Materials Literature
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Using a false twister for hollow spindle wrap yam spinning is supposed to facilitate operations. However, our investigation shows that a high level of false twist can sig nificantly influence yarn appearance and mechanical properties. Wrap yarn spun with a false twister has a tortuous structure, while wrap yarn spun w…
Abstract Synthesis and properties of urethane elastomer‐modified epoxy resins were studied. The urethane elastomer‐modified epoxy resins were synthesized by the reaction of a 4‐cresol type epoxy compound having hydroxymethyl groups (EPCDA) with isocyanate prepolymer. The structure was identified by IR, 1 H NMR and GPC…
X-Ray diffraction studies have been made of the crystalline luminescent material Na+–Er3 +β″-alumina for three different erbium ion concentrations; equivalent to 100, 72 and 26% substitution of Na+ ions (Na1+y–3xErxMgyAl11–yO17, for x= 0.56, 0.40 and 0.14, respectively, and y= 2/3). The results form thereafter a struc…
The variation of magnetic and loss characteristics of nonoriented silicon-iron sheets with frequency and temperature under sinusoidal magnetic flux-density conditions have been investigated using an Epstein frame. The investigations have made it possible to model the variation of iron loss with frequency and magnetic…
The solid-state conductivity, σ, has been determined for cyanophenyl paraquat (CPQ: 1,1′-bis(p-cyanophenyl)-4, 4′-bipyridilium), for salts containing dication and radical cation redox states and for mixtures of the two. A plot of σvs. mole fraction of CPQ+ showed a maximum corresponding to a composition [CPQ2+(CPQ+)2(…
Non-ionic amphiphilic compounds—butane-1.2,3-triol derivatives, 2-hydroxycarboxylic acids and carboxylic acids—incorporating rigid aromatic structural units like 1,4-disubstituted benzene, 4,4′-disubstituted biphenyl or the 2-phenyl-1,3,4-thiadiazole have been prepared. In most cases these compounds exhibit smectic li…
For identification of how explosion increases the reactivity of chitin and chitosan, changes in the crystalline polymorphism of these polysaccharides were studied by X-ray diffraction measurements. The α-chitin form of chitin did not change after being exploded, but an X-ray diagram of chitosan showed a hydrated cryst…
Vacuum ultraviolet(VUV) irradiation (wavelength 147 nm) of siloxane polymers in the presence of air was studied using ATR FTIR and XPS spectroscopy. The ATR FTIR study revealed the formation of CO and OH groups in the surface layer depending on irradiation time and air pressure. The concentrations of CO and OH groups…
The fast measurement of furrows or wrinkles requires the use of a non-contact device. We have chosen a laser detector based on a triangulation principle, using position-sensitive detectors. This apparatus has a sensitivity of about 2-3 microns for a vertical range > 1 mm; this vertical range can reach 8 mm. There is n…
Ultramafic materials weather rapidly to maintain relatively high saturation with exchangeable Mg, and they have very high Fe and high Mn contents. These features retard the translocation of humus compounds, which is essential for podzolization. Three soils in a range of ultramafic materials were sampled to relate thei…
Thermal-aged surveillance material was removed from two commercial reactor pressure vessels. The material from the first reactor vessel received a thermal exposure of approximately 103,000 hours at 282°C (540°F), while the material from the second reactor vessel received a thermal exposure of approximately 93,000 hour…
Abstract This article discusses the process considerations and deposit properties of nickel plating. It describes the Watts solution and the anode materials used. The article focuses on the nickel plating processes used for decorative, engineering, and electroforming purposes. It provides information on the quality co…
Mg-10mass%Gd and Mg-10mass%Dy alloys have high strength at high temperatures and exhibit good ductility. In this study, 1 or 2mass%Y or Nd was added to these binary alloys in order to increase high temperature strength and reduce the material cost, and the effect of the third alloying elements on their aging character…
This article reviews the various aspects of tannin, which is finding varied uses in leather industry and pharmaceutics.
The forsterite film in 3% Si steel is formed by a solid state reaction of the annealing separator, MgO, with SiO/sub 2/ that results from the reduction of the fayalite layer in the hydrogen atmosphere in the high temperature anneal. In this work, secondary recrystallization was about complete at 1000/spl deg/C. After…
Abstract The Raman scattering of MoO 3 at 300 and 77 K and the infrared reflectivity spectra of MoO 3 at 300 K have been investigated in different scattering geometries. The Raman spectra of PbMoO 4 crystals at 77 K have been investigated also. The reflectivity spectra of MoO 3 crystals were calculated for E ∥ c and E…
The dark red-purple nickel(IV) periodataes MNilO6(M = Na, K, Rb, Cs or NH4) have been prepared by peroxohexaoxodisulfate oxidation of mixtures of nickel(II) salts, MNO3 and periodate ions in hot aqueous solution. Powder X-ray diffraction studies showed that the structures adopted the space group P312, with hexagonal c…
The complex [{TcN(thiourea)}4(edta)2]·6H2O has been prepared and is shown to consist of a cyclic tetrameric Tc4N4 configuration with four asymmetrical TcN–Tc bridges; each diagonal pair of Tc atoms is bridged by an edta4–ligand and TcN distances range between 1.681(7) and 1.695(7)Å, with N–Tc of 1.977(7) to 2.009(7)Å.
Non-tert-butyl-substituted phenolic porphyrins 5, 7 and 9 undergo aerial oxidation in acidic and basic solutions. Radicals are produced whose singlet EPR spectra differ significantly from those observed for the tert-butyl-substituted phenolic porphyrin 1. In the radical derived from 5a, for example, the unpaired elect…
The structures of Na-containing nasicon-type phases of the form NaxMIIxMIII2 –x(SO4)3 –y(SeO4)y(0 ⩽x⩽ 1.5, 0 ⩽y⩽ 3) at 25 °C have been refined using powder neutron diffraction. The data are consistent with a rhombohedral structure similar to that of Na1 +xZr2SixP3 –xO12, but a reduction in symmetry (R compared to Rc)…