harikrishnan Vinay K.gupta Department of Civil Engineering Indian Institute of Technology Kanpur

Structures undergoing inelastic displacements during earthquake ground motions are known to sustain some amount of residual displacements, which may make them unusable or unsafe. In this study an attempt is made to estimate residual displacements for elastic-perfectly-plastic single-degree-of-freedom oscillators with a given lateral strength ratio. It is observed in the case of a class of ground motions that there are no trends in the dependence of residual displacement on the temporal features of the ground motion, and thus any estimation of residual displacements should be carried out only in the statistical sense. Statistical estimation of residual displacement spectrum via normalization with respect to inelastic or elastic spectral displacements is considered, and it is found that normalization with respect to inelastic spectral displacements is preferable. Expressions for residual displacement spectra are proposed for both types of normalizations and for the givenlateral-strength-ratio type oscillators.

关键词： residual displacement spectrum lateral strength ratio elastic-perfectly-plastic oscillator inelastic displacement spectrum elastic displacement spectrum horizontal ground motions

Hartree-Fock-Roothaan Calculations for ground States of Some Atoms Using minimal Basis Sets of Integer and Noninteger n-STOs

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Chinese Journal of Chemistry 2004年第11期22卷 1262-1266页

作者： gümü■ Sedat ZSO■AN Telhat Department of Physics Amasya Education Faculty Ondokuz Mayis University 05189 Amasya TURKEYDepartment of Physics Amasya Education Faculty Ondokuz Mayis University 05189 Amasya TURKEY

Hartree-Fock-Roothaan (HFR) calculations for ground states of some atoms, i.e. He, Be, Ne, Ar, and Kr have been performed using minimal basis sets of Slater type orbitals (STOs) with integer and noninteger principal quan-tum numbers (integer n-STOs and noninteger n-STOs). The obtained total energies for these atoms using minimal basis sets of integer n-STOs are in good agreement with those in the previous literature. On the other hand, for the case of minimal basis sets of noninteger n-STOs, although the calculated total energies of these atoms agree well with the results in literature, some striking results have been obtained for atoms Ar and Kr. Our computational re-sults for the energies of atoms Ar and Kr are slightly better than those in literature, by amount of 0.00222 and 0.000054 a.u., respectively. The improvement in the energies of atoms Ar and Kr may result from the efficient cal-culations of one-center two-electron integrals over noninteger n-STOs. For some atomic ions in their ground state, HFR calculations have been carried out using minimal basis sets of noninteger n-STOs. The obtained total energies for these atomic ions are substantially lower than those available in literature.

关键词： Hartree-Fock-Roothaan Slater type orbital

DISSOLUTION KINETICS OF PHOSPHATE ORE IN ACIDIC SOLUTIONS

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Chinese Journal of Chemical Engineering 1994年第2期2卷 13-22页

作者：马三剑 E.T.m.J.martynowicz g.J.Witkamp g.m.vanRosmalen Faculty of Chemical Technology and material Science Delft University of TechnologyLeeghwaterstraat 442628RZ DelftThe Netherlands

The dissolution kinetics of Florida and Jordan phosphate ore was studied in diluted nitric acid (0.2, 0.5, 1.0 mol ·L-1), and in phosphoric acid (55 wt% H3PO4) aqueous solutions. It was found that the hydrogen ions concentration is a controlling factor, but the calcium ions concentration can not affect the dissolution rate in the range of 0.0 and 2.0 wt% Ca2+. The effects of temperature, stirring intensity and the size of ore particles were also investigated. The transfer of hydrogen ion depends on the diffusion, while the calcium ions transfer is assumed to be depended on mechanically stripping. The shrinking core model with hydrogen ions diffusion control match the experimental results.

关键词： dissolution kinetics phosphate ore diffusion mechanically stripping hydrogen calcium ions concentration shrinking core model

melting phenomenon in magneto hydro-dynamics steady flow and heat transfer over a moving surface in the presence of thermal radiation

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Chinese Physics B 2013年第3期22卷 57-62页

作者： Reda g.Abdel-Rahman m.m.Khader Ahmed m.megahed Department of mathematics Faculty of ScienceBenha University

The Lie group method is applied to present an analysis of the magneto hydro-dynamics（mHD） steady laminar flow and the heat transfer from a warm laminar liquid flow to a melting moving surface in the presence of thermal *** using the Lie group method,we have presented the transformation groups for the problem apart from the scaling *** application of this method reduces the partial differential equations（PDEs） with their boundary conditions governing the flow and heat transfer to a system of nonlinear ordinary differential equations（ODEs） with appropriate boundary *** resulting nonlinear system of ODEs is solved numerically using the implicit finite difference method（FDm）.The local skin-friction coefficients and the local Nusselt numbers for different physical parameters are presented in a table.

关键词： Lie group method magneto hydro-dynamics melting phenomenon Newtonian fluid radiation

Quantum phase distribution and the number-phase Wigner function of the generalized squeezed vacuum states associated with solvable quantum systems

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Chinese Physics B 2012年第5期21卷 265-273页

作者： g.R.Honarasa m.K.Tavassoly m.Hatami Department of Physics Faculty of ScienceShiraz University of Technology Atomic and molecular group Faculty of PhysicsYazd University

The quantum phase properties of the generalized squeezed vacuum states associated with solvable quantum systems are studied by using the Pegg-Barnett ***,two nonclassical features,i.e.,squeezing in the number and phase operators,as well as the number-phase Wigner function of the generalized squeezed states are *** to some actual physical situations,the present approach is applied to two classes of generalized squeezed states：solvable quantum systems with discrete spectra and nonlinear squeezed states with particular nonlinear ***,the time evolution of the nonclassical properties of the considered systems has been numerically investigated.

关键词： squeezed vacuum states solvable quantum systems phase distribution number phaseWigner function

Effect of Impeller geometry and Tongue Shape on the Flow Field of Cross Flow Fans

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Journal of Thermal Science 2003年第2期12卷 118-125页

作者： m.govardhan g.Venkateswarlu Department of mechanical Engineering Indian Institute of Technology MadrasChennai 600 036IndiaDepartment of Mechanical EngineeringIndian Institute of Technology MadrasChennai 600 036India

Experiments were conducted to investigate the effect of impeller geometry and tongue shape on the flow field of cross flow *** impellers(Ⅰ，Ⅱ，Ⅲ）having same outer diameter,but different radius ratio and blade angles were employed for the *** impeller was tested with two tongue *** survey was carried out for each impeller and tongue shape at two flow *** for each flow coefficient at different circumferential *** flow is two-dimensional along the blade span except near the *** total pressure developed by the impellers in each case is found to be maximum at a circumferential position of around 270°.The total and static pressures at the inlet of impellers are more or less same regardless of impeller and tongue geometry,but they vary considerably at exit of the *** Ⅲ with tongue T2 develops higher total pressure and efficiency where as impeller Ⅱ with tongue T2 develops minimum total *** diffusion and smaller vortex size are the reasons for better performance of impeller Ⅲwith tongue T2。

关键词： Impeller tongue circumferential position flow coefficient eccentric vortex total pressure coefficient static pressure coefficient.

Assessment of mercury(II) bioavailability using a bioluminescent bacterial biosensor: Practical and theoretical challenges

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Journal of Environmental Sciences 2010年第8期22卷 1137-1143页

作者： Paulo R g Barrocas William m Landing Robert J m Hudson Department of Sanitation and Environmental Health National School of Public Health Oswaldo Cruz Foundation Department of Oceanography Florida State University. Tallahassee Department of Natural Resources and Environmental Sciences University of Illinois

Critical methodological challenges in the microbial biosensor approach to assessing Hg（II） bioavailability were evaluated from the perspective of analytical chemists. The main challenge stems from the fact that the chemical speciation of Hg（II） in natural waters exerts a major control on its bioavailability, yet its natural complexation equilibria are extensively altered during conventional bioassays. New data, obtained using a bioluminescent Hg（II）-biosensor, that illustrate these challenges are presented and potential solutions proposed.

关键词： mercury bioavailability biosensor chemical speciation bioluminescent

The Relationship Between Developmental Accumulation of Leaf Soluble Proteins and Vernalization Response of Wheat(Triticum aestivum ***. Thell)

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Agricultural Sciences in China 2009年第4期8卷 410-417页

作者： m majdi g Karimzadeh S mahfoozi Plant Breeding and Biotechnology Department Faculty of AgricultureTarbiat Modares UniversityP.O.Box 14115-336Tehran ***Iran Physiology-Agronomy Unit of Department of Cereals Research Seed and Plant Improvement InstituteKaraj 315854119Iran

The relationship between vernalization requirement and quantitative and qualitative changes in total leaf soluble proteins were determined in one spring （cv. Kohdasht） and two winter （cvs. Sardari and Norstar） cultivars of wheat （Triticum aestivum L.） exposed to 4℃. Plants were sampled on days 2, 14, 21 and 35 of exposure to 4℃. The final leaf number （FLN） was determined throughout the vernalization periods （0, 7, 14, 24, and 35 d） at 4℃. The final leaf number decreased until days 24 and 35 in Sardari and Norstar eultivars, respectively, indicating the vernalization saturation at these times. No clear changes were detected in the final leaf number of Kohdash cultivar, verifying no vernalization requirement for this spring wheat cultivar. Comparing with control, clear cold-induced 2-fold increases in proteins quantity occurred after 48 h following the 4℃-treatment in the leaves of the both winter wheat cultivars but, such response was not detected in the spring cultivar. However, the electrophoretic protein patterns showed between-cultivar and between-temperature treatment differences. With increasing exposure time to 4℃, the winter cultivars tended to produce more HmW polypeptides than the spring cultivar. Similar proteins were induced in both Sardari and Norstar winter wheat cultivars, however, the long vernalization requirement in Norstar resulted in high level and longer duration of expression of cold-induced proteins compared to Sardari with a short vernalization requirement. These observations indicate that vernalization response regulates the expression of low temperature （LT） tolerance proteins and determines the duration of expression of LT- induced proteins.

关键词： soluble proteins wheat Triticum aestivum L. final leaf number vernalization cold

NUmERICAL SOLUTION OF THE SINgULARLY PERTURBED PROBLEm WITH NONLOCAL BOUNDARY CONDITION

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Applied mathematics and mechanics(English Edition) 2002年第7期23卷 755-764页

作者： g.m.Amiraliyev musa CakDr Department of mathematics Y Y University65080 VanTurkey Communicated by HE Ji-huan Original Member of Editorial CommitteeAMM

Singularly perturbed boundary value problem with nonlocal conditions is examined. The appopriate solution exhibits boundary layer behavior for small positive values of the perturbative parameter. An exponentially fitted finite difference scheme on a non-equidistant mesh is constructed for solving this problem. The uniform convergence analysis in small parameter is given. Numerical example is provided, too.

关键词： exponentially fitted difference scheme singular perturbation nonlocal boundary condition