Materials Literature
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Ce substitution for the Ba site shifted the Curie point to a lower temperature than typical substitution with elements such as Zr and Sr. The substitution of Ce for the Ba sites up to 2.0 mol% exhibited a typical donor-doped behavior, the material being fine grained and of depressed dielectric constant at the Curie po…
Abstract The results of comparison of experimental 35 C1 NQR parameters for a great number of organic and organometallic compounds and estimated ones using ab initio calculations at the RHF/6-31G(d) level were systematized. The NQR frequency changes on going from one compound to another depend, in general, on the chan…
A bimetallic, fully alloyed Pd/Au colloid of 3.0 nm particle size, obtained by the co-reduction of Pd and Au salts with tetraalkylammonium triethylhydroborate, was embedded in a silica matrix employing a modified sol–gel procedure with THF as the solvent. The removal of the protecting tenside led to a mesoporous textu…
For freedom from zigzag defects in SSFLCD, it is important to research in detail the effect of surface smoothness of substrate on the chevron layer structure. We have studied the effect of surface roughness of undercoating layer on the surface smoothness of alignment film and then the alignment structure of SSFLC. Fur…
Single-crystal bismuth thin films, fabricated by electrodeposition and suitable annealing, exhibit very large magnetoresistance of 400 000% at 5 K and 300% at 300 K, as well as pronounced Shubnikov–de Haas oscillations. A hybrid structure demonstrates the potential for field sensing with sensitivities of 35%/Oe at 5 K…
Structure, magnetic, and transport properties of the compounds La2/3Ca1/3Mn1−xTixO3(0⩽x⩽0.3) have been investigated. The substitution of a Ti4+ ion for a Mn4+ ion suppresses the ferromagnetism and metallic conduction significantly. In the case of low doping (x⩽0.04), Curie temperature TC decreases linearly with the su…
Copper (II) oxide thin films doped with Li and Al were prepared by a liquid phase method on glass substrate. The used reagents were mainly Cu(OAc){sub 2}, Al({sup i}OPr){sub 3} and LiOAc. The films were crystallized as black CuO crystal by heating above 300 C. The electrical conductivity of the doped films changed as…
The properties of existing superconductors with ejectron spectrum instabilities, namely charge-density waves (CDWs) and spin-density waves (SDWs), are reviewed. In such substances the superconducting gap exists over the whole Fermi surface, whereas the dielectric gap emerges only on its nested sections. In particular,…
Thick, hard-magnetic Nd–Fe–B films (∼1 mm) were deposited on different substrates (Cu, steel) by a low-pressure plasma-spraying process. The properties of the applied Nd–Fe–B powders (e.g., grain size, composition) and the conditions of the spraying process were optimized with respect to the mechanical and magnetic pr…
The temperature dependence of magnetic hysteresis of RCox:Co (R=Pr and Sm) nanocomposite films is reported. These films are prepared by dc and rf sputtering and subsequent thermal processing. It is found that the squareness of the hysteresis loops deteriorates with decreasing temperature. This is attributed to the enh…
Ultrafine Ni0.65Zn0.35Cu0.2Fe1.8O4 particles were fabricated by a sol–gel method. The magnetic and structural properties of the powders were investigated with x-ray diffraction, vibrating sample magnetometer, and Mössbauer spectroscopy. Ni–Zn–Cu ferrite powders that were fired at and above 823 K have only a single pha…
The first detailed investigation of the crystalline R-phases in the Mg−Zn−Al ternary system is reported, which will assist with the interpretation and understanding of similar quasicrystalline phases in this phase diagram. Although “Mg 32 (Zn,Al) 49 ” was originally reported by Bergman and Pauling in 1956, some detail…
Bath mixtures of ethanol and ethylene glycol in dry ice produce sustainable constant temperatures over the range from -12 to -78 °C, which show a linear relationship between the bath temperature and the volume fraction of ethylene glycol. Our bath is less toxic than previously reported mixtures of ortho - and meta -xy…
A real-time in situ study of the initial stages of the interaction of oxygen with Ni(111) in a high temperature scanning tunneling microscope (STM) at temperatures between 400 and 470 K is presented. Oxygen adsorption features, in particular the Ni(111)-p(2×2)O reconstruction, were identified in room temperature STM i…
The radioluminescence and thermoluminescence spectra of synthetic zircon crystals doped with individual trivalent rare earth element (REE) ions (Pr, Sm, Eu, Gd, Dy, Ho Er, and Yb) and P are reported in the temperature range 25 to 673 K. Although there is some intrinsic UV/blue emission from the host lattice, the domin…
The dependence of the pressure threshold of martensitic transformations on the disordering degree of starting structures is considered for graphite-like BN into diamond-like BN modifications transitions. The effect of loading conditions on transformation mechanisms of rhombohedral BN into zinc blende or wurtzite modif…
A constant deflection device designed for use within a transmission electron microscope (TEM) was used to study the change in dislocation configuration ahead of a crack tip during stress corrosion cracking (SCC) of brass in water, Ti-24% Al-11% Nb alloy in methanol (CH3OH), and the initiation of SCC. In-situ tensile t…
Metal-bonded cobalt ferrite composites are promising candidates for torque sensors and other magnetostrictive sensing and actuating applications. In the present study, the temperature dependence of the magnetomechanical effect in a ring-shape cobalt ferrite composite under torsional strain has been investigated in the…
It is demonstrated through the comparison of analytical, numerical, and experimental results that the existence of excess eddy current losses can be explained by the peculiar nature of the nonlinear diffusion of electromagnetic fields in magnetically nonlinear laminations. The essence of this peculiar nature is that n…
A bis(ether amine) containing the ortho-substituted phenylene unit and pendant tert-butyl group, 1,2-bis(4-aminophenoxy)-4-tert-butylbenzene, was synthesized and used as a monomer to prepare polyimides with six commercial dianhydrides via a conventional two-stage procedure. The intermediate poly(amic acid)s had inhere…