Pub Date : 2022-02-28DOI: 10.15828/2075-8545-2022-14-1-18-26
L. Ivanov, L.D. Xu, E. S. Bokova, A. D. Ishkov, O. Borisova
: Introduction. Advanced technologies impress people’s imagination demonstrating the latest achievements (materials, methods, systems, technologies, devices etc.) that dramatically change the world. This, first of all, concerns nanotechnological inventions designed by scientists, engineers and specialists from different countries. Main part. The article provides an abstract overview of inventions of scientists, engineers and specialists from different countries: Germany, Russia, USA, et al. The results of the creative activity of scientists, engineers and specialists, including inventions in the field of nanotechnology and nanomaterials allow, when introduced to industry, achieving a significant effect in construction, housing and communal services, and related sectors of the economy. For example, the task resolved by the invention «A composition on the basis of oxide nanostructures to provide surface with superhydrophobic properties», means to design a new method of obtaining materials with superhydrophobic properties which possess improved performance and functional characteristics which can be applied in various areas: power engineering, electronics, machine-building, construction, ship-building, aviation, aerospace and food industries. The feature of the invention is that the surfaces demonstrate superhydrophobic properties and, as a result of that, their applying allows protecting metal structures, such as power lines, frame structures, roofs, from ice formation and dirtying. The technical result is possible due to the use of composition on the basis of oxide nanostructures to provide surface with superhydrophobic properties. The composition contains tetraethoxysilane and tetraisopropyl titanate as structure-forming agents, hexamethyldisilazane as hydrophobic element, isopropyl alcohol as dissolvent, non-spheric nanocrystal titanium dioxide with particle size from 10 to 50 nm as a grow accelerator of anisotropic structures to provide specified roughness of the surface. The specialist can be also interested in the following inventions in the area of nanotechnologies: a composite heat-conducting material on the basis of nanoliquid, a nanocomposite material on the basis of potassium titanate, a method of obtaining of nanodispersed powders, hybrid supercondenser on the basis of nanosized nickel hydroxide, etc. Conclusion. One of the most challenging tasks the economy of every country faces is to increase industrial competitiveness through technological upgrade. From the side of the state and companies the principal object to control in this process are the people and enterprises dealing with introduction of inventions and new technologies.
{"title":"Inventions in the area of nanomaterials and nanotechnologies. Part I","authors":"L. Ivanov, L.D. Xu, E. S. Bokova, A. D. Ishkov, O. Borisova","doi":"10.15828/2075-8545-2022-14-1-18-26","DOIUrl":"https://doi.org/10.15828/2075-8545-2022-14-1-18-26","url":null,"abstract":": Introduction. Advanced technologies impress people’s imagination demonstrating the latest achievements (materials, methods, systems, technologies, devices etc.) that dramatically change the world. This, first of all, concerns nanotechnological inventions designed by scientists, engineers and specialists from different countries. Main part. The article provides an abstract overview of inventions of scientists, engineers and specialists from different countries: Germany, Russia, USA, et al. The results of the creative activity of scientists, engineers and specialists, including inventions in the field of nanotechnology and nanomaterials allow, when introduced to industry, achieving a significant effect in construction, housing and communal services, and related sectors of the economy. For example, the task resolved by the invention «A composition on the basis of oxide nanostructures to provide surface with superhydrophobic properties», means to design a new method of obtaining materials with superhydrophobic properties which possess improved performance and functional characteristics which can be applied in various areas: power engineering, electronics, machine-building, construction, ship-building, aviation, aerospace and food industries. The feature of the invention is that the surfaces demonstrate superhydrophobic properties and, as a result of that, their applying allows protecting metal structures, such as power lines, frame structures, roofs, from ice formation and dirtying. The technical result is possible due to the use of composition on the basis of oxide nanostructures to provide surface with superhydrophobic properties. The composition contains tetraethoxysilane and tetraisopropyl titanate as structure-forming agents, hexamethyldisilazane as hydrophobic element, isopropyl alcohol as dissolvent, non-spheric nanocrystal titanium dioxide with particle size from 10 to 50 nm as a grow accelerator of anisotropic structures to provide specified roughness of the surface. The specialist can be also interested in the following inventions in the area of nanotechnologies: a composite heat-conducting material on the basis of nanoliquid, a nanocomposite material on the basis of potassium titanate, a method of obtaining of nanodispersed powders, hybrid supercondenser on the basis of nanosized nickel hydroxide, etc. Conclusion. One of the most challenging tasks the economy of every country faces is to increase industrial competitiveness through technological upgrade. From the side of the state and companies the principal object to control in this process are the people and enterprises dealing with introduction of inventions and new technologies.","PeriodicalId":43938,"journal":{"name":"Nanotechnologies in Construction-A Scientific Internet-Journal","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2022-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86525642","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 : 2022-02-28DOI: 10.15828/2075-8545-2022-14-1-5-10
M. Frolova
{"title":"Aspects of determining the aggregative stability of water suspensions of mineral powders for building composites","authors":"M. Frolova","doi":"10.15828/2075-8545-2022-14-1-5-10","DOIUrl":"https://doi.org/10.15828/2075-8545-2022-14-1-5-10","url":null,"abstract":"","PeriodicalId":43938,"journal":{"name":"Nanotechnologies in Construction-A Scientific Internet-Journal","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2022-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75155431","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 : 2021-12-22DOI: 10.15828/2075-8545-2021-13-6-343-349
I. Massalimov, B. Massalimov, A. Mustafin
Introduction. Impregnation with a solution based on calcium polysulfide showed excellent results in the hydrophobization of concrete, brick and shell rock due to the formation of a water-repellent coating of sulfur nanoparticles on the surface of their pores. This paper presents the data of studying the properties of aerated concrete, widespread in construction practice, which has a widely developed pore system. Materials and methods. The data on the penetration of water into the studied samples of aerated concrete using the methods of visual examination, including electron microscopy, as well as methods for measuring the water absorption and strength of the samples impregnated with a solution based on calcium polysulfide are presented. Results. It is shown that aerated concrete impregnated with calcium polysulfide, despite the developed pore system, acquires pronounced water-repellent properties. It was found that the optimal processing time is 20 minutes, and the increase in the water-repellent properties of aerated concrete depends on the density of the impregnating solution. As a result of impregnation of aerated concrete by immersion in a solution with a density of 1.16 g/cm3, a decrease in 3.7 times occurs, and when treated with a solution with a density of 1.25 g/cm3, it decreases 6.8 times and becomes equal to 6%. For samples processed with the use of vacuum, in the case of processing a solution with a density of 1.16 g/cm3, water absorption decreases by 7.9 times, and when processing with a solution using vacuum, it decreases 19.8 times, while the compressive strength increases by 1.7 once. Samples of aerated concrete, treated with a polysulfide-based solution with a brush, showed that in this case, water absorption in the sprinkling mode decreases to values of 1.5–2.0%. Discussion. It is noted that during the surface treatment of aerated concrete, a chemically resistant, water-repellent layer 3–3.5 cm thick is formed, which reliably protects the material from the penetration of water and chemicals. The results of the performed experiments give reason to believe that on the surface of the pores of aerated concrete treated with a solution based on calcium polysulfide, as well as on the surface of the pores of previously investigated materials, a nanosized coating is formed of sulfur particles that hydrophobic aerated concrete. Conclusions. Comparison of the results for aerated concrete with excellent data for concrete, brick, shell rock shows that the efficiency for aerated concrete is no less and allows us to recommend the specified solution for long-term protection of the surface of aerated concrete walls.
{"title":"Improving the performance characteristics of gas concrete impregnated with calcium polysulfide","authors":"I. Massalimov, B. Massalimov, A. Mustafin","doi":"10.15828/2075-8545-2021-13-6-343-349","DOIUrl":"https://doi.org/10.15828/2075-8545-2021-13-6-343-349","url":null,"abstract":"Introduction. Impregnation with a solution based on calcium polysulfide showed excellent results in the hydrophobization of concrete, brick and shell rock due to the formation of a water-repellent coating of sulfur nanoparticles on the surface of their pores. This paper presents the data of studying the properties of aerated concrete, widespread in construction practice, which has a widely developed pore system. Materials and methods. The data on the penetration of water into the studied samples of aerated concrete using the methods of visual examination, including electron microscopy, as well as methods for measuring the water absorption and strength of the samples impregnated with a solution based on calcium polysulfide are presented. Results. It is shown that aerated concrete impregnated with calcium polysulfide, despite the developed pore system, acquires pronounced water-repellent properties. It was found that the optimal processing time is 20 minutes, and the increase in the water-repellent properties of aerated concrete depends on the density of the impregnating solution. As a result of impregnation of aerated concrete by immersion in a solution with a density of 1.16 g/cm3, a decrease in 3.7 times occurs, and when treated with a solution with a density of 1.25 g/cm3, it decreases 6.8 times and becomes equal to 6%. For samples processed with the use of vacuum, in the case of processing a solution with a density of 1.16 g/cm3, water absorption decreases by 7.9 times, and when processing with a solution using vacuum, it decreases 19.8 times, while the compressive strength increases by 1.7 once. Samples of aerated concrete, treated with a polysulfide-based solution with a brush, showed that in this case, water absorption in the sprinkling mode decreases to values of 1.5–2.0%. Discussion. It is noted that during the surface treatment of aerated concrete, a chemically resistant, water-repellent layer 3–3.5 cm thick is formed, which reliably protects the material from the penetration of water and chemicals. The results of the performed experiments give reason to believe that on the surface of the pores of aerated concrete treated with a solution based on calcium polysulfide, as well as on the surface of the pores of previously investigated materials, a nanosized coating is formed of sulfur particles that hydrophobic aerated concrete. Conclusions. Comparison of the results for aerated concrete with excellent data for concrete, brick, shell rock shows that the efficiency for aerated concrete is no less and allows us to recommend the specified solution for long-term protection of the surface of aerated concrete walls.","PeriodicalId":43938,"journal":{"name":"Nanotechnologies in Construction-A Scientific Internet-Journal","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2021-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85335873","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 : 2021-12-22DOI: 10.15828/2075-8545-2021-13-6-358-364
A. Mazitova, Z.F. Bulatasov, I. Zaripov, Yu. E. Sapozhnikov, I. Vikhareva
{"title":"Evaluation of the efficiency of using new environmentally friendly PVC additives based on adipic acid","authors":"A. Mazitova, Z.F. Bulatasov, I. Zaripov, Yu. E. Sapozhnikov, I. Vikhareva","doi":"10.15828/2075-8545-2021-13-6-358-364","DOIUrl":"https://doi.org/10.15828/2075-8545-2021-13-6-358-364","url":null,"abstract":"","PeriodicalId":43938,"journal":{"name":"Nanotechnologies in Construction-A Scientific Internet-Journal","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2021-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83782150","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 : 2021-12-22DOI: 10.15828/2075-8545-2021-13-6-379-385
G. Aminova, A. Mašková, G. Yarmukhametova, N. Gareeva, A. Mazitova
Introduction. The increase in production volumes and the expansion of the scope of application of polyvinyl chloride (PVC) compounds contributes to the development of new additives and the attraction of new sources of raw materials for their production. The most important additives necessary for processing PVC are plasticizers. Plasticizers market is one of the largest segments of the global additives market. Since plasticizers are the most simple, cheap and affordable way to modify various properties of the polymeric compositions, their role in processing polymeric materials has recently increased significantly. In application the ester plasticizers, capable to plasticize almost all polymers, especially polyvinylchloride are considered as the most practical. Currently, the industry has mastered production of more than three hundred brands of plasticizers, most of which are esters of phthalic acid. Traditional phthalate plasticizers are the most widely used all over the world. Materials and methods. The paper describes the esterification reactions of phthalic anhydride with oxyethylated (degree of oxyethylation 1.2) and oxypropylated (degree of oxypropelation 1.1) cresols. New symmetric and asymmetric phthalate plasticizers were obtained – dikresoxycresylphthalate, butoxyethylcreoxyethylphthalate, cresylcresoxyethylphthalate and cresylcresoxypropylphthalate, optimum conditions for their preparationare picked up, studied their physical and chemical properties. The obtained experimental data were used to identify promising new phthalate-type plasticizers by the method of cluster analysis. Cluster analysis is the most effective method for solving this problem, because it is intended for combining some samples into classes (clusters) in such a way that the most similar in properties fall into one cluster, but at the same time the samples of different clusters differ as much as possible from each other. Clustering was carried out using the Statistica 10 program. Since at present the reference plasticizer is dioctylphthalate (DOP), the test results of the samples were compared with those of PVC compositions containing DOP. Results and discussions. According to the data obtained, it was found that butoxyethylcreoxyethyl phthalate has the best characteristics in terms of plasticizing ability. The influence of the selected plasticizer on the technological characteristics of PVC-compounds has been studied. The efficiency of the synthesized butoxyethylcreoxyethylphthalate in the PVC composition was evaluated by the indicator (index) of melt flow rate (MFR) and by the indicators of “thermal stability” and “color stability”. Conclusion. Use of the developed additive contributes to the production of PVC compounds with improved rheological characteristics, increased heat resistance and color stability.
{"title":"Obtaining new phthalate plasticizers","authors":"G. Aminova, A. Mašková, G. Yarmukhametova, N. Gareeva, A. Mazitova","doi":"10.15828/2075-8545-2021-13-6-379-385","DOIUrl":"https://doi.org/10.15828/2075-8545-2021-13-6-379-385","url":null,"abstract":"Introduction. The increase in production volumes and the expansion of the scope of application of polyvinyl chloride (PVC) compounds contributes to the development of new additives and the attraction of new sources of raw materials for their production. The most important additives necessary for processing PVC are plasticizers. Plasticizers market is one of the largest segments of the global additives market. Since plasticizers are the most simple, cheap and affordable way to modify various properties of the polymeric compositions, their role in processing polymeric materials has recently increased significantly. In application the ester plasticizers, capable to plasticize almost all polymers, especially polyvinylchloride are considered as the most practical. Currently, the industry has mastered production of more than three hundred brands of plasticizers, most of which are esters of phthalic acid. Traditional phthalate plasticizers are the most widely used all over the world. Materials and methods. The paper describes the esterification reactions of phthalic anhydride with oxyethylated (degree of oxyethylation 1.2) and oxypropylated (degree of oxypropelation 1.1) cresols. New symmetric and asymmetric phthalate plasticizers were obtained – dikresoxycresylphthalate, butoxyethylcreoxyethylphthalate, cresylcresoxyethylphthalate and cresylcresoxypropylphthalate, optimum conditions for their preparationare picked up, studied their physical and chemical properties. The obtained experimental data were used to identify promising new phthalate-type plasticizers by the method of cluster analysis. Cluster analysis is the most effective method for solving this problem, because it is intended for combining some samples into classes (clusters) in such a way that the most similar in properties fall into one cluster, but at the same time the samples of different clusters differ as much as possible from each other. Clustering was carried out using the Statistica 10 program. Since at present the reference plasticizer is dioctylphthalate (DOP), the test results of the samples were compared with those of PVC compositions containing DOP. Results and discussions. According to the data obtained, it was found that butoxyethylcreoxyethyl phthalate has the best characteristics in terms of plasticizing ability. The influence of the selected plasticizer on the technological characteristics of PVC-compounds has been studied. The efficiency of the synthesized butoxyethylcreoxyethylphthalate in the PVC composition was evaluated by the indicator (index) of melt flow rate (MFR) and by the indicators of “thermal stability” and “color stability”. Conclusion. Use of the developed additive contributes to the production of PVC compounds with improved rheological characteristics, increased heat resistance and color stability.","PeriodicalId":43938,"journal":{"name":"Nanotechnologies in Construction-A Scientific Internet-Journal","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2021-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81780569","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 : 2021-10-30DOI: 10.15828/2075-8545-2021-13-5-276-281
A. Ayzenshtadt, V. Danilov, T. Drozdyuk, M. Frolova, G. Garamov
{"title":"Integral quality indicators of waste concrete for reuse","authors":"A. Ayzenshtadt, V. Danilov, T. Drozdyuk, M. Frolova, G. Garamov","doi":"10.15828/2075-8545-2021-13-5-276-281","DOIUrl":"https://doi.org/10.15828/2075-8545-2021-13-5-276-281","url":null,"abstract":"","PeriodicalId":43938,"journal":{"name":"Nanotechnologies in Construction-A Scientific Internet-Journal","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2021-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90517519","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 : 2021-10-30DOI: 10.15828/2075-8545-2021-13-5-282-292
B. Gusev, Samuel Y. L. Yin, A. Speransky
{"title":"Arrangement of chemical elements in the three-dimensional matrix","authors":"B. Gusev, Samuel Y. L. Yin, A. Speransky","doi":"10.15828/2075-8545-2021-13-5-282-292","DOIUrl":"https://doi.org/10.15828/2075-8545-2021-13-5-282-292","url":null,"abstract":"","PeriodicalId":43938,"journal":{"name":"Nanotechnologies in Construction-A Scientific Internet-Journal","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2021-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88191205","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 : 2021-10-30DOI: 10.15828/2075-8545-2021-13-5-293-305
A. Maher, M. El-Feky, Alaa Mohsen, M. Kohail
{"title":"Properties of Nano Engineered Concrete Subjected to Accelerated Corrosion","authors":"A. Maher, M. El-Feky, Alaa Mohsen, M. Kohail","doi":"10.15828/2075-8545-2021-13-5-293-305","DOIUrl":"https://doi.org/10.15828/2075-8545-2021-13-5-293-305","url":null,"abstract":"","PeriodicalId":43938,"journal":{"name":"Nanotechnologies in Construction-A Scientific Internet-Journal","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2021-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77529353","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 : 2021-10-30DOI: 10.15828/2075-8545-2021-13-5-319-327
E. Boev, A. Islamutdinova, E. Aminova
{"title":"Obtaining the retainer for waterproofing road bitumens","authors":"E. Boev, A. Islamutdinova, E. Aminova","doi":"10.15828/2075-8545-2021-13-5-319-327","DOIUrl":"https://doi.org/10.15828/2075-8545-2021-13-5-319-327","url":null,"abstract":"","PeriodicalId":43938,"journal":{"name":"Nanotechnologies in Construction-A Scientific Internet-Journal","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2021-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74480625","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 : 2021-08-31DOI: 10.15828/2075-8545-2021-13-4-259-263
D. Gura, D. Bespyatchuk, S. Samarin, N. Kiryunikova, E. Lesovaya
{"title":"Technology of three-dimensional laser scanning as a tool to provide safety for sport facilities","authors":"D. Gura, D. Bespyatchuk, S. Samarin, N. Kiryunikova, E. Lesovaya","doi":"10.15828/2075-8545-2021-13-4-259-263","DOIUrl":"https://doi.org/10.15828/2075-8545-2021-13-4-259-263","url":null,"abstract":"","PeriodicalId":43938,"journal":{"name":"Nanotechnologies in Construction-A Scientific Internet-Journal","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79131415","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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