scholarly journals Using the Asymmetric Gaussian Method to Interpret the Electronic Spectroscopy of the Olivine Family

2021 ◽  
Author(s):  
Adrian Brown
Keyword(s):  
Electronic Spectroscopy ◽  
Gaussian Shape ◽  
Gaussian Curve ◽  
Fitting Method ◽  
Gaussian Method ◽  
Minimization Methods ◽  
Gaussian Fit ◽  
Numerical Minimization ◽  
First Time ◽  
Spectral Complex

Abstract This paper discusses the mathematical aspects of band fitting and introduces the Asymmetric Gaussian curve and its tangent space for the first time. First, we derive an equation for an Asymmetric Gaussian shape. We then derive a rule for the resolution of two Gaussian shaped bands. We then use the Asymmetrical Gaussian equation to derive a Master Equation to fit two overlapping bands. We identify regions of the fitting space where the Asymmetric Gaussian fit is optimal, sub optimal and not optimal. We then demonstrate the use of the Asymmetric Gaussian curve to fit four overlapping Gaussian bands, and show how this is relevant to the olivine family spectral complex at 1 μm. We develop a modified model of the olivine family spectral complex based on previous work by Runciman and Burns. The limitations of the asymmetric band fitting method and a critical assessment of three commonly used numerical minimization methods are also provided.

Using A Segmented Voltage Sweep Mode and A Gaussian Curve Fitting Method to Improve Heavy Metal Measurement System Performance

2012 ◽  
Vol 19 (2) ◽  
pp. 381-394
Author(s):  
José Pereira ◽  
Octavian Postolache ◽  
Pedro Girão
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Measurement System ◽  
Curve Fitting ◽  
System Performance ◽  
Redox Potentials ◽  
Voltage Sweep ◽  
Gaussian Curve ◽  
Fitting Method ◽  
Curve Fitting Method

Using A Segmented Voltage Sweep Mode and A Gaussian Curve Fitting Method to Improve Heavy Metal Measurement System PerformanceThis paper presents a voltammetric segmented voltage sweep mode that can be used to identify and measure heavy metals' concentrations. The proposed sweep mode covers a set of voltage ranges that are centered around the redox potentials of the metals that are under analysis. The heavy metal measurement system can take advantage of the historical database of measurements to identify the metals with higher concentrations in a given geographical area, and perform a segmented sweep around predefined voltage ranges or, alternatively, the system can perform a fast linear voltage sweep to identify the voltammetric current peaks and then perform a segmented voltage sweep around the set of voltages that are associated with the voltammetric current peaks. The paper also includes the presentation of two auto-calibration modes that can be used to improve system's reliability and proposes the usage of a Gaussian curve fitting of voltammetric data to identify heavy metals and to evaluate their concentrations. Several simulation and experimental results, that validate the theoretical expectations, are also presented in the paper.

Preparation of New Anti-Slip Flooring Coatings: Hydrophobic MMA Floor Coatings

2013 ◽  
Vol 721 ◽  
pp. 73-76
Author(s):  
Shu Le Lin ◽  
Hui Hua Cai
Keyword(s):  
Electronic Spectroscopy ◽  
Dynamic Contact ◽  
Contact Angles ◽  
Coating Properties ◽  
Hydrophobic Properties ◽  
X Ray ◽  
H Nmr ◽  
Potential Applications ◽  
Ft Ir ◽  
First Time

For the first time, hydrophobic MMA floor coatings were prepared based on the fluorine-containing methacrylic ester copolymers and applied as a new kind of anti-slip flooring coatings. The composition of the synthesized copolymers was characterized by FT-IR and 1H-NMR. The prepared hydrophobic MMA floor coatings were analyzed for their coating properties. The hydrophobic properties of the coatings were characterized by static and dynamic contact angles and X-ray photo-electronic spectroscopy (XPS). Results show that the newly prepared floor coatings are easy to apply and have excellent mechanical and hydrophobic properties, which indicates that the hydrophobic MMA floor coatings have great potential applications in anti-slip flooring coatings.

Synthesis and photophysical properties of zinc phthalocyanines substituted with quinolinoxy group

2009 ◽  
Vol 13 (12) ◽  
pp. 1206-1213 ◽  
Author(s):  
Jinping Xue ◽  
Lixuan Cai ◽  
Naisheng Chen ◽  
Jinling Huang
Keyword(s):  
Absorption Spectra ◽  
Electronic Absorption ◽  
Elemental Analysis ◽  
Fluorescence Spectra ◽  
Electronic Absorption Spectra ◽  
Photophysical Properties ◽  
Electronic Spectroscopy ◽  
Zinc Phthalocyanines ◽  
New Compounds ◽  
First Time

The synthesis of tetrasubstituted zinc phthalocyanines bearing quinolinoxy groups are reported for the first time. The new compounds have been characterized by elemental analysis, IR, MS and electronic spectroscopy. The photophysical properties, such as the electronic absorption spectra and fluorescence spectra, have also been investigated and discussed together with the influence of substituent position and organic solvents on these properties. The introduction of quinolinoxy group to the Pc ring was found to affect these photophysical properties to some extent.

scholarly journals Calibration and accuracy analysis of a focused plenoptic camera

2014 ◽  
Vol II-3 ◽  
pp. 205-212 ◽  
Author(s):  
N. Zeller ◽  
F. Quint ◽  
U. Stilla
Keyword(s):  
Curve Fitting ◽  
Depth Map ◽  
Reference Points ◽  
New Methods ◽  
Model Based ◽  
Depth Images ◽  
Fitting Method ◽  
Plenoptic Camera ◽  
Curve Fitting Method ◽  
First Time

In this article we introduce new methods for the calibration of depth images from focused plenoptic cameras and validate the results. We start with a brief description of the concept of a focused plenoptic camera and how from the recorded raw image a depth map can be estimated. For this camera, an analytical expression of the depth accuracy is derived for the first time. In the main part of the paper, methods to calibrate a focused plenoptic camera are developed and evaluated. The optical imaging process is calibrated by using a method which is already known from the calibration of traditional cameras. For the calibration of the depth map two new model based methods, which make use of the projection concept of the camera are developed. These new methods are compared to a common curve fitting approach, which is based on Taylor-series-approximation. Both model based methods show significant advantages compared to the curve fitting method. They need less reference points for calibration than the curve fitting method and moreover, supply a function which is valid in excess of the range of calibration. In addition the depth map accuracy of the plenoptic camera was experimentally investigated for different focal lengths of the main lens and is compared to the analytical evaluation.

scholarly journals Multiple cyclotron line-forming regions in GX 301−2

2018 ◽  
Vol 620 ◽  
pp. A153 ◽  
Author(s):  
F. Fürst ◽  
S. Falkner ◽  
D. Marcu-Cheatham ◽  
B. Grefenstette ◽  
J. Tomsick ◽  
...  
Keyword(s):  
Relativistic Effects ◽  
Resonant Scattering ◽  
The Other ◽  
High Mass ◽  
Good Resolution ◽  
Gaussian Shape ◽  
X Ray ◽  
Cyclotron Line ◽  
First Time ◽  
The Continuum

We present two observations of the high-mass X-ray binary GX 301−2 with NuSTAR, taken at different orbital phases and different luminosities. We find that the continuum is well described by typical phenomenological models, like a very strongly absorbed NPEX model. However, for a statistically acceptable description of the hard X-ray spectrum we require two cyclotron resonant scattering features (CRSF), one at ∼35 keV and the other at ∼50 keV. Even though both features strongly overlap, the good resolution and sensitivity of NuSTAR allows us to disentangle them at ≥99.9% significance. This is the first time that two CRSFs have been seen in GX 301−2. We find that the CRSFs are very likely independently formed, as their energies are not harmonically related and, if the observed feature were due to a single line, the deviation from a Gaussian shape would be very large. We compare our results to archival Suzaku data and find that our model also provides a good fit to those data. We study the behavior of the continuum as well as the CRSF parameters as function of pulse phase in seven phase bins. We find that the energy of the 35 keV CRSF varies smoothly as a function of phase, between 30 and 38 keV. To explain this variation, we apply a simple model of the accretion column, taking into account the altitude of the line-forming region, the velocity of the in-falling material, and the resulting relativistic effects. We find that in this model the observed energy variation can be explained as being simply due to a variation of the projected velocity and beaming factor of the line-forming region towards us.

A Statistical Analysis of X-ray Stress Measurement by the Gaussian Curve-Fitting Method

1981 ◽  
Vol 9 (5) ◽  
pp. 285 ◽  
Author(s):  
R Horstman ◽  
KA Peters ◽  
BM Schindler ◽  
RL Meltzer ◽  
M Bruce Vieth ◽  
...  
Keyword(s):  
Statistical Analysis ◽  
Curve Fitting ◽  
Stress Measurement ◽  
X Ray ◽  
Gaussian Curve ◽  
Fitting Method ◽  
Curve Fitting Method

An Estimation of Hardness of Hardened Steels by X-Ray Diffraction Using a Gaussian Curve-Fitting Method

1984 ◽  
Vol 12 (1) ◽  
pp. 13 ◽  
Author(s):  
R Horstman ◽  
KA Peters ◽  
RL Meltzer ◽  
MB Vieth ◽  
M Kurita ◽  
...  
Keyword(s):  
Curve Fitting ◽  
X Ray Diffraction ◽  
Hardened Steels ◽  
X Ray ◽  
Gaussian Curve ◽  
Fitting Method ◽  
Curve Fitting Method

scholarly journals “Global” analysis of 24 ro-vibrational bands of the octad of the 76GeH4 molecule

2020 ◽  
pp. 95-103
Author(s):  
N.I. Raspopova ◽  
◽  
O.V. Gromova ◽  
E.S. Bekhtereva ◽  
M.A. Koshelev ◽  
...  
Keyword(s):  
Potential Function ◽  
Global Analysis ◽  
Planetary Science ◽  
Interaction Parameters ◽  
Fitting Method ◽  
Vibrational Bands ◽  
First Time ◽  
Global Fitting Method ◽  
Global Fitting

A “global fitting” method was developed within the framework of the “SPHETOM” software implemented at the Tomsk Polytechnic University using the GeH4 molecule of T d symmetry as an example. Set of interacting states (so-called octad of interacting states) is chosen as the object of application. Band centers, rotational and resonance interaction parameters of all 24 sub-bands of the octadwere determined for the first time. Obtained information is important both for high-accurate intramolecular potential function determination of the germane molecule, andfor applications in planetary science and astrophysics.

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