Lately, the investigations of binders from ternary system Portland cement (PC), calcium aluminate cement (CAC) and calcium sulfate ( $Coverline S$ ), have gone through a larger stage of development due to their special properties such as fast setting and rapid hardening, early strength, non-efflorescence, etc. These special properties are ensured by the binder’s microstructure, developed through hydration processes and reactions between hydrate components, which allows us to use them in special environments (aggressive environments with very low or very high level of pH, environments with high temperature, etc.). The binders from this system were simply named “dry mortars”, and provide the final user with an easy processing. In order to explain the mechanical behavior of the specimens exposed in normal curing conditions (T = 20 ± 2 °C and R.H. ≈ 95%), and with different percentages of calcium sulfate (added as hemihydrate or anhydrite), research on the microstructure of the hardened system was performed using SEM and XRD investigation techniques. The analyses have been performed on the binder pastes, hydrated for 1 and 28 days. The tests results showed that the specimen with anhydrous $Coverline S$ content had the best mechanical behavior.
近年来，三元体系硅酸盐水泥(PC)、铝酸钙水泥(CAC)和硫酸钙($Coverline S$)的粘结剂由于具有快凝结快硬化、早强、不开花等特殊性能，其研究得到了较大的发展。这些特殊性能是由粘合剂的微观结构保证的，通过水化过程和水合物组分之间的反应形成，这使我们能够在特殊环境中使用它们(pH值非常低或非常高的侵蚀环境，高温环境等)。该系统的粘合剂被简单地命名为“干砂浆”，并为最终用户提供了一个简单的加工。为了解释在正常养护条件下(T = 20±2℃，R.H.≈95%)，以及不同比例硫酸钙(以半水或硬石膏的形式添加)下暴露的试样的力学行为，采用SEM和XRD研究技术对硬化体系的微观结构进行了研究。对黏合剂膏体进行了分析，水化时间分别为1天和28天。试验结果表明，无水C + S +的试样力学性能最好。
{"title":"Binder Microstructures Developed during the Hydration Process in the System Portland Cement – Calcium Aluminate Cement – Calcium Sulfate","authors":"A. Moncea, A. Panait, G. Deák, G. Poteraș","doi":"10.1557/OPL.2016.20","DOIUrl":"https://doi.org/10.1557/OPL.2016.20","url":null,"abstract":"Lately, the investigations of binders from ternary system Portland cement (PC), calcium aluminate cement (CAC) and calcium sulfate ( $Coverline S$ ), have gone through a larger stage of development due to their special properties such as fast setting and rapid hardening, early strength, non-efflorescence, etc. These special properties are ensured by the binder’s microstructure, developed through hydration processes and reactions between hydrate components, which allows us to use them in special environments (aggressive environments with very low or very high level of pH, environments with high temperature, etc.). The binders from this system were simply named “dry mortars”, and provide the final user with an easy processing. In order to explain the mechanical behavior of the specimens exposed in normal curing conditions (T = 20 ± 2 °C and R.H. ≈ 95%), and with different percentages of calcium sulfate (added as hemihydrate or anhydrite), research on the microstructure of the hardened system was performed using SEM and XRD investigation techniques. The analyses have been performed on the binder pastes, hydrated for 1 and 28 days. The tests results showed that the specimen with anhydrous $Coverline S$ content had the best mechanical behavior.","PeriodicalId":18884,"journal":{"name":"MRS Proceedings","volume":"31 1","pages":"71-76"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73884905","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}
F. Dumitru, G. Deák, Ó. Higuera-Cobos, J. Cabrera-Marrero
Equal channel angular pressing (ECAP) was carried out on extruded ZK60 magnesium alloy until an equivalent strain of ∼4 (corresponding to 4 passes) at 523K following route Bc. The effect of the deformation on both microstructure and texture was investigated by analysis of inverse pole figures and pole figures respectively, determined by EBSD. Additionaly, the mechanical properties were evaluated through tensile tests. The ECAPed processed ZK60 alloy showed the presence of dynamic recrystallization (DRX) process, correlated with a strong basal fiber texture. The presence of pyramidal slip was also observed, which can be correlated with the presence on twin-oriented boundaries in the material. Both the grain size reduction and the existence of texture influenced the ductility of the magnesium alloy processed by ECAP, as the ductility of the ZK60 alloy after four ECAP passes increased two times in comparation with the initial (un-processed) material.
{"title":"Effect of severe plastic deformation on an extruded ZK60 magnesium alloy","authors":"F. Dumitru, G. Deák, Ó. Higuera-Cobos, J. Cabrera-Marrero","doi":"10.1557/OPL.2016.82","DOIUrl":"https://doi.org/10.1557/OPL.2016.82","url":null,"abstract":"Equal channel angular pressing (ECAP) was carried out on extruded ZK60 magnesium alloy until an equivalent strain of ∼4 (corresponding to 4 passes) at 523K following route Bc. The effect of the deformation on both microstructure and texture was investigated by analysis of inverse pole figures and pole figures respectively, determined by EBSD. Additionaly, the mechanical properties were evaluated through tensile tests. The ECAPed processed ZK60 alloy showed the presence of dynamic recrystallization (DRX) process, correlated with a strong basal fiber texture. The presence of pyramidal slip was also observed, which can be correlated with the presence on twin-oriented boundaries in the material. Both the grain size reduction and the existence of texture influenced the ductility of the magnesium alloy processed by ECAP, as the ductility of the ZK60 alloy after four ECAP passes increased two times in comparation with the initial (un-processed) material.","PeriodicalId":18884,"journal":{"name":"MRS Proceedings","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72709634","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}
V. Shapovalov, Y. Nikitenko, A. Manulyk, D. Kalashnyk
Fast-quenched alloys with amorphous and microcrystalline structures were obtained by the cooling drum spinning method during plasma-arc melting process. Thermal load measurements carried out during the melting process and the spinning of the molten material that followed, helped us to modify the existing plasma-arc equipment. Metallographic analyses of the amorphous alloys showed the influence of some quenching process parameters on the creation of their microstructure and revealed the nature of the formation of the crystal structures.
{"title":"Production of Amorphous Alloys by Special Electrometallurgy Methods","authors":"V. Shapovalov, Y. Nikitenko, A. Manulyk, D. Kalashnyk","doi":"10.1557/opl.2016.12","DOIUrl":"https://doi.org/10.1557/opl.2016.12","url":null,"abstract":"Fast-quenched alloys with amorphous and microcrystalline structures were obtained by the cooling drum spinning method during plasma-arc melting process. Thermal load measurements carried out during the melting process and the spinning of the molten material that followed, helped us to modify the existing plasma-arc equipment. Metallographic analyses of the amorphous alloys showed the influence of some quenching process parameters on the creation of their microstructure and revealed the nature of the formation of the crystal structures.","PeriodicalId":18884,"journal":{"name":"MRS Proceedings","volume":"20 1","pages":"17-22"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72938892","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}
Polypeptides are receiving increasing attention as building blocks to create nanostructures for biomedical applications. The first goal of this investigation was to explore the influence of the reaction conditions in the synthesis of well-defined dendritic graft (arborescent) polypeptides from amine-terminated poly(γ-benzyl L-glutamate) (PBG) chains. The optimization was carried out in terms of the reaction temperature, solvent, reaction time, and mole ratio of reactants and coupling agents. Size exclusion chromatography served to evaluate the grafting reaction in terms of grafting yield (fraction of side chains coupled with the substrate) and coupling efficiency (fraction of coupling sites consumed on the substrate). The maximum grafting yield and coupling efficiency achieved were 67% and 74%, respectively. These arborescent PBG substrates were subsequently grafted with poly(ethylene oxide) segments forming a hydrophilic shell, to obtain water-dispersible unimolecular micelles useful as delivery vehicles for doxorubicin.
{"title":"Arborescent Polypeptides for Sustained Drug Delivery","authors":"Mosa H. Alsehli, M. Gauthier","doi":"10.1557/OPL.2016.70","DOIUrl":"https://doi.org/10.1557/OPL.2016.70","url":null,"abstract":"Polypeptides are receiving increasing attention as building blocks to create nanostructures for biomedical applications. The first goal of this investigation was to explore the influence of the reaction conditions in the synthesis of well-defined dendritic graft (arborescent) polypeptides from amine-terminated poly(γ-benzyl L-glutamate) (PBG) chains. The optimization was carried out in terms of the reaction temperature, solvent, reaction time, and mole ratio of reactants and coupling agents. Size exclusion chromatography served to evaluate the grafting reaction in terms of grafting yield (fraction of side chains coupled with the substrate) and coupling efficiency (fraction of coupling sites consumed on the substrate). The maximum grafting yield and coupling efficiency achieved were 67% and 74%, respectively. These arborescent PBG substrates were subsequently grafted with poly(ethylene oxide) segments forming a hydrophilic shell, to obtain water-dispersible unimolecular micelles useful as delivery vehicles for doxorubicin.","PeriodicalId":18884,"journal":{"name":"MRS Proceedings","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76753690","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}
Diana Alejo-Guerra, C. León-Patiño, E. Aguilar-Reyes, José E. Bedolla-Becerril
Ni-Co/Al 2 O 3 composites with alumina particles below 0.53 µm in size were electrochemically deposited on carbon steel AISI-O1 substrates. The influence of current density (2, 3, 4 and 5 mA/cm 2 ) on the microstructure and adhesion behavior was investigated. It was found that the micro-hardness of the surface increased in 90% with respect to the plain substrate. SEM examination revealed an increased thickness from 3.7 to 10.7 µm at current density of 2 and 5 mA/cm 2 , respectively. The Co/Ni weight ratio in the coatings was determined by atomic absorption spectroscopy (AAS); the content of Co and Ni at 2 mA/cm 2 were 42.4 %Co and 57.6 %Ni, while at 5 mA/cm 2 were 44.5%Co and 55.5%Ni. The adhesion of the coatings was evaluated qualitatively according to the VDI 3198 norm; in all the cases, the adhesion was more than acceptable since no cracks or detachments were observed in the periphery of the marks. Details on the synthesis and properties of the Ni-Co/Al 2 O 3 composite coatings are presented together with the excellent properties they show despite of their thin thickness.
{"title":"Effect of Current Density on the Microstructure and Adhesion of Ni-Co/Al 2 O 3 Composite Coatings","authors":"Diana Alejo-Guerra, C. León-Patiño, E. Aguilar-Reyes, José E. Bedolla-Becerril","doi":"10.1557/OPL.2016.67","DOIUrl":"https://doi.org/10.1557/OPL.2016.67","url":null,"abstract":"Ni-Co/Al 2 O 3 composites with alumina particles below 0.53 µm in size were electrochemically deposited on carbon steel AISI-O1 substrates. The influence of current density (2, 3, 4 and 5 mA/cm 2 ) on the microstructure and adhesion behavior was investigated. It was found that the micro-hardness of the surface increased in 90% with respect to the plain substrate. SEM examination revealed an increased thickness from 3.7 to 10.7 µm at current density of 2 and 5 mA/cm 2 , respectively. The Co/Ni weight ratio in the coatings was determined by atomic absorption spectroscopy (AAS); the content of Co and Ni at 2 mA/cm 2 were 42.4 %Co and 57.6 %Ni, while at 5 mA/cm 2 were 44.5%Co and 55.5%Ni. The adhesion of the coatings was evaluated qualitatively according to the VDI 3198 norm; in all the cases, the adhesion was more than acceptable since no cracks or detachments were observed in the periphery of the marks. Details on the synthesis and properties of the Ni-Co/Al 2 O 3 composite coatings are presented together with the excellent properties they show despite of their thin thickness.","PeriodicalId":18884,"journal":{"name":"MRS Proceedings","volume":"384 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80742490","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}
Development of polymers with antimicrobial characteristics can avoid deterioration and assist in containing spread of pathogens harmful to human health. This study aimed to compare the antimicrobial and mechanical properties of polymeric matrices containing organic antimicrobial additives. Silver organomodified bentonite (Ag_bentonite) and organochlorine molecule in a masterbatch based polyethylene (Cl_PE) were tested in proportion of 2% in a thermoplastic elastomeric formulation. The polymeric matrices were prepared by melt mixing and evaluated in tensile and antimicrobial properties against Staphylococcus aureus ( S. aureus ) and Escherichia coli ( E. coli) strains . The additives were characterized by thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The nanoscale of Ag_bentonite was verified by SEM. TGA assay showed that Cl_PE is more sensitive to heat than Ag_bentonite. As a result of this lower thermal stability, the addition of Cl_PE reduced the tensile properties of the compound. The sample with Cl_PE was effective against both bacterial strains, reducing the populations of S. aureus and E. coli in 99 and 96%, respectively. The addition of Ag_bentonite did not affect the tensile strength and decreased in 97 and 40% S. aureus and E. coli populations, respectively. The results indicate that the use of organic additives is promissory, but further modifications in processing must be necessary.
{"title":"Organic additives as antimicrobial agents in thermoplastics compounds","authors":"D. Tomacheski, M. Pittol, V. Ribeiro, R. Santana","doi":"10.1557/OPL.2016.54","DOIUrl":"https://doi.org/10.1557/OPL.2016.54","url":null,"abstract":"Development of polymers with antimicrobial characteristics can avoid deterioration and assist in containing spread of pathogens harmful to human health. This study aimed to compare the antimicrobial and mechanical properties of polymeric matrices containing organic antimicrobial additives. Silver organomodified bentonite (Ag_bentonite) and organochlorine molecule in a masterbatch based polyethylene (Cl_PE) were tested in proportion of 2% in a thermoplastic elastomeric formulation. The polymeric matrices were prepared by melt mixing and evaluated in tensile and antimicrobial properties against Staphylococcus aureus ( S. aureus ) and Escherichia coli ( E. coli) strains . The additives were characterized by thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The nanoscale of Ag_bentonite was verified by SEM. TGA assay showed that Cl_PE is more sensitive to heat than Ag_bentonite. As a result of this lower thermal stability, the addition of Cl_PE reduced the tensile properties of the compound. The sample with Cl_PE was effective against both bacterial strains, reducing the populations of S. aureus and E. coli in 99 and 96%, respectively. The addition of Ag_bentonite did not affect the tensile strength and decreased in 97 and 40% S. aureus and E. coli populations, respectively. The results indicate that the use of organic additives is promissory, but further modifications in processing must be necessary.","PeriodicalId":18884,"journal":{"name":"MRS Proceedings","volume":"107 S119","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91435674","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}
{"title":"Simulation of Mechanical Elongation and Compression of Nanostructures","authors":"S. Mejía-Rosales, Carlos Fernández-Navarro","doi":"10.1557/OPL.2016.42","DOIUrl":"https://doi.org/10.1557/OPL.2016.42","url":null,"abstract":"","PeriodicalId":18884,"journal":{"name":"MRS Proceedings","volume":"101 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88392172","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}
Violeta Campos-Cornelio, N. Flores-Ramírez, S. R. Vasquez‐Garcia, L. Domratcheva-Lvova, L. García-González
Chitin nanowhiskers were obtained with the purpose to be used as astaxanthin protectors against the photo and thermal degradation. These nanostructures were generated by a freezing/thawing procedure using two stirring methods: mechanical and sonication, which were named as FTM and FTS respectively. Morphological and spectroscopic studies were carried out on chitin nanowhiskers by scanning electronic microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Through a SEM analysis, chitin fibers were found uniformly spaced and oriented with the width ranged from of 20-40 nm. Furthermore, the nanowhiskers obtained by FTM showed long and flattened structures and bundles of homogeneous sizes, which have the capacity of being sites of stress concentration. In contrast, by FTS, the nanowhiskers showed coarse fibers exhibiting numerous peaks. By comparing the two methods is appreciated that FTS method provides more surface area, giving more sites for functionalization. Fourier transform infrared spectroscopy (FTIR) allowed the determination of free movement of functional groups on the surface of samples obtained by FTM and FTS methods. Significant differences of signals in the spectra indicate that there were more unassociated amides in the nanowhiskers obtained by FTS than by FTM.
{"title":"Morphological and Spectroscopic Studies of Chitin Nanowhiskers","authors":"Violeta Campos-Cornelio, N. Flores-Ramírez, S. R. Vasquez‐Garcia, L. Domratcheva-Lvova, L. García-González","doi":"10.1557/OPL.2016.46","DOIUrl":"https://doi.org/10.1557/OPL.2016.46","url":null,"abstract":"Chitin nanowhiskers were obtained with the purpose to be used as astaxanthin protectors against the photo and thermal degradation. These nanostructures were generated by a freezing/thawing procedure using two stirring methods: mechanical and sonication, which were named as FTM and FTS respectively. Morphological and spectroscopic studies were carried out on chitin nanowhiskers by scanning electronic microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Through a SEM analysis, chitin fibers were found uniformly spaced and oriented with the width ranged from of 20-40 nm. Furthermore, the nanowhiskers obtained by FTM showed long and flattened structures and bundles of homogeneous sizes, which have the capacity of being sites of stress concentration. In contrast, by FTS, the nanowhiskers showed coarse fibers exhibiting numerous peaks. By comparing the two methods is appreciated that FTS method provides more surface area, giving more sites for functionalization. Fourier transform infrared spectroscopy (FTIR) allowed the determination of free movement of functional groups on the surface of samples obtained by FTM and FTS methods. Significant differences of signals in the spectra indicate that there were more unassociated amides in the nanowhiskers obtained by FTS than by FTM.","PeriodicalId":18884,"journal":{"name":"MRS Proceedings","volume":"64 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87581756","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}
Ramiro Infante-Martínez, E. Saldívar‐Guerra, O. Pérez‐Camacho, M. García-Zamora, Víctor E Comparán-Padilla
{"title":"Modelling the Complete Molecular Weight Distribution in Chain Growth Polymerizations","authors":"Ramiro Infante-Martínez, E. Saldívar‐Guerra, O. Pérez‐Camacho, M. García-Zamora, Víctor E Comparán-Padilla","doi":"10.1557/OPL.2016.83","DOIUrl":"https://doi.org/10.1557/OPL.2016.83","url":null,"abstract":"","PeriodicalId":18884,"journal":{"name":"MRS Proceedings","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84493420","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}
Rosa E. Lazo-Jiménez, J. Chávez-Carvayar, A. Herrera-González, Valentin Islas-Pérez, M. Carreón-Castro
{"title":"Nanostructured LB films developed from poly(p-acryloylaminophenylmethylphosphonic) acid","authors":"Rosa E. Lazo-Jiménez, J. Chávez-Carvayar, A. Herrera-González, Valentin Islas-Pérez, M. Carreón-Castro","doi":"10.1557/OPL.2016.74","DOIUrl":"https://doi.org/10.1557/OPL.2016.74","url":null,"abstract":"","PeriodicalId":18884,"journal":{"name":"MRS Proceedings","volume":"136 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77478775","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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