Petra Szabová, Michaela Plekancová, Nikolas Gróf, I. Bodík
Abstract Pharmaceuticals are one of the most used compounds present in various environmental compartments. Due to their high consumption and possible unhealthy effect on ecosystems, pharmaceuticals have been identified as “emerging organic contaminants”. Since these compounds have medium to high polarity, they end up in the water compartment after being used. This work deals with the sorption of three pharmaceutical substances from the therapeutic group of antibiotics. Specifically we have focused on Azithromycin, Clarithromycin and Erythromycin. Three fractions of the natural Slovak zeolites (200 μm, 0.5—1 mm and 1.5—2 mm) were used as the sorption medium. Experimental results have proven very effective sorption of antibiotics by zeolites. Azithromycin removal of over 99 % for all three zeolite fractions from wastewater treatment plant Stupava and wastewater treatment plant Devínska Nová Ves was achieved. Clarithromycin removal of 79 % for fraction 1—2.5 mm, 87.3 % for fraction 0.5—1 mm and of 99.8 % for fraction 200 μm from the effluent of wastewater treatment plant Stupava was observed. Erythromycin removal of 31.3 % for fraction 1—2.5 mm, 66.9 % for fraction 0.5—1mm and of 94.7 % for fraction 200 μm from effluent of wastewater treatment plant Stupava was measured. More than 95 % of Clarithromycin and Erythromycin were eliminated from the effluent of wastewater treatment plant Devínska Nová Ves. The highest elimination percentage was observed for the smallest zeolite fraction due to the highest specific surface area.
{"title":"Slovak natural zeolites as a suitable medium for antibiotics elimination from wastewater","authors":"Petra Szabová, Michaela Plekancová, Nikolas Gróf, I. Bodík","doi":"10.2478/acs-2019-0022","DOIUrl":"https://doi.org/10.2478/acs-2019-0022","url":null,"abstract":"Abstract Pharmaceuticals are one of the most used compounds present in various environmental compartments. Due to their high consumption and possible unhealthy effect on ecosystems, pharmaceuticals have been identified as “emerging organic contaminants”. Since these compounds have medium to high polarity, they end up in the water compartment after being used. This work deals with the sorption of three pharmaceutical substances from the therapeutic group of antibiotics. Specifically we have focused on Azithromycin, Clarithromycin and Erythromycin. Three fractions of the natural Slovak zeolites (200 μm, 0.5—1 mm and 1.5—2 mm) were used as the sorption medium. Experimental results have proven very effective sorption of antibiotics by zeolites. Azithromycin removal of over 99 % for all three zeolite fractions from wastewater treatment plant Stupava and wastewater treatment plant Devínska Nová Ves was achieved. Clarithromycin removal of 79 % for fraction 1—2.5 mm, 87.3 % for fraction 0.5—1 mm and of 99.8 % for fraction 200 μm from the effluent of wastewater treatment plant Stupava was observed. Erythromycin removal of 31.3 % for fraction 1—2.5 mm, 66.9 % for fraction 0.5—1mm and of 94.7 % for fraction 200 μm from effluent of wastewater treatment plant Stupava was measured. More than 95 % of Clarithromycin and Erythromycin were eliminated from the effluent of wastewater treatment plant Devínska Nová Ves. The highest elimination percentage was observed for the smallest zeolite fraction due to the highest specific surface area.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":"12 1","pages":"163 - 167"},"PeriodicalIF":0.8,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42876986","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 Theoretical prediction ability of M06-2X functional was tested for thermodynamics of phenol, 15 para and 15 meta phenol derivatives. Calculations were done for gas phase as well as for polar and nonpolar solvents. Although predicted values might be shifted from the experimental ones in the framework of the employed DFT functional and basis set, the calculated and experimental data sets correlate well together. Very good linearity was found especially for the correlation of experimental and theoretical proton affinities. Hammett type correlations between the environments considered were compared. The phenolic C—O bond length was also tested as an alternative substituent effect descriptor while the type and position of the functional group on the aromatic ring have a direct effect on the phenolic bond.
{"title":"Antioxidant action of phenols: Revisiting theoretical calculations of their thermodynamics","authors":"Monika Biela, Bernadeta Pelikánová, M. Michalík","doi":"10.2478/acs-2019-0029","DOIUrl":"https://doi.org/10.2478/acs-2019-0029","url":null,"abstract":"Abstract Theoretical prediction ability of M06-2X functional was tested for thermodynamics of phenol, 15 para and 15 meta phenol derivatives. Calculations were done for gas phase as well as for polar and nonpolar solvents. Although predicted values might be shifted from the experimental ones in the framework of the employed DFT functional and basis set, the calculated and experimental data sets correlate well together. Very good linearity was found especially for the correlation of experimental and theoretical proton affinities. Hammett type correlations between the environments considered were compared. The phenolic C—O bond length was also tested as an alternative substituent effect descriptor while the type and position of the functional group on the aromatic ring have a direct effect on the phenolic bond.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":"12 1","pages":"212 - 217"},"PeriodicalIF":0.8,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44549295","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 Pretreatment of particles obtained from lignocellulosic materials by steam explosion with indirect control by enzymatic hydrolysis has been studied. The dendromass pretreatment model has been applied for recycled fibreboard and particle board based on softwood. Their structure and chemical composition partly predetermine these lignocellulosic materials consisting of a mixture of spruce and fir particles also for bioethanol production. Optimum steam explosion temperature of 205 °C was determined based on the concentration of total monosaccharides — glucose, xylose and arabinose, among all experimentally prepared hydrolysates. This corresponds to basic conditions for fine disintegration of biomass to lignocellulosic structure with good holocellulose accessibility. Particles obtained from fibreboard and particle board primarily consisting of softwood without steam explosion pretreatment provide relatively low cellulose accessibility for commercial enzymes activity while monosaccharides concentration is partly reduced because of torrefaction at high temperatures. The concentration of monosaccharides in hydrolysates was determined for original sample and each steam explosion temperature. Based on the steam explosion conditions, the effect of severity factors was investigated to find optimum pretreatment conditions to increase accessibility of softwood cellulose and hemicelluloses. The identified optimum severity factor RO = 4.09 matches the optimum steam explosion temperature of 205 °C and the residence time of 10 minutes.
{"title":"Steam explosion of wood particles from fibreboard and particle board with indirect control by enzymatic hydrolysis","authors":"A. Pažitný","doi":"10.2478/acs-2019-0026","DOIUrl":"https://doi.org/10.2478/acs-2019-0026","url":null,"abstract":"Abstract Pretreatment of particles obtained from lignocellulosic materials by steam explosion with indirect control by enzymatic hydrolysis has been studied. The dendromass pretreatment model has been applied for recycled fibreboard and particle board based on softwood. Their structure and chemical composition partly predetermine these lignocellulosic materials consisting of a mixture of spruce and fir particles also for bioethanol production. Optimum steam explosion temperature of 205 °C was determined based on the concentration of total monosaccharides — glucose, xylose and arabinose, among all experimentally prepared hydrolysates. This corresponds to basic conditions for fine disintegration of biomass to lignocellulosic structure with good holocellulose accessibility. Particles obtained from fibreboard and particle board primarily consisting of softwood without steam explosion pretreatment provide relatively low cellulose accessibility for commercial enzymes activity while monosaccharides concentration is partly reduced because of torrefaction at high temperatures. The concentration of monosaccharides in hydrolysates was determined for original sample and each steam explosion temperature. Based on the steam explosion conditions, the effect of severity factors was investigated to find optimum pretreatment conditions to increase accessibility of softwood cellulose and hemicelluloses. The identified optimum severity factor RO = 4.09 matches the optimum steam explosion temperature of 205 °C and the residence time of 10 minutes.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":"12 1","pages":"185 - 191"},"PeriodicalIF":0.8,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41576032","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}
D. Cagardová, M. Michalík, E. Klein, V. Lukeš, Z. Marković
Abstract Theoretical study of phenol, thiophenol, benzeneselenol, aniline and their para-amino and paranitro derivatives is presented. Neutral molecules, their deprotonated forms, neutral radicals, and radical cations were studied using three Density Functional Theory (DFT) functionals as well as combined DFT and ab initio G4 method in order to calculate the N—H, O—H, S—H, and Se—H bond dissociation enthalpies (BDE), proton affinities of corresponding anions (PA) and ionization potentials (IP) of studied compounds. These quantities represent fundamental reaction enthalpies related to the radical scavenging action of primary antioxidants. Calculated values were compared with available experimental data to assess applicability of the computational approaches employed. M06-2X/6-311++G(d,p) and G4 methods showed the best agreement with the available experimental gas-phase reaction enthalpies.
{"title":"DFT and ab initio calculations of ionization potentials, proton affinities and bond dissociation enthalpies of aromatic compounds","authors":"D. Cagardová, M. Michalík, E. Klein, V. Lukeš, Z. Marković","doi":"10.2478/acs-2019-0032","DOIUrl":"https://doi.org/10.2478/acs-2019-0032","url":null,"abstract":"Abstract Theoretical study of phenol, thiophenol, benzeneselenol, aniline and their para-amino and paranitro derivatives is presented. Neutral molecules, their deprotonated forms, neutral radicals, and radical cations were studied using three Density Functional Theory (DFT) functionals as well as combined DFT and ab initio G4 method in order to calculate the N—H, O—H, S—H, and Se—H bond dissociation enthalpies (BDE), proton affinities of corresponding anions (PA) and ionization potentials (IP) of studied compounds. These quantities represent fundamental reaction enthalpies related to the radical scavenging action of primary antioxidants. Calculated values were compared with available experimental data to assess applicability of the computational approaches employed. M06-2X/6-311++G(d,p) and G4 methods showed the best agreement with the available experimental gas-phase reaction enthalpies.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":"12 1","pages":"225 - 240"},"PeriodicalIF":0.8,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46994763","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 growth of Staphylococcus aureus 2064 isolate in model nutrient broth was studied as affected by temperature and water activity using principles and models of predictive microbiology. Specific rates resulting from growth curves fitted by the Baranyi model were modelled by the secondary Ratkowsky model for suboptimal temperature range (RTKsub) as well as the Ratkowsky extended model (RTKext) and cardinal model (CM) in the whole temperature range. With the biological background of the RTKext model, cardinal values of temperature Tmin = 6.06 °C and Tmax = 47.9 °C and water activity aw min = 0.859 were calculated and validated with cardinal values estimated by CM (Tmin = 7.72 °C, Tmax = 46.73 °C, aw min = 0.808). CM also provided other cardinal values, Topt = 40.63 °C, aw opt = 0.994, as well as optimal specific growth rate of 1.97 h–1 (at Topt and aw opt). To evaluate the goodness of fit of all models, mathematical and graphical validation was performed and the statistical indices proved appropriateness of all the secondary models used.
{"title":"Growth of Staphylococcus aureus 2064 described by predictive microbiology: From primary to secondary models","authors":"A. Medveďová, A. Havlíková, Ľ. Valík","doi":"10.2478/acs-2019-0024","DOIUrl":"https://doi.org/10.2478/acs-2019-0024","url":null,"abstract":"Abstract The growth of Staphylococcus aureus 2064 isolate in model nutrient broth was studied as affected by temperature and water activity using principles and models of predictive microbiology. Specific rates resulting from growth curves fitted by the Baranyi model were modelled by the secondary Ratkowsky model for suboptimal temperature range (RTKsub) as well as the Ratkowsky extended model (RTKext) and cardinal model (CM) in the whole temperature range. With the biological background of the RTKext model, cardinal values of temperature Tmin = 6.06 °C and Tmax = 47.9 °C and water activity aw min = 0.859 were calculated and validated with cardinal values estimated by CM (Tmin = 7.72 °C, Tmax = 46.73 °C, aw min = 0.808). CM also provided other cardinal values, Topt = 40.63 °C, aw opt = 0.994, as well as optimal specific growth rate of 1.97 h–1 (at Topt and aw opt). To evaluate the goodness of fit of all models, mathematical and graphical validation was performed and the statistical indices proved appropriateness of all the secondary models used.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":"12 1","pages":"175 - 181"},"PeriodicalIF":0.8,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48894726","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 In this paper, implementation of deep neural networks applied in process control is presented. In our approach, training of the neural network is based on model predictive control, which is popular for its ability to be tuned by the weighting matrices and for it respecting the system constraints. A neural network that can approximate the MPC behavior by mimicking the control input trajectory while the constraints on states and control input remain unimpaired by the weighting matrices is introduced. This approach is demonstrated in a simulation case study involving a continuous stirred tank reactor where a multi-component chemical reaction takes place.
{"title":"Neural network based explicit MPC for chemical reactor control","authors":"Karol Kiš, Martin Klauco","doi":"10.2478/acs-2019-0030","DOIUrl":"https://doi.org/10.2478/acs-2019-0030","url":null,"abstract":"Abstract In this paper, implementation of deep neural networks applied in process control is presented. In our approach, training of the neural network is based on model predictive control, which is popular for its ability to be tuned by the weighting matrices and for it respecting the system constraints. A neural network that can approximate the MPC behavior by mimicking the control input trajectory while the constraints on states and control input remain unimpaired by the weighting matrices is introduced. This approach is demonstrated in a simulation case study involving a continuous stirred tank reactor where a multi-component chemical reaction takes place.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":"12 1","pages":"218 - 223"},"PeriodicalIF":0.8,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44144857","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 Using the semiempirical PM6 method, structures of a rod-like [Ti40O124H81]7– model cluster and of [Ti40O124H81Cu]5– with Cu2+ coordinated at various sites were optimized in order to assess the toxicity of rutile nanoparticles. If the relative toxicity of individual Ti centers in rod-like rutile nanoparticles can be evaluated by the electron density transfer to a Cu2+ probe, its maximal values can be ascribed to the pentacoordinated corner and hexacoordinated edge Ti centers with three Ti—OH bonds. However, these centers exhibit the least negative interaction energies which can be compensated by the significantly better accessibility of the corner Ti center compared with that of the remaining ones. Ti centers with the most negative interaction energy parameters exhibit the lowest extent of electron density transfer to a Cu2+ probe. Rutile nanoparticles destruction starts at pentacoordinated Ti face centers.
{"title":"Quantum-chemical studies of rutile nanoparticles toxicity I. Defect-free rod-like model clusters","authors":"M. Breza, P. Simon","doi":"10.2478/acs-2019-0023","DOIUrl":"https://doi.org/10.2478/acs-2019-0023","url":null,"abstract":"Abstract Using the semiempirical PM6 method, structures of a rod-like [Ti40O124H81]7– model cluster and of [Ti40O124H81Cu]5– with Cu2+ coordinated at various sites were optimized in order to assess the toxicity of rutile nanoparticles. If the relative toxicity of individual Ti centers in rod-like rutile nanoparticles can be evaluated by the electron density transfer to a Cu2+ probe, its maximal values can be ascribed to the pentacoordinated corner and hexacoordinated edge Ti centers with three Ti—OH bonds. However, these centers exhibit the least negative interaction energies which can be compensated by the significantly better accessibility of the corner Ti center compared with that of the remaining ones. Ti centers with the most negative interaction energy parameters exhibit the lowest extent of electron density transfer to a Cu2+ probe. Rutile nanoparticles destruction starts at pentacoordinated Ti face centers.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":"12 1","pages":"168 - 174"},"PeriodicalIF":0.8,"publicationDate":"2019-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41410813","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. 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":"12 1","pages":"14 - 21"},"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":"12 1","pages":"82 - 90"},"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}
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