Materials Literature
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Soap bubbles of long life (over 2 years) and large size (over 60 centimeters in diameter, 100 liters volume) have been produced from bubble solutions improved by the addition of water-soluble synthetic organic polymers such as polyvinyl alcohol or polyoxyethylene. The natural life can be defined as the time it takes f…
Single crystals of strontium oxide have been additively colored by heating them in strontium vapor at pressures from 0.35 to above 42 Torr in a range of temperature from 1391 to 1618\ifmmode^\circ\else\textdegree\fi{}C. An asymmetric optical absorption band was observed at room temperature which peaked at 2.50 eV and…
Magnetic property of CrSb 2 having marcasite structure was investigated by means of magnetic, X-ray and neutron diffractions, specific heat and electrical resistivity measurements. The magnetic susceptibility of CrSb 2 showed a maximum at about 550°K and it seems to be antiferromagnetic with a negative paramagnetic Cu…
The luminescence spectra of various polymers and solid-model compounds induced by 1-MeV electrons are reported and interpreted. The presence of enhanced triplet emission and absence of singlet emission from poly(p-xylene), poly(monochloro-p-xylene), and the model compound dibenzyl are interpreted on the basis of a mol…
Electrical resistivities as a function of temperature (−130° to 25°C) were determined on single crystals of cerium hydride ranging in composition from CeH1.94–CeH2.85. Measurements were performed in an inert-atmosphere dry box using the four-point probe technique. Cerium hydride exhibited metallic behavior in the rang…
Single crystals of Ni2+-doped spinel were made by using a large solar furnace in our laboratory, and their absorption spectra were measured in near-infrared, visible, and ultraviolet regions. The observed bands were analyzed according to the crystal-field theory in which the spin–orbit coupling was taken into account,…
Phase stability relations among four hexagonal perovskite-like structures as well as the cubic perovskite structure have been studied for several oxides (BaMnO 3 and SrMnO 3 ) and fluorides (CsMnF 3 , RbNiF 3 and TlNiF 3 ) at high pressure. A series of high pressure transformations are found to occur in the order of t…
The electronic energy band structures of SnTe, GeTe, and PbTe are calculated including spin-orbit interactions. The resulting band structures are used to discuss some of the electronic properties of these crystals and to calculate the intervalley deformation potential for electron-phonon scattering in SnTe. The value…
Cu-Ni alloys contain clusters of one type of atom. These clusters have a mean size of 44 atoms in an almost equiatomic alloy, annealed for 50 h at 300\ifmmode^\circ\else\textdegree\fi{}C. At least 18% of the alloy undergoes this segregation. These results are in accordance with many physical properties of these alloys…
A simple model is proposed which relates the anharmonic motion of the bond charge to the higher order nonlinear susceptibilities. Excellent agreement with experiment is found for both the second- and third-harmonic coefficients.
We have observed nth order ($n=1,2,\ensuremath{\cdots},9$) Raman scattering in CdS under conditions of resonance between the laser frequency and the band gap or the associated exciton states. The frequency spectrum of these higher order processes demonstrates that the phonons involved are localized within a small volu…
A detailed discussion of the emission spectrum of trivalent chromium-europium pairs is given. Emission originating on the chromium $^{2}E_{g}$ level and terminating on the $^{7}F_{J}$ levels of neighboring europium ions has been observed for $J=1 \mathrm{through} 6$. Good agreement is obtained with the $^{5}D_{0}$ to…
This paper reports new data on the hydrostatic-pressure dependence of the conductivity and static dielectric constant, as well as new Hall-effect data taken over a wide temperature range, in the perovskite-oxide ferroelectrics KTa${\mathrm{O}}_{3}$, SrTi${\mathrm{O}}_{3}$, BaTi${\mathrm{O}}_{3}$, and $\mathrm{K}{\math…
The transition temperature ${T}_{c}$ of $\mathrm{SrTi}{\mathrm{O}}_{3\ensuremath{-}x}$ is calculated as a function of the electron concentration. The effective electron-electron interaction has an attractive part caused by the intravalley exchange of soft optical phonons that have been observed in the tetragonal phase…
It is shown that dielectrically defined average covalent and ionic energy gaps, ${E}_{h}$ and $C$, respectively, can be used to predict crystal structures and absolute band energies in crystals of formula $\mathrm{AB}$ with eight valence electrons per atom pair.
A study was made of the oxidizing behavior at high temperature (800°–1,800°C) in vacuum of UC, UN and U(C,N) samples containing added oxygen in excess amounts, through observations of gas release, X-ray diffraction analysis, and microphotography. The oxidation in vacuum of UC and U(C,N) was found to proceed above 1,20…
Spike-like magnetic domains play several important parts in the magnetization processes occurring in a hysteresis cycle, especially in a material magnetized in an easy direction of magnetization, such as transformer sheet. This theory is applicable to the spike domains observable in bulk magnetic materials but not, un…
The diffusion of trivalent gallium into the rock salt lattice of MgO has been investigated. This has been a first attempt at studying a diffusion process which involves both defect formation and the formation of a new phase, MgGa 2 O 4 , with a moving interface. The study was performed on pre-sintered MgO and β-Ga 2 O…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTInfrared spectra of the surface species produced by reactions of ammonia with germania gelManfred J. D. Low and Kunichi MatsushitaCite this: J. Phys. Chem. 1969, 73, 4, 908–910Publication Date (Print):April 1, 1969Publication History Published online1 May 2002Published iniss…
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