Absorbance(a.Intensity(a.u.)

正the XAS is a bulk characterization rather than a sur‐face‐sensitive tool. The penetration depth is a function of X‐ray attenuation coefficient of the material at the relevant incident X‐ray energy, it is about 5–10 mm when measuring the LIII edge of Ce at around 6 keV [51,52]. Recently, Schmitt et al. [20] re‐viewed the XAS study on the defect structure and chemistry in ceria and its solution. Herein, we just survey this tool used for characterization of reduced ceria powder as a catalyst.In a partially reduced ceria, the XANES part of X‐ray absorp‐tion spectrum for the Ce LIII edge can be used to quantify Ce3+and Ce4+ valence states to study the effect of particle size, do‐     

Tert.-Butylperoxyacetat (I), tert.-Butylperoxybenzoat (II) und Laurylperoxid (III), auch in Gegenwart von tert.-Butylhydroxyperoxid (IV)

Ohne Zusammenfassung     

Schwefelbestimmungsapparat (D. R. G. M.)

Ohne Zusammenfassung(Mit Abbildung.)     

Inorganic coordination polymers. XII. Chromium(III) tris(phosphinates)

Cohesive films of a series of chromium(III) tris(phosphinates)[Cr(OPRR′O)(OPR″-R?O)(OPR^*R^**O)]_y in which the side groups on the phosphorus are alkyl, phenyl, and/or hydrogen groups have been prepared by reaction casting or by hot pressing. The preparative reaction appears to involve conversion of an aquahydroxo or hydroxo chromium(III) bis(phosphinate) to an intermediate hydroxo bis(phosphinate) containing coordinated phosphinic acid followed by an intrachain reaction leading to the tris(phosphinate). Tensile strengths of the chromium(III) tris(phosphinates) range from 100 to 5600 psi, elongations from less than 1 to 100%. Thermogravimetric data indicate that major decomposition occurs at temperatures from 200 to 435°C in air and from 410 to 510°C in nitrogen. Infrared spectra and physical properties are interpreted to support a structure for the chromium(III) tris(phosphinates) which is based on linear, triple-bridged chains. The presence of octyl or other long alkyl side groups on the phosphorus improves the physical properties, presumably by internal plasticization, but leads to decreased thermal stability.     

Hetarylcyanamides. (Review)

The nomenclature and the synthesis of hetarylcyanamides and their reactions that take place at the cyanoamino group are discussed.     

Heterocalixarenes. (Review)

Heterocalixarenes, i.e. heterocycle-based calixarenes, are interesting as receptors of a variety of molecules and ions. These compounds are described with regard to their syntheses, reactivity, and inclusion properties. In the presentation of benzoxazine-based calixarenes attention is paid to their chirality.     

Pyrylocyanines. 16. Tetraphenyl-substituted (2-pyrylo) (4-pyrylo) cyanines

Unsymmetrical tetraphenyl-substituted (2-pyrylo) (4-pyrylo) monomethylidyne-, carbo-, and dicarbocyanines and their thiopyrylium and pyridinium analogs were synthesized. The absorption spectra of these dyes were studied. The spectral characteristics of their long-wave absorption bands have values that are intermediate between the analogous characteristics of the corresponding symmetrical isomers of the and series.See [1] for communication 15.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1178–1183, September, 1982.     

Organosilane polymers. II. Poly(ethylmethyl-co-dimethylsilylene) and poly(methylpropyl-co-dimethylsilylene)

Polydimethylsilylene is a largely crystalline, high-melting polymer that is soluble only above 200°C and does not thermoform below its decomposition temperature. Introduction of ethyl and propyl substituents into the linear silylene system by random copolymerization of dimethylsilylene with ethylmethyl- and methylpropylsilylenes leads to tractable polymers that are soluble in common solvents at normal ambient temperatures.     

Pfropf-Copolymere: (Poly(alkylmethacrylat-gäthylenoxid). 2. Mitt. Kristallisation

Ohne Zusammenfassung     

Pfropf-Copolymere: (Poly(alkylmethacrylat-g?thylenoxid). 2. Mitt. Kristallisation

Ohne Zusammenfassung     

Cavitands. (Review)

The syntheses, reactivity and complexing properties of cavitands are reviewed.     

Diazapyrenes. (Review)

Published data on methods for the synthesis of isomeric diazapyrenes and their properties are reviewed.     

Pyrroloquinolines. (Review)

Methods for the synthesis of six types of pyrroloquinolines with various types of ring fusion and their chemical properties are reviewed.