The load-carrying capacity, wear, and friction properties of four S-(1 H-Benzotriazol-1-yl)methyl N,N-dialkyldithiocarbamates added to a synthetic lubricant (diester) were evaluated using a four-ball test machine and an Optimal SRV tester. The results indicate that these compounds added to the diester possess good load-carrying capacities and antiwear properties. The rubbed surfaces were investigated using X-ray photoelectron spectroscopy (XPS) analysis and the antiwear mechanism is discussed.
采用四球试验机和Optimal SRV测试仪对添加到合成润滑剂(二酯)中的4种S-(1 h -苯并三唑-1-酰基)甲基N,N-二烷基二硫代氨基甲酸酯的承载能力、磨损性能和摩擦性能进行了评价。结果表明，加入到二酯中的这些化合物具有良好的承载能力和抗磨性能。利用x射线光电子能谱(XPS)对摩擦表面进行了研究，并对摩擦表面的抗磨机理进行了探讨。
{"title":"The tribological study of S‐(1H‐Benzotriazol‐1‐yl) methyl N,N‐dialkyldithiocarbamates as additives in synthetic lubricants","authors":"T. Ren, Q. Xue, Han-qing Wang","doi":"10.1002/JSL.3000110305","DOIUrl":"https://doi.org/10.1002/JSL.3000110305","url":null,"abstract":"The load-carrying capacity, wear, and friction properties of four S-(1 H-Benzotriazol-1-yl)methyl N,N-dialkyldithiocarbamates added to a synthetic lubricant (diester) were evaluated using a four-ball test machine and an Optimal SRV tester. The results indicate that these compounds added to the diester possess good load-carrying capacities and antiwear properties. The rubbed surfaces were investigated using X-ray photoelectron spectroscopy (XPS) analysis and the antiwear mechanism is discussed.","PeriodicalId":17149,"journal":{"name":"Journal of Synthetic Lubrication","volume":"17 6 1","pages":"207-214"},"PeriodicalIF":0.0,"publicationDate":"1994-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82887116","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}
Owing to growing environmental concerns, vegetable oils are finding their way into lubricants for industrial and transportation applications. Vegetable oils can of Ser significant environmental advantages with respect to resource renewability and biodegradability, as well as offering satisfactory performance in a variety of applications. Synthetic ester-based fluids may also offer these advantages, however their cost can be prohibitively high. Formulating with vegetable oil does, however, present unique challenges. These are, most notably, the oxidative and hydrolytic instability and low temperature problems associated with the triglyceride. However, through advanced plant breeding techniques, vegetable oils are becoming available which exhibit excellent thermal and oxidative stability and other improved performance properties. The cost of these oils is much lower than synthetic esters, thereby making them attractive ‘environmental’ base fluids.
{"title":"Performance testing of lubricants based on high oleic vegetable oils","authors":"K. Lal, Virginia A. Carrick","doi":"10.1002/JSL.3000110304","DOIUrl":"https://doi.org/10.1002/JSL.3000110304","url":null,"abstract":"Owing to growing environmental concerns, vegetable oils are finding their way into lubricants for industrial and transportation applications. Vegetable oils can of Ser significant environmental advantages with respect to resource renewability and biodegradability, as well as offering satisfactory performance in a variety of applications. Synthetic ester-based fluids may also offer these advantages, however their cost can be prohibitively high. Formulating with vegetable oil does, however, present unique challenges. These are, most notably, the oxidative and hydrolytic instability and low temperature problems associated with the triglyceride. However, through advanced plant breeding techniques, vegetable oils are becoming available which exhibit excellent thermal and oxidative stability and other improved performance properties. The cost of these oils is much lower than synthetic esters, thereby making them attractive ‘environmental’ base fluids.","PeriodicalId":17149,"journal":{"name":"Journal of Synthetic Lubrication","volume":"35 1","pages":"189-206"},"PeriodicalIF":0.0,"publicationDate":"1994-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76335740","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}
C. Snyder, L. Gschwender, G. Fultz, K. L. Paciorek, R. Kratzer
Low molecular weight chlorotrifluoroethylene (CTFE) oligomers have been the base fluid for an extensive DoD research and development programme for nonflammable hydraulic fluids, compatible elastomeric seals, components, and systems. To gain a more fundamental understanding of the effect of the specific isomers and other components of commercial CTFE fluids on the important fluid properties, model compounds were synthesised and their physical and chemical properties were determined. Thermal stability, in the presence of typical hardware system metals, is one of the more important properties and is discussed in relation to molecular structure. Two Microscale evaluation techniques were devised and validated. Optimum thermal stability is observed when the chlorines in the molecules are positioned as far apart as possible. In general, it was found that the compounds with larger amounts of chlorine were less stable and the positioning of the chlorine in the molecule had a lesser, but measurable effect.
{"title":"Structure–property relationships of model chlorstrifluoroethylene oligomer compounds: Thermal stability","authors":"C. Snyder, L. Gschwender, G. Fultz, K. L. Paciorek, R. Kratzer","doi":"10.1002/JSL.3000110302","DOIUrl":"https://doi.org/10.1002/JSL.3000110302","url":null,"abstract":"Low molecular weight chlorotrifluoroethylene (CTFE) oligomers have been the base fluid for an extensive DoD research and development programme for nonflammable hydraulic fluids, compatible elastomeric seals, components, and systems. To gain a more fundamental understanding of the effect of the specific isomers and other components of commercial CTFE fluids on the important fluid properties, model compounds were synthesised and their physical and chemical properties were determined. Thermal stability, in the presence of typical hardware system metals, is one of the more important properties and is discussed in relation to molecular structure. Two Microscale evaluation techniques were devised and validated. Optimum thermal stability is observed when the chlorines in the molecules are positioned as far apart as possible. In general, it was found that the compounds with larger amounts of chlorine were less stable and the positioning of the chlorine in the molecule had a lesser, but measurable effect.","PeriodicalId":17149,"journal":{"name":"Journal of Synthetic Lubrication","volume":"52 1","pages":"163-176"},"PeriodicalIF":0.0,"publicationDate":"1994-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80640114","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. Martinella, S. Giovanardi, Lg. Palombarini, R. Giorgi
Owing to the great interest in the medical field in the tribological couple UHMWPE–Ti6Al4V, its wear behaviour was studied and compared to that displayed by the more typical couples of UHMWPE–AISI 316 and UHMWPE–Vitallium. The Ti6Al4V alloy was given three different surface treatments: (a) a conventional lapping procedure; (b) a special lapping procedure; (c) nitrogen ion-implantation at 873°K. The last two samples induced, on a UHMWPE countetace, a wear rate lower than a factor of 10 compared to diamond lapped specimens; their behaviour was also better than the couples UHMWPE–AISI and UHMWPE–Vitallium. Wear improvement was attributed to the reduction of polymer transfer and adhesion on the metal counterface, due to the reduction of adhesive affinity between UHMWPE and the metal following surface treatment of the metal. The results are interpreted on the grounds of TEM and AES analyses.
{"title":"Improvement of the wear behaviour of the couple UHMWPE–Ti6A14V through surface treatments","authors":"R. Martinella, S. Giovanardi, Lg. Palombarini, R. Giorgi","doi":"10.1002/JSL.3000110303","DOIUrl":"https://doi.org/10.1002/JSL.3000110303","url":null,"abstract":"Owing to the great interest in the medical field in the tribological couple UHMWPE–Ti6Al4V, its wear behaviour was studied and compared to that displayed by the more typical couples of UHMWPE–AISI 316 and UHMWPE–Vitallium. \u0000 \u0000 \u0000 \u0000The Ti6Al4V alloy was given three different surface treatments: (a) a conventional lapping procedure; (b) a special lapping procedure; (c) nitrogen ion-implantation at 873°K. The last two samples induced, on a UHMWPE countetace, a wear rate lower than a factor of 10 compared to diamond lapped specimens; their behaviour was also better than the couples UHMWPE–AISI and UHMWPE–Vitallium. \u0000 \u0000 \u0000 \u0000Wear improvement was attributed to the reduction of polymer transfer and adhesion on the metal counterface, due to the reduction of adhesive affinity between UHMWPE and the metal following surface treatment of the metal. The results are interpreted on the grounds of TEM and AES analyses.","PeriodicalId":17149,"journal":{"name":"Journal of Synthetic Lubrication","volume":"5 1","pages":"177-187"},"PeriodicalIF":0.0,"publicationDate":"1994-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76789810","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}
Neutral phosphate esters are used as fire-resistant basestocks in several applications including hydraulic systems, turbines, and compressors. They are also used as grease basestocks, and in hydrocarbon-based lubricants and synthetic fluids as antiwear additives. Development aspects of a new synthetic triaryl phosphate ester is presented in this paper. This product provides superior hydrolytic stability and lower volatility than existing commercial phosphate esters. Additionally, it has excellent oxidative stability and is fire resistant. The performance characteristics of the fluid suggest use of this phosphate ester as a high stability antiwear additive or lubricant basestock, and in any application where stability is of primary importance.
{"title":"A new high-stability synthetic phosphate ester","authors":"S. Shankwalkar, D. Placek","doi":"10.1002/JSL.3000110205","DOIUrl":"https://doi.org/10.1002/JSL.3000110205","url":null,"abstract":"Neutral phosphate esters are used as fire-resistant basestocks in several applications including hydraulic systems, turbines, and compressors. They are also used as grease basestocks, and in hydrocarbon-based lubricants and synthetic fluids as antiwear additives. \u0000 \u0000 \u0000 \u0000Development aspects of a new synthetic triaryl phosphate ester is presented in this paper. This product provides superior hydrolytic stability and lower volatility than existing commercial phosphate esters. Additionally, it has excellent oxidative stability and is fire resistant. The performance characteristics of the fluid suggest use of this phosphate ester as a high stability antiwear additive or lubricant basestock, and in any application where stability is of primary importance.","PeriodicalId":17149,"journal":{"name":"Journal of Synthetic Lubrication","volume":"60 1","pages":"121-128"},"PeriodicalIF":0.0,"publicationDate":"1994-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83292084","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}
Natural and synthetic lubricants specially formulated for cold rolling of aluminium were evaluated in terms of their ability to lower mill loads. The use of additives was also studied. Roll separating forces and roll torques were monitored. No significant differences between natural and synthetic oils were observed. The ability to maintain lubricant action was found to be lowest when synthetic esters were present, either in the base oil or as an additive.
{"title":"Use of lubricants during cold rolling of aluminium","authors":"S. Zhang, J. Lenard","doi":"10.1002/JSL.3000110203","DOIUrl":"https://doi.org/10.1002/JSL.3000110203","url":null,"abstract":"Natural and synthetic lubricants specially formulated for cold rolling of aluminium were evaluated in terms of their ability to lower mill loads. The use of additives was also studied. Roll separating forces and roll torques were monitored. No significant differences between natural and synthetic oils were observed. The ability to maintain lubricant action was found to be lowest when synthetic esters were present, either in the base oil or as an additive.","PeriodicalId":17149,"journal":{"name":"Journal of Synthetic Lubrication","volume":"14 1","pages":"99-109"},"PeriodicalIF":0.0,"publicationDate":"1994-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81952031","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}
Tribological characteristics of three PFPE's (Fomblin Z, Demnum, and Krytox) were studied under high vacuum using a four-ball apparatus with 440C steel specimens. Fomblin Z and Demnum exhibited initial scuffing-like high friction whereas Krytox did not. Steady state friction with Fomblin Z was the lowest among the three oils. Frictional values for Demnum and Krytox were almost the same. The lowest wear rate in air was provided by Krytox regardless of load, and low wear rates in vacuum at high load were achieved with Krytox and Demnum. Results are explained by reactivity and pressure-viscosity characteristics of the oils.
{"title":"Tribological characteristics of Perfluoropolyether liquid lubricants under sliding conditions in high vacuum","authors":"M. Masuko, W. Jones, L. Helmick","doi":"10.1002/JSL.3000110204","DOIUrl":"https://doi.org/10.1002/JSL.3000110204","url":null,"abstract":"Tribological characteristics of three PFPE's (Fomblin Z, Demnum, and Krytox) were studied under high vacuum using a four-ball apparatus with 440C steel specimens. Fomblin Z and Demnum exhibited initial scuffing-like high friction whereas Krytox did not. Steady state friction with Fomblin Z was the lowest among the three oils. Frictional values for Demnum and Krytox were almost the same. The lowest wear rate in air was provided by Krytox regardless of load, and low wear rates in vacuum at high load were achieved with Krytox and Demnum. Results are explained by reactivity and pressure-viscosity characteristics of the oils.","PeriodicalId":17149,"journal":{"name":"Journal of Synthetic Lubrication","volume":"1 1","pages":"111-119"},"PeriodicalIF":0.0,"publicationDate":"1994-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89020496","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 use of synthetic, biodegradable lubricants for two-stroke engines has become widespread due to increased concern over the build-up of hydrocarbons, derived from mineral oil-based lubricants, in the aquatic environment. A method for assessing the biodegradation potential of new lubricants was developed by the Co-ordinating European Council (CEC) for the Development of Performance Tests for Lubricants and Engine Fuels in 1982. However, this method deals only with the aquatic environment. The use of such lubricants in agricultural machinery led to a modification of the CEC method to assess the relative biodegradability of lubricants in soil. After incubation of oil-treated soil in a simple and inexpensive incubation assembly, samples were extracted with solvent and the level of lubricant determined by infrared spectroscopy. The method was found to be both accurate and reproducible, giving excellent recoveries. It compared favourably with a gravimetric method and was so sensitive that it gave appreciable blank values from untreated soils owing to their content of long chain aliphatic natural products. The incubation and extraction methods were used successfully to assess the biodegradability of a range of synthetic lubricants in soil in comparison to a mineral oil-based lubricant and a natural vegetable oil. The synthetic oils were found to degrade more rapidly and extensively than the mineral oil-based lubricant but not as rapidly or extensively as the vegetable oil. Amendment with nitrate considerably enhanced the loss of all the oil tested, indicating the importance of nitrogen availability when assessing the inherent biodegradability of hydrocarbons in soil. As the data generated is from laboratory-based studies the results do not necessarily translate directly to the field situation. However, the method is suitable for screening new materials and for comparative purposes.
{"title":"Determination of synthetic lubricant concentrations in soil during laboratory‐based biodegradation studies","authors":"S. D. Haigh","doi":"10.1002/JSL.3000110202","DOIUrl":"https://doi.org/10.1002/JSL.3000110202","url":null,"abstract":"The use of synthetic, biodegradable lubricants for two-stroke engines has become widespread due to increased concern over the build-up of hydrocarbons, derived from mineral oil-based lubricants, in the aquatic environment. A method for assessing the biodegradation potential of new lubricants was developed by the Co-ordinating European Council (CEC) for the Development of Performance Tests for Lubricants and Engine Fuels in 1982. However, this method deals only with the aquatic environment. The use of such lubricants in agricultural machinery led to a modification of the CEC method to assess the relative biodegradability of lubricants in soil. After incubation of oil-treated soil in a simple and inexpensive incubation assembly, samples were extracted with solvent and the level of lubricant determined by infrared spectroscopy. The method was found to be both accurate and reproducible, giving excellent recoveries. It compared favourably with a gravimetric method and was so sensitive that it gave appreciable blank values from untreated soils owing to their content of long chain aliphatic natural products. The incubation and extraction methods were used successfully to assess the biodegradability of a range of synthetic lubricants in soil in comparison to a mineral oil-based lubricant and a natural vegetable oil. The synthetic oils were found to degrade more rapidly and extensively than the mineral oil-based lubricant but not as rapidly or extensively as the vegetable oil. Amendment with nitrate considerably enhanced the loss of all the oil tested, indicating the importance of nitrogen availability when assessing the inherent biodegradability of hydrocarbons in soil. As the data generated is from laboratory-based studies the results do not necessarily translate directly to the field situation. However, the method is suitable for screening new materials and for comparative purposes.","PeriodicalId":17149,"journal":{"name":"Journal of Synthetic Lubrication","volume":"31 1","pages":"83-98"},"PeriodicalIF":0.0,"publicationDate":"1994-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86576966","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}
Synthesised lubricant base stocks and the performance additives used in hypoid gear lubricants can both be chemically designed to give improved hypoid gear efficiency and, therefore, better vehicle fuel economy than provided by conventional lubricants In this paper, the authors review, relative to a widely used SAE 90 grade mineral oil-based lubricant, the changes in gear efficiency which have been documented using certain classes of synthesised lubricants. These advantages are described in terms of (a) EPA City and Highway Cycle efficiencies, (b) absolute data over a wide temperature range under four selected speed/torque combinations, and (c) absolute changes in inefficiency compared to the mineral oil product. Newtonian and non-Newtonian fluids have been studied. The bulk oil temperature at which a specific lubricant gives maximum efficiency is dependent on both gear operating conditions and on the chemical composition of the lubricant.
{"title":"The design of fuel efficient automotive hypoid gear lubricants","authors":"D. Law, C. N. Rowe","doi":"10.1002/JSL.3000110102","DOIUrl":"https://doi.org/10.1002/JSL.3000110102","url":null,"abstract":"Synthesised lubricant base stocks and the performance additives used in hypoid gear lubricants can both be chemically designed to give improved hypoid gear efficiency and, therefore, better vehicle fuel economy than provided by conventional lubricants \u0000 \u0000 \u0000 \u0000In this paper, the authors review, relative to a widely used SAE 90 grade mineral oil-based lubricant, the changes in gear efficiency which have been documented using certain classes of synthesised lubricants. These advantages are described in terms of (a) EPA City and Highway Cycle efficiencies, (b) absolute data over a wide temperature range under four selected speed/torque combinations, and (c) absolute changes in inefficiency compared to the mineral oil product. \u0000 \u0000 \u0000 \u0000Newtonian and non-Newtonian fluids have been studied. The bulk oil temperature at which a specific lubricant gives maximum efficiency is dependent on both gear operating conditions and on the chemical composition of the lubricant.","PeriodicalId":17149,"journal":{"name":"Journal of Synthetic Lubrication","volume":"17 1","pages":"1-15"},"PeriodicalIF":0.0,"publicationDate":"1994-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82413666","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}
As an alternative to tapping torque measurement and thread finish evaluation, a reaming test is suggested for the evaluation of the lubricating efficiency of cutting fluids. An investigation was carried out where results from tapping torque measurements were compared with those from measuring torque, feed force, and surface roughness in reaming. Two different tap geometries and two different reamer geometries were used. Technically-pure aluminium was used as the workpiece material and four laboratory water-based cutting fluids as well as a commercial cutting oil were investigated. The results show that lubricants have a significant and similar effect with respect to both tapping torque and reaming torque, when tools with straight flutes are used. In reaming, a more comprehensive picture of lubrication can be obtained if torque measurement is accompanied by determination of the surface roughness. In a subsequent investigation, the reaming torque and roughness test was used to evaluate two different water-based cutting fluids and a neat oil, using austenitic stainless steel as the workpiece material.
{"title":"A reaming test for cutting fluid evaluation","authors":"L. Chiffre, S. Lassen, K. B. Pedersen, S. Skade","doi":"10.1002/JSL.3000110103","DOIUrl":"https://doi.org/10.1002/JSL.3000110103","url":null,"abstract":"As an alternative to tapping torque measurement and thread finish evaluation, a reaming test is suggested for the evaluation of the lubricating efficiency of cutting fluids. An investigation was carried out where results from tapping torque measurements were compared with those from measuring torque, feed force, and surface roughness in reaming. Two different tap geometries and two different reamer geometries were used. Technically-pure aluminium was used as the workpiece material and four laboratory water-based cutting fluids as well as a commercial cutting oil were investigated. \u0000 \u0000The results show that lubricants have a significant and similar effect with respect to both tapping torque and reaming torque, when tools with straight flutes are used. In reaming, a more comprehensive picture of lubrication can be obtained if torque measurement is accompanied by determination of the surface roughness. In a subsequent investigation, the reaming torque and roughness test was used to evaluate two different water-based cutting fluids and a neat oil, using austenitic stainless steel as the workpiece material.","PeriodicalId":17149,"journal":{"name":"Journal of Synthetic Lubrication","volume":"64 1","pages":"17-34"},"PeriodicalIF":0.0,"publicationDate":"1994-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73143114","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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