A polarisation-correlation analysis of the 31D state of helium excited by electron impact

1987 ◽  
Vol 20 (24) ◽  
pp. 6617-6630 ◽  
Author(s):  
J P M Beijers ◽  
S J Doornenbal ◽  
J van Eck ◽  
H G M Heideman
Keyword(s):  
Correlation Analysis ◽  
Electron Impact

Microdensitometer—computer correlation analysis of ultrastructural periodicity

1978 ◽  
Vol 36 (2) ◽  
pp. 32-33
Author(s):  
D.R. Ensor ◽  
C.G. Jensen ◽  
J.A. Fillery ◽  
R.J.K. Baker
Keyword(s):  
Correlation Analysis ◽  
Background Noise ◽  
Computer Control ◽  
Optical Diffraction ◽  
Screw Thread ◽  
Straight Line ◽  
Computer Storage ◽  
Correlation Process ◽  
Electron Microscope Image ◽  
Fixed Beam

Because periodicity is a major indicator of structural organisation numerous methods have been devised to demonstrate periodicity masked by background “noise” in the electron microscope image (e.g. photographic image reinforcement, Markham et al, 1964; optical diffraction techniques, Horne, 1977; McIntosh,1974). Computer correlation analysis of a densitometer tracing provides another means of minimising "noise". The correlation process uncovers periodic information by cancelling random elements. The technique is easily executed, the results are readily interpreted and the computer removes tedium, lends accuracy and assists in impartiality.A scanning densitometer was adapted to allow computer control of the scan and to give direct computer storage of the data. A photographic transparency of the image to be scanned is mounted on a stage coupled directly to an accurate screw thread driven by a stepping motor. The stage is moved so that the fixed beam of the densitometer (which is directed normal to the transparency) traces a straight line along the structure of interest in the image.

The measurement of inner-shell ionization cross aections by electron impact in a TEM

1992 ◽  
Vol 50 (2) ◽  
pp. 1266-1267
Author(s):  
Raynald Gauvin ◽  
Gilles L'Espérance
Keyword(s):  
Electron Impact ◽  
Cross Sections ◽  
Weight Fraction ◽  
Thin Foil ◽  
Specimen Thickness ◽  
Ionization Cross ◽  
Electron Dose ◽  
Total Electron ◽  
Inner Shell Ionization ◽  
Shell Ionization

Values of cross sections for ionization of inner-shell electrons by electron impact are required for electron probe microanalysis, Auger-electron spectroscopy and electron energy-loss spectroscopy. In this work, the results of the measurement of inner-shell ionization cross-sections by electron impact, Q, in a TEM are presented for the K shell.The measurement of QNi has been performed at 120 KeV in a TEM by measuring the net X-ray intensity of the Kα line of Ni, INi, which is related to QNi by the relation :(1)where i is the total electron dose, (Ω/4π)is the fractional solid angle, ω is the fluorescence yield, α is the relative intensity factor, ε is the Si (Li) detector efficiency, A is the atomic weight, ρ is the sample density, No is Avogadro's number, t' is the distance traveled by the electrons in the specimen which is equal to τ sec θ neglecting beam broadening where τ is the specimen thickness and θ is the angle between the electron beam and the normal of the thin foil and CNi is the weight fraction of Ni.

The German Strengths and Difficulties Questionnaire (SDQ)

2010 ◽  
Vol 26 (4) ◽  
pp. 256-262 ◽  
Author(s):  
Ulrike Petermann ◽  
Franz Petermann ◽  
Ina Schreyer
Keyword(s):  
Correlation Analysis ◽  
Teacher Ratings ◽  
Screening Instrument ◽  
Preschool Age ◽  
Strengths And Difficulties Questionnaire ◽  
Preschool Age Children ◽  
Discriminant Analyses ◽  
Strengths And Difficulties ◽  
Behavioral Attributes ◽  
And Behavior

The Strengths and Difficulties Questionnaire (SDQ) is a screening instrument that addresses positive and negative behavioral attributes of children and adolescents. Although this questionnaire has been used in Germany to gather information from parents and teachers of preschoolers, few studies exist that verify the validity of the German SDQ for this age. In the present study, teacher ratings were collected for 282 children aged 36 to 60 months (boys = 156; girls = 126). Likewise, teacher ratings were collected with another German checklist for behavior problems and behavior disorders at preschool age (Verhaltensbeurteilungsbogen für Vorschulkinder, VBV 3–6). Moreover, children’s developmental status was assessed. Evaluation included correlation analysis as well as canonical correlation analysis to assess the multivariate relationship between the set of SDQ variables and the set of VBV variables. Discriminant analyses were used to clarify which SDQ variables are useful to differentiate between children with or without developmental delay in a multivariate model. The results of correlation and discriminant analyses underline the validity of the SDQ for preschoolers. According to these results, the German teacher SDQ is recommended as a convenient and valid screening instrument to assess positive and negative behavior of preschool age children.

Dissociative excitation of molecules electron impact

1980 ◽  
Vol 77 ◽  
pp. 773-777 ◽  
Author(s):  
F.J. de Heer ◽  
H.A. Van Sprang ◽  
G.R. Mohlmann
Keyword(s):  
Electron Impact ◽  
Dissociative Excitation

Electron impact double ionization of neon

1993 ◽  
Vol 03 (C6) ◽  
pp. C6-117-C6-123 ◽  
Author(s):  
M. J. FORD ◽  
J. P. DOERING ◽  
J. W. COOPER ◽  
M. A. COPLAN ◽  
J. H. MOORE
Keyword(s):  
Electron Impact ◽  
Double Ionization

Electron impact excitation of Al XIII : Collision strengths and rate coefficients

2001 ◽  
Vol 11 (PR2) ◽  
pp. Pr2-309-Pr2-312
Author(s):  
K. M. Aggarwal ◽  
F. P. Keenan ◽  
S. J. Rose
Keyword(s):  
Electron Impact ◽  
Impact Excitation ◽  
Rate Coefficients ◽  
Electron Impact Excitation
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