Tomas Bata University in Zlín
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Crystallization kinetics and structural properties of nanocrystalline europium-yttrium-titanate (Eu0.5Y0.5)2Ti2O7
Get PDFWe present a versatile sol–gel approach for nanocrystalline (Eu0.5Y0.5)2Ti2O7. We determined the crystallization kinetics of the nucleation and the nucleation mechanism. The crystallization temperature was 1050.1 ± 0.8 K, and the activation energy of crystallization was 605 kJ mol−1. The nanocrystal growth started by homogenous nucleation with a constant nucleation rate, and the nanocrystal growth was limited by mass transfer through the phase boundary. The crystal structure of (Eu0.5Y0.5)2Ti2O7 was refined from the powder diffraction data using the Rietveld method, and the results were compared with the data recorded for the isostructural compounds, Eu2Ti2O7 and Y2Ti2O7. We proved the existence of a single phase of (Eu0.5Y0.5)2Ti2O7 and the regular distribution of Eu3+ and Y3+ ions inside the crystal lattice. The results provide key information regarding the crystallization properties and crystal structure of nanocrystalline (Eu0.5Y0.5)2Ti2O7. This knowledge is necessary for preparing pure nanocrystalline powders with tailored structural properties that are suitable for photonic applications. © 2022 The Society of Powder Technology JapanGrantová Agentura České Republiky, GA ČR: 21-45431L, RVO67985831Czech Science Foundation [21-45431L]; Institute of Geology of the CAS Research Plan [RVO67985831]Czech Science Foundation [21-45431L]; Institute of Geology of the CAS Research Plan [RVO67985831
Observation of residues content after application of a medium-chain fatty acids mixture at the end of alcoholic fermentation
Get PDFThis study focused on applying a patented medium-chain fatty acids (MCFAs) mixture at the end of alcoholic fermentation and monitoring its residues. MCFAs are a promising agent that has the potential to increase the efficiency of sulfur dioxide and ultimately minimize its doses, which is one of the important goals of wine research today. Detailed octanoic, decanoic, and dodecanoic acid contents were observed during the experiment. The MCFA mixture was applied at doses of 0, 10, 20, and 60 mg/L. GC-MS determined the content of individual fatty acids. The results showed that the use of the investigated mixture of fatty acids at doses of 10 and 20 mg/L did not cause an increase in the content of individual fatty acids residues. The octanoic acid content after application of the 20 mg/L MCFA mixture was 8.24 mg/L after 744 h, while the untreated control variant showed a value of 7.71 mg/L. The performed sensory analysis also did not show a negative effect of MCFA application on the sensory properties of wine. Therefore, applying an MCFA mixture at 10 and 20 mg/L can be recommended as a safe alternative following alcoholic fermentation. However, the results obtained can also serve as a valuable basis for permitting the use of MCFA in the proceeding OIV approval process. The research thus opens the possibility of expanding a new oenological agent capable of reducing SO2 doses.Operational Program Research, Development and Education [IGA-ZF/2021-SI1011, CZ.02.1.01/0.0/0.0/16_017/0002334
Use of foods based on bee drone brood: Their sensory and microbiological evaluation and mineral composition
Get PDFThe aim of the work was to evaluate the safety of bee drone brood in terms of the risk of possible contamination with heavy metals, microbial contamination, and sensory acceptability. Bee drone brood dried at a temperature of 80 degrees C in a hot air oven (DBO) and lyophilized drone brood (DBL) were used. Sensory evaluation was performed on an oatmeal ball (O-B) and drone brood ball (DBO-B). For the determination of the minerals and other elements in DBO, spectrometric analysis was used. The content was as follows: Fe 60.87 mu g/g, Cu 54.83 mu g/g, Zn 257 mu g/g, Ag 82.7 mu g/g, Pb 2.1 mu g/g, Au 1.2 mu g/g, Ca 1336 mu g/g, Sr 3.13 mu g/g, Zr 1.67 mu g/g, Bi 3.87 mu g/g, Br 1.95 mu g/g. The detected content of lead in dry matter (2.1 mu g/g) was high above the limit set for crustaceans (0.4 mu g/g). By comparing microbial assay values, no statistically significant difference between freshly dried DBO and dried DBO after a month of storage was detected. Bee drone brood contains microbes far below the legal limits and it is a good source of calcium, iron, and zinc. Except for the juiciness, consumers rated O-B better than DBO-B. A statistically significant difference (p < 0.05) was found only in taste.FEKT-S-20-6215, IGA/FT/2022/004TBU in Zlin [IGA/FT/2022/004]; project BUT in Brno [FEKT-S-20-6215
How health-related messaging increase intentions to download and use mobile contact (COVID-19) tracing apps: Preliminary findings
Get PDFThis study contributes to current discussions regarding the use of digital solutions and especially (mobile) contact tracingcontact-tracing apps (MCTA) in COVID-19 containment. This study is timely because several countries around the world andworld, including African countriescountries, face an acute shortage of COVID-19 vaccines and as a result complimentary measures and innovative solutions like MCTA can be useful in the containment of COVID-19 disease pandemic. Towardsd this end, the current study integrates the health belief model (HBM) with the theory of reasoned action (TRA) to investigate MCTA acceptability based on data collected from online respondents in Nigeria. The results of the empirical analyses, using PLS-SEM, indicate that perceived disease vulnerability, perceived severity of the disease, but but not perceived barriers ofto taking action, are important determinants of attitude towardsd MCTA. The results further show that, while attitude is positively related to MCTA adoption intention, both perceived disease vulnerability and perceived severity of the disease indirectly contribute to MCTA adoption intention through attitude towardsd MCTA. Overall, the proposed research model explains about 58.8% variation in the intention to adopt MCTA and therefore shines a positive light on the topic that is critical for shaping COVID-19 messaging in different countries of the world and especially in African countries where COVID-19 testing and vaccination drive remain worryingly slow.IGA [IGA/FaME/2021/003]; RVO [MSMT-7778/2020
Implementation of current marketing communication tools into practice in the Czech and Slovak Republic
No full textThe aim of the article is to map out how much are used current marketing communication tools (guerrilla marketing, digital marketing, mobile marketing, viral marketing, word of mouth marketing, buzz marketing, product placement) in the Czech and Slovak market. Article is based on quantitative research realized in the form of online survey, which respondents were professionals in the marketing communication field (employees of full-service and specialized advertising agencies, people from marketing departments). © 2019, Springer Nature Switzerland AG
Ways to find employment and preferences in relation to a new job for university graduates of the Pilsen region in the Czech Republic
No full textThe aim of this article is to determine the most frequently used methods of job search among University Graduates in the Pilsen Region and to evaluate them according to the time horizon of getting a job. As the field of study may have a high impact on the results, the data will be presented with regard to the area of the graduate’s focus. These outputs will then be compared with secondary data on job search patterns in selected regions of Europe from comparable published research. The article also focuses on identifying graduate preferences with regard to future employment as well as on gender and the field of study. The article is based on the partial results of research investigating the application of graduates in the Pilsen Region in the Czech Republic. The target group of the research was University Graduates, who graduated from the Bachelor’s degree program in 2012–2016 and have been living in the Pilsen Region. The sample consists of 272 respondents studying different study fields at universities. The outputs presented in this article can support the work of HR professionals who deal with recruitment and acquisition of talents among the University Graduates in the Pilsen Region. © 2019, Springer Nature Switzerland AG
Controllable modification of the BaTiO3 nanoparticles using SI-ATRP approach and impact on the vibration sensing capabilities of their PVDF-based composites
Get PDFIn this contribution the ceramic nanoparticles, BaTiO3 (BT), were successfully and controllably coated with two monomers, poly(butyl acrylate) (PBA) and poly(methyl methacrylate) (PMMA) using SI-ATRP approach. The presence of the polymers on the surface was investigated using FTIR and TGA techniques. The molecular weight and polydispersity index were calculated from the gel permeation chromatography, while monomer conversion was confirmed using nuclear magnetic resonance. Both methods provide clear statement that controlled radical polymerization was successful. The surface of the neat BT, BT-PBA and BT-PMMA nanoparticles was investigated using BET analysis and using contact angle. The nanoparticles were mixed with poly(vinylidene fluoride) (PVDF) using micro compounder. The compatibility of the nanoparticles and PVDF matrix was evaluated investigation of the viscoelastic properties using dynamic mechanical analyzer. The contribution of the enhanced compatibility between the nanofiller and matrix was elucidated by electrical response to vibration testing. Finally, it will be presented how the SI-ATRP modification of BT nanoparticles with PBA and PMMA influence the capability for vibration sensing applications. © 2021 NANOCON Conference Proceedings - International Conference on Nanomaterials. All rights reserved.Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT: RP/CPS/2020/003; Grantová Agentura České Republiky, GA ČR: 19-17457
Robot testing from a machine learning perspective
No full textThe need to scale software test automation while managing the test automation process within a reasonable time frame remains a crucial challenge for software development teams (DevOps). Unlike hardware, the software cannot wear out but can fail to satisfy the functional requirements it is supposed to meet due to the defects observed during system operation. In this era of big data, DevOps teams can deliver better and efficient code by utilizing machine learning (ML) to scan their new codes and identify test coverage gaps. This study introduces robot testing and machine learning to manage the test automation process to guarantee software reliability and quality within a reasonable timeframe.Univerzita Tomáše Bati ve Zlíně: IGA/CebiaTech/2021/001Internal Grant Agency of the Tomas Bata University in Zlin [IGA/CebiaTech/2021/001]; Faculty of Applied Informatics, Tomas Bata University in Zli
Poly(lactic acid) (PLA)-based nanocomposites: Impact of vermiculite, silver, and graphene oxide on thermal stability, isothermal crystallization, and local mechanical behavior
Get PDFThe structural, thermal, and mechanical properties of unreinforced and reinforced polylactic acid (PLA) were investigated. The PLA was a biopolymer that was reinforced with four fillers (i.e., graphene oxide (GO) and silver (Ag); vermiculite (VMT) and silver (Ag); and two organically modified vermiculites). The processing technique for the production of the composite materials were carefully planned. The PLA nanocomposites were investigated by examining their morphological aspects, changes in PLA phases and transitions and, most importantly, the effect on certain final properties. X-ray diffraction and differential scanning calorimetry (DSC) analysis indicated that the sample was completely amorphous. Thermogravimetric analysis (TGA) results indicated that the presence of reinforcing particles in the PLA matrix did not affect the thermal degradation of these composites. Furthermore, the local mechanical properties were investigated using the microindentation method to evaluate the effect of different nanofillers. Scanning electron microscopy (SEM) and a VHX-500 optical digital microscope (Keyence International, Mechelen, Belgium) were also used to examine the surface morphology of the PLA polymer composites. These results can help to select suitable fillers to enhance the PLA performance of biopolymers.Ministry of Education of the Czech RepublicMinistry of Education, Youth & Sports - Czech Republic [SP2019/23, SP2020/70]; ENSTA Bretagne; Technical University of Ostrava in the framework of Campus FranceMinisterstvo Školství, Mládeže a Tělovýchovy, MŠMT: SP2019/23, SP2020/7
Adsorption of estrogenic hormones in aqueous solution using electrospun nanofibers from waste cigarette butts: Kinetics, mechanism, and reusability
Get PDFThis study emphasizes rapid and simultaneous adsorptive removal of estrogenic hormones (EH): estrone (E1), estradiol (E2), ethinylestradiol (EE2), and estriol (E3) from wastewater using recycled waste cigarette electrospun fibers (WCENFs). The submicron fibers exhibited a strong affinity towards all EH due to abundant hydrogen bonding interactions. The adsorption kinetics pseudo-first-order, pseudo-second-order, intra-particle diffusion, Elovich, and fractional power models were explored and fitted towards optimum conditions for the large-scale removal process of the EH. Results showed that E1, E2, and EE2 followed pseudo-second-order kinetics while E3 followed the pseudo-first-order kinetic model. In combination, the total adsorption capacity achieved was 2.14 mg/g, whereas the individual values for E1, E2, EE2, and E3 were 0.551, 0.532, 0.687, and 0.369 mg/g, respectively. The percentage efficiency of WCENFs was highest with EE2-64.3% and least with E3-34.6%. The WCENFs could repeatedly be used for four adsorption-desorption cycles as an effective adsorbent for the simultaneous removal of four EH via batch adsorption studies. According to the results obtained, the repurposing of waste cigarette butts to WCENFs presented itself as a suitable alternative for removing EH and possibly other organic pollutants from water.Ministry of Education, Youth, and Sports of the Czech RepublicMinistry of Education, Youth & Sports - Czech Republic [RP/CPS/2020/002]; Internal Grant Agency of TBU in Zlin [IGA/CPS/2021/002]IGA/CPS/2021/002; Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT: RP/CPS/2020/002; Univerzita Tomáše Bati ve Zlín