Industrial inspection of specular surfaces using a new calibration procedure

The flame ionisation detector response to C6-C11 aliphatic hydrocarbon solutions in carbon disulphide in the concentration range between 1.3-9.5 mg ml-1 retained lineary despite the excess of solvent entering the detector simultaneously with the analyte. Pure carbon disulphide exhibited a small positive detector response which did not interfere in calibration procedure and which, under certain GC conditions, inverted to negative values. This response was not proportional to the injected volume and was strongly influenced by the column temperature and/or bleed. On the basis of these findings, a method compatible with the widely used charcoal tube carbon disulphide desorption procedure was developed and evaluated. It consists of static desorption of the sum of aliphatic alkanes and cycloalkanes from the activated charcoal after which an internal standard is added to the supernatant eluate. The resulting carbon disulphide solution is analysed on a highly polar stationary phase 1,2,3-tris(2-cyanoethoxy)propane where the solvent and the analyte coelute in a single peak, the height of which is practically proportional to the sum of alkanes and cycloalkanes present. This also makes determinations of other substances present in the sample more simple. The field test of the proposed method yielded values comparable in precision and accuracy with a control infrared spectrophotometric method.

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Mass Spectrometric Calibration Procedure for Real-Time Detection of Lighter Hydrocarbons

Energies ◽

10.3390/en14082123 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2123

Author(s):

Makuachukwu F. Mbaegbu ◽

Puspa L. Adhikari ◽

Ipsita Gupta ◽

Mathew Rowe

Keyword(s):

Real Time ◽

Mass Spectrometer ◽

Calibration Procedure ◽

Mass Spectrometric ◽

Spectrometric Method ◽

Mass Selection ◽

Mass Spectrometric Method ◽

Mass Spectrometers ◽

Drilling Rig

Determining gas compositions from live well fluids on a drilling rig is critical for real time formation evaluation. Development and utilization of a reliable mass spectrometric method to accurately characterize these live well fluids are always challenging due to lack of a robust and effectively selective instrument and procedure. The methods currently utilized need better calibration for the characterization of light hydrocarbons (C1–C6) at lower concentrations. The primary goal of this research is to develop and optimize a powerful and reliable analytical method to characterize live well fluid using a quadruple mass spectrometer (MS). The mass spectrometers currently being used in the field have issues with detection, spectra deconvolution, and quantification of analytes at lower concentrations (10–500 ppm), particularly for the lighter (<30 m/z) hydrocarbons. The objectives of the present study are thus to identify the detection issues, develop and optimize a better method, calibrate and QA/QC the MS, and validate the MS method in lab settings. In this study, we used two mass spectrometers to develop a selective and precise method to quantitatively analyze low level lighter analytes (C1–C6 hydrocarbons) with masses <75 m/z at concentrations 10–500 ppm. Our results suggest that proper mass selection like using base peaks with m/z 15, 26, 41, 43, 73, and 87, respectively, for methane, ethane, propane, butane, pentane, and hexane can help detect and accurately quantify hydrocarbons from gas streams. This optimized method in quadrupole mass spectrometer (QMS) will be invaluable for early characterization of the fluid components from a live hydrocarbon well in the field in real time.

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Simple Index to Assess the Calibration Quality of Safety Performance Functions Based on Multiple Goodness-of-Fit Metrics

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/03611981211008896 ◽

2021 ◽

pp. 036119812110088

Author(s):

Raul E. Avelar ◽

Karen Dixon ◽

Boniphace Kutela ◽

Sam Klump ◽

Beth Wemple ◽

...

Keyword(s):

Goodness Of Fit ◽

Synthetic Data ◽

Calibration Procedure ◽

Safety Performance ◽

Absolute Deviation ◽

Data Set ◽

Safety Database ◽

Simple Index ◽

Safety Performance Functions

The calibration of safety performance functions (SPFs) is a mechanism included in the Highway Safety Manual (HSM) to adjust SPFs in the HSM for use in intended jurisdictions. Critically, the quality of the calibration procedure must be assessed before using the calibrated SPFs. Multiple resources to aid practitioners in calibrating SPFs have been developed in the years following the publication of the HSM 1st edition. Similarly, the literature suggests multiple ways to assess the goodness-of-fit (GOF) of a calibrated SPF to a data set from a given jurisdiction. This paper uses the calibration results of multiple intersection SPFs to a large Mississippi safety database to examine the relations between multiple GOF metrics. The goal is to develop a sensible single index that leverages the joint information from multiple GOF metrics to assess overall quality of calibration. A factor analysis applied to the calibration results revealed three underlying factors explaining 76% of the variability in the data. From these results, the authors developed an index and performed a sensitivity analysis. The key metrics were found to be, in descending order: the deviation of the cumulative residual (CURE) plot from the 95% confidence area, the mean absolute deviation, the modified R-squared, and the value of the calibration factor. This paper also presents comparisons between the index and alternative scoring strategies, as well as an effort to verify the results using synthetic data. The developed index is recommended to comprehensively assess the quality of the calibrated intersection SPFs.

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A calibration procedure for the assessment of work hardening part I: Effects of the microstructure and load type

Materials Characterization ◽

10.1016/j.matchar.2021.111067 ◽

2021 ◽

Vol 175 ◽

pp. 111067

Author(s):

J.P. Goulmy ◽

E. Rouhaud ◽

P. Kanoute ◽

L. Toualbi ◽

S. Kruch ◽

...

Keyword(s):

Work Hardening ◽

Calibration Procedure

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A calibration procedure for a digital instrument for electric power quality measurement

IMTC 2001. Proceedings of the 18th IEEE Instrumentation and Measurement Technology Conference. Rediscovering Measurement in the Age of Informatics (Cat. No.01CH 37188) ◽

10.1109/imtc.2001.928823 ◽

2002 ◽

Cited By ~ 9

Author(s):

A. Ferrero ◽

M. Lazzaroni ◽

S. Salicone

Keyword(s):

Electric Power ◽

Power Quality ◽

Quality Measurement ◽

Calibration Procedure ◽

Digital Instrument ◽

Electric Power Quality

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Parasitic Loop Inductances Reduction in the PCB Layout in GaN-Based Power Converters Using S-Parameters and EM Simulations

Energies ◽

10.3390/en14051495 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1495

Author(s):

Loris Pace ◽

Nadir Idir ◽

Thierry Duquesne ◽

Jean-Claude De Jaeger

Keyword(s):

High Frequency ◽

Printed Circuit Board ◽

Power Converters ◽

Calibration Procedure ◽

Circuit Board ◽

Design System ◽

Switching Speed ◽

Parasitic Inductance ◽

Frequency Converters ◽

S Parameters

Due to the high switching speed of Gallium Nitride (GaN) transistors, parasitic inductances have significant impacts on power losses and electromagnetic interferences (EMI) in GaN-based power converters. Thus, the proper design of high-frequency converters in a simulation tool requires accurate electromagnetic (EM) modeling of the commutation loops. This work proposes an EM modeling of the parasitic inductance of a GaN-based commutation cell on a printed circuit board (PCB) using Advanced Design System (ADS®) software. Two different PCB designs of the commutation loop, lateral (single-sided) and vertical (double-sided) are characterized in terms of parasitic inductance contribution. An experimental approach based on S-parameters, the Cold FET technique and a specific calibration procedure is developed to obtain reference values for comparison with the proposed models. First, lateral and vertical PCB loop inductances are extracted. Then, the whole commutation loop inductances including the packaging of the GaN transistors are determined by developing an EM model of the device’s internal parasitic. The switching waveforms of the GaN transistors in a 1 MHz DC/DC converter are given for the different commutation loop designs. Finally, a discussion is proposed on the presented results and the development of advanced tools for high-frequency GaN-based power electronics design.

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