The ionic liquid(IL) tributylmethylammonium bis(trifluoromethylsulfonyl)amide([N4441][NTf2]) was used as neat lubricant and as an additive(1.5 wt%) in a polar oil to study its friction and wear reducing properties.Tri...The ionic liquid(IL) tributylmethylammonium bis(trifluoromethylsulfonyl)amide([N4441][NTf2]) was used as neat lubricant and as an additive(1.5 wt%) in a polar oil to study its friction and wear reducing properties.Tribological tests were completed for 90 minutes at room temperature and 100 °C in a reciprocating configuration at loads of 30 and 70 N,10 Hz-frequency,and 4 mm stroke length.Wear volume was measured by confocal microscopy and the surface-IL interaction determined by XPS.The main findings were that neat IL showed the best tribological behavior;the IL-containing mixture behaved similar to the base oil regarding friction,however outperformed the antiwear behavior of the base oil under higher temperature;surface-IL chemical interaction was found mainly at 100 °C.展开更多
A previous modeling study about Pacific Ocean warming derived polar vortex response signals, by subtracting those in the Indian Ocean warming experiments from those in the Indo-Pacific. This approach questions the res...A previous modeling study about Pacific Ocean warming derived polar vortex response signals, by subtracting those in the Indian Ocean warming experiments from those in the Indo-Pacific. This approach questions the resemblance of such an indirectly derived response to one directly forced by Pacific Ocean warming. This is relevant to the additive nonlinearity of atmospheric responses to separated Indian and Pacific Ocean forcing. In the present study, an additional set of ensemble experiments are performed by prescribing isolated SST forcing in the tropical Pacific Ocean to address this issue. The results suggest a qualitative resemblance between responses in the derived and additional experiments. Thus, previous findings about the impact of Indian and Pacific Ocean wanning are robust. This study has important implications for future climate change projections, considering the non-unanimous warming rates in tropical oceans in the 21st century. Nevertheless, a comparison of present direct-forced experiments with previous indirect-forced experiments suggests a significant additive nonlinearity between the Indian and Pacific Ocean warmings. Further diagnosis suggests that the nonlinearity may originate from the thermodynamic processes over the tropics.展开更多
基金the Foundation for the Promotion in Asturias of the Applied Scientific Research and Technology(FICYT)and the Ministry of Economy and Competitiveness(Spain)for supporting this work in the framework of the research projects Lubrication and Surface Technology(GRUPIN14-023)STARLUBE(DPI2013-48348-C2-1-R)
文摘The ionic liquid(IL) tributylmethylammonium bis(trifluoromethylsulfonyl)amide([N4441][NTf2]) was used as neat lubricant and as an additive(1.5 wt%) in a polar oil to study its friction and wear reducing properties.Tribological tests were completed for 90 minutes at room temperature and 100 °C in a reciprocating configuration at loads of 30 and 70 N,10 Hz-frequency,and 4 mm stroke length.Wear volume was measured by confocal microscopy and the surface-IL interaction determined by XPS.The main findings were that neat IL showed the best tribological behavior;the IL-containing mixture behaved similar to the base oil regarding friction,however outperformed the antiwear behavior of the base oil under higher temperature;surface-IL chemical interaction was found mainly at 100 °C.
基金supported by the Special Fund for Meteorological Scientific Research in the Public Interest of China Meteorological Administration (Grant No. GYHY201006022)the Knowledge Innovation Program of the Chinese Academy of Sciences (Grant Nos. KZCX2-YW-BR-14 and KZCX2-YW-Q11-03)
文摘A previous modeling study about Pacific Ocean warming derived polar vortex response signals, by subtracting those in the Indian Ocean warming experiments from those in the Indo-Pacific. This approach questions the resemblance of such an indirectly derived response to one directly forced by Pacific Ocean warming. This is relevant to the additive nonlinearity of atmospheric responses to separated Indian and Pacific Ocean forcing. In the present study, an additional set of ensemble experiments are performed by prescribing isolated SST forcing in the tropical Pacific Ocean to address this issue. The results suggest a qualitative resemblance between responses in the derived and additional experiments. Thus, previous findings about the impact of Indian and Pacific Ocean wanning are robust. This study has important implications for future climate change projections, considering the non-unanimous warming rates in tropical oceans in the 21st century. Nevertheless, a comparison of present direct-forced experiments with previous indirect-forced experiments suggests a significant additive nonlinearity between the Indian and Pacific Ocean warmings. Further diagnosis suggests that the nonlinearity may originate from the thermodynamic processes over the tropics.