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[en] The policrystalline SmBa2Cu2Oy was synthesized by the solid state reaction method. The dependence of AC susceptibility on temperature and applied ac field was studied. The critical temperature Tc is about 92 K. As the ac field is increased, the slope and the value of real part of susceptibility become smaller and the peak position of imaginary part TP was shifted to a lower temperature with peak broadening. Using Bean's model, we determined intergrain critical current density Jc and obtained 44 A/cm2 at 75 K. From the relation of the Jc(T)=(1-T/Tc)β we obtained )β 0.8 and found that the Josephson junction type of the SmBa2Cu2Oy is SIS junction. The peak of the imaginary part shifts to higher temperature with increasing frequency, f. from Arrhenius plot, we obtained the activation energy of about 0.96 eV.
[en] By the methods of physicochemical analysis interaction over Sb2S3-Sm cross section in ternary system Sm-Sb-S is studied its phase diagram is plotted. It is ascertained that Sb2S3-Sm cross section is a nonquasibinary cross section. On the basis of Sb2S3 solid solutions are formed, which contain up to 2 mol.%Sm at 300 K
[en] The Schulz x-ray method of planar orientations was used to characterize the statistical distribution of (0001) plane orientations for five SmCo5 magnets having energy products in the range 4.5 to 19 MGOe. X-ray intensity data were used to calculate the volume fraction of grains having their (0001) planes located in eighteen equiarea polar intervals defined by α, the tilt angle of the (0001) plane with respect to the sample plane, and phi, the azimuth angle defined from an arbitrary direction in the sample plane. From these data and assumptions about magnetization reversal, calculations of remanent magnetizations and energy products were made
[en] This new lock system of the European standard size for cylinders uses a key with up to 4 cylindrical magnets consisting of plastic bonded isotropic SmCo5. Each surface of these magnets can be magnetized independently in one of 8 distinctively different directions. Therefore, 88 = 16.106 differnet keys are possible. Corresponding to each magnetic surface in the key there are altogether 8 rotating SmCo5 magnets in the lock. These 'rotors', bearing a groove, orient themselves according to the key. Only if full correspondence is achieved the lock can be operated. The magnetic code system is combined with a mechanical code system which allows an extremely high number of variations. The advantages of this new lock system which has been developed and produced in two different forms by the lock company EVVA (EVVA Werke, Wienerbergstr. 59-65, A-1121 Vienna (Austria)) and Zeiss Ikon (Zeiss Ikon AG, Goerzallee 299, D-1000 Berlin 37, Berlin-Zehlendorf (Germany, D.R.)) are discussed in detail. (Author)
[en] X-ray absorption near edge structure (XANES) measurements above LH edge of Sm are employed to study the intermediate valence in Sm1-xGdxS(0.05 ≤ x ≤ 0.30) alloys. The split white lines at the LH edge of Sm are used to determine the average valence of SM in these alloys. The internal chemical pressure generated by substitution of smaller trivalent cation, Gd, for Sm drives the latter to a higher valence. Sm valence increases smoothly first and then undergoes an abrupt increment at a critical concentration of 16 at.% of Gd. At concentration of Gd higher than 16 at. % the increase in Sm valence is smooth and small. The data for Sm average valence for Sm1-xGdxS alloys obtained by LH absorption edges shows fair agreement with other techniques
[en] As new portable particle acceleration technologies become feasible the need for small high performance permanent magnets becomes critical. With particle accelerating cavities of a few microns, the photonic crystal fiber (PCF) candidate demands magnets of comparable size. To address this need, samarium cobalt (SmCo) nanoblades were attempted to be synthesized using the polyol process. Since it is preferable to have blades of 1-2 (micro)m in length, key parameters affecting size and morphology including method of stirring, reaction temperature, reaction time and addition of hydroxide were examined. Nanoparticles consisting of 70-200 nm spherical clusters with a 3-5 nm polyvinylpyrrolidone (PVP) coating were synthesized at 285 C and found to be ferromagnetic. Nanoblades of 25nm in length were observed at the surface of the nanoclusters and appeared to suggest agglomeration was occurring even with PVP employed. Morphology and size were characterized using a transmission electron microscope (TEM). Powder X-Ray Diffraction (XRD) analysis was conducted to determine composition but no supportive evidence for any particular SmCo phase has yet been observed.
[en] Using the methods of differential thermal, X-ray diffraction, microstructural analyses and measurement of microhardness, phase equilibria in the SmTe-Ga2Te3 system have been studied for the first time. An incongruently melting compound of the Sm2Ga2Te5 composition and a constrained solubility region based on Ga2Te3 are established to be formed in the system
[en] A method for checking the remanence induction and the maximum magnetic energy of magnets shaped as cylinders, rings or prisms, magnetized longitudinally, has been suggested. By way of a samarium-cobalt alloy magnet, the advantage of the suggested method is shown as compared to measurements on control specimens. The method is recommended for a 100% control of magnets
[en] Using the method of filtration of heterogeneous samarium amalgams, containing radioactive isotopes sup(144)Ce and sup(152)Eu, it has been shown that cerium is inserted into the solid phase of samarium amalgam, whereas europium does not cocrystallize with samarium. The solubility of praseodymium, neodymium, and gadolinium in mercury has been determined on the basis of the curves current VS time of decomposition of heterogeneous amalgams of these metals