Materials Literature
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The astonishing smoothness of the superdeformed rotational spectrum in $^{152}\mathrm{Dy}$, from I=22 to I=60, is used as a basis for inferring a liquid-to-solid transition as the centrifugal force drives the nuclear shape into a closed-shell configuration.
The most significant feature in the transition from the quasicrystalline to the amorphous state is the loss of long-range bond-orientational order. Disclinations are candidates for elementary excitations which destroy angular correlations. Generalizing the topological defect classification, we investigate point singul…
The electrical conduction in thin-film diamond synthesized by microwave plasma enhanced chemical vapor deposition has been studied with metal-diamond-silicon metal-insulator-semiconductor structures. Measurements over a wide temperature range provide evidence for space-charge-limited current in the presence of traps.…
We show that large piezoelectrically induced electric fields strongly modify the optical properties of [111] growth axis strained-layer superlattices with growth axis along [111]. These internal fields reduce the superlattice band gap, change optical matrix elements, and cause a spatial separation of photoexcited elec…
Diamond thin films have been formed by dc plasma chemical vapor deposition with a high growth rate (∼20 μm/h). The diamond has been grown from methane (CH4) and hydrogen (H2) mixed gases on Si and α-Al2O3 substrates at a pressure of 200 Torr without surface scratching by diamond or c-BN powder. The obtained films have…
A two-dimensional Euclidean plane can be identified with the Gauss-Argan plane, so that a two-dimensional triangular lattice can be identified, apart from a scaling factor, with a set of 'triangular integers' of the complex quadratic field associated with a complex cubic root of 1. It is shown that a two-dimensional m…
The luminescence spectra and decay curves of Sb 3+ -doped Cs 2 NaMBr 6 (M=Sc,Y,La) are presented. In this lattice the Sb 3+ ion (5s 2 ) is octahedrally surrounded by six bromide ions. The emission consists of one band. The Stokes shift increases in going from Sc to La. This is connected to the larger space available f…
((NH4)1–xKx)2SO4 powdered crystals with x = 0.0, 0.1, 0.15, 0.25, 0.32, 0.6, 0.7, and 1.0 are studied by X-ray diffraction from room temperature down to 73 K. It is found that the mixed crystals are isomorphous to (NH4)2SO4 and K2SO4. The phase transition temperature decreases with the increase of the substituted ions…
Cross-slip of partial dislocations via the formation of stair rod dislocations at the line of intersection of two {111} planes is studied. General formulae are derived for the calculation of activation energies. It is shown that local stress concentrations due to a pile-up or a microtwin tip makes such cross-slip proc…
Magnetic susceptibility of an organic ion-radical salt, triethylammonium[TCNQ] 2 , has precisely been measured in the temperature range between 4.2 and 360K. It shows a shallow but obvious dip near 215 K. Such anomaly in the susceptibility of the salt has been found for the first time. The anomaly may result from the…
ABSTRACT This paper describes a recently developed standardized system for dull grading natural diamond, PDC, and TSP (Thermally Stable Polycrystalline diamond) bits, otherwise known as fixed cutter bits. The new system is consistent with the recently revised dull grading system for roller bits. It describes the condi…
The transmission spectra of the amorphous semiconductor system (${\mathrm{GeS}}_{2}$${)}_{\mathrm{x}}$(${\mathrm{As}}_{2}$${\mathrm{S}}_{3}$${)}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$ are measured under hydrostatic pressure, and the dependence of the optical gap ${E}_{0}$ and the refractive index n on the pressure is s…
The CNDO/S3 molecular orbital model is applied to describe the electronic structure of aniline, (C6H5)NH2, emeraldine, (C6H5)N(C6H4)N(C6H4)NH(C6H4)NH2, its hydrogenated and dehydrogenated forms, and its singly and doubly protonated forms. The cation eigenvalue spectrum, i.e., density of valence states (DOVS), is found…
A recombinant plasmid carrying an 11 kb restriction-endonuclease-ClaI fragment of genomic DNA from Escherichia coli ML308 was constructed. This plasmid complements an aceA mutation. The plasmid encodes the structural genes of the glyoxylate bypass operon, namely malate synthase A (aceB), isocitrate lyase (aceA) and is…
X-ray scattering and electron-transmission microscopy of melt-spun Al-Si-Mn alloys reveal that the Al-Mn icosahedral phase itself can grow congruently over a range of composition varying from 16 to 20 at.?Mn, and Si atoms substitute Al atoms selectively. The Q dependences of linewidth \ensuremath{\Delta}Q suggest that…
Thin films of the C1b-phase Heusler alloy PtMnSb, prepared by rf sputtering and subsequent annealing, have been studied in order to assess the high magneto-optical Kerr effect of this compound. The room-temperature saturation magnetization (Ms) and coercive force (Hc) for PtMnSb thin films after being annealed at 500…
We present a model to explain the resonances in the photoemission cross section of a surface state as a function of photon energy. The model is based on an extension of the direct-transition model for bulk states, and should be applicable to a surface state with a long decay length. Energy broadening of the final stat…
Raman scattering and infrared studies are reported for the layer compound GaSe under hydrostatic pressures up to 4 GPa. The rigid-layer mode shifts towards higher frequencies with an initial pressure coefficient of 0.234 ${\mathrm{GPa}}^{\mathrm{\ensuremath{-}}1}$. The overall behavior is explained in terms of the vol…
Localized 3p excitations and their decay have been studied in 3d transition metals and their single-crystal oxides by using electron-energy-loss (EELS), photoemission, and resonant photoemission spectroscopies. Variation of the primary-electron-beam energy in EELS allows the resolution of threshold transitions from hi…
New series of ferroelectric liquid crystals with two chiral carbons or bulky molecular components at the chiral carbon are synthesized and are found to possess extremely large spontaneous polarization exceeding 2×10−7 C/cm2 and a dielectric constant larger than 7000. These compounds are stable and exhibit a novel diel…