S. Panin, I. Vlasov, D. Dudina, V. Ulyanitsky, R. Stankevich, I. Batraev, P. Maruschak, M. Landová
Abstract The structure and mechanical properties of the coatings formed by reactive detonation spraying of titanium in a wide range of spraying conditions were studied. The variable deposition parameters were the nature of the carrier gas, the spraying distance, the O2/C2H2 ratio, and the volume of the explosive mixture. The phase composition of the coatings and the influence of the spraying parameters on the mechanical properties of the coatings were investigated. In addition, nanohardness of the individual phases contained the coatings was evaluated. It was found that the composition of the strengthening phases in the coatings depends on the O2/C2H2 ratio and the nature of the carrier gas. Detonation spraying conditions ensuring the formation of composite coatings with a set of improved mechanical properties are discussed.
{"title":"Deposition of titanium based coatings by reactive detonation spraying","authors":"S. Panin, I. Vlasov, D. Dudina, V. Ulyanitsky, R. Stankevich, I. Batraev, P. Maruschak, M. Landová","doi":"10.2478/kom-2018-0002","DOIUrl":"https://doi.org/10.2478/kom-2018-0002","url":null,"abstract":"Abstract The structure and mechanical properties of the coatings formed by reactive detonation spraying of titanium in a wide range of spraying conditions were studied. The variable deposition parameters were the nature of the carrier gas, the spraying distance, the O2/C2H2 ratio, and the volume of the explosive mixture. The phase composition of the coatings and the influence of the spraying parameters on the mechanical properties of the coatings were investigated. In addition, nanohardness of the individual phases contained the coatings was evaluated. It was found that the composition of the strengthening phases in the coatings depends on the O2/C2H2 ratio and the nature of the carrier gas. Detonation spraying conditions ensuring the formation of composite coatings with a set of improved mechanical properties are discussed.","PeriodicalId":17911,"journal":{"name":"Koroze a ochrana materialu","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46398939","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 Within the national and international research program of materials for advanced nuclear reactors Czech organizations contributed with several tests of metallic alloys. The specimens of the alloys were first exposed in the long term (up to 1500 hours) in simulated advanced gas cooled reactor coolant environment at 750-900 °C. After exposure the degradation of tested materials was explored, especially changes in material microstructure, corrosion damage and corrosion layer composition and in some cases also changes in mechanical properties were observed. In this paper selected results of exposure tests in high temperature helium of alloy 800 H, austenitic steel 316L and high-temperature nickel alloys are presented.
{"title":"High temperature alloys stability testing in impure helium","authors":"J. Berka, D. Marušáková, J. Kalivodová","doi":"10.2478/kom-2018-0004","DOIUrl":"https://doi.org/10.2478/kom-2018-0004","url":null,"abstract":"Abstract Within the national and international research program of materials for advanced nuclear reactors Czech organizations contributed with several tests of metallic alloys. The specimens of the alloys were first exposed in the long term (up to 1500 hours) in simulated advanced gas cooled reactor coolant environment at 750-900 °C. After exposure the degradation of tested materials was explored, especially changes in material microstructure, corrosion damage and corrosion layer composition and in some cases also changes in mechanical properties were observed. In this paper selected results of exposure tests in high temperature helium of alloy 800 H, austenitic steel 316L and high-temperature nickel alloys are presented.","PeriodicalId":17911,"journal":{"name":"Koroze a ochrana materialu","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49154443","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 contribution is focused on the preparation of coating based on the dicalcium phosphate-dihydrate (DCPD) on the surface of ZW3 magnesium alloy. For the preparation of the coating a cathodic electrodeposition technique called Large Amplitude Sinusoidal Voltammetry (LASV) was used. The DCPD layer was prepared at the temperature of 22 ± 2 °C in electrolyte composed of 0.1M Ca(NO3).4H2O, 0.06 M NH4H2PO4 and H2O2. Electrochemical characteristics were evaluated by electrochemical impedance spectroscopy (EIS) in 0.1M NaCl solution. The obtained data in form of Nyquist plots were analysed by the equivalent circuit method. It is clear from the measured values of polarization resistance Rp that dicalcium phosphate-dihydrate (DCPD) layer prepared by LASV electro-deposition technique improved corrosion resistance of ZW3 alloy in the chosen environment.
{"title":"Evolution of the dicalcium phosphate-dihydrate (DCPD) coating created by large amplitude sinusoidal voltammetry (LASV) on corrosion resistance of the ZW3 magnesium alloy in chloride containing environment","authors":"D. Kajánek, B. Hadzima, F. Pastorek, M. Jacková","doi":"10.2478/kom-2018-0003","DOIUrl":"https://doi.org/10.2478/kom-2018-0003","url":null,"abstract":"Abstract The contribution is focused on the preparation of coating based on the dicalcium phosphate-dihydrate (DCPD) on the surface of ZW3 magnesium alloy. For the preparation of the coating a cathodic electrodeposition technique called Large Amplitude Sinusoidal Voltammetry (LASV) was used. The DCPD layer was prepared at the temperature of 22 ± 2 °C in electrolyte composed of 0.1M Ca(NO3).4H2O, 0.06 M NH4H2PO4 and H2O2. Electrochemical characteristics were evaluated by electrochemical impedance spectroscopy (EIS) in 0.1M NaCl solution. The obtained data in form of Nyquist plots were analysed by the equivalent circuit method. It is clear from the measured values of polarization resistance Rp that dicalcium phosphate-dihydrate (DCPD) layer prepared by LASV electro-deposition technique improved corrosion resistance of ZW3 alloy in the chosen environment.","PeriodicalId":17911,"journal":{"name":"Koroze a ochrana materialu","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44319278","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. Knotek, P. Korandová, R. Kalousková, M. Ďurovič
Abstract Most of the cinematographic film collections stored in film archives are made on a triacetate base, and from the 1950s to the 1980s, a magnetic track was used to record sound. With a large number of archive materials, archives often do not know the chemical composition of film bases, history of use and degradation rates. Therefore, the chemical composition of three films with a magnetic audio track and one representative of the modern film FOMAPAN were investigated by infrared spectroscopy. Selected samples were artificially aged at elevated temperatures and humidity, and the rate of degradation of the film was evaluated by infrared spectroscopy, dimensional changes and gravimetric analysis. Based on the measurements, all of the examined films were made from cellulose triacetate and the binder of the magnetic trackswas cellulose nitrate. To determine the degree of degradation of the binder of the audio track and the triacetate base, a degradation index was created which expresses the ratio of the bandwidths of the characteristic groups in the infrared spectra. It is shown that infrared spectroscopy makes it easy to determine the chemical composition of cinematographic films and to quantify the rate of degradation and the current state of the film base using a suitably chosen degradation index.
{"title":"Study of triacetate cinematographic films and magnetic audio track by infrared spectroscopy","authors":"V. Knotek, P. Korandová, R. Kalousková, M. Ďurovič","doi":"10.2478/kom-2018-0005","DOIUrl":"https://doi.org/10.2478/kom-2018-0005","url":null,"abstract":"Abstract Most of the cinematographic film collections stored in film archives are made on a triacetate base, and from the 1950s to the 1980s, a magnetic track was used to record sound. With a large number of archive materials, archives often do not know the chemical composition of film bases, history of use and degradation rates. Therefore, the chemical composition of three films with a magnetic audio track and one representative of the modern film FOMAPAN were investigated by infrared spectroscopy. Selected samples were artificially aged at elevated temperatures and humidity, and the rate of degradation of the film was evaluated by infrared spectroscopy, dimensional changes and gravimetric analysis. Based on the measurements, all of the examined films were made from cellulose triacetate and the binder of the magnetic trackswas cellulose nitrate. To determine the degree of degradation of the binder of the audio track and the triacetate base, a degradation index was created which expresses the ratio of the bandwidths of the characteristic groups in the infrared spectra. It is shown that infrared spectroscopy makes it easy to determine the chemical composition of cinematographic films and to quantify the rate of degradation and the current state of the film base using a suitably chosen degradation index.","PeriodicalId":17911,"journal":{"name":"Koroze a ochrana materialu","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48634347","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 High entropy alloys (HEAs) have been in focus of scientist for past few years owing to their predicted scratch, corrosion and temperature resistance and also to interesting magnetic properties. They are usually prepared by arc melting of at least 5 pure elements. This article deals with electrodeposition of such five-element alloy from water bath, which have not been yet reported. The HEA coating consisting of Fe, Co, Ni, Mn and Mo or Zn was successfully electrodeposited on steel, copper and other metallic substrates. Substrates were polished and treated by sonication in acetone prior to electrodeposition. Obtained thin layers were documented by optical microscopy and SEM techniques. Their exact composition was determined by EDS and XRF analysis. Scratch and accelerated corrosion tests were performed to asses their resistance properties. Electrochemical properties were determined by measurements of polarization curves.
{"title":"Electrodeposition of high entropy alloy coating from water bath","authors":"J. Bárta, S. Ivanova, M. Pazderová","doi":"10.2478/kom-2018-0001","DOIUrl":"https://doi.org/10.2478/kom-2018-0001","url":null,"abstract":"Abstract High entropy alloys (HEAs) have been in focus of scientist for past few years owing to their predicted scratch, corrosion and temperature resistance and also to interesting magnetic properties. They are usually prepared by arc melting of at least 5 pure elements. This article deals with electrodeposition of such five-element alloy from water bath, which have not been yet reported. The HEA coating consisting of Fe, Co, Ni, Mn and Mo or Zn was successfully electrodeposited on steel, copper and other metallic substrates. Substrates were polished and treated by sonication in acetone prior to electrodeposition. Obtained thin layers were documented by optical microscopy and SEM techniques. Their exact composition was determined by EDS and XRF analysis. Scratch and accelerated corrosion tests were performed to asses their resistance properties. Electrochemical properties were determined by measurements of polarization curves.","PeriodicalId":17911,"journal":{"name":"Koroze a ochrana materialu","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45435114","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}
L. Poberezhny, P. Maruschak, A. Hrytsanchuk, B. Mischuk, D. Draganovská, L. Poberezhna
Abstract Vliv střídavého indukovaného proudu na korozní rychlost oceli St3 a 17GS byl pozorován v simulovaných půdních elektrolytech typických pro Ukrajinu. Ocel St3 je citlivější na přirozené korozní napadení v půdě i na napadení vyvolané střídavým proudem. Byla stanovena nejhorší prostředí z hlediska koroze v elektrolytech obsahujících chloridy či směs chloridů se sírany.
{"title":"Impact of AC Current Density on Material Corrosion of Distribution Pipelines","authors":"L. Poberezhny, P. Maruschak, A. Hrytsanchuk, B. Mischuk, D. Draganovská, L. Poberezhna","doi":"10.1515/kom-2017-0023","DOIUrl":"https://doi.org/10.1515/kom-2017-0023","url":null,"abstract":"Abstract Vliv střídavého indukovaného proudu na korozní rychlost oceli St3 a 17GS byl pozorován v simulovaných půdních elektrolytech typických pro Ukrajinu. Ocel St3 je citlivější na přirozené korozní napadení v půdě i na napadení vyvolané střídavým proudem. Byla stanovena nejhorší prostředí z hlediska koroze v elektrolytech obsahujících chloridy či směs chloridů se sírany.","PeriodicalId":17911,"journal":{"name":"Koroze a ochrana materialu","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/kom-2017-0023","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43681231","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. Prehradná, L. Rozumová, F. Di Gabriele, M. Chocholoušek, V. Dostál
Abstract This paper deals with the behavior of the ferritic-martensitic steel T91 samples covered with an AlTiN black coating, which is mainly used for high temperature applications (> 800 ° C) because of its resistance to oxidation. The coating was applied by use of a combination of High Power Impulse Magnetron Sputtering (HiPIMS) and Direct Current Magnetron Sputtering (DCMS). Samples were subjected to a tensile test in a static tank CALLISTO. The environment was liquid PbBi eutectic at a temperature of 550° C. Two types of samples, with a notch in the middle and without a notch, were tested. After exposure, the samples were subjected to morphological and chemical analyzes on SEM and EDX. Although the coating cracked over the entire length of the sample, high adhesion of the layer was demonstrated, the coating was delaminated locally only in the notch.
{"title":"Analysis of the Coating for Heavy Liquid Metal Applications","authors":"J. Prehradná, L. Rozumová, F. Di Gabriele, M. Chocholoušek, V. Dostál","doi":"10.1515/kom-2017-0022","DOIUrl":"https://doi.org/10.1515/kom-2017-0022","url":null,"abstract":"Abstract This paper deals with the behavior of the ferritic-martensitic steel T91 samples covered with an AlTiN black coating, which is mainly used for high temperature applications (> 800 ° C) because of its resistance to oxidation. The coating was applied by use of a combination of High Power Impulse Magnetron Sputtering (HiPIMS) and Direct Current Magnetron Sputtering (DCMS). Samples were subjected to a tensile test in a static tank CALLISTO. The environment was liquid PbBi eutectic at a temperature of 550° C. Two types of samples, with a notch in the middle and without a notch, were tested. After exposure, the samples were subjected to morphological and chemical analyzes on SEM and EDX. Although the coating cracked over the entire length of the sample, high adhesion of the layer was demonstrated, the coating was delaminated locally only in the notch.","PeriodicalId":17911,"journal":{"name":"Koroze a ochrana materialu","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49400528","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 Nowadays a large number of mechanical surface treatments of constructions materials is used in industry, mainly focusing on steel surface treatment. The aim of this study was to evaluate the effects of mechanical surface pre-treatment (grinding and shot peening) on corrosion resistance of high strength low alloy Domex 700 steel. Suitable mechanical surface treatment can by used for surface homogenization (eg. grinding) or for improvement of mechanical, strength and fatigue properties (shot peening). 0,1M NaCl solution of ambient temperature was used as an environment for electrochemical tests. Evaluation of the mechanical surface treatment effect on corrosion resistance of Domex 700 steel surface was realized by electrochemical tests: potentiodynamic polarization tests (using Tafel analysis) and electrochemical impedance spectroscopy (using equivalent circuit). From the obtained results it is possible to conclude, that the process of mechanical surface treatment by shot peening at choosen conditions has negative effect on corrosion resistance of Domex 700 steel.
{"title":"Electrochemical Corrosion Characteristics of High Strength Low Alloy Domex 700 Steel After Mechanical Surface Treatment in Chloride Environment","authors":"K. Borko, F. Pastorek, B. Hadzima","doi":"10.1515/kom-2017-0020","DOIUrl":"https://doi.org/10.1515/kom-2017-0020","url":null,"abstract":"Abstract Nowadays a large number of mechanical surface treatments of constructions materials is used in industry, mainly focusing on steel surface treatment. The aim of this study was to evaluate the effects of mechanical surface pre-treatment (grinding and shot peening) on corrosion resistance of high strength low alloy Domex 700 steel. Suitable mechanical surface treatment can by used for surface homogenization (eg. grinding) or for improvement of mechanical, strength and fatigue properties (shot peening). 0,1M NaCl solution of ambient temperature was used as an environment for electrochemical tests. Evaluation of the mechanical surface treatment effect on corrosion resistance of Domex 700 steel surface was realized by electrochemical tests: potentiodynamic polarization tests (using Tafel analysis) and electrochemical impedance spectroscopy (using equivalent circuit). From the obtained results it is possible to conclude, that the process of mechanical surface treatment by shot peening at choosen conditions has negative effect on corrosion resistance of Domex 700 steel.","PeriodicalId":17911,"journal":{"name":"Koroze a ochrana materialu","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/kom-2017-0020","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41453978","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}
A. Krausová, L. Tůma, M. Novak, L. Cvrček, J. Krejčí, J. Macák
Abstract Increasing of nuclear safety, higher demands for longer nuclear fuel campaign and higher levels of burnout are based on improving the properties of zirconium alloys. Protective coatings appears to be a promising way to reduce their chemical reactivity and increase resistance to hydriding. In this work, a thin chromium coating applied to a standard Zr1Nb zirconium alloy was studied using in-situ impedance spectroscopy. Exposure was carried out at a temperature of 280 ° C and a pressure of 8 MPa in a simulated WWER primary coolant environment. The results show that the chromium-coated Zr1Nb alloy is under these conditions oxidized significantly slower than the non-coated alloy.
{"title":"Chromium Coating as a Surface Protection of Zirconium Alloys","authors":"A. Krausová, L. Tůma, M. Novak, L. Cvrček, J. Krejčí, J. Macák","doi":"10.1515/kom-2017-0021","DOIUrl":"https://doi.org/10.1515/kom-2017-0021","url":null,"abstract":"Abstract Increasing of nuclear safety, higher demands for longer nuclear fuel campaign and higher levels of burnout are based on improving the properties of zirconium alloys. Protective coatings appears to be a promising way to reduce their chemical reactivity and increase resistance to hydriding. In this work, a thin chromium coating applied to a standard Zr1Nb zirconium alloy was studied using in-situ impedance spectroscopy. Exposure was carried out at a temperature of 280 ° C and a pressure of 8 MPa in a simulated WWER primary coolant environment. The results show that the chromium-coated Zr1Nb alloy is under these conditions oxidized significantly slower than the non-coated alloy.","PeriodicalId":17911,"journal":{"name":"Koroze a ochrana materialu","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47467475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract This paper describes behaviour of the ferritic-martensitic steel T91 after long-term exposure in liquid eutectic PbBi. Small specimens of the steel were pre-loaded according to the ISO Standard No. 7539-2 and subsequently exposed to PbBi. The experiment was carried out in a flowing and static liquid metal medium at 350°C. The experimental time was selected for the flowing environment at 1000 hours and for static environment at 2000 hours. After exposure, the specimens were analysed by use SEM and EDX. Surface changes of the specimens from different experimental conditions were compared and discussed. The initiation of the cracks wasn´t observed in the monitored expositions.
{"title":"Analysis of resistance of T91 steel under load in liquid PbBi","authors":"L. Rozumová, F. Di Gabriele, A. Hojná","doi":"10.1515/kom-2017-0024","DOIUrl":"https://doi.org/10.1515/kom-2017-0024","url":null,"abstract":"Abstract This paper describes behaviour of the ferritic-martensitic steel T91 after long-term exposure in liquid eutectic PbBi. Small specimens of the steel were pre-loaded according to the ISO Standard No. 7539-2 and subsequently exposed to PbBi. The experiment was carried out in a flowing and static liquid metal medium at 350°C. The experimental time was selected for the flowing environment at 1000 hours and for static environment at 2000 hours. After exposure, the specimens were analysed by use SEM and EDX. Surface changes of the specimens from different experimental conditions were compared and discussed. The initiation of the cracks wasn´t observed in the monitored expositions.","PeriodicalId":17911,"journal":{"name":"Koroze a ochrana materialu","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47598066","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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