Untersuchungen an Stickstoff—Jod-Verbindungen. VII. Das IR-Spektrum des Stickstofftrijodid-1-Ammoniaks im Bereich der N–J-Grundschwingungen und Kraftkonstanten der N–J-Bindungen

Studies on nitrogen iodine compounds. VII. The IR spectrum of nitrogen triiodide-1 ammonia in the range of N—I fundamental vibrations and the valence force constants of the N—I bonds New infrared spectra in the region 33—600 cm^?1 of ¹⁴NI₃ · ¹⁴NH₃, ¹⁵NI₃ · ¹⁵NH₃ and ¹⁴NI₃ · pyridine, respectively, have been obtained. In addition, the infrared spectrum of ¹⁴NI₃ · ¹⁴ND₃, which has been prepared for the first time, was obtained. All absorption frequencies can be coordinated on the ground of the molecule model for the NI₃ scaffold with 5 atoms Z₂XY₂ of the symmetry C_2v which has been proved by X ray examination. A set of force constants has been calculated by approximation. The various nitrogeniodine valence force constants are discussed.     

Laser-induced incandescence for soot-particle sizing at elevated pressure

This paper describes the applicability of laser-induced incandescence (LII) as a measurement technique for primary soot particle sizes at elevated pressure. A high-pressure burner was constructed that provides stable, laminar, sooting, premixed ethylene/air flames at 1–10 bar. An LII model was set up that includes different heat-conduction sub-models and used an accommodation coefficient of 0.25 for all pressures studied. Based on this model experimental time-resolved LII signals recorded at different positions in the flame were evaluated with respect to the mean particle diameter of a log-normal particle-size distribution. The resulting primary particle sizes were compared to results from TEM images of soot samples that were collected thermophoretically from the high-pressure flame. The LII results are in good agreement with the mean primary particle sizes of a log-normal particle-size distribution obtained from the TEM-data for all pressures, if the LII signals are evaluated with the heat-conduction model of Fuchs combined with an aggregate sub-model that describes the reduced heat conduction of aggregated primary soot particles. The model, called LIISim, is available online via a web interface. PACS 65.80.+n; 78.20.Nv; 42.62.-b; 47.70.Pq     

Untersuchungen an Stickstoff-Chlor-Verbindungen. X. N-Perchlorylaziridin,N-Perchlorylazetidin und N-Adamantylperchlorsäureamid durch Aminolyse von Dichlorheptoxid

Studies on Nitrogen Chlorine Compounds. X. N-Perchlorylaziridine, N-Perchlorylazetidine, and N-Adamantylperchloric Acid Amide by Aminolysis of Dichlorine Heptoxide By aminolysis of dichlorine heptoxide with aziridine (ethyleneimine), azetidine (trimethyleneimine), and adamantylamine (tricyclo(3.3.1.1.^3,7)decane-1-amine) could be prepared three new N-perchloryl compounds. Furthermore several salts of N-adamantylperchloric acid amide were prepared. The compounds were characterized by i.r. and ¹H-n.m.r. spectroscopy and by analysis.     

Analysis of the band profiles of the enantiomers of phenylglycine in liquid chromatography on bonded teicoplanin columns using the stochastic theory of chromatography.

The retention behaviour of the enantiomers of underivatized phenylglycine was studied on a Chirobiotic T column packed with amphoteric glycopeptide teicoplanin covalently bonded to the surface of silica gel. The retention and the selectivity of separation of the enantiomers increase with rising concentration of ethanol or of methanol in aqueous-organic mobile phases. The band profiles of the less retained L-phenylglycine are symmetrical, but the band profiles of the more strongly retained D-phenylglycine are tailing in all mobile phases tested. The band broadening does not diminish even at very low concentrations of phenylglycine, so that it cannot be attributed to possible column overload. The analysis of the band profile using the stochastic theory of chromatography suggests that the broadening can be attributed to at least two additional chiral centres of adsorption in the stationary phase contributing to the retention of the more strongly retained enantiomer in addition to the adsorption of the less retained one. This behaviour can be explained by the complex structure of the teicoplanin chiral stationary phase.     

Phosphate und Arsenate

Ohne Zusammenfassung     

Molekulargewichtsbestimmung

Ohne Zusammenfassung