Number of found documents: 15030
Published from to

Modification of cooling system for laboratory measurement of rotor blade vibration
Maturkanič, Dušan; Procházka, Pavel; Hodboď, Robert; Voronova, Evgeniya; Mekhalfia, Mohammed Lamine
2024 - English
Last year, the replacement of the turbine wheel model was completed in the Laboratory of Rotational Laser Vibrometry of the Institute of Thermomechanics AS CR, v.v.i. Based on previous experience and the expected higher operating load planned for the new wheel, the cooling system was modified at the same time. The paper describes the main effort in this direction and the results that clarify the previous damage of the measuring device. Keywords: blade; vibration; cooling system; measurement; laboratory Available at various institutes of the ASCR
Modification of cooling system for laboratory measurement of rotor blade vibration

Last year, the replacement of the turbine wheel model was completed in the Laboratory of Rotational Laser Vibrometry of the Institute of Thermomechanics AS CR, v.v.i. Based on previous experience and ...

Maturkanič, Dušan; Procházka, Pavel; Hodboď, Robert; Voronova, Evgeniya; Mekhalfia, Mohammed Lamine
Ústav termomechaniky, 2024

Stochastic version of the arc-length method
Náprstek, Jiří; Fischer, Cyril
2024 - English
The solution of a nonlinear algebraic system using the incremental method, based on pre-defined loading steps, fails in the vicinity of local extrema as well as around bifurcation points. The solution involved the derivation of the so-called ’Arc-Length’ method. Its essence lies in not incrementing the system parameter or any of the independent variables but rather the length of the response curve. The stochastic variant of this method allows for working with a system where system parameters include random imperfections. This contribution presents a variant that tracks the first two stochastic moments. Even in this simple case, interesting phenomena can be observed, such as the disappearance of the energy barrier against equilibrium jump due to random imperfections in the system. Keywords: random imperfection; stochastic arc-length method; continuation; numerical method Available in digital repository of the ASCR
Stochastic version of the arc-length method

The solution of a nonlinear algebraic system using the incremental method, based on pre-defined loading steps, fails in the vicinity of local extrema as well as around bifurcation points. The solution ...

Náprstek, Jiří; Fischer, Cyril
Ústav teoretické a aplikované mechaniky, 2024

Acoustic emission methods in steel bridge degradation identification and monitoring
Šorm, Filip
2024 - English
Acoustic emission methods proved to be an effective diagnostic tool in many industrial sectors. The potential of this method in the field of steel bridge diagnostics is explored in this article. The goal is to find the most effective use of this method. Keywords: steel bridges; diagnostics; acoustic emission Available in digital repository of the ASCR
Acoustic emission methods in steel bridge degradation identification and monitoring

Acoustic emission methods proved to be an effective diagnostic tool in many industrial sectors. The potential of this method in the field of steel bridge diagnostics is explored in this article. The ...

Šorm, Filip
Ústav teoretické a aplikované mechaniky, 2024

Multi-Annual Characterization of PM1 Aerosol Optical Properties and Size Distribution at the Peri-Urban Atmospheric Site ATOLL in Lille
Suchánková, Lenka
2024 - English
The aim of this study is to present aerosol scattering, absorption properties and particle number size distribution in PM1 in years 2018-\n2022 at peri-urban atmospheric site Atmospheric Observations in LiLLE (ATOLL) in Lille, France. This study is the first to present results dedicated to aerosol scattering properties at this site. Keywords: aerosol particles; PM1; temporal trends Available in digital repository of the ASCR
Multi-Annual Characterization of PM1 Aerosol Optical Properties and Size Distribution at the Peri-Urban Atmospheric Site ATOLL in Lille

The aim of this study is to present aerosol scattering, absorption properties and particle number size distribution in PM1 in years 2018-\n2022 at peri-urban atmospheric site Atmospheric Observations ...

Suchánková, Lenka
Ústav chemických procesů, 2024

Development of Continuous Technology for the Preparation of Pharmaceuticals
Jaklová, Natalie
2024 - English
The present research focuses on the transition of a batch reaction assisted by phase transfer catalyst (PTC) into continuous process. The first reaction studied was an N-alkylation reaction with methyl ester of the 1-methyl-10α-methoxydihydrolysergic acid (MeLUME) as product. MeLUME is one of the intermediates in synthesis of drug Nicergoline. The N-alkylation occurs in two different immiscible phases and the bridge between these phases is the phase transfer catalyst. The study was performed in several different continuous flow apparatuses. The best results were obtained in a capillary reactor, with assistance of ultrasound. Keywords: continualization; ultrasound; pharmaceuticals Available in a digital repository NRGL
Development of Continuous Technology for the Preparation of Pharmaceuticals

The present research focuses on the transition of a batch reaction assisted by phase transfer catalyst (PTC) into continuous process. The first reaction studied was an N-alkylation reaction with ...

Jaklová, Natalie
Ústav chemických procesů, 2024

Bubble Breakup in Triton Solutions
Semlerová, Tereza
2024 - English
This work deals with investigation of the bubble breakup in surfactant Triton X-45 solutions and the results are compared with data measured in water and α-terpineol solutions as another type of surfactants. Keywords: bubble breakup; surfactants; dynamic surface tension Available in digital repository of the ASCR
Bubble Breakup in Triton Solutions

This work deals with investigation of the bubble breakup in surfactant Triton X-45 solutions and the results are compared with data measured in water and α-terpineol solutions as another type of ...

Semlerová, Tereza
Ústav chemických procesů, 2024

Thin Film Photocatalysts on the Basis of g-C3N4
Schimon, Domonik
2024 - English
This study revolves around the synthesis of powder g-C3N4, fabricationof thin g-C3N4 films and their efficacy in degrading pollutants, assessed through experimentation in a batch photoreactor (BPR) and a slit geometry photomicroreactor (PMR)2. The photocatalytic activity of g-C3N4 was tested with 4 different model substances: fluorescent dye, rhodamine B, was used as a reference substance and three separate antibiotics, which are emerging wastewater pollutants, namely tetracycline, trimethoprim, sulfamethoxazole. Keywords: g-C3N4; photocatalysis; microreactor Available in a digital repository NRGL
Thin Film Photocatalysts on the Basis of g-C3N4

This study revolves around the synthesis of powder g-C3N4, fabricationof thin g-C3N4 films and their efficacy in degrading pollutants, assessed through experimentation in a batch photoreactor (BPR) ...

Schimon, Domonik
Ústav chemických procesů, 2024

Measurements of New Particle Formation in the Atmosphere
Špalová, Anna
2024 - English
In this work, the formation of particles and their transformation to larger sizes will be studied by measuring the concentration of molecular clusters. The measurement will take place at a rural background site National Atmospheric Observatory Košetice. At the ground level, a Neutral and Air Ion Spectrometer (NAIS) able to measure both neutral and charged clusters or particles ranging from 0.8 to 40 nm in diameter will be used together with a Particle Size Magnifier (PSM) able to measure neutral clusters as small as 1 nm in diameter up to 12 nm. Larger particles will be measured by a Scanning Mobility Particle Sizer (SMPS). At a height of 230 m above ground level, there will be another SMPS and also a nanoSMPS able to detect particles as small as 1 nm in diameter. Available in digital repository of the ASCR
Measurements of New Particle Formation in the Atmosphere

In this work, the formation of particles and their transformation to larger sizes will be studied by measuring the concentration of molecular clusters. The measurement will take place at a rural ...

Špalová, Anna
Ústav chemických procesů, 2024

Electrochemistry of Acetaminophen
Mikysek, T.; Ludvík, Jiří
2024 - English
The contribution is focused on electrochemical oxidation of acetaminophen mainly in non-aqueous media. The influence of various organic solvents as well as the pH effect is described herein. The redox properties of acetaminophen were studied by means of cyclic voltammetry, and rotating-disk voltammetry. We found that the protonation/deprotonation of acetaminophen acts as a ratedetermining step, where the stability of phenoxy radical intermediate plays an important role. Keywords: acetaminophen; phenacetine; voltammetry Available on request at various institutes of the ASCR
Electrochemistry of Acetaminophen

The contribution is focused on electrochemical oxidation of acetaminophen mainly in non-aqueous media. The influence of various organic solvents as well as the pH effect is described herein. The redox ...

Mikysek, T.; Ludvík, Jiří
Ústav fyzikální chemie J. Heyrovského, 2024

A New Approach to Determining the Drug Guaifenesin Using Voltammetric and Flow Injection Analysis
Kelíšková, P.; Matvieiev, O.; Sokolová, Romana; Janíková, L.; Behúl, M.; Šelešovská, R.
2024 - English
This study presents a new method for detecting guaifenesin (GFE) in pharmaceutical samples. We employed screen-printed sensors with a boron-doped diamond electrode (BDDE) to develop and validate both voltammetric and flow amperometric methods. These approaches were effectively used to analyze model solutions, pharmaceutical preparations, and serum samples spiked with GFE, producing accurate results comparable to those obtained with HPLC/DAD analysis. The developed methods provide straightforward, sensitive, and selective means for determining GFE in various sample matrices, underscoring the potential of SP/BDDE in electrochemical analysis. Keywords: guaifenesin; screen-printed sensor; boron-doped diamond electrode Available on request at various institutes of the ASCR
A New Approach to Determining the Drug Guaifenesin Using Voltammetric and Flow Injection Analysis

This study presents a new method for detecting guaifenesin (GFE) in pharmaceutical samples. We employed screen-printed sensors with a boron-doped diamond electrode (BDDE) to develop and validate both ...

Kelíšková, P.; Matvieiev, O.; Sokolová, Romana; Janíková, L.; Behúl, M.; Šelešovská, R.
Ústav fyzikální chemie J. Heyrovského, 2024

About project

NRGL provides central access to information on grey literature produced in the Czech Republic in the fields of science, research and education. You can find more information about grey literature and NRGL at service web

Send your suggestions and comments to nusl@techlib.cz

Provider

http://www.techlib.cz

Facebook

Other bases