Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
Lead zirconate titanate (PZT)-cement composites of 0-3 connectivity were produced and the effects of the frequency and electric field on the ferroelectric polarization-electric field (P-E) hysteresis of the composites were investigated. It was found that there was an increase in both the instantaneous remnant polariza…
The structural, electronic, and optical properties of Ba x Sr 1 − x TiO 3 (BST, x = 0.125, 0.250, 0.500, 0.750 and 0.875) solid solutions were investigated by first-principles calculations within generalized gradient approximation based on density-functional theory. Stable lattice structures of cubic paraelectric phas…
BaO–TeO 2 thin films were prepared from tellurium(VI) alkoxide by a sol–gel method and their structure was investigated by X‐ray diffractometry, Fourier transform infrared spectrometry, and 125 Te static nuclear magnetic resonance. Their crystallization temperature ( T c ), optical transmittance, and dielectric consta…
A photoinduced phase transition and helix untwisting in a new liquid crystal forming the SmC* phase were studied in detail. The compound consists of a cinnamoyl photosensitive fragment with C = C double bond capable of photoisomerisation and photocycloaddition. It was shown that ultraviolet (UV) irradiation (365 nm) i…
Brightly colored and more transparent optical glasses in the general chemical composition of B2O3-BaO-LiF (abbreviated as BBLi) with certain transition metal ions (each in 1 mol %) as the dopant ions have been prepared to investigate their optical absorption and photoluminescence spectra. We have measured absorption s…
A new synthesis method of Si 3 N 4 powder with a high α‐phase content, namely reductive combustion synthesis, was pioneered in the present work. Some fundamental experiments were carried out and the result indicated that the content of α‐Si 3 N 4 increases with the addition of SiO 2 and C, which considerably enhances…
Three amorphous silicon oxycarbonitrides are prepared by thermal decomposition of a polymeric precursor at different temperatures. The optical absorption spectra of these materials are measured over a wide range of excitation energies from 0.4 to 5.0 eV. The spectra are analyzed using theoretical models. Two absorptio…
The spin-Hamiltonian parameters (g factors g //, g ⊥ and hyperfine structure constants A //, A ⊥) of the approximately-tetragonal Cr5+ centers in MVO3 (M = Li, Na, K, Rb) crystals are calculated from the complete high-order perturbation formulas for d1 ions in tetragonal symmetry with the ground state . These formulas…
The impact resistance properties of T300/epoxy composite laminates are experimented at different velocities of 10—300 m/s striking on the laminates [(45/—45) 4 ] s , [(0/45/90/—45) 2 ] s , and [(0/45/90/—45) 4 ] s . The striking and residual velocities of bullets shot by a high-speed gas gun are measured by laser velo…
Multiwalled carbon nanotubes (MWCNTs) have been first coated with cobalt ferrites by a simple wet method. Transmission electron microscopy images show that ferrite nanoparticles (average diameter of 10 nm) were deposited on the sidewall of the MWCNTs. X-ray diffraction pattern exhibits representative diffraction peaks…
Electromagnetic chirality-induced negative refraction in a four-level atomic medium is investigated by initially preparing coherent states of the atom. We show that the negative refraction can be carried out with deeply depressing absorption and without simultaneously requiring both negative electric permittivity and…
The 0–3 composites with a mixture of randomly dispersed and separated ceramic particles and thermoplastic polymers provide flexible method to fabricate RF devices with adjusted mechanical and electrical properties. However, high ceramic loading levels are required to achieve high relative permittivity which, on the ot…
Polymer-stabilised blue phase (PSBP) is one of the most promising materials for display devices because of its superior electro-optical properties compared with conventional nematics. However, the application of the PSBP has a serious practical issue in that the driving voltage required is too high to drive with thin…
The synthesis, X-ray structure and variable-temperature magnetic study of new compounds of formula PPh4[Cr(dmbipy)(ox)2]·5H2O (1), AsPh4[Cr(dmbipy)(ox)2]·5H2O (2), {Ba(H2O)2[Cr(dmbipy)(ox)2]2}n·17/2nH2O (3) and {Ag(H2O)[Cr(dmbipy)(ox)2]}n·3nH2O (4) (PPh4+ = tetraphenylphosphonium cation; AsPh4+ = tetraphenylarsonium c…
Dendritic and flower-like cobalt superstructures have been selectively prepared by a facile hydrothermal route. The synthetic process involves the chemical reduction of cobalt ions and the oriented growth of cobalt nanocrystals under kinetic control independent of surfactants or external magnetic field. The dendritic…
This review focuses on novel carbosilane dendrimers containing branches with Si-C and Si-O-C bonds. Introduction of organic moieties into the dendrimers is performed by hydrosilation of carbon-carbon double/triple bonds. Versatile organic or organometallic moieties are introduced onto the peripheral regions of dendrim…
Changes in the dielectric and thermodynamical properties of electron beam-irradiated 4′-octyl-4-cyanobiphenyl (8CB) were studied. Irradiation-induced changes in the phase transition temperature, dielectric anisotropy, relaxation frequency and activation energy of an observed non-collective relaxation mode correspondin…
A simplified approach to constructing a composite material comprised of aligned electrospun nanofibers onto a flexible substrate consisting of a microfilament yarn is presented. The metal-coated knit patterns of the microfilament yarn play the role of the parallel electrode, required for the alignment of electrospun n…
Flexible polymers crystallize with chain folding, which shows a unique phenomenon called self-poisoning. As a result, minima in crystal growth rates of strictly monodisperse short-chain polymers are observed near the temperatures of transitions from extended-chain to once-folded-chain growth, from once-folded to twice…
We show that the aging of the mechanical relaxation of a gelatin gel exhibits the same scaling phenomenology as polymer and colloidal glasses. In addition, gelatin is known to exhibit logarithmic structural aging (stiffening). We find that stress accelerates this process. However, this effect is definitely irreducible…