To address the problem of identifying multiple types of additives in lubricating oil,a method based on midinfrared spectral band selection using the eXtreme Gradient Boosting(XGBoost)algorithm combined with the ant co...To address the problem of identifying multiple types of additives in lubricating oil,a method based on midinfrared spectral band selection using the eXtreme Gradient Boosting(XGBoost)algorithm combined with the ant colony optimization(ACO)algorithm is proposed.The XGBoost algorithm was used to train and test three additives,T534(alkyl diphenylamine),T308(isooctyl acid thiophospholipid octadecylamine),and T306(trimethylphenol phosphate),separately,in order to screen for the optimal combination of spectral bands for each additive.The ACO algorithm was used to optimize the parameters of the XGBoost algorithm to improve the identification accuracy.During this process,the support vector machine(SVM)and hybrid bat algorithms(HBA)were included as a comparison,generating four models:ACO-XGBoost,ACO-SVM,HBA-XGboost,and HBA-SVM.The results showed that all four models could identify the three additives efficiently,with the ACO-XGBoost model achieving 100%recognition of all three additives.In addition,the generalizability of the ACO-XGBoost model was further demonstrated by predicting a lubricating oil containing the three additives prepared in our laboratory and a collected sample of commercial oil currently in use。展开更多
China is expanding its scope in looking for energy resources in foreign assets,participating actively in the international oil and gas market to ensure the domestic supply driven by economic growth.In mid-November 201...China is expanding its scope in looking for energy resources in foreign assets,participating actively in the international oil and gas market to ensure the domestic supply driven by economic growth.In mid-November 2013,Sinopec Group,the country’s largest refiner,announced it has officially completed the acquisition of one-third of Apache Corp.’s Egypt oil and gas business.On Aug 30,Sinopec and Apache had launched a global strategic partnership,with the展开更多
This paper mainly studies on the performance of high-speed diesel engines and emission reduction when the engine uses heavy oil mixed with nanometer-sized additives Ce0.9 Cu0.1 O2 and Ce0.9 Zr0.1 O2.During the test,In...This paper mainly studies on the performance of high-speed diesel engines and emission reduction when the engine uses heavy oil mixed with nanometer-sized additives Ce0.9 Cu0.1 O2 and Ce0.9 Zr0.1 O2.During the test,Indiset 620 combustion analyzer made by AVL,was used to make a real-time survey on the cylinder pressure,the fuel ignition moment,and establish a relation between the change trend of temperature in cylinder and the crank angle.For the engine burning heavy oil and heavy oil mixed with additives,combustion analysis software Indicom and Concerto were used to analyze its combustion process and emission conditions.Experimental investigation shows that nano-sized complex oxide can improve the performance of diesel engine fueled with heavy oil,and reduce the emission of pollutants like NOx and CO,comparing it with the pure heavy oil.According to the consequences of this experiment,the additives improve the overall performance in the use of heavy oil.展开更多
Oleic acid surface-modified Cu nanoparticles with an average size of 20 nm were prepared by liquid phase reducing reaction. The tribological performance and mechanism of nanocopper as additive were studied by means of...Oleic acid surface-modified Cu nanoparticles with an average size of 20 nm were prepared by liquid phase reducing reaction. The tribological performance and mechanism of nanocopper as additive were studied by means of tribotester, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and nanoindentation instrument. The results indicate that the modified nanocopper additive can significantly improve the wear resistance and reduce friction coefficient of base oil. A copper protective film is formed and contributes to the excellent tribological properties of nanocopper additive. On the basis of the film forming mechanism, a new in-situ repair method was designed and used to repair wear-out-failure injection pump plunger and barrel. Furthermore, the current research progress of nanoparticles as green energy-saving lubricating oil additives were presented.展开更多
Diamond-like carbon(DLC)and graphite-like carbon(GLC)coatings have good prospects for improving the surface properties of engine parts.However,further understanding is needed on the effect of working conditions on tri...Diamond-like carbon(DLC)and graphite-like carbon(GLC)coatings have good prospects for improving the surface properties of engine parts.However,further understanding is needed on the effect of working conditions on tribological behaviors.In this study,GLC and two types of DLC coatings were deposited on GCr15 substrate for investigation.The friction and wear properties of self-mated and steel-mated pairs were evaluated.Two temperatures(25 and 90℃),three lubrication conditions(base oil,molybdenum dithiocarbamate(MoDTC)-containing oil,MoDTC+zinc dialkyldithiophosphate(ZDDP)-containing oil),and high Hertz contact stress(2.41 GPa)were applied in the experiments.The results showed that high temperature promoted the effect of ZDDP on steel-mated pairs,but increased wear under base oil lubrication.The increased wear for steel-mated pairs lubricated by MoDTC-containing oil was due to abrasive wear probably caused by MoO_(3) andβ-FeMoO_(4).It was also found that in most cases,the tribological properties of self-mated pairs were better than those of steel-mated pairs.展开更多
基金the Beijing Natural Science Foundation(Grant No.2232066)the Open Project Foundation of State Key Laboratory of Solid Lubrication(Grant LSL-2212).
文摘To address the problem of identifying multiple types of additives in lubricating oil,a method based on midinfrared spectral band selection using the eXtreme Gradient Boosting(XGBoost)algorithm combined with the ant colony optimization(ACO)algorithm is proposed.The XGBoost algorithm was used to train and test three additives,T534(alkyl diphenylamine),T308(isooctyl acid thiophospholipid octadecylamine),and T306(trimethylphenol phosphate),separately,in order to screen for the optimal combination of spectral bands for each additive.The ACO algorithm was used to optimize the parameters of the XGBoost algorithm to improve the identification accuracy.During this process,the support vector machine(SVM)and hybrid bat algorithms(HBA)were included as a comparison,generating four models:ACO-XGBoost,ACO-SVM,HBA-XGboost,and HBA-SVM.The results showed that all four models could identify the three additives efficiently,with the ACO-XGBoost model achieving 100%recognition of all three additives.In addition,the generalizability of the ACO-XGBoost model was further demonstrated by predicting a lubricating oil containing the three additives prepared in our laboratory and a collected sample of commercial oil currently in use。
文摘China is expanding its scope in looking for energy resources in foreign assets,participating actively in the international oil and gas market to ensure the domestic supply driven by economic growth.In mid-November 2013,Sinopec Group,the country’s largest refiner,announced it has officially completed the acquisition of one-third of Apache Corp.’s Egypt oil and gas business.On Aug 30,Sinopec and Apache had launched a global strategic partnership,with the
基金Supported by the Fundamental Research Funds for the Central Universities of China(DUT11NY09)
文摘This paper mainly studies on the performance of high-speed diesel engines and emission reduction when the engine uses heavy oil mixed with nanometer-sized additives Ce0.9 Cu0.1 O2 and Ce0.9 Zr0.1 O2.During the test,Indiset 620 combustion analyzer made by AVL,was used to make a real-time survey on the cylinder pressure,the fuel ignition moment,and establish a relation between the change trend of temperature in cylinder and the crank angle.For the engine burning heavy oil and heavy oil mixed with additives,combustion analysis software Indicom and Concerto were used to analyze its combustion process and emission conditions.Experimental investigation shows that nano-sized complex oxide can improve the performance of diesel engine fueled with heavy oil,and reduce the emission of pollutants like NOx and CO,comparing it with the pure heavy oil.According to the consequences of this experiment,the additives improve the overall performance in the use of heavy oil.
文摘Oleic acid surface-modified Cu nanoparticles with an average size of 20 nm were prepared by liquid phase reducing reaction. The tribological performance and mechanism of nanocopper as additive were studied by means of tribotester, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and nanoindentation instrument. The results indicate that the modified nanocopper additive can significantly improve the wear resistance and reduce friction coefficient of base oil. A copper protective film is formed and contributes to the excellent tribological properties of nanocopper additive. On the basis of the film forming mechanism, a new in-situ repair method was designed and used to repair wear-out-failure injection pump plunger and barrel. Furthermore, the current research progress of nanoparticles as green energy-saving lubricating oil additives were presented.
基金This work was supported by the Beijing Municipal Natural Science Foundation(3182032)the National Natural Science Foundation of China(41772389)+1 种基金the Pre-Research Program in National 13th Five-Year Plan(61409230603)Joint Fund of Ministry of Education for Pre-research of Equipment for Young Personnel Project(6141A02033120).
文摘Diamond-like carbon(DLC)and graphite-like carbon(GLC)coatings have good prospects for improving the surface properties of engine parts.However,further understanding is needed on the effect of working conditions on tribological behaviors.In this study,GLC and two types of DLC coatings were deposited on GCr15 substrate for investigation.The friction and wear properties of self-mated and steel-mated pairs were evaluated.Two temperatures(25 and 90℃),three lubrication conditions(base oil,molybdenum dithiocarbamate(MoDTC)-containing oil,MoDTC+zinc dialkyldithiophosphate(ZDDP)-containing oil),and high Hertz contact stress(2.41 GPa)were applied in the experiments.The results showed that high temperature promoted the effect of ZDDP on steel-mated pairs,but increased wear under base oil lubrication.The increased wear for steel-mated pairs lubricated by MoDTC-containing oil was due to abrasive wear probably caused by MoO_(3) andβ-FeMoO_(4).It was also found that in most cases,the tribological properties of self-mated pairs were better than those of steel-mated pairs.
