ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
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
  • Articles  (12)
  • Analytical Chemistry and Spectroscopy  (11)
  • (1,1′-Ferrocenediyl)dimethylsilane  (1)
  • Wiley-Blackwell  (12)
  • 1
    Electronic Resource
    Electronic Resource
    Capillary gas chromatographic evaluation of trans-fatty acid content of food produced under the traditional conditions of semi-industrial frying (1996)
    Weinheim : Wiley-Blackwell
    Journal of High Resolution Chromatography 19 (1996), S. 180-182 
    Details
    ISSN: 0935-6304
    Keywords: trans-Fatty acids ; Semi-industrial frying ; Capillary GC ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jhrc.1240190313
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Determination of lactulose and mannitol in urine by HRGC (1995)
    Weinheim : Wiley-Blackwell
    Journal of High Resolution Chromatography 18 (1995), S. 692-694 
    Details
    ISSN: 0935-6304
    Keywords: Capillary gas chromatography ; Intestinal permeability ; Urine ; Sugars ; Lactulose ; Mannitol ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Alteration of intestinal permeability towards compounds like sugars is an indication of abnormalities observed in some diseases. Measurement of the dual sugar absorption of lactulose and mannitol is a non-invasive test of intestinal permeability. The use of this test is however limited by difficulties in the analysis of sugars in urine at low concentrations. In this study we have developed an analytical procedure for quantitative assay of the lactulose-mannitol pair in urine by high resolution gas chromatography. The minimum detectable amounts are 7.5 pg for lactulose and 4.4 pg for mannitol. The calibration curves are linear in the range of 100-6400 mg L-1. Recoveries are within the range 86-102 % for mannitol and 84-105 % for lactulose.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jhrc.1240181103
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Structural Studies of MCM-48 Derivatized with (1,1′-Ferrocenediyl)dimethylsilane (2000)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 2000 (2000), S. 97-102 
    Details
    ISSN: 1434-1948
    Keywords: Mesoporous materials ; MCM-48 ; Immobilization ; (1,1′-Ferrocenediyl)dimethylsilane ; 13C and 29Si solid-state NMR ; Sandwich-complexes ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The walls of the cubic mesoporous silicate MCM-48 have been grafted with ferrocenyl end groups by a ring-opening reaction of the ansa-bridged ferrocene [Fe{(η-C5H4)2SiMe2}], carried out in a pentane solution at room temperature. The orange product has been characterized by elemental analysis, powder X-ray diffraction, 13C and 29Si solid-state NMR, N2 adsorption measurements, and Fe K-edge EXAFS. A high loading has been obtained (8.18 mass % Fe) and, as a result of the inclusion of the organometallic moiety, the N2 adsorption isotherm exhibits a lower uptake. Direct structural evidence for the surface attachment of both single ferrocenyl and short chain oligo(ferrocenyl) fragments has been obtained.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
  • 4
    Electronic Resource
    Electronic Resource
    Mass spectrometric study of new α-methylene-γ-lactone carbohydrate derivatives (1988)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 16 (1988), S. 399-402 
    Details
    ISSN: 1052-9306
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A mass spectrometric study of six new α-methylene-γ-lactone carbohydrate derivatives has been carried out in order to correlate the occurrence of metastable transitions with the stereochemistry of the compounds. Results indicate that the decomposition of some metastable fragment ions usually releases higher amounts of kinetic energy when the chiral centre of the lactone ring has the (S) configuration. However, the kinetic energy released on the decomposition of metastable molecular ions seems to follow different trends as regards the configuration of the chiral centre of the lactone moiety, when one or two isopropylidene rings are present in the molecule. This study is being extended to some related compounds in order to confirm whether the kinetic energy release is preferentially affected in a particular way by the chirality.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bms.1200160178
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Gas-chromatographic headspace analysis of phenol and cresols in soils by direct acetylation (1996)
    Weinheim : Wiley-Blackwell
    Journal of High Resolution Chromatography 19 (1996), S. 207-212 
    Details
    ISSN: 0935-6304
    Keywords: Capillary gas chromatography ; Headspace ; Phenols ; Derivatization ; Soils ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A quick, simple and selective procedure has been developed for the determination of phenol, o-cresol, m-cresol, and p-cresol in soil samples. The method is based on the gas chromatographic headspace analysis of phenols as acetate derivatives. These acetates were prepared directly in the wetted soil samples by acetic anhydride in the presence of KHCO3· With this procedure sample handling is reduced to a minimum as desorption and derivatization of the analytes are developed from the wetted samples inside the vial of the head space sampler.The acetate esters were analyzed using a 60 m × 0.56 mm DIIDP capillary column (di-isodecyl-phthalate), using 2-chlorophenol as an internal standard. The detection limit was between 0.03-0.08 μg g-1 for the different species considered. Soil samples having carbon contents lower than 5 % can be analyzed by the proposed procedure.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jhrc.1240190406
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Mass spectrometric study of structure and stereochemistry of some stereoisomeric furanosidic derivatives (1992)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 27 (1992), S. 1114-1120 
    Details
    ISSN: 0030-493X
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A mass spectrometric study of eight new carbohydrate derivatives has been carried out to determine the influence of structure on the fragmentation mechanisms of stereoisomers. Results indicate that the relative intensities of peaks due to fragment ions of each pair of isomers are sometimes very different, especially those observed in the collision-induced decomposition mass spectra of [MH]+ ions. Metastable decompositions related to identical fragmentation processes of two isomers release different amounts of kinetic energy, however. It is usually observed that the kinetic energy released is larger for the S-configuration than for the R-configuration of the two epimers of a particular species.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/oms.1210271022
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Dissociation mechanisms of energy-selected chlorobutane ions: Experiment and theory (1993)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 28 (1993), S. 1229-1237 
    Details
    ISSN: 0030-493X
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The breakdown diagrams and photoionization efficiency curves of isomeric chlorobutane ions were obtained by energy-selected molecular ions with the photoelectron-photoion coincidence (PEPICO) technique. The loss of HCl from 1- and 2-chlorobutane molecular ions was found to be fast, and accurate dissociation onsets were determined from the crossover energy in the breakdown diagrams and appropriately corrected for the precursor thermal energy. In spit of the low activation energy, the isochlorobutane molecular ion was found to dissociate slowly near the dissociation limit, the time-of-flight distribution having been analyzed in terms of two exponential decay rates. The dissociation reaction involved a large kinetic energy release that pointed to a 1,2-elimination leading to a stable C4H8+· ion. AB initio calculations indicated that the reaction path involved an H-atom transfer through a barrier, which is a favorable case for a tunneling model to explain the slow decomposition rate. The kinetic energy release of chlorine radical loss from tert-chlorobutane was determined as a function of the ion internal energy. At low energies the kinetic energy release was nearly statistical but the dissociation from the excited electronic states resulted in a large and non-statistical kinetic energy release.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/oms.1210281039
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Spectroscopic properties of free phenolic 4-arylflavan-3-ols as models for natural condensed tannins (1993)
    Chichester : Wiley-Blackwell
    Organic Magnetic Resonance 31 (1993), S. 1057-1063 
    Details
    ISSN: 0749-1581
    Keywords: 4-Arylflavan-3-ols ; 1H NMR ; 13C NMR ; Circular dichroism ; Condensed tannins ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A unique range of free phenolic 4-arylflavan-3-ols consisting of four sets (3′,4′,5,7-tetrahydroxyflavan-3-ol or its 5-deoxy analogue coupled to phloroglucinol or resorcinol), each composed of three diastereomers (2,3-trans-3,4-trans, 2,3-trans-3,4-cis and 2,3-cis-3,4-trans) were synthesized to assess their spectroscopic properties. 1H and 13C NMR and circular dichroism data are related to selected structural and stereochemical features with a view to modelling natural phenolic oligoflavanoids.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrc.1260311206
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Conformational analysis of oligomeric flavanoids. 2For Part 1, see Ref. 8. - methyl ether acetate derivatives of profisetinidins (1995)
    Chichester : Wiley-Blackwell
    Organic Magnetic Resonance 33 (1995), S. 611-620 
    Details
    ISSN: 0749-1581
    Keywords: NMR ; 1H NMR ; condensed tannins ; profisetinidins ; stereochemistry ; conformation ; rotational isomers ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The profisetinidins are the most important polyflavanoids of commerce, making up the major constituents of wattle and quebracho tannins. Even within the dimeric profisetinidins, substantial complexity exists because of stereo-, regio-, rotational and conformational isomers. Definition of the stereochemistry of the upper and lower flavan units, the location of the interflavanoid bond, the conformation of the heterocyclic rings in the upper and lower flavan units and the conformations of major and minor rotational isomers in a series of methyl ether acetate derivatives of dimeric profisetinidin diastereomers is possible by application of COSY and NOE experiments. All compounds studied were present in two rotameric forms with the more compact conformation favored. The heterocyclic ring in the upper chain extender unit was predominantly in an E-conformation (i.e. half-chair in 2R,3S isomers and a ‘reverse’ half-chair in the 2S,3R isomers). The heterocyclic ring conformation of the terminal cate-chin unit, although mostly in an E-conformation, was often represented by significant proportions of A-conformers.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrc.1260330802
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Reorientational relaxation in liquid 1,4-dioxane as studied by Raman spectroscopy (1987)
    Chichester [u.a.] : Wiley-Blackwell
    Journal of Raman Spectroscopy 18 (1987), S. 457-460 
    Details
    ISSN: 0377-0486
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The anisotropic Raman spectra of liquid 1,4-dioxane have been recorded at several temperatures and at different concentrations of aqueous and carbon tetrachloride solutions. The rotational dynamics of the 1,4-dioxane molecules under these conditions is discussed in terms of appropriate correlation functions, reorientational relaxation times and second-order rotational spectral moments.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jrs.1250180702
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...