Materials Literature
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Tlrroe-dimensional counter-collected X-ray and neutron single-crystal data have been used to refine the crystal structure of a tremoilite (N%.uotrG.us Car.sorxMgsxAl6.e2ssi?.,67)O,2(OHr.$rFo.ooClo.orz); a
The biosynthetic pathways of norvaline homoisoleucine were examined using regulatory mutants of leucine biosynthesis in Serratia marcescens. alpha-Isopropylmalate synthetase [EC 4.1.3.12], the first enzyme of leucine biosynthesis, catalyzed the condensations of acetyl-CoA with pyruvate, alpha-ketobutyrate, alpha-ketov…
Honoclinic sulfur is the form which is stable at normal pressure from 95°C to the melting point (115°).Below 95° the orthorhombic form ("rhombic sulfur") is stable, but pure crystals of the metastable monoclinic form can be preserved for weeks at room temperature.Sands 2 determined the structure of the monoclinic crys…
Summary Some properties of the collagens of myocommata and skin from three species of fish are described. The musculature of hake separates readily into flakes because of intrinsic weakness in the connective tissue. The corresponding tissue of catfish is unusually strong and holds the musculature together under almost…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTChromium(II) porphyrins and an irreversible dioxygen complexStephen K. Cheung, Carol J. Grimes, Janice Wong, and Christopher A. ReedCite this: J. Am. Chem. Soc. 1976, 98, 16, 5028–5030Publication Date (Print):August 1, 1976Publication History Published online1 May 2002Publis…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStructural isomers of 1:12 and 2:18 heteropoly anions. Novel and unexpected chiralityMichael T. PopeCite this: Inorg. Chem. 1976, 15, 8, 2008–2010Publication Date (Print):August 1, 1976Publication History Published online1 May 2002Published inissue 1 August 1976https://pubs.…
Using infrared spectroscopy, X-ray diffractometry, differential thermal analysis, scanning electron microscopy, solubility and dissolution rate measurements, it was demonstrated that the comminution of digoxin results in the appearance of an amorphous phase. The examination of spironolactone and 17 beta-oestradiol by…
Abstract X‐ray photoelectron (XPS or ESCA) spectra of the valence bands are measured from the monomeric β‐modification of H 2 Pc (H 2 C 32 H 16 N 8 ), FePc, CoPc, NiPc, CuPc, and the monomeric α‐modification of PtPe. In the valence bands contributions from d‐like central metal orbitals can be distinguished from the mo…
Abstract Micas are described from the kaolin type Tertiary weathering crusts formed on granites and gneisses of Lower Silesia, Poland. In the weathering crust, large scale processes of transformation of micas (muscovite, biotite) take place. Weathering of micas is a gradual transformation of their structures by remova…
Biomedical engineering, involving the application of engineering knowledge, expertise, and techniques to medicine and surgery, is a subjcct that tends to attract engineers and physical scientists because of the attitude that here one may apply technology to the improvement of life righ t at its source, within or about…
Abstract The electronic structure of the valence band of crystalline (α and γ) and amorphous Al 2 O 3 is measured by X‐ray photoemission. No significant changes are found in the different crystalline forms. A broad band observed at about 4 eV below the valence band is associated with the 2s states of the oxygen atoms,…
A study of the redox potentials of a range of metal phthalocyanines in non-aqueous media compared with analogous data for some porphyrin complexes provides evidence for extensive back donation in metallophthalocyanines. The potentials for some couples are exceedingly sensitive to axial ligation. It is suggested that t…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTOrbital interaction in three systemsSatoshi Inagaki, Hiroshi Fujimoto, and Kenichi FukuiCite this: J. Am. Chem. Soc. 1976, 98, 16, 4693–4701Publication Date (Print):August 1, 1976Publication History Published online1 May 2002Published inissue 1 August 1976https://pubs.acs.or…
1. The effects of calcium on the motility of different preparations of flagella from Crithidia oncopelti were studied using stroboscopic and high-speed cine photographic techniques. 2. By varying the concentration of calcium in suspensions of chemically treated samples of the organism it was found that changes occurre…
The surface of Monel‐400 alloy was exposed to high p H, aqueous corrosion at 285°C, under both oxidizing and reducing conditions. After exposures lasting from 0.3 to 335 hr the surfaces were examined by x‐ray photoelectron spectroscopy, scanning electron microscopy, and other techniques. Under reducing conditions, no…
Culture medium of exponentially growing Bordetella pertussis (strain 114) contains significant quantities of soluble (100,000 X g for 1 h) adenylate cyclase. The enzyme was purified by chromatography on diethylaminoethyl-cellulose and Sephadex G-200. The purest material yielded a single band on sodium dodecyl sulfate-…
Abstract Pit initiation at passive iron in borate and phthalate buffer solutions was investigated by separately measuring dissolution rates of Fe(III) and Fe(II) at rotating ring‐dis electrodes. The rate of Fe(III) dissolution grow linearly with the chloride concentration. Fe(II) appears simultaneously with the first…
Using the neutron scattering technique, we have measured the temperature dependences of the characteristic correlation lengths in semidilute polymer solutions in the vicinity of the theta (Θ) point. From the analysis of the data in the Guinier range, with a sample containing a few labeled chains, we find that the radi…
The equation is derived which describes the dynamics of the phase of the charge density wave in the Peierls-Fröhlich state in the presence of the impurity scattering. By use of the correlation function of the phase, the frequency dependence of the electrical conductivity, σ(ω), is calculated at T =0 K for the case of…
The influence of ferrocene on the flammability and smoke generation behavior and thermal characteristics of poly(vinyl chloride) (PVC) and poly(vinyl alcohol) (PVC) was examined in order to understand the basis of ferrocene's activity as a flame-retardant and smoke-suppressant additive. Ferrocene increased char format…