Materials Literature
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X-ray reflectivity from the surface of a nematic liquid crystal is interpreted as the coherent superposition of Fresnel reflection from the surface and Bragg reflection from smectic order induced by the surface. Angular dependence of the Fresnel effect yields information on surface structure. Measurement of the intens…
The deep-inelastic electron-scattering cross sections per nucleon ${\ensuremath{\sigma}}_{A}$ for D, He, Be, C, A1, Ca, Fe, Ag, and Au were measured in the kinematic range $0.09<~x<~0.9$ and $2<~{Q}^{2}<~15$ ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^{2}$ with use of electrons with energies ranging fro…
Measurement of transient photoconductivity in $a$-${\mathrm{As}}_{2}$${\mathrm{Se}}_{3}$ through the glass transition temperature ${T}_{g}$ gives the temperature dependence of the density of recombination centers. The activation energy of this density increases suddenly at ${T}_{g}$, leading to identification of the c…
Transient-charge-technique transport measurements have been made on pure strontium titanate. The trapping times at low temperature and the drift mobility for temperatures between 100 and 400K have been measured. It is found that the drift mobility is activated at high temperature and that, for one sample, it increases…
Eleven cases of tardive dyskinesia associated with metoclopramide have been reported to the Swedish Adverse Drug Reactions Advisory Committee from 1977 to 1981, 10 of which developed during the past three years. All patients were women, with a mean age of 76 years. Median duration of treatment before the onset of symp…
The occurrence of different Mn centres in single crystals of ZnSe and ZnS as well as in ZnS powder is reinvestigated. Besides the well-known centres of single crystals a new axial Mn2+ centre in ZnS is observed, and the formation of Mn2+–Mn2+ pairs is detected not only for ZnS but also for ZnSe. The influence of a Mn…
We studied the metal $d$ and O $2p$-derived electronic states of Ru${\mathrm{O}}_{2}$, Ir${\mathrm{O}}_{2}$, ${\mathrm{Ru}}_{0.65}$${\mathrm{Ir}}_{0.35}$${\mathrm{O}}_{2}$, and ${\mathrm{Ru}}_{0.77}$${\mathrm{Ir}}_{0.23}$${\mathrm{O}}_{2}$ by photoemission spectroscopy with synchrotron radiation. Our data are in quali…
Pyroelectric properties of α-LiIO3 in the temperature range between 320 and 120 K are measured. It is found that α-LiIO3 has low dielectric constant, low tan δ, and useful pyroelectric properties at low temperature about 125 K. The primary and secondary pyroelectric contributions at 253 K are estimated.
The first pressure derivatives fo the elastic moduli for three austenitic stainless steels, AISI 304, 310, and 316, have been determined from the variation of the sound velocity under pressure. All pressure derivatives are lower than the corresponding ones for pure iron. The elastic Grüneisen constant, derived from th…
X-ray investigations performed on the rotator phases of n alkanes CnH2n+1 with 26≤n≤34 prove that their structures are different from those exhibited by lower-numbered compounds. Two kinds of phases with monoclinic and triclinic symmetries are encountered both with the molecules tilted with respect to the layer plane.…
A new tight-binding band calculation is presented for the layer compound boron nitride which correctly describes the widths of both $\ensuremath{\sigma}$ and $\ensuremath{\pi}$ bands. The binding energy and wave function of the B $1s\ensuremath{\rightarrow}2p$ core exciton are studied. The core exciton is found to be…
Electrical properties, such as dielectric, resistive, ferroelectric, and piezoelectric properties, of bismuth layer-structured ferroelectrics (BLSF) are studied on grain orientation prepared by the hot-forging (H.F.) method. The BLSF compound which can stand the high temperature poling process is Pb(1−x) (NaCe)x/2 Bi4…
Zinc oxide films were prepared on unheated glass substrates by rf magnetron sputtering under an applied external dc magnetic field in pure argon gas, and electrical and optical properties of the deposited films were investigated. Highly transparent films with resistivity as low as 10−4 Ω cm, which were weakly oriented…
We consider a semi-infinite superlattice structure, with constituent $A$ characterized by dielectric constant ${\ensuremath{\epsilon}}_{A}(\ensuremath{\omega})$ and constituent $B$ by ${\ensuremath{\epsilon}}_{B}(\ensuremath{\omega})$, and examine collective excitations of the system in the absence of retardation effe…
High-resolution infrared absorption and photoconductivity spectra of several S- and Se-related donor centers in silicon are presented. These include isolated, probably substitutional, impurities and impurity pairs, as well as more complex centers. The spectra of the isolated impurities are consistent with ${T}_{d}$ sy…
The effective-mass-approximation differential equations appropriate for impurities in a graphite host are constructed and are used to solve self-consistently for the screening response surrounding a single intercalant atom. The screening cloud is found to have a very slow algebraic decay with a characteristic length o…
Abstract The siliceous cell wall of diatoms is formed in a silica deposition vesicle that is delimited by a membrane, the silicalemma. Once the siliceous wall matures, it is expelled and a new plasmalemma is formed underneath. Underlying wall formation is a multitude of events and processes, some of which are now know…
Abstract The minerals of biology have two components, one of which is inorganic and the other organic. Understanding rests initially in the description of the factors that control the nucleation and growth of the inorganic components in the absence of organic materials, and in the study of the organic materials in the…
Collagen is the principal organic matrix in bone. The triple helical region of the molecule is 1014 amino acids long. In fibrils these molecules are staggered axially by integers of 234 residues or 68 nm (D). This axial shift occurs by self-assembly and can be understood in terms of a periodicity in the occurrence of…
Abstract Coccoliths are delicate calcified structures produced by marine unicellular algae. In the species Emiliania huxleyi the calcium carbonate (mostly calcite) is closely associated with a complex, acidic polysaccharide which binds calcium ions specifically, interferes with the in vitro crystallization of calcium…