Materials Literature
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This paper shows that for magnetic resonance imaging (MRI) permanent magnet assemblies with the pronounced pole pieces, the investigation of magnetic field generated by one pole piece is a way to obtain an interrelation between pole piece diameter, magnet assembly air-gap length, and first and second shim dimensions.…
Using high resolution x-ray diffraction, the porous silicon lattice parameter was measured in vacuum, as a function of temperature in the range 90–300 K, showing that the thermal expansion of porous silicon is larger than that of bulk silicon. We then estimate the differential thermal expansion coefficient δα of p+-ty…
A high strength pure copper conductor was fabricated by a cryogenic drawing process at 77 K where the dynamic recovery of copper was reduced. With this method, drawn pure copper wire achieved a strength level of 580 MPa and a conductivity of more than 96% IACS at room temperature. This strength level is about 45% high…
We report detailed measurements of the magnetic behavior of La1−xBaxMnO3 bulk samples over a wide range of composition (0⩽x⩽1), temperature (4.2–775 K), and magnetic field strength (1 G–50 kG). The end members of this series namely LaMnO3+δ (with δ⩾0) and BaMnO3 crystallize into pseudocubic perovskite and hexagonal la…
XPS broad scans and high-resolution narrow-region spectra were collected from fresh realgar (As 4 S 4 ) surfaces to measure core level S and As binding energies. Reasonably accurate As and S concentrations were determined from XPS broad scans using peak areas and manufacturer supplied sensitivity factors. High resolut…
The synthesis of a new heterocyclic core has been developed. Its standard derivatisation afforded new types of FLC's and their physical properties were determined.
Both bacterial growth and corrosion involve electrochemical (charge-transfer) half-cell reactions which have been conveniently compared on the potential−pH (Pourbaix) diagram in this paper. We have tabulated bacteria which mediate or facilitate various pairs of these half-cell reactions in otherwise kinetically unfavo…
Examples of a pale blue corrosion product and associated corrosion on copper alloy artifacts from the collections of the British Museum Department of Egyptian Antiquities have been analysed and identified. A previously unreported compound, sodium copper acetate carbonate, has been identified.
The inhibition mechanism of N,N-dipropynoxymethylamine acetate on pure iron in H2 SO4 solution and its synergism with chloride was studied by potentiodynamic polarisation and electrochemical impedance techniques. Results showed that the inhibition mechanism was the mixed deactivation mechanism. Molecules of the inhibi…
New red oxide phosphors Y2O3:Eu3+,Si4+ and (Y,Gd)2O3:Eu3+,Si4+,Bi3+ are synthesized by a coprecipitation method. Relative cathodoluminescence (CL) brightness at low voltages (⩽1 kV) is analyzed. At the low voltage excitation, luminance of the synthesized phosphors is higher than that of other commercially available re…
In a polydisperse thermotropic main-chain liquid crystalline polymer, we observe the process of thermally induced nematic−nematic phase separation between short and long polymer chains. We study the dynamical features of this system, in particular the evolution of Schlieren textures formed by disclinations surrounding…
It has been widely known that both solute concentration, i.e., frictional effects, and stacking fault energy influence the degree of cross slip and slip planarity in face-centered-cubic alloys. Cross slip is preceded by constriction of two partial dislocations. A model is proposed for the energy required to form a con…
Hydroxylclinohumite Mg 9 [SiO 4 ] 4 (OH, F) 2 , a new mineral from Zelentsovskaya mine near Magnitka (Zlatoust district, Southwestern Urals), is the OH-dominant equivalent of clinohumite Mg 9 [SiO 4 ] 4 (F,OH) 2 . The crystal structure of hydroxylclinohumite has been refined from single-crystal X-ray data to R = 0.026…
Polysiloxanes bearing epoxy groups as lateral substituents were prepared by the hydrosilylation of 1-allyloxy-2,3-epoxypropane (allylglycidylether) with poly(hydrogenmethylsiloxane-co-dimethylsiloxane)s (DH-D copolymers) of various compositions. To determine the optimal conditions of the hydrosilylation catalyzed by h…
Solid-state 93 Nb static and MAS NMR and 93 Nb nutation studies of polycrystalline Pb(Mg 1/3 Nb 2/3 )O 3, (PMN) and (1 − x )Pb(Mg 1/3 Nb 2/3 )O 3 / x PbTiO 3 ( x = 0.05 to 0.50) solid-solutions are reported. The 93 Nb static and MAS NMR spectra of PMN measured at 14.1 T have two major resonances due to the central tra…
We consider a flat panel direct conversion x-ray image detector in which a photoconductor is used to directly convert absorbed x-ray photons to collectable electron hole pairs. The storage capacitor at each pixel stores a quantity of charge proportional to the incident radiation. The charge stored at each pixel is rea…
The aim of this paper is to present a general model of oriented continuum within the frame of Newtonian-Eshelbian continuum mechanics to describe macro- and microdeformations of solids taking into account the evolution of defects as voids and cracks. Within a manifold-theoretical setting, position- and direction-depen…
The physical characteristics and structures of the four commercial varieties of Indian silk fibres, namely Mulberry, Tasar, Eri and Muga, have been studied. It is observed that the silk filaments from the same cocoon show considerable variation in linear density. As one moves from the outer layers to the inner layers…
Brandholzite, a new magnesium antimony hydroxide hydrate mineral, Mg(H 2 O) 6 [Sb(OH) 6 ] 2 , has been discovered in Au-Sb-Quartz veins of the former mining district of Brandholz-Goldkronach, Fichtelgebirge, Germany. The new mineral is associated with stibnite and antimony-ochers and forms colorless, platelike crystal…
Cotton/polyester carpet materials are resistant to surface flame spread after esterification of the cellulosic fibers with polycarboxylic acid and suitable catalyst. The crosslinked cellulose-containing materials passed the re quired flammability standards for carpet when subjected to the methenamine pill test. This t…