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This article presents a method to estimate the rotational velocity of a cylindrical plasma from its two-dimensional images by an extended use of the Fourier-rectangular function transform, which was proposed to analyze the structure and dynamics of a cylindrical plasma [K. Yamasaki e t a l., J. Appl. Phys. 126 , 043304 (2019)]. The proposed method is applied to tomography images of plasmas produced in a linear cylindrical device and succeeds in obtaining the radial distribution of rotational velocity and its fluctuations, providing an interesting finding, that is, the existence of flow modulation associated with m = 1 mode fluctuations. [ABSTRACT FROM AUTHOR]

Dynamic balance model for silicon dioxide insulations is suitable for the characterization of electron trapping properties in nitrided gate insulators. Injected electron density of the nitrided insulators influences the detrapping and trapping transients, with the magnitude of trapped negative charges decreasing with increase in electric field. Occupation probability function is the same for the oxide and nitrided insulators, despite the difference in trap concentration and trapping cross sections.

Magnetization measurements for the compound SmCo(sub 3)B(sub 2) are performed on loose powder in magnetic fields to 5T and in the temperature region from 4.2 to 60 K. A magnetic first order transition occurs at T=43 K and metamagnetism occurs in the narrow temperature region between 43 and 47 K, for which some possible discussions are given.

A study was conducted to analyze the crystalline electric field at rare earth sites and the induced magnetic moment at a cobalt site in RCo3B2 compounds. The compounds were prepared using an arc furnace. High field magnetization processes were measured at different temperatures. Experimental results indicated that the crystal field parameter is very large and supports a significant magnetic moment induced at the cobalt site.

Thermal expansions of the lattice parameters a and c of the Rn+1Co(sub3n+5)B(sub2n) system were measures using an x-ray diffraction technique, to determine the nature of magnetic interactions and the chemical bond. A spontaneous magnetostriction occurs in the c plane only along the c axis. The positive spontaneous magnetostriction of the GdCo(sub4)B in the c plane is divided into three contributions. Thermal expansion coefficients in the c plane within the paramagnetic temperature region fall with rising n in the Gd system.

Experimental testing of whether Fe substitution for Sm in SmCo4B magnetic material improves the Curie temperature and saturation moment reveals that Fe substitution does not reduce magnetic anisotropy. Nitrogenation of SmCo2Fe2 enhances magnetization and Fe-Co alloy precipitation, indicating that it is a reliable method. However, nitrogenation enhances Curie temperature by 20 K and does not modify the crystal volume of the compound.

RCo3B2 compounds, with R = Gd,, Dy, Y and SM, exhibit a paramagnetic susceptibility with Pauli paramagnetic features contributed from Co sublattices of the compounds. The Gd and Dy compounds exhibit Curie-Weiss and Sm compound shows Van Vleck paramagnetism in the paramagnetic region, though all components have an antiparallel magnetic moment.

Powdered and field-oriented samples of Gd(sub 1-x)Dy(sub x)Co(sub 4)B are subjected to x-ray diffraction and magnetization measurements to determine their properties. The samples have a planar magnetic anisotropy at low temperatures, and axial magnetic anisotropy is exhibited at room temperatures and at higher temperatures. The crystallographic manufacturing process of the compound produces a permanent variation in the constituent elements of the samples.

The magnetic characteristics of Sm1-xPrxCo4-yFe7B were investigated for possible permanent magnet applications. The results showed that Pr substitution caused an increase in the saturation moment but also resulted in a decrease in the magnetic anisotropy field. In contrast, Fe substitution increased the Curie temperature and the saturation moment without any accompanying damage to the original anisotropy field.

The effect of Al substitution on the magnetic characteristics of RCo5 (R=Y, Pr, Nd and Sm) was investigated using magnetic measurements. The results showed that Al substitution caused a considerable decrease in the in the Curie temperature, the Co-sublattice moment and the magnetocrystalline anisotropy of the R sublattice. The value of the Co-sublattice moments were determined by their directions in the crystal.

The high field magnetic characteristics of GdCo4B were investigated. The results showed that the Curie temperature was 517 K while the compensation point was 421 K. The average Co-moment was 1.04 micrometers, giving an indication that the 6i-Co only has about a half of that of the 2c-site Co. In addition, the exchange parameter between Gd and Co spins was estimated to be 8.5 K from the temperature dependence of Gd-sublattice magnetization.

The characteristics of Rn+1Co3n+5B2n systems were investigated using magnetic measurements. The results showed that Sm- and Dy-atomic moments were smaller than the free ion moments in the Dy system. The magnetic anisotropy of the Dy system was planar at all temperatures below the Curie temperature. Magnetic anisotropy constants K1(Co) and K2(Co) have been determined at various temperatures for the Y system and the Sm-sublattice anisotropy constants had a maximum at n=1.

The magnetic to nonmagnetic phase transition in CrAs was investigated. The results showed that the magnetic state of the compounds around CrAs was heavily controlled by orthorhombic B-axis length. When the B-axis length was less than 3.38 angstroms, magnetic ordering did not take place and the material exhibited Pauli paramagnetic characteristics down to 0 K. A Curie-Weiss paramagnetism was observed at high temperatures for the compounds of NiAs type with larger B axis.

The electronic structures of [Ce.sub.n+1][Co.sub.3n+5][B.sub.2n] (n=0, 1, 2, and [infinity]) are calculated and the magnetic moments of Co and Ce atoms at the respective crystallographic sites are determined. The Ce[Co.sub.3][B.sub.3] compound is found to be nonmagnetic and the calculated magnetic moments in [Ce.sub.3][Co.sub.11][B.sub.4] are in good agreement with neutron diffraction data.

The strongly site-dependent Co magnetic moments are investigated by calculating electronic structure of the ferromagnetic compound La[Co.sub.4]B and La[Ni.sub.4]B. The electronic structures resulting from the calculations for the two compounds are discussed in comparison with those for La[Co.sub.3] and La[Ni.sub.5].

Samples of [Gd.sub.5-x][Dy.sub.x][Si.sub.4] (x=0, 0.5, 1, and 2 were prepared and the magnetocaloric effects together with the magnetic properties were measured in a magnetic filed up to about 2 T. It is observed that the Dy-substituted samples, which have a lower Curie temperature than that [Gd.sub.5-x][Dy.sub.x][Si.sub.4] show almost the same magnetocaloric effect as that of [Gd.sub.5-x][Dy.sub.x][Si.sub.4].

Local spin magnetic moments of Co, Ni, and La atoms and their dependences on the crystal volume in the compounds LaCo5, LaNi5, and LaCo3Ni2 are calculated. Calculated results are compared to each other and it is found that there is no significant difference between the calculation results for the compounds LaCo5, LaNi5, and LaCo3Ni2.

Magnetic properties of Ce(sub 2)[Co(sub 1-x)Ni(sub x)](sub 7)B(sub 3) compounds with x less than equal to 0.3 is studied in the temperature region from 4.2 K to 750 K. It is concluded that the compound Ce2Co7B3 is a quasi-two-dimensional antiferromagnet and becomes Pauli paramagnetic by the Ni substitution.

A discussion regarding some potential applications of the magnetic characteristics is presented on the basis of experimental data. It is revealed that homogenous distribution of Cr atoms as well as reduced presence of MnSb impurity phase in the samples is important for the first-order transition to occur in a narrow temperature region.

Electronic structures of Cen+1Co3n+5B2n compounds with n=0, 1, 2, and ∞ have been calculated and the magnetic moments of Co and Ce atoms at the respective crystallographic sites have been determined. General features of local density of states for Co atoms in Cen+1Co3n+5B2n are found to be similar to those in Yn+1Co3n+5B2n. It is found that magnetic moments of Ce atoms are not negligible and in opposite direction to the Co-sublattice magnetization in Cen+1Co3n+5B2n with n=0, 1, and 2. The CeCo3B2 compound is found to be nonmagnetic. Calculated magnetic moments in Ce3Co11B4 are in fairly good agreement with neutron diffraction data. Calculated results are also used to explain some experimental data. [ABSTRACT FROM AUTHOR]

Electronic structures of LaCo4B and LaNi4B are calculated in a self-consistent linear muffin-tin orbital method and the atomic sphere approximation. Local spin moments of Co atoms at 2c and 6i sites in LaCo4B compound have been calculated to be 1.49 and 0.61μB, respectively, which are similar to the experimental and calculated values of local Co moments in YCo4B. Calculated total magnetic moment of 3.1μB/f.u. of LaCo4B is in good agreement with 3.2μB obtained from the saturation magnetization. The Pauli paramagnetic nature of LaNi4B is also supported by the present energy band calculation. Electronic structures obtained by the present calculations for LaCo4B and LaNi4B are also discussed in comparison with those for LaCo5 and LaNi5. [ABSTRACT FROM AUTHOR]

The compound Gd5Si4 is known as a candidate for magnetic refrigerant in the vicinity of room temperature. Since Dy ion has a smaller de Gennes factor and larger angular momentum than those of Gd ion, it is expected that the Curie temperature of 335 K and magnetocaloric effect for Gd5Si4 will be decreased and increased, respectively, by Dy substitution for Gd of Gd5Si4. In this study, Gd5-xDyxSi4 with x=0, 0.5, 1, and 2 have been prepared, and the magnetocaloric effects together with the magnetic properties have been measured in a magnetic field up to about 2 T. Maximum temperature rise of 3.1 K is obtained for Gd5Si4 at the Curie temperature of 335 K and in a magnetic field of 1.92 T. The Dy-substituted samples, which have a lower Curie temperature than that of Gd5Si4, have shown almost the same magnetocaloric effect as that of Gd5Si4. The data are discussed on the basis of calculation of magnetic entropy for Gd5Si4. [ABSTRACT FROM AUTHOR]

Magnetic properties of Ce2(Co1-xNix)7B3 compounds with x⩽0.3 have been studied in the temperature region from 4.2 K to 750 K. It is proposed on the basis of experimental data that the compound Ce2Co7B3 has an antiferromagnetic order where the nearest two ferromagnetic layers separated by 12.9 Å couple very weakly antiferromagnetically. Observed metamagnetic transition in Ce2Co7B3 compound is caused by the spin flip. In the compounds Ce2(Co1-xNix)7B3, Ni atoms substitute preferentially the 2c-site Co atoms, and all atoms in the crystals except for the 2c-site Co atoms [=Co(0) atoms] seem to be nonmagnetic. The compound Ce2(Co1-xNix)7B3 becomes Pauli paramagnetic for x larger than about 0.24. [ABSTRACT FROM AUTHOR]

Local spin magnetic moments of Co, Ni, and La atoms and their dependences on the crystal volume in the compounds LaCo5, LaNi5, and LaCo3Ni2 are calculated by two methods of the self-consistent linear muffin-tin orbital sLMTOd within the atomic sphere approximation and the full potential LMTO. The generalized gradient approximation is taken into account for the calculation of the crystal volume in the nonmagnetic state. Calculated results by these methods are compared to each other. It is found that there is no significant difference between the calculation results for the compounds LaCo5, LaNi5, and LaCo3Ni2 in this work and those for the compounds YCo5, YNi5, and YCo3Ni2 reported previously by other authors. [ABSTRACT FROM AUTHOR]

Local spin magnetic moments of Co, Ni, and La atoms and their dependences on the crystal volume in the compounds LaCo5, LaNi5, and LaCo3Ni2 are calculated by two methods of the self-consistent linear muffin-tin orbital sLMTOd within the atomic sphere approximation and the full potential LMTO. The generalized gradient approximation is taken into account for the calculation of the crystal volume in the nonmagnetic state. Calculated results by these methods are compared to each other. It is found that there is no significant difference between the calculation results for the compounds LaCo5, LaNi5, and LaCo3Ni2 in this work and those for the compounds YCo5, YNi5, and YCo3Ni2 reported previously by other authors. [ABSTRACT FROM AUTHOR]

Investigates the magnetic properties of rare earth-cobalt-boron compounds. Evaluation of molecular field; Magnetization measurements; Discussion.

Deals with a study which measured magnetic properties of mixed crystals with NiAs type structure. Background on Curie temperature; Measurement of magnetic moment per manganese atom; Description of magnetic susceptibility.

Examines the magnetic properties of MnAlGe and related compounds. Procedure used in order to find the magnetic properties characteristics of the structure; Susceptibility above the Curie temperature; Measurement of the temperature dependencies of saturation magnetization and electric resistivity.

Presents a study which investigated particle size effects on magnetic properties of BaFe[sub12-2x]Ti[subx]Co[subx]O[sub19] fine particles. Brief introduction to the particles; Materials and methods used; Results and discussion.

Deals with a study which measured the temperature dependence of magnetic susceptibility of RCo[sub3]B[sub2]. Background to the study; Sample preparation and x-ray analysis; Magnetic measurements; Discussion of the results.

Presents a study which examined the role of boron in R[subn+1]cobalt[sub3n+5]boron[sub2n] systems, where R= yttrium, samarium and dysporium and n=0,1,2,3, and ∞. Curie temperature of the samples; Sample preparation and crystal structure; Magnetic measurements and results.

Presents a study which investigated magnetic properties of RTiCo[sub11] compounds with the ThMn[sub12] structure. Method used in preparing the compounds; Result of the x-ray diffraction for RTiCo[sub11]; Temperature dependence of the saturation magnetization in RTiCo[sub11] alloys; Description of the x-ray diffraction patterns of YTiCo[sub11].

Presents information on a study which measured the magnetization curves and hysteresis loops of field-oriented powders of rare-earth and related metal compounds. Analysis of the metallic compounds involved in the study; Methodology of the study; Results and discussion.

Presents a study that examined the magnetic properties of yttrium-gadolinium-cobalt-boron. Temperature range by which the compounds have been examined; Structure type of the compounds; Factor that leads to the decrease of the Curie temperature.

Presents a study that investigated the crystal structure parameter of chromium compounds. Temperature dependence of magnetic susceptibility for chromium compounds; Diagram of the crystal structure of the manganese-phosphorus type; Information on the crystallographic parameters of chromium-arsenic.

Presents a study that measured the magnetization and forced magnetostriction for manganese compounds in the paramagnetic temperature region under a high-pulse magnetic field. Sample preparations; Temperature dependence of magnetizations of the manganese compounds; Diagram of the crystal structure of hexagonal nickel-arsenic type.

Presents a study that compared the magnetic properties of several rare earth compounds. Examination of the crystal structure of the compounds; Analysis of the temperature dependence of spontaneous magnetization; Differences in the magnetocrystalline anisotropy of the rare earth-sublattice of the compounds.

Presents a study that investigated the magnetic and crystallographic properties for neodymium cobalt[sub4] boron, aluminum and gallium. Specimens and x-ray analysis; Experimental results and discussion.

Presents a study that examined the effect of aluminum substitution on the magnetic properties of rare earth cobalt[sub5]. Experimental procedures; Results and discussion.

Presents information on a study which analyzed the basic magnetic features for LaCo[sub13]-based systems in which cobalt has been replaced by iron (Fe), aluminum (Al) or Fe and Al and also systems in which lanthanum has been partially replaced by neodymium. Preparation of specimens by an induction melting under a highly pure argon atmosphere; Composition dependence of the magnetic moments of La(Co[sub1-x]Al[subx])[sub13] compounds; Illustration of the qualitative band scheme.

Presents a study which analyzed magnetocrystalline anisotropy and spin reorientation in Gd[sub1-x]Dy[subx]Co[sub4]B. Information on specimens and crystal structure; Magnetization curves for loose powder; Method used for estimating the magnetocrystalline anisotropy.

Presents a study that investigated the formation of iron[sub2]-manganese-silicon for Heusler-type L[sub2] structure with some degree of preferential disorder. Information on the sample preparations from iron and manganese; Relation between iron hyperfine field and magnetic moment of iron atom in several alloys; Calculation of iron moments in the various atomic environments.