Calculations and analyses are made for the ultimate composition of 158 Chinese power coals. The results reveal that the carbon content on as received basis, Cr, increases linearly with the increase of the low heating ...Calculations and analyses are made for the ultimate composition of 158 Chinese power coals. The results reveal that the carbon content on as received basis, Cr, increases linearly with the increase of the low heating value Qnot,a, on as received basis; the hydrogen content on as received basis, Hr, first increases with the increase of the volatile content on dry ash free basis Vdaf （Vdaf 〈 33.0%） and then decreases （Vdaf 〉 33.0%）; the oxygen content on as received basis, Oar, increases linearly with the increase of Vau, ranging between 2.0% and 12.5%. By comparison, the nitrogen content on as received basis N of bituminous and lean coal is higher, while the sulfur content on as received basis Sar Of anthracite is higher than bituminous coal, lean coal and lignite. The hydrogen on as received basis Hr is important for the conversion between low heating value and high heating value on as received basis for Chinese power coals, and Sr is important for the calculation of high heating value from the oxygen bomb heat value for Chinese power coals.展开更多
The influences of Tropical Rainfall Measuring Mission （TRMM） precipitation products on the structure and underlying physics of intraseasonal oscillation （ISO） are investigated with the U.S. National Aeronautics an...The influences of Tropical Rainfall Measuring Mission （TRMM） precipitation products on the structure and underlying physics of intraseasonal oscillation （ISO） are investigated with the U.S. National Aeronautics and Space Administration Goddard Earth Observing System model version 3 （GEOS-3） data assimilation system （DAS）. The strong ISO phase in the 1998 summer is apparently located in the Asian monsoon region and the east equatorial Pacific region. The eastward propagation is a dominant feature for the tropical ISO at 20 to 30-day oscillation while the northeastward propagation is the salient ISO at 30 to 60-day oscillation over the 10~N to 25~N belt region. It appears that the Kelvin wave structure is for the tropical 20 to 30-day oscillation. The tropical 30 to 60-day oscillation has the characteristics of the Kelvin-Rossby wave. The impact of satellite-derived precipitation （and its associated latent heating） on the ISO intensity is limited in the GEOS-3 assimilation system. However, its impact on the ISO spatial structures is obvious. Overall, the results demonstrate a better eastward propagation and a northward propagation of ISO with the TRMM precipitation simulation, indicating that latent heating is very important in exciting the equatorial ISO. Key words： 20 to 30-day oscillation; 30 to 60-day oscillation; GEOS data assimilation system; Kelvin wave; TRMM precipitation展开更多
In the wireless power transfer system for freely moving biomedical implants,the receiving unit was generally inefficient for the reason that its design parameters including the receiving coil's dimension and recei...In the wireless power transfer system for freely moving biomedical implants,the receiving unit was generally inefficient for the reason that its design parameters including the receiving coil's dimension and receiving circuits' topology were always determined by experiments.In order to build the relationship between these parameters and the total transfer efficiency,this paper developed a novel efficiency model based on the impedance model of the coil and the circuit model of the receiving circuits.According to the design constraints,the optimal design parameters in the worst case were derived.The results indicate that the combination of the two-layered receiving coil and half-bridge rectifier has more advantages in size,efficiency and safety,which is preferred in the receiving unit.Additionally,when the load resistance increases,the optimal turn number of the receiving coil basically keeps constant and the corresponding transmitting current and total efficiency decrease.For 100 Ω load,the transmitting current and total efficiency in the worst case were measured to be 5.30 A and 1.45% respectively,which are much better than the published results.In general,our work provides an efficient method to determine the design parameters of the wireless power transfer system for freely moving biomedical implants.展开更多
文摘Calculations and analyses are made for the ultimate composition of 158 Chinese power coals. The results reveal that the carbon content on as received basis, Cr, increases linearly with the increase of the low heating value Qnot,a, on as received basis; the hydrogen content on as received basis, Hr, first increases with the increase of the volatile content on dry ash free basis Vdaf （Vdaf 〈 33.0%） and then decreases （Vdaf 〉 33.0%）; the oxygen content on as received basis, Oar, increases linearly with the increase of Vau, ranging between 2.0% and 12.5%. By comparison, the nitrogen content on as received basis N of bituminous and lean coal is higher, while the sulfur content on as received basis Sar Of anthracite is higher than bituminous coal, lean coal and lignite. The hydrogen on as received basis Hr is important for the conversion between low heating value and high heating value on as received basis for Chinese power coals, and Sr is important for the calculation of high heating value from the oxygen bomb heat value for Chinese power coals.
基金Qing Lan Project and a Special Public Sector Research (GYHY200806009)The second author was funded by the NASA Global Water and Energy Cycle project with a grant NNG04G098G
文摘The influences of Tropical Rainfall Measuring Mission （TRMM） precipitation products on the structure and underlying physics of intraseasonal oscillation （ISO） are investigated with the U.S. National Aeronautics and Space Administration Goddard Earth Observing System model version 3 （GEOS-3） data assimilation system （DAS）. The strong ISO phase in the 1998 summer is apparently located in the Asian monsoon region and the east equatorial Pacific region. The eastward propagation is a dominant feature for the tropical ISO at 20 to 30-day oscillation while the northeastward propagation is the salient ISO at 30 to 60-day oscillation over the 10~N to 25~N belt region. It appears that the Kelvin wave structure is for the tropical 20 to 30-day oscillation. The tropical 30 to 60-day oscillation has the characteristics of the Kelvin-Rossby wave. The impact of satellite-derived precipitation （and its associated latent heating） on the ISO intensity is limited in the GEOS-3 assimilation system. However, its impact on the ISO spatial structures is obvious. Overall, the results demonstrate a better eastward propagation and a northward propagation of ISO with the TRMM precipitation simulation, indicating that latent heating is very important in exciting the equatorial ISO. Key words： 20 to 30-day oscillation; 30 to 60-day oscillation; GEOS data assimilation system; Kelvin wave; TRMM precipitation
基金supported by the National Natural Science Foundation of China(Grant No.61473281)the National Sciences and Technology Support Project(Grant No.2015BAI01B13)State Key Laboratory of Robotics Self-plan Project(Grant No.2016-Z06)
文摘In the wireless power transfer system for freely moving biomedical implants,the receiving unit was generally inefficient for the reason that its design parameters including the receiving coil's dimension and receiving circuits' topology were always determined by experiments.In order to build the relationship between these parameters and the total transfer efficiency,this paper developed a novel efficiency model based on the impedance model of the coil and the circuit model of the receiving circuits.According to the design constraints,the optimal design parameters in the worst case were derived.The results indicate that the combination of the two-layered receiving coil and half-bridge rectifier has more advantages in size,efficiency and safety,which is preferred in the receiving unit.Additionally,when the load resistance increases,the optimal turn number of the receiving coil basically keeps constant and the corresponding transmitting current and total efficiency decrease.For 100 Ω load,the transmitting current and total efficiency in the worst case were measured to be 5.30 A and 1.45% respectively,which are much better than the published results.In general,our work provides an efficient method to determine the design parameters of the wireless power transfer system for freely moving biomedical implants.
