MEASUREMENT METHODS OF ATOMIC AND MOLECULAR TRANSITION PROBABILITIES AT FACULTE DES SCIENCES DE BREST

Author(s):  
Andrée Johannin-Gilles
1967 ◽  
Vol 45 (5) ◽  
pp. 1715-1727 ◽  
Author(s):  
P. G. Wilkinson

The spectral intensity, Iem, of the microwave excited continuous emission in molecular argon has been investigated from 1 060 to 1 450 Å as a function of pressure (pAr) with the result:[Formula: see text]The Ar2 continuum, like Xe2, Kr2, and Ne2 (X2), exhibits a sharp short wavelength limit corresponding energetically to the 3p54s3P0 resonance configuration and two intensity maxima at 1 080 and 1 265 Å. The integrated intensities of the rare-gas continua compare as follows:[Formula: see text]with (Iem)Ne expected to be weaker still. The pressure dependence and the short wavelength limit suggest a two-body collision process involving 3P0 atoms as the controlling step to produce [Formula: see text] molecules responsible for the continuum.Although the lifetimes of the 3P0 atoms do play a kinetic role in the continuum production, it is concluded that the molecular transition probabilities, [Formula: see text] predominate and decrease, as expected in the direction Xe2* to Ne2* in the approach (weaker spin-orbit coupling) to Hund's case b.


Author(s):  
C. C. Ahn ◽  
D. H. Pearson ◽  
P. Rez ◽  
B. Fultz

Previous experimental measurements of the total white line intensities from L2,3 energy loss spectra of 3d transition metals reported a linear dependence of the white line intensity on 3d occupancy. These results are inconsistent, however, with behavior inferred from relativistic one electron Dirac-Fock calculations, which show an initial increase followed by a decrease of total white line intensity across the 3d series. This inconsistency with experimental data is especially puzzling in light of work by Thole, et al., which successfully calculates x-ray absorption spectra of the lanthanide M4,5 white lines by employing a less rigorous Hartree-Fock calculation with relativistic corrections based on the work of Cowan. When restricted to transitions allowed by dipole selection rules, the calculated spectra of the lanthanide M4,5 white lines show a decreasing intensity as a function of Z that was consistent with the available experimental data.Here we report the results of Dirac-Fock calculations of the L2,3 white lines of the 3d and 4d elements, and compare the results to the experimental work of Pearson et al. In a previous study, similar calculations helped to account for the non-statistical behavior of L3/L2 ratios of the 3d metals. We assumed that all metals had a single 4s electron. Because these calculations provide absolute transition probabilities, to compare the calculated white line intensities to the experimental data, we normalized the calculated intensities to the intensity of the continuum above the L3 edges. The continuum intensity was obtained by Hartree-Slater calculations, and the normalization factor for the white line intensities was the integrated intensity in an energy window of fixed width and position above the L3 edge of each element.


2018 ◽  
Vol 11 (4) ◽  
pp. 249-266 ◽  
Author(s):  
Judith Znanewitz ◽  
Lisa Braun ◽  
David Hensel ◽  
Claudia Fantapié Altobelli ◽  
Fabian Hattke

1993 ◽  
Vol 13 (02) ◽  
pp. 96-105 ◽  
Author(s):  
H. Beeser ◽  
U. Becker ◽  
H. J. Kolde ◽  
E. Spanuth ◽  
P. Witt ◽  
...  

SummaryThe prothrombin time (PT), obtained from a fresh normal plasma pool (FPP), is the basis both for the establishment of the 100% activity (normal plasma) and for the ratio calculation used in the International Normalized Ratio (INR) according to the recommendations of the ICSH/ICTH (6). Today the PT of lyophilized normal plasma pools are successfully used as reference for the assessment of samples in proficiency studies. However, a lack of comparability is to be recognized. Therefore the Committee of Hematology of the German Association of Diagnostics’ and Diagnostic Instruments’ Manufacturers (VDGH) decided to produce a candidate reference plasma (VDGH Reference Plasma) which was calibrated against fresh normal plasma pools in an international study.The basic calibration was performed by using the same certified BCR thromboplastin (BCT/099) by all participants. The endpoint was determined manually and by using the coagulometer Schnitger-Gross. In additional testings each participant used his own routine thromboplastins and methods. Calculating the ratio [PT VDGH Reference Plasma (sec)/PT fresh normal plasma pool (sec)] the VDGH Reference Plasma showed a deviation from the average fresh normal plasma pool of 1.05 both with the BCT/099 and with all thromboplastins. There were obtained some statistical differences between “plain” and “combined’’ (added factor V and fibrinogen) thromboplastins. No statistical difference was found between the different endpoint measurement methods (manual, mechanical, optical).In spite of these statistical deviations the VDGH Reference Plasma can be used for the standardization of the PT-normal (100%) value with different ratios for plain (1.06) and combined (1.02) thromboplastins. The manufacturers will use this VDGH Reference Plasma for the calibration of their commercially available calibration plasmas, which allows the user of such a material to calculate a calibrated 100% PT value.


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