Tomas Bata University in Zlín
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Bimetallic MoFe phosphide catalysts for the hydrogen evolution reaction
No full textIn this work, highly efficient and stable (bi)metallic phosphides were prepared by a facile, flexible, and controllable sol-gel method followed by sintering. This novel approach allowed to avoid complicated and dangerous phosporization using, e.g. red phosphorus. The doping of the MoP catalysts with Fe was used to further boost their catalytic performance. Monometallic MoP and Mo3P, as well as bimetallic MoFeP were tested in both acidic and alkaline environments and showed remarkable results. The incorporation of Fe enabled the creation of a scalable and cost-effective catalyst for the hydrogen evolution reaction due to the synergy between Fe and Mo in the bimetallic phosphides. Using MoFeP for catalysing the hydrogen evolution reaction, overpotentials of only -132 mV (in an acidic medium) and -142 mV (in an alkaline medium) were needed to reach current density of -10 mA.cm−2, indicating the possibility of use this catalyst in a large pH range. Its high catalytic activity was maintained even at current density of -100 mA.cm−2 as documented by overpotentials of -202 mV and -246 mV in acid and alkaline environment, respectively. This, along with excellent stability and durability confirms its promising potential for incorporation into industrially relevant applications. The experimental data were confirmed by computational (DFT) results, showcasing that incorporation of Fe caused an increase in the number of active sites with Gibbs adsorption energy close to zero.Vedecká Grantová Agentúra MŠVVaŠ SR a SAV, VEGA, (2/0027/23); European Regional Development Fund, ERDF, (CZ.02.1.01/0.0/0.0/16_025/ 0007414); Scientific Grant Agency of the Ministry of Education, Science , Research and Sport of the Slovak Republic, (VEGA 2/0027/23); Ministerstvo školstva, vedy, výskumu a športu Slovenskej republiky, (VEGA 1/0095/21); Agentúra na Podporu Výskumu a Vývoja, APVV, (APVV-20-0299, APVV-20-0576)Scientific Grant Agency of the Ministry of Education, Science, Research and Sport of the Slovak Re-public [VEGA 1/0095/21, VEGA 2/0027/23]; Slovak Research and Development Agency [APVV-20-0299, APVV-20-0576]; European Regional Development Fund Project 'Fuel Cells with Low Platinum Content' [CZ.02.1.01/0.0/0.0/16_025/0007414
Sustainable valorization of slaughterhouse waste through anaerobic digestion: A circular economy perspective
No full textSlaughterhouse waste (SHW) poses significant environmental challenges due to its complex composition. In response, a novel review exploration of anaerobic digestion (AD) as a means of valorising SHW within the context of the circular economy (CE) is presented. The physicochemical properties of individual SHW, representing key parameters for the correct management of the AD process, are scrutinized. These parameters are further connected with identifying suitable pretreatment methods to enhance biogas production. Subsequently, the review examines the diverse technologies employed in the AD of SHW, considering the complexities of monoor co-digestion. Various AD systems are evaluated for their effectiveness in harnessing the substantial biogas production potential from SHW, encompassing key parameters, reactor configurations, and operational conditions that influence the AD process. Moreover, the review interestingly extends its scope to the recovery and management of digestate, the by-product of AD. Along with the digestate composition, strategies for various utilization of this by-product are discussed. This investigation thus underscores, within the principles of the CE, the dual sustainable benefits of SHW processing via AD in biogas production and utilization of the resultant nutrient-rich digestate in various sectors.Internal projects of the Tomas Bata University in Zlin [RVO/CEBIA/2021/003]Univerzita Tomáše Bati ve Zlíně, UTB, (RVO/CEBIA/2021/003); Univerzita Tomáše Bati ve Zlíně, UT
Core-shell inorganic/organic composites composed of polypyrrole nanoglobules or nanotubes deposited on MnZn ferrite microparticles: Electrical and magnetic properties
Full text linkCore-shell inorganic/organic composites have often been applied as fillers in electromagnetic interference shielding. Those composed of conducting polymers and ferrites are of particular interests with respect to their electrical and magnetic properties. Pyrrole was oxidized in aqueous medium in the presence of manganese-zinc ferrite microparticles with ammonium peroxydisulfate or iron(III) chloride to yield polypyrrole-coated, core-shell microstructures. The effect of methyl orange dye on the conversion of globular polypyrrole to nanotubes has been demonstrated by electron microscopy when iron(III) chloride was used as an oxidant. The formation of polypyrrole was proved by FTIR spectroscopy. The completeness of ferrite coating was confirmed by Raman spectroscopy. The resistivity of composite powders was determined by four-point van der Pauw method as a function of pressure applied up to 10 MPa. The conductivity of composite powders was determined by a polypyrrole matrix and only moderately decreased with increasing content of ferrite. The highest conductivity of composites, 13-25 S cm-1, was achieved after the deposition of polypyrrole nanotubes. Magnetic properties of composites have not been affected by the polypyrrole moiety, and the magnetization of composites was proportional to the ferrite content.Ministry of Education, Youth and Sports of the Czech Republic; Czech Science Foundation [22-25734S]; [INTER-EXCELLENCE II LUAUS24032]; [RP/CPS/2024-28/005
Compact 3D-printed unit for separation of simple gas mixtures combined with chemiresistive sensors
Full text linkInexpensive chemiresistive sensors are often insufficiently selective as they are sensitive to multiple components of the gas mixture at the same time. One solution would be to insert a device in front of the sensor that separates the measured gas mixture and possibly isolates the unwanted components. This study focused on the fabrication and characterization of a compact unit, which was fabricated by 3D printing, for the separation and detection of simple gas mixtures. The capillary, the basic part of the compact unit, was 4.689 m long and had a diameter of 0.7 mm. The compact unit also contained a mixing chamber on the inlet side and a measuring chamber with a MiCS-6814 sensor on the outlet side. Mixtures of ethanol and water at different concentrations were chosen for characterization. The measured calibration curve was found to have a reliability of R2 = 0.9941. The study further addressed the elements of environmental friendliness of the materials used and their sustainability.Internal Grant Agency of Tomas Bata University in Zlin [IGA/FT/2024/006, RVO/CEBIA/2024/001]; Brno University of Technology in Brno [FEKT-S-23-8162]; Ministry of Education, Youth and Sports of the Czech Republic-DKRVO [RP/CPS/2022/007
Impact of information environment on investment efficiency among Vietnamese listed firms
No full textThis paper investigates the impact of the information environment on investment efficiency among listed firms in Vietnam. This purpose is accomplished by constructing a model according to Biddle et al. (2009) and regressing this model with a sample of 531 Vietnamese non-financial listed firms. The results show that both internal and external information environments improve investment efficiency. The positive impact of the information environment on investment efficiency is materialized by reducing over-and under-investment. As measured by financial reporting quality, the internal information environment enhances investment efficiency by providing timely access to valuable financial information and improving internal transparency. The external information environment proxied by the information transparency index benefits investment efficiency by mitigating information asymmetry, allowing firms to disclose relevant information and incorporate new developments into their business plans. These findings highlight the importance of fostering effective information environments to optimize investment decisions
Fine carbonyl iron particles grafted with poly(2-isopropenyl-2-oxazoline): A potential embolization agent for cancer therapy
No full textDespite the significant success of clinical trials on cancer patients using the therapy with carbonyl iron (CI) particles, this topic laid dormant for over two decades. In this context, we developed a CI particle-based embolization agent via polymer surface engineering and tested its biocompatibility and behavior in contact with human blood. The finest grade of the CI particles was controllably grafted with poly(2-isopropenyl-2-oxazoline) (PiPOx) using surface-initiated atom transfer radical polymerization (ATRP) to achieve a system combining the properties of suitable size, high magnetization, and advantages at the cellular level connected to the presence of PiPOx. The cell viability of 3T3 fibroblasts and P388.D1 macrophages was investigated after treatment with particle extracts and was found to be concentration-dependent but generally demonstrated no or mild cytotoxicity. The PiPOx-grafted particles showed negligible effect on the breakdown of human erythrocytes and significantly improved hydrophilic-hemophilic properties when compared to bare CI. The magnetorheological (MR) activity of the particles dispersed in human blood was studied in vitro under shear mode conditions showing slightly decreased shear stresses but improved sedimentation stability. Moreover, the effect of PiPOx molecular weight on the studied parameters was monitored across the whole range of tests. The study demonstrates the potential of prepared core-shell structures in biomedical and related fields of application.plasma surface engineering; Tomas Bata Regional Hospital in Zlin; MUDr; Department of Haematology, Christian Medical College, Vellore; Tomas Bata University in Zlín, TBU; Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT; Vedecká Grantová Agentúra MŠVVaŠ SR a SAV, VEGA, (2/0137/23, RP/CPS/2022/001); Slovenian Research Agency Core Funding, (P2-0082)Ministry of Education, Youth and Sports of the Czech Republic [RP/CPS/2022/007, RP/CPS/2024-28/007, RP/CPS/2022/001]; VEGA [2/0137/23]; Slovenian Research Agency Core Funding [P2-0082
Anelosimus eximius bioinspired ZnO nano cobwebs for environmental remediation of drugs and endocrine disruptors from water
Full text linkThe pollution of wastewater with pharmaceuticals and endocrine-disrupting chemicals (EDCs) in populated areas poses a growing threat to humans and ecosystems. To address this serious problem, various one-dimensional (1D) hierarchical ZnO-based nanostructures inspired by Anelosimus eximius cobwebs were developed and successfully grown on a glass substrate through simple hydrothermal synthesis. The nanorods (nr) obtained during primary growth were chemically etched with KOH (ZnOnr-KOH), followed by the secondary growth of nano cobweb-like (ncw) structures using polyethyleneimine (ZnOnr/ncw). These structures were further decorated by the photoreduction of Ag nanoparticles (ZnOnr/ncw/Ag). The feasibility of ZnO-based 1D nanostructures to remove pollutants was demonstrated by degrading commonly prescribed pharmaceutical drugs (diclofenac and carbamazepine) in a miniature cuvette reactor. The photocatalytic activities for drug degradation generally decreased in the order ZnOnr/ncw/Ag > ZnOnr/ncw > ZnOnr-KOH. Additionally, the suitability of the samples for scaling up and practical application was demonstrated by photocatalytic degradation of the hormone estriol (E3) in a flow-through photoreactor. The photocatalytic degradation efficiency of E3 followed the same trend observed for drug degradation, with the complete elimination of the endocrine disruptor achieved by the best-performing ZnOnr/ncw/Ag within 4 h, due to optimized charge transfer and separation at the heterostructure interface.Intelligence & Talent for the Zlín Region; Changzhou Institute of Technology, CIT; European Union´s Horizon 2020 research and innovation program; Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT; TBU in Zlin, (IGA/CPS/2023/006); INTER-EXCELLENCE, (LTT20010); Horizon 2020, (739566); Horizon 2020; DKRVO, (RP/CPS/2024-28/007); Agentúra na Podporu Výskumu a Vývoja, APVV, (VEGA 1/0844/21); Agentúra na Podporu Výskumu a Vývoja, APV
On the way to net zero emissions. Can environmental tax be the game changer? The Vise Grad group evidence
Full text linkToday, protecting the environment is a top issue for global policy. In essence, the literature has identified several macroeconomic problems as factors in environmental deterioration. The purpose of the investigation was to explore environmental deterioration (EVD) and energy consumption (ENC) by Vise grad regions. Environmental taxes (ENTX) and carbon taxes have been proving to be a significant factor in carbon mitigation. The analysis was carried out for the period 1994-2021, employing the fully modified ordinary least square (FMOLS) and dynamic ordinary least square (DOLS). The empirical evaluation indicates that ENC had a positive while ENTX had a negative nexus with EVD for the Vise grad nations. Similarly, the moderating role of ENTX*ENC – EVD exhibited an inverse affiliation. In the long run, the dependence on non-renewable energy appreciates EVD. However, effective policy implementation of ENTX will lead to quality of the environment. The empirical results have shown that ENTX can be employed to control the demand and utilization of coal, gas, and nuclear in the Vise grad regions. This research offers policymakers and government organizations in these areas a reference point for their investments in more eco-friendly technology, human capital, urbanization, trade openness, and appropriate environmental levies to demonstrate the quality of the environment.Scientific Grant Agency of the Ministry of Education, Research, Development and Youth of the Slovak Republic; Vedecká Grantová Agentúra MŠVVaŠ SR a SAV, VEGA; European Commission, EC; Ministry of Education, Research, Development and Youth of the Slovak Republic; Slovenská Akadémia Vied, SAV, (1/0590/22); Slovenská Akadémia Vied, SA
Analysis of the ecological footprint of mining machines in the phase of material extraction and processing in LCA
Full text linkSustainability in the mining industry continues to be a challenge. Although there is research in this area, there are still no solutions supporting the assessment of environmental impact in this sector. Therefore, it is important to look for and conduct various types of analyses that will be useful in this area. Therefore, the objective of the research was to analyse the ecological footprint of mining machines in the first phase of the LCA life cycle (obtaining and extracting materials). The analysis was based on the example of a hydraulic actuator, which is considered crucial to control machines in the mining industry. The ecological footprint burdens analysed included direct and indirect land take, sequestration of carbon dioxide (CO2) emissions, and the use of nuclear energy. Life cycle assessment was carried out using the OpenLCA software with the ecoinvent v3.10 database. It has been shown that the largest amount of emissions occurs during off-site treatment of nonsulphide waste, cogeneration of heat and energy (hard coal), production of ferrochrome, high carbon, 68% Cr, and heat production in an industrial furnace using hard coal. It is proposed to carry out improvement activities that will first contribute to reducing the main environmental burdens. Then, it will be possible to significantly reduce the negative environmental impact of the hydraulic actuator's extraction and processing of materials. The results from the analysis may be useful not only for products from the mining industry but also in other areas of activity using this type of machine
Using LLM for automatic evolvement of metaheuristics from swarm algorithm SOMA
No full textThis study investigates the use of the GPT-4 Turbo, a large language model, to enhance the Self-Organizing Migrating Algorithm (SOMA), specifically its All to All variant (SOMA-ATA). Utilizing the model's extensive context capacity for iterative prompting without feedback, we sought to autonomously generate superior algorithmic versions. Contrary to our initial hypothesis, the improvements did not progress linearly. Nevertheless, one iteration stood out significantly, consistently outperforming the baseline across various pairwise comparisons and showing a robust performance profile. This iteration's structure deviated substantially from traditional SOMA principles, underscoring the potential of large language models to create distinctive and effective algorithmic strategies. The results affirm the methodology's ability to produce high-performing algorithms without expert intervention, setting the stage for future research to integrate feedback mechanisms and conduct detailed code analyses to understand further the modifications made by the Large Language Models.Fakulta aplikované informatiky, Univerzita Tomáše Bati ve Zlíně, FAI; Ministerstwo Edukacji i Nauki, MNiSW; Tomas Bata University in Zlín, TBU, (IGA/CebiaTech/2023/004); Tomas Bata University in Zlín, TBU; Grantová Agentura České Republiky, GAČR, (GF21-45465L); Grantová Agentura České Republiky, GAČR; Narodowe Centrum Nauki, NCN, (2020/39/I/ST7/02285); Narodowe Centrum Nauki, NC