Materials Literature
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The pressure P derivative dT C /dP of the Curie temperature T C , the linear magnetostriction Delta l/l at 4.2 K, the lattice parameters a and c as functions of temperature T and the high-temperature paramagnetic susceptibility chi of CrTe have been measured. The value of dT C /dP is found to be -7.0+or-0.2 K kbar -1…
Epitaxial La0.5Sr0.5CoO3 films with very smooth surface morphology were grown on (100) SrTiO3 and (100) MgO substrates by pulsed laser deposition. Scanning tunneling microscopy reveals that the thin film is formed by the coalescence of many aligned square mesas. The growth proceeds from the edges of terraces which are…
We have used Raman scattering to evaluate thick epitaxial GexSi1−x layers with 0.20≤x≤0.43 grown on Si (100) substrates. We show that a detailed consideration of the composition dependencies of the relative intensities of the various phonon modes can enhance the sensitivity of Raman scattering to variations in composi…
Fullerene tubular structures can be generated by vapor condensation of carbon on an atomically flat graphite surface. Scanning tunneling microscope (STM) images revealed the presence of tubes with extremely small diameters (from 10 to 70 angstroms), most of which are terminated by hemispherical caps. Atomic resolution…
X-ray microanalysis is a widely used technique in studies of cell and tissue elemental composition. It has applications in many different areas of biology, including animal and plant cell physiology, medicine, pathology and studies on environmental pollution. The author presents an up-to-date look at the use of X-ray…
Quasiperiodic self-similar chains generated by substitutions (i.e. deterministic concatenation rules) and their diffraction spectra are analysed in a systematic fashion, from the viewpoint of the superspace formalism. A substitution acting on n objects generates quasiperiodic chains if, and only if, the associated sub…
Abstract The kinetic characteristics and the reaction conditions of photocross‐linking of low‐density polyethylene (LDPE) in the melt have been studied using benzophenone (BP) and its derivatives such as 4‐chlorobenzophenone (4‐CBP) as photoinitiator and triallyl cyanurate (TAC) as cross‐linker. The efficiency of the…
I. INTRODUCTION\nWetting refers to the macroscopic manifestations of molecular interaction\nbetween liquids and solids in direct contact at the interface between them.\nSuch manifestations include the formation of a contact angle at the solid/\nliquid/fluid interline, the spreading of a liquid over a solid surface (di…
Analysis, fabrication, and characterization of variable groove depth planar waveguide grating couplers are presented. A formula is derived to describe the grating groove depth variation necessary to produce an outcoupled beam of arbitrary profile. A variable depth grating for producing a Gaussian beam profile is fabri…
The mechanism of the cofactor-independent glutamate racemase from Lactobacillus has been studied. The possible formation of an acylenzyme intermediate during catalysis has been investigated using 18O-carboxyl labeled glutamate. The absence of any washout of label during racemization argues against intermediate formati…
Glutamate racemase has been purified more than 12,000-fold from Lactobacillus fermenti. The racemase gene has been cloned using standard hybridization techniques combined with a novel selection for in vivo glutamate racemase activity, and the racemase has been expressed in Escherichia coli as 20-25% of the total solub…
The occurrence of alternative structures for the lithium, sodium, and potassium salts of poly(dG-dC) was determined as a function of hydration using IR spectra of nonoriented gels. Poly(dG-dC).K with added KCl (r = 0.56 where r is the moles of KCl per mole of nucleotide residue) gave results essentially identical to t…
Abstract A compatibilization strategy for poly(ethylene terephthalate) (PET) and polyethylene (PE) blends to achieve high toughness is described. Maleic anhydride functionalized styrene–ethylene–butylene–styrene (MA‐ g ‐SEBS) block copolymer at 20 pph was found to produce an intricate multidomain morphology in which t…
On macroscopic length scales observable by naked eye, or even on the scale of a few microns accessible with optical microscopes, the most prominent feature of dynamic wetting is the wetting line where the advancing fluid/fluid interface seems to intersect the solid surface at a measurable dynamic contact angle 9/). Fi…
Near-edge- and extended-x-ray absorption fine structure measurements, as well as luminescence excitation and emission spectra, were obtained from samples of porous Si and siloxene. Combined, these data establish that, contrary to a recently proposed explanation, siloxene is not generally responsible for the observed r…
We have discovered that a thin film of SiO2 can be directly reduced to Si under electron beam irradiation. The application of this effect to the fabrication of nanometer-sized Si dots and wires is demonstrated. In particular, if SiO2 is irradiated with a high intensity 100 keV electron beam of nanometer scale, then a…
The long wavelength hydrodynamics of films with unidirectional translational order adsorbed on fluid surfaces (as in a Langmuir monolayer) is formulated. We find the hydrodynamic frequencies \ensuremath{\omega}(q)\ensuremath{\propto}(\ifmmode\pm\else\textpm\fi{} \ensuremath{\surd}3 -i)${\mathit{q}}^{14/9}$ ${\mathrm{c…
The incubation time (ti) for the onset of porous Si formation by stain etching in HF:HNO3:H2O was observed to be a strong function of dopant type and concentration. For B-doped p-Si, ti increased significantly with substrate resistivity (ρ), from ∼0.5 min for 0.004 Ω cm to ∼9 min for 50 Ω cm. P-doped n-Si substrates e…
The authors present detailed investigations of vibrational modes in a hierarchy of rational (or commensurate) approximants to icosahedral quasicrystals based on exact diagonalization of the dynamical matrix and recursion calculations of the vibrational spectrum. The results demonstrate the existence of well defined lo…
Fragmentation of the actin binding glycolytic enzyme, aldolase, with cyanogen bromide yields an 18K actin binding fragment which corresponds to residues 1-164 of the aldolase sequence. Within this fragment there is a region of sequence (residues 32-52) which is highly homologous to a region of sequence near the C-term…