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1.
2.
J. Prinz M. Sajatovic M. Konrad A. Kröpfl J. Hartenberger Ch. Steger 《e & i Elektrotechnik und Informationstechnik》2003,120(2):a16-a19
6. Zusammenfassung In diesem Artikel wurde die Data in Voice-Technologie vorgestellt. DiV ist eine Methode, die es erlaubt, kurze Daten-Messages
gemeinsam mit der Sprache im analogen Flugfunkkanal zu übertragen. Man ist bei FREQUENTIS überzeugt, dass man mit dieser Methode
viele Nachteile des vorhandenen analogen Flugfunks beseitigen und dadurch die Flugsicherheit wesentlich erh?hen k?nnte. 相似文献
3.
Maurus Biedermann Konrad Grob Dieter Fr?hlich Werner Meier 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1992,195(5):409-416
Summary On-line coupled liquid chromatography-gas chromatography-flame ionisation detection (LC-GC-FID) enables efficient and unambiguous determination of irradiation for some fat-containing foods (e.g. meat). Other products, however, contain interfering components or are contaminated, e.g., with mineral oil. Since more selective detection by mass spectrometry has limited success, the determination was improved by a more selective isolation of some key components among the fat degradation products, e.g. the dienes or trienes, by LC-LC-GC-FID. Applications are shown for soup mixes, some spices, fish, and shrimps.
Nachweis der Bestrahlung fetthaltiger Lebensmittel durch direkt gekoppelte LC-GC und LC-LC-GC
Zusammenfassung Die Bestrahlung einiger fetthaltiger Lebensmittel, z. B. Fleisch, kann mit direkt gekoppelter LC-GC-FID rationell und eindeutig nachgewiesen werden. In anderen Proben wird die Analyse aber durch Inhaltsstoffe des Produktes oder durch Verunreinigungen (z. B. mit Mineralöl) gestört. Da selektivere Detektion durch Massenspektrqmetrie wenig verspricht, wurde der Nachweis durch selektivere Isolierung von Schlüsselkomponenten unter den Bestrahlungsprodukten, z. B. der Diene oder Triene, mittels LC-LC-GC yerbessert. Anwendungen werden gezeigt für Suppenpulver, einige Gewürze, Fisch und Garnelen.相似文献
4.
Peter Mertens Christian Stary Konrad Walser Thomas Deelmann Franz Lehner Sebastian Günther Christian Scheer 《WIRTSCHAFTSINFORMATIK》2006,48(4):288-295
Ohne Zusammenfassung 相似文献
5.
Anna Artho Konrad Grob Carlo Mariani 《European Journal of Lipid Science and Technology》1993,95(5):176-180
The previous on-line LC-GC method for the direct analysis of the minor components in oils and fats (without cleavage of esters) was modified: The free alcohols/sterols were silylated instead of acylated, and the LC fraction transferred to GC is widened to range from the beginning of the LC chromatogram up to the sterol esters. Silylation eliminated the problem that acylation may esterify some free alcohols with free fatty acids from the oil if the oil or fat is of high acidity. Widening of the LC fraction to include squalene and the tocopherols added information to that previously obtained. 相似文献
6.
On the Spreading of Lipids on the Skin The spontaneous spreading of liquid lipids on human skin is an important property for the use value of such products in cosmetic and pharmaceutical preparations. A comparative evaluation procedure based on an impression method is described, by means of which it is possible to determine the spreading rates in a reproducible manner. The standardized spreading values of a number of lipids are discussed in comparison with their chemical structure and physico-chemical data such as viscosity and surface tension. None of these data series correlates entirely with the spreading rates of all the lipids tested. However, it is possible to assess relative spreading rates within similarly structured groups of compounds. 相似文献
7.
V. Spitzer F. Marx J. G. Maia K. Pfeilsticker 《European Journal of Lipid Science and Technology》1991,93(5):169-174
Four acetylenic fatty acids [11-octadecen-9-ynoic acid (E) (ximenynic acid), 11-octadecen-9-ynoic acid (Z), 9,11-octadecadiynoic acid and 13-octadecen-9,11-diynoic acid (E) (exocarpic acid)] were found in the seed oil of Curupira tefeensis (Olacaceae) as minor compounds. The mass spectra of the methyl esters (EI and CI mode), picolinyl esters and 4,4-dimethyloxazoline derivatives of these acids are discussed in detail. Furthermore the NMR data of 9,11-octadecadiynoic acid and 13-octadecen-9,11-diynoic acid are presented. 相似文献
8.
V. Spitzer F. Marx K. Pfeilsticker J. G. S. Maia 《European Journal of Lipid Science and Technology》1994,96(10):395-396
The mass spectra of the picolinyl derivatives of two natural occurring cyclopropenoid fatty acids (malvalic and sterculic acid) showed, besides the typical peaks for picolinyl derivatives, a characteristic gap of 66 amu between the two allylic positions of the ring system. This phenomenon could be used for the determination of the ring position of this type of fatty acids. 相似文献
9.
Anna Puig-Molina Lars Pleth Nielsen Alfons M. Molenbroek Konrad Herbst 《Catalysis Letters》2004,92(1-2):29-34
The chemical state of arsenic deposited on a NiMoP/Al2O3 hydrotreating catalyst exposed to ppb levels of arsenic over several years in a refinery reactor has been studied by in situ EXAFS. In the as-received As-NiMoP catalyst, arsenic is exclusively coordinated to oxygen atoms. Upon sulfiding the sample in 2%H2S/2%H2/96%He, the As atoms become surrounded by approximately two sulfur atoms. No evidence was found for Ni–As bond formation. A possible model for the As local environment is suggested on the basis of combined EXAFS results, STM data and FEFF8.0 simulations (program for ab initio calculations on multiple scattering XAFS and XANES). The FEFF8.0 simulations of the proposed model are in accord with the experimental data measured at the As K edge. In this model, an As atom is located at the edge of a hexagonally truncated Ni-MoS2 slab and is blocking the active NiMoS site. 相似文献
10.
In addition to the C21 steroid 15α-hydroxypregna-4,6-dien-3,20-dione, four 1- or 2-acylated polyunsaturated monoglycerides, 1- or 2-(cis-5,8,11,14-eicosatetraenoyl)-glycerol and 1- or 2-(cis-5,8,11,14,17-eicosapentaenoyl)glycerol were identified as constituents of the prothoracic defensive gland secretion of the
dytiscid beetle Agabus affinis by gas chromatography-mass spectrometry of trimethylsilylated gland extracts. In a feeding assay with minnows, synthetic
samples of the two 2-acylated monoglycerides showed only a weak activity as a feeding deterrent. For that reason, other possible
functions of the monoglycerides are discussed, such as roles as emulsifiers of cannabimimetics. 相似文献