Results 151 to 160 of about 223,941 (197)

Quadrupole perturbation of the harmonic oscillator potential

Zeitschrift f�r Physik A: Atoms and Nuclei, 1977
TheSU(3) symmetry of the harmonic oscillator potential is used to calculate exactly the second order energy correction, caused by quadrupole deformations. This can be done in a purely algebraic manner, using the Dalgarno-Schwartz formulation of perturbation theory. Some connections of this method with group theory are discussed and an extension to more
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Potential Distribution and Transmission Characteristics in a Curved Quadrupole Ion Guide

Journal of the American Society for Mass Spectrometry, 2011
The potential distribution in the curved quadrupole is exactly characterized by the Laplace equation, and an approximate solution to the Laplace equation is calculated. We represent the Laplace equation under the coordinates named minimal rotation frame (MRF) and derive an expression on the hexapole and octopole superposition.
Xiaoyu, Zhou, Caiqiao, Xiong, Gaoping, Xu, Hao, Liu, Yin, Tang, Zhiqiang, Zhu, Rui, Chen, Haoxue, Qiao, Yao-Hsin, Tseng, Wen-Ping, Peng, Zongxiu, Nie, Yi, Chen   +11 more
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Study of Quadrupole Mass Filter Supplied with a New Impulsional Potential

European Journal of Mass Spectrometry, 2012
The paper reports on some theoretical studies concerning the impulsional mode of a quadrupole mass filter (QMF) supplied with a new periodic impulsional radio frequency voltage of the form Vaccos(ω t)⌊1 + kcos(⅓ω t)⌋/1 – √ kcos(2ω t) with 0 ≤ k < 1 (⌊.⌋ means floor function) and eventually compares it to the classical sinusoidal case, k = 0.
Sarkosh Seddighi, Chaharborj, Seyyed M, Sadat Kiai, Ismail, Fudziah, Zanariah A, Majid   +3 more
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Far-field potential production by quadrupole generators in cylindrical volume conductors

Electroencephalography and Clinical Neurophysiology/Evoked Potentials Section, 1993
Far-field potentials have been observed clinically and recognized as such for approximately 30 years. Unfortunately a complete understanding of far-field potential generation is not yet at hand. An attractive model is the representation of an action potential by a quadrupole consisting of a leading and trailing dipole with respect to the direction of ...
D, Dumitru, J C, King
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Phonon-induced quadrupole potential in diamond-type semiconductors

Journal of Physics C: Solid State Physics, 1972
Two models of covalent crystals, the shell model and the bond charge model, are used to calculate the quadrupole component of the valence charge distortion brought about by displacement of an atom from its equilibrium position. On the basis of the shell model it appears that the sources of the quadrupole extend over a considerable region around the ...
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Nuclear quadrupole moment and effects of nucleus–nucleus scattering potential

Modern Physics Letters A, 2019
This paper presents the results of the nuclear electrical quadrupole moment of the 17O and 2H before and after their scattering interaction near the Coulomb barrier. The distribution of nuclei’s charge (the quadrupole moment of nuclei) was examined for 2H and 17O when interacting together.
Laleh Nickhah, Ali Akbar Rajabi, Majid Hamzavi   +2 more
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Gauge potential for neutral atoms in a magnetic quadrupole field

Journal of the Korean Physical Society, 2013
We consider a spinor Bose-Einstein condensate of neutral atoms in a magnetic quadrupole field and investigate the gauge potential derived from the spatially-varying magnetic field. We discuss the critical condition for a singular, quantized vortex state being energetically favored in the spinor condensate and find that it is necessary under ...
Yong-il Shin, Jae-yoon Choi
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Nonadiabatic transport of cold atoms in a magnetic quadrupole potential

Applied Physics Letters, 2010
We experimentally demonstrated the transport of cold atoms in a magnetic quadrupole trap in the nonadiabatic regime on the order of the trap period. The trap potential velocity was controlled by varying the currents of the two pairs of anti-Helmholtz coils. We efficiently transported cold atoms with two velocity regimes.
Dongyuan Chen, Haichao Zhang, Xinping Xu, Tang Li, Yuzhu Wang   +4 more
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Quadrupole Correction: From Molecular Electrostatic Potential to Free Energies of Halogen Bonding

Journal of Chemical Theory and Computation, 2018
Recently several molecular mechanics models of halogen bonding have been published. They describe the electrostatic potential anisotropy near the heavy halogen atom (known as a σ-hole) in different ways, ranging from an all-atom multipole expansion to a single positive extra-point charge.
Oleg I. Titov, Dmitry A. Shulga, Vladimir A. Palyulin   +2 more
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Navigation and collision avoidance for nonholonomic robots using quadrupole potential function

2017 2nd International Conference on Advanced Robotics and Mechatronics (ICARM), 2017
In this paper, for path planning in indoor cluttered environments, a non-holonomic motion planner based on a novel artificial potential field is presented. Combined with a low-level controller, it not only guarantees obstacle avoidance but also can stabilize the noholonomic mobile robot to a goal configuration including orientation.
Wang Yuan, Zhijun Li
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