Materials Literature
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The last twenty-five years has seen enormous advances in both our imderstanding of liquid crystals and our ability to use them in applications.Early on during this period, it was possible for a person working in the field to be aware of most of the results, both pure and applied.Midway through this period, it was stil…
Covalently linked chromophore–quencher complexes are widespread in the area of transition-metal photochemistry and as models for photosynthesis. This review surveys recent examples of supramolecular complexes in which interacting chromophore and quencher fragments are instead held together by non-covalent interactions…
The thermoelectric properties of a mixed oxide (Zn 1-x Al x )O (x=0, 0.005, 0.01, 0.02, 0.05) are investigated in terms of materials for high-temperature thermoelectric conversion. The electrical conductivity, σ, of the oxide increases on Al-doping by more than three orders of magnitude up to ca. 10 3 S cm -1 at room…
We present calculations of head to head domain wall structures in magnetic strips of Ni/sub 80/Fe/sub 20/ with widths, w, ranging from 75 nm to 500 nm and thicknesses, t, from 1 nm to 64 nm. Neglecting magnetocrystalline and magnetostrictive anisotropy energies, minimization of exchange and magnetostatic energy leads…
Nitrogen adsorption measurements were performed over a wide range of relative pressures (10 -6 −0.995) for a series of siliceous MCM-41 samples obtained using alkyltrimethylammonium surfactants with different chain length. Both high- and low-pressure adsorption data were analyzed. The pore size was shown to increase i…
The phase behavior of organically passivated 20−75 Å diameter Ag and Au nanocrystals is investigated by examining surface−area isotherms of Langmuir monolayers and transmission electron micrographs of Langmuir−Blodgett (LB) films. The effects of temperature, organic passivant chain length, and nanocrystal size and com…
Multilayer superlattices incorporating colloidal metal nanoparticles have been synthesized by an approach based on self‐assembly. Teh method of synthesis is described and the results are presented from X‐ray reflectivity measurements, optical spectroscopy, and various microscopies, showing that they provide a consiste…
Electroluminescence and liquid crystallinity : these are the properties of a new spacerless conjugated main‐chain liquid‐crystalline (LC) polymer reported here. The thermal and spectroscopic properties of the new glass‐forming poly‐fluorene with octyl side chains (see Figure) are described, showing that polarized elec…
The oxidation kinetics of CVDSiC were monitored by thermogravimetric analysis (TGA) in a 50% H 2 O/50% O 2 gas mixture flowing at 1.4 cm/s for temperatures between 1200” and 1400°C. Paralinear weight change kinetics were observed as the water vapor oxidized the SiC and simultaneously volatilized the silica scale. The…
This paper deals with recent and important developments in the field of organic materials for second-order nonlinear optics. Attention is drawn to current trends in chromophore design with a discussion of current progress and problems in this field. A number of important classes of chromophores, such as one-dimensiona…
Abstract This paper is a guide to the ANSI standard C code of CASINO program which is a single scattering Monte CArlo SImulation of electroN trajectory in sOlid specially designed for low‐beam interaction in a bulk and thin foil. CASINO can be used either on a DOS‐based PC or on a UNIX‐based workstation. This program…
The tremendous advances made during the past decade in the chemistry, electrochemistry, physics, theory and processing of polyaniline and polypyrrole and their derivatives provide a broad solid foundation for future studies and technological applications. Selected examples of recent progress will be illustrated by: (i…
The reaction catalyzed by Escherichia coli dihydrofolate reductase (ecDHFR) cycles through five detectable kinetic intermediates: holoenzyme, Michaelis complex, ternary product complex, tetrahydrofolate (THF) binary complex, and THF.NADPH complex. Isomorphous crystal structures analogous to these five intermediates an…
Under certain conditions, a resonance phenomenon can occur in waveguide grating structures. Such structures have multilayer configuration, the most basic of which is comprised of a substrate, a thin dielectric layer or semiconductor waveguide layer, and an additional transparent layer in which a grating is etched. Whe…
Typical derivations of the Bragg equation in introductory texts do not adequately explain why x-rays are reflected as if by a mirror by crystal planes, and often lead to the mistaken idea that lattice points can be identified with the centres of atoms or ions in the structure. The treatment offered here is a little mo…
High-power ultrasound can generate cavitation within a liquid and through cavitation provide a source of energy which can be used to enhance a wide range of chemical processes. Such uses of ultrasound have been grouped under the general name sonochemistry. This review will concentrate on applications in organic synthe…
This text relies on only introductory level physics and chemistry as the foundation for understanding liquid crystal science. Liquid crystals combine the material properties of solids with the flow properties of fluids. As such they have provided the foundation for a revolution in low- power, flat-panel display techno…
Electrochromic materials are currently attracting much interest in academia and industry for both their fascinating fundamental spectroelectrochemical properties and their commercial applications. A large number of electrochromic materials are available from all branches of synthetic chemistry. In this review some of…
The What and the Why of Fibrous Composites. Concepts of Solid Mechanics. 3--D Constitutive Equations. Plane Stress Constitutive Equations. Lamination Theory. Test Methods. Material Response. Interlaminar Stresses. Failure and Damage. Laminated Tubes. Micromechanics. Appendices. Indexes.
Organisms have been producing mineralized skeletons for the past 550 million years. They have evolved many different strategies for improving these materials at almost all hierarchical levels from Ångstroms to millimetres. Key components of biological materials are the macromolecules, which are intimately involved in…