ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
Filter
  • Analytical Chemistry and Spectroscopy  (86)
Sammlung
Schlagwörter
Verlag/Herausgeber
Erscheinungszeitraum
  • 1
    Digitale Medien
    Digitale Medien
    On-line coupled HPLC-HRGC: A powerful tool for vapor phase FTIR analysis (LC-GC-FTIR) (1991)
    Weinheim : Wiley-Blackwell
    Journal of High Resolution Chromatography 14 (1991), S. 160-163 
    Details
    ISSN: 0935-6304
    Schlagwort(e): Coupled HPLC-HRGC ; Furanocoumarins ; LC-GC ; LC-GC-FTIR ; Chemistry ; Analytical Chemistry and Spectroscopy
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The design of an on-line LC-GC-FTIR system using an on-column interface and partially concurrent solvent evaporation with early vapor exit is described. The integration of LC-GC coupling into vapor phase FTIR analysis enables problems of sensitivity encountered with HRGC-FTIR detection to be over-come. The applicability of the method is demonstrated by the identification and determination of citropten and bergapten in bergamot oil.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jhrc.1240140304
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 2
    Digitale Medien
    Digitale Medien
    Notiz zur protonenkatalysierten Gasphasencyclisierung von N-Benzoyl-α-aminosäremethylesternXXVIII. Mitteilung ‘Massenspektrometrische Untersuchung organischer Stickstoffverbindungen’; als XXVII. Mitteilung gilt: H. Schwarz, R. Sezi, K. Levsen, H. Heimbach und F. Borchers, Org. Mass Spectrom., im Druck. (1977)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 12 (1977), S. 477-478 
    Details
    ISSN: 0030-493X
    Schlagwort(e): Chemistry ; Analytical Chemistry and Spectroscopy
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Beschreibung / Inhaltsverzeichnis: Chemical ionization mass spectrometry of the title compounds demonstrates that the formation of the [M+H—CH3OH]+ ions is strongly influenced by the degree as well as the type of alkyl substitution of the α-carbon atom. The extent of cyclization (i.e. formation of [M+H—CH3OH]+) closely resembles that of the activated esters in condensed phases.
    Notizen: Art und Anzahl der Alkylsubstituenten am α-C-Atom der Titelverbindungen beeinflußen in entscheidender Weise die durch chemische Ionisation induzierte Methanol-Eliminierung aus den [M + H]+-Ionen. Die Cyclisierungstendenz entspricht sehr stark der von aktivierten Estern in kondensierter Phase.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/oms.1210120716
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 3
    Digitale Medien
    Digitale Medien
    Combined thin-layer chromatography/mass spectrometry without substance elution: Use for direct identification of amino acids as dansylated esters (1987)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 14 (1987), S. 1-4 
    Details
    ISSN: 0887-6134
    Schlagwort(e): Chemistry ; Analytical Chemistry and Spectroscopy
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Amino acids can be identified unambiguously in form of their dansylated methyl esters by combination of thin-layer chromatography on polyamide and subsequent mass spectrometry without prior substance elution from the chromatographic polyamide carrier. The evaporation intensity of the amino acid derivatives is sufficient to get excellent mass spectra with significant structural information also with very small amounts of starting material (picomole level), which guarantee a high separation power in the TLC step. Besides the methylester derivatives, in part, products additionally methyl substituted at the sulfonamide nitrogen could be separated.
    Zusätzliches Material: 1 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/bms.1200140103
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 4
    Digitale Medien
    Digitale Medien
    Combined thin-layer chromatography/mass spectrometry without substance elution: Application to the rapid analysis of dipeptide mixtures (1987)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 14 (1987), S. 5-7 
    Details
    ISSN: 0887-6134
    Schlagwort(e): Chemistry ; Analytical Chemistry and Spectroscopy
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The simple combination of thin-layer chromatography on polyamide with subsequent mass spectrometry of the separated compounds together with the carrier material has been employed for unambiguous identification of individual dipeptides in a mixture. The dipeptides were analysed in the form of their dansyl methyl ester derivatives. The appearance of molecular ions in the electron impact mass spectra simultaneously with the ions dans-NH=CHR⌝+ indicating the corresponding N-terminal amino acid residue enables a rapid and sensitive structure elucidation of the dipeptides. The chromatography and mass spectrometry can be performed with 0.2-0.3 nmol dipeptide.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/bms.1200140104
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 5
    Digitale Medien
    Digitale Medien
    Fragmentation of deuteromethanol from 3,3′,4,4′-[2H4]-prostanoid pentafluorobenzylester/methoxime/trimethylsilylether derivatives by collisionally activated decomposition (1989)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 18 (1989), S. 937-938 
    Details
    ISSN: 0887-6134
    Schlagwort(e): Chemistry ; Analytical Chemistry and Spectroscopy
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: In negative ion chemical ionization mass spectra of prostanoid pentafluorobenzylester(PFB)/methoxime(MO)/ trimethylsilylether(TMS) derivatives [M-PFB]- is the most abundant fragment ion. Collisionally activated decomposition (CAD) spectra of this ions show nearly only fragmentation of trimethylsilanol (TMSOH), (CH3)2Si=CH2, carbon dioxide and methanol. CAD spectra of [M-PFB]- ions of 3,3′,4,4′-deuterated PGE2 and 6-oxo-PGF1α PFB/MO/TMS derivatives fragmentation of methanol and deuteromethanol (CH3OD) is observed. The ratio of CH3OH/CH3OD is about 3:1 (PGE2) and 9:1 (6-oxo-PGF1α) respectively. This loss of deuterium in the internal standard needs to be considered when employing the isotope dilution technique in quantitative prostanoid analysis and tandem mass spectrometry.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/bms.1200181015
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 6
    Digitale Medien
    Digitale Medien
    Preparation and mass spectral characterization of pentafluorobenzyl derivatives of alkyl and hydroxyalkyl-nucleobase DNA adducts (1989)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 18 (1989), S. 958-972 
    Details
    ISSN: 0887-6134
    Schlagwort(e): Chemistry ; Analytical Chemistry and Spectroscopy
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Pentafluorobenzyl (PFBz) derivatives of the following nucleobases were prepared: cytosine, 5-methylcytosine, O2-methylcytosine, O2-ethylthymine, O4-ethylthymine, 5-hydroxymethyluracil, N6-methyladenine, O6-methylguanine, O6-hydroxyethylguanine and O6-hydroxyethylpurine. 13C nuclear magnetic resonance was diagnostic for O- versus N-attachment of the PFBz moiety: the resonance of the methylene carbon appeared in the range 29.15-42.13 ppm for NCH2C6F5, and 58.45-69.01 for OCH2C6F5. Considerable structural information was provided by mass spectrometry with ionization by electron impact. All of the derivatives were detected with high sensitivity and specificity by gas chromatography with detection by electron capture negative ion mass spectrometry, reflecting not only their chemical and physical stability, but also their strong tendency to form a structurally diagnostic anion, [M - PFBz]-, in high yield under these ionization conditions. PFBz derivatives are therefore attractive forms of alkyl-substituted nucleobases for analysis by mass spectrometry.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/bms.1200181103
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 7
    Digitale Medien
    Digitale Medien
    Fast identification of mycobacterium species by GC analysis with trimethylsulfonium hydroxide (TMSH) for transesterification (1993)
    Weinheim : Wiley-Blackwell
    Journal of High Resolution Chromatography 16 (1993), S. 161-165 
    Details
    ISSN: 0935-6304
    Schlagwort(e): Capillary GC ; Mycobacterium ; Single colony ; Trimethylsulfonium hydroxide (TMSH) ; Fatty acid methyl esters (FAMEs) ; Mycolic acid cleavage products (MACPs) ; Secondary alcohols ; Chemistry ; Analytical Chemistry and Spectroscopy
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Trimethylsulfonium hydroxide (TMSH) reproducibly converts fatty acids bound in, e.g., biomolecules such as phospholipids and/or glycerides, into the corresponding fatty acid methyl esters (FAMEs). The transesterification can be performed at room temperature in a fast single step reaction. Surprisingly, secondary alcohols and mycolic acid cleavage products (MACPs) are also released from mycobacteria under these conditions.The complex reaction mixtures containing FAMEs, MACPs, and secondary alcohols can easily be separated by high resolution temperature-programmed capillary GC. Different species of mycobacteria give rise to characteristic chromatographic patterns and the amount of lipids from a single colony of mycobacteria is sufficient for reliable identification of the bacteria. The profiles of the chromatograms match well those obtained from other sample preparation techniques.The TMSH method of identification of mycobacteria from the patterns of the gas chromatograms is faster and more sensitive than conventional methods, which also involve transesterification. The identification of mycobacterial species by microbiological culture techniques is difficult to perform and requires several weeks.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jhrc.1240160306
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 8
    Digitale Medien
    Digitale Medien
    Enantiomeric separation of acidic drugs by capillary electrophoresis using a combination of charged and uncharged β-cyclodextrins as chiral selectors (1996)
    Weinheim : Wiley-Blackwell
    Journal of High Resolution Chromatography 19 (1996), S. 669-673 
    Details
    ISSN: 0935-6304
    Schlagwort(e): Capillary electrophoresis ; Enantiomeric separations ; Acidic compounds ; Neutral β-cyclodextrins ; Sulfobutyl ether β-cyclodextrin ; Chemistry ; Analytical Chemistry and Spectroscopy
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: High resolution could be achieved for the enantiomers of acidic drugs, namely, sulindac, fenoprofen, ketoprofen, warfarin, and hexobarbital, in a buffer of pH 3 by the simultaneous addition of uncharged and charged β-cyclodextrin derivatives. The interaction of the analytes with the anionic sulfobutyl ether β-cyclodextrin provides the analytes with an adequate electrophoretic mobility whereas the interaction with various neutral β-cyclodextrins generates high enantioselectivity. Five neutral cyclodextrins, the native β-cyclodextrin, as well as methyl-, dimethyl-, trimethyl- and hydroxypropyl-β-cyclodextrin, were tested to enhance the enantioselectivity of the electrophoretic system. High resolution values and the shortest analysis times for the five drugs tested were achieved in a buffer made of 100 mM phosphoric acid adjusted to pH 3 with triethanolamine and containing dimethyl- or trimethyl-β-cyclodextrin in addition to sulfobutyl ether β-cyclodextrin.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jhrc.1240191203
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 9
    Digitale Medien
    Digitale Medien
    Molecular modelling experiments on chiral recognition in GC with specially derivatized cyclodextrins as selectors (1993)
    Weinheim : Wiley-Blackwell
    Journal of High Resolution Chromatography 16 (1993), S. 299-311 
    Details
    ISSN: 0935-6304
    Schlagwort(e): Capillary gas chromatography ; Derivatized cyclodextrins ; Molecular modelling ; Chiral recognition ; Chemistry ; Analytical Chemistry and Spectroscopy
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The results of gas chromatographic enantiomeric separations of selected non-polar and polar test solutes (limonene and 1-phenylethanol) using two different derivatives of β-cyclodextrin, permethyl-β-CD and 2,3-dimethyl-tert-butyldimethylsilyl-β-CD (PMCD and TBCD) are interpreted in combination with the conclusions from molecular modelling calculations based on docking experiments. A comparison of the two selectors which were used as solution in a polysiloxane matrix (OV 1701) indicated that the less flexible TBCD which is blocked on one side by the bulky tert-butyldimethylsilyl groups seems to possess advantages for certain chiral separations, especially of the non-polar type. The special properties of TBCD as selector are also demonstrated by chiral separations of other compounds.
    Zusätzliches Material: 10 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jhrc.1240160507
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 10
    Digitale Medien
    Digitale Medien
    A water trap for static cryo-headspace gas chromatography (1996)
    Weinheim : Wiley-Blackwell
    Journal of High Resolution Chromatography 19 (1996), S. 37-42 
    Details
    ISSN: 0935-6304
    Schlagwort(e): Chemistry ; Analytical Chemistry and Spectroscopy
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The headspace gas in static headspace gas chromatography contains mostly saturated water vapor. In the case of the cryofocusing enrichment technique this may cause baseline distortion in the early part of the chromatogram or may even lead to ice-plugging of the capillary column. A water-trap is described in which the water vapor is removed from the headspace gas before entering the cryo-trap. The water trap is packed with lithium chloride on a porous support and is regenerated after each analysis by heating under backflush conditions. It therefore can be used for automatic operation. Data are given for the precision and accuracy, and some practical examples, for environmental and flavor analysis are shown.
    Zusätzliches Material: 6 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jhrc.1240190107
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...