Determination of Parasitic Capacitances in Inductive Components - A Comparison Between Analytic Calculation Methods and FEM-Simulation

Background: The present study was focused on the development of HPLC method for purity testing of sofosbuvir by the Design of Experiments and determination of the activation energy of hydrolytic degradation reactions of sofosbuvir using HPLC based on the kinetics of sofosbuvir degradation. Methods: Following four factors for the Design of Experiments were selected, stationary phase, an organic modifier of the mobile phase, column temperature and pH of the mobile phase. These factors were examined in two or three level experimental design using Modde 11.0 (Umetrics) software. The chromatographic parameters like resolution, USP tailing and discrimination factor were calculated and analysed by partial least squares. The chromatography was performed based on Design of Experiments results with the mobile phase containing ammonium phosphate buffer pH 2.5 and methanol as an organic modifier. Separation was achieved using gradient elution on XBridge BEH C8 at 50 °C and a flow rate of 0.8 mL/min. UV detection was performed at 220 nm. The activation energy of hydrolytic degradation reactions of sofosbuvir was evaluated using two different calculation methods. The first method is based on the slope of dependence of natural logarithm of the rate constant on inverted thermodynamic temperature and the second approach is the isoconversional method. Results and Conclusion: Calculated activation energies were 77.9 ± 1.1 kJ/mol for the first method and 79.5 ± 3.2 kJ/mol for the isoconversional method. The results can be considered to be identical, therefore both calculation methods are suitable for the determination of the activation energy of degradation reactions.

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Determination of a stable lateral region of a floating disc – Mathematical analysis and FEM simulation

Alexandria Engineering Journal ◽

10.1016/j.aej.2021.01.053 ◽

2021 ◽

Vol 60 (3) ◽

pp. 3107-3118

Author(s):

Bharath Kumar Narukullapati ◽

Tapas Kumar Bhattacharya

Keyword(s):

Mathematical Analysis ◽

Fem Simulation ◽

Lateral Region

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Calculation methods and model experiments for the determination of the parameters of third (Peripheral) mixing chambers using the isotope dilution technique

Research in Experimental Medicine ◽

10.1007/bf01852172 ◽

1972 ◽

Vol 158 (2) ◽

pp. 95-122 ◽

Cited By ~ 1

Author(s):

H. Ludt ◽

H. D. Herrmann

Keyword(s):

Isotope Dilution ◽

Calculation Methods ◽

Dilution Technique ◽

Isotope Dilution Technique ◽

Model Experiments ◽

Mixing Chambers

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Advances In Calculation Methods For The Determination Of Surface Tensions In Drop Profile Analysis Tensiometry

Bubble and Drop Interfaces ◽

10.1163/ej.9789004174955.i-558.21 ◽

2011 ◽

pp. 39-60 ◽

Cited By ~ 3

Author(s):

S.A. Zholob ◽

A.V. Makievski ◽

V.B. Fainerman ◽

R. Miller

Keyword(s):

Profile Analysis ◽

Calculation Methods ◽

Surface Tensions ◽

Drop Profile Analysis Tensiometry

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FEM simulation and experimental determination of the temperature profile of nanoparticles excited by laser radiation

10.1117/12.2063838 ◽

2014 ◽

Author(s):

Nuno F. G. Rodrigues ◽

Carla Rosa ◽

João M. P. Coelho

Keyword(s):

Laser Radiation ◽

Experimental Determination ◽

Temperature Profile ◽

Fem Simulation

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Determination of rock hardness at the chrysotile - asbestos deposit

VIII Information school of a young scientist Central Scientific Library of the Urals Branch of the Russian Academy of Science ◽

10.32460/ishmu-2020-8-0002 ◽

2020 ◽

Author(s):

P.I. Zuev ◽

◽

V.S. Vedernikov ◽

D.V. Grigoriev ◽

◽

...

Keyword(s):

Economic Feasibility ◽

Open Pit ◽

Open Pit Mining ◽

Chrysotile Asbestos ◽

Calculation Methods ◽

Rock Hardness ◽

Technological Improvement

The article presents field and calculation methods for determining the rock hardness at the chrysotile-asbestos deposit mined by the open–pit mining. The methods presented are necessary for technological improvement of mining (including optimization of drilling and blasting operations), which, in the turn, improves the economic feasibility of the chrysotile-asbestos mining.

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Evaluation of Flange Calculations Using Strain-Based Acceptance Criteria

Volume 2: Computer Technology and Bolted Joints ◽

10.1115/pvp2019-93521 ◽

2019 ◽

Author(s):

Alexander Mutz ◽

Manfred Schaaf

Keyword(s):

Nuclear Power ◽

Power Plants ◽

Elastic Stress ◽

Calculation Methods ◽

Acceptance Criteria ◽

Class 1 ◽

Torque Moment ◽

Calculation Algorithms ◽

Calculation Code

Abstract The Nuclear Power Plant KKG in Gösgen, Switzerland was designed according to the ASME Boiler and Pressure Vessel Code. The ASME BPVC, Section III, Appendix 11 regulates the flange calculation for class 2 and 3 components, it is also used for class 1 flanges. A standard for the determination of the required gasket characteristics is not well established which leads to a lack of clarity. As a hint different y and m values for different kinds of gasket are invented in ASME BPVC Section III [1]. The KTA 3201.2[2] and KTA 3211.2[3] regulate the calculation of bolted flanged joints in German nuclear power plants. The gasket characteristics required for these calculation methods are based on DIN 28090-1[4], they can be determined experimentally. In Europe, the calculation code EN 1591-1 [5] and the gasket characteristics according to EN 13555[6] are used for flange calculations. Because these calculation algorithms provide not only a stress analysis but also a tightness proof, it would be preferable to use them also in the NPP’s in Switzerland. Additionally, for regulatory approval also the requirements of the ASME BPVC must be fullfilled. For determining the bolting up torque moment of flanges several tables for different nominal diameters of flanges using different gaskets and different combinations of bolt and flange material were established. As leading criteria for an allowable state, the gasket surface pressure, the allowable elastic stress of the bolts and the strain in the flange should be a good and conservative basis for determining allowable torque moments. The herein established tables show only a small part according to a previous paper [7] where different calculation methods for determining bolting up moments were compared to each other. In this paper the bolting-up torque moments determined with the European standard EN 1591-1 for the flange, are assessed on the strain-based acceptance criteria in ASME BPVC, Section III, Appendices EE and FF. The assessment of the torque moment of the bolts remains elastically which should lead to a more conservative insight of the behavior of the flanges.

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Modelling the thermal radiation from kitchen hob fires

Journal of Fire Sciences ◽

10.1177/0734904120923566 ◽

2020 ◽

Vol 38 (4) ◽

pp. 377-394

Author(s):

Michael Spearpoint ◽

Charlie Hopkin ◽

Danny Hopkin

Keyword(s):

Heat Flux ◽

Point Source ◽

Radial Distance ◽

Source Model ◽

View Factor ◽

Calculation Methods ◽

Fire Dynamics ◽

Potential Threat ◽

Computational Tools

Kitchen hob fires present a potential threat to occupants escaping from dwellings and calculations may be needed to assess the hazard. Determination of the thermal heat flux from flames to a target can be achieved through the use of hand calculation methods or computational tools. This article compares point source, parallel plane and cylindrical view factor hand calculations and computational simulations using B-RISK and Fire Dynamics Simulator of thermal heat flux with kitchen hob fire experiments presented in the literature. Knowing the level of accuracy of each method provides useful information to designers. Although the point source model is influenced by whether the radial distance is measured perpendicular to the heat flux target or is offset relative to the centre of the flame, the article concludes that it provides an adequate approach for the calculation of thermal heat flux in the case of kitchen hob fires.

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Bearing Capacity of Common and Damaged CFRP-Strengthened R. C. Beams Subject to High-Level Low-Cycle Loading

Materials Science Forum ◽

10.4028/www.scientific.net/msf.968.185 ◽

2019 ◽

Vol 968 ◽

pp. 185-199

Author(s):

Vasyl M. Karpiuk ◽

Yulia A. Syomina ◽

Diana V. Antonova

Keyword(s):

Bearing Capacity ◽

Repeated Loading ◽

Calculation Methods ◽

Design Standards ◽

Deformation Method ◽

Current Design ◽

Cycle Loading ◽

High Level ◽

Concrete Elements

In the course of operation or armed hostilities the span r.c. structures are subject to substantial damage and considerable reduction of their bearing capacity, especially under low-cycle repeated loading. In this connection it becomes necessary to renew their operation capacity and/or improve their bearing capacity. However, the current design standards contain no recommendations as to determination of the residual bearing capacity of such structures and calculation of their reinforcement. There are methods of the operation capacity renewal and reinforcement of the structures by increasing their sections adding metal or reinforced concrete elements. Still, the calculation methods of such reinforcement are also imperfect. It is proposed to renew operation capacity of such structures by strengthening their tensioned parts with CFRP; the performed experimental research will provide the basis for calculating bearing capacity of said structures with the aid of the deformation method improved by the authors.

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