Materials Literature
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1. Spectroscopy and Electronic Structure of Inorganic Solids 2. Energy Levels of Free Atoms and of Optical Centres in Crystals 3. Symmetry and Group Representation Theory 4. Radiative Transition Rates and Selection Rules 5. Electronic Centres in a Vibrating Crystalline Environment 6. Experimental Techniques 7. Colour…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPreparation of polymers with controlled molecular architecture. A new convergent approach to dendritic macromoleculesCraig J. Hawker and Jean M. J. FrechetCite this: J. Am. Chem. Soc. 1990, 112, 21, 7638–7647Publication Date (Print):October 1, 1990Publication History Publish…
The experimental data on the structure of and the structural defects and structural relaxation in amorphous metallic alloys are reviewed. The elastic and inelastic properties of amorphous metallic alloys and the effect of disorder in the arrangement of atoms on the ferromagnetic properties of amorphous metallic alloys…
How and why electron microscopes work the vacuum system SEM alignment procedures SEM operating procedures TEM alignment procedures TEM operating procedures Scanning techniques in the TEM.
The combination of spin-polarization detection with core-level photoemission to give spin-polarized electron spectroscopy for chemical analysis provides new information on the oxidation of an iron surface. During the initial stage of oxidation the predominant phase is of a ferrimagnetic \ensuremath{\gamma}-${\mathrm{F…
We have derived the tilt and surface shape-equilibrium equations for tilted chiral lipid bilayers (TCLB's) in analogy with cholesteric liquid crystals. On a cylindrical surface the field of tilt directions of TCLB molecules forms a right-handed helix with 45\ifmmode^\circ\else\textdegree\fi{} gradient angle for ${\mat…
A structure refinement of the decagonal quasicrystal ${\mathrm{Al}}_{70}$${\mathrm{Co}}_{20}$${\mathrm{Ni}}_{10}$ with the five-dimensional superspace group P10/mmm was made on the basis of single-crystal x-ray-diffraction data. The structure is a layer structure that consists of two kinds of layers stacked along the…
Indications for a crossover between two distinct dynamical regimes at a temperature ${\mathit{T}}_{\mathit{c}}$ above the glass-transition temperature ${\mathit{T}}_{\mathit{g}}$ are presented for simple supercooled liquids. (i) Relating diffusion coefficient D and reorientational correlation times \ensuremath{\tau} w…
We use transient optical hole burning and photoluminescence to investigate the static and dynamic electronic properties of 32-\AA{} CdSe quantum dots. We observe a number of discrete electronic transitions, resolve LO-phonon progressions, and obtain homogeneous linewidths and electron--LO-phonon couplings. We find tha…
It was found that two different crystal forms, namely a platelike α-form and a hairlike β-form, were obtained by cooling crystallization of quizalofop-ethyl dissolved in ethyl alcohol. The solubilities, supersolubility and stabilities of the two crystals were investigated. Two solubility curves for the α-form and the…
The aqueous preparation of supported niobium oxide catalysts was developed by using niobium oxalate as a precursor. The molecular states of aqueous niobium oxalate solutions were investigated by Raman spectroscopy as a function of pH. The results show that two kinds of niobium ionic species exist in solution and their…
Crystallization from solution is an important separation and purification process in a wide variety of industries. These range from basic materials such as sucrose, sodium chloride and fertilizer chemicals to pharmaceuticals, catalysts and specialty chemicals. The major purpose of crystallization processes is the prod…
Ribonuclease H digests the RNA strand of duplex RNA.DNA hybrids into oligonucleotides. This activity is indispensable for retroviral infection and is involved in bacterial replication. The ribonuclease H from Escherichia coli is homologous with the retroviral proteins. The crystal structure of the E. coli enzyme revea…
The bacterial tryptophan synthase bienzyme complexes (with subunit composition alpha 2 beta 2) catalyze the last two steps in the biosynthesis of L-tryptophan. For L-tryptophan synthesis, indole, the common metabolite, must be transferred by some mechanism from the alpha-catalytic site to the beta-catalytic site. The…
Using the boundary-integral formulation, we show that the fully isotropic model of eutectic growth in directional solidification supports solutions with a broken parity symmetry. These correspond to the tilted ``waves'' observed recently by Faivre et al. Our results are in good agreement with these experiments. For a…
The complete amino-acid sequence of the bovine olfactory epithelium adenosine 3',5'-cyclic monophosphate (cAMP)-gated channel has been determined by cloning and sequencing its cDNA. It exhibits a high degree of sequence homology with the cGMP-gated channel of rod photoreceptors, suggesting that cyclic nucleotide-gated…
Diamond (100) substrates have been fluorinated under ultrahigh vacuum conditions with both atomic and molecular fluorine. X-ray photoelectron spectra of the resulting samples indicate that atomic fluorine, F, reacts efficiently at 300 K producing a saturation coverage of about three quarters of a monolayer (one monola…
The variations of the electrical resistivity, the magnetization, and the grain boundary precipitates of a binary NiSn alloy system with Sn content up to 8 at% are investigated as functions of the annealing time at 773 K. For samples homogenized at 1325 K, clear grain boundaries are observed; the residual electrical r…
The influence of the substituents on the prefiring conditions of nickel ferrites from the system Nix1Cux2Cox3Znx4Mnx5Alx6Fex7O4 where 0.14 ≤ x1 ≤ 1;0 ≤ x2 ≤ 0.3; 0 ≤ x3 ≤ 0.06; 0 ≤ x4 ≤ 0.5; 0 ≤ x5 ≤ 0.06; 0 ≤ x6 ≤ 0.2; 1.8 ≤ x7 ≤ 2.1 is investigated. It is found that the prefiring conditions influence the resonance l…
Solid solutions of magnesium ferrite and magnesium titanate are prepared by ceramic technique from α-Fe2O3, TiO2, and magnesium oxalate by heating at high temperature followed by quenching or by slow cooling. The compounds crystallise in monophasic cubic spinel structure. The compounds are studied for their initial su…