Materials Literature
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In order to investigate the effect of A-site substitution on phase transitions in barium titanates, dielectric permittivity in Ba 1- x (La 0.5 Na 0.5 ) x TiO 3 was measured in the temperature range up to 400 K with frequency of 100 Hz to 100 kHz by changing x from 1/8 to 4/8. The transition from classical non-relaxor…
The detailed mechanisms of the structural phase transformations that occur in epitaxial Y–hydride switchable mirrors are revealed with high resolution transmission electron microscopy (both cross sectional and plan view). The triangular ridge network that develops in Y prior to the α–β transformation is a result of {1…
The relationship between the mobility of ions and viscosity is discussed for the nematic phase of 4- n -octyl-4 ' -cyanobiphenyl (8CB). The Miesowicz viscosity coefficient η 2 exhibits a divergence at the nematic-smectic phase transition; nevertheless, normal behavior of the temperature dependence is observed for the…
Abstract Filled covulcanizates of elastomer blend comprising natural rubber (NR) and ethylene‐propylene‐diene rubber (EPDM) of commercial importance were successfully prepared by using a multifunctional rubber additive; namely, bis(diisopropyl)thiophosphoryl disulfide (DIPDIS). A Two‐stage vulcanization technique furt…
A new method of preparing transparent PbZrO 3 -PbTiO 3 -Pb(Zn 1/3 Nb 2/3 )O 3 (PZ-PT-PZN) ceramics was proposed. This is a multiprocess in which the mixtures of calcined powders were spark plasma sintered for 10 min and then thermally treated for 1 h. Although the sintering time was very short, the densities of the sa…
We report an extended x-ray absorption fine-structure investigation on the Mn K absorption edge in La 1- x Ca x MnO 3 as a function of temperature and magnetic field. The results provide microscopic evidence that the modifications in the local structure around Mn atomic sites, as a function of temperature and applied…
The discovery of the colossal magnetoresistance and pressure effects introduced new questions concerning the complex interplay among lattice structure, magnetism, and transport in doped perovskite manganites. To observe the interplay between the effect of pressure and strain due to the substrate in the La2/3Ca1/3MnO3…
It is demonstrated that a straightforward extension of the Arrhenius law accurately describes diffusion in the thermodynamically stable liquid of hard spheres. A sharp negative deviation from this behavior is observed as the liquid is compressed beyond its stability limit. This dynamical anomaly can be compared with t…
A comparative investigation has been made of the microstructure and magnetization reversal behavior of nanocomposite SmCo5/Sm2Co17 powders prepared by intensive milling and subsequent annealing. It was found that the saturation magnetization increases monotonically with the increase of the volume fraction of Sm2Co17 a…
Supramolecular tetrameric aggregates of four molecules of 7-deaza-2′-deoxyxanthosine are stabilized by unconventional C−H⋅⋅⋅O hydrogen bonds. In the solid state the tetramers stack to form a nanotube (see picture), in the center of which water molecules are found which are also stacked.
The electrochemical and chemical oxidation of extended TTF 4 and 5 are analysed by cyclic voltammetry, Visible/NIR and ESR spectroscopies, and the X-ray structures of the new salts 5 x BF(4)(CH(2)Cl(2)) and 4 x ClO(4)(THF)(1/2) are presented. The effects of structural factors on the pi-dimerization or the disproportio…
A new method for preparing aromatic polyamide-polyimide random copolymer films has been developed. Oxydianiline, pyromellitic dianhydride, and terephthaloyl chloride were evaporated separately from thermostatically controlled pulse molecular evaporation sources, which were actuated by solenoid valves, producing a poly…
Aluminum-doped zinc oxide (AZO) films were deposited on heated (300°C) glass substrates by reactive mid-frequency (mf, 50 kHz) magnetron sputtering using dual magnetron cathodes with aluminum–zinc alloy targets. In order to keep the very high deposition rate, reactive gas control using plasma emission was carried out…
Crystal engineering with nanoobjects? Spherical structurally well-defined molybdenum-oxide-based giant clusters can be appropriately functionalized to a crystalline material with the remarkable property of having discrete cluster units which get covalently linked to form chains (see picture) through Fe−O−Mo bonds afte…
The low-temperature phase behavior of two 2:1 hard-core electrolyte models has been investigated by Monte Carlo simulations. In the first model, both bivalent cations and monovalent anions are spherical, and the charges are located at the ion's centers; in the second model, bivalent cations are modeled as rigid dimers…
Catalytic ensembles suitable for alkene epoxidation with aqueous hydrogen peroxide are now accessible. They are made by grafting robust titanium silsesquioxane sites onto dimethylsiloxane polymers (see picture) followed by cross-linking to three-dimensionally netted polymers.
We have studied electromigration short-line effects in Cu damascene interconnects through experiments on lines of various lengths L, stressed at a variety of current densities j, and embedded in different dielectric materials. We observed two modes of resistance evolution: Either the resistance of the lines remains co…
Abstract Copolymers of N ‐cyclohexylmaleimide (ChMI) and methyl methacrylate (MMA) were synthesized by the emulsion semibatch copolymerization method. The effects of the monomer mixture composition on the average molecular weight ( M n and M w ), glass transition temperature (T g ), degradation temperature, mechanical…
The phenomenon of magnetization reversal in a hard magnet is studied analytically within a framework of a simplified energy minimization model for a two grain system. The transition region (a domain wall-like moment structure) is found to play a crucial role in nucleating a reversed domain and in the subsequent format…
We found a new type of dislocation motion in highly oriented pyrolytic graphite during subsurface observation by ultrasonic atomic force microscopy. As a load was applied by the tip, apparent edge-type dislocations (Frank partial dislocations) moved to the direction of climb over distances of 47 nm and returned to the…