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In this paper, the relationship between the initial crystalline behavior and annealing conditions in pulsed laser deposition (PLD)-made Nd-Fe-B and Pr-Fe-B films with rare-earth-rich composition is discussed. The films with rare-earth-rich compositions are prepared via PLD. An annealing process is necessary to obtain the crystalline 2-14-1 phase of hard magnetic properties because all the as-deposited films have an amorphous structure. In conventional annealing, the initial crystallization of the Pr2Fe14B phase occurred at lower temperatures compared with that of the Nd2Fe14B phase, indicating that the annealing temperature of the initial crystallization of the Pr2Fe14B phase was lower than that of the Nd2Fe14B phase. Considering the same crystallization temperature in both the phases, the melting points of both rare-earth elements, Nd and Pr, are considered to relate to the initial crystallization behavior. We also confirmed that the annealing time for Pr2Fe14B phase formation was shorter than that for Nd2Fe14B phase formation., AIP Advances, 13(2), art. no. 025006; 2023

In this paper, the relationship between the initial crystalline behavior and annealing conditions in pulsed laser deposition (PLD)-made Nd-Fe-B and Pr-Fe-B films with rare-earth-rich composition is discussed. The films with rare-earth-rich compositions are prepared via PLD. An annealing process is necessary to obtain the crystalline 2-14-1 phase of hard magnetic properties because all the as-deposited films have an amorphous structure. In conventional annealing, the initial crystallization of the Pr2Fe14B phase occurred at lower temperatures compared with that of the Nd2Fe14B phase, indicating that the annealing temperature of the initial crystallization of the Pr2Fe14B phase was lower than that of the Nd2Fe14B phase. Considering the same crystallization temperature in both the phases, the melting points of both rare-earth elements, Nd and Pr, are considered to relate to the initial crystallization behavior. We also confirmed that the annealing time for Pr2Fe14B phase formation was shorter than that for Nd2Fe14B phase formation., AIP Advances, 13(2), art. no. 025006; 2023

type:Journal Article, We have investigated reflection properties of light-matter strong coupling in a planar metal-mirror microcavity with highly concentrated PIC J-aggregates. Large vacuum Rabi-splitting ranging from 100 to 250 meV is obtained depending on the concentration of the J-aggregates. The factors for providing these large Rabi-splitting will be discussed based on its concentration dependence. We also present our recent study focused on microscopic reflection properties of the microcavity. We have improved microscope optics which enables us to measure local reflection spectra within 0.3-m-diameter area. Observation of incident-light-angle dependence becomes possible. We found existence of micrometer-scale inhomogeneity in the Rabi-splitting (e.g. ±10% in a region), which will be interpreted mainly by the spatial distribution of J’s in the active layer., source:https://doi.org/10.1016/j.phpro.2010.01.229

Internal mixers are widely used in rubber compounding for tires. It is not sufficiently examined the distributive mixing in the mixer and a relation between a flow in the chamber and the compounding qualities. Therefore, it is important to establish flow analysis technique for developing better performance mixers and rotors. In this study, three-dimensional numerical study has been carried out to investigate the mixing flow in the mixers. It is assumed that mixer was partially or fully filled with isothermal rubber in the simulation. Tangential two-wing rotors were selected as a mixing rotor. Fill factor was changed from 60 to 100 %. Particle tracking method was applied, and minimum distance between each particle was used for the evaluation of distributive mixing. From the results, it was suggested that the minimum distance between each particle could evaluate distributive mixing stability, and that fill factor has significant effect on the distributive mixing., Internal mixers are widely used in rubber compounding for tires. It is not sufficiently examined the distributive mixing in the mixer and a relation between a flow in the chamber and the compounding qualities. Therefore, it is important to establish flow analysis technique for developing better performance mixers and rotors. In this study, three-dimensional numerical study has been carried out to investigate the mixing flow in the mixers. It is assumed that mixer was partially or fully filled with isothermal rubber in the simulation. Tangential two-wing rotors were selected as a mixing rotor. Fill factor was changed from 60 to 100 %. Particle tracking method was applied, and minimum distance between each particle was used for the evaluation of distributive mixing. From the results, it was suggested that the minimum distance between each particle could evaluate distributive mixing stability, and that fill factor has significant effect on the distributive mixing.

ERS 2011 Amsterdam ERJ, info:eu-repo/semantics/published

info:eu-repo/semantics/published

info:eu-repo/semantics/published

ERS 2011 Amsterdam ERJ, info:eu-repo/semantics/published

The deformation mechanisms which operate during superplastic tensile deformation at 783 K in a AlCu4Mg/Si3N4/20p composite have been investigated by means of the crystallographic texture evolution with strain. Three stages of texture evolution have been observed: in stage I, little texture variation occurs up to a true strain of 0.4. In stage II, a progressive decrease of texture intensity up to a true strain of 0.8 is noted. This suggests that a mechanism of grain boundary sliding, GBS, typical of superplastic deformation of monolithic fine grained polycrystalline materials, prevails in this stage. At higher deformations, in stage III, the intensity of the main texture components tends to increase, indicating that the dominant deformation mechanism becomes crystallographic slip, CS.

We investigate composite Fe–SrF2 films to explore new materials showing the granular-type tunnelling magnetoresistance (TMR) effect. The films are composed of Fe nano-particles embedded in a SrF2 matrix. The electromagnetic properties of the ferromagnetic metal–insulator films are confirmed, including super-paramagnetism, tunnel conduction and TMR. We obtain a TMR of 3% at RT and 5% at 77 K. The film resistivity is much higher than that of oxide-based granular film. We also fabricate the nanostructures of granular films and aim at the application of the single-electron transistor. As a result, we observed a Coulomb blockade (CB) region and CB oscillation at low temperature.

We investigate composite Fe–SrF2 films to explore new materials showing the granular-type tunnelling magnetoresistance (TMR) effect. The films are composed of Fe nano-particles embedded in a SrF2 matrix. The electromagnetic properties of the ferromagnetic metal–insulator films are confirmed, including super-paramagnetism, tunnel conduction and TMR. We obtain a TMR of 3% at RT and 5% at 77 K. The film resistivity is much higher than that of oxide-based granular film. We also fabricate the nanostructures of granular films and aim at the application of the single-electron transistor. As a result, we observed a Coulomb blockade (CB) region and CB oscillation at low temperature.

We investigate composite Fe–SrF2 films to explore new materials showing the granular-type tunnelling magnetoresistance (TMR) effect. The films are composed of Fe nano-particles embedded in a SrF2 matrix. The electromagnetic properties of the ferromagnetic metal–insulator films are confirmed, including super-paramagnetism, tunnel conduction and TMR. We obtain a TMR of 3% at RT and 5% at 77 K. The film resistivity is much higher than that of oxide-based granular film. We also fabricate the nanostructures of granular films and aim at the application of the single-electron transistor. As a result, we observed a Coulomb blockade (CB) region and CB oscillation at low temperature.

We investigate composite Fe–SrF2 films to explore new materials showing the granular-type tunnelling magnetoresistance (TMR) effect. The films are composed of Fe nano-particles embedded in a SrF2 matrix. The electromagnetic properties of the ferromagnetic metal–insulator films are confirmed, including super-paramagnetism, tunnel conduction and TMR. We obtain a TMR of 3% at RT and 5% at 77 K. The film resistivity is much higher than that of oxide-based granular film. We also fabricate the nanostructures of granular films and aim at the application of the single-electron transistor. As a result, we observed a Coulomb blockade (CB) region and CB oscillation at low temperature.

The codeposition of Co with Zn from highly acidified electrowinning baths showed normal codeposition at low current density, and anomalous codeposition at higher current density. The same trend was found with Zn-Co alloy weakly acidified electroplating baths. The current density at which the transition from normal to anomalous occurred increased with increasing concentrations of Co and sulphuric acid. Comparison of the polarisation curve and deposition behaviours of Co and Zn for the two methods revealed that the critical current density, above which the consistent Zn deposition occurs in Zn electrowinning, was identified with the transition current desnity in alloy plating., The codeposition of Co with Zn from highly acidified electrowinning baths showed normal codeposition at low current density, and anomalous codeposition at higher current density. The same trend was found with Zn-Co alloy weakly acidified electroplating baths. The current density at which the transition from normal to anomalous occurred increased with increasing concentrations of Co and sulphuric acid. Comparison of the polarisation curve and deposition behaviours of Co and Zn for the two methods revealed that the critical current density, above which the consistent Zn deposition occurs in Zn electrowinning, was identified with the transition current desnity in alloy plating.

The behaviour of impurity Co present in Zn electrowinning bath was studied. It was shown that the normal type codeposition (where the electrochemically noble Co deposited preferentially) occurred in the low current density region, while the preferential deposition of electrochemically less noble Zn (anomalous codeposition) occurred at higher current densities. The cathode current efficiency was extremely poor in the normal type codeposition while it increased remarkably in the anomalous type codeposition. The transition current density at which the abrupt transition from a normal to an anomalous type occurred was increased in magnitude with increasing the Co and sulphuric acid concentrations in the bath. In addition, the comparisons of polarisation curve and codeposition behaviour for both metals for Zn-Co alloy deposition with those for Zn electrowinning from the Co-containing bath revealed that the transition current density in alloy deposition was identical with the critical current density in electrowinning., The behaviour of impurity Co present in Zn electrowinning bath was studied. It was shown that the normal type codeposition (where the electrochemically noble Co deposited preferentially) occurred in the low current density region, while the preferential deposition of electrochemically less noble Zn (anomalous codeposition) occurred at higher current densities. The cathode current efficiency was extremely poor in the normal type codeposition while it increased remarkably in the anomalous type codeposition. The transition current density at which the abrupt transition from a normal to an anomalous type occurred was increased in magnitude with increasing the Co and sulphuric acid concentrations in the bath. In addition, the comparisons of polarisation curve and codeposition behaviour for both metals for Zn-Co alloy deposition with those for Zn electrowinning from the Co-containing bath revealed that the transition current density in alloy deposition was identical with the critical current density in electrowinning.

The characteristics of iron-group metals, compared with other impurities, were revealed in the impurity content of the deposits as well as its deposition rate. The SEM images of the deposits obtained from belts containing iron-group metals were similar to those of pure zinc, while Au, Cu, and Cd affected the morphology of the deposits significantly. The presence of iron-group metals in the solutions further resulted in the distinct pattern of the potential oscillation caused by the deposition and dissolution of cathode zinc. Thus it may be necessary to distinguish the iron-group metals from other impurities in the discussion of impurity effects in zinc electrowinning., The characteristics of iron-group metals, compared with other impurities, were revealed in the impurity content of the deposits as well as its deposition rate. The SEM images of the deposits obtained from belts containing iron-group metals were similar to those of pure zinc, while Au, Cu, and Cd affected the morphology of the deposits significantly. The presence of iron-group metals in the solutions further resulted in the distinct pattern of the potential oscillation caused by the deposition and dissolution of cathode zinc. Thus it may be necessary to distinguish the iron-group metals from other impurities in the discussion of impurity effects in zinc electrowinning.