Materials Literature
文献浏览
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。
Titelei
Electrochromic Behavior of Nickel Oxide Electrodes: II . Identification of the Bleached State by Raman Spectroscopy and Nuclear Reactions
Three different types of nickel oxide electrochromic films are colored and bleached in 1 M KOH solution: porous NiO prepared by anodic oxidation of nickel, NiO ( OH ) x obtained by reactive evaporation, and Ni ( OH ) 2 cathodically deposited. Their crystallographic and chemical identification in the colored and bleach…
Is There a Growing Correlation Length near the Glass Transition?
We present the results of a molecular-dynamics study on a Lennard-Jones mixture. Measurements of density and bond-angle correlation functions show that the answer to the question posed in the title is NO. We also show that icosahedral order plays no special role in the glass transition, but that a normalized measure o…
Octahedral occupancy and the chemical composition of diagenetic (low-temperature) chlorites
Abstract The chemical composition of about 500 diagenetic chlorites, determined by electron microprobe, has been studied in six different sedimentary sequences spanning conditions from early diagenesis to low-grade metamorphism, in the temperature range 40–330°C. The range of Fe/(Fe + Mg) is almost complete and is pos…
1991 Whitney Award Lecture: Inhibitors—An Old Remedy for a New Challenge
This lecture initially presents the results of systematic research performed to interpret the mechanisms of corrosion inhibitors in various environments. The behavior of several series of S-containing and N-containing compounds has been investigated by radiochemical, electrochemical, gravimetric, and micrographical te…
The energetics and structure of nickel clusters: Size dependence
The energetics of nickel clusters over a broad size range are explored within the context of the many-body potentials obtained via the embedded atom method. Unconstrained local minimum energy configurations are found for single crystal clusters consisting of various truncations of the cube or octahedron, with and with…
The glass transition of organic liquids confined to small pores
The glass-transition temperatures, Tg, of organic liquids confined to small pores were studied by differential scanning calorimetry (DSC). The Tg was measured as a function of pore size in controlled pore glasses (CPG) having pore diameters in the range of 40–730 Å. The surface of the glass was treated with hexamethyl…
One-step synthesis of hyperbranched dendritic polyesters
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTOne-step synthesis of hyperbranched dendritic polyestersC. J. Hawker, R. Lee, and J. M. J. FrechetCite this: J. Am. Chem. Soc. 1991, 113, 12, 4583–4588Publication Date (Print):June 1, 1991Publication History Published online1 May 2002Published inissue 1 June 1991https://pubs…
Hydrophobic effects on simple organic reactions in water
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTHydrophobic effects on simple organic reactions in waterRonald BreslowCite this: Acc. Chem. Res. 1991, 24, 6, 159–164Publication Date (Print):June 1, 1991Publication History Published online1 May 2002Published inissue 1 June 1991https://pubs.acs.org/doi/10.1021/ar00006a001ht…
Transition from “Supercapacitor” to “Battery” Behavior in Electrochemical Energy Storage
The storage of electrochemical energy in battery, "supercapacitor," and double‐layer capacitor devices is considered. A comparison of the mechanisms and performance of such systems enables their essential features to be recognized and distinguished, and the conditions for transition between supercapacitor and "battery…
A structural and mechanistic comparison of pyridoxal 5'-phosphate dependent decarboxylase and transminase enzymes
Stereochemical studies of three pyridoxal phosphate dependent decarboxylases and serine hydroxymethyltransferase have allowed the dispositions of conjugate acids that operate at the C alpha and C-4' positions of intermediate quinoids to be determined. Kinetic work with the decarboxylase group has determined that two d…
Design and synthesis of new enzymes based on the lactate dehydrogenase framework
Analysis of the mechanism and structure of lactate dehydrogenases is summarized in a map of the catalytic pathway. Chemical probes, single tryptophan residues inserted at specific sites and a crystal structure reveal slow movements of the protein framework that discriminate between closely related small substrates. On…
.gamma.-Chymotrypsin is a complex of .alpha.-chymotrypsin with its own autolysis products
The determination of three separate gamma-chymotrypsin structures at different temperatures and resolutions confirmed the presence of electron density in the active site, which could be interpreted as an oligopeptide as had previously been suggested by Dixon and Matthews [(1989) Biochemistry 28, 7033-7038]. HPLC analy…
Low-temperature phase transitions and twin-domain structure of (NH4)3H(SeO4)2studied by the electron paramagnetic resonance of Cu2+, VO2+and SeO3-
Low-temperature phase transitions and twin-domain structure of (NH4)3H(SeO4)2 studied by the electron paramagnetic resonance of Cu2+, VO2+ and SeO3-, Wu Ching-Jiun, Yu Jiang-Tsu, Tsai Mei-Na, Lou Ssu-Hao
Raman analysis of Si/Ge strained-layer superlattices under hydrostatic pressure
Raman scattering was used to study optical phonons in a Si12Ge4 strained-layer superlattice on c-Si(001) that was subjected to hydrostatic pressure at room temperature. The change of phonon frequency with pressure, dω/dP, for the principal quasi-confined LO mode in the Ge layers, is found to be significantly smaller t…
Anisotropic thermal conductivity of the 2D single quasicrystals:Al65Ni20Co15andAl62Si3Cu20Co15
The anisotropic thermal conductivity of ${\mathrm{Al}}_{65}$${\mathrm{Ni}}_{20}$${\mathrm{Co}}_{15}$ and ${\mathrm{Al}}_{62}$${\mathrm{Si}}_{3}$${\mathrm{Cu}}_{20}$${\mathrm{Co}}_{15}$ single quasicrystals has been measured. While a nearly isotropic phonon contribution was observed, the electronic thermal conductivity…
Disorder and the optical spectroscopy of Cr3+-doped glasses. II. Glasses with high and low ligand fields
For pt. I see ibid., vol.3, p.1915 (1991). The paper reports spectroscopic studies of Cr 3+ ions in fluorozirconate. fluoride, borate and telluride glasses in which the average strength of the octahedral crystal field Dq/B varies from 1.6 to 2.4. The emission spectra are shown to be inhomogeneously broadened by disord…
New mechanism of defect production in metals: A molecular-dynamics study of interstitial-dislocation-loop formation in high-energy displacement cascades
We present molecular-dynamics computer-simulation studies of 25-keV displacement cascades in Cu at low temperature. We observe the splitting of a cascade into subcascades and for the first time show by molecular dynamics that cascades in metals may lead to the formation of both vacancy and interstitial dislocation loo…
Relaxation time of confined liquids under shear
Ultrathin films of simple nonpolar molecular fluids (3--8 segmental dimensions thick) show a strikingly long relaxation time in response to oscillatory shear when confined between mica plates at 27 \ifmmode^\circ\else\textdegree\fi{}C. When the shear rate exceeds this inverse time, the effective viscosity decays as an…