Materials Literature
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The behavior of a two-dimensional orientation field has been studied directly in space and time. In a freely suspended thin film of tilted smectic liquid crystal the local projection onto the film plane of the molecular orientation averaged through the film forms a two-dimensional (2D) vector field C^(x,y) with local…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTRemarkably inert metal alkyl linkages in alkyl dioxo complexes of molybdenum and tungstenPeter Legzdins, Everett C. Phillips, Steven J. Rettig, Luis Sanchez, James Trotter, and Vivien C. YeeCite this: Organometallics 1988, 7, 8, 1877–1878Publication Date (Print):August 1, 19…
Methods are described for the analysis of electron micrographs of regular biological objects. Fourier-based processing of one-dimensionally ordered arrays is described by way of introduction, before analysing two-dimensional crystals in projection with the aim of enhancing signal:noise ratio and thus of feint features…
Abstract The infrared absorption spectra of a palygorskite sample from Cáceres, Spain, showed two previously unreported bands in the OH-stretching region at 3420–3440 and 3220–3230 cm −1 after evacuation at 90°–230°C. These bands, which reached maximum intensity after the sample was heated at 150°C, were assigned to O…
Crystallization of an MgO‐Al 2 O 3 ‐SiO 2 ‐ZrO 2 sintered glass frit was studied. Heat treatment at 850° or 900°C caused initial crystallization of μ‐cordierite and tetragonal ( t ) ZrO 2 . The t ‐ZrO 2 crystallized with an irregular dendritic morphology and could be transformed to monoclinic ( m ) symmetry under cert…
The crystal chemistry of 16 groups of multiple‐chain, sheet, and framework silicates is reviewed. Crystal structure drawings are presented to illustrate crystal chemical features necessary to interpret chemical data for each mineral group. The 16 silicate groups considered in this review are the amphibole; nonclassica…
LCAO-CPA theory is applied to substitutionally disordered ferromagnetic BCC FeCo alloys. Calculations are based on charge and spin self-consistent LCAO parameters determined for the pure component metals within the local spin density functional theory. Effects of charge and spin self-consistency on the alloy magnetisa…
Simultaneous measurements of load, deformation and diameter were performed on stretched collagen fiber bundle from rat tail tendon using a dynamic, electronically controlled stretch system and a novel computer based electroptical set-up. A parallel analysis of glycosaminoglycan (GAG) concentration in the bathing solut…
We present the phase diagram of a binary system of two nematogenic terminal, non-polar compounds in which an induced smectic A phase appears over a large concentration–temperature range. X-ray measurements give evidence that the layer spacing, d, of this induced smectic A phase is clearly larger than the average molec…
The magnetic properties of Fe-Mn-Al alloys in the disordered phase are investigated through the M\"ossbauer technique. The magnetic phase diagram in the bcc structural phase is obtained as a function of the Al concentration ($q$) and Mn concentration ($x$). The site-diluted Ising model proposed in a previous study of…
The existing problems of the current methods for fabric handle evaluation are analyzed and as an alternative, a new measure, the weighted Euclidean distance (WD) value, of total handle is proposed. Using this method, one can specify the preferences of fabric handle. The whole process for deriving and calculating this…
The diatom genus Libellus Cleve was erected for naviculoid species with numerous girdle bands, L. grevillii (CA. Ag.) Cleve being the type species of the genus. The structure of this species has been compared with that of Navicula tripunctata (Müll.) Bory, the type of Navicula Bory. There are considerable structural d…
Japanese nickel titanium (NiTi) alloy wire possesses excellent spring-back properties, shape memory and super-elasticity. In order to adapt this wire to clinical use, it is necessary to bend as well as to control its super-elastic force, and so a direct electric resistance heat treatment (DERHT) method was developed.…
Photoluminescence properties of Mg- or Zn-doped Ga 0.5 In 0.5 P grown by metalorganic vapor phase epitaxy were studied as a function of hole concentration ( p ). The band-gap energy ( E g ) value for Mg- or Zn-doped Ga 0.5 In 0.5 P, grown under a condition in which undoped Ga 0.5 In 0.5 P shows an anomalously low E g…
Precise x-ray measurements of the tilt angle near the $\mathrm{Smectic}\ensuremath{-}A\ensuremath{-}\mathrm{Smectic}\ensuremath{-}{C}^{*}$ tricritical point show clear evidence of mean-field to tricritical crossover behavior; the mean-field region shrinks to zero at the tricritical point.
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTMorphology of segmented polybutadiene-polyurethane elastomersChi Li, Steven L. Goodman, Ralph M. Albrecht, and Stuart L. CooperCite this: Macromolecules 1988, 21, 8, 2367–2375Publication Date (Print):August 1, 1988Publication History Published online1 May 2002Published iniss…
The redox chemistry of Cu(II)-S(IV) complexes is examined, and the rate of reduction of Cu(II) is determined. The reduction of Cu(II) is shown to proceed via Cu^(II)_2SO_3^(2+) and Cu^(II)SO_3OH^+ intermediates. Copper(I), SO_4^(2-), and a mixed-valence compound, Cu^(II)SO_3Cu^l_2SO_3.2H_2O, are determined to be the p…
The mechanisms of interaction between a twin boundary and dislocations created during the deformation of a bicrystal are analysed by means of HREM. It is shown, on an atomic scale, that intrinsic dislocations enter the grain boundary where they decompose into discrete grain-boundary dislocations with Burgers vectors b…
The mesenchymal tissue component of the teleost pectoral fin bud has been explanted onto microfabricated quartz discs containing patterns of regular grooves of dimensions similar to those encountered by contact-guided cells in the intact fin system. Computer-aided analysis of cell migration on five separate patterns,…
Cyclotella species from several Canadian lakes have been investigated and their morphology illustrated by light and electron microscopy. Cyclotella antiqua W. Smith, C. bodanica var. bodanica Grun., C. bodanica var. affinis Grun., C. meneghiniana Kütz. and C. michiganiana Skvortzow have been identified with certainty…