Tomas Bata University in Zlín
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The issue of homeless young people as an alternative of life - Subjective evaluation of life on the street
Get PDFThis article is devoted to the issue of homeless young people as an alternative way of life on the street. Homelessness can understand as a complex generalized social failure of an individual characterized by their specific way of life, which puts them on the margins of society because of their inability to participate in their quality of life and disrespecting the requirements of the majority society. The aim of this article is to present the results of qualitative research related to the phenomenon of homeless young people and to understand the causes of their social decline in two areas of their life on the street, namely in the causes of home loss and subjective evaluation of the situation. Only professionally, provided social work can stop or reduce the number of young people living on the street and help them successfully reintegrate into mainstream society
Biodiesel from rapeseed and sunflower oil: Effect of the transesterification conditions and oxidation stability
Get PDFIn this study, we produced biodiesel fuel from two vegetal sources, rapeseed oil and sunflower oil, by transesterification reaction. The study aims to evaluate the impact of type of alcohol, its concentration and the reaction time, while keeping constant the temperature and the catalyst on the yield and quality of the biodiesel. For alcohol, methanol and ethanol were used at a molar ratio with the oil from 3 to 24. Transesterification was performed at various reaction times; 20, 40, 60 and 90 min for each oil and defined alcohol:oil molar ratio. The influence of these parameters on the biodiesel yield and properties were investigated in terms of density, viscosity, heating value, flash point, elemental content, density and oxidative stability of the final product. The benefit of oxidation stabilizers, catechol and 4-allyl-2,6-dimethoxyphenol was investigated. Results demonstrate that for rapeseed oil, the optimum reaction conditions to obtain a higher yield and quality of biodiesel were an alcohol:oil molar ratio of 15:1, with 60-min reaction time at 50 degrees C; while in the case of sunflower oil, the best yield and biodiesel quality were at an 18:1 molar ratio, with a 40-min reaction time and at 50 degrees C. In both cases, methanol provides the highest yields of biodiesel, and the obtained products satisfy the required standards and present a similarity with mineral diesel tested in same conditions.Ministry of Education and Science of the Russian Federation, Minobrnauka: 075-03-2021-287/6, WSWW-2020-0011Ministry of Education and Science of the Russian Federation [075-03-2021-287/6]; Ministry of Science and Higher Education of the Russian Federation: Science [WSWW-2020-0011
Study of light transmission and noise attenuation properties of light active glass materials
Get PDFLighting and noise belong to important environmental factors that have an influence on human psyche, concentration, labour protection, sleep quality and so on. This paper is focused on study of light transmission and noise attenuation properties of light active glass materials, which are applied as window and door panels in residential buildings. The light transmission through tested materials was evaluated by means of the transmission coefficient from the illuminance ratio method. The material ability to dampen noise was determined based on the sound pressure level attenuation during sound propagation through the light active glass materials. Different factors, which have an influence on the propagation of light and noise through the investigated glass materials, were evaluated in this work. Finally, the effect of the light transmission through the tested light active glass materials on the daylight quality in a living room was mathematically simulated using Wdls 5.0 software
Properties of quaternized and crosslinked carboxymethylcellulose films
Get PDFThe sodium salt of carboxymethylcellulose (CMC Na) is a suitable water-soluble derivative for the preparation of quaternized and crosslinked films. In this study, we prepared quaternized and crosslinked CMC Na (QCCMC) films, along with only quaternized (QCMC) and only crosslinked CMC Na (CCMC) derivatives, using one-step synthesis. The derivatives were characterized by high-resolution nuclear magnetic resonance (NMR) spectroscopy. Size-exclusion chromatographic multi-angle laser light scattering (SEC-MALS) revealed the solubilities of the studied derivatives: CMC Na (98.0%) > CCMC (81.2%) > QCMC (78.2%) > QCCMC (77.4%), while the gyration radii (R-g) of the polysaccharide coils were: CMC Na (20-78 nm) >= QCCMC (20-65 nm) >= QCMC (25-45 nm) & GE; CCMC (24-40 nm). Cyclic voltammetry distinguished all four types of derivatives with constant delta E, I-a and I-c parameters. X-ray diffraction confirmed that all of the prepared films were in an amorphous state. PeakForce quantitative nanomechanical mapping (PF-QNM) was used to study the film surface morphology and film surface mechanical properties of all of the prepared carboxymethylcellulose derivatives. The following decreasing orders were found for root mean square surface films roughness: CCMC (6.5 nm) > CMC Na (6.4 nm) > QCMC (4.1 nm) > QCCMC (2.0 nm); films reduced elastic modulus: CCMC (9.3 GPa) > QCCMC (8.0 GPa) > CMC Na (7.0 GPa) > QCMC (2.1 GPa); films stiffness: CCMC (66.8 N/m) > CMC Na (55.4 N/m) > QCCMC (53.9 N/m) > QCMC (20.5 N/m) and films adhesion: CCMC (25.7 nN) > CMC Na (21.4 nN) > QCMC (17.1 nN) > QCCMC (11.5 nN).Slovenská Akadémia Vied, SAV: 1/0489/16, 2/0071/22; Grantová Agentura České Republiky, GA ČR: 19-06065 SGrant Agency of Slovak Academy of Sciences VEGA; Czech Science Foundation [2/0071/22, 1/0489/16]; [19-06065 S
Przegląd zastosowań nanoanten
No full textCurrently, nanoantennas represent significant potential for the future, and the scientific community is putting a lot of effort into developing these devices. Many publications deal with different types such as plasmonic, dielectric, or hybrid, and structures of nanoantennas such as dipole, Yagi-Uda, and others; therefore, the idea arose to create an article summarizing the possibilities of using these devices in the last five years. The paper focuses on a brief description of currently investigated types of antennas, especially in the scientific field, and lists the most common applications of nanoantennas
Percentage ratios of cutting forces during high-reed face milling
Get PDFThis research paper is concerned with the experimental study of high-feed end milling of 1.4541 (X6CrNiTi18-10) stainless steel with replaceable cermet plates. Several machining operations were performed under different cutting conditions. The variable values were depth of cut, feed per tooth and cutting speed. The results were analyzed, and cutting forces were evaluated for dependence on cutting conditions (cutting speed, depth of cut, feed per tooth). The obtained data were statistically processed and plotted in graphs. It was found that the percentage distribution of cutting forces changed as the tool load increased. The ratio of forces acting in individual axes also changed with varying trends. An increasing trend was recorded in the x and y axes, while a decreasing trend was recorded in the z axis. Measured change, approximately 10%, can no longer be neglected as it can significantly influence the clamping stability of a part.IGA/FT/2023/005TBU of the Zlin Internal Grant Agency [IGA/FT/2023/005
IPSAS, IFRS, and the quality of the accounting — with an accent on public management
Get PDFAre accounting errors caused by national accounting standards? The goal of this paper is to identify the problems with the quality of accounting information when the new Czech accounting standards are used in the public sector. The aim is then to compare the impact of IPSAS and IFRS on the Czech accounting standards and the accounting error rate of private entities and public sector entities. Data analyzed in this paper were obtained in 2018 and 2019. The results of quantitative research are subjected to statistical testing in order to answer the research questions as well as identify differences between profit and non-profit (public sector) organizations. Results indicate that the impact of Czech GAAP on the occurrence of accounting errors is not statistically significant for either business or public sector entities. In addition, according to respondents, the Czech accounting standards after the public finance accounting reform are not considered to be the usual cause of errors in accounting. Actually, compliance with the updated Czech GAAP improves the quality of the financial statements and avoids errors when preparing financial statements. These findings are in line with several existing papers and thus support the existing idea that IPSAS or IFRS application promotes the quality of accounting. © 2022, Bucharest University of Economic Studies Publishing House. All rights reserved
A decision-making support model for financing start-up projects by venture capital funds on a crowdfunding platform
No full textThe main goal of this study is to develop a comprehensive decision support model for financing start-up projects by venture capital funds on a crowd-investment platform. The model is aimed at supporting decision-making processes by venture capital funds regarding the financing of expensive start-up projects on crowdfunding platforms. The decision support model will prevent biased conclusions of crowdfunding platform experts regarding the evaluation of start-up projects, and venture capital funds will be able to manage the decision support process at all stages of evaluation. The research results were verified and tested using the example of evaluating a real start-up project to make a decision on its financing by a venture capital fund. The study outcomes may be beneficial for all sides of the explored fields - from regulatory authorities through traditional investors to start-up initiatives - to carry out investment activities and to develop optimal strategies
Catalytic performance of micro-mesoporous zirconosilicates prepared by non-hydrolytic sol-gel in ethanol-acetaldehyde conversion to butadiene and related reactions
Get PDFThe open porosity and number of Lewis acid sites in metal silicates (M = Zr, Ta) have been reported as key factors enabling reaching high butadiene (BD) productivity from ethanol. However, some microporous zeolites recently displayed very high BD yields. To gain a deeper insight, we have applied non-hydrolytic sol-gel (NHSG) in the preparation of micro-mesoporous zirconosilicates. The porosity, structure, and acidity of these materials have been described and compared to a benchmark sample prepared by dry impregnation. The detailed characterization proved that NHSG preparation provided highly homogeneous Zr dispersion in silica leading to almost doubled Lewis acid site numbers and higher activity in ethanol-acetaldehyde conversion to BD, MeerweinPonndorf-Verley (MPV) reaction, and aldol condensation, in comparison to the catalyst prepared by dry impregnation. The selectivity and stability were similar for catalysts prepared by NHSG and dry impregnation.RP/CPS/2022/007; Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT: LM2018110, LM2018127; Grantová Agentura České Republiky, GA ČR: GJ20-03636Y; Central European Institute of Technology, CEITEC: CZ.02.1.01/0.0/0.0/18_046/0015586, LM2018124Czech Science Foundation [GJ20-03636Y]; CIISB; Instruct-CZ Centre of Instruct- ERIC EU consortium - Ministry of Education, Youth and Sports of the Czech Republic Infrastructure project [LM2018127, LM2018110]; Ministry of Education, Youth and Sports of the Czech Republic and the European Structural and Investments Funds; Ministry of Education, Youth and Sports of the Czech Republic-DKRVO [RP/CPS/2022/007
Fractional viscoelastic models of porcine skin and its gelatin-based surrogates
Get PDFViscoelasticity of porcine skin and its material substitute, modelled by variously concentrated bovine gelatin, was determined in static (creep test) and dynamic (oscillatory test) mode by the means of rotational rheometry to obtain creep compliance and complex shear modulus. Mechanical properties characterization was also supple-mented with large deformation compression test in order to determine and correlate shear and compression moduli of gelatin with its concentration dependence. Obtained data was fitted with fractional viscoelastic models (Poynting-Thomson, Maxwell) in order to quantify in detail gelatin's transition from viscous-like behavior to-wards solid-like state with increasing gelatin concentration and hence crosslinking density. Potential of gelatin as biomaterial for skin surrogate was identified as well as a concentration region in which gelatin exhibits closest viscoelastic behavior to native porcine skin used.Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT; Grantová Agentura České Republiky, GA ČR: 23-07244SMinistry of Education, Youth and Sports of the Czech Republic [RP/CPS/2022/007]; Czech Science Foundation [23-07244S