Results 261 to 270 of about 11,049,624 (308)

The general form of the quadrupole ion trap potential

International Journal of Mass Spectrometry and Ion Physics, 1983
R. D. Knight
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Potential distribution and focal properties of electrostatic quadrupole lenses

Journal of Physics E: Scientific Instruments, 1978
The potential distribution of a quadrupole lens with circular electrodes is calculated by successive over-relaxation techniques involving the numerical solution of Laplace's equation in three dimensions. The results show that the modified bell-shaped model (parameters: 2z0=l-1.1a; b=1.44a) is a very close approximation to the potential function for the
S Okayama, H Kawakatsu
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Nonlocal potentials and the quadrupole moment of the deuteron

Journal of Physics G: Nuclear Physics, 1976
It is demonstrated that for nonlocal potentials the quadrupole moment of the deuteron is not determined by the parameters which describe the scattering in the 3S1-3D1 state.
M W Kermode, J R Mines, M M Mustafa
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Quadrupole Oscillator Strengths of Helium Interacting with Debye Potentials

Few-Body Systems, 2012
The influence of Debye potentials on the quadrupole oscillator strengths of helium atom is investigated using highly correlated wave functions within a framework of a variational method. The quadrupole oscillator strengths for the 1,3S–1,3D, 1,3P–1,3P and 1,3D–1,3D transitions of He for various screening parameters are reported for the first time in ...
Pinghui Jiang, Sabyasachi Kar
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Electrostatic quadrupole lens simulation in potential array relaxation programs

Rapid Communications in Mass Spectrometry, 1989
Abstract Lens and ion trajectory simulation programs, such as the popular program SIMION, which employ potential array relaxation methods, are very useful in designing and modifying ion lens systems. Unfortunately, these programs cannot simulate lenses of certain geometries such as quadrupoles. Several approaches for portraying static
Palitha Jayaweera, Louis Ramaley, A. J. H. Boerboom   +2 more
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Time-orbiting-potential quadrupole magnetic trap for cold atoms

Physical Review A, 1998
An analytical theory of the time-orbiting-potential quadrupole magnetic trap for cold atoms is developed. It is shown that the rotating magnetic field used to create the time-averaged harmonic potential is responsible for the formation of quasienergy states of an atom in the trap.
Vladimir G. Minogin, James A. Richmond, Geoffrey I. Opat   +2 more
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Quadrupoles in potential flow: two model problems

Journal of Fluid Mechanics, 1982
The Ffowcs Williams-Hawkings formulation of the sources of the acoustic analogy is examined by reference to two compressible inviscid flows whose density and velocity fields are known exactly. The purpose of this exercise is to generate some feel for the importance of the various source terms in determining the sound of moving surfaces with shocks, and
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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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