Constructing efficient carbon material with enhanced mass transfer ability from vacuum residuum(VR)is of prime industrial and scientific significance.Herein,we demonstrated a one-pot synthesis of metal-free and highly...Constructing efficient carbon material with enhanced mass transfer ability from vacuum residuum(VR)is of prime industrial and scientific significance.Herein,we demonstrated a one-pot synthesis of metal-free and highly symmetric hollow carbon cubes(HCCs)using cost-efficient vacuum residuum(VR)as a C/N/S source.By multi-techniques such as TEM,SEM,Raman,XPS,and XRD,it is found that the CTAB surfactant plays an important role in emulsifying and forming oil-in-water suspension particles.Subsequently,high aromatics contents in VR favor the formation of HCCs shell by graphitization on the surface of Na Cl template.Notably,heavy metals(e.g.,V,Ni)are not enriched in carbon skeleton due to the unique graphitization mechanism.This metal-free HCCs catalyst showed good catalytic stability and high selectivity towards direct and local electrochemical production of hydrogen peroxide(H_(2)O_(2))through two-electron O_(2)reduction due to enhanced mass transfer ability.The results provide a novel avenue to synthesize metal-free cubic carbon material from low-cost and plentiful VR,which are essential to the design of more efficient catalysts for O_(2)reduction to H_(2)O_(2).展开更多
This article refers to the first commercial application of upflow residuum hydrotreating serial catalyst, developed by Fushun Research Institute of Petroleum and Petrochemicals (FRIPP), in the residuum hydrotreating u...This article refers to the first commercial application of upflow residuum hydrotreating serial catalyst, developed by Fushun Research Institute of Petroleum and Petrochemicals (FRIPP), in the residuum hydrotreating unit at Shengli refinery of Qilu Petrochemical Company. This catalyst features large pore volume and large pore diameter. The production practice for more than one year has revealed that the domestic upflow residuum hydrotreating catalyst has shown good performance and stability over the whole period of operation despite its high activity at the start of run, and has basically reached the level of similar imported catalyst.展开更多
This paper examines the impact of fiscal residuum--the excess of expenditure benefits over tax burdens--on the location choice of foreign direct investments among China's provinces. Using data provided by the Nationa...This paper examines the impact of fiscal residuum--the excess of expenditure benefits over tax burdens--on the location choice of foreign direct investments among China's provinces. Using data provided by the National Bureau of Statistics of China we propose two fiscal residuum indexes for China's provinces over the period 1998-2004. According to Buchanan's original definition of fiscal residuum a first index is given by the difference between government expenditure and revenue. A second index measures enterprises' net fiscal benefit and is calculated as the difference between public expenditure that affect business activities and taxes paid by enterprises. We found that the first index does not significantly affect the FDI localization choice while the second one positively affects it. When looking at different subsets of provinces we found that for eastern provinces the first index has a positive and significant effect. These results confirm the role of the net fiscal benefit as a determinant of FDI inflows at the provincial level.展开更多
基金supported by the National Natural Science Foundation of China (21978325)。
文摘Constructing efficient carbon material with enhanced mass transfer ability from vacuum residuum(VR)is of prime industrial and scientific significance.Herein,we demonstrated a one-pot synthesis of metal-free and highly symmetric hollow carbon cubes(HCCs)using cost-efficient vacuum residuum(VR)as a C/N/S source.By multi-techniques such as TEM,SEM,Raman,XPS,and XRD,it is found that the CTAB surfactant plays an important role in emulsifying and forming oil-in-water suspension particles.Subsequently,high aromatics contents in VR favor the formation of HCCs shell by graphitization on the surface of Na Cl template.Notably,heavy metals(e.g.,V,Ni)are not enriched in carbon skeleton due to the unique graphitization mechanism.This metal-free HCCs catalyst showed good catalytic stability and high selectivity towards direct and local electrochemical production of hydrogen peroxide(H_(2)O_(2))through two-electron O_(2)reduction due to enhanced mass transfer ability.The results provide a novel avenue to synthesize metal-free cubic carbon material from low-cost and plentiful VR,which are essential to the design of more efficient catalysts for O_(2)reduction to H_(2)O_(2).
文摘This article refers to the first commercial application of upflow residuum hydrotreating serial catalyst, developed by Fushun Research Institute of Petroleum and Petrochemicals (FRIPP), in the residuum hydrotreating unit at Shengli refinery of Qilu Petrochemical Company. This catalyst features large pore volume and large pore diameter. The production practice for more than one year has revealed that the domestic upflow residuum hydrotreating catalyst has shown good performance and stability over the whole period of operation despite its high activity at the start of run, and has basically reached the level of similar imported catalyst.
文摘This paper examines the impact of fiscal residuum--the excess of expenditure benefits over tax burdens--on the location choice of foreign direct investments among China's provinces. Using data provided by the National Bureau of Statistics of China we propose two fiscal residuum indexes for China's provinces over the period 1998-2004. According to Buchanan's original definition of fiscal residuum a first index is given by the difference between government expenditure and revenue. A second index measures enterprises' net fiscal benefit and is calculated as the difference between public expenditure that affect business activities and taxes paid by enterprises. We found that the first index does not significantly affect the FDI localization choice while the second one positively affects it. When looking at different subsets of provinces we found that for eastern provinces the first index has a positive and significant effect. These results confirm the role of the net fiscal benefit as a determinant of FDI inflows at the provincial level.