{"title":"Asphalt Fume Generation-Enrichment Device Development and Fume Production Estimation Model","authors":"Ping Li, Meng Wang, Tengfei Nian, Yu Mao, Mei Lin","doi":"10.1520/acem20210056","DOIUrl":"https://doi.org/10.1520/acem20210056","url":null,"abstract":"","PeriodicalId":51766,"journal":{"name":"Advances in Civil Engineering Materials","volume":"20 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83359614","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}
Francisco W. Jativa, P. Hosseini, M. Gabr, M. Pour-Ghaz
{"title":"Effects of MgSO4 on Calcium-Silicate-Hydrate","authors":"Francisco W. Jativa, P. Hosseini, M. Gabr, M. Pour-Ghaz","doi":"10.1520/acem20210013","DOIUrl":"https://doi.org/10.1520/acem20210013","url":null,"abstract":"","PeriodicalId":51766,"journal":{"name":"Advances in Civil Engineering Materials","volume":"7 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75240090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Preparation and Experimental Investigation on Mechanical and Tribological Performance of Hemp-Glass Fiber Reinforced Laminated Composites for Lightweight Applications","authors":"G. Arpitha, Akarsh Verma, M. Sanjay, S. Siengchin","doi":"10.1520/acem20200187","DOIUrl":"https://doi.org/10.1520/acem20200187","url":null,"abstract":"","PeriodicalId":51766,"journal":{"name":"Advances in Civil Engineering Materials","volume":"24 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74512207","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}
Previous research has shown that using fine lightweight aggregate (FLWA) can be a promising strategy to mitigate alkali-silica reaction (ASR) in mortar and concrete. However, limited studies focused on assessing current ASTM standards for their applicability in evaluating the efficacy of ASR mitigation using FLWAs. In this study, three commercially used FLWAs (expanded shale, clay, and slate) were investigated in mortar and concrete mixtures with reactive aggregates of different levels of reactivity. ASTM test methods, including ASTM C289-07, Standard Test Method for Potential Alkali-Silica Reactivity of Aggregates (Chemical Method) (Withdrawn 2016); ASTM C1260-14, Standard Test Method for Potential Alkali Reactivity of Aggregates (Mortar-Bar Method) (Superseded); and ASTM C1293-18, Standard Test Method for Determination of Length Change of Concrete due to Alkali-Silica Reaction (Superseded), were completed. Fine normal-weight aggregates were replaced by the FLWA at 25 % and 50 % by volume in the concrete mixtures, and 25 %, 50 %, and 100 % in mortar mixtures. Results showed that ASTM C1260-14 and ASTM C1293-18 can be used to evaluate the mitigation efficacy when pre-wetted FLWAs were used. The ASTM C289-07 test is not a reliable test method to study the reactivity of the FLWAs, but the results can be used to indicate the alkali-consuming ability of the FLWAs. All three FLWAs were effective in reducing ASR-induced expansion in both ASTM C1260-14 and ASTM C1293-18. The investigated FLWAs were especially effective in the concrete when moderately reactive aggregates, as classified by ASTM C1778-14, Standard Guide for Reducing the Risk of Deleterious Alkali-Aggregate Reaction in Concrete (Superseded), were used. For concrete with a highly reactive aggregate or very highly reactive aggregate, other mitigation strategies may need to be combined with FLWAs to effectively mitigate ASR.
{"title":"Evaluation of Current ASTM Standards for ASR Prevention When Fine Lightweight Aggregates Are Used","authors":"Chang Li, J. Ideker, M. Thomas","doi":"10.1520/acem20200076","DOIUrl":"https://doi.org/10.1520/acem20200076","url":null,"abstract":"Previous research has shown that using fine lightweight aggregate (FLWA) can be a promising strategy to mitigate alkali-silica reaction (ASR) in mortar and concrete. However, limited studies focused on assessing current ASTM standards for their applicability in evaluating the efficacy of ASR mitigation using FLWAs. In this study, three commercially used FLWAs (expanded shale, clay, and slate) were investigated in mortar and concrete mixtures with reactive aggregates of different levels of reactivity. ASTM test methods, including ASTM C289-07, Standard Test Method for Potential Alkali-Silica Reactivity of Aggregates (Chemical Method) (Withdrawn 2016); ASTM C1260-14, Standard Test Method for Potential Alkali Reactivity of Aggregates (Mortar-Bar Method) (Superseded); and ASTM C1293-18, Standard Test Method for Determination of Length Change of Concrete due to Alkali-Silica Reaction (Superseded), were completed. Fine normal-weight aggregates were replaced by the FLWA at 25 % and 50 % by volume in the concrete mixtures, and 25 %, 50 %, and 100 % in mortar mixtures. Results showed that ASTM C1260-14 and ASTM C1293-18 can be used to evaluate the mitigation efficacy when pre-wetted FLWAs were used. The ASTM C289-07 test is not a reliable test method to study the reactivity of the FLWAs, but the results can be used to indicate the alkali-consuming ability of the FLWAs. All three FLWAs were effective in reducing ASR-induced expansion in both ASTM C1260-14 and ASTM C1293-18. The investigated FLWAs were especially effective in the concrete when moderately reactive aggregates, as classified by ASTM C1778-14, Standard Guide for Reducing the Risk of Deleterious Alkali-Aggregate Reaction in Concrete (Superseded), were used. For concrete with a highly reactive aggregate or very highly reactive aggregate, other mitigation strategies may need to be combined with FLWAs to effectively mitigate ASR.","PeriodicalId":51766,"journal":{"name":"Advances in Civil Engineering Materials","volume":"705 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77466855","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}
Several countries have started using recycled aggregate as a partial replacement to natural aggregate in concrete. Recycled aggregate contains adhered mortar, which distinguishes it from the natural aggregate. In the present study, natural coarse aggregates were entirely replaced by two kinds of recycled coarse aggregates. The recycled aggregates obtained from the jaw crushing method were named recycled coarse aggregate-1 and the aggregates that were further processed by the ball milling method were named recycled coarse aggregate-2. The performance of control concrete and two kinds of recycled coarse aggregate concretes were studied experimentally with respect to mechanical properties. Results indicate that the processing method to obtain recycled coarse aggregates plays an important role in developing the required mechanical properties. The ball mill processed aggregates performed better than the jaw crushed aggregates in concrete. The performance was also assessed with respect to the microhardness of the interfacial transition zone around the surface of the aggregates. The presence of adhered mortar in recycled aggregate weakens it because of the presence of an old interfacial transition zone that affects the strength of concrete. The interfacial transition zone hardness at the aggregate-mortar interface is 53.94, 34.21, and 44.08 % of bulk concrete for control concrete, recycled coarse aggregate-1 concrete, and recycled coarse aggregate-2 concrete, respectively. The addition of silica fume improved the average microhardness, and the same was reflected in the mechanical properties of both the recycled coarse aggregate concretes. It is recommended to use ball mill processed recycled coarse aggregates as a complete replacement to natural coarse aggregates along with a 5 % addition of silica fume for better performance.
{"title":"Influence of Silica Fume on Mechanical Properties and Microhardness of Interfacial Transition Zone of Different Recycled Aggregate Concretes","authors":"S. V. Patil, K. B. Rao, G. Nayak","doi":"10.1520/acem20210011","DOIUrl":"https://doi.org/10.1520/acem20210011","url":null,"abstract":"Several countries have started using recycled aggregate as a partial replacement to natural aggregate in concrete. Recycled aggregate contains adhered mortar, which distinguishes it from the natural aggregate. In the present study, natural coarse aggregates were entirely replaced by two kinds of recycled coarse aggregates. The recycled aggregates obtained from the jaw crushing method were named recycled coarse aggregate-1 and the aggregates that were further processed by the ball milling method were named recycled coarse aggregate-2. The performance of control concrete and two kinds of recycled coarse aggregate concretes were studied experimentally with respect to mechanical properties. Results indicate that the processing method to obtain recycled coarse aggregates plays an important role in developing the required mechanical properties. The ball mill processed aggregates performed better than the jaw crushed aggregates in concrete. The performance was also assessed with respect to the microhardness of the interfacial transition zone around the surface of the aggregates. The presence of adhered mortar in recycled aggregate weakens it because of the presence of an old interfacial transition zone that affects the strength of concrete. The interfacial transition zone hardness at the aggregate-mortar interface is 53.94, 34.21, and 44.08 % of bulk concrete for control concrete, recycled coarse aggregate-1 concrete, and recycled coarse aggregate-2 concrete, respectively. The addition of silica fume improved the average microhardness, and the same was reflected in the mechanical properties of both the recycled coarse aggregate concretes. It is recommended to use ball mill processed recycled coarse aggregates as a complete replacement to natural coarse aggregates along with a 5 % addition of silica fume for better performance.","PeriodicalId":51766,"journal":{"name":"Advances in Civil Engineering Materials","volume":"50 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86260027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Evaluation of Strength and Water Susceptibility Performance of Polypropylene Fiber–Reinforced and Silica Fume–Modified Hot Mix Asphalt","authors":"Nitin Tiwari, N. Satyam","doi":"10.1520/acem20210029","DOIUrl":"https://doi.org/10.1520/acem20210029","url":null,"abstract":"","PeriodicalId":51766,"journal":{"name":"Advances in Civil Engineering Materials","volume":"20 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78964147","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}
Cellular concrete, also known as foamed concrete, has been widely used in different geotechnical and nonstructural applications owing to a unique geometric nature that results in low density and high flowability and its low construction cost. The behavior of cellular concrete under impact or penetration has also drawn attention in applications such as engineered material arrestor systems, emergency escape ramps, and crash barriers. The high void content inside cellular concrete allows it to undertake large deformation, which could lead to high energy absorption. However, there is still a lack of fundamental understanding of the energy absorption of the material and response of the material under impact or penetration. This paper carries out an investigation of the response of cellular concrete subjected to low-velocity impact and penetration. Cellular concretes with different foaming agents and with fibers were prepared and evaluated. Experimental results demonstrated the superior ability of cellular concrete in absorbing and dissipating impact and penetration energies compared with conventional concrete. The paper shows that through steadily deforming the internal void structure, cellular concrete can diminish the reaction force caused by a collision and dissipate penetration energy. Results of the study can help to better understand the mechanism of energy absorption of cellular concrete so as to better tailor it for different applications.
{"title":"Performance of Cellular Concrete under Low-Velocity Impact and Penetration","authors":"F. Mendonça, Jiong Hu","doi":"10.1520/acem20210063","DOIUrl":"https://doi.org/10.1520/acem20210063","url":null,"abstract":"Cellular concrete, also known as foamed concrete, has been widely used in different geotechnical and nonstructural applications owing to a unique geometric nature that results in low density and high flowability and its low construction cost. The behavior of cellular concrete under impact or penetration has also drawn attention in applications such as engineered material arrestor systems, emergency escape ramps, and crash barriers. The high void content inside cellular concrete allows it to undertake large deformation, which could lead to high energy absorption. However, there is still a lack of fundamental understanding of the energy absorption of the material and response of the material under impact or penetration. This paper carries out an investigation of the response of cellular concrete subjected to low-velocity impact and penetration. Cellular concretes with different foaming agents and with fibers were prepared and evaluated. Experimental results demonstrated the superior ability of cellular concrete in absorbing and dissipating impact and penetration energies compared with conventional concrete. The paper shows that through steadily deforming the internal void structure, cellular concrete can diminish the reaction force caused by a collision and dissipate penetration energy. Results of the study can help to better understand the mechanism of energy absorption of cellular concrete so as to better tailor it for different applications.","PeriodicalId":51766,"journal":{"name":"Advances in Civil Engineering Materials","volume":"8 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81980120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effectiveness of Microbially Induced Calcite Precipitation for Treating Expansive Soils","authors":"R. Wei, J. Z. Xiao, S. F. Wu, H. Cai, Z. W. Wang","doi":"10.1520/acem20200182","DOIUrl":"https://doi.org/10.1520/acem20200182","url":null,"abstract":"","PeriodicalId":51766,"journal":{"name":"Advances in Civil Engineering Materials","volume":"39 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80600985","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}
The X-ray diffraction (XRD) signature of the glassy phase in blast furnace slag undergoing alkaline dissolution is evaluated. The intensity signature of the glassy phase present in slag can consistently be decomposed into three underlying pseudo-Voigt (PV) peaks. It is shown that the fundamental underlying characteristics of the XRD signature of the undissolved glassy phase of slag in terms of the underlying PV peaks do not change after dissolution in an alkaline solution. The stability of the calcium ions depends on the [OH−] concentration in the solution. An intensity-based procedure is developed for quantifying the unreacted glassy phase content in alkali-activated slag. The XRD profile information of the glassy phase in raw slag is suitable for fitting the intensity profile of the dissolved glassy phase. The mass percentage of the unreacted glassy phase of slag within alkali-activated slag is validated with selective acid dissolution. A procedure for determining the degree of reaction in alkali-activated slag is established. The procedure developed here could be used to determine the activity of slag in an alkaline environment.
{"title":"X-ray Diffraction-Based Quantification of Amorphous Phase in Alkali-Activated Blast Furnace Slag","authors":"K. C. Reddy, K. Subramaniam","doi":"10.1520/ACEM20200167","DOIUrl":"https://doi.org/10.1520/ACEM20200167","url":null,"abstract":"The X-ray diffraction (XRD) signature of the glassy phase in blast furnace slag undergoing alkaline dissolution is evaluated. The intensity signature of the glassy phase present in slag can consistently be decomposed into three underlying pseudo-Voigt (PV) peaks. It is shown that the fundamental underlying characteristics of the XRD signature of the undissolved glassy phase of slag in terms of the underlying PV peaks do not change after dissolution in an alkaline solution. The stability of the calcium ions depends on the [OH−] concentration in the solution. An intensity-based procedure is developed for quantifying the unreacted glassy phase content in alkali-activated slag. The XRD profile information of the glassy phase in raw slag is suitable for fitting the intensity profile of the dissolved glassy phase. The mass percentage of the unreacted glassy phase of slag within alkali-activated slag is validated with selective acid dissolution. A procedure for determining the degree of reaction in alkali-activated slag is established. The procedure developed here could be used to determine the activity of slag in an alkaline environment.","PeriodicalId":51766,"journal":{"name":"Advances in Civil Engineering Materials","volume":"8 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89138787","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. Montanari, Jussara Tanesi, Haejin Kim, A. Ardani
The American Association of State Highway and Transportation Officials (AASHTO) T 365 standard, Standard Method of Test for Quantifying Calcium Oxychloride Formation Potential of Cementitious Pastes Exposed to Deicing Salts, describes a test methodology that uses low-temperature differential scanning calorimetry (LTDSC) to quantify the formation of calcium oxychloride in cementitious systems exposed to concentrated calcium chloride solutions. AASHTO T 365 is included in AASHTO PP 84, Standard Practice for Developing Performance Engineered Concrete Pavement Mixtures, as a performance indicator for mixtures at risk of calcium oxychloride formation. During the test, the sample temperature is first dropped to −90°C, looped through a brief thermal cycle, then slowly increased to a maximum of 50°C, at a constant heating rate of 0.25°C/minute (min), for a total testing time of approximately 11 hours. The objective of this work is to modify the test to reduce its duration to facilitate wide adoption among practitioners. It is found that by increasing the minimum conditioning temperature from −90°C to −5°C, as well as by increasing the heating rate from 0.25°C/min up to 1°C/min, the test duration can be reduced from approximately 10.7 hours to approximately 1.6 hours without any statistically significant difference in the numerical test results, although an offset of the melting peak and a change in its shape were observed. This change can provide valuable savings in terms of time and energy/gas consumption and make AASHTO T 365 more competitive with other available tests for the estimation of calcium oxychloride formation, such as thermogravimetric analysis (TGA). TGA and LTDSC are compared to each other in terms of mixture classification for susceptibility to calcium oxychloride formation. It is shown that the two tests show good agreement, with 85 % of cases (out of 30 tested) receiving the same classification.
美国国家公路和交通官员协会(AASHTO) t365标准，即暴露于除冰盐的胶凝体中氯化钙氧化钙形成电位定量测试的标准方法，描述了一种使用低温差示扫描量热法(LTDSC)定量暴露于浓氯化钙溶液的胶凝体系中氯化钙氧化钙形成的测试方法。AASHTO T 365包含在AASHTO PP 84，开发性能工程混凝土路面混合物的标准实践中，作为有氯化钙形成风险的混合物的性能指标。在测试过程中，首先将样品温度降至- 90°C，循环进行短暂的热循环，然后以0.25°C/分钟(min)的恒定加热速率缓慢升高至最高50°C，总测试时间约为11小时。这项工作的目标是修改测试以减少其持续时间，以促进从业者之间的广泛采用。研究发现，通过将最低调节温度从- 90°C增加到- 5°C，以及将加热速率从0.25°C/min增加到1°C/min，测试持续时间可以从大约10.7小时减少到大约1.6小时，而数值测试结果没有统计学上的显著差异，尽管观察到熔化峰偏移和形状变化。这一变化可以节省宝贵的时间和能源/气体消耗，并使AASHTO T 365与热重分析(TGA)等其他可用的氯化钙形成估计测试相比更具竞争力。TGA和LTDSC在对氯化钙形成敏感性的混合物分类方面进行了比较。结果表明，这两种检测方法具有良好的一致性，85%的病例(在30例检测中)得到相同的分类。
{"title":"Quantification of Calcium Oxychloride by Differential Scanning Calorimetry: Validation and Optimization of the Testing Procedure","authors":"L. Montanari, Jussara Tanesi, Haejin Kim, A. Ardani","doi":"10.1520/ACEM20200122","DOIUrl":"https://doi.org/10.1520/ACEM20200122","url":null,"abstract":"The American Association of State Highway and Transportation Officials (AASHTO) T 365 standard, Standard Method of Test for Quantifying Calcium Oxychloride Formation Potential of Cementitious Pastes Exposed to Deicing Salts, describes a test methodology that uses low-temperature differential scanning calorimetry (LTDSC) to quantify the formation of calcium oxychloride in cementitious systems exposed to concentrated calcium chloride solutions. AASHTO T 365 is included in AASHTO PP 84, Standard Practice for Developing Performance Engineered Concrete Pavement Mixtures, as a performance indicator for mixtures at risk of calcium oxychloride formation. During the test, the sample temperature is first dropped to −90°C, looped through a brief thermal cycle, then slowly increased to a maximum of 50°C, at a constant heating rate of 0.25°C/minute (min), for a total testing time of approximately 11 hours. The objective of this work is to modify the test to reduce its duration to facilitate wide adoption among practitioners. It is found that by increasing the minimum conditioning temperature from −90°C to −5°C, as well as by increasing the heating rate from 0.25°C/min up to 1°C/min, the test duration can be reduced from approximately 10.7 hours to approximately 1.6 hours without any statistically significant difference in the numerical test results, although an offset of the melting peak and a change in its shape were observed. This change can provide valuable savings in terms of time and energy/gas consumption and make AASHTO T 365 more competitive with other available tests for the estimation of calcium oxychloride formation, such as thermogravimetric analysis (TGA). TGA and LTDSC are compared to each other in terms of mixture classification for susceptibility to calcium oxychloride formation. It is shown that the two tests show good agreement, with 85 % of cases (out of 30 tested) receiving the same classification.","PeriodicalId":51766,"journal":{"name":"Advances in Civil Engineering Materials","volume":"17 1","pages":"20200122"},"PeriodicalIF":1.4,"publicationDate":"2021-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74339076","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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