Materials Literature
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A method is described for measuring the mass/length or mass of molecular assemblies by comparative electron scattering in the STEM. Standard particles whose mass is well established (e.g. TMV or fd bacteriophage) are deposited on the electron microscope grid together with the sample to be measured. Images containing a…
The luminescence properties of the Bi 3+ ion as an activator in the series of compounds and vary considerably with the host lattice composition. The Stokes shift of the emission varies from 1500 cm −1 in the case of to 12,800 cm −1 in the case of . The large variation of the position of the emission band is ascribed t…
Raman scattering and optical depolarization measurements have been employed in investigations of the phase transition induced by the substitution of lithium for potassium in KTa${\mathrm{O}}_{3}$ to form ${\mathrm{K}}_{1\ensuremath{-}x}{\mathrm{Li}}_{x}\mathrm{Ta}{\mathrm{O}}_{3}$. Lithium concentrations as high as 5.…
Abstract Various microwave plasma treatments were applied to Kevlar in the form of multifilament fabric and single fiber. Plasma‐modified fabrics were used to construct two‐ply laminates using a triazine resin adhesive. Very significant increases in the bond strength of laminates may be attributed to the plasma treatm…
We present a method for measuring linear electrooptic coefficients involving comparative measurement of interferometric phase-modulation indices at wavelength λ = 6328 Å. The accuracy of the method (8–16%) varies according to the crystalline quality. We have investigated a new nonlinear crystal, 3-methyl 4-nitropyridi…
We present a novel electrostatic, energy-dispersive particle analyzer whose astigmatism can be used to measure the polar angle distribution of charged particles originating in a sample spot, in a multichanneling mode. The analyzer consists of a toroidal prism and a truncated conical lens, both coaxial on an axis throu…
Abstract A new series of aromatic‐aliphatic polyesters of general structure: magnified image R 1 = terphenyl, biphenyl, stilbene R 2 = (CH 2 ) n ; CH 2 C(Me) 2 CH 2 ;CH 2 ;C(Et) 2 CH 2 ; (CH 2 CH 2 O) n CH 2 CH 2 has been synthesised. The existence of thermotrpic liquid crystalline phases has been shown…
Abstract Details of the thermal behavior, including transition temperatures, transition heats and transition entropies, are reported for three series of nematic liquid‐crystalline “backbone” polyesters having the general structure magnified image All polysters described above were examined by differential scanning cal…
A relationship Is(φ) that is valid for arbitrary temperatures T ≲ Tc and thicknesses of d of the N layer is established for clean SNS sandwiches in the case when the Fermi velocities of the normal (vN) and the superconducting (vs) metals are related by the strong inequality vN ≪ vs. Dependences of the critical current…
The performance of insulators as determined by artificial tests for various contaminant levels at voltage levels ranging from 200 to 1000 kV dc are presented along with comparisons to field measurements. Included are the effects of polarity, insulator shed design, insulator spacing, and uniform and non-uniform contami…
Some experiments are reported on the bubble textures obtained in homeotropically aligned cholesterics of large pitch. The variations of the bubble diameter with the thickness and the temperature of the liquid crystal and with an applied electric field are studied. The conditions of the texture erasure by application o…
The fluorescent emission and scattering spectra of metallic lithium and lithium fluoride were obtained by using continuous radiation from the Institute for Nuclear Study synchrotron in the energy region of 40-80 eV. The spectrum of metallic lithium is in close resemblance with the one obtained by an ordinary electron…
Electron microscopy and diffraction techniques for studying grain‐boundary structure are reviewed. The experimental conditions for applying strong‐beam, weak‐beam, and lattice imaging and electron diffraction are described and examples from recent studies in ceramics, semiconductors, and metals are used to illustrate…
Warburg’s law, which describes the distribution of the current density over the plane electrode for a point to plane steady corona discharge, is derived. The derivation is based on a model using hyperboloid point to plane geometry with a constant charge carrier mobility model and a time independent potential. The deri…
Co 6 C(CO) 12 S 2 (I) has been isolated in crystalline form from the mixture of more than a dozen of carbonyl products formed when Co 2 (CO) 8 reacts at room temperature with CS 2 . Crystals of I are monoclinic with space group Cc , and lattice constants a 16.250(5), b 9.413(4), c 16.036(5) Å, β 116.77(4)°. St…
Abstract Small‐scale qualitative tests were used to screen 185 inorganic powders for flame and inhibiting effects upon cellulose. Nearly half of the compounds inhibited smoldering. These were limited to inorganic salts whose anions include boron, phosphorus, sulfur or halogen. Over half the compounds inhibited flaming…
The interlayer exchange coupling, J′, between magnetically inequivalent ions in adjacent layers has been studied by EPR in the quasi-two-dimensional salts of (CnH2n+1NH3)2CuCl4 where n = 1,2,3. The Cu2+ ions of the CuCl42− complexes in adjacent layers of these salts have slightly different g tensor orientations and, i…
Abstract Empirical reaction progress diagrams showing the trends of major element oxide concentrations (in g/cm 3 ) as functions of bulk density for a diabase saprolite reveal discontinuities in the trends of Al 2 O 3 , MgO, H 2 O+, and nonextractable Fe 2 O 3 . The discontinuities coincide with discontinuities in the…
Abstract Polarized Raman spectra of single crystals are observed for the room-temperature phase NH4NO3(IV). The spectra in the low-frequency lattice vibration region as well as in the internal vibration region are well interpreted based on D2h13 structure. Raman spectra of powdered samples are measured at various temp…
The spin-spin relaxation time T2 for natural rubber (NR) and NR-synthetic low cis-polyisoprene rubber (IR) mixture vulcani-zates with various crosslink density vs under various extension ratios α has been measured by pulsed NMR. The T2 for the sample becomes shorter with increasing α and the dependence of log T2 on α…