Materials Literature
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The Landau levels for the $\ensuremath{\pi}$ bands of graphite are calculated using the Slonczewski-Weiss-McClure energy-band model. Bohr-Sommerfeld quantization is used to calculate two new types of magnetic energy levels which trigonal warping introduces. The method is valid for any magnitude of ${\ensuremath{\gamma…
We have solved Maxwell's equations for the fields localized near the surface of a doped semiconductor possessing either a depletion layer, an accumulation layer, or an inversion layer. We present the dispersion relation for the frequency of the surface plasmon polariton as a function of the wave vector parallel to the…
The contributions of monopoles, dipoles and quadrupoles to the electric field gradient at B sites of normal cubic spinels, ZnAl 2 O 4 , ZnFe 2 O 4 , CoAl 2 O 4 , MgAl 2 O 4 , CdFe 2 O 4 and WNa 2 O 4 have been calculated. From a comparison with experimental results, a coherent range of variation of the dipole polariza…
The intensity distribution on the specimen was computed by using the pupil function in terms of electron wave optics, and the spot size (defined as 80% of the total electron beam spread) was precisely obtained from this intensity distribution. From the computer simulation data the following results were obtained. (1)…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDetermination of molybdenum in plutonia cermets by x-ray fluorescence spectrometryH. A. Woltermann and W. W. StrohmCite this: Anal. Chem. 1974, 46, 12, 1822–1823Publication Date (Print):October 1, 1974Publication History Published online1 May 2002Published inissue 1 October…
Using as a starting point the atomic positions determined by potential energy calculations, the crystal structure of isotactic poly(p-fluorostyrene) has been determined from X-ray diffraction data. It is found that two chains having 4, helical conformations pack into a metrically orthorhombic unit cell with a = 17.6 Å…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTConductances, transference numbers, and activity coefficients of some aqueous terbium halides at 25.deg.Frank H. Spedding, Robert A. Nelson, and Joseph A. RardCite this: J. Chem. Eng. Data 1974, 19, 4, 379–381Publication Date (Print):October 1, 1974Publication History Publis…
The effects of Arochlor 5442 (a chlorinated terphenyl) dibutyl phthalate, butyl stearate, a high molecular weight polyester plasticizer, acetone, methyl ethyl ketone, isopropyl alcohol, carbon tetrachloride, and water on the dynamic mechanical properties of polycarbonate have been studied. Results show that all liquid…
Abstract During an investigation of the time for ignition of polymeric materials under the influence of radiant heating, it was found that the polymer surface reflectance‐absorptance characteristics were a major factor in the variance of the ignition times. A subsequent research study was made of the reflectance‐absor…
The early stages of crystallization in a lithium disilicate glass were studied by high-voltage transmission electron microscopy and diffraction at 1000 kV, using thin sections prepared from the bulk material. Heat treatment of the glass in the range 450°-500°C produced large numbers of internally-nucleated lithium dis…
The electronic structure of tetrathiofulvalene (TTF) has been determined from its photoelectron spectrum and the photoelectron data for the tetrahydro derivative of TTF and 1,3-dithiolane. Correlations of the ionization potentials (i.p.) and several molecular orbital calculations are used in the assignment of the phot…
A general method is developed for obtaining Clebsch-Gordan coefficients of finite groups. With this method Clebsch-Gordan coefficients are obtained in a matrix form, whereas the so-called basis-function generating machine generates these coefficients one by one. The method is applied to double point group D̄3, the poi…
Abstract The recrystallization of amorphous cellulose at various relative humidities was studied to clarify the relation between the amount of adsorbed water in cellulose and the molecular motion by the DSC method. The initial recrystallization kinetics of amorphous cellulose at various relative humidities were observ…
We report the waveguiding properties of sputtered films of three chalcogenide glasses: As(2)S(3), Ge(28)Sb(l2)Se(60), and Ge(33)As(l2)Se(55), at 1.064microm. Propagation losses of less than 1 dB/cm have been measured for As(2)S(3) films. Delineated guides, as well as films, have been made and studied.
Mechanisms of concentration quenching of green-Cu luminescence in hexagonal ZnS:Cu,Al under cathode-ray excitation are investigated. The observed concentration dependence of the luminescence intensity is explained well by a model assuming complete pairing of donors and acceptors. Interstitial Cu + centers are formed d…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStructure of potassium calcium hexanitrocuprate(II) at 295.deg.K. Evidence for a static Jahn-Teller distortionShozo Takagi, P. Galen Lenhert, and Melvin D. JoestenCite this: J. Am. Chem. Soc. 1974, 96, 21, 6606–6609Publication Date (Print):October 1, 1974Publication History…
Ultrasonic velocity measurements have been made on liquid Mg, Ca, Sr, and Ba to temperatures ~300 °C above the melting points. An empirical relationship between the sound velocity and surface tension is tested and found to hold well for the alkaline earth metals. Simple model calculations of the compressibilities at t…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSpin delocalization in square-planar spin-triplet benzene- and toluenedithiolatecobaltate(III)P. J. Van der Put and A. A. SchilperoordCite this: Inorg. Chem. 1974, 13, 10, 2476–2481Publication Date (Print):October 1, 1974Publication History Published online1 May 2002Publishe…
The eutectic between ZrO 2 and MgO was located at 27 wt% MgO. Directional solidification of this composition yields MgO rods in a cubic ZrO 2 matrix. Plane front growth occurred at solidification rates of <2.0 cm/h. The interfiber spacing was proportional to the inverse square root of the solidification rate. In sa…
A study is reported of the effects of the method of conversion of a fibre web into a non-woven fabric and of various constructional parameters on the air-permeability of the resultant fabric. It is shown that, within the ranges of measurement made, the factor most closely related to the air-permeability was the fabric…