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。
Abstract Constitutive equations are derived for the time‐dependent behavior of semicrystalline polymers at isothermal loading with small strains. A semicrystalline polymer at temperatures above the glass‐transition point for its amorphous phase is thought of as a network of macromolecules bridged by junctions (physica…
A new organic–inorganic hybrid material, that shows photoinduced reduction of refractive index as well as volume contraction, has been prepared using a sol–gel method. Whereas previous photosensitive materials show a photoinduced increase in refractive index, this hybrid material shows a significant decrease in refrac…
The interaction of a coadsorbed mixture of acetone and oxygen with a clean oxidized polycrystalline sample of TiO 2 (P25) was investigated using electron paramagnetic resonance (EPR) spectroscopy. UV illumination of the sample at low temperature (100 K) generated an unstable radical intermediate at the dehydrated (and…
Polycrystalline diamond films were synthesized on silicon substrates for the first time without diamond seeding by a very low power (38 W) microwave plasma chemical vapor deposition reaction of a mixture of helium−hydrogen−methane (48.2/48.2/3.6%). The films were characterized by time-of-flight secondary ion mass spec…
Abstract The pyrolysis product distributions of polypropylene (PP) were observed, and the experimental data were semiquantitatively analyzed by computer simulation with the Molic mouse method. Studies by many researchers on PP decomposition and experimental results achieved in this study were examined. The product dis…
Carbon nanotubes (CNTs) are composed of cylindrical graphite sheets consisting of sp(2) carbons. Due to their structure CNTs are considered to be aromatic systems. In this work the number of Kekulé structures (K) in "armchair" CNTs was estimated by using the transfer matrix technique. All Kekulé structures of the cycl…
Abstract Poly(ethylene oxide) with a molecular weight of 2,000,000 was crosslinked by a difunctional peroxide in the molten state. We determined the molecular weight between crosslinks by swelling the samples with deionized water and by indentation and dynamic mechanical analysis. Results were compared with the calcul…
La 1 - x Na x MnO 3+ δ samples with well-defined cation molecularity and oxygen contents ( x = 0.05, x = 0.13, and −0.04 ≤ δ ≤ 0.078) are analyzed with XRPD, electrical conductivity, static magnetization, and EPR measurements. The majority defects induced by oxygen over- and under-stoichiometry are cation and oxygen v…
ADVERTISEMENT RETURN TO ISSUEPREVNoteNEXTA Colloidal Templating Method To Hollow Bimetallic NanostructuresLehui Lu, Guoying Sun, Shiquan Xi, Haishui Wang, Hongjie Zhang, Tiedong Wang, and Xiaohuan ZhouView Author Information Laboratory of Physical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of…
Graphite oxide (GO)−birnessite manganese oxide (BirMO) nanocomposite was synthesized via restacking of the GO layers encapsulated with Li−BirMO layers, which precipitated in situ on the surfaces of exfoliated GO sheets. The results suggest that GO and BirMO nanosheets are stacked alternatively with their c-axis aligne…
ITO electrodes modified with a meso,meso-linked porphyrin oligomer have been prepared for the first time to achieve improved light-harvesting efficiency and a larger quantum yield for photocurrent generation as compared to the corresponding porphyrin monomer system. An increase in the number of the porphyrins in meso,…
Abstract Raman and infrared spectra were recorded for A 2 Mn 2 O 7 (A = Y, Dy, Er, Yb) pyrochlores. For the first time, lattice dynamic analysis of cubic manganate pyrochlores was carried out using a short‐range force model with four stretching and four bending force constants at the zone center. The assignment of all…
Hydrothermal technology was used to control the phase behavior and morphology of advanced electroceramics for applications as sensors, piezoelectrics, and low-loss dielectrics in microwave components. Conventional and microwave-assisted hydrothermal syntheses of perovskite-type ceramics NaNbO 3, BaZrO 3, BaHfO 3, BaMg…
Biominerals are formed through an intimate association of inorganic materials and organic macromolecules. As Douglas explains in his Perspective, materials scientists increasingly use these materials as an inspiration for new synthetic materials with superior properties. Model systems can also shed light on the mechan…
A novel route was used to prepare “perfect spherical” monodispersed carbon with a smooth surface, which has a surface area of 8 m 2 /g. Air-stable iron nanoparticles with an average size of ∼10 nm were deposited on the surface of preformed carbon spherules with the aid of power ultrasound. This coating was achieved by…
Calcium caseinate (CC) and whey protein isolate (WPI) films were prepared to contain 5 or 10% Gluconal Cal (GC), a mixture of calcium lactate and gluconate, or 0.1 or 0.2% alpha-tocopheryl acetate (VE), respectively. The pH and viscosity of film-forming solutions and the water vapor permeability and tensile property o…
Abstract Gadolinium oxide films, prepared by the sol–gel process, present waveguiding properties. Their structures were studied by waveguide Raman spectroscopy (WRS) and confirmed using transmission electron microscopy (TEM). The structural evolution of the layers with annealing temperatures from 650 up to 900°C was i…
Poly(epsilon-caprolactone) was blended with various polylactide-based polymers and processed to films by the solution casting method. Blends of 25/75, 50/50, 75/25, 90/10, and 95/5 (w/w) poly(epsilon-caprolactone)/poly(l-lactide), a 95/5 (w/w) blend of poly(epsilon-caprolactone) with a poly(d-lactide), a 50/50 (w/w) p…
The structure of T(6) human insulin has been determined at 120 K at a resolution of 1.0 A and refined to a residual of 0.183. As a result of cryofreezing, the first four residues of the B chain in one of the two crystallographically independent AB monomers in the hexameric [Zn(1/3)(AB)(2)Zn(1/3)](3) complex undergo a…
In the bacterium Escherichia coli, the AraC protein positively and negatively regulates expression of the proteins required for the uptake and catabolism of the sugar L-arabinose. This essay describes how work from my laboratory on this system spanning more than thirty years has aided our understanding of positive reg…