Recent studies have shown that the La-and Y-hydrides can exhibit significant superconducting properties under high pressures.In this paper,we investigate the stability,electronic and superconducting properties of LaYH...Recent studies have shown that the La-and Y-hydrides can exhibit significant superconducting properties under high pressures.In this paper,we investigate the stability,electronic and superconducting properties of LaYH_(x)(x=2,3,6 and 8)under 0-200 GPa.It is found that LaYH_(2) stabilizes in the C2/m phase at ambient pressure,and transforms to the Pmmn phase at 67 GPa.LaYH_(3) stabilizes in the C2/m phase at ambient pressure,and undergoes phase transitions of C2/m→P2_(1)/m→R3m at 12 GPa and 87 GPa,respectively.LaYH_(6) stabilizes in the P4_32_12 phase at ambient pressure,and undergoes phase transitions of P4_(3)2_(1)2→P4/mmm→Cmcm at 28 GPa and 79 GPa,respectively.LaYH_(8) stabilizes in the Imma phase at 60 GPa and transforms to the P4/mmm phase at 117 GPa.Calculations of the electronic band structures show that the P4/mmm-LaYH_(8) and all phases of LaYH_(2) and LaYH_(3) exhibit metallic character.For the metallic phases,we then study their superconducting properties.The calculated superconducting transition temperatures(T_c)are 0.47 K for C2/m-LaYH_(2) at 0 GPa,0 K for C2/m-LaYH_(3) at 0 GPa,and 55.51 K for P4/mmm-LaYH_(8) at 50 GPa.展开更多
在探索厌氧处理制药产生的废渣和污水研究中,以中国A制药厂的药渣和中国B制药厂的污水为原料,研究制药废渣和污水的厌氧产气能力。结果表明:药渣TS产气率为205.6 m L/g^223.59 m L/g,VS产气率为221.3 m L/g^239.5 m L/g,有机物降解率为...在探索厌氧处理制药产生的废渣和污水研究中,以中国A制药厂的药渣和中国B制药厂的污水为原料,研究制药废渣和污水的厌氧产气能力。结果表明:药渣TS产气率为205.6 m L/g^223.59 m L/g,VS产气率为221.3 m L/g^239.5 m L/g,有机物降解率为40%左右,系统中不存在产气抑制物;制药污水的TS产气率为403.9 m L/g^409.2 m L/g,VS产气率为563.4 m L/g^578.6 m L/g,COD降解率85%以上。药渣沼气和污水沼气的CH4浓度分别为54.6%~60.7%和52.3%~56.8%。展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos.12364003,11804131,11704163,12375014,and 11875149)the Natural Science Foundation of Jiangxi Province of China (Grant Nos.20232BAB211022 and 20181BAB211007)。
文摘Recent studies have shown that the La-and Y-hydrides can exhibit significant superconducting properties under high pressures.In this paper,we investigate the stability,electronic and superconducting properties of LaYH_(x)(x=2,3,6 and 8)under 0-200 GPa.It is found that LaYH_(2) stabilizes in the C2/m phase at ambient pressure,and transforms to the Pmmn phase at 67 GPa.LaYH_(3) stabilizes in the C2/m phase at ambient pressure,and undergoes phase transitions of C2/m→P2_(1)/m→R3m at 12 GPa and 87 GPa,respectively.LaYH_(6) stabilizes in the P4_32_12 phase at ambient pressure,and undergoes phase transitions of P4_(3)2_(1)2→P4/mmm→Cmcm at 28 GPa and 79 GPa,respectively.LaYH_(8) stabilizes in the Imma phase at 60 GPa and transforms to the P4/mmm phase at 117 GPa.Calculations of the electronic band structures show that the P4/mmm-LaYH_(8) and all phases of LaYH_(2) and LaYH_(3) exhibit metallic character.For the metallic phases,we then study their superconducting properties.The calculated superconducting transition temperatures(T_c)are 0.47 K for C2/m-LaYH_(2) at 0 GPa,0 K for C2/m-LaYH_(3) at 0 GPa,and 55.51 K for P4/mmm-LaYH_(8) at 50 GPa.
文摘在探索厌氧处理制药产生的废渣和污水研究中,以中国A制药厂的药渣和中国B制药厂的污水为原料,研究制药废渣和污水的厌氧产气能力。结果表明:药渣TS产气率为205.6 m L/g^223.59 m L/g,VS产气率为221.3 m L/g^239.5 m L/g,有机物降解率为40%左右,系统中不存在产气抑制物;制药污水的TS产气率为403.9 m L/g^409.2 m L/g,VS产气率为563.4 m L/g^578.6 m L/g,COD降解率85%以上。药渣沼气和污水沼气的CH4浓度分别为54.6%~60.7%和52.3%~56.8%。
