Materials Literature
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To clarify the principles and mechanisms of water vapour transfer by diffusion in waterproof breathable fabrics for clothing, experiments using a simple glass dish were carried out under steady state conditions with and without a temperature gradient in the climatic chamber. It was found that both vapour pressure and…
A scanning tunneling microscopy study of the topology of thin films of SnO2 has been conducted. The films were deposited using dc reactive magnetron sputtering on microscope slides heated to 150°C. No annealing treatments were needed. For films of 125 Å to 2 000 Å, the grain size was proportional to the thickness of t…
From the absorption spectrum of CaF2:Ho3+, Judd–Ofelt intensity parameters were estimated as Ω2=0.018×10-20 cm2, Ω4=0.57×10-20 cm2, and Ω6=0.587×10-20 cm2. Radiative transition probabilities and radiative lifetimes were also estimated for some of the levels. We observed red-to-green, -blue, and -violet energy upconver…
The ATP-dependent phosphofructokinase (ATP-PFK) of Streptomyces coelicolor A3(2) was purified to homogeneity (1,600-fold) and characterized (110 kDa, with a single type of subunit of 40 kDa); it is allosterically inhibited by phosphoenolpyruvate. Cloning of the pfk gene of S. coelicolor A3(2) and analysis of the deduc…
Available data on embrittlement of duplex stainless steels (DSS) under cathodic protection (CP) in seawater, including some data previously unpublished, was reviewed. Results show hydrogen enters duplex alloys at typical protection potentials (–1 VSCE), but that the risk of failure is very low. The austenite phase ten…
ABSTRACT Browning and changes in the composition of sliced and whole carambola ( Averrhoa carambola L.) fruit during storage were investigated. Susceptibility to browning after slicing, packaging and storage for 4 wk at 4.4°C varied considerably between four cultivars and five selections. There was no difference in br…
This paper theoretically explores possible phase diagrams of the associating polymers in which macro- and microphase separation transitions coexist. Our model binary mixture consists of long chains (A) carrying f associative groups and short chains (B) carrying one associative group on their ends. Comb-shaped block co…
In a nematic liquid crystal where the director field has a splay-bend deformation mediated by the boundary conditions there is a certain intrinsic polarization density distribution characteristic of the flexoelectric properties of the medium. By application of an electric field perpendicular to the director, a twist i…
Formation of lead magnesium niobate (PMN) perovskite phase using a columbite type of precursor together with the addition of excess MgO has been investigated. When MgO and Nb 2 O 5 are reacted with 1:1 stoichiometry, a minor amount (}2%) of Mg 4 Nb 2 O 9 is formed along with the columbite‐type phase which in turn coul…
High-resolution transmission electron microscopy observations are presented of the motion of grain-boundary dislocations within an aluminium Σ = 3[011] bicrystal. The observations show the glide of dissociated a/3[111] grain-boundary dislocations on the incoherent Σ = 3(211) boundary. These dislocations are subsequent…
Leslie E. Sieburth, Elliot M. Meyerowitz, Molecular Dissection of the AGAMOUS Control Region Shows That cis Elements for Spatial Regulation Are Located Intragenically, The Plant Cell, Vol. 9, No. 3 (Mar., 1997), pp. 355-365
High voltage dc is required in a wide range of consumer, commercial, and military applications. Presently available PD analysis for dc systems can extend far beyond the old-fashioned "not more than 'n' PD pulses per minute over a given magnitude".
The development of advanced structural ceramics , which are used in specific components working under extreme conditions, require their microstructural analysis. The microscopy of structural ceramics is reviewed, beginning with various imaging techniques. The important microstructural features of three ceramics—alumin…
The semiconductor–metal phase change in VO 2 at approximately 67°C, which results in great changes in its optical, electrical, and magnetic properties, is described in detail. The synthesis of VO 2 thin films by the sol‐gel method is outlined and the structure and optical properties are characterized, including hyster…
A new analytic model, based on the interference of waves, and numerical calculations are exploited for analyzing the spectral behavior of the transmitted and reflected intensities from metal-based grating–waveguide structures. The results reveal that strong intensity changes can occur near resonance with resonance ban…
The best models available in the literature to analyze gelation in the diepoxide−cyclic anhydride copolymerization are based on the mean-field approach. A kinetic model was developed to account for the nonrandom steps of the copolymerization. Two kinetic schemes were employed with one including chain transfer steps. P…
All eukaryotic protein kinases share a conserved catalytic core. In the catalytic (C) subunit of cAMP-dependent protein kinase (cAPK) this core is preceded by a myristylation motif followed by a long helix with Trp 30 at the end of this A-helix filling a hydrophobic cavity between the two lobes of the core. To underst…
In order to better understand the gelation process associated with collagen assembly, and the mechanism of the in vitro morphogenetic phenomenon of "matrix-driven translocation" [S.A. Newman et al. (1985) Science, 228, 885-889], the viscosity and elastic modulus of assembling collagen matrices in the presence and abse…
Broad-band conductive spectroscopy covering a 10 mHz–1 GHz frequency range has been employed to examine the ionic motions in polypropylene oxide (PPO) complexed with 0–1% LiClO 4 at temperatures from -60 °C to 100 °C. The dc conduction appears as a plateau of the conductive spectra in their medium frequency range. As…
The present work showed a significant antinociceptive activity in the tannin fraction (TF) extracted from the bark of Myracrodruon urundeuva Fr. All. This inhibitory effect was demonstrated not only against abdominal contractions but also in the formalin test in mice. In the first case, at doses of 0.1 and 1 mg/kg, i.…