Tomas Bata University in Zlín
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Copper phosphinate complexes as molecular precursors for ethanol dehydrogenation catalysts
Get PDFNowadays, the production of acetaldehyde heavily relies on the petroleum industry. Developing new catalysts for the ethanol dehydrogenation process that could sustainably substitute current acetaldehyde production methods is highly desired. Among the ethanol dehydrogenation catalysts, copper-based materials have been intensively studied. Unfortunately, the Cu-based catalysts suffer from sintering and coking, which lead to rapid deactivation with time-on-stream. Phosphorus doping has been demonstrated to diminish coking in methanol dehydrogenation, fluid catalytic cracking, and ethanol-to-olefin reactions. This work reports a pioneering application of the well-characterized copper phosphinate complexes as molecular precursors for copper-based ethanol dehydrogenation catalysts enriched with phosphate groups (Cu-phosphate/SiO2). Three new catalysts (CuP-1, CuP-2, and CuP-3), prepared by the deposition of complexes {Cu(SAAP)}n (1), [Cu6(BSAAP)6] (2), and [Cu3(NAAP)3] (3) on the surface of commercial SiO2, calcination at 500 °C, and reduction in the stream of the forming gas 5% H2/N2 at 400 °C, exhibited unusual properties. First, the catalysts showed a rapid increase in catalytic activity. After reaching the maximum conversion, the catalyst started to deactivate. The unusual behavior could be explained by the presence of the phosphate phase, which made Cu2+ reduction more difficult. The phosphorus content gradually decreased during time-on-stream, copper was reduced, and the activity increased. The deactivation of the catalyst could be related to the copper diffusion processes. The most active CuP-1 catalyst reaches a maximum of 73% ethanol conversion and over 98% acetaldehyde selectivity at 325 °C and WHSV = 2.37 h-1CF BIC; European Regional Development Fund-Project “UP CIISB, (CZ.02.1.01/0.0/0.0/18_046/0015974, LM2018110); Grant Agency of Masaryk University, (CZ.02.01.01/00/22_008/0004572, MUNI/A/1298/2022, MUNI/J/0007/2021, QM4ST); Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT, (LM2018127, LM2023042, LM2023056, RP/CPS/2022/007); Grantová Agentura České Republiky, GA ČR, (GJ20-03636Y); Central European Institute of Technology, CEITECMEYS CR [LM2023042, LM2018127, CZ.02.1.01/0.0/0.0/18_046/0015974]; European Regional Development Fund-Project "UP CIISB" [LM2018110]; Czech Science Foundation [GJ20-03636Y]; Grant Agency of Masaryk University [MUNI/J/0007/2021, MUNI/A/1298/2022]; Quantum Materials for Applications in Sustainable Technologies (QM4ST) [CZ.02.01.01/00/22_008/0004572]; Ministry of Education, Youth and Sports of the Czech Republic [LM2023056]; Ministry of Education, Youth and Sports of the Czech Republic [RP/CPS/2022/007
DFT study of water on graphene: Synergistic effect of multilayer p-doping
No full textRecent experiments related to a study concerning the adsorption of water on graphene have demonstrated the p-doping of graphene, although most of the ab initio calculations predict nearly zero doping. To shed more light on this problem, we have carried out van der Waals density functional theory calculations of water on graphene for both individual water molecules and continuous water layers with coverage ranging from one to eight monolayers. Furthermore, we have paid attention to the influence of the water molecule orientation toward graphene on its doping properties. In this article, we present the results of the band structure and the Bader charge analysis, showing the p-doping of graphene can be synergistically enhanced by putting 4-8 layers of an ice-like water structure on graphene having the water molecules oriented with oxygen atoms toward graphene.AMISPEC, (TE01020233); INCHAR, (FW03010504); Technology Agency of the Czech Republic, TACR; Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT; Grantová Agentura České Republiky, GA ČR, (23-07617S); Vysoké Učení Technické v Brně, BUT, (FSI-S-23-8324)Grant Agency of the Czech Republic; Ministry of Education, Youth and Sports from the Large Infrastructures for Research; Technology Agency of the Czech Republic [TE01020233]; Specific Research grant of the Brno University of Technology [FSI-S-23-8324]; [23-07617S]Grant Agency of the Czech Republic; Ministry of Education, Youth and Sports from the Large Infrastructures for Research; Technology Agency of the Czech Republic [TE01020233]; Specific Research grant of the Brno University of Technology [FSI-S-23-8324]; [23-07617S
Sage essential oil as an antimicrobial agent against salmonella enterica during beef sous vide storage
Get PDFSous-vide is a process comprising vacuum-sealing food, heating it to the desired temperature, and circulating it in a water bath in a sous vide machine. This cooking technique is increasingly common in homes and catering establishments due to its simplicity and affordability. However, manufacturers and chef’s recommendations for low-temperature and long-term sous-vide cooking in media raise food safety concerns, particularly when preparing beef tenderloin. In this study, Salmonella enterica was found to be inactivated by heat and sage essential oil (EO) in beef samples from musculus psoas major that had been sous vide processed. To determine whether heat treatment was likely to increase the sous vide efficiency, S. enterica and sage EO were mixed. After being vacuum-packed and injected with S. enterica, the samples were cooked at 50–65 °C through the sous vide technique for the prescribed time. On days 1, 3, and 6, the amounts of S. enterica, total bacteria, and coliform bacteria were measured in the control and treated groups of beef processed sous vide. Mass spectrometry was used to identify bacterial isolates on different days. On each day that was measured, a higher number of all the microbiota was found in the samples exposed to 50 °C for 5 min. The most frequently isolated microorganisms from both groups of samples were Pseudomonas fragi (17%), Pseudomonas cedrina (8%), and Proteus vulgaris (8%); in the treated group, also S. enterica (21%), Pseudomonas fragi (13%), and Pseudomonas veronii (6%). After the heat treatment of samples at 65 °C for 20 min, the total count of bacteria and coliform bacteria was zero. It has been shown that adding sage essential oil (EO) in combination with sous vide processing technique leads to the stabilization and safety of beef tenderloin.Faculty of Technology; Tomas Bata University in Zlín, TBU, (IGA/FT/2023/007)APVV [SK-BY-RD-19-0014]; Internal Grant Agency of the Faculty of Technology, Tomas Bata University in Zlin [IGA/FT/2023/007
Renewable whey-based hydrogel with polysaccharides and polyvinyl alcohol as a soil amendment for sustainable agricultural application
No full textThis work describes the preparation of a novel biopolymer hydrogel based on acid whey, cellulose derivatives and polyvinyl alcohol (PVA). The hydrogel was prepared and characterized with the aim of producing an environmentally-friendly soil amendment to increase water retention capacity of the soil. The findings showed considerable swelling properties of the hydrogels depending on the PVA content and crosslinking density. The samples with PVA in a concentration 2.5 % and 5 % were more rigid, the gel fraction increased with a subsequently decrease in their swelling capacity. The hydrogels crosslinked with 15 % of citric acid demonstrated a constant swelling ratio (SR) of around 500 % within 10 swelling/drying cycles. The hydrogels crosslinked with 10 % citric acid and supplemented with 1 % of PVA showed SR of 1000–1400 % caused by less crosslinked polymer network and increased pore volume for water uptake. It was found that hydrogel with a higher gel fraction had a stable structure. Supplementing PVA at 5 % extended the period of decomposition of the hydrogel material by almost 60 % in the soil environment and soil humidity was maintained for longer. Applying 2 % of the hydrogel 5PVA to soil increased the water retention capacity by 19 %.Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT, (RP/CPS/2022/002); Ministerstvo Zemědělství, (QK1910392)Ministry of Agriculture of the Czech Republic [QK1910392]; Ministry of Education, Youth and Sports of the Czech Republic [RP/CPS/2022/002
Impact of fintech's development on bank performance: An empirical study from Vietnam
Get PDFIn recent years, fintech has exploded in popularity and importance in the financial industry. Its impacts have spread widely throughout the world, including Vietnam. This study aims to investigate the effect of fintech’s development on bank performance in Vietnam. Based on the unstructured data about fintech on the financial expert websites from Vietnam, the word frequency statistic technique of the text mining approach is applied for measuring fintech’s development under the support of Python-based solutions. The bank-level data of 15 Vietnamese banks for the period from the first quarter of 2019 to the second quarter of 2021 are collected from the quarterly financial statements in the Vietstock organization. Python programming and text mining techniques are used to compile this dataset by gathering information from popular and relevant websites. The generalized least squares method is used for estimating the panel models. The estimation result shows the significant impact of fintech’s development on bank profitability, but the net interest margin does not associate with the fintech variable. Besides, some interesting findings are revealed: The slow banking transformation to adapt to the rise of fintech and the COVID-19 pandemic increased bank profitability. Furthermore, suggestions for the banks and fintech companies are recommended, and the limitations and directions for further research are also proposed
Informal education for boys only? The theme of gender in the work of Jaroslav Foglar
Get PDFThe paper deals with the work of the Czech children's author Jaroslav Foglar from a gender perspective, reflecting on two themes in particular: the absence of heroines; and his understanding of boys' reciprocity and friendship with the adoration of physicality. The impetus for this analysis was data from a questionnaire survey, the aim of which was to determine which aspects of Jaroslav Foglar's work are most appreciated by readers and which they think apply to real life. The quantitative analysis of the data (n=1174) did not reveal any statistically significant differences in the men's and women's responses; however, the qualitative analysis of the open - ended statements is illustrative of the underrepresentation of girls among literary heroes. The diverse ways in which Foglar's work captures friendships between boys allow even today's readers to expand their perceptions of masculinity beyond traditionally defined boundaries
Assessing the impacts of a firm's reputation on the financial performance of SMEs: Evidence from selected literature
No full textFinancial performance has been the beckon of growth of most SMEs worldwide as such there is a growing need to improve small and medium-sized enterprises' (SMEs) reputation to gain more financially and to be highly competitive. For this reason, this study reviewed 25 articles referenced in Web of Science and Scopus journals using a systematic literature review to explain the impacts of reputation on SME firms' financial performance. The author identified differences in theoretical models in the articles and conceptualize them summarily based on the outcome. Articles were selected from 2018 to 2022. The resultant effect of this review asserts that business reputation significantly influences SMEs' financial performance, and it is mediated by leadership. However, profitability reduces if SME leaders concentrate more on investment in reputation as acclaimed by some CEOs. This research will leverage more studies in the field of SME performance and reputational management factors. It will give guidance to future researchers thematically
A measurement exploring the relationship between customer engagement and digital transformation in restaurants
No full textThis research aims to explore and analyze how adopting digital transformation initiatives and leveraging e-marketing techniques can influence various aspects of restaurant operations to improved sales outcomes. This research aims to develop models that explore the connections between based on the principles of the Technology Acceptance Model (TAM) and Customer Relationship Management (CRM). Data was collected through a cross-sectional customer survey, and structural equation modeling was used to analyze the relationships between the variables. The results of hypothesis testing indicate that factors like usefulness and ease of use indirectly influence sales efficiency, which may entail enhancing the overall user experience and increasing the practicality of digital tools. Furthermore, digital transformation and digital marketing directly contribute to sales efficiency, highlighting the importance of developing a robust digital marketing strategy and fostering customer interaction through online channels. These findings highlight the significance of relationship digital transformation and e-marketing's sales impact. Findings promote tech adoption, enhancing operations and customer experience. Research avenues involve exploring transformation's roles, security, and sustainability, cross-industry analysis, long-term effects assessment, and cultural impact on e-marketing. The research results provide valuable insights by demonstrating that the direct contributions of digital transformation and digital marketing to sales efficiency emphasize the significance of crafting strong digital marketing strategies and nurturing customer engagement through online channels. This original contribution highlights the pivotal role of these factors in optimizing restaurant sales effectiveness within the context of digital transformation and e-marketing
The role of auditors in critical infrastructure protection: Case in Czech Republic
Get PDFRecent changes in security and technology environment such as Russia's invasion against Ukraine, the rapid development of technology, internet of things, remote working due to the covid-19 pandemic, has led to an increase in cyber-attacks. The emergence of quantum cryptography could give rise to breaches in quantum security in years to come with national security being affected. Delays or disruptions in the supply chain have led to an increase in the risk of supply chain theft. Personal identity theft is on the increase and as such, the role of auditors in critical infrastructures protection cannot be over- emphasized as this has become a high priority at national and EU level. This review paper examines the role of auditors in protecting critical infrastructures in Czech Republic. It adopted a study carried out by P. Lois et al. (2021), evaluated factors relating to audit and security of information systems. The results of the study concluded that advisory roles of auditors and policy- standards affect the security of information systems
A Kafka-based robot automation testing using genetic algorithm
No full textThe demand for real-time processing of high-volume data streams in contemporary applications is increasing exponentially. Typical application areas include the maintenance of IoT devices, fraud detection systems, electronic trading platforms, etc.… For software development teams (DevOPs), scaling software test automation while managing the test automation process within a reasonable time continues to be a major difficulty. Among the numerous software testing frameworks available, the Data-Driven Testing Framework (DDTF) and the Test-Driven Framework Development are the most popular. Due to the aforementioned constraints, this study utilizes Kafka middleware, a distributed messaging system used in contemporary stream-based applications with reliable and effective stream delivery capacity. Our work primarily uses three tools: Kafka, Robot Framework for Automation Testing (RFAT), and Genetic Algorithm (GA). GA is used to create the list of test cases before the deployment of the Kafka-based implementation of robot automation software testing. We select the first endpoint from the four available endpoints to provide data based on the population size and the given number of generations. The second endpoint (producer) will be called by the RFAT which then forwards the data to the Kafka server in the form of a topic. Finally, the third endpoint consumes the topic-based data from the Kafka server and sends it back to the RFAT where the fourth endpoint will be utilized. To test the average and maximum fitness values, we retrieve generations in accordance with a given threshold value after calling the fourth endpoint