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21.
New HPLC Method to Determine Ethyl Carbamate in Alcoholic Beverages Using Fluorescence Detection 总被引:2,自引:0,他引:2
ABSTRACT: A new methodology to the quantification of ethyl carbamate (EC) has been developed. This method allows the analysis by HPLC of ethyl carbamate in samples of wine, fortified wine, and wine brandy, by a pre-column derivatization with 9-xanthydrol, and fluorescence detection. This does not require previous sample extraction or concentration. The method presents an average recovery of 96% among samples studied, a detection limit of 4.2μg/L, and an average intermediate precision of 6.3%. The comparison of the results obtained for EC analysis on the same wine brandy samples by GC/MS and HPLC are statistically indistinguishable with 97.5% probability. The results of the analysis of 42 samples are presented. 相似文献
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Lilli Heinrich und Werner Baltes 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1987,185(5):362-365
Zusammenfassung In zwei unterschiedlich gerösteten Robustakaffees und vier handelsüblichen Röstkaffees wurden die Phenole in bezug auf Struktur und Quantität untersucht. Nach speziellen Extraktions- und Reinigungsverfahren erfolgte die Identifizierung und Quantifizierung nach gaschromatographischer Trennung der Trimethylsilylether mit Hilfe der GC-MS-Kopplung. Die Gehalte der 35 identifizierten Phenole lagen in einem Bereich von unter 0,1 bis über 1000 mg/kg. 16 Phenole wurden erstmals im Kaffee nachgewiesen.
Herrn Dr. H. Lange zum 60. Geburtstag gewidmet 相似文献
Determination of phenols in coffee
Summary The structure and quantity of phenols, occurring in two different roastedRobusta coffees and in four samples of roast coffee, were investigated. Identification and quantification were carried out after special extraction procedures and clean-up methods by gas chromatography/mass spectrometry. The quantities of 35 phenols investigated ranged from below 0.1 mg/kg to more than 1000 mg/kg. Sixteen phenols were identified in coffee for the first time.
Herrn Dr. H. Lange zum 60. Geburtstag gewidmet 相似文献
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Reviews the book, Counseling and psychotherapy of work dysfunctions by Rodney L. Lowman (see record 1993-98413-000). Dr. Lowman's book on work dysfunctions serves as a seminal product for further understanding a much-neglected component of the lives of the many men and women who seek psychological assistance in working through issues around their employment. The book conveys in a well-written, sometimes humorous, style that "work is a natural part of living, and the issues it raises are important parts of character." The overall impression is that of a well-thought-out and most readable book. There is no doubt in this reviewer's mind that it will become essential reading for psychologists, social workers, family therapists, and graduate students who are becoming increasingly involved in this field of study. What this reviewer found very helpful was the clarity of presentation of the assessment techniques as well as the amply illustrated intervention modules that may be utilized. To this reviewer, there is no doubt that this is one area for psychologists' contributions in the future--the work area. Lowman's book gives us basic material from which to continue to build our profession in a new and exciting direction. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
26.
The mechanism of neurite penetration of three-dimensional fibrin matrices was investigated by culturing embryonic chick dorsal root ganglia (DRGs) within fibrin gels, upon fibrin gels, and upon laminin. The length of neurites within three-dimensional matrices of fibrin was decreased in a concentration-dependent manner by agents that inhibited plasmin, e.g. aprotinin, or that inhibited plasminogen activation, e.g., epsilon-aminocaproic acid (EACA), or plasminogen antiserum. In contrast, such agents increased the length of neurites growing out from DRGs cultured upon two-dimensional substrates of fibrin and had no effect on the length of neurites growing out from DRGs cultured upon laminin. Visualization of neurites within three-dimensional fibrin matrices demonstrated that the distance between fibrin strands was much smaller than the diameter of neurites. All these data were consistent with the hypothesis that fibrinolysis localized to the region of the neurite tip is an important mechanism for neurite penetration of a physical barrier of fibrin strands arranged in a three-dimensional matrix. 相似文献
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Droplet formation on Si surfaces bombarded by 10 keV beams from a liquid metal indium ion source has been observed. It has been verified that excess indium is transported in the ion beam, probably in the form of charged droplets. SIMS, SEM and RBS techniques have been used to study the distribution of droplets at the surface. At the specified ion source operating conditions, equilibrium droplet coverage is of the order of 25%. Individual droplets have an average diameter of 0.35 ωm and an average height of 2.2 nm. At a bombardment current density of 0.1 mA cm?2, equilibrium coverage is reached in about 1 s. 相似文献
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Nicotin und Ioan D. Vldescu 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1938,75(5):450-457
Ohne Zusammenfassung 相似文献