Pub Date : 1997-01-01DOI: 10.2473/SHIGENTOSOZAI.113.601
T. Imai, I. Nakajima, K. Asakura, T. Goto
The purpose of this study is to prove the effect of internal pore pressure on unsteady-state gas flow in coal. Practically, the gas permeation model of coal which consists of the gas permeable and non-permeable crack network was proposed. Then the numerical simulations of gas permeation by this model were carried out by changing the parameters such as inlet pressure in the crack network, confining pressure against coal, closing probability of cracks, etc.The results of these simulations on fluctuations of unsteady-state gas flow were in agreements with the experiments of gas permeation of coal. From these considerations it was found that the above gas permeation model was accurate enough for practically. Moreover, the results of the simulations on unsteady-state gas flow in coal gave an explanation to the deviation from the Darcy's law in the relationsbetween gas flow and difference pressure.
{"title":"Effect of Internal Gas Pressure on Gas Permeability of Coal in Unsteady-State Gas Flow. Study on gas permeability of coal by crack network model (2nd Report).","authors":"T. Imai, I. Nakajima, K. Asakura, T. Goto","doi":"10.2473/SHIGENTOSOZAI.113.601","DOIUrl":"https://doi.org/10.2473/SHIGENTOSOZAI.113.601","url":null,"abstract":"The purpose of this study is to prove the effect of internal pore pressure on unsteady-state gas flow in coal. Practically, the gas permeation model of coal which consists of the gas permeable and non-permeable crack network was proposed. Then the numerical simulations of gas permeation by this model were carried out by changing the parameters such as inlet pressure in the crack network, confining pressure against coal, closing probability of cracks, etc.The results of these simulations on fluctuations of unsteady-state gas flow were in agreements with the experiments of gas permeation of coal. From these considerations it was found that the above gas permeation model was accurate enough for practically. Moreover, the results of the simulations on unsteady-state gas flow in coal gave an explanation to the deviation from the Darcy's law in the relationsbetween gas flow and difference pressure.","PeriodicalId":22754,"journal":{"name":"The Mining and Materials Processing Institute of Japan","volume":"6 1","pages":"601-607"},"PeriodicalIF":0.0,"publicationDate":"1997-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87503721","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 : 1997-01-01DOI: 10.2473/SHIGENTOSOZAI.113.593
T. Goto, J. Kodama, K. Itakura, Y. Yoshida
Deformation rate analysis (DRA), although it has a poor theoretical basis, is a useful method for estimating rock stress in the laboratory using core samples. DRA is thought to be closely related to changes in the inner microstructure of rock samples undergoing a de formation process. Ultrasonic measurement is a useful technique for investigating structural changes in rocks. In this study, both methods were applied simultaneously to rock samples to confirm the applicability of ultrasonic measurement for the estimation of rock stress using a system of ultrasonic propagation time with accuracy in 10-2 nsec.In the experiments, core samples of sandstone were loaded up to a certain stress in order to artificially input memory of the stress into the samples, and the propagation time in the horizontal direction to the loading axis and the deformation rate were measured simultaneously. Consequently, the propagation time through the specimen was measured with high accuracy during deformation. Variations in the propagation time and lateral strain almost coincided during the loading-up process. Furthermore, the propagation time was drastically changed at the memorized stress corresponding to the deflection point of the deformation rate curve. These experimental results show that highly accurate measurement of the ultrasonic propagation time is useful, as is the DRA method using core samples, for examining changes in the microstructure inside rock samples under stress and applicable for estimating underground rock stress.
{"title":"Application of the Ultrasonic Propagation Time of a Core Sample for Stress Measurement of Underground Rocks.","authors":"T. Goto, J. Kodama, K. Itakura, Y. Yoshida","doi":"10.2473/SHIGENTOSOZAI.113.593","DOIUrl":"https://doi.org/10.2473/SHIGENTOSOZAI.113.593","url":null,"abstract":"Deformation rate analysis (DRA), although it has a poor theoretical basis, is a useful method for estimating rock stress in the laboratory using core samples. DRA is thought to be closely related to changes in the inner microstructure of rock samples undergoing a de formation process. Ultrasonic measurement is a useful technique for investigating structural changes in rocks. In this study, both methods were applied simultaneously to rock samples to confirm the applicability of ultrasonic measurement for the estimation of rock stress using a system of ultrasonic propagation time with accuracy in 10-2 nsec.In the experiments, core samples of sandstone were loaded up to a certain stress in order to artificially input memory of the stress into the samples, and the propagation time in the horizontal direction to the loading axis and the deformation rate were measured simultaneously. Consequently, the propagation time through the specimen was measured with high accuracy during deformation. Variations in the propagation time and lateral strain almost coincided during the loading-up process. Furthermore, the propagation time was drastically changed at the memorized stress corresponding to the deflection point of the deformation rate curve. These experimental results show that highly accurate measurement of the ultrasonic propagation time is useful, as is the DRA method using core samples, for examining changes in the microstructure inside rock samples under stress and applicable for estimating underground rock stress.","PeriodicalId":22754,"journal":{"name":"The Mining and Materials Processing Institute of Japan","volume":"17 1","pages":"593-599"},"PeriodicalIF":0.0,"publicationDate":"1997-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86222395","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 : 1997-01-01DOI: 10.2473/SHIGENTOSOZAI.113.205
T. Tanabe, Z. Asaki
For the development of lead-free solder, wettability of 41.2Sn-58.8Bi and 61.6Sn-38.4Pb solders was compared by use of meniscometer. It has been reported by several researchers that the wettability of Sn-Bi solder is poor as compared with Sn-Pb solder. In order to obtain fundamental data, no flux was used in this work because wettability of solder is significantly affected by the kind of flux and the available fluxes have been developed for Sn-Pb solder. Oxygen-free copper plate and copper alloy plate containing 0.3 mass % Cr, 0.1 mass % Zr and 0.02 mass % Si of 0.5mm in thickness and 10mm wide were immersed into the molten solders at the temperature range from 483 K to 543 K. It was found that wettability of both Sn-Bi and Sn-Pb solders to these plates was poor without use of flux. Then a parameter (surface tension) by cosine (contact angle) was used for the comparison of wettability of these solders. No significant difference in the parameter between these solders was observed. Consequently, it is thought that the Sn-Bi solder will be promising provided that flux suitable for this solder is developed.
{"title":"Wettability of Cu Plate by a Sn-Bi Solder.","authors":"T. Tanabe, Z. Asaki","doi":"10.2473/SHIGENTOSOZAI.113.205","DOIUrl":"https://doi.org/10.2473/SHIGENTOSOZAI.113.205","url":null,"abstract":"For the development of lead-free solder, wettability of 41.2Sn-58.8Bi and 61.6Sn-38.4Pb solders was compared by use of meniscometer. It has been reported by several researchers that the wettability of Sn-Bi solder is poor as compared with Sn-Pb solder. In order to obtain fundamental data, no flux was used in this work because wettability of solder is significantly affected by the kind of flux and the available fluxes have been developed for Sn-Pb solder. Oxygen-free copper plate and copper alloy plate containing 0.3 mass % Cr, 0.1 mass % Zr and 0.02 mass % Si of 0.5mm in thickness and 10mm wide were immersed into the molten solders at the temperature range from 483 K to 543 K. It was found that wettability of both Sn-Bi and Sn-Pb solders to these plates was poor without use of flux. Then a parameter (surface tension) by cosine (contact angle) was used for the comparison of wettability of these solders. No significant difference in the parameter between these solders was observed. Consequently, it is thought that the Sn-Bi solder will be promising provided that flux suitable for this solder is developed.","PeriodicalId":22754,"journal":{"name":"The Mining and Materials Processing Institute of Japan","volume":"6 1","pages":"205-209"},"PeriodicalIF":0.0,"publicationDate":"1997-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83676422","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 : 1997-01-01DOI: 10.2473/shigentosozai.113.631
Ezequiel Cruz Sanchez, Yoshiaki Umetsc, F. Saito
Leaching of chalcopyrite concentrate having specific surface area of about 3 m2/g in 0.5 mol/dm3 HCl solution was conducted at 333 K using hematite (Fe2O3) and ferric chloride (FeCl3) powders, respectively. The leaching of the concentrate with Fe2O3 powder permits to achieve about 75 % copperextraction within 24 hours, while about 65 % copper is extracted by the leaching with FeCl3 powder. Theyield of copper in the leaching with Fe2O3 powder is twice or more higher than that without the promoters. High copper extraction can be achieved when much of the elemental sulfur is formed on thesolid residue after the leaching. Especially, the presence of Fe2O3 powder gives us the elemental sulfurprecipitates more than that of FeCl3 powder. Therefore, Fe2O3 can be an effective promoter inthe leaching of chalcopyrite concentrate using HCl solution.
{"title":"Acid Leaching of Chalcopyrite Concentrate with Hematite Powder as an Effective Promoter.","authors":"Ezequiel Cruz Sanchez, Yoshiaki Umetsc, F. Saito","doi":"10.2473/shigentosozai.113.631","DOIUrl":"https://doi.org/10.2473/shigentosozai.113.631","url":null,"abstract":"Leaching of chalcopyrite concentrate having specific surface area of about 3 m2/g in 0.5 mol/dm3 HCl solution was conducted at 333 K using hematite (Fe2O3) and ferric chloride (FeCl3) powders, respectively. The leaching of the concentrate with Fe2O3 powder permits to achieve about 75 % copperextraction within 24 hours, while about 65 % copper is extracted by the leaching with FeCl3 powder. Theyield of copper in the leaching with Fe2O3 powder is twice or more higher than that without the promoters. High copper extraction can be achieved when much of the elemental sulfur is formed on thesolid residue after the leaching. Especially, the presence of Fe2O3 powder gives us the elemental sulfurprecipitates more than that of FeCl3 powder. Therefore, Fe2O3 can be an effective promoter inthe leaching of chalcopyrite concentrate using HCl solution.","PeriodicalId":22754,"journal":{"name":"The Mining and Materials Processing Institute of Japan","volume":"23 1","pages":"631-634"},"PeriodicalIF":0.0,"publicationDate":"1997-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82928207","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 : 1997-01-01DOI: 10.2473/SHIGENTOSOZAI.113.768
T. Yuasa
{"title":"Project for Stable Overseas Coal Supply.","authors":"T. Yuasa","doi":"10.2473/SHIGENTOSOZAI.113.768","DOIUrl":"https://doi.org/10.2473/SHIGENTOSOZAI.113.768","url":null,"abstract":"","PeriodicalId":22754,"journal":{"name":"The Mining and Materials Processing Institute of Japan","volume":"20 1","pages":"768-771"},"PeriodicalIF":0.0,"publicationDate":"1997-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79272659","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 : 1997-01-01DOI: 10.2473/SHIGENTOSOZAI.113.738
H. Mirabediny
{"title":"Development of Mining Cost Data Base System.","authors":"H. Mirabediny","doi":"10.2473/SHIGENTOSOZAI.113.738","DOIUrl":"https://doi.org/10.2473/SHIGENTOSOZAI.113.738","url":null,"abstract":"","PeriodicalId":22754,"journal":{"name":"The Mining and Materials Processing Institute of Japan","volume":"83 1","pages":"738-741"},"PeriodicalIF":0.0,"publicationDate":"1997-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90690121","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 : 1997-01-01DOI: 10.2473/SHIGENTOSOZAI.113.1115
Kenta Tabuchi, S. Kawakami, T. Shiratori, T. Saitoh
Soil washing treatment is a water based process for mechanically scrubbing soils ex situ to remove undesirable contaminants. The process remove contaminants by dissolving or suspending them in wash solution or by concentrating them into a smaller volume of soil through particle size separation techniques. This process together with biological treatment is relatively mild to soil nature compared thermal treatment, so adequate for recycling of soil.The concept of reducing contamination through the use of particle size separation is based on the finding that most inorganic or organic contaminants tend to bind to clay and silt soil particles. Washing processes that separate the clay and silt particles from sand and gravel soil particles effectively separate and concentrate the contaminants into a smaller volume of soil that can be further treated or disposed. The clean, larger fraction can be recycled.In this paper, we demonstrate our trials with four types of heavy metal contaminated soil by three methods. Those method are a laboratory size separation experiment, a pilot plant experiment and a full scale plant treatment.For one type of soil the results of the laboratory experiment were shown to be different from those of the pilot plant experiment. It was suggested that a laboratory test with small volume of soil would make a incorrect estimation for treatability caused by heterogeneity of soil.Another type of soil showed a result that heavy metals exist at higher concentration in coarse particles than fine ones. It was suggested that for this type of soil, simple soil washing treatments are not applicable.A full scale treatment process were shown, and practical quality control were emphasized.
{"title":"Recycling. Soil Recycling from Heavy Metal Contaminated Soil by Soil Washing Treatment.","authors":"Kenta Tabuchi, S. Kawakami, T. Shiratori, T. Saitoh","doi":"10.2473/SHIGENTOSOZAI.113.1115","DOIUrl":"https://doi.org/10.2473/SHIGENTOSOZAI.113.1115","url":null,"abstract":"Soil washing treatment is a water based process for mechanically scrubbing soils ex situ to remove undesirable contaminants. The process remove contaminants by dissolving or suspending them in wash solution or by concentrating them into a smaller volume of soil through particle size separation techniques. This process together with biological treatment is relatively mild to soil nature compared thermal treatment, so adequate for recycling of soil.The concept of reducing contamination through the use of particle size separation is based on the finding that most inorganic or organic contaminants tend to bind to clay and silt soil particles. Washing processes that separate the clay and silt particles from sand and gravel soil particles effectively separate and concentrate the contaminants into a smaller volume of soil that can be further treated or disposed. The clean, larger fraction can be recycled.In this paper, we demonstrate our trials with four types of heavy metal contaminated soil by three methods. Those method are a laboratory size separation experiment, a pilot plant experiment and a full scale plant treatment.For one type of soil the results of the laboratory experiment were shown to be different from those of the pilot plant experiment. It was suggested that a laboratory test with small volume of soil would make a incorrect estimation for treatability caused by heterogeneity of soil.Another type of soil showed a result that heavy metals exist at higher concentration in coarse particles than fine ones. It was suggested that for this type of soil, simple soil washing treatments are not applicable.A full scale treatment process were shown, and practical quality control were emphasized.","PeriodicalId":22754,"journal":{"name":"The Mining and Materials Processing Institute of Japan","volume":"2 1","pages":"1115-1120"},"PeriodicalIF":0.0,"publicationDate":"1997-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90893796","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 : 1997-01-01DOI: 10.2473/shigentosozai.113.859
A. Inoue, M. Kawahara
After leaching cobalt crusts in an ammoniacal solution using sulfur dioxide gas as a reductant, the extraction of cobalt was held down in the solvent extraction process. The effects of sulfite ion on cobalt were studied by using nitroso R salt which forms a complex with cobalt. As a result, formation of cobalt complex salt was negligible in the solution of ammonium sulfite and sodium sulfite. It is supposed that sulfite ion acts as a masking reagent for cobalt.Solvent extraction of cobalt and nickel was carried out using LIX84-I as an extractant for the solution of ammonium sulfite. The effects of the ammonium sulfite concentration and retention time on the extraction of cobalt were investigated. Cobalt (10 ppm) was not extracted from the ammonium sulfite solution of concentration more than 0.5 M and the pH over 10.5. In the same condition, nickel (10 ppm) was extracted completely. Same studies were carried out by using PC-88A and D2EHPA, but superior separation of cobalt and nickel was not attained.An EDTA titration was carried out by addition of sodium sulfite or ammonium sulfite to the solution including cobalt and nickel. As a result, only nickel was titrated quantitatively inthe mixed solution containing up to 1 mg (20 ppm) of cobalt
{"title":"The Masking of Cobalt by Sulfite Ion in Solvent Extraction.","authors":"A. Inoue, M. Kawahara","doi":"10.2473/shigentosozai.113.859","DOIUrl":"https://doi.org/10.2473/shigentosozai.113.859","url":null,"abstract":"After leaching cobalt crusts in an ammoniacal solution using sulfur dioxide gas as a reductant, the extraction of cobalt was held down in the solvent extraction process. The effects of sulfite ion on cobalt were studied by using nitroso R salt which forms a complex with cobalt. As a result, formation of cobalt complex salt was negligible in the solution of ammonium sulfite and sodium sulfite. It is supposed that sulfite ion acts as a masking reagent for cobalt.Solvent extraction of cobalt and nickel was carried out using LIX84-I as an extractant for the solution of ammonium sulfite. The effects of the ammonium sulfite concentration and retention time on the extraction of cobalt were investigated. Cobalt (10 ppm) was not extracted from the ammonium sulfite solution of concentration more than 0.5 M and the pH over 10.5. In the same condition, nickel (10 ppm) was extracted completely. Same studies were carried out by using PC-88A and D2EHPA, but superior separation of cobalt and nickel was not attained.An EDTA titration was carried out by addition of sodium sulfite or ammonium sulfite to the solution including cobalt and nickel. As a result, only nickel was titrated quantitatively inthe mixed solution containing up to 1 mg (20 ppm) of cobalt","PeriodicalId":22754,"journal":{"name":"The Mining and Materials Processing Institute of Japan","volume":"49 1","pages":"859-864"},"PeriodicalIF":0.0,"publicationDate":"1997-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89820181","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 : 1997-01-01DOI: 10.2473/SHIGENTOSOZAI.113.735
G. Wild, D. Prlce
{"title":"Some Aspects of Relationship between Output of Shearer Main Motor and Production Volume of Shearer Drum.","authors":"G. Wild, D. Prlce","doi":"10.2473/SHIGENTOSOZAI.113.735","DOIUrl":"https://doi.org/10.2473/SHIGENTOSOZAI.113.735","url":null,"abstract":"","PeriodicalId":22754,"journal":{"name":"The Mining and Materials Processing Institute of Japan","volume":"21 1","pages":"735-737"},"PeriodicalIF":0.0,"publicationDate":"1997-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75080144","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 : 1997-01-01DOI: 10.2473/SHIGENTOSOZAI.113.565
F. Kiyono, T. Saito
In the field of water jet technology the improvement of cutting efficiency has been recognized as one of the most important research targets. To solve this problem an oscillating jet nozzle was developed. In this nozzle several piezo-electric transducers are attached to a vibration plate, and through this plate oscillation of piezoelectric transducers is propagated to inner high pressure water, then oscillating jets emanate from a nozzle outlet.To optimize the efficiency of the oscillating jet nozzle an appropriate frequency must be selected undergiven water jet velocity and jet diameter.In this paper the authors examine this problem from the point of hydrodynamic stability of oscillating jets. Firstly the diagram for selecting the optimum oscillation frequency is presented. Then experimental results are compared with theoretical results which were predicted by the hydrodynamic stability theory. Both results show qualitative agreement.
{"title":"Axial Propagation Property of Oscillation in Water Jets.","authors":"F. Kiyono, T. Saito","doi":"10.2473/SHIGENTOSOZAI.113.565","DOIUrl":"https://doi.org/10.2473/SHIGENTOSOZAI.113.565","url":null,"abstract":"In the field of water jet technology the improvement of cutting efficiency has been recognized as one of the most important research targets. To solve this problem an oscillating jet nozzle was developed. In this nozzle several piezo-electric transducers are attached to a vibration plate, and through this plate oscillation of piezoelectric transducers is propagated to inner high pressure water, then oscillating jets emanate from a nozzle outlet.To optimize the efficiency of the oscillating jet nozzle an appropriate frequency must be selected undergiven water jet velocity and jet diameter.In this paper the authors examine this problem from the point of hydrodynamic stability of oscillating jets. Firstly the diagram for selecting the optimum oscillation frequency is presented. Then experimental results are compared with theoretical results which were predicted by the hydrodynamic stability theory. Both results show qualitative agreement.","PeriodicalId":22754,"journal":{"name":"The Mining and Materials Processing Institute of Japan","volume":"59 1","pages":"565-570"},"PeriodicalIF":0.0,"publicationDate":"1997-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83991536","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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