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991.
The spatial structure of a luminous cloud near a hydrogen pellet sublimated in a tokamak plasma is investigated experimentally. The luminous cloud has the form of a constant-intensity plateau extended along the magnetic field and is surrounded by an exponentially fading halo. The cross size of the plateau is determined by the boundary of the ionization region of atoms leaving the pellet surface. The plateau length is approximately determined by the balance between the pressures in the luminous cloud and the bulk plasma. Taking into account the structure described is important for the correct interpretation of the signals from alpha-particle diagnostics by charge-exchange neutral fluxes, because these signals depend on the characteristic dimensions of the cloud. 相似文献
992.
Golovchenko A. V. Pil'o S. G. Brovarets V. S. Drach B. S. 《Russian Journal of General Chemistry》2003,73(11):1832-1833
Russian Journal of General Chemistry - 相似文献
993.
B. Bidgaray 《Numerical Methods for Partial Differential Equations》2003,19(3):284-300
In this article we derive new time discretizations for the numerical simulation of Maxwell‐Bloch equations. These discretizations decouple the equations, thus leading to improved efficiency. This approach may be combined with the fulfilment of physical properties, such as positiveness properties, which are not accounted for by classical schemes. Our time discretizations are moreover proved to be nonlinearly stable. © 2003 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 19: 284–300, 2003. 相似文献
994.
D. Barrios Rolanía G. Lpez Lagomasino E. B. Saff 《Journal of Approximation Theory》2003,124(2):263-281
Using a convergence theorem for Fourier–Padé approximants constructed from orthogonal polynomials on the unit circle, we prove an analogue of Hadamard's theorem for determining the radius of m-meromorphy of a function analytic on the unit disk and apply this to the location of poles of the reciprocal of Szeg
functions. 相似文献
995.
D. V. Makarov A. T. Belyaevskii Yu. P. Men’shikov D. P. Nesterov M. F. Yusupova 《Russian Journal of Applied Chemistry》2007,80(2):175-180
Behavior of a skeleton silicate, nepheline, in the reaction of fluorination with ammonium hydrofluoride was studied by means of differential-thermal, X-ray phase, and chemical analyses, IR spectroscopy, and scanning electron microscopy. 相似文献
996.
Alan L. Andrew 《BIT Numerical Mathematics》2003,43(3):485-503
The asymptotic correction technique of Paine, de Hoog and Anderssen can dramatically improve the accuracy of finite difference or finite element eigenvalues at negligible extra cost if closed form expressions are available for the errors in a simpler related problem. This paper gives closed form expressions for the errors in the eigenvalues of certain Sturm–Liouville problems obtained by various methods, thereby increasing the range of problems for which asymptotic correction can achieve maximum efficiency. It also investigates implementation of the method for more general problems. 相似文献
997.
998.
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1000.
A hybrid finite-element method, combining ideas from a modified method of characteristics and the streamline diffusion method, delivers accurate solutions to the advection–diffusion equation. An error analysis for the case of tensorial diffusion shows that the lowest-order version of the scheme, which allows one to use a symmetric linear solvers at each time step, possesses first-order accuracy in time and space. Numerical experiments demonstrate the scheme's ability to model advection-dominated transport of solute plumes without distorting sharp fronts. © 1995 John Wiley & Sons, Inc. 相似文献