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Bibliografía

Resistencia química del hormigón. XIV.- Contribución al estudio del sistema: Cemento P-450-Y hidratado-disolución de sulfato de magnesio

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Apostillas al trabajo de P. Dutron "La respuesta de la industria cementera problemas económicos y técnicos actuales” (1)

Distribution of Iodine in Doped Polyacetylene Filme

The distribution of iodine in polyacetylene doped under conditons typical for most published work is investigated by energy dispersive X-ray analysis under an electron microscope. The 9.1 GHz dielectric constant of a series of iodine doped (CH)x is measured as a function of temperature. From the X-ray analysis we conc…

Electronic Excitations in Polyacetylene

Recent experimental results on light scattering and absorption in polyacetylene are reviewed, and interpreted in terms of the soliton model. The data indicate that injection of an electron-electron (hole-hole) pair by chemical doping or photoinjection of an electron-hole pair invariably distort the lattice leading to…

La respuesta de la industria cementera a los problemas económicos y técnicos actuales

Transport, Magnetic and Structural Studies of Polyacetylene

Experimental progress is reviewed with emphasis on magnetic and transport studies. The magnetic results are fully consistent with the soliton doping mechanism; the decrease in Curie-law contribution has been demonstrated; the Pauli term remains small (Y < 0.07) and is apparently zero in the limit of completely uniform…

Reaction between nitrogen oxide (NOx) and ammonia on iron oxide-titanium oxide catalyst

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTReaction between nitrogen oxide (NOx) and ammonia on iron oxide-titanium oxide catalystAkira Kato, Shimpei Matsuda, Tomoichi Kamo, Fumito Nakajima, Hiroshi Kuroda, and Tsuneo NaritaCite this: J. Phys. Chem. 1981, 85, 26, 4099–4102Publication Date (Print):December 1, 1981Publ…

Responses of cat corneal sensory receptors to mechanical and thermal stimulation.

1. The afferent responses evoked by mechanical and thermal stimulation of the cat cornea were recorded extracellularly from strands of long and mixed ciliary nerves under deep anaesthesia. 94% of the units studied (n = 53) responded consistently to both stimuli. 2. Conduction velocities, measured by electrical stimula…

Epitaxial crystallization of polyethylene on organic substrates: A reappraisal of the mode of action of selected nucleating agents

Abstract Electron microscopy and electron diffraction studies show that polyethylene crystallizes epitaxially onto crystals of homologous series of (i) condensed aromatic hydrocarbons and (ii) linear polyphenyls. The contact planes of the PE chain‐folded lamellae with the (001) faces of the substrate crystals are foun…

The Continuous Damage Theory of Brittle Materials, Part 1: General Theory

The paper focuses on the establishment of the damage law consistent with the adopted physical interpretation of the damage. The model is developed within the framework of the general thermodynamics theory. In addition, the model incorporates a rigorous mathematical description of the damage growth kinematics including…

Lanthanide ion luminescence probes of the structure of biological macromolecules

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTLanthanide ion luminescence probes of the structure of biological macromoleculesWilliam D. Horrocks, Jr. and Daniel R. SudnickCite this: Acc. Chem. Res. 1981, 14, 12, 384–392Publication Date (Print):December 1, 1981Publication History Published online1 May 2002Published inis…

Unit-cell refinement from powder diffraction scans

A procedure for the refinement of the crystal unit cell from a powder diffraction scan is presented. In this procedure knowledge of the crystal structure is not required, and at the end of the refinement a list of indexed intensities is produced. This list may well be usable as the starting point for the application o…

Polymorphic transitions in single crystals: A new molecular dynamics method

A new Lagrangian formulation is introduced. It can be used to make molecular dynamics (MD) calculations on systems under the most general, externally applied, conditions of stress. In this formulation the MD cell shape and size can change according to dynamical equations given by this Lagrangian. This new MD technique…

Raman study of orientational dynamics of sulphate ions in potash alum Dattagupta,

The A g internal mode of the sulphate ion in potash alum is studied by Raman scattering as a function of temperature. This mode shows a splitting on account of the fact that a small fraction of S-O bonds point towards K + while a larger fraction point towards Al 3+ . The area under each peak is a measure of the number…

Biodegradation of Polyurethanes Derived from Polycaprolactonediols

Earlier studies on the biodegradation of synthetic polymers were initiated by the desire to avoid biodegradation, thereby obtaining long lasting materials. Disposing of nondegradable synthetic polymers after use is a problem that grows more serious every day. Designing the polymer to be biodegradable avoids the proble…

Potts model and phase transition in lead phosphate Pb3(PO4)2

An attempt is made to explain the first-order phase transition (180.4 degrees C) and the presence of an intermediate phase (180.4 degrees C-300 degrees C) between the para- and ferro-phases in lead phosphate, Pb 3 (PO 4 ) 2 , by invoking the basic ideas of the three-dimensional renormalised Potts model. This involves…

Scattering properties of ferroelectric domain walls

Ferroelectric domain walls have recently been considered as candidates for the occurrence of non-linear (soliton) excitations and roughening transitions. By means of X-ray or neutron scattering experiments, the domain walls may be observed directly and their width may be measured. The occurrence of a roughening transi…

Elastic scattering of low-energy electrons by neon atoms

Differential elastic scattering of electrons at 7.5, 10, 12.5, 15, 17.5 and 20 eV from neon is reported. The s, p, d and f phaseshifts derived from the measured cross sections are also presented.

Anomalous Frequency-Dependent Conductivity of Polyacetylene

The frequency ($f$) and temperature ($T$) dependent conductivity ($\ensuremath{\sigma}$) is reported for cis-${(\mathrm{CH})}_{x}$, trans-${(\mathrm{CH})}_{x}$, and ammonia-compensated ${(\mathrm{CH})}_{x}$. A strongly $T$-dependent dc $\ensuremath{\sigma}$ together with a weakly $T$-dependent ac $\ensuremath{\sigma}$…