Pub Date : 2020-01-01DOI: 10.17277/amt.2020.02.pp.046-056
A. Mashhadani, V. Pershin
The paper considers methods for concrete modification using low-layer graphene and graphene oxide. It was found that graphene oxide and low-layer graphene obtained by liquid-phase shear exfoliation significantly increase the strength of concrete. In our opinion, low-layer graphene has better prospects since it is cheaper and its production technology is environmentally friendly. The viability and future of graphene largely depends on the availability of such a method that allows mass production of high-quality graphene at an affordable price. In this regard, liquid-phase separation of graphite with the formation of low-layer graphene, which can be used to modify concrete, turned out to be a competitive solution. The following main tasks were formulated in order to solve the organizational problems of low-layer graphene industrial production: reducing the concentration of low-layer graphene in concrete; increasing the concentration of low-layer graphene in suspension; developing an industrial technology for the production of concentrate with a high content of low-layer graphene; conducting full-scale experimental studies to determine the optimal concentration of low-layer graphene in concrete.
{"title":"Concrete Modification Using Graphene and Graphene Oxide","authors":"A. Mashhadani, V. Pershin","doi":"10.17277/amt.2020.02.pp.046-056","DOIUrl":"https://doi.org/10.17277/amt.2020.02.pp.046-056","url":null,"abstract":"The paper considers methods for concrete modification using low-layer graphene and graphene oxide. It was found that graphene oxide and low-layer graphene obtained by liquid-phase shear exfoliation significantly increase the strength of concrete. In our opinion, low-layer graphene has better prospects since it is cheaper and its production technology is environmentally friendly. The viability and future of graphene largely depends on the availability of such a method that allows mass production of high-quality graphene at an affordable price. In this regard, liquid-phase separation of graphite with the formation of low-layer graphene, which can be used to modify concrete, turned out to be a competitive solution. The following main tasks were formulated in order to solve the organizational problems of low-layer graphene industrial production: reducing the concentration of low-layer graphene in concrete; increasing the concentration of low-layer graphene in suspension; developing an industrial technology for the production of concentrate with a high content of low-layer graphene; conducting full-scale experimental studies to determine the optimal concentration of low-layer graphene in concrete.","PeriodicalId":13355,"journal":{"name":"Image Journal of Advanced Materials and Technologies","volume":"238 1","pages":"046-056"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80409392","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}
Pub Date : 2020-01-01DOI: 10.17277/amt.2020.02.pp.003-009
Z. T. Turganov, A. Stolin, P. Bazhin, O. Averichev
The paper presents the experimental study results of the powder refractory materials morphology of the Ti–C system obtained by SHS grinding in a closed reactor. The microand macrostructure is considered, the values of the dispersion of the powder are given depending on the grinding modes of the synthesis products. Under optimal grinding conditions, roundshaped titanium carbide with a fineness of 20–60 microns was obtained. The content of the oxide phase in the titanium carbide powder decreases from 2 to 9 times with increasing grinding intensity, and does not exceed 5 mass. %
{"title":"Structural Features of the Refractory Powder Materials Based on Titanium Carbide Obtained by SHS-Grinding","authors":"Z. T. Turganov, A. Stolin, P. Bazhin, O. Averichev","doi":"10.17277/amt.2020.02.pp.003-009","DOIUrl":"https://doi.org/10.17277/amt.2020.02.pp.003-009","url":null,"abstract":"The paper presents the experimental study results of the powder refractory materials morphology of the Ti–C system obtained by SHS grinding in a closed reactor. The microand macrostructure is considered, the values of the dispersion of the powder are given depending on the grinding modes of the synthesis products. Under optimal grinding conditions, roundshaped titanium carbide with a fineness of 20–60 microns was obtained. The content of the oxide phase in the titanium carbide powder decreases from 2 to 9 times with increasing grinding intensity, and does not exceed 5 mass. %","PeriodicalId":13355,"journal":{"name":"Image Journal of Advanced Materials and Technologies","volume":"16 1","pages":"003-009"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82027515","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}
Pub Date : 2020-01-01DOI: 10.17277/amt.2020.02.pp.010-018
E. A. Mun, B. Zhaisanbayeva
Over the past few decades, nanoparticles have been attracting significant attention of researches in chemical, biomedical, pharmaceutical sciences, due to their unique physicochemical properties. This includes ultra small size, large surface area, good biocompatibility and high reactivity. In particular, nanoparticles are promising for pharmaceutical and biomedical fields, as they have been applied as drug carriers and diagnostic tools. However, nanoparticles can be easily detected and cleared out by the mononuclear phagocyte system before delivering the drug to the target site. One of the most widely applied approaches to prolong circulation of nanoparticles is to modify their surfaces with polyethylene glycol (PEG). This paper describes how PEGylation occurs, as well as application of various PEGylated nanoparticles in drug delivery.
{"title":"The Role of Nanoparticle PEGylation in Drug Delivery","authors":"E. A. Mun, B. Zhaisanbayeva","doi":"10.17277/amt.2020.02.pp.010-018","DOIUrl":"https://doi.org/10.17277/amt.2020.02.pp.010-018","url":null,"abstract":"Over the past few decades, nanoparticles have been attracting significant attention of researches in chemical, biomedical, pharmaceutical sciences, due to their unique physicochemical properties. This includes ultra small size, large surface area, good biocompatibility and high reactivity. In particular, nanoparticles are promising for pharmaceutical and biomedical fields, as they have been applied as drug carriers and diagnostic tools. However, nanoparticles can be easily detected and cleared out by the mononuclear phagocyte system before delivering the drug to the target site. One of the most widely applied approaches to prolong circulation of nanoparticles is to modify their surfaces with polyethylene glycol (PEG). This paper describes how PEGylation occurs, as well as application of various PEGylated nanoparticles in drug delivery.","PeriodicalId":13355,"journal":{"name":"Image Journal of Advanced Materials and Technologies","volume":"52 1","pages":"010-018"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72671295","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}
Pub Date : 2020-01-01DOI: 10.17277/amt.2020.03.pp.056-063
M. Nasraoui, Yu. V. Litovka, V. Dolmatov
A method to increase the microhardness of the chromium galvanic coating by adding a mixture of carbon nanomaterials (nanodiamonds, single-walled and multi-walled nanotubes, graphene oxide) into a standard chromium galvanic coating electrolyte was proposed. The increase in the microhardness of the chromium galvanic coating was revealed and explained. This is due to a combination of two mechanisms: the introduction of nanodiamonds into the crystal lattice of the coating metal and the appearance of additional crystallization centers on defects in carbon nanotubes. The method of obtaining parts with a higher service life when using traditional chromium galvanic coating, as well as when using multi-walled carbon nanotubes, single-walled carbon nanotubes, nanodiamonds, and graphene oxide separately, was demonstrated. The best result was obtained using a mixture of nanodiamonds and multi-walled carbon nanotubes. The microhardness of the nanomodified chromium galvanic coating was measured, and it was found to increase by 27 %.
{"title":"The Effect of Combinations of Carbon Nanomaterials on the Microhardness of the Chromium Galvanic Coating","authors":"M. Nasraoui, Yu. V. Litovka, V. Dolmatov","doi":"10.17277/amt.2020.03.pp.056-063","DOIUrl":"https://doi.org/10.17277/amt.2020.03.pp.056-063","url":null,"abstract":"A method to increase the microhardness of the chromium galvanic coating by adding a mixture of carbon nanomaterials (nanodiamonds, single-walled and multi-walled nanotubes, graphene oxide) into a standard chromium galvanic coating electrolyte was proposed. The increase in the microhardness of the chromium galvanic coating was revealed and explained. This is due to a combination of two mechanisms: the introduction of nanodiamonds into the crystal lattice of the coating metal and the appearance of additional crystallization centers on defects in carbon nanotubes. The method of obtaining parts with a higher service life when using traditional chromium galvanic coating, as well as when using multi-walled carbon nanotubes, single-walled carbon nanotubes, nanodiamonds, and graphene oxide separately, was demonstrated. The best result was obtained using a mixture of nanodiamonds and multi-walled carbon nanotubes. The microhardness of the nanomodified chromium galvanic coating was measured, and it was found to increase by 27 %.","PeriodicalId":13355,"journal":{"name":"Image Journal of Advanced Materials and Technologies","volume":"30 1","pages":"056-063"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87484560","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}
Pub Date : 2020-01-01DOI: 10.17277/amt.2020.04.pp.021-028
E. Mkrtchyan, E. Neskoromnaya, I. Burakova, O. A. Ananyeva, N. A. Revyakina, A. Babkin, T. S. Kuznetsova, D. Kurnosov, A. Burakov
The comparative adsorption capacity of graphene aerogel and activated coconut carbon in the process of removing the main cationic synthetic dye, methylene blue (MB), from aqueous solutions with an initial concentration of 150 mg/l was investigated. The characteristics of the new material have been determined using scanning electron microscopy, thermogravimetry, and Raman spectroscopy. The values of the adsorption capacity of graphene aerogel – 420 mg/g and activated carbon – 205 mg/g were established. The saturation time in the presence of graphene aerogel was 7 min. The experimental data were processed using kinetic models – pseudo-first and pseudo-second order, Elovich and intraparticle diffusion. According to the results obtained, graphene aerogel is a promising sorption material in the extraction of molecular organic pollutants, namely, synthetic dyes, demonstrating a high efficiency of the target pollutant removal.
{"title":"Comparative Analysis of the Adsorption Kinetics of the Methylene Blue Dye on Graphene Aerogel and Activated Coconut Carbon","authors":"E. Mkrtchyan, E. Neskoromnaya, I. Burakova, O. A. Ananyeva, N. A. Revyakina, A. Babkin, T. S. Kuznetsova, D. Kurnosov, A. Burakov","doi":"10.17277/amt.2020.04.pp.021-028","DOIUrl":"https://doi.org/10.17277/amt.2020.04.pp.021-028","url":null,"abstract":"The comparative adsorption capacity of graphene aerogel and activated coconut carbon in the process of removing the main cationic synthetic dye, methylene blue (MB), from aqueous solutions with an initial concentration of 150 mg/l was investigated. The characteristics of the new material have been determined using scanning electron microscopy, thermogravimetry, and Raman spectroscopy. The values of the adsorption capacity of graphene aerogel – 420 mg/g and activated carbon – 205 mg/g were established. The saturation time in the presence of graphene aerogel was 7 min. The experimental data were processed using kinetic models – pseudo-first and pseudo-second order, Elovich and intraparticle diffusion. According to the results obtained, graphene aerogel is a promising sorption material in the extraction of molecular organic pollutants, namely, synthetic dyes, demonstrating a high efficiency of the target pollutant removal.","PeriodicalId":13355,"journal":{"name":"Image Journal of Advanced Materials and Technologies","volume":"3 1","pages":"021-028"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88751835","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}
Pub Date : 2020-01-01DOI: 10.17277/amt.2020.01.pp.049-053
M. Barshutina, P. Musienko, A. Tkachev
This paper deals with mathematical modeling of the elastic modulus of polymer composites based on carbon nanotubes. These composites are promising materials for electrodes of flexible medical implants due to their good conductivity, low elastic modulus and high biocompatibility. However, to achieve a high level of affinity of these composites to biological tissues, it is necessary to ensure the maximum possible overlapping of composite elastic moduli withelastic moduli of tissues. As a result of theoretical and experimental studies, we obtained the mathematical model that allows calculating the optimal concentrations of carbon nanotubes in composites to reach an elastic modulus of particular tissues.
{"title":"Modeling of Elastic Modulus of CNT/Silicone Composites Designed for Medical Applications","authors":"M. Barshutina, P. Musienko, A. Tkachev","doi":"10.17277/amt.2020.01.pp.049-053","DOIUrl":"https://doi.org/10.17277/amt.2020.01.pp.049-053","url":null,"abstract":"This paper deals with mathematical modeling of the elastic modulus of polymer composites based on carbon nanotubes. These composites are promising materials for electrodes of flexible medical implants due to their good conductivity, low elastic modulus and high biocompatibility. However, to achieve a high level of affinity of these composites to biological tissues, it is necessary to ensure the maximum possible overlapping of composite elastic moduli withelastic moduli of tissues. As a result of theoretical and experimental studies, we obtained the mathematical model that allows calculating the optimal concentrations of carbon nanotubes in composites to reach an elastic modulus of particular tissues.","PeriodicalId":13355,"journal":{"name":"Image Journal of Advanced Materials and Technologies","volume":"372 1","pages":"049-053"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77757646","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}
Pub Date : 2020-01-01DOI: 10.17277/amt.2020.03.pp.047-055
V. Dolgunin, O. Ivanov, S. A. Akopyan
The investigation results of granular temperature during rapid gravity flow of granular medium on a rough chute are discussed. The granular temperature is determined as the kinetic energy of several forms of mutual displacements of particles. The influence of the chute angle on the value ratio of different components of granular temperature is analyzed. The components of granular temperature induced by fluctuation, shear and transversal mutual displacements of particles were taken into account.
{"title":"Quasithermal Effects During Rapid Gravity Flow of a Granular Medium","authors":"V. Dolgunin, O. Ivanov, S. A. Akopyan","doi":"10.17277/amt.2020.03.pp.047-055","DOIUrl":"https://doi.org/10.17277/amt.2020.03.pp.047-055","url":null,"abstract":"The investigation results of granular temperature during rapid gravity flow of granular medium on a rough chute are discussed. The granular temperature is determined as the kinetic energy of several forms of mutual displacements of particles. The influence of the chute angle on the value ratio of different components of granular temperature is analyzed. The components of granular temperature induced by fluctuation, shear and transversal mutual displacements of particles were taken into account.","PeriodicalId":13355,"journal":{"name":"Image Journal of Advanced Materials and Technologies","volume":"80 1","pages":"047-055"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73291912","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}
Pub Date : 2020-01-01DOI: 10.17277/amt.2020.03.pp.028-032
A. Popova, R. Aliev, I. Shubin
Creation of innovative products and technological breakthrough – phrases most often used in relation to objects located in the nanoscale area. Carbon nanomaterials (CNMs) of various morphologies and structures, which include nanotubes, graphene, nanoporous carbon, are one of the most studied materials of the nanotechnology industry at present. This is due primarily to the fact that their physico-mechanical and physico-chemical characteristics have a direct effect on the final product. At the same time, for a number of applications, the best performance is achieved at the highest possible values of specific surface parameters and porosity. Methods and an experimental technology for producing microand mesoporous carbon material have been developed. Depending on the feedstock and technological synthesis modes, a nanoporous carbon material is obtained with a predominance of microor mesopores, with a BET specific surface area in the range of 2000–4000 m/g. The technology includes carbonization of the starting materials and subsequent chemical activation. The obtained activated carbon material can be used as sorbents for gaseous media, both in purification systems and as gas batteries for safe storage and transportation systems, as well as for solving a number of environmental problems.
{"title":"Features of Nanoporous Carbon Material Synthesis","authors":"A. Popova, R. Aliev, I. Shubin","doi":"10.17277/amt.2020.03.pp.028-032","DOIUrl":"https://doi.org/10.17277/amt.2020.03.pp.028-032","url":null,"abstract":"Creation of innovative products and technological breakthrough – phrases most often used in relation to objects located in the nanoscale area. Carbon nanomaterials (CNMs) of various morphologies and structures, which include nanotubes, graphene, nanoporous carbon, are one of the most studied materials of the nanotechnology industry at present. This is due primarily to the fact that their physico-mechanical and physico-chemical characteristics have a direct effect on the final product. At the same time, for a number of applications, the best performance is achieved at the highest possible values of specific surface parameters and porosity. Methods and an experimental technology for producing microand mesoporous carbon material have been developed. Depending on the feedstock and technological synthesis modes, a nanoporous carbon material is obtained with a predominance of microor mesopores, with a BET specific surface area in the range of 2000–4000 m/g. The technology includes carbonization of the starting materials and subsequent chemical activation. The obtained activated carbon material can be used as sorbents for gaseous media, both in purification systems and as gas batteries for safe storage and transportation systems, as well as for solving a number of environmental problems.","PeriodicalId":13355,"journal":{"name":"Image Journal of Advanced Materials and Technologies","volume":"156 1","pages":"028-032"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84384364","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}
Pub Date : 2020-01-01DOI: 10.17277/amt.2020.01.pp.064-067
R. Garipov, S. Khantimerov, N. Suleimanov
The changes in the morphology of conical carbon nanotubes and composition of functional groups on their surface during liquid-phase functionalization in various solutions were investigated. The dependence of the type of functional groups on the composition of oxidizing agents was studied. The influence of the type of functional groups on the carbon nanotubes surface on the conductive properties of the polymer composite material based on them was established.
{"title":"Investigation of the Carbon Nanotubes Functionalization Effect on the Composite Material Conductive Properties","authors":"R. Garipov, S. Khantimerov, N. Suleimanov","doi":"10.17277/amt.2020.01.pp.064-067","DOIUrl":"https://doi.org/10.17277/amt.2020.01.pp.064-067","url":null,"abstract":"The changes in the morphology of conical carbon nanotubes and composition of functional groups on their surface during liquid-phase functionalization in various solutions were investigated. The dependence of the type of functional groups on the composition of oxidizing agents was studied. The influence of the type of functional groups on the carbon nanotubes surface on the conductive properties of the polymer composite material based on them was established.","PeriodicalId":13355,"journal":{"name":"Image Journal of Advanced Materials and Technologies","volume":" 8","pages":"064-067"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91515701","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}
Pub Date : 2020-01-01DOI: 10.17277/amt.2020.03.pp.064-067
A. Konstantinov, M. Antipov, P. Bazhin, A. Stolin
In this paper, the effect of the process parameters of the SHS-extrusion method (the delay time before applying pressure, the speed of movement of the press plunger) on the length and quality of extruded cylindrical rods with a diameter of 3 mm, obtained from TiB – 30 wt. % Ti materials, was studied. Their optimal values were determined: the delay time interval was 3–3.5 s, the press plunger speed interval was 40–50 mm/s. Using the results of SEM and XRD, the structural features of the obtained materials were studied, and their texture was determined. The physical and mechanical characteristics of the obtained materials were measured: porosity, hardness, microhardness.
{"title":"Regularities of the Effect of Process Parameters of SHS-Extrusion on the Structure and Properties of Long-Dimensional Rods from TiB / 30 wt. % Ti Materials","authors":"A. Konstantinov, M. Antipov, P. Bazhin, A. Stolin","doi":"10.17277/amt.2020.03.pp.064-067","DOIUrl":"https://doi.org/10.17277/amt.2020.03.pp.064-067","url":null,"abstract":"In this paper, the effect of the process parameters of the SHS-extrusion method (the delay time before applying pressure, the speed of movement of the press plunger) on the length and quality of extruded cylindrical rods with a diameter of 3 mm, obtained from TiB – 30 wt. % Ti materials, was studied. Their optimal values were determined: the delay time interval was 3–3.5 s, the press plunger speed interval was 40–50 mm/s. Using the results of SEM and XRD, the structural features of the obtained materials were studied, and their texture was determined. The physical and mechanical characteristics of the obtained materials were measured: porosity, hardness, microhardness.","PeriodicalId":13355,"journal":{"name":"Image Journal of Advanced Materials and Technologies","volume":"14 1","pages":"064-067"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90660957","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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