Determination of Total Absorption of Na3S → nP Transitions for 5 ≦ n ≦ 28

1978 ◽  
Vol 33 (4) ◽  
pp. 432-438
Author(s):  
L. Dressler ◽  
W. Behmenburg ◽  
J. Uhlenbusch

Total absorption measurements of Na3S → nP transitions up to a main quantum number n = 28 have been performed at Na number densities in the range ≈ 1016 - 1017 cm-3 and temperatures ≈ 700-800 K. A heat pipe oven has been applied as an absorption tube in a single beam optical arrangement; experiment and data acquisition have been controlled by a computer. The results are compared with calculations using special assumptions with respect to line broadening mechanisms. The effect of binary and three-body collisions on total absorption is studied in detail. Within the pressure and main quantum number range investigated here a transition between the two types of interaction was demonstrated.

1997 ◽  
Vol 30 (4) ◽  
pp. 427-430 ◽  
Author(s):  
F. Sánchez-Bajo ◽  
F. L. Cumbrera

A modified application of the variance method, using the pseudo-Voigt function as a good approximation to the X-ray diffraction profiles, is proposed in order to obtain microstructural quantities such as the mean crystallite size and root-mean-square (r.m.s.) strain. Whereas the variance method in its original form is applicable only to well separated reflections, this technique can be employed in the cases where there is line-profile overlap. Determination of the mean crystallite size and r.m.s. strain for several crystallographic directions in a nanocrystalline cubic sample of 9-YSZ (yttria-stabilized zirconia) has been performed by means of this procedure.


2014 ◽  
Vol 16 (45) ◽  
pp. 25101-25110 ◽  
Author(s):  
Vinay Sharma ◽  
Fabian Böhm ◽  
Gerhard Schwaab ◽  
Martina Havenith

Concentration dependent THz/FIR absorption measurements allow determination of individual solvated ion resonances and their influence on the hydration water spectrum.


2013 ◽  
Vol 40 (1) ◽  
pp. 135-146
Author(s):  
Aleksandar Tomic

Newton's formula for gravity force gives greather force intensity for atraction of the Moon by the Sun than atraction by the Earth. However, central body in lunar (primary) orbit is the Earth. So appeared paradox which were ignored from competent specialist, because the most important problem, determination of lunar orbit, was inmediately solved sufficiently by mathematical ingeniosity - introducing the Sun as dominant body in the three body system by Delaunay, 1860. On this way the lunar orbit paradox were not canceled. Vujicic made a owerview of principles of mechanics in year 1998, in critical consideration. As an example for application of corrected procedure he was obtained gravity law in some different form, which gave possibility to cancel paradox of lunar orbit. The formula of Vujicic, with our small adaptation, content two type of acceleration - related to inertial mass and related to gravity mass. So appears carried information on the origin of the Moon, and paradox cancels.


2008 ◽  
Vol 5 (3) ◽  
pp. 446-448
Author(s):  
Baghdad Science Journal

A calculation have been carried out for determination some of the spectroscopic properties of Hydrogen Iodide HI molecules such as, the intensity of the absorption spectrum as a function of the variation of the temperature ranging from 10 to 1000 K. This study shows that the populations and hence intensity of the molecule increased as the temperature increased. Another determination of the maximum rotational quantum number Jmax of N2 , CO , BrF AgCl and HI molecules has been carried out.


2008 ◽  
Vol 113 (A4) ◽  
pp. n/a-n/a ◽  
Author(s):  
Dušan A. Pejaković ◽  
Konstantinos S. Kalogerakis ◽  
Richard A. Copeland ◽  
David L. Huestis

The evaluation procedures of X-ray line profiles are overviewed in this chapter. These methods can be classified into four groups, namely (1) the most simple methods that evaluate only the breadths of diffraction peaks, (2) procedures using the Fourier-transforms of line profiles for the determination of the parameters of microstructures, (3) variance methods evaluating the restricted moments of peaks, and (4) procedures fitting the whole diffraction pattern. The crystallite size distribution and the densities of lattice defects cannot be determined from the peak width alone as the rule of summation of breadths of size, strain, and instrumental profiles depends on their shape. However, the breadth methods can be used for a qualitative assessment of the main origins of line broadening (size, dislocations, planar faults) (e.g. for checking the model of microstructure used in whole powder pattern fitting procedures). The application of Fourier and variance methods is limited if the diffraction peaks are overlapping. In the case of pattern fitting procedures, usually a microstructure model is needed for the calculation of the theoretical fitting functions. The reliability of these methods increases with increasing the number of fitted peaks.


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