An analytical model was developed in this study for predicting the dynamic temperature profile in natural gas hydrate (NGH) reservoirs that receive heat energy from a geothermal layer for accelerating gas production. The analytical model was validated by a comparison of its result to the result given by a numerical model. The expression of the analytical model shows that, for a given system, the heat transfer is proportional to the mass flow rate and the temperature drop along the heat dissipator wellbore. Applying the analytical model to the NGH reservoir in the Shenhu area, Northern South China Sea, allowed for predicting the dynamic temperature profile in the NGH reservoir. The model result reveals that the NGH reservoir temperature should rise quickly at any heat-affected point, but it should propagate slowly in the radial direction. It should take more than two years to dissociate NGH within 20 m of the heat dissipator wellbore due to only thermal stimulation. Therefore, the geo- thermal stimulation method should be used as a technique for accelerating gas production with depressurization scheme. The formation of gas phase due to the NGH dissociation should reduce the thermal conductivity of the NGH reservoir, while the water phase dropped out from the dissociation should increase the thermal conductivity. The resultant effect should be investigated in the future in laboratories and/or numerical simulation of the dynamic water-gas two-phase flow coupled with heat-transfer mechanism.
{"title":"Mathematical Modeling of Heat Transfer from Geothermal Zones to Natural Gas Hydrate Reservoirs","authors":"G. B.","doi":"10.23880/ppej-16000296","DOIUrl":"https://doi.org/10.23880/ppej-16000296","url":null,"abstract":"An analytical model was developed in this study for predicting the dynamic temperature profile in natural gas hydrate (NGH) reservoirs that receive heat energy from a geothermal layer for accelerating gas production. The analytical model was validated by a comparison of its result to the result given by a numerical model. The expression of the analytical model shows that, for a given system, the heat transfer is proportional to the mass flow rate and the temperature drop along the heat dissipator wellbore. Applying the analytical model to the NGH reservoir in the Shenhu area, Northern South China Sea, allowed for predicting the dynamic temperature profile in the NGH reservoir. The model result reveals that the NGH reservoir temperature should rise quickly at any heat-affected point, but it should propagate slowly in the radial direction. It should take more than two years to dissociate NGH within 20 m of the heat dissipator wellbore due to only thermal stimulation. Therefore, the geo- thermal stimulation method should be used as a technique for accelerating gas production with depressurization scheme. The formation of gas phase due to the NGH dissociation should reduce the thermal conductivity of the NGH reservoir, while the water phase dropped out from the dissociation should increase the thermal conductivity. The resultant effect should be investigated in the future in laboratories and/or numerical simulation of the dynamic water-gas two-phase flow coupled with heat-transfer mechanism.","PeriodicalId":282073,"journal":{"name":"Petroleum & Petrochemical Engineering Journal","volume":"95 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126323566","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}
R & D activity has played an active and rapid role in the prosperity of the developed countries and some developing countries whose economies we have been revitalized to adopt the ideas of knowledge development in their national policy. Scientific research and innovation is a path to economic growth and a driving force in creating competition among the countries’ economies, and in particular in the oil industry.
{"title":"Role of Scientific Research in Improving Operational Performance and Profitability in the Oil Industry","authors":"Mohammed Br","doi":"10.23880/ppej-16000293","DOIUrl":"https://doi.org/10.23880/ppej-16000293","url":null,"abstract":"R & D activity has played an active and rapid role in the prosperity of the developed countries and some developing countries whose economies we have been revitalized to adopt the ideas of knowledge development in their national policy. Scientific research and innovation is a path to economic growth and a driving force in creating competition among the countries’ economies, and in particular in the oil industry.","PeriodicalId":282073,"journal":{"name":"Petroleum & Petrochemical Engineering Journal","volume":"144 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127597510","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}
Current levels of anthropogenic carbon dioxide in the atmosphere are responsible for global warming at scales not seen before. To mitigate this global warming trend, the Intergovernmental Panel on Climate Change (IPCC) has universally adopted the geological carbon storage option. The technical implication of geological carbon storage is that carbon dioxide with a very low dynamic viscosity will be injected to push formation brine with a high viscosity contrast. Consequently, problems of interfacial instability responsible for poor sweep efficiencies encountered in the petroleum industry’s improved oil recovery projects are inevitable. The petroleum industry has used costly mobility control agents in the form of carbon dioxide thickeners to solve problems of poor sweep efficiency in carbon dioxide enhance oil recovery projects. This experience is useful to the geological sequestration community because carbon dioxide geological storage under supercritical conditions is considered an optimized approach. In this paper, We have reviewed literature to show the solubility of waste organics in supercritical carbon dioxide and the possibility to increase its dynamic viscosity to reduce interfacial instability problems. We have, also, reviewed literature to show sources and availability of cheap soluble organics for carbon dioxide thickening. Our review shows promising sources of these soluble organics. Finally, the technical implications of dynamic viscosity increase on a given geological storage project have been discussed in the context of interfacial stability theories.
{"title":"Mobility Control Potential in Geological Sequestration of Anthropogenic Carbon Dioxide using Cheap Soluble Organics as Thickeners and Implications for Interfacial Stability","authors":"Miadonye A","doi":"10.23880/ppej-16000290","DOIUrl":"https://doi.org/10.23880/ppej-16000290","url":null,"abstract":"Current levels of anthropogenic carbon dioxide in the atmosphere are responsible for global warming at scales not seen before. To mitigate this global warming trend, the Intergovernmental Panel on Climate Change (IPCC) has universally adopted the geological carbon storage option. The technical implication of geological carbon storage is that carbon dioxide with a very low dynamic viscosity will be injected to push formation brine with a high viscosity contrast. Consequently, problems of interfacial instability responsible for poor sweep efficiencies encountered in the petroleum industry’s improved oil recovery projects are inevitable. The petroleum industry has used costly mobility control agents in the form of carbon dioxide thickeners to solve problems of poor sweep efficiency in carbon dioxide enhance oil recovery projects. This experience is useful to the geological sequestration community because carbon dioxide geological storage under supercritical conditions is considered an optimized approach. In this paper, We have reviewed literature to show the solubility of waste organics in supercritical carbon dioxide and the possibility to increase its dynamic viscosity to reduce interfacial instability problems. We have, also, reviewed literature to show sources and availability of cheap soluble organics for carbon dioxide thickening. Our review shows promising sources of these soluble organics. Finally, the technical implications of dynamic viscosity increase on a given geological storage project have been discussed in the context of interfacial stability theories.","PeriodicalId":282073,"journal":{"name":"Petroleum & Petrochemical Engineering Journal","volume":"136 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116382007","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}
In this paper, a mono-cationic ionic liquid (MIL) ([BMIM] [NTF 2 ]) and two di-cationic ionic liquids (DILs) ([C 5 (MIM) 2 ][NTF 2 ] 2 and [C 6 (MIM) 2 ][NTF 2 ] 2 ) were synthesized by two-step method, and the conductivity, viscosity and electrochemical stability of the three ionic liquids were systematically studied and analyzed. The results show that the conductivity of MIL is better than that of DILs, while the viscosity and the electrochemical stability of DILs are higher than those of MIL. The viscosity of the DILs decreases with the increasing length of the group within the DILs. Finally, the application of MIL as the electrolyte in the lithium-oxygen battery was studied.
{"title":"Mono-and di-cationic Ionic Liquids: Synthesis, Characterization and Applications in Batteries","authors":"Li-Hua Mao","doi":"10.23880/ppej-16000288","DOIUrl":"https://doi.org/10.23880/ppej-16000288","url":null,"abstract":"In this paper, a mono-cationic ionic liquid (MIL) ([BMIM] [NTF 2 ]) and two di-cationic ionic liquids (DILs) ([C 5 (MIM) 2 ][NTF 2 ] 2 and [C 6 (MIM) 2 ][NTF 2 ] 2 ) were synthesized by two-step method, and the conductivity, viscosity and electrochemical stability of the three ionic liquids were systematically studied and analyzed. The results show that the conductivity of MIL is better than that of DILs, while the viscosity and the electrochemical stability of DILs are higher than those of MIL. The viscosity of the DILs decreases with the increasing length of the group within the DILs. Finally, the application of MIL as the electrolyte in the lithium-oxygen battery was studied.","PeriodicalId":282073,"journal":{"name":"Petroleum & Petrochemical Engineering Journal","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128975157","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 operation risk management and control system is to discuss the daily operation of petrochemical plant by five professionals, including Process Engineer, Safety Engineer, Operator Electrical Instrument Engineer and Equipment maintenance personnel, to arrange weekly plan, identify risks and discuss preventive measures. In this way, the daily total amount of work can be controlled, the risk can be controlled, the efficiency is higher, and the safety in the petrochemical production process can be guaranteed.
{"title":"Five in One Risk Management and Control to Improve Enterprise Safety Management Level","authors":"M. J.","doi":"10.23880/ppej-16000282","DOIUrl":"https://doi.org/10.23880/ppej-16000282","url":null,"abstract":"The operation risk management and control system is to discuss the daily operation of petrochemical plant by five professionals, including Process Engineer, Safety Engineer, Operator Electrical Instrument Engineer and Equipment maintenance personnel, to arrange weekly plan, identify risks and discuss preventive measures. In this way, the daily total amount of work can be controlled, the risk can be controlled, the efficiency is higher, and the safety in the petrochemical production process can be guaranteed.","PeriodicalId":282073,"journal":{"name":"Petroleum & Petrochemical Engineering Journal","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116033372","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 catenary well trajectory is known for its reduced drag and torque during drilling. Modern deflection tools have made it possible to drill catenary well trajectories efficiently, thanks to tool’s capacity of dynamic build rate that creates wellbore profile of varying curvature. However a method to design well trajectory with smooth transition from the kick-out point to the catenary section to reduce “dog-leg” and thus friction is still lacking. This paper presents a 2D mathematical solution to fill the gap. The solution uses equations of closed-form rather than numerical computations. The complete well trajectory profile involves a vertical section, a transitional arc section, a catenary section, and a horizontal/slant section. A case study is presented to compare the friction forces on the drill string in a catenary trajectory profile and a conventional trajectory profile of arc type. The calculation procedure of catenary trajectory design was realized in an MS Excel spreadsheet with direct inputs, which provides an excellent flexibility to meet well trajectory design requirement. The presented mathematical model is an easy-to-use and reliable tool for designing catenary well trajectories in extended-reach wells to minimize wellbore friction and thus increase well depth.
{"title":"An Innovative Method for Designing Smooth Catenary Well Trajectories in Extended-Reach Drilling","authors":"B. Guo","doi":"10.23880/ppej-16000297","DOIUrl":"https://doi.org/10.23880/ppej-16000297","url":null,"abstract":"A catenary well trajectory is known for its reduced drag and torque during drilling. Modern deflection tools have made it possible to drill catenary well trajectories efficiently, thanks to tool’s capacity of dynamic build rate that creates wellbore profile of varying curvature. However a method to design well trajectory with smooth transition from the kick-out point to the catenary section to reduce “dog-leg” and thus friction is still lacking. This paper presents a 2D mathematical solution to fill the gap. The solution uses equations of closed-form rather than numerical computations. The complete well trajectory profile involves a vertical section, a transitional arc section, a catenary section, and a horizontal/slant section. A case study is presented to compare the friction forces on the drill string in a catenary trajectory profile and a conventional trajectory profile of arc type. The calculation procedure of catenary trajectory design was realized in an MS Excel spreadsheet with direct inputs, which provides an excellent flexibility to meet well trajectory design requirement. The presented mathematical model is an easy-to-use and reliable tool for designing catenary well trajectories in extended-reach wells to minimize wellbore friction and thus increase well depth.","PeriodicalId":282073,"journal":{"name":"Petroleum & Petrochemical Engineering Journal","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132064158","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}
Drilling operations in the oil and gas industry takes most of the well cost and how fast the drilling bit penetrate and bore the formation is termed the Rate of penetration (ROP). Since most of the cost incurred during drilling is related to the drilling operations, there is need not only to drill carefully, but also to optimize the drilling process. A lot of parameters are related to the rate of penetration which are actually interdependent on each other. This makes it difficult to predict the influence of every single parameter Drilling optimization techniques have been used recently to reduce drilling operation costs. There are different approaches to optimizing the cost of drilling oil and gas wells, some of which include static and /or real time optimization of drilling parameters. A potential area for optimization of drilling cost is through bit run in the well but this is particularly difficult due to its significance in both drilling time and bit cost. In this sense, as a particular bit gets used, it gets dull as its footage increases, resulting from the reduction in the bit penetration rate. The reduction in penetration rate increases total drill time. In order to optimize bit cost, it is desirable to find a trade-off between the two by a bit change policy This study is aimed at minimizing drilling time by use of artificial intelligent for the bit program. Data obtained from a well in the Niger delta region of Nigeria was used in this study and the cost optimization modelled as a Markov decision process where the intelligent agent was to learn the optimal timings for bit change by reinforcement policy Iteration learning. This study was able to achieve its objectives as the reinforcement learning optimization process performed very well with time as the computer agent was able to figure out how to improve drilling cost over time. Better results could be obtained with a better hardware and increased training time.
{"title":"Optimization of Drilling Cost Using Artificial Intelligence","authors":"Sarah A Akintol","doi":"10.23880/ppej-16000285","DOIUrl":"https://doi.org/10.23880/ppej-16000285","url":null,"abstract":"Drilling operations in the oil and gas industry takes most of the well cost and how fast the drilling bit penetrate and bore the formation is termed the Rate of penetration (ROP). Since most of the cost incurred during drilling is related to the drilling operations, there is need not only to drill carefully, but also to optimize the drilling process. A lot of parameters are related to the rate of penetration which are actually interdependent on each other. This makes it difficult to predict the influence of every single parameter Drilling optimization techniques have been used recently to reduce drilling operation costs. There are different approaches to optimizing the cost of drilling oil and gas wells, some of which include static and /or real time optimization of drilling parameters. A potential area for optimization of drilling cost is through bit run in the well but this is particularly difficult due to its significance in both drilling time and bit cost. In this sense, as a particular bit gets used, it gets dull as its footage increases, resulting from the reduction in the bit penetration rate. The reduction in penetration rate increases total drill time. In order to optimize bit cost, it is desirable to find a trade-off between the two by a bit change policy This study is aimed at minimizing drilling time by use of artificial intelligent for the bit program. Data obtained from a well in the Niger delta region of Nigeria was used in this study and the cost optimization modelled as a Markov decision process where the intelligent agent was to learn the optimal timings for bit change by reinforcement policy Iteration learning. This study was able to achieve its objectives as the reinforcement learning optimization process performed very well with time as the computer agent was able to figure out how to improve drilling cost over time. Better results could be obtained with a better hardware and increased training time.","PeriodicalId":282073,"journal":{"name":"Petroleum & Petrochemical Engineering Journal","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131239994","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}
We are currently witnessing a high-rate of exploitation of oil fields at the stage of declining production. This decline is a result of the depletion of oil fields, which leads to the use of electric submersible centrifugal pumps (ESP) with dynamic head below saturation pressure. In this operating mode, the ESP’s efficiency deteriorates, leading to the overheating of its working elements during operation. The boiling of water contained in the wellstream and salt deposition can take place in an overheated pump. This, in turn, can lead to a premature failure of the centrifugal pump and reduce the economic viability of this oil production method. To eliminate premature failure, such units must be transferred to an operating mode with periodic shutdowns. Yet, the planning of trip-out and restart time schedules is performed in the absence of a proper theoretical justification. Such planning often leads to ESP failures due to the reduction of the electric resistance of cable lines or salt deposition. To prevent salt deposition, oil production companies use different chemicals, which are pumped into the hole annulus and are expected to stop salt deposition when propelled into the pump pot. Chemical treatment practice shows that these reagents perform poorly and may not prevent salt deposition at all. In reality, chemical compounds can damage downhole equipment and its structural elements. Long-term use of these reagents may lead to ecological disaster – the contamination of productive formations and confined groundwater beds. This work investigates the possibility of ESP operation in periodic mode without salt deposition and the exploitation of oil fields without the application of chemical reagents. The development of a periodic operation method allowing for ESP operation without salt deposition could eliminate the use of reagents in oil production and thereby reduce the risk of ecological disasters.
{"title":"Environmental Issues of Transient Behavior","authors":"Gareev Aa","doi":"10.23880/ppej-16000284","DOIUrl":"https://doi.org/10.23880/ppej-16000284","url":null,"abstract":"We are currently witnessing a high-rate of exploitation of oil fields at the stage of declining production. This decline is a result of the depletion of oil fields, which leads to the use of electric submersible centrifugal pumps (ESP) with dynamic head below saturation pressure. In this operating mode, the ESP’s efficiency deteriorates, leading to the overheating of its working elements during operation. The boiling of water contained in the wellstream and salt deposition can take place in an overheated pump. This, in turn, can lead to a premature failure of the centrifugal pump and reduce the economic viability of this oil production method. To eliminate premature failure, such units must be transferred to an operating mode with periodic shutdowns. Yet, the planning of trip-out and restart time schedules is performed in the absence of a proper theoretical justification. Such planning often leads to ESP failures due to the reduction of the electric resistance of cable lines or salt deposition. To prevent salt deposition, oil production companies use different chemicals, which are pumped into the hole annulus and are expected to stop salt deposition when propelled into the pump pot. Chemical treatment practice shows that these reagents perform poorly and may not prevent salt deposition at all. In reality, chemical compounds can damage downhole equipment and its structural elements. Long-term use of these reagents may lead to ecological disaster – the contamination of productive formations and confined groundwater beds. This work investigates the possibility of ESP operation in periodic mode without salt deposition and the exploitation of oil fields without the application of chemical reagents. The development of a periodic operation method allowing for ESP operation without salt deposition could eliminate the use of reagents in oil production and thereby reduce the risk of ecological disasters.","PeriodicalId":282073,"journal":{"name":"Petroleum & Petrochemical Engineering Journal","volume":"106 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116373493","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 constant focus of the public and media on oil spill pollution in the environment has led to a forced improvement in its clean-up process. But these methods are not as effective and efficient as society and the environment requires them to be. One of the major reasons for this is that an oil spill does not contain uniform distribution of the oil over an area, neither are the microorganisms present evenly distributed in the environment. However, when it is not possible for fiscal and any technical reasons to bring about ecosystem restoration, the obvious strategy is to prevent the discharge of pollutants. When this is not possible and crude oil (or heavy oil) has already been introduced to the environment, there is the potential for the Earth to heal itself and introduce balance over time. What is necessary as a society is to harness these natural methods and ensure that oil spills are contained in the shortest time possible.
{"title":"A Feasibility Study of Natural Attenuation as a Viable Cleanup Method for Heavy Oil Spills","authors":"Speight Jg, Karuna K. Arjoon","doi":"10.23880/ppej-16000294","DOIUrl":"https://doi.org/10.23880/ppej-16000294","url":null,"abstract":"The constant focus of the public and media on oil spill pollution in the environment has led to a forced improvement in its clean-up process. But these methods are not as effective and efficient as society and the environment requires them to be. One of the major reasons for this is that an oil spill does not contain uniform distribution of the oil over an area, neither are the microorganisms present evenly distributed in the environment. However, when it is not possible for fiscal and any technical reasons to bring about ecosystem restoration, the obvious strategy is to prevent the discharge of pollutants. When this is not possible and crude oil (or heavy oil) has already been introduced to the environment, there is the potential for the Earth to heal itself and introduce balance over time. What is necessary as a society is to harness these natural methods and ensure that oil spills are contained in the shortest time possible.","PeriodicalId":282073,"journal":{"name":"Petroleum & Petrochemical Engineering Journal","volume":"91 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131760816","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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