Fundamentals of Nonlinear Acoustical Techniques and Sideband Peak Count

2018 ◽  
pp. 1-88 ◽  
Author(s):  
Tribikram Kundu ◽  
Jesús N. Eiras ◽  
Weibin Li ◽  
Peipei Liu ◽  
Hoon Sohn ◽  
...  
Keyword(s):  
Peak Count

Quantitative EPMA of nitrogen : A tricky element in the electron-probe microanalyzer

1992 ◽  
Vol 50 (2) ◽  
pp. 1622-1623
Author(s):  
G.F. Bastin ◽  
H.J.M. Heijligers
Keyword(s):  
Background Subtraction ◽  
Electron Probe ◽  
Detection System ◽  
Higher Order ◽  
Light Elements ◽  
Strong Suppression ◽  
Electron Probe Microanalyzer ◽  
Quantitative Epma ◽  
Peak Count ◽  
Lead Stearate

Among the ultra-light elements B, C, N, and O nitrogen is the most difficult element to deal with in the electron probe microanalyzer. This is mainly caused by the severe absorption that N-Kα radiation suffers in carbon which is abundantly present in the detection system (lead-stearate crystal, carbonaceous counter window). As a result the peak-to-background ratios for N-Kα measured with a conventional lead-stearate crystal can attain values well below unity in many binary nitrides . An additional complication can be caused by the presence of interfering higher-order reflections from the metal partner in the nitride specimen; notorious examples are elements such as Zr and Nb. In nitrides containing these elements is is virtually impossible to carry out an accurate background subtraction which becomes increasingly important with lower and lower peak-to-background ratios. The use of a synthetic multilayer crystal such as W/Si (2d-spacing 59.8 Å) can bring significant improvements in terms of both higher peak count rates as well as a strong suppression of higher-order reflections.

The breakdown of the power-law frequency distributions for the hard X-ray peak count rates of solar flares

2013 ◽  
Vol 13 (12) ◽  
pp. 1482-1492 ◽  
Author(s):  
You-Ping Li ◽  
Wei-Qun Gan ◽  
Li Feng ◽  
Si-Ming Liu ◽  
A. Struminsky
Keyword(s):  
Power Law ◽  
Solar Flares ◽  
Frequency Distributions ◽  
X Ray ◽  
Peak Count

scholarly journals Weak lensing peak count as a probe of f(R) theories

2013 ◽  
Vol 430 (4) ◽  
pp. 2896-2909 ◽  
Author(s):  
V. F. Cardone ◽  
S. Camera ◽  
R. Mainini ◽  
A. Romano ◽  
A. Diaferio ◽  
...  
Keyword(s):  
Weak Lensing ◽  
Peak Count

Estimation of the peak count of actively controlled aircraft

1982 ◽  
Vol 19 (8) ◽  
pp. 698-700
Author(s):  
Norman J. Meyerhoff ◽  
Jeffrey Garlitz
Keyword(s):  
Peak Count

Improving the assessment of activity in samples with non-uniform distribution using the sum peak count rate

2013 ◽  
Vol 81 ◽  
pp. 76-80 ◽  
Author(s):  
Rares Suvaila ◽  
Iolanda Osvath ◽  
Octavian Sima
Keyword(s):  
Uniform Distribution ◽  
Count Rate ◽  
Peak Count

Profile separation in complex powder patterns

1982 ◽  
Vol 15 (2) ◽  
pp. 190-198 ◽  
Author(s):  
S. V. N. Naidu ◽  
C. R. Houska
Keyword(s):  
Least Squares ◽  
Curve Fitting ◽  
Numerical Differentiation ◽  
Step Procedure ◽  
Peak Enhancement ◽  
Overlapping Peaks ◽  
Least Squares Curve Fitting ◽  
Diffraction Patterns ◽  
Data Requirements ◽  
Peak Count

Diffraction patterns from multi-element alloys, composite materials, enriched ores and other materials involving a mix of several phases often contain regions of overlapping diffraction peaks. In many cases, the peaks can be separated by a combination of numerical differentiation of the data and non-linear least-squares curve-fitting techniques. The derivative provides a powerful but simple technique for distinguishing the number of peaks and their locations within a scramble. These results are required as input to a least-squares curve-fitting routine. The end result of this two-step procedure is a set of parameters that define the positions, shape, width and areas of the separate peaks. A statistical analysis of the data requirements indicates that a good second derivative can be obtained with a peak count in the ~ 105 range using raw data, and the ~ 104 range with digital smoothing. The use of less accurate analog scans is also discussed. Examples are given with overlapping peaks in a 2θ range of less than 1° . The theoretical results describing the data requirements, resolution, distortion effects, and peak enhancement are based upon a Pearson VII function which is capable of describing all shapes continuously between the Cauchy, modified Lorentzian and the Gaussian.

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