Materials Literature
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Conference International Symposium on the Chemistry of Natural Products, International Symposium on the Chemistry of Natural Products, ISCNP, Natural Products, VIIth, Riga, USSR, 1970-06-21–1970-06-27 Published Online: 2009-01-01 Published in Print: 1971-01-01 © 2013 Walter de Gruyter GmbH, Berlin/Boston
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Abstract Previous theories valid for polymer chains with large loops protruding into the solvent are developed. Interaction in various layers parallel to the interface is calculated according to the Flory‐Huggins theory. Excluded volume effects are shown to be so small that they can be neglected. The adsorption isothe…
The synthesis and the molecular structure of [NN′-o-phenylenebis(salicylideneiminato)UO2(EtOH)] are reported together with i.r. and relative stability data for similar complexes.
Thin foils of nickel have been electron-irradiated with the beam of a high-voltage electron microscope. In specimens previously ion-bombarded, voids are observed to grow at temperatures between 280°C and 480°C. The results are compared with those for neutron irradiation and are found to be basically similar. Differenc…
The permeation of H through iron and an iron‐nickel alloy as a function of time is reported. Below a certain critical H overpotential η, the H permeation occurs as a function of time in a simple way; and can be repeated indefinitely on the same specimen. But, when , the permeation‐time transient attains a new and char…
Abstract Ce(IV)‐induced polymerization of acrylonitrile and methyl methacrylate with acetylated cotton having different acetyl contents was investigated. The extent of interaction between the cotton and monomer is dependent upon the acetyl content of the former as well as on the reaction conditions. Increasing the ace…
The corrosion process for two iron samples of different purities in a molar solution of sulfuric acid has been studied by means of a rotating disk electrode. This study supports the previously formulated hypothesis which assigns the hysteresis, observed when corrosion is low, to the partial coverage (Θ) of the electro…
Barium titanate (BaTiO3) was deposited onto Pt foil, and onto thin-film Pt and Pt-Rh electrodes on sapphire, and counterelectroded to complete metal-dielectric-metal structures. Dielectrics (5000–60 000 Å) were deposited at substrate temperatures from 23 ° to 1000 °C, some fired in air at temperatures to 1400 °C after…
The Monte Carlo technique was applied to the fundamentals of the Electron Probe Microanalyzer (EPMA) and the Scanning Electron Microscope (SEM). A model based on the multiple scattering formula of Lewis was applied to simulate the scattering processes of the primary electrons in the specimen and was exemplified by com…
Expressions are derived for the rotational energy levels of a symmetric top molecule in a 2 E state which take into account a spin-orbit interaction and vibronic Jahn-Teller interactions. Some group theoretical aspects of the Jahn-Teller problem for a general symmetric top molecule are discussed. In addition, the over…
Second-harmonic generation experiments show that large optical nonlinearities are associated with isocyclic and heterocyclic organic groups. The nonlinearities in one compound of the pyrimidine family, 5-Nitrouracil, are estimated to be as large as in barium-sodium niobate.
Abstract The α to γ transition that occurs in nylon 6 upon iodine treatment was investigated by infrared spectroscopy, differential thermal analysis, and x‐ray diffraction techniques. Thin films of nylon (0.2 mil) were treated in either iodine–potassium iodide aqueous solution or in iodine vapor. Very short treatment…
Dispersion equations for shear waves propagating in a nematic liqid crystal are derived from the Ericksen and Leslie's hydrodynamic equations. The complex refection coefficient of a shear wave at a solid-nematic liquid crystal interface is related to effective viscosity coefficients depeding on the orientation of the…
Abstract Clay minerals occur most frequently in a state too finely divided for satisfactory observation with the best optical microscopes, or for study with single-crystal X-ray techniques. The higher resolution made possible by electron-optical instruments can therefore be put to good use in the investigation of the…
Using colloidal iron staining or post-fixation with ruthenium tetroxide it could be evidenced that the interstitial cells on the sensory areas in the inner ear in pigeons produce a fibrillar network sur- rounding every hair bundle of the sensory cells. This network ties the overlying membrane to the surface of the sen…
Phosphorescence microwave double resonance experiments are reported on Zn porphin at 1·2 K. In glassy solution very broad resonance transitions are observed. However, for Zn porphin in a crystalline n-octane matrix—a system known for its sharp optical spectra (Shpolskii effect)—three pairs of microwave transitions wit…
The structure of a new heteroaromatic sulphur compound has been determined; the results support the inclusion of d-orbital in CNDO molecular orbital calculations.
Abstract Molybdäncarbonyl‐Komplexe des NCCN‐Systems (1.4‐Diaza‐butadienDAB) zeigen eine antiparallel zum Grundzustandsdipolmoment gerichtete intensive farbgebende Elektronenanregung, deren an dreiunddreißig meist neuen Verbindungen untersuchte Solvatochromie direkte Aussagen über die Größe der Metall‐Ligand‐Termw…
Structural data and electronic properties argue against the existence of independent chains in the liquid state of tellurium. It is proposed here that the local order consists of sites with 2 or 3 first neighbours, joined by bonds with a strong covalent character. In space, that local order persists up to the second n…