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。
The Potts Monte Carlo simulation was used to simulate microstructural evolution in uranium dioxide fuel rods. During service, grain growth, pore migration, and thermal segregation of the pores and UO 2 occur in the rods in a thermal gradient. In this investigation, we developed a model which simulates simultaneous gra…
A composite oxide containing samaria‐doped ceria [SDC, ( CeO 2 ) 0.8 ( SmO 1.5 ) 0.2 ] and yttria‐stabilized zirconia [YSZ, ( ZrO 2 ) 0.92 ( Y 2 O 3 ) 0.08 ] was developed as an electrolyte for a solid oxide fuel cell (SOFC). A SOFC with a YSZ electrolyte was characterized by a high open‐circuit voltage (OCV) and a st…
Plasticized polyvinyl chloride (PVC), although not a blood-compatible polymer, is the material of choice for the manufacture of blood bags and hemodialysis tubing throughout the world. PVC is usually plasticized with di-(2-ethylhexyl phthalate) (DEHP) to impart flexibility and low temperature properties to the final p…
We have measured the (cubic-lattice-approximation) elastic moduli of optical melt-zone-grown single-crystal ${\mathrm{La}}_{0.83}{\mathrm{Sr}}_{0.17}{\mathrm{MnO}}_{3}$ using resonant ultrasound spectroscopy. We observe the structural transition at 285 K to be hysteretic in the ambient (almost zero) magnetic field. A…
We present results of high-pressure single-crystal x-ray-diffraction studies and ab initio pseudopotential calculations of stoichiometric ${\mathrm{TiS}}_{2}$. Neither present any evidence for a structural phase transition; it is shown that the material undergoes an isostructural semiconductor-semimetal phase transiti…
Prolonged photoirradiation induces a volume expansion and causes a decrease in the optical bandgap (photodarkening) in well annealed amorphous chalcogenides. A microscopic mechanism for the origin of these changes is proposed in terms of the repulsive Coulomb force between layered clusters which can be negatively char…
The classical spherical cap geometry which is used to define the shape of sessile drops resting on polymer surfaces has a deficiency, since it is a two-parameter model of the three measurable drop dimensions: contact angle, base radius, and height. In this paper, mathematical expressions for a drop having all three me…
We show that when a typically antiferroelectric material such as ${\mathrm{PbZrO}}_{3}$ or ${\mathrm{BiNbO}}_{4}$ is deposited as a thin film on a semiconducting substrate (Si), it displays ferroelectric behavior below a critical film thickness characteristic of the system. In an attempt to understand this ``size effe…
The bifunctional P-protein, which plays a central role in Escherichia coli phenylalanine biosynthesis, contains two catalytic domains (chorismate mutase and prephenate dehydratase activities) as well as one R-domain (for feedback inhibition by phenylalanine). Six genes coding for P-protein domains or subdomains were c…
Detailed measurements of the acoustic emissions from single-bubble sonoluminescence have been made utilizing both a small 200-μm aperture PVDF needle hydrophone, and a focused 10-MHz transducer. Signals obtained with the needle hydrophone show a fast (5.2 ns), probably bandlimited rise time and relatively large pulse…
The effect of curing temperature on the electro-optic behaviour and network morphology of reverse mode polymer stabilized cholesteric textures (PSCTs) has been studied. Scanning electron micrographs indicate that increasing the curing temperature generally results in a larger average void size within a polymer network…
An inexpensive electrochemical capacitor system with an asymmetric configuration is demonstrated. The system includes heteropolyacids and a proton‐exchange polymer membrane. Heteropolyacid electrodes show facile redox processes and host large amounts of easily accessible mobile protons required for charge balance. The…
Recent studies of potential components for nanomachines reveal that for a wide variety of structures, the rigidity of the structure is a key element in its proper performance. Vibrational analysis is an ideal way to study structural rigidity, but standard methods of molecular vibrational analysis are computationally p…
This study demonstrates the shielding effects of a silica-ash layer on the combustion of silicones and their possible applications on the fire retardancy of organic materials. The deposited silica-ash layer, formed on the surface of silicone materials during combustion, has shielding effects on the combustion of silic…
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTSwitching on the Nucleophilic Reactivity of a Ferric Porphyrin Peroxo ComplexMatthias Selke and Joan Selverstone ValentineView Author Information Department of Chemistry and Biochemistry University of California, Los Angeles Los Angeles, California 90095-1589 Cite this…
ABSTRACT Water sorption, water vapor permeability, and tensile properties were evaluated for zein films plasticized with oleic acid. The effect of relative humidity on water vapor permeability and tensile properties of films was investigated. Samples were produced by two different methods: casting from a zein solution…
The electrochemical behavior of thin sputter‐deposited mixed oxide films with ‐contents of 10, 20, 50, and 90% was studied with in situ X‐ray absorption near edge spectroscopy (XANES). These measurements gave information on the chemical states and dissolution rates during anodic and cathodic polarization in different…
ABSTRACT Transglutaminase (TG) was used to produce films from whey protein isolate, soybean 11S globulin and a mixture of the two (1:1, wt/wt). Solubility of TG cross‐linked films was lower than that of control films at pH 3, 4, 6 and 8. Solubility of control films in 6.6M urea and in 10% SDS was higher than that of T…
The coherency defect technique is developed for the domain pattern energetics in rhombohedral (001) epitaxial ferroelectric films. The coherency defects that are necessary to maintain the epitaxy during the ferroelectric phase transition are considered to be the only sources of elastic strains and stresses (and, corre…
The first nucleobase-functionalized polythiophenes, e.g., the uracil-substituted polythiophene shown in the Figure, produced by electrochemical oxidation of bithiophenes covalently linked to the nucleobases uracil and adenine, are reported. Their synthesis, characterization, and polymerization are detailed and the inf…