Structural and magnetic properties of Nd15Fe70T15Nδ(T=V, Mo) alloys, made by mechanical alloying (MA) followed by heat-treatment and nitriding, have been investigated systematically.Effects of annealing temperature o...Structural and magnetic properties of Nd15Fe70T15Nδ(T=V, Mo) alloys, made by mechanical alloying (MA) followed by heat-treatment and nitriding, have been investigated systematically.Effects of annealing temperature on the structure and magnetic properties of the materials were studied by means of X-ray diffraction, AC susceptibility and high field magnetization measurements. Under pure argon atmosphere, the optimum temperatures for the heat treatment are found to be 75 and 850℃ for Nd15Fe7015Nδ and Nd15Fe70Mo15Nδ respectively. Correspondingly, the following magnetic properties are achieved : (1) Nd15Fe70V15Nδ:Br=0.63 T,,HC=8.01kA/cm (10.1 kOe), (BH )max=50.3 kJ/m3 (6 32 MGOe), (2) Nd15Fe70Mo15Nδ :Br=0.42 T. iHc=5.6 kA/cm (7.4 kOe), (BH )max=26.6 kJ/m3 (3.34 MGOe)展开更多
Background and Aims:Timely and effective assessment scoring systems for predicting the mortality of patients with hepatitis E virus-related acute liver failure(HEV-ALF)are urgently needed.The present study aimed to es...Background and Aims:Timely and effective assessment scoring systems for predicting the mortality of patients with hepatitis E virus-related acute liver failure(HEV-ALF)are urgently needed.The present study aimed to establish an effective nomogram for predicting the mortality of HEV-ALF patients.Methods:The nomogram was based on a cross-sectional set of 404 HEV-ALF patients who were identified and enrolled from a cohort of 650 patients with liver failure.To compare the performance with that of the model for end-stage liver disease(MELD)scoring and CLIF-Consortiumacute-on-chronic liver failure score(CLIF-C-ACLFs)models,we assessed the predictive accuracy of the nomogram using the concordance index(C-index),and its discriminative ability using time-dependent receiver operating characteristics(td-ROC)analysis,respectively.Results:Multivariate logistic regression analysis of the development set carried out to predict mortality revealed that γ-glutamyl transpeptidase,albumin,total bilirubin,urea nitrogen,creatinine,international normalized ratio,and neutrophil-to-lymphocyte ratio were independent factors,all of which were incorporated into the new nomogram to predict the mortality of HEV-ALF patients.The area under the curve of this nomogram for mortality prediction was 0.671(95%confidence interval:0.602-0.740),which was higher than that of the MELD and CLIF-C-ACLFs models.Moreover,the td-ROC and decision curves analysis showed that both discriminative ability and threshold probabilities of the nomogram were superior to those of the MELD and CLIF-C-ACLFs models.A similar trend was observed in the validation set.Conclusions:The novel nomogram is an accurate and efficient mortality prediction method for HEV-ALF patients.展开更多
High-entropy alloys are characteristic of extensive atomic occupational disorder on high-symmetric lattices,differing from traditional alloys.Here,we investigate the magnetic and thermal transport properties of the pr...High-entropy alloys are characteristic of extensive atomic occupational disorder on high-symmetric lattices,differing from traditional alloys.Here,we investigate the magnetic and thermal transport properties of the prototype face-centered-cubic high-entropy alloy CrMnFeCoNi by combining physical properties measurements and neutron scattering.Direct-current and alternating-current magnetizations measurements indicate a mictomagnetic behavior with coexisting antiferromagnetic and ferromagnetic interactions below room temperature and three anomalies are found at about 80,40,and 20 K,which are related to the paramagnetic to antiferromagnetic transition,the antiferromagnetic to ferromagnetic transition,and the spin freezing,respectively.The electrical and thermal conductivities are significantly reduced compared to Ni,and the temperature dependence of lattice thermal conductivity exhibits a glasslike plateau.Inelastic neutron scattering measurements suggest weak anharmonicity so that the thermal transport is expected to be dominated by the defect scattering.展开更多
Three-dimensional Dirac semimetal Cd_(3)As_(2)has been considered as an excellent candidate for applications of electronic devices owing to its ultrahigh mobility and air-stability.However,current researches are focus...Three-dimensional Dirac semimetal Cd_(3)As_(2)has been considered as an excellent candidate for applications of electronic devices owing to its ultrahigh mobility and air-stability.However,current researches are focused mainly on the use of gate-voltage to control its carrier transport tunability,while the manipulation of transport properties by element-doping is quite limited.Here we report the tunable magneto-transport properties by adjusting Mn-doping in the Cd_(3)As_(2)compound.We find that Mnelement doping has a strong influence on the Fermi level positions,and the Fermi energy approaches to Dirac point with higher Mn-doping.More importantly,the introduction of Mn atoms transforms diamagnetic Cd_(3)As_(2)to anti ferromagnetic(Cd,Mn)_(3)As_(2),which provides an approach to control topological protected Dirac materials by ma nipulating antiferro magnetic order parameters.The Shubnikov-de Hass oscillation originates from the surface states,and the Landau fan diagram yields a nontrivial Berry phase,indicating the existence of massless Dirac fermions in the(Cd_(1-x)Mn_x)_(3)AS_(2)compounds.Our present results may pave a way for further investigating anti ferromagnetic topological Dirac semimetal and expand the potential applications in optoelectronics and spintronics.展开更多
文摘Structural and magnetic properties of Nd15Fe70T15Nδ(T=V, Mo) alloys, made by mechanical alloying (MA) followed by heat-treatment and nitriding, have been investigated systematically.Effects of annealing temperature on the structure and magnetic properties of the materials were studied by means of X-ray diffraction, AC susceptibility and high field magnetization measurements. Under pure argon atmosphere, the optimum temperatures for the heat treatment are found to be 75 and 850℃ for Nd15Fe7015Nδ and Nd15Fe70Mo15Nδ respectively. Correspondingly, the following magnetic properties are achieved : (1) Nd15Fe70V15Nδ:Br=0.63 T,,HC=8.01kA/cm (10.1 kOe), (BH )max=50.3 kJ/m3 (6 32 MGOe), (2) Nd15Fe70Mo15Nδ :Br=0.42 T. iHc=5.6 kA/cm (7.4 kOe), (BH )max=26.6 kJ/m3 (3.34 MGOe)
基金the National Science and Technology Major Project for Infectious Diseases(2012ZX10002004).
文摘Background and Aims:Timely and effective assessment scoring systems for predicting the mortality of patients with hepatitis E virus-related acute liver failure(HEV-ALF)are urgently needed.The present study aimed to establish an effective nomogram for predicting the mortality of HEV-ALF patients.Methods:The nomogram was based on a cross-sectional set of 404 HEV-ALF patients who were identified and enrolled from a cohort of 650 patients with liver failure.To compare the performance with that of the model for end-stage liver disease(MELD)scoring and CLIF-Consortiumacute-on-chronic liver failure score(CLIF-C-ACLFs)models,we assessed the predictive accuracy of the nomogram using the concordance index(C-index),and its discriminative ability using time-dependent receiver operating characteristics(td-ROC)analysis,respectively.Results:Multivariate logistic regression analysis of the development set carried out to predict mortality revealed that γ-glutamyl transpeptidase,albumin,total bilirubin,urea nitrogen,creatinine,international normalized ratio,and neutrophil-to-lymphocyte ratio were independent factors,all of which were incorporated into the new nomogram to predict the mortality of HEV-ALF patients.The area under the curve of this nomogram for mortality prediction was 0.671(95%confidence interval:0.602-0.740),which was higher than that of the MELD and CLIF-C-ACLFs models.Moreover,the td-ROC and decision curves analysis showed that both discriminative ability and threshold probabilities of the nomogram were superior to those of the MELD and CLIF-C-ACLFs models.A similar trend was observed in the validation set.Conclusions:The novel nomogram is an accurate and efficient mortality prediction method for HEV-ALF patients.
基金financially supported by the Liaoning Revitalization Talents Program(No.XLYC1807122)the National Natural Science Foundation of China(Nos.11804346,12005243,and 51771197)+1 种基金the Key Research Program of Frontier Sciences of Chinese Academy of Sciences(No.ZDBS-LY-JSC002)the Ministry of Science and Technology of China(No.2020YFA0406002)
文摘High-entropy alloys are characteristic of extensive atomic occupational disorder on high-symmetric lattices,differing from traditional alloys.Here,we investigate the magnetic and thermal transport properties of the prototype face-centered-cubic high-entropy alloy CrMnFeCoNi by combining physical properties measurements and neutron scattering.Direct-current and alternating-current magnetizations measurements indicate a mictomagnetic behavior with coexisting antiferromagnetic and ferromagnetic interactions below room temperature and three anomalies are found at about 80,40,and 20 K,which are related to the paramagnetic to antiferromagnetic transition,the antiferromagnetic to ferromagnetic transition,and the spin freezing,respectively.The electrical and thermal conductivities are significantly reduced compared to Ni,and the temperature dependence of lattice thermal conductivity exhibits a glasslike plateau.Inelastic neutron scattering measurements suggest weak anharmonicity so that the thermal transport is expected to be dominated by the defect scattering.
基金the National Natural Science Foundation of China(No.51771197)the Chinese Academy of Sciences(No.KJZD-EW-M05)the Liaoning Revitalization Talents Program(No.XLYC1807122)。
文摘Three-dimensional Dirac semimetal Cd_(3)As_(2)has been considered as an excellent candidate for applications of electronic devices owing to its ultrahigh mobility and air-stability.However,current researches are focused mainly on the use of gate-voltage to control its carrier transport tunability,while the manipulation of transport properties by element-doping is quite limited.Here we report the tunable magneto-transport properties by adjusting Mn-doping in the Cd_(3)As_(2)compound.We find that Mnelement doping has a strong influence on the Fermi level positions,and the Fermi energy approaches to Dirac point with higher Mn-doping.More importantly,the introduction of Mn atoms transforms diamagnetic Cd_(3)As_(2)to anti ferromagnetic(Cd,Mn)_(3)As_(2),which provides an approach to control topological protected Dirac materials by ma nipulating antiferro magnetic order parameters.The Shubnikov-de Hass oscillation originates from the surface states,and the Landau fan diagram yields a nontrivial Berry phase,indicating the existence of massless Dirac fermions in the(Cd_(1-x)Mn_x)_(3)AS_(2)compounds.Our present results may pave a way for further investigating anti ferromagnetic topological Dirac semimetal and expand the potential applications in optoelectronics and spintronics.