Materials Literature
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is a petrographic term used to indicate highly birefringent, fine-grained, micaceous material that is viewed under the optical microscope. Other analytical techniques, including X-ray diffraction (xno) analysis, transmission-electron microscopy (reu), and chemical analysis, reveal that sericite from the Silverton cald…
A weighted form of the Durbin–Watson d statistic [Durbin & Watson (1971). Biometrika, 58, 1–19] has been used to quantify the serial correlation between adjacent least-squares residuals in Rietveld refinements of step-scan powder diffraction data. Analyses of X-ray and neutron data from a range of materials have shown…
The glass formation region in the yttria‐alumina‐silica system was investigated. Properties of glasses containing 25 to 55 wt% yttria were measured and the effect of the composition was determined. The density, refractive index, thermal‐expansion coefficient, and microhardness increased with increasing yttria content.…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSurface ordering phenomena in block copolymer meltsGlenn H. FredricksonCite this: Macromolecules 1987, 20, 10, 2535–2542Publication Date (Print):October 1, 1987Publication History Published online1 May 2002Published inissue 1 October 1987https://pubs.acs.org/doi/10.1021/ma00…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTGreatly enhanced second-order nonlinear optical susceptibilities in donor-acceptor organic moleculesH. E. Katz, K. D. Singer, J. E. Sohn, C. W. Dirk, L. A. King, and H. M. GordonCite this: J. Am. Chem. Soc. 1987, 109, 21, 6561–6563Publication Date (Print):October 1, 1987Publ…
The melting temperatures of natural and synthetic monazite and xenotime (rare‐earth ortnophosphates) were measured, using a heliostat‐type solar furnace. The results obtained are as follows: natural monazite from Japan (2057°40°C), synthetic monazite RPO 4 (R=La, 2072°20°C; R=Ce, 2045°20°C; R=Pr, 1938°20°C; R=Nd, 1975…
The alumina‐silica phase relations of samples annealed in oxygen and quenched were studied by optical microscopy, image analysis, X‐ray diffraction, and the electron microprobe. The solid solution boundaries of mullite changed with increasing temperature and joined at 1890°C and a composition of 77.15 wt% alumina. The…
The content of type I and III collagen in normal human skin from subjects of different ages was studied by means of a new high performance liquid chromatography method and by SDS-polyacrylamide gel electrophoresis and scanning electron microscopy. The ratio of types I and III collagen in covered skin remained constant…
Transformation toughening in ZrO 2 ‐containing ceramics is discussed. Specifically, microstuctures of the three distinct types of ZrO 2 ‐toughened ceramics are presented, after which microstructural evolution in MgO‐partially‐stabilized ZrO 2 Mg‐PSZ) is reviewed. The mechanical properties of such transformation‐toughe…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTInfluence of oxidation state, pH, and counterion on the conductivity of polyanilineWalter W. Focke, Gary E. Wnek, and Yen. WeiCite this: J. Phys. Chem. 1987, 91, 22, 5813–5818Publication Date (Print):October 1, 1987Publication History Published online1 May 2002Published inis…
A quantitative study of the electronic properties of layered compound 2H-TaS 2 and its Li, Pb and Sn intercalation complexes has been made. The authors report the self-consistent band structures obtained using the LMTO method. The results show that the rigid-band model is essentially correct for 2H-LiTaS 2 but is an o…
The advances in acid catalysis by heteropolyacids are examined and data on the acidity of heteropolyacids are surveyed. The characteristics of homogeneous and heterogeneous acid catalysis by heteropolyacids are discussed and its applied aspects are noted. The bibliography includes 116 references.
It was found that the Ga addition to NdFeCoB magnets was very effective for improving their magnetic properties. Magnets with high boron concentration had a high coercive force and magnets with low boron concentration had a high-energy product. The following magnetic properties were obtained: (1) Nd14.5FebalCo16Ga1B9.…
We present optical-absorption data together with band-structure calculations for the polaron lattice and bipolaron lattice for the highly conducting form of polyaniline, proton-doped polyemeraldine. We show that the polaron-lattice band structure fully accounts for the observed optical transitions. These results are i…
ABSTRACT In recent years, gyp (calcium sulfate) scale removal techniques have become increasingly complex and the number of fluids and additives have continually grown. The purpose of this paper is to provide the field engineer with the fundamental understanding of the calcium sulfate removal procedures and the roles…
ABSTRACT Calcium Carbonate (CaCO3) is one of the most common scales in oil field operations. Various fluids (brine, oil and gas) can mix in the reservoir and/or wellbores under drastically varying sets of thermodynamic, kinetic and hydrodynamic conditions that will affect the carbonate scale forming tendencies. Many o…
Abstract The subtitutional doping of 120‐Å‐ sized TiO 2 Particles with Fe( III )ions has a profound effect on the charge carrier recombination time in this colloidal semiconductor. In undoped particles, the mean lifetime of an electronhole pair is ca. 30 ± 15 ns. Doping with 0.5% Fe( III ) drastically augments the cha…
Fr\"ohlich and Peierls showed that a one-dimensional system with a half-filled band can lower its ground-state energy by a dimerization from period 1 to period 2. It was an open question whether or not this dimerization was exact, i.e., whether additional symmetry breaking would further lower the energy. We prove that…
Calculations using nonlocal density-functional theory show that the total energies of atoms in states characterized by partially filled degenerate subshells are substantially lower when the charge density is not spherically averaged. This is in contrast to the case with local density theory in which spherical and nons…
By pseudopotential methods the electronic properties of quasicrystalline metal are examined from the nearly-free-electron viewpoint. The procedure results in the appearance of band gaps associated with each quasicrystal reciprocal-lattice vector, and these lead to singularities in both the density of states and the jo…