Pub Date : 2023-11-29DOI: 10.1186/s43065-023-00092-7
Kazi Naimul Hoque, Francisco Presuel-Moreno, Manzurul Nazim
Samples with two different binary blended concrete mixes were prepared, one containing cement replacement of 50% slag (referred here as SL mix) and the other containing cement replacement of 20% fly ash (termed here as FA mix). The water to cementitious ratio used to produce concrete specimens was 0.41. On the top surface of each specimen, various reservoir lengths that ranged from 2.5 cm to 17.5 cm were fitted, and these reservoirs were filled with a 10% NaCl solution. Electromigration was used to accelerate the transport of chlorides, with an applied potential of 9 V at first, and subsequently reduced to 3 V after about a week. The electromigration was applied for a short period (few weeks to a couple of months). For a period of about 1100 days, the corrosion related parameters such as concrete solution resistance, rebar potential, and corrosion current were monitored via the rebar potential measurements, linear polarization resistance (LPR) and electrochemical impedance spectroscopy (EIS) measurements, the latter used only to obtain the solution resistance. The corrosion current values determined through experimental observations were then converted to mass loss using Faraday’s law. The readings of corrosion current values (last 7 sets of readings) as well as the calculated mass loss values were found to be larger for the rebars embedded in specimens prepared with SL mix, followed by rebars embedded in specimens prepared with FA mix. Corrosion current and calculated mass loss values in general tended to increase with increasing solution reservoir lengths. No cracks or corrosion products that reached the surface of the concrete were observed on the specimens for the duration of the reported monitored propagation period. This study offers a framework for future studies on accelerated steel corrosion in concrete.
{"title":"Corrosion of carbon steel rebar in binary blended concrete with accelerated chloride transport","authors":"Kazi Naimul Hoque, Francisco Presuel-Moreno, Manzurul Nazim","doi":"10.1186/s43065-023-00092-7","DOIUrl":"https://doi.org/10.1186/s43065-023-00092-7","url":null,"abstract":"Samples with two different binary blended concrete mixes were prepared, one containing cement replacement of 50% slag (referred here as SL mix) and the other containing cement replacement of 20% fly ash (termed here as FA mix). The water to cementitious ratio used to produce concrete specimens was 0.41. On the top surface of each specimen, various reservoir lengths that ranged from 2.5 cm to 17.5 cm were fitted, and these reservoirs were filled with a 10% NaCl solution. Electromigration was used to accelerate the transport of chlorides, with an applied potential of 9 V at first, and subsequently reduced to 3 V after about a week. The electromigration was applied for a short period (few weeks to a couple of months). For a period of about 1100 days, the corrosion related parameters such as concrete solution resistance, rebar potential, and corrosion current were monitored via the rebar potential measurements, linear polarization resistance (LPR) and electrochemical impedance spectroscopy (EIS) measurements, the latter used only to obtain the solution resistance. The corrosion current values determined through experimental observations were then converted to mass loss using Faraday’s law. The readings of corrosion current values (last 7 sets of readings) as well as the calculated mass loss values were found to be larger for the rebars embedded in specimens prepared with SL mix, followed by rebars embedded in specimens prepared with FA mix. Corrosion current and calculated mass loss values in general tended to increase with increasing solution reservoir lengths. No cracks or corrosion products that reached the surface of the concrete were observed on the specimens for the duration of the reported monitored propagation period. This study offers a framework for future studies on accelerated steel corrosion in concrete.","PeriodicalId":73793,"journal":{"name":"Journal of infrastructure preservation and resilience","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138523940","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 : 2023-11-20DOI: 10.1186/s43065-023-00087-4
Idorenyin Ndarake Usanga, Fidelis Onyebuchi Okafor, Chijioke Christopher Ikeagwuani
Recently, there has been a trend among pavement engineers and scientists to utilize natural mineral resources found in different parts of the world to develop and enhance sustainable infrastructure. One of such materials is calcined clay. However, the fatigue performance of asphalt mixtures made with these alternative materials needs to be properly studied. Due to its complex composition, asphalt concrete exhibits diverse non-linear characteristics when subjected to different conditions. As such, the impact of rest time, considering the effect of hardening relaxation and healing on the creep recovery of asphalt mixtures modified with calcined marl filler (CMF), has been evaluated in this present study. Thus, the locally sourced marl was pulverized and calcined to produce CMF. Different amounts of CMF were added to asphalt mixtures as a mineral filler, ranging from 0% to 100% by weight. Afterwards, the rheological properties of CMF mastic using a dynamic shear rheometer (DSR) were investigated. Notably, the outcomes of the experiments revealed compelling insights. Specifically, under the influence of 50% CMF modification, the asphalt mixtures exhibited a remarkable rutting resistance, with values reaching 12.7 kPa for unaged conditions and 16.1 kPa for aged conditions. Additionally, the results underscored an enhancement in the low-temperature characteristics of the bitumen mastic, which consequently contributed to heightened resistance against fatigue-induced damage. Furthermore, the statistical analysis, such as the student t-test, deployed to compare the creep recovery with and without rest time indicated that the creep recovery changes with the application of rest time. Hence, at long rest times, the hardening relaxation behavior reduces and the chances of healing increase, leading to a decrease in the amount of deformation in the samples.
{"title":"Impact of rest time on creep recovery of asphalt mixtures modified with calcined marl filler","authors":"Idorenyin Ndarake Usanga, Fidelis Onyebuchi Okafor, Chijioke Christopher Ikeagwuani","doi":"10.1186/s43065-023-00087-4","DOIUrl":"https://doi.org/10.1186/s43065-023-00087-4","url":null,"abstract":"Recently, there has been a trend among pavement engineers and scientists to utilize natural mineral resources found in different parts of the world to develop and enhance sustainable infrastructure. One of such materials is calcined clay. However, the fatigue performance of asphalt mixtures made with these alternative materials needs to be properly studied. Due to its complex composition, asphalt concrete exhibits diverse non-linear characteristics when subjected to different conditions. As such, the impact of rest time, considering the effect of hardening relaxation and healing on the creep recovery of asphalt mixtures modified with calcined marl filler (CMF), has been evaluated in this present study. Thus, the locally sourced marl was pulverized and calcined to produce CMF. Different amounts of CMF were added to asphalt mixtures as a mineral filler, ranging from 0% to 100% by weight. Afterwards, the rheological properties of CMF mastic using a dynamic shear rheometer (DSR) were investigated. Notably, the outcomes of the experiments revealed compelling insights. Specifically, under the influence of 50% CMF modification, the asphalt mixtures exhibited a remarkable rutting resistance, with values reaching 12.7 kPa for unaged conditions and 16.1 kPa for aged conditions. Additionally, the results underscored an enhancement in the low-temperature characteristics of the bitumen mastic, which consequently contributed to heightened resistance against fatigue-induced damage. Furthermore, the statistical analysis, such as the student t-test, deployed to compare the creep recovery with and without rest time indicated that the creep recovery changes with the application of rest time. Hence, at long rest times, the hardening relaxation behavior reduces and the chances of healing increase, leading to a decrease in the amount of deformation in the samples.","PeriodicalId":73793,"journal":{"name":"Journal of infrastructure preservation and resilience","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138523933","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 : 2023-11-10DOI: 10.1186/s43065-023-00090-9
Yusheng Jiang, Xiong Yu
Abstract In cold regions, the environment dynamics lead to variations of soil temperature, water content, and deformation, which are characterized by highly coupled physical interplay. The hydraulic and thermal properties of unsaturated soils are highly nonlinear, which is further complicated when subjected to freezing. This paper presents a comprehensive multiphysics coupling model to evaluate these complex processes. The model considers the behaviors of unsaturated frozen soils. It accounts for the influences of meteorological, geothermal, and hydrological factors. The model is validated through two pavement case studies using Long-Term Pavement Performance (LTPP) road section data. The first case analysis is performed for a pavement section in Vermont, and the simulation lasted for 30 days during a non-freezing season on an hourly basis. The results validated the performance of the model considering unsaturated soil behaviors. The second case study is based on a daily analysis of a pavement section in South Dakota over a freezing–thawing cycle over 194 days. The results validated the model in considering the frozen unsaturated soil behaviors. Both case studies demonstrate the performance of this comprehensive model in quantifying the spatial and temporal variations of soil temperature and water content in response to environmental stressors. The capability of the model in accurately predicting the responses of pavement to the meteorological factors unleashes the potential of this model to assess the effects of climate and climate change on cold region pavement, as well as other types of geo-structures.
{"title":"Holistic multiphysics simulation of climatic responses of cold region pavements","authors":"Yusheng Jiang, Xiong Yu","doi":"10.1186/s43065-023-00090-9","DOIUrl":"https://doi.org/10.1186/s43065-023-00090-9","url":null,"abstract":"Abstract In cold regions, the environment dynamics lead to variations of soil temperature, water content, and deformation, which are characterized by highly coupled physical interplay. The hydraulic and thermal properties of unsaturated soils are highly nonlinear, which is further complicated when subjected to freezing. This paper presents a comprehensive multiphysics coupling model to evaluate these complex processes. The model considers the behaviors of unsaturated frozen soils. It accounts for the influences of meteorological, geothermal, and hydrological factors. The model is validated through two pavement case studies using Long-Term Pavement Performance (LTPP) road section data. The first case analysis is performed for a pavement section in Vermont, and the simulation lasted for 30 days during a non-freezing season on an hourly basis. The results validated the performance of the model considering unsaturated soil behaviors. The second case study is based on a daily analysis of a pavement section in South Dakota over a freezing–thawing cycle over 194 days. The results validated the model in considering the frozen unsaturated soil behaviors. Both case studies demonstrate the performance of this comprehensive model in quantifying the spatial and temporal variations of soil temperature and water content in response to environmental stressors. The capability of the model in accurately predicting the responses of pavement to the meteorological factors unleashes the potential of this model to assess the effects of climate and climate change on cold region pavement, as well as other types of geo-structures.","PeriodicalId":73793,"journal":{"name":"Journal of infrastructure preservation and resilience","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135137678","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 : 2023-11-07DOI: 10.1186/s43065-023-00091-8
Xiaoqiang Ni, Matias Leon-Miquel, Quentin R. Greiner, Alvaro Paul, Qingxu Jin
Abstract Crack sealers are crucial for preserving concrete bridge decks and extending their service life. This paper presents a comprehensive national survey in the U.S., gathering responses from a total of 37 different agencies, along with literature studies on crack sealer practices in concrete bridge decks. The study covers various aspects, including available crack sealers, sealing triggers, approved product list and performance, resealing intervals, method selection, and surface preparation. Based on the study findings, epoxy, methyl methacrylate (MMA), and high-molecular-weight methacrylate (HMWM) are the most commonly used crack sealers, each offering distinct advantages. Sealing criteria are based on crack dimensions and deicing exposure. Resealing intervals vary due to sealant composition, deck age, and climate. Method selection considers deck attributes, temperature, and moisture. The study identifies gaps in consistently approved product lists and suggests future research areas, such as investigating the effects of entrapped chloride, conducting long-term performance testing, and correlating laboratory and field data. The study’s findings contribute to current practices, facilitating decision-making and providing guidance for targeted future research.
{"title":"Crack sealers for the preservation of concrete bridge decks: a synthesis of a national survey and literature review","authors":"Xiaoqiang Ni, Matias Leon-Miquel, Quentin R. Greiner, Alvaro Paul, Qingxu Jin","doi":"10.1186/s43065-023-00091-8","DOIUrl":"https://doi.org/10.1186/s43065-023-00091-8","url":null,"abstract":"Abstract Crack sealers are crucial for preserving concrete bridge decks and extending their service life. This paper presents a comprehensive national survey in the U.S., gathering responses from a total of 37 different agencies, along with literature studies on crack sealer practices in concrete bridge decks. The study covers various aspects, including available crack sealers, sealing triggers, approved product list and performance, resealing intervals, method selection, and surface preparation. Based on the study findings, epoxy, methyl methacrylate (MMA), and high-molecular-weight methacrylate (HMWM) are the most commonly used crack sealers, each offering distinct advantages. Sealing criteria are based on crack dimensions and deicing exposure. Resealing intervals vary due to sealant composition, deck age, and climate. Method selection considers deck attributes, temperature, and moisture. The study identifies gaps in consistently approved product lists and suggests future research areas, such as investigating the effects of entrapped chloride, conducting long-term performance testing, and correlating laboratory and field data. The study’s findings contribute to current practices, facilitating decision-making and providing guidance for targeted future research.","PeriodicalId":73793,"journal":{"name":"Journal of infrastructure preservation and resilience","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135476616","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 : 2023-10-24DOI: 10.1186/s43065-023-00089-2
Idorenyin Ndarake Usanga, Fidelis Onyebuchi Okafor, Chijioke Christopher Ikeagwuani
Abstract In response to the demand for a greener approach to pavement infrastructure and the economic benefits associated with alternative materials, the modification of neat binders has been a consistent focus. This research aimed to enhance the characteristics of asphalt binders and mixtures by incorporating recycled vegetable oil (RVO) and nanomarl. RVO was added to 60/70 penetration bitumen at concentrations of 1%, 3%, and 5% by weight, while nanomarl was kept constant at 5% by weight of the bitumen. Various physical, rheological, and microstructural properties of the modified binders were evaluated, including penetration, softening point, viscosity, rutting resistance, fatigue resistance, creep, stiffness, scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). Furthermore, the moisture susceptibility and rutting resistance performance of asphalt mixtures incorporating these modified binders were investigated through analyses of tensile strength ratio and Hamburg wheel tracking. The test results revealed that the incorporation of RVO in bitumen led to a gradual increase in the penetration value of the modified bitumen. Simultaneously, the softening point and viscosity of the modified bitumen decreased, indicating that the addition of oil rendered the modified bitumen softer. However, the inclusion of nanomarl in RVO-modified bitumen improved its viscoelastic behavior and positively influenced its rheological properties under both unaged and aged conditions. Specifically, the addition of 5% nanomarl resulted in reduced penetration value, increased softening point, viscosity, rutting resistance, fatigue resistance, creep stiffness, and improved relaxation behavior at low temperatures. The most favorable outcomes were observed when incorporating 1% RVO with 5% nanomarl. Moreover, SEM and FTIR analysis demonstrated successful blending of the additives into the bitumen, without any evidence of phase separation. This indicates a homogeneous distribution of the additives within the bitumen matrix. Practical application: The modification of bitumen with waste or recycled oils for the production of asphalt mixture has been successfully studied in numerous researches. However, this study introduces a novel approach by synergistically combining recycled vegetable oil (RVO) modification with the incorporation of nanomarl particles into asphalt mixture. The innovation aspect lies in the integration of two sustainable and environmentally friendly components, RVO and nanomral, to enhance asphalt performance. The findings offer a blueprint for incorporating sustainable materials and approaches in road construction projects. Pavement engineers can adopt the use of RVO modification and nanomarl particles to create longer-lasting and environmentally friendly asphalt pavements. In regions with challenging climatic conditions, the use of this modified asphalt can lead to improved infrastructure resilience. Roads built with these m
{"title":"Effect of recycled vegetable oil on the performance of nanomarl-modified asphalt mixtures","authors":"Idorenyin Ndarake Usanga, Fidelis Onyebuchi Okafor, Chijioke Christopher Ikeagwuani","doi":"10.1186/s43065-023-00089-2","DOIUrl":"https://doi.org/10.1186/s43065-023-00089-2","url":null,"abstract":"Abstract In response to the demand for a greener approach to pavement infrastructure and the economic benefits associated with alternative materials, the modification of neat binders has been a consistent focus. This research aimed to enhance the characteristics of asphalt binders and mixtures by incorporating recycled vegetable oil (RVO) and nanomarl. RVO was added to 60/70 penetration bitumen at concentrations of 1%, 3%, and 5% by weight, while nanomarl was kept constant at 5% by weight of the bitumen. Various physical, rheological, and microstructural properties of the modified binders were evaluated, including penetration, softening point, viscosity, rutting resistance, fatigue resistance, creep, stiffness, scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). Furthermore, the moisture susceptibility and rutting resistance performance of asphalt mixtures incorporating these modified binders were investigated through analyses of tensile strength ratio and Hamburg wheel tracking. The test results revealed that the incorporation of RVO in bitumen led to a gradual increase in the penetration value of the modified bitumen. Simultaneously, the softening point and viscosity of the modified bitumen decreased, indicating that the addition of oil rendered the modified bitumen softer. However, the inclusion of nanomarl in RVO-modified bitumen improved its viscoelastic behavior and positively influenced its rheological properties under both unaged and aged conditions. Specifically, the addition of 5% nanomarl resulted in reduced penetration value, increased softening point, viscosity, rutting resistance, fatigue resistance, creep stiffness, and improved relaxation behavior at low temperatures. The most favorable outcomes were observed when incorporating 1% RVO with 5% nanomarl. Moreover, SEM and FTIR analysis demonstrated successful blending of the additives into the bitumen, without any evidence of phase separation. This indicates a homogeneous distribution of the additives within the bitumen matrix. Practical application: The modification of bitumen with waste or recycled oils for the production of asphalt mixture has been successfully studied in numerous researches. However, this study introduces a novel approach by synergistically combining recycled vegetable oil (RVO) modification with the incorporation of nanomarl particles into asphalt mixture. The innovation aspect lies in the integration of two sustainable and environmentally friendly components, RVO and nanomral, to enhance asphalt performance. The findings offer a blueprint for incorporating sustainable materials and approaches in road construction projects. Pavement engineers can adopt the use of RVO modification and nanomarl particles to create longer-lasting and environmentally friendly asphalt pavements. In regions with challenging climatic conditions, the use of this modified asphalt can lead to improved infrastructure resilience. Roads built with these m","PeriodicalId":73793,"journal":{"name":"Journal of infrastructure preservation and resilience","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135266488","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 : 2023-08-21DOI: 10.1186/s43065-023-00086-5
Xudong Fan, X. Yu
{"title":"Machine learning-assisted optimal schedule of underground water pipe inspection","authors":"Xudong Fan, X. Yu","doi":"10.1186/s43065-023-00086-5","DOIUrl":"https://doi.org/10.1186/s43065-023-00086-5","url":null,"abstract":"","PeriodicalId":73793,"journal":{"name":"Journal of infrastructure preservation and resilience","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45822085","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 : 2023-07-31DOI: 10.1186/s43065-023-00083-8
M. Barzegar, Haifang Wen
{"title":"Modeling roadway temperatures for wildfire evacuation and assessment of pavement damage","authors":"M. Barzegar, Haifang Wen","doi":"10.1186/s43065-023-00083-8","DOIUrl":"https://doi.org/10.1186/s43065-023-00083-8","url":null,"abstract":"","PeriodicalId":73793,"journal":{"name":"Journal of infrastructure preservation and resilience","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41644758","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 : 2023-07-28DOI: 10.1186/s43065-023-00082-9
Yong Deng, Xianming Shi
{"title":"Modeling the rutting performance of asphalt pavements: a review","authors":"Yong Deng, Xianming Shi","doi":"10.1186/s43065-023-00082-9","DOIUrl":"https://doi.org/10.1186/s43065-023-00082-9","url":null,"abstract":"","PeriodicalId":73793,"journal":{"name":"Journal of infrastructure preservation and resilience","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44591420","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":"Development of decision-making system measuring the resilience level of highway projects","authors":"Thahomina Jahan Nipa, Sharareh Kermanshachi, Apurva Pamidimukkala","doi":"10.1186/s43065-023-00084-7","DOIUrl":"https://doi.org/10.1186/s43065-023-00084-7","url":null,"abstract":"","PeriodicalId":73793,"journal":{"name":"Journal of infrastructure preservation and resilience","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42927321","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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