Rare-earth(RE)rich intermetallics crystallizing in orthorhombic Ho_(6)Co_(2)Ga-type crystal structure exhibit peculiar magnetic properties that are not widely reported for their magnetic ordering,order of magnetic pha...Rare-earth(RE)rich intermetallics crystallizing in orthorhombic Ho_(6)Co_(2)Ga-type crystal structure exhibit peculiar magnetic properties that are not widely reported for their magnetic ordering,order of magnetic phase transition,and related magnetocaloric behavior.By tuning the type of RE element in RE_(6)Co_(2)Ga(RE=Ho,Dy or Gd)compounds,metamagnetic anti-to-paramagnetic(AF to PM)phase transitions could be tuned to ferro-to-paramagnetic(FM to PM)phase transitions.Furthermore,the FM ground state for Gd_(6)Co_(2)Ga is confirmed by density functional theory calculations in addition to experimental observations.The field dependence magnetocaloric and Banerjee’s criteria demonstrate that Ho_(6)Co_(2)Ga and Dy_(6)Co_(2)Ga undergo a first-order phase transition in addition to a second-order phase transition,whereas only the latter is observed for Gd_(6)Co_(2)Ga.The two extreme alloys of the series,Ho_(6)Co_(2)Ga and Gd_(6)Co_(2)Ga,show maximum isothermal entropy change(|ΔS_(iso)^(max)(5T)|)of 10.1 and 9.1 J kg^(-1)K^(-1)at 26 and 75 K,close to H_(2)and N_(2)liquefaction,respectively.This outstanding magnetocaloric effect performance makes the RE6 Co_(2)Ga series of potential for cryogenic magnetic refrigeration applications.展开更多
The probability of long-range connection among neurons could be changeable in biological neuronal networks. In this paper, the probability of long-range connection between neurons is not fixed at a constant but varies...The probability of long-range connection among neurons could be changeable in biological neuronal networks. In this paper, the probability of long-range connection between neurons is not fixed at a constant but varies in a numerical region (≤p0 ), and then the collective behaviors of neurons are detected. A statistical factor in the two-dimensional space is used to detect the phase transition and robustness of spiral wave in the active network of neurons. It is found that the development of spatiotem-poral pattern depends on the numerical region (≤p0 ) for the probability of long-range connection. Coherence resonance-like behavior is observed due to the fluctuation in the long-range probability. Spiral waves emerge to occupy the network of neurons under an optimized probability of long-range connection, and it shows certain robustness in weak channel noise.展开更多
基金the National Natural Science Foundation of China(52071197)the Science and Technology Commission of Shanghai Municipality(19ZR1418300 and 19DZ2270200)+3 种基金AEI/FEDER-UE(PID2019-105720RB-I00)US/JUNTA/FEDER-UE(US-1260179)Consejería de Economía,Conocimiento,Empresas y Universidad de la Junta de Andalucía(P18-RT-746)the support provided by China Scholarship Council(CSC)of the Ministry of Education,China(202006890050)。
文摘Rare-earth(RE)rich intermetallics crystallizing in orthorhombic Ho_(6)Co_(2)Ga-type crystal structure exhibit peculiar magnetic properties that are not widely reported for their magnetic ordering,order of magnetic phase transition,and related magnetocaloric behavior.By tuning the type of RE element in RE_(6)Co_(2)Ga(RE=Ho,Dy or Gd)compounds,metamagnetic anti-to-paramagnetic(AF to PM)phase transitions could be tuned to ferro-to-paramagnetic(FM to PM)phase transitions.Furthermore,the FM ground state for Gd_(6)Co_(2)Ga is confirmed by density functional theory calculations in addition to experimental observations.The field dependence magnetocaloric and Banerjee’s criteria demonstrate that Ho_(6)Co_(2)Ga and Dy_(6)Co_(2)Ga undergo a first-order phase transition in addition to a second-order phase transition,whereas only the latter is observed for Gd_(6)Co_(2)Ga.The two extreme alloys of the series,Ho_(6)Co_(2)Ga and Gd_(6)Co_(2)Ga,show maximum isothermal entropy change(|ΔS_(iso)^(max)(5T)|)of 10.1 and 9.1 J kg^(-1)K^(-1)at 26 and 75 K,close to H_(2)and N_(2)liquefaction,respectively.This outstanding magnetocaloric effect performance makes the RE6 Co_(2)Ga series of potential for cryogenic magnetic refrigeration applications.
基金supported by the National Nature Science Foundation of China (Grant Nos.11265008 and 10972179)
文摘The probability of long-range connection among neurons could be changeable in biological neuronal networks. In this paper, the probability of long-range connection between neurons is not fixed at a constant but varies in a numerical region (≤p0 ), and then the collective behaviors of neurons are detected. A statistical factor in the two-dimensional space is used to detect the phase transition and robustness of spiral wave in the active network of neurons. It is found that the development of spatiotem-poral pattern depends on the numerical region (≤p0 ) for the probability of long-range connection. Coherence resonance-like behavior is observed due to the fluctuation in the long-range probability. Spiral waves emerge to occupy the network of neurons under an optimized probability of long-range connection, and it shows certain robustness in weak channel noise.
