In order to study the basic superconductivity properties of R2Pt3Ge5, we synthesized the single crystalline samples by the Pt–Ge self-flux method. R2Pt3Ge5（R = La, Ce） were also grown for a systematic study. Zero-r...In order to study the basic superconductivity properties of R2Pt3Ge5, we synthesized the single crystalline samples by the Pt–Ge self-flux method. R2Pt3Ge5（R = La, Ce） were also grown for a systematic study. Zero-resistivity was observed in both the La-and Pr-based samples below the reported superconducting transition temperatures. However, magnetic susceptibility measurements showed low superconductivity volume fractions in both La2Pt3Ge5 and R2Pt3Ge5（less than2%）. Ce2Pt3Ge5 did not show any signature of superconductivity. From the specific heat measurements, we did not observe a superconducting transition peak in R2Pt3Ge5, suggesting that it is not a bulk superconductor. The magnetic susceptibility and heat capacity measurements revealed two antiferromagnetic（AFM） orders in R2Pt3Ge5 at T（N1）= 4.2 K and T（N2）= 3.5K, as well as a single AFM transition at TN= 3.8 K in Ce2Pt3Ge5.展开更多
A new practical method is introduced to transform the stateful transitive signature scheme to stateless one with-out the loss of security.According to the approach,two concrete stateless transitive signature schemes b...A new practical method is introduced to transform the stateful transitive signature scheme to stateless one with-out the loss of security.According to the approach,two concrete stateless transitive signature schemes based on Factoringand RSA are presented respectively.Under the assumption of the hardness of factoring and one-more-RSA-inversion prob-lem,both two schemes are secure under the adaptive chosen-message attacks in random oracle model.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.11204041)STCSM of China(Grant No.15XD1500200)
文摘In order to study the basic superconductivity properties of R2Pt3Ge5, we synthesized the single crystalline samples by the Pt–Ge self-flux method. R2Pt3Ge5（R = La, Ce） were also grown for a systematic study. Zero-resistivity was observed in both the La-and Pr-based samples below the reported superconducting transition temperatures. However, magnetic susceptibility measurements showed low superconductivity volume fractions in both La2Pt3Ge5 and R2Pt3Ge5（less than2%）. Ce2Pt3Ge5 did not show any signature of superconductivity. From the specific heat measurements, we did not observe a superconducting transition peak in R2Pt3Ge5, suggesting that it is not a bulk superconductor. The magnetic susceptibility and heat capacity measurements revealed two antiferromagnetic（AFM） orders in R2Pt3Ge5 at T（N1）= 4.2 K and T（N2）= 3.5K, as well as a single AFM transition at TN= 3.8 K in Ce2Pt3Ge5.
文摘A new practical method is introduced to transform the stateful transitive signature scheme to stateless one with-out the loss of security.According to the approach,two concrete stateless transitive signature schemes based on Factoringand RSA are presented respectively.Under the assumption of the hardness of factoring and one-more-RSA-inversion prob-lem,both two schemes are secure under the adaptive chosen-message attacks in random oracle model.
