Materials Literature
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A new cavity model that can explain the interaction between viscous effects including vortices and cavitation bubbles is presented in this study. This model, which is named a bubble two-phase flow (BTF) model, treats the inside and outside of a cavity as one continuum by regarding the cavity as a compressible viscous…
Photopolymerization of polymer-coated solid substrates with linearly polarized light is shown to induce an anisotropic, uniaxial orientation of polymer molecules. The linearly photopolymerized (LPP) layers exhibit UV dichroism and optical anisotropy. The resulting anisotropic dispersive surface interaction forces are…
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” opt…
A consistent picture of the evolution of the defect structure is presented for a solid undergoing plastic deformation, when defects are multiplied and arbitrary hierarchical structures are formed. The complete problem is reduced to a description of the kinetics of the formation of a new structural level of plastic def…
Abstract This paper is concerned with the problem of modelling the motion of a bubble close to a rigid structure in an infinite fluid. It is well known that the boundary integral method is a powerful technique for modelling the motion of a single bubble in a fluid. In this paper we shall present a modified boundary in…
Asp222 is an invariant residue in all known sequences of aspartate aminotransferases from a variety of sources and is located within a distance of strong ionic interaction with N(1) of the coenzyme, pyridoxal 5'-phosphate (PLP), or pyridoxamine 5'-phosphate (PMP). This residue of Escherichia coli aspartate aminotransf…
Two distinctive 3,4-dihydroxyphenyl-L-alanine-(DOPA-) containing proteins (Pc-1 and Pc-2) have been isolated and partially characterized from the thorax of the reef-building sabellariid Phragmatopoma californica. They are the first such reported from the phylum Annelida. The proteins are presumed to be soluble precurs…
A single-crystal neutron diffraction study of the cubic Laves phase Fe2Zr at 4.2 K has been made using both polarized and unpolarized incident beams. The samples were prepared from high-purity zirconium and iron and exhibited resistance ratios (rho 293 K/rho 4.2 K) of typically 95, indicative of samples with good long…
Highly coercive isotropic magnets were prepared by pressure-assisted Zn bonding of microcrystalline Sm2Fe17Nx powders. Mechanically alloyed and two-step heat treated powder was mixed with elemental Zn powder and compacted by uniaxial pressing at elevated temperatures. The maximum room-temperature coercivity of such ma…
Changes in the electronic states for Ba1-xKxBiO3- delta ( delta =0 and 0.5) due to various surface treatments (fracturing, scraping and ion sputtering) have been studied by X-ray photoelectron spectroscopy. It is found that marked spectral changes occur as a result of scraping and sputtering; the core levels are broad…
The authors propose a consistent approach to the study of hole self-trapping and diffusion in ionic crystals based on the static quantum-chemical calculation of the self-trapping energy and adiabatic barriers or hole diffusion. The calculations made for MgO revealed the possibility that the hole is localized on one an…
Results of a study on internal stress, hardness, and structure of nitrogen-doped amorphous hydrogenated hard carbon films deposited by rf glow discharge from methane-nitrogen mixtures onto silicon substrate are presented. Films obtained for different N2 partial pressures (bias voltage Vb=−370 V and total pressure P=8…
Black and white images were projected onto n-type silicon (100) wafers during a photoelectrochemical etch to produce a color image that photoluminesces. The photoluminescence originates from a thin layer of luminescent porous silicon that is produced in the photoetch, and the colors that appear in the etched image ari…
Abstract Studies of the thermal and photodegradation of two commercial polymers, stabilized and unstabilized low‐density polyethylene (LDPE), show the effects of weathering in differential scanning calorimetry (DSC) curves. The shape and the size of the melting peak vary significantly in thermal aging and in accelerat…
Abstract Both sodium hydroxide solution of mercerizing strength and anhydrous methylamine are suitable pretreatments for enhancing the reactivity of cotton cellulose. Favorable results are achieved by maintaining the fiber material in the never‐dried state after the swelling treatment. Extraction by organic solvents i…
Abstract A fast electrochemical technique for the discrimination of one‐ and two‐electron mechanisms in the oxidative addition of alkylating agents (RX) to corrinato‐ and porphyrinatocobalt(I) ([Co I L]) is described. It is based on single‐scan voltammograms of [Co II L] in the presence of RX and variable amounts of t…
Abstract The socium cryptates of the macrobicyclic ligands 1–6 have been synthesized by direct macrobicyclisation or by stepwise procedures. They incorporate 2,2′‐bithiazole, 2,2′‐biimidazole, 2.2′‐bipyrimidine as well as 2,2′‐bipyridine units. Treatment of the sodium complexes with europium(III) chloride gave the cor…
An experimental electronic bandstructure of molybdenum disulphide has been determined from angle-resolved ultraviolet photoelectron spectroscopy (ARUPS) measurements: polar-angle-dependent ARUPS at a photon energy of 21.2 eV allows the authors to obtain an approximate plot of dispersion parallel to the basal face whil…
We report a new photoluminescence process in epitaxial Si1−xGex layers grown on Si by rapid thermal chemical vapor deposition which we attribute to the recombination of excitons localized at random alloy fluctuations. This luminescence is characterized by saturation at very low excitation densities (≂100 μW cm−2), ver…
The synthesis of SmCo5 by the chemical reduction of Sm2O3 during mechanical alloying has been investigated using x-ray diffraction, electron microscopy, and magnetic measurements. The mechanical alloying of Sm2O3 with Co and Ca resulted in the formation of CaO and an amorphous Sm-Co phase. The SmCo5 phase formed durin…