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
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Chemie 127 (1996), S. 1173-1187 
    ISSN: 1434-4475
    Keywords: Acetyl anthracenes ; 2D NOESY NMR of anthracenes ; β-Oxo-anthracenepropionate ; β-Oxo-dicarbonyl-compounds ; Thiophenes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary β-Oxo-1-anthracenepropionate (3) reacts step by step with phenylisothiocyanate and α-CH-acidic halo compounds to keten-S,N-acetals4, followed by cyclocondensation to give the 4-(1-anthracenyl)-thiophene-3-carboxylates5. In contrast, the reaction of β-oxo-9-anthracenepropionate (6) with isothiocyanates and α-CH-acidic halo compounds yields 5-acyl-2-amino-3-(9-anthracenoyl)-4-hydroxy-thiophenes8. This is caused by the sterical hindrance of the keto group of the anthracene in position 9; thus, the cyclocondensation proceedsvia reaction of the ester group of the β-oxo-propionate. In the same way, 9-acetylanthracene reacts with phenylisothiocyanate and α-CH-acidic compounds to keten-S,N-acetals10 and, in an additional step, to 2-anilino-3-(9-anthracenoyl)-thiophenes11 and 2-(9-anthracenoyl)-methylene-3,4-diphenyl-2,3-dihydro-(1,3)-thiazole12, respectively. The structure of all new compounds was determinated by 2D NOESY NMR spectroscopy.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 42 (1996), S. 1789-1792 
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Chichester [u.a.] : Wiley-Blackwell
    International Journal for Numerical Methods in Engineering 39 (1996), S. 1383-1403 
    ISSN: 0029-5981
    Keywords: crashworthiness ; homogenization ; topology design ; automotive structure optimization ; Engineering ; Engineering General
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mathematics , Technology
    Notes: The topological optimization of components to maximize crash energy absorption for a given volume is considered. The crash analysis is performed using a DYNA3D finite element analysis. The original solid elements are replaced by ones with holes, the hole size being characterized by a so-called density (measure of the reduced volume). A homogenization method is used to find elastic moduli as a function of this density. Simpler approximations were developed to find plastic moduli and yield stress as functions of density.Optimality criteria were derived from an optimization statement using densities as the design variables. A resizing algorithm was constructed so that the optimality criteria are approximately satisfied. A novel feature is the introduction of an objective function based on strain energies weighted at specified times. Each different choice of weighting factors leads to a different structure, allowing a range of design possibilities to be explored.The method was applied to an automotive body rear rail. The original design and a new design of equal volume with holes were compared for energy absorption.
    Additional Material: 25 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...