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Solid State compatibilities in CaO-CaO∙Al2O3-CaF2 system

In open atmosphere the two phases containing fluorine, C11A7∙CaF2 and 3CA∙CaF2, laying in the CaO-CaO∙Al2O3-CaF2 were synthesized. The synthesis of the 3CA∙CaF2 at 1.100°C was possible without loss of F, when the stoichiometric mixture of CA and CaF2 was pressed into tablets and was applied vacuum, avoiding in such a…

Determination of the efficacy of two water repellents applied to granite

We evaluated the efficacy of two water-repellents applied to three types of granitic rock widely used in building construction and restoration in Galicia (NW Spain). The depth of penetration of the water-repellents was determined by measuring capillary absorption by the treated rock. The efficacies of the water-repell…

Relación entre la resistencia a compresión de probetas-testigo y probetas normalizadas

Criteria about concrete Strength Resistance of DRILLED STANDARDIZED specimens have been considered and occasionally explained by several authors in some of their work, but there is no publication devoted to the full extent of the subject,, reason why we are trying to put together results/ideas, expose them, and briefl…

Elaboration of α’L-C2S form of belite in phosphatic clinker. Study of hydraulic activity

Solid state synthesis associated to X-ray diffraction and free lime analysis have been carried out to determine proper conditions (chemical compositions, optimum time and temperature of burning) under which phosphatic belitic clinker is elaborated. Raw meals, at low lime saturation factor and added phosphate, can form…

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Structure and phason energetics of Al-Co decagonal phases

We develop a model for Al-Co decagonal quasicrystals and approximants. Our model defines a large number of potential atomic positions. These sites are populated by two atomic that interact with each other through electronic-structure-based pair potentials. Monte Carlo simulation of the model produces realistic atomic…

Oxygen Consumption byDesulfovibrioStrains with and without Polyglucose

The kinetics of oxygen reduction by Desulfovibrio salexigens Mast1 and the role of polyglucose in this activity were examined and compared with those of strains of D. desulfuricans and D. gigas. Oxidation rates were highest at air saturation (up to 40 nmol of O(2) min mg of protein) and declined with decreasing oxygen…

Coalescence and overgrowth of diamond grains for improved heteroepitaxy on silicon (001)

Heteroepitaxial [001]-oriented diamond films with considerably increased lateral grain size and strongly improved orientational perfection could be prepared by microwave plasma-assisted chemical vapor deposition using a [001]-textured growth process on Si (001) substrates followed by a [110] step-flow growth process.…

Numerical Simulation of Zener Pinning with Growing Second‐Phase Particles

The Zener pinning effect with growing second‐phase particles in Al 2 O 3 ‐ZrO 2 composite systems were studied by two‐dimensional (2‐D) computer simulations using a diffuse‐interface field model. In these systems, all second‐phase particles are distributed at grain corners and boundaries. The second‐phase particles gr…

Increased glass transition temperature in motionally constrained semicrystalline polymers

A large number of experimental results in the literature support and illuminate a model of behavior of chains and chain segments in the amorphous phase of semicrystalline polymers connecting the elevation of the glass transition temperature (Tg) above its normal value to several kinds of motional restrictions imposed…

Self-polarization effect in Pb(Zr,Ti)O3 thin films

The self-polarization effect is investigated in Pb(Zr,Ti)O3 (PZT) thin films deposited by sol-gel and magnetron sputtering techniques. The effective piezoelectric coefficient of as-grown films, which is proportional to their initial polarization (self-polarization), is measured by a sensitive interferometric technique…

Multivariate analysis of statistically poor EDXRD spectra for the detection of concealed explosives

Energy dispersive x-ray diffraction (EDXRD) has been developed as a tool for the detection of explosives in passenger baggage. The measured spectra result from the combined diffraction from each of the materials within a scattering volume. Multivariate regression was used to identify known components within very noisy…

Fluid particle model

We present a mechanistic model for a Newtonian fluid called fluid particle hydrodynamics. By analyzing the concept of ``fluid particle'' from the point of view of a Voronoi tessellation of a molecular fluid, we propose a heuristic derivation of a dissipative particle dynamics algorithm that incorporates shear forces b…

Emulsion Polymerization Process for Organically Soluble and Electrically Conducting Polyaniline

An emulsion process has been developed for the direct synthesis of the emeraldine salt of polyaniline (PANI) that is soluble in organic solvents. The process entails formation of emulsion particles with a mean hydrodynamic diameter of 150 nm and consisting of a water-soluble organic solvent (e.g., 2-butoxyethanol), a…

Transparent conducting ZnO thin films prepared by XeCl excimer laser ablation

Highly conductive and transparent aluminum- and gallium-doped zinc oxide (ZnO:Al and ZnO:Ga) thin films in place of indium tin oxide films have been prepared by using XeCl excimer laser ablation at relatively low temperatures. The impurity content of Al or Ga in the ZnO target was optimized on the basis of the measure…

Three‐Dimensional Computer Simulation of Ferroelectric Domain Formation

Three‐dimensional (3‐D) computer simulations of ferroelectric domain formation and evolution were performed, using a computer simulation model based on the time‐dependent Ginsburg‐Landau equations. A cubic‐to‐tetragonal ferroelectric phase transition is considered. It is shown that the initial stage of the transition…

Electronic Structure and Elastic Properties of Strongly Correlated Metal Oxides from First Principles: LSDA + U, SIC-LSDA and EELS Study of UO2 and NiO

We compare experimentally observed electron energy loss spectra (EELS) of uranium dioxide UO2 and nickel monoxide NiO with the results of ab-initio calculations carried out by using a method combining the local spin density approximation and the Hubbard U term (the LSDA + U method). We show that by taking better accou…