Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Analytical Chemistry and Spectroscopy  (48)
  • General Chemistry  (42)
  • 1
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 15 (1988), S. 193-204 
    ISSN: 0887-6134
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A method which involves the use of tandem mass spectrometry (MS/MS) for the identification of drug metabolites has been demonstrated with a triple quadrupole mass spectrometer. The method is based on the fact that metabolites usually retain various substructures of the original drug molecule. MS/MS is capable of rapidly identifying molecules with characteristic substructures without prior separation. It is shown that this method makes it possible to postulate possible drug metabolite structures rapidly and systematically without the use of standards. The MS/MS method, as it was applied to the identification of the metabolites of a new antiepileptic drug, zonisamide, is discussed. In this case it was possible to identify isomeric metabolites due to their differences in vaporization times off the probe and their different daughter spectra. The complementary uses of the neutral loss and parent scans for the determination of the site of metabolism is demonstrated. A new figure of merit, the limit of identification, is introduced. The amount of the epoxide metabolite of carbamazepine necessary for its reliable identification in urine was shown to be 0.4 ng/μl. The application of various techniques to confirm preliminary findings with this MS/MS method are described.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Journal of High Resolution Chromatography 16 (1993), S. 52-52 
    ISSN: 0935-6304
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Journal of High Resolution Chromatography 22 (1999), S. 29-32 
    ISSN: 0935-6304
    Keywords: Capillary electrochromatography ; electroosmotic flow ; frit ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The formation of bubbles in capillary electrochromatography (CEC) is well documented: possible origins include Joule heating and variations in EOF velocity on passing from the stationary phase through the frit and into the open tube. Methods for the prevention of bubble formation are discussed which are confirmed by experimental results. Using frit lengths varying from 1 mm to 6 mm it is shown how frit length is directly related to the likelihood of bubble formation and how this is affected by applied voltage. It is shown that the change in applied voltage across a capillary affects the formation of bubbles and also that rebonding octadecylsilane (ODS) onto the silica frit after formation of the frit can minimize the formation of bubbles and how this effects the chromatography. A method is also described for increasing the robustness of silica capillaries using a column coupler along with modifications made to conventional capillary electrophoresis equipment to cater for CEC.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Journal of High Resolution Chromatography 15 (1992), S. 478-479 
    ISSN: 0935-6304
    Keywords: Gas chromatography ; Kováts retention index ; GW-BASIC program ; Computer-assisted calculation ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Journal of High Resolution Chromatography 7 (1984), S. 144-146 
    ISSN: 0935-6304
    Keywords: Gas chromatography ; Capillary column ; Cyclopentolate ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für die chemische Industrie 74 (1962), S. 60-68 
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die kernmagnetische Resonanz des 31P-Kerns läßt sich für die Strukturaufklärung von Phosphor-Verbindungen sowie für analytische und kinetische Untersuchungen verwenden. Es wird ein Überblick über die bisher bestimmten 31P-Resonanzen gegeben.
    Additional Material: 6 Tab.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 29 (1994), S. 329-332 
    ISSN: 0030-493X
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 2 (1988), S. 275-276 
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 3 (1989), S. 293-294 
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The ion PhSiH2- undergoes a number of fragmentations upon collisional activation, including losses of H·, H2 (mainly to form PhSi-), and SiH2, together with formation of HSi-. The ion/molecule chemistry of PhSiH2- is characteristic of silyl anion systems and bears no analogy to that of benzyl anion reactions; for example with N2O and CO2 it forms Ph(H)2SiO- as the sole ionic product, while with CS2 it yields Ph(H)2SiS-.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 6 (1992), S. 573-578 
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Effects from higher order non-linear resonances, ‘black canyons’, have been observed for ions stored within the quadrupole ion-trap mass spectrometer. At specific qz values, higher-order field effects were observed to cause decreased intensity of chemical ionization (CI) reagent ions, due to ineffcient storage, as well as collision-induced dissociation. Efects have been observed, whether or not the CI reagent ions are mass-selected, and exibit increased severity with longer storage times. Previous reports have shown ‘black holes’ due to inefficient storage of product ions in tandem (MS/MS) spectra, but have reported no such effects in normal mass spectra. Without employing resonant excitation, higher-order field effects were investigated and found to occur continuously along iso-βz lines for βz = 1/3, 1/2, and 2/3. Described in this paper are the directs from higher-order fields on ions stored at specific az values, and indirec effects by those ions. Also described in this paper is new evidence for ‘black canyons’ occurring at βz = 1/3 at negative az values.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...