Materials Literature
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In science we like to emphasize the novelty and originality of our ideas. This is harmless enough, provided it does not blind us to the fact that concepts rarely arise out of nowhere. There is always a historical context, in which isolated precursors of the idea have already appeared. What we call “discovery” sometime…
An array-type universal profile function for powder-pattern fitting is described. It is defined as an array of unknown parameters representing the profile heights at discrete angular steps. The unknown parameters are determined during least-squares fitting together with the integrated intensity, the peak position, the…
Far-infrared reflection spectra of a polycrystalline sample of monoclinic CuO were measured in the frequency range from 30 to 700 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ at temperatures between 10 and 300 K. The six observed lattice vibrational modes at 147, 161, 321, 478, 533, and 587 ${\mathrm{cm}}^{\mathrm{\ensu…
This extensive materials selection and application book is the first of its kind. It describes a comprehensive treatment of all forms of high temperature corrosion problems encountered in industry, especially gas turbine and aerospace, heat treating, mineral and metallurgical processing, ceramic, electronic and glass…
A theoretical model of fatigue in ferroelectric thin-film memories based upon impact ionization (e.g., Ti+4 to Ti+3 conversion in PbZr1−xTixO3), resulting in dendritic growth of oxygen-deficient filaments, is presented. The predictions of spontaneous polarization versus switching cycles Ps(N) are compared with both Mo…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAnion-exchange reactions of layered double hydroxidesMartina Meyn, Klaus Beneke, and Gerhard LagalyCite this: Inorg. Chem. 1990, 29, 26, 5201–5207Publication Date (Print):December 1, 1990Publication History Published online1 May 2002Published inissue 1 December 1990https://p…
A ferroelec. and ferroelastic monodomain single crystal of BiFeO3 at space group R3c is rhombohedral, with a 5.57874(16), c 13.8688(3) .ANG.; arh 5.6343 .ANG., arh 59.348 Deg; d. (calcd.) = 8.337 for Z = 6. Final R = 2.4, Rw = 1.9% for 422 reflections. The structure can be described as a rhombohedrally distorted simpl…
Polyhydroxyalkanoates (PHAs), of which polyhydroxybutyrate (PHB) is the most abundant, are bacterial carbon and energy reserve materials of widespread occurrence. They are composed of 3-hydroxyacid monomer units and exist as a small number of cytoplasmic granules per cell. The properties of the C4 homopolymer PHB as a…
The scanning tunneling microscope has been used to image a reduced TiO(2)(110) surface in ultrahigh vacuum. Structural units with periodicities rangng from 21 to 3.4 angstroms have been clearly imaged, demonstrating that atomic resolution imaging of an ionic, wide band gap (3.2 electron volts) semiconductor is possibl…
Correlations have been sought between Mossbauer spectral parameters and several crystal structure properties of Mg-Al oxide and silicate minerals hosting iron cations as minor constituents. Plots of isomer shift (I.S.) versus various bond length-related parameters, including mean metal-oxygen distance (R) of a coordin…
INTRODUCTION to the PHOTOTROPHIC BACTERIA and the USE of ELECTRON MICROSCOPY in THEIR STUDY. INTRODUCTION. PHOTOTROPIC PROKARYOTES. Introduction. Oxygenic Phototrophs. Cyanobacteria. Chloroxybacteria. Anoxygenic Phototrophs. Purple Phototrophs. Green Phototrophs. Heliobacteria. ELECTRON MICROSCOPY. Introduction. Scann…
A transition of brittle to ductile propagation of a sharp crack in a crystal is observed by molecular-dynamics simulation and the transition mechanism shown to be the emission of dislocations at the crack tip and activation of specific slip systems appropriate to the crystal structure. Implications for extension of cu…
Three series of dilute iron alloys, with oversized solutes, FeTi, FeV and FeMo, in the concentration range 50 at.ppm to 3 at.%, have been electron-irradiated at low temperature together with the metal. A strong dependence of the solute and defect resistivities on the solute concentration is observed, which is analysed…
An adaptive hysteresis current control technique where the hysteresis band is automatically modulated by the input voltage integrator without the load information to maintain the modulation frequency nearly constant is presented. The computer simulation for the proposed current controller has been done and the results…
With respect to the investigation of low pressure filament-assisted chemical vapor deposition processes for diamond formation, absolute concentrations of atomic hydrogen were determined by two-photon laserinduced fluorescence in the vicinity of a heated filament in an environment containing H(2) or mixtures of H(2)and…
An imaging Raman system based on a 2-D detector and capable of collecting simultaneously 1024 spatially resolved spectra has been constructed. Hardware and software are described which allow real time analysis of the spectral data, leading to a large reduction in the data storage requirements. The analysis yields a 1-…
Single crystals of Cu and Al were irradiated with 2.4*10 18 fast neutrons/cm 2 (E>0.1 MeV) at 4.6 K. Asymptotic diffuse scattering of X-rays was measured after irradiation and after several annealing steps up to 300 K. The formation of dislocation loops of interstitial and vacancy type was observed; their size distrib…
Polycrystalline diamond films deposited by the microwave plasma chemical vapor deposition (CVD) technique onto quartz substrates have been irradiated with 100 keV C and 320 keV Xe ions at room temperature and at 200 °C. The dose dependence of the electrical conductivity measured in situ exhibited complicated, nonmonot…
Stable icosahedral ${\mathrm{Al}}_{85\mathrm{\ensuremath{-}}\mathit{x}}$${\mathrm{Cu}}_{\mathit{x}}$${\mathrm{Ru}}_{15}$ (15x20) alloys of good metals are characterized by conductivities below the ``minimum metallic value,'' and resistivity ratios \ensuremath{\rho}(0.5 K)/\ensuremath{\rho}(295 K) as large as 4. Strong…
A comparative investigation of the influence of crystl lattice type on the character of primary processes, following irradiation with fast neutrons or heavy charged ions with low energies, is carried out with b.c.c., f.c.c., and h.c.p. structures. It is found that in all the cases sub-threshold stage generation of poi…