J. Jurišová, V. Danielik, P. Fellner, M. Králik, Tomáš Foltinovič
Abstract Reactivity of various calcium carbonate samples for flue gas desulfurization was tested. Two groups of CaCO3 samples were considered; natural limestone containing calcite phase dominantly and samples prepared by the conversion of gypsum with ammonium and carbon dioxide (precipitated CaCO3) containing different amounts of calcite, aragonite and vaterite. Reactivity of precipitated calcium carbonate depends primarily on the particle size, similarly as in case of industrial samples. The initial reaction rate was comparable with the industrial limestones for samples with the average particle size lower than 15 μm. However, the conversion of laboratory samples was significantly higher after 5 min of the reaction. Phase composition of the precipitated calcium carbonate has a minor but noticeable impact on the reactivity. The presence of vaterite slightly increased the reactivity, which is in accordance with its lower compact structure in comparison with calcite and aragonite. Unexpected effect of the increased content of aragonite, which is the most compact phase in comparison with calcite and vaterite, was observed. If calcium carbonate contains up to approximately 30 % of aragonite the reactivity increases, which can be explained by the SEM pictures showing agglomerate composition with relatively high specific surface. At higher contents of aragonite, the reactivity decreases. All the obtained results proved the suitability of precipitated CaCO3 prepared from flue gas desulfurization gypsum to be recycled in the flue gas desulfurization process.
{"title":"Reactivity of calcium carbonate prepared from flue gas desulfurization gypsum","authors":"J. Jurišová, V. Danielik, P. Fellner, M. Králik, Tomáš Foltinovič","doi":"10.2478/acs-2019-0003","DOIUrl":"https://doi.org/10.2478/acs-2019-0003","url":null,"abstract":"Abstract Reactivity of various calcium carbonate samples for flue gas desulfurization was tested. Two groups of CaCO3 samples were considered; natural limestone containing calcite phase dominantly and samples prepared by the conversion of gypsum with ammonium and carbon dioxide (precipitated CaCO3) containing different amounts of calcite, aragonite and vaterite. Reactivity of precipitated calcium carbonate depends primarily on the particle size, similarly as in case of industrial samples. The initial reaction rate was comparable with the industrial limestones for samples with the average particle size lower than 15 μm. However, the conversion of laboratory samples was significantly higher after 5 min of the reaction. Phase composition of the precipitated calcium carbonate has a minor but noticeable impact on the reactivity. The presence of vaterite slightly increased the reactivity, which is in accordance with its lower compact structure in comparison with calcite and aragonite. Unexpected effect of the increased content of aragonite, which is the most compact phase in comparison with calcite and vaterite, was observed. If calcium carbonate contains up to approximately 30 % of aragonite the reactivity increases, which can be explained by the SEM pictures showing agglomerate composition with relatively high specific surface. At higher contents of aragonite, the reactivity decreases. All the obtained results proved the suitability of precipitated CaCO3 prepared from flue gas desulfurization gypsum to be recycled in the flue gas desulfurization process.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47554187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract At the present time, characterised by worsening environmental conditions, the protection of human organism against irreversible damage is necessary. Protective clothing on base of smart textiles represents the future in human clothing. In this article, the effect of photochromic pigments on spinnability, drawability and properties of pigmented polypropylene (PP) fibres is presented. Mechanical properties (tenacity and elongation at break, Young’s modulus), thermo-mechanical properties and the factor of average orientation of fibres were evaluated and discussed. The obtained results indicate a possibility of fibres preparation with photochromic pigments.
{"title":"Application of photochromic pigment in mass dyed polypropylene fibres intended for intelligent textiles","authors":"Veronika Hrabovská, M. Hricová, A. Ujhelyiová","doi":"10.2478/acs-2019-0012","DOIUrl":"https://doi.org/10.2478/acs-2019-0012","url":null,"abstract":"Abstract At the present time, characterised by worsening environmental conditions, the protection of human organism against irreversible damage is necessary. Protective clothing on base of smart textiles represents the future in human clothing. In this article, the effect of photochromic pigments on spinnability, drawability and properties of pigmented polypropylene (PP) fibres is presented. Mechanical properties (tenacity and elongation at break, Young’s modulus), thermo-mechanical properties and the factor of average orientation of fibres were evaluated and discussed. The obtained results indicate a possibility of fibres preparation with photochromic pigments.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43770571","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Marta Ostrihoňová, Jana Adamíková, T. Molnár, M. Antošová, M. Polakovič
Abstract This work deals with the capture of human recombinant erythropoietin (rhEPO) from a mixture of proteins in a concentrated postcultivation supernatant. Cation-exchange multimodal adsorbent Capto MMC ImpRes was selected as potential chromatographic separation material. Its equilibrium properties were investigated in batch adsorption experiments. The effect of pH in the range of 5.5—7.5 and NaCl concentration in the range of 0—300 mM on the adsorption of rhEPO and contaminant proteins was examined. Optimal conditions found in these equilibrium experiments were applied to rhEPO adsorption in a chromatographic column. Several experiments were carried out at different elution conditions to optimize the rhEPO yield and selectivity.
{"title":"Recombinant human erythropoietin separation using a cation-exchange multimodal adsorbent","authors":"Marta Ostrihoňová, Jana Adamíková, T. Molnár, M. Antošová, M. Polakovič","doi":"10.2478/acs-2019-0015","DOIUrl":"https://doi.org/10.2478/acs-2019-0015","url":null,"abstract":"Abstract This work deals with the capture of human recombinant erythropoietin (rhEPO) from a mixture of proteins in a concentrated postcultivation supernatant. Cation-exchange multimodal adsorbent Capto MMC ImpRes was selected as potential chromatographic separation material. Its equilibrium properties were investigated in batch adsorption experiments. The effect of pH in the range of 5.5—7.5 and NaCl concentration in the range of 0—300 mM on the adsorption of rhEPO and contaminant proteins was examined. Optimal conditions found in these equilibrium experiments were applied to rhEPO adsorption in a chromatographic column. Several experiments were carried out at different elution conditions to optimize the rhEPO yield and selectivity.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44291974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract There is evidence that the transmission of Staphylococcus aureus and methicillin-resistant S. aureus between the community and environmental surfaces still exists. Even the means of this transmission remain uncertain, the public transport system may serve as a potential source of different bacteria, and the contact with contaminated public surfaces may increase the risk for bacterial diseases emergence. This study aimed to investigate S. aureus contamination on Bratislava’s public transport vehicles. Forty samples of hand-touched surfaces were collected during December 2015 and March 2017 by using surface sampling method. S. aureus was detected in all analysed swabs. Simultaneously, antibiotic resistance of S. aureus from swabs was evaluated. Of 40 samples, only 23 % did not contain S. aureus resistant to some of 10 analysed antibiotics. On the other hand, the severe prevalence of highly resistant S. aureus to penicillin, methicillin, ampicillin, and cefoxitin was confirmed. 15 % of isolates displayed resistance to at least three antimicrobial classes. The amount of S. aureus was not significantly influenced by the lines or by the analysed surface (grabs rails or on-board stop buttons). However, there was a statistically significant effect of year period, both between samples from December and March and between samples from the same month but different year. The study confirmed the widespread occurrence of resistant S. aureus in public transport vehicles in Bratislava, Slovakia.
{"title":"Prevalence of Staphylococcus aureus and antibiotic resistant Staphylococcus aureus in public transport in Bratislava, Slovakia","authors":"A. Medveďová, Romana Györiová","doi":"10.2478/acs-2019-0007","DOIUrl":"https://doi.org/10.2478/acs-2019-0007","url":null,"abstract":"Abstract There is evidence that the transmission of Staphylococcus aureus and methicillin-resistant S. aureus between the community and environmental surfaces still exists. Even the means of this transmission remain uncertain, the public transport system may serve as a potential source of different bacteria, and the contact with contaminated public surfaces may increase the risk for bacterial diseases emergence. This study aimed to investigate S. aureus contamination on Bratislava’s public transport vehicles. Forty samples of hand-touched surfaces were collected during December 2015 and March 2017 by using surface sampling method. S. aureus was detected in all analysed swabs. Simultaneously, antibiotic resistance of S. aureus from swabs was evaluated. Of 40 samples, only 23 % did not contain S. aureus resistant to some of 10 analysed antibiotics. On the other hand, the severe prevalence of highly resistant S. aureus to penicillin, methicillin, ampicillin, and cefoxitin was confirmed. 15 % of isolates displayed resistance to at least three antimicrobial classes. The amount of S. aureus was not significantly influenced by the lines or by the analysed surface (grabs rails or on-board stop buttons). However, there was a statistically significant effect of year period, both between samples from December and March and between samples from the same month but different year. The study confirmed the widespread occurrence of resistant S. aureus in public transport vehicles in Bratislava, Slovakia.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2478/acs-2019-0007","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43116739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The aim of the study was to find parameters of electrolytic colouring on tin basis to form uniform black coatings on anodized aluminium. A two steps electrolytic process consisting of aluminium anodization in a sulphuric acid electrolyte and colouring in tin acidic electrolyte was used. Among parameters influencing the colouring process, AC colouring voltage, composition of the counter electrode and agitation of the colouring electrolyte were studied. Spectrocolorimetry was applied to analyse the quality of the colouring. Thickness of the coloured and sealed anodized specimens was also evaluated. Optimal parameters for uniform colouring of anodized specimens were found. Unfortunately, colouring electrolyte on tin basis is susceptible to oxidation which negatively influences the colouring.
{"title":"Electrolytic colouring of anodized aluminium on tin basis","authors":"Barbora Šopová, M. Zemanová","doi":"10.2478/acs-2019-0002","DOIUrl":"https://doi.org/10.2478/acs-2019-0002","url":null,"abstract":"Abstract The aim of the study was to find parameters of electrolytic colouring on tin basis to form uniform black coatings on anodized aluminium. A two steps electrolytic process consisting of aluminium anodization in a sulphuric acid electrolyte and colouring in tin acidic electrolyte was used. Among parameters influencing the colouring process, AC colouring voltage, composition of the counter electrode and agitation of the colouring electrolyte were studied. Spectrocolorimetry was applied to analyse the quality of the colouring. Thickness of the coloured and sealed anodized specimens was also evaluated. Optimal parameters for uniform colouring of anodized specimens were found. Unfortunately, colouring electrolyte on tin basis is susceptible to oxidation which negatively influences the colouring.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46723633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract This work was focused on the characterization of novel isolate of Trichoderma atroviride O1, found in the forest around the village of Zázrivá (the Northern Slovakia, region Orava). The isolate was identified by sequencing its internal transcribed spacer (ITS) region of rDNA. T. atroviride O1 stimulated the development of lateral roots of model plant Lepidium sativum. Simultaneously, the isolate has proved its high mycoparasitic potential as it displayed the ability to attack colonies of phytopathogenic fungi (Alternaria alternata, Fusarium culmorum, Botrytis cinerea). This isolate produced secondary metabolites, which were isolated and tested for the antimicrobial activity against gram-positive bacteria Staphylococcus epidermidis and Staphylococcus aureus. The growth of these bacteria was suppressed to 10 % and 40 %, respectively. The suppression of the growth of two Candida species was also strong (10 % growth). However, growth parameters of three phytopathogenic fungi (Alternaria alternata, Botrytis cinerea and Fusarium culmorum) were less affected (75 % growth in comparison with the control). Attempts were made to characterize secondary metabolites isolated from T. atroviride O1. Known peptaibols, 20—21 amino acid long, but also shorter peptides, were detected by MALDI-TOF mass spectrometry. Thus, this study demonstrates the plant growth promotion, strong mycoparasitic potential and antimicrobial activity of the isolate T. atroviride O1, which could be in part ascribed to the production of secondary metabolites. This isolate does have a potential in the biocontrol in eco-farming. Further study, particularly, the identification of produced secondary metabolites, is needed.
{"title":"Trichoderma atroviride: an isolate from forest environment with secondary metabolites with high antimicrobial potential","authors":"J. Víglaš, P. Olejníková","doi":"10.2478/acs-2019-0008","DOIUrl":"https://doi.org/10.2478/acs-2019-0008","url":null,"abstract":"Abstract This work was focused on the characterization of novel isolate of Trichoderma atroviride O1, found in the forest around the village of Zázrivá (the Northern Slovakia, region Orava). The isolate was identified by sequencing its internal transcribed spacer (ITS) region of rDNA. T. atroviride O1 stimulated the development of lateral roots of model plant Lepidium sativum. Simultaneously, the isolate has proved its high mycoparasitic potential as it displayed the ability to attack colonies of phytopathogenic fungi (Alternaria alternata, Fusarium culmorum, Botrytis cinerea). This isolate produced secondary metabolites, which were isolated and tested for the antimicrobial activity against gram-positive bacteria Staphylococcus epidermidis and Staphylococcus aureus. The growth of these bacteria was suppressed to 10 % and 40 %, respectively. The suppression of the growth of two Candida species was also strong (10 % growth). However, growth parameters of three phytopathogenic fungi (Alternaria alternata, Botrytis cinerea and Fusarium culmorum) were less affected (75 % growth in comparison with the control). Attempts were made to characterize secondary metabolites isolated from T. atroviride O1. Known peptaibols, 20—21 amino acid long, but also shorter peptides, were detected by MALDI-TOF mass spectrometry. Thus, this study demonstrates the plant growth promotion, strong mycoparasitic potential and antimicrobial activity of the isolate T. atroviride O1, which could be in part ascribed to the production of secondary metabolites. This isolate does have a potential in the biocontrol in eco-farming. Further study, particularly, the identification of produced secondary metabolites, is needed.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46741791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kristína Lépesová, Monika Krahulcová, T. Mackuľak, L. Bírošová
Abstract Subinhibitory concentrations of antibiotics and biocides in wastewaters and sewage sludge have a great impact on the development of antibiotic resistance and its spread among bacteria. The aim of this work was to determine the occurrence of coliform bacteria and enterococci resistant to biocide triclosan in samples of sewage sludge. Subsequently, isolated strains of coliform bacteria were identified and characterized in terms of their antibiotic susceptibility and ability to form a biofilm. Occurrence of the studied bacteria was monitored in three samples of stabilized sludge from three different wastewater treatment plants (Vrakuňa, Petržalka, and Senec). The number of triclosan-resistant coliforms was the highest in the sludge sample from the wastewater treatment plant in Senec and the lowest in the sludge sample from the wastewater treatment plant in Petržalka. Triclosan-resistant Enterococcus spp. were not found in any sample of stabilized sludge. Most isolates were identified as Citrobacter freundii and Serratia spp. Triclosan-resistant isolates showed also resistance to antibiotics and the majority of them were strong biofilm producers.
{"title":"Sewage sludge as a source of triclosan-resistant bacteria","authors":"Kristína Lépesová, Monika Krahulcová, T. Mackuľak, L. Bírošová","doi":"10.2478/acs-2019-0006","DOIUrl":"https://doi.org/10.2478/acs-2019-0006","url":null,"abstract":"Abstract Subinhibitory concentrations of antibiotics and biocides in wastewaters and sewage sludge have a great impact on the development of antibiotic resistance and its spread among bacteria. The aim of this work was to determine the occurrence of coliform bacteria and enterococci resistant to biocide triclosan in samples of sewage sludge. Subsequently, isolated strains of coliform bacteria were identified and characterized in terms of their antibiotic susceptibility and ability to form a biofilm. Occurrence of the studied bacteria was monitored in three samples of stabilized sludge from three different wastewater treatment plants (Vrakuňa, Petržalka, and Senec). The number of triclosan-resistant coliforms was the highest in the sludge sample from the wastewater treatment plant in Senec and the lowest in the sludge sample from the wastewater treatment plant in Petržalka. Triclosan-resistant Enterococcus spp. were not found in any sample of stabilized sludge. Most isolates were identified as Citrobacter freundii and Serratia spp. Triclosan-resistant isolates showed also resistance to antibiotics and the majority of them were strong biofilm producers.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42838674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Miroslav Variny, Patrik Furda, N. Kováč, O. Mierka
Abstract Propane-propylene mixture splitting by industrial conventional rectification incorporating a heat pump for energy intensity decrease was modeled in the Matlab environment. The constructed model was verified by comparing its results with operational data of a real C3 fraction splitting unit. As documented, increased product quality can be obtained at zero additional costs due to specific features of the system design. Process capacity and product purity limitations have to be considered in future C3 fraction production increase plans. Further compressor and its driving unit design features have to be incorporated in the calculation model to reliably assess the C3 fraction processing costs and provide a reliable tool for process operation optimization.
{"title":"Analysis of C3 fraction splitting system performance by mathematical modeling in MATLAB environment","authors":"Miroslav Variny, Patrik Furda, N. Kováč, O. Mierka","doi":"10.2478/acs-2019-0018","DOIUrl":"https://doi.org/10.2478/acs-2019-0018","url":null,"abstract":"Abstract Propane-propylene mixture splitting by industrial conventional rectification incorporating a heat pump for energy intensity decrease was modeled in the Matlab environment. The constructed model was verified by comparing its results with operational data of a real C3 fraction splitting unit. As documented, increased product quality can be obtained at zero additional costs due to specific features of the system design. Process capacity and product purity limitations have to be considered in future C3 fraction production increase plans. Further compressor and its driving unit design features have to be incorporated in the calculation model to reliably assess the C3 fraction processing costs and provide a reliable tool for process operation optimization.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47305713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. Urminská, J. Derco, Ronald Zakhar, Adriana Korpicsová
Abstract Natural or synthetic zeolites have unique physical, chemical and structural properties that predetermine their use in many processes, including wastewater treatment. This study presents the results of our preliminary research in the field of nitrogen and phosphorus removal using adsorption and adsorptive ozonation with natural and modified zeolites. Iron-modified zeolite was the most efficient for the removal of ammonium nitrogen by adsorption. Phosphorus removal efficiency using adsorption was relatively low and natural zeolite was not suitable for the phosphorus removal at all. Ozone had no significant impact on the removal efficiency. Regeneration of loaded zeolites with ozone has also been studied. This method was partly efficient but it needs be further examined.
{"title":"Use of zeolites for macronutrients removal from wastewater","authors":"B. Urminská, J. Derco, Ronald Zakhar, Adriana Korpicsová","doi":"10.2478/acs-2019-0021","DOIUrl":"https://doi.org/10.2478/acs-2019-0021","url":null,"abstract":"Abstract Natural or synthetic zeolites have unique physical, chemical and structural properties that predetermine their use in many processes, including wastewater treatment. This study presents the results of our preliminary research in the field of nitrogen and phosphorus removal using adsorption and adsorptive ozonation with natural and modified zeolites. Iron-modified zeolite was the most efficient for the removal of ammonium nitrogen by adsorption. Phosphorus removal efficiency using adsorption was relatively low and natural zeolite was not suitable for the phosphorus removal at all. Ozone had no significant impact on the removal efficiency. Regeneration of loaded zeolites with ozone has also been studied. This method was partly efficient but it needs be further examined.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2478/acs-2019-0021","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44915732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Kruželák, Andrea Kvasničáková, R. Dosoudil, I. Hudeč
Abstract Two types of composites based on natural rubber (NR) and strontium ferrite were tested in this study. Composites of the first type were prepared by incorporation of strontium ferrite in the concentration range ranging from 0 to 100 phr (parts per hundred rubber) into pure NR based rubber matrix, while with those of the second type, strontium ferrite was dosed in the same concentration level into NR based rubber batch with constant amount of carbon black — 25 phr. For rubber matrices cross-linking, a standard sulfur based curing system was used. This work is focused on the effect of magnetic filler content on physico-mechanical, magnetic and thermo-physical properties of composite materials. Subsequently, the cross-link density and the structure of the formed sulfidic cross-links were examined. The results showed that the cross-link density of both types of composites increased with the increasing content of magnetic filler, while the structure of the sulfidic cross-links was almost not influenced by the amount of strontium ferrite. Tensile strength of rubber composites with pure rubber matrix was slightly improved by the incorporation of ferrite, while in case of composites based on a carbon black batch, the incorporation of magnetic filler resulted in the decrease of this characteristic. The presence of magnetic filler in both types of composites leads to a significant increase of the remanent magnetic induction.
{"title":"Magnetic composites based on NR and strontium ferrite","authors":"J. Kruželák, Andrea Kvasničáková, R. Dosoudil, I. Hudeč","doi":"10.2478/acs-2019-0010","DOIUrl":"https://doi.org/10.2478/acs-2019-0010","url":null,"abstract":"Abstract Two types of composites based on natural rubber (NR) and strontium ferrite were tested in this study. Composites of the first type were prepared by incorporation of strontium ferrite in the concentration range ranging from 0 to 100 phr (parts per hundred rubber) into pure NR based rubber matrix, while with those of the second type, strontium ferrite was dosed in the same concentration level into NR based rubber batch with constant amount of carbon black — 25 phr. For rubber matrices cross-linking, a standard sulfur based curing system was used. This work is focused on the effect of magnetic filler content on physico-mechanical, magnetic and thermo-physical properties of composite materials. Subsequently, the cross-link density and the structure of the formed sulfidic cross-links were examined. The results showed that the cross-link density of both types of composites increased with the increasing content of magnetic filler, while the structure of the sulfidic cross-links was almost not influenced by the amount of strontium ferrite. Tensile strength of rubber composites with pure rubber matrix was slightly improved by the incorporation of ferrite, while in case of composites based on a carbon black batch, the incorporation of magnetic filler resulted in the decrease of this characteristic. The presence of magnetic filler in both types of composites leads to a significant increase of the remanent magnetic induction.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46289012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：