In this paper, two types of silicon(Si) particles ball-milled from n-type Si wafers, respectively, with resistivity values of 1 Ω·cm and 0.001 Ω·cm are deposited with silver(Ag). The Ag-deposited n-typ...In this paper, two types of silicon(Si) particles ball-milled from n-type Si wafers, respectively, with resistivity values of 1 Ω·cm and 0.001 Ω·cm are deposited with silver(Ag). The Ag-deposited n-type 1-Ω·cm Si particles(nl-Ag) and Ag-deposited n-type 0.001-Ω·cm Si particles(n0.001-Ag) are separately used as an anode material to assemble coin cells,of which the electrochemical performances are investigated. For the matching of work function between n-type 1-Ω·cm Si(nl) and Ag, nl-Ag shows discharge specific capacity of up to 683 mAh·g^-1 at a current density of 8.4 A·g^-1, which is40% higher than that of n0.001-Ag. Furthermore, the resistivity of nl-Ag is lower than half that of n0.001-Ag. Due to the mismatch of work function between n-type 0.001-Ω·cm Si(n0.001) and Ag, the discharge specific capacity of n0.001-Ag is 250.2 mAh·g^-1 lower than that of nl-Ag after 100 cycles.展开更多
As the development tends towards high-speed, large-scale and high-power, power of the ship main engine becomes larger and larger. This make the engine design and cabin arrangement become more and more difficult. Ship ...As the development tends towards high-speed, large-scale and high-power, power of the ship main engine becomes larger and larger. This make the engine design and cabin arrangement become more and more difficult. Ship maneuverability becomes bad. A new ship propulsion system, integrated hydraulic propulsion (IHP), is put forward to meet the development of modem ship. Principle of IHP system is discussed. Working condition matching characteristic of IHP ship is studied based on its matching characteristic charts. According to their propulsion principle, dynamic mathematic models of IHP ship and direct propulsion (DP) ship are developed. These two models are verified by test sailing and test stand data. Based on the software Matlab/Simulink, comparison research between IHP ship and DP ship is conducted. The results show that cabin arrangement of IHP ship is very flexible, working condition matching characteristic of IHP ship is good, the ratio of power to weight of IHP ship is larger than DP ship, and maneuverability is excellent. IHP system is suitable for engineering ship, superpower ship and warship, etc.展开更多
SiGe is recognised as an excellent thermoelectric material with superior mechanical properties and thermal stability in regions with high temperatures.This study explores a novel strategy for coregulating thermoelectr...SiGe is recognised as an excellent thermoelectric material with superior mechanical properties and thermal stability in regions with high temperatures.This study explores a novel strategy for coregulating thermoelectric transport parameters to achieve high thermoelectric properties of p-type SiGe in the mid-temperature region by incorporating nano-TaC into SiGe combined ball milling with spark plasma sintering.By optimizing the amount of TaC in the SiGe matrix,the power factors were significantly increased due to the modulation doping effect based on the work function matching of SiGe with TaC.Simultaneously,the ensemble effect of the nanostructure leads to a significant decrease in thermal conductivity.Thus,a high ZT of 1.06 was accomplished at 873 K,which is 64%higher than that of typical radioisotope thermoelectric generator.Our research offers a novel strategy for expanding and enhancing the thermoelectric properties of SiGe materials in the medium temperature range.展开更多
基金Project supported by the China Postdoctoral Science Foundation(Grant No.2016M592115)the Jiangxi Postdoctoral Foundation,China(Grant No.2015KY12)+1 种基金the Fund from the Jiangxi Provincial Education Department,China(Grant No.150184)the Fund from Nanchang University,China(Grant No.CX2017006)
文摘In this paper, two types of silicon(Si) particles ball-milled from n-type Si wafers, respectively, with resistivity values of 1 Ω·cm and 0.001 Ω·cm are deposited with silver(Ag). The Ag-deposited n-type 1-Ω·cm Si particles(nl-Ag) and Ag-deposited n-type 0.001-Ω·cm Si particles(n0.001-Ag) are separately used as an anode material to assemble coin cells,of which the electrochemical performances are investigated. For the matching of work function between n-type 1-Ω·cm Si(nl) and Ag, nl-Ag shows discharge specific capacity of up to 683 mAh·g^-1 at a current density of 8.4 A·g^-1, which is40% higher than that of n0.001-Ag. Furthermore, the resistivity of nl-Ag is lower than half that of n0.001-Ag. Due to the mismatch of work function between n-type 0.001-Ω·cm Si(n0.001) and Ag, the discharge specific capacity of n0.001-Ag is 250.2 mAh·g^-1 lower than that of nl-Ag after 100 cycles.
基金supported by National Natural Science Foundation of China(Grant No. 50575027)Ministry of Transportation and Communications Foundation of China (Grant No. 200332922502)
文摘As the development tends towards high-speed, large-scale and high-power, power of the ship main engine becomes larger and larger. This make the engine design and cabin arrangement become more and more difficult. Ship maneuverability becomes bad. A new ship propulsion system, integrated hydraulic propulsion (IHP), is put forward to meet the development of modem ship. Principle of IHP system is discussed. Working condition matching characteristic of IHP ship is studied based on its matching characteristic charts. According to their propulsion principle, dynamic mathematic models of IHP ship and direct propulsion (DP) ship are developed. These two models are verified by test sailing and test stand data. Based on the software Matlab/Simulink, comparison research between IHP ship and DP ship is conducted. The results show that cabin arrangement of IHP ship is very flexible, working condition matching characteristic of IHP ship is good, the ratio of power to weight of IHP ship is larger than DP ship, and maneuverability is excellent. IHP system is suitable for engineering ship, superpower ship and warship, etc.
基金supported by National Key Research and Development Program of China(No.2017YFE0198000,2022YFE0119100).National Natural Science Foundation of China(Grant No.U21A2054,52273285,52061009,52262032).Guangxi Science and Technology Project(Grant No.AD21220056).
文摘SiGe is recognised as an excellent thermoelectric material with superior mechanical properties and thermal stability in regions with high temperatures.This study explores a novel strategy for coregulating thermoelectric transport parameters to achieve high thermoelectric properties of p-type SiGe in the mid-temperature region by incorporating nano-TaC into SiGe combined ball milling with spark plasma sintering.By optimizing the amount of TaC in the SiGe matrix,the power factors were significantly increased due to the modulation doping effect based on the work function matching of SiGe with TaC.Simultaneously,the ensemble effect of the nanostructure leads to a significant decrease in thermal conductivity.Thus,a high ZT of 1.06 was accomplished at 873 K,which is 64%higher than that of typical radioisotope thermoelectric generator.Our research offers a novel strategy for expanding and enhancing the thermoelectric properties of SiGe materials in the medium temperature range.