Mn-doped ZnO diluted magnetic semiconductor nanoparticles are prepared by an ultrasonic assisted sol-gel process.Transmission electron microscopy shows pseudo-hexagonal nanoparticles with an average size of about 24 n...Mn-doped ZnO diluted magnetic semiconductor nanoparticles are prepared by an ultrasonic assisted sol-gel process.Transmission electron microscopy shows pseudo-hexagonal nanoparticles with an average size of about 24 nm.From the analysis of X-ray diffraction,the Mn-doped ZnO nanoparticles are identified to be a wurtzite structure without any impurity phases.The magnetic properties are measured by using superconducting quantum interference device.For the ZnO with 2% Mn doping concentration,a good hysteresis loop indicates fine ferromagnetism with a Curie temperature higher than 350 K.展开更多
The electronic structure and the magnetic properties of the molecule-based ferromagnets Cu[C(CN)3]2 and Mn[C(CN)3]2 are studied according to first principles within density-functional theory (DFT) and the full p...The electronic structure and the magnetic properties of the molecule-based ferromagnets Cu[C(CN)3]2 and Mn[C(CN)3]2 are studied according to first principles within density-functional theory (DFT) and the full potential linearized augmented plane wave (FP-LAPW) method. The total energy, atomic spin magnetic moments, and density of states (DOS) of Cu[C(CN)3]2 and Mn[C(CN)3]2 are all calculated. The calculations reveal that the compounds have a stable ferromagnetic ground state and half-metallic properties. The total spin magnetic moment is 1.0μB for Cu[C(CN)3]2 and 5.0#B for Mn[C(CN)3]e per molecule, the magnetic moment mainly comes from metal atoms, although there is a slight contribution from N and C atoms.展开更多
To prepare and characterize the ferromagnetic fluid of Fe304 modified by carboxyl PEG (FF/carboxyl PEG) for hyperthermia of tumor, the magnetic nanoparticles (NPs) of Fe304 were prepared by chemical co-precipitati...To prepare and characterize the ferromagnetic fluid of Fe304 modified by carboxyl PEG (FF/carboxyl PEG) for hyperthermia of tumor, the magnetic nanoparticles (NPs) of Fe304 were prepared by chemical co-precipitation method, and then modified with carboxyl PEG. The iron content of FFs was determined by spectrophotometric method using o-phenanthroline. The stability of FF/carboxyl PEG was assessed by the sedimentation method. FF/carboxyl PEG was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), infrared spectrometry (IR) and vibrating sample magnetometer (VSM). Heating effect of FF/carboxyl PEG was measured in an alternating magnetic field in vitro. The stability of FF/carboxyl PEG was much better than that of unmodified ferromagnetic fluid. FF/carboxyl PEG was proved to be composed of Fe304 by both XRD and IR. TEM showed that the ferromagnetic particles were well-dispersed. The average particle size was calculated as 5 nm by XRD. The saturation magnetization and residual magnetization of FF/carboxyl PEG were 47.01 and 3.41 emu/g, respectively. The coercive force was 6.70e. The specific absorption rate (SAR) of the FF/carboxyl PEG was 63.0 W/g[Fe]. The FF/carboxyl PEG shows the promise for hyperthermia of tumor.展开更多
基金Supported bythe Hunan Provincial Natural Science Foundation ofChina (No.05JJ30126) the Scientific Research Fund of HunanProvincial Education Department (No.04B061)+1 种基金the Key Labora-tory of Advanced Materials & Rheological Properties (Xiangtan University) ,Ministry of Education (No.KF0506) ,the Fundof Xiangtan University (05IND10) .
文摘Mn-doped ZnO diluted magnetic semiconductor nanoparticles are prepared by an ultrasonic assisted sol-gel process.Transmission electron microscopy shows pseudo-hexagonal nanoparticles with an average size of about 24 nm.From the analysis of X-ray diffraction,the Mn-doped ZnO nanoparticles are identified to be a wurtzite structure without any impurity phases.The magnetic properties are measured by using superconducting quantum interference device.For the ZnO with 2% Mn doping concentration,a good hysteresis loop indicates fine ferromagnetism with a Curie temperature higher than 350 K.
基金Supported by the National Natural Science Foundation of China under Grant No.10974048the Excellent Middle Age and Youth People Science and Technology Creative Team Foundation of the Educational Department of the Hubei Province under Grant No.T200805
文摘The electronic structure and the magnetic properties of the molecule-based ferromagnets Cu[C(CN)3]2 and Mn[C(CN)3]2 are studied according to first principles within density-functional theory (DFT) and the full potential linearized augmented plane wave (FP-LAPW) method. The total energy, atomic spin magnetic moments, and density of states (DOS) of Cu[C(CN)3]2 and Mn[C(CN)3]2 are all calculated. The calculations reveal that the compounds have a stable ferromagnetic ground state and half-metallic properties. The total spin magnetic moment is 1.0μB for Cu[C(CN)3]2 and 5.0#B for Mn[C(CN)3]e per molecule, the magnetic moment mainly comes from metal atoms, although there is a slight contribution from N and C atoms.
文摘To prepare and characterize the ferromagnetic fluid of Fe304 modified by carboxyl PEG (FF/carboxyl PEG) for hyperthermia of tumor, the magnetic nanoparticles (NPs) of Fe304 were prepared by chemical co-precipitation method, and then modified with carboxyl PEG. The iron content of FFs was determined by spectrophotometric method using o-phenanthroline. The stability of FF/carboxyl PEG was assessed by the sedimentation method. FF/carboxyl PEG was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), infrared spectrometry (IR) and vibrating sample magnetometer (VSM). Heating effect of FF/carboxyl PEG was measured in an alternating magnetic field in vitro. The stability of FF/carboxyl PEG was much better than that of unmodified ferromagnetic fluid. FF/carboxyl PEG was proved to be composed of Fe304 by both XRD and IR. TEM showed that the ferromagnetic particles were well-dispersed. The average particle size was calculated as 5 nm by XRD. The saturation magnetization and residual magnetization of FF/carboxyl PEG were 47.01 and 3.41 emu/g, respectively. The coercive force was 6.70e. The specific absorption rate (SAR) of the FF/carboxyl PEG was 63.0 W/g[Fe]. The FF/carboxyl PEG shows the promise for hyperthermia of tumor.