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
  • 1
    Electronic Resource
    Electronic Resource
    On the integration of kinetic models using a high-order taylor series method (1992)
    New York, NY : Wiley-Blackwell
    Journal of Chemometrics 6 (1992), S. 231-246 
    Details
    ISSN: 0886-9383
    Keywords: Integration methods ; Taylor series method ; Optimization methods ; Kinetic mechanisms ; Kinetic determinations ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A general equation to derive kinetic models up to any order is given. This equation greatly facilitates the application of the Taylor series method to the integration of kinetic models up to very high orders. When dealing with non-stiff models, computing time is always reduced by increasing the integration order, at least up to the 20th order. When the model is stiff, the integration order should be optimized; however, a twelfth order is recommended to integrate weakly stiff models. The use of an algorithm which permits the immediate calculation of the integration step size required to maintain a given accuracy leads to further reductions in computing time. When implemented as recommended here, a high-order Taylor series method is more rapid and accurate than Runge-Kutta and predictor-corrector methods and can be advantageously used in combination with optimization methods to perform mechanism studies and in multicomponent kinetic determinations.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cem.1180060503
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Improvement of enantioselective syntheses and chiral high resolution gas chromatographic analyses of (+)-2-allyl-2-carboethoxy-cyclopentanol (1997)
    New York, NY [u.a.] : Wiley-Blackwell
    Chirality 9 (1997), S. 321-324 
    Details
    ISSN: 0899-0042
    Keywords: Saccharomyces cerevisiae ; asymmetric β-keto-ester reduction ; enzymatic kinetic resolution ; chiral 2-allyl-2-carboethoxy-cyclopentanol ; chiral high resolution gas chromatography ; chiral stationary phase ; β-cyclodextrin derivative ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The improvement of the biocatalytic reduction of 2-allyl-carboethoxy-cyclopentanone (2) to the corresponding cyclopentanol derivative (+)-(1R,2R)-(1) was accomplished employing baker's yeast in organic media. This chiral cyclopentanol derivative (1), analyzed by high resolution gas chromatography performed over β-cyclodextrin stationary phase, was obtained in 38% yield (〉99% e.e.). Chirality 9:321-324, 1997. © 1997 Wiley-Liss, Inc.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
  • 3
    Electronic Resource
    Electronic Resource
    Capillary gas chromatography of amino acids as their tert-butyldimethylsilyl derivatives in the analysis of serum amino acids in metabolic diseases (1988)
    Weinheim : Wiley-Blackwell
    Journal of High Resolution Chromatography 11 (1988), S. 12-16 
    Details
    ISSN: 0935-6304
    Keywords: Gas chromatography, GC ; Capillary column ; Amino acids ; Derivatization ; Serum ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reaction of amino acids with N-methyl-N-(tert-butyldimethylsilyl)trifluoroaceamide (MTbSTFA) in acetonitrile affords good yields of amino acid derivatives with excellent gas chromatographic and mass spectrometric properties. The single-step derivatization procedure is highly reproducible. The TBDMS amino acids are stable at room temperature for at least three days. Only a single peak is observed for each amino acid. The procedure allows simultaneous analysis of asparagine and glutamine together with other serum amino acids. Separation is achieved on a borosilicate glass capillary coated with OV-1. The mass spectra of the TBDMS amino acids possess characteristic diagnostic ions. These properties were used in the sensitive detection by GC-MS and SIM-GC-MS of GABA and pipecolic acid in the serum of a newborn suspected of a Zellweger-type syndrome, which could not be detected by other methods.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jhrc.1240110105
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Application of HPLC for the detection of proteins in whey mixtures from different animal species (1991)
    Weinheim : Wiley-Blackwell
    Journal of High Resolution Chromatography 14 (1991), S. 289-291 
    Details
    ISSN: 0935-6304
    Keywords: HPLC ; Protein analysis ; Detection of whey mixtures ; 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
    URL: http://dx.doi.org/10.1002/jhrc.1240140421
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Molecular motions in poly(vinyl acetate) revisited. A thermally stimulated current study (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Polymer International 33 (1994), S. 293-302 
    Details
    ISSN: 0959-8103
    Keywords: dielectric relaxation ; dipolar relaxation ; thermally stimulated current ; thermally stimulated depolarisation current ; poly(vinyl acetate) ; amorphous polymer ; glass transition ; compensation effect ; liquid-liquid transition ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The dipolar relaxation mechanisms in poly(vinyl acetate) have been studied in detail using the technique of thermally stimulated currents. The papers published in the literature about this subject are very contradictory, particularly with respect to the assignment of the observed discharges to the corresponding motions at the molecular level. This work aims at clarifying these problems. We detected and characterised three different relaxation mechanisms: (1) a low temperature one (around -140°C) which was attributed to local internal rotations in the acetate side-groups; (2) a relaxation whose maximum occurs at 42°C, which corresponds to the glass transition relaxation, and shows a compensation behaviour; (3) an upper glass transition relaxation whose maximum appears at 87°C and was attributed to a liquid-liquid transition. These assignments have been made on the basis of the analysis of the behaviour of the samples when submitted to different thermal and electrical treatments.
    Additional Material: 16 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pi.1994.210330309
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Synthesis and characterization of epoxidized phenolic novolacs modified by furfuryl alcohol (1995)
    New York, NY [u.a.] : Wiley-Blackwell
    Polymer International 37 (1995), S. 21-26 
    Details
    ISSN: 0959-8103
    Keywords: epoxidation ; novolacs ; furan resins ; furfuryl alcohol ; epoxidized novolacs ; furfuryl alcohol-phenol reaction ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The possibility of reacting furfuryl alcohol with the p-position of phenolic rings, under acid conditions, was proved using different experimental techniques: size exclusion chromatography, Fourier transform infrared spectroscopy and 13C NMR. This reaction was then used in the modification of phenolic novolacs with furfuryl alcohol. After reaction with epichlorohydrin, epoxidized phenolic novolacs (EPN) modified with furan rings were obtained. They could be cured with aromatic diamines in a similar way to conventional EPNs. The presence of furan rings should improve burning resistance and smoke emission characteristics of the resulting networks.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pi.1995.210370102
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Coconut husk lignin. I. Extraction and characterization (1992)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 45 (1992), S. 633-644 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Recently lignin has been the object of a renewed interest because of the need to use raw materials from renewable resources. One such resource is coconut husk, a material usually discarded during the copra extraction process. Due to its high lignin content, coconut husk has been recognized as having a variety of applications. Therefore, it is important to know the approximate structure of coconut husk lignin and those variations introduced by different isolation methods. This work reports a general characterization of coconut husk lignin. Results are given of the contents of hydroxyl and noncondensed guaiacyl units, the extractability of the lignin in alkaline and “organosolv” media along with thermal properties of the extracted lignins. The extraction system of NaOH-anthraquinone at 150°C was most conveniently based on the relatively low amount of condensed lignin generated.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1992.070450410
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Coconut husk lignin. II. Characterization by infrared and nuclear magnetic resonance spectroscopy (1992)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 45 (1992), S. 645-653 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Results of the characterization of coconut husk lignin by infrared (IR) and proton nuclear magnetic resonance (H-NMR) spectroscopy are presented. Lignin was extracted with both alkaline and organosolv liquors. The IR spectra of dioxane lignin were very similar to those reported for hardwood lignins. Furthermore, these results combined with those obtained from the H-NMR studies suggest that coconut husk lignin can be classified into the Lm-type lignins. These lignins are characteristic of the monocotyledon class, of which the coconut palm is a member. The H-NMR studies showed that anthraquinone significantly inhibited the occurrence of lignin condensation during the alkaline extraction with sodium hydroxide solutions. This inhibition was more intense in the lignin extracted at 150°C than in that extracted at 100°C.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1992.070450411
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Dielectric studies on the miscibility in poly(vinyl acetate)/ poly(ethyl methacrylate) blends (1996)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 60 (1996), S. 903-909 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The glass transition relaxation of different blends of poly(vinyl acetate) and poly(ethyl methacrylate) have been investigated by dielectric relaxation spectroscopy in the frequency range from 20 Hz to 1 MHz. The obtained results suggest that the poly(vinyl acetate)-rich blends show immiscibility between the two components, whereas the poly(ethyl methacrylate)-rich blends show partial miscibility. The results obtained by differential scanning calorimetry and the analysis of the Maxwell-Wagner-Sillars effect seem to confirm the dielectric relaxation results. © 1996 John Wiley & Sons, Inc.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
  • 10
    Electronic Resource
    Electronic Resource
    Poly(vinyl alcohol)/poly(acrylic acid) blends: Miscibility studies by DSC and characterization of their thermally induced hydrogels (1993)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 50 (1993), S. 777-792 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Binary blends of poly(vinyl alcohol) (PVA) with poly(acrylic acid) (PAA) and polyacrylamide (PAAm) were characterized by differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), and infrared spectroscopy (IR). Molecular weight, blend composition, and heating time at 150°C were the variables used. Results obtained by DSC indicated that PAA/PVA blends are miscible in the full range of composition. Similarly, TGA traces showed that thermal stability was higher for blends than for pure polymers. Blends of PVA with high molecular weight PAA exhibited a hydrogel behavior after drying at relatively low temperature (100°C), whereas blends containing low molecular weight PAA behaved as hydrogels only after they were heated at 150°C. Hydrogel character was increased for these two PVA/PAA blends with the heating time at higher temperature (150°C). IR spectra revealed that esterification took place in these blends after thermally treated at this temperature. In contrast, addition of glyoxal in combination with heating was necessary to produce hydrogels from PAAm/PVA blends. Furthermore, the crosslinking degree of these hydrogels was estimated from their absorbency values by applying the Flory-Rehner equation. © 1993 John Wiley & Sons, Inc.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1993.070500505
    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...