The exploration of response surfaces for the determination of Hückel molecular orbital parameters

Tetrahedron ◽  
1964 ◽  
Vol 20 (3) ◽  
pp. 671-685 ◽  
Author(s):  
Wendell F. Smith
Keyword(s):  
Molecular Orbital ◽  
Response Surfaces ◽  
Orbital Parameters

scholarly journals Erratum: Determination of the orbital parameters of binary pulsars

2009 ◽  
Vol 395 (3) ◽  
pp. 1775-1775 ◽  
Author(s):  
P. C. Freire ◽  
M. Kramer ◽  
A. G. Lyne
Keyword(s):  
Orbital Parameters ◽  
Binary Pulsars

Direct determination of molecular orbital symmetry ofH2S using polarized x-ray emission

1991 ◽  
Vol 43 (1) ◽  
pp. 235-241 ◽  
Author(s):  
R. Mayer ◽  
D. W. Lindle ◽  
S. H. Southworth ◽  
P. L. Cowan
Keyword(s):  
Molecular Orbital ◽  
Direct Determination ◽  
Orbital Symmetry ◽  
X Ray

scholarly journals Orbits of Galactic Globular Clusters from Schmidt Plate Astrometry

1994 ◽  
Vol 161 ◽  
pp. 453-459 ◽  
Author(s):  
M. Odenkirchen ◽  
R.-D. Scholz ◽  
M.J. Irwin
Keyword(s):  
Globular Clusters ◽  
Proper Motions ◽  
Mass Model ◽  
Orbital Parameters ◽  
The Galaxy ◽  
Galactic Globular Clusters

We present results from orbit integrations for the globular clusters M 3 and M 92. Absolute proper motions recently measured from Tautenburg Schmidt plates and a three-component mass model for the Galaxy have been used to derive the galactic orbits of these clusters. Orbital parameters and the influence of observational uncertainties on the determination of the orbits are discussed.

scholarly journals Curing Kinetic Parameters of Epoxy Composite Reinforced with Mallow Fibers

Materials ◽  
2019 ◽  
Vol 12 (23) ◽  
pp. 3939 ◽  
Author(s):  
Lucio Fabio Cassiano Nascimento ◽  
Fernanda Santos da Luz ◽  
Ulisses Oliveira Costa ◽  
Fábio de Oliveira Braga ◽  
Édio Pereira Lima Júnior ◽  
...  
Keyword(s):  
Kinetic Parameters ◽  
Industrial Process ◽  
Diglycidyl Ether ◽  
Response Surfaces ◽  
Heating Rates ◽  
Scanning Calorimetry ◽  
Exponential Factor ◽  
Curing Kinetic ◽  
Technological Tool

Knowledge about the curing behavior of a thermosetting resin and its composites includes the determination of kinetic parameters and constitutes an important scientific and technological tool for industrial process optimization. In the present work, the differential scanning calorimetry (DSC) technique was used to determine several curing parameters for pure epoxy and its composite reinforced with 20 vol % mallow fibers. Analyses were performed with heating rates of 5, 7.5, and 10 °C/min, as per the ASTM E698 standard. The kinetic related parameters, that is, activation energy (E), Avrami’s pre-exponential factor (Z), and mean time to reach 50% cure (t½), were obtained for the materials, at temperatures ranging from 25 to 100 °C. Response surfaces based on the mathematical relationship between reaction time, transformed fraction, and temperature were provided for optimization purposes. The results showed that the average curing time used for the production of diglycidyl ether of bisphenol A/triethylenetetramine (DGEBA/TETA) epoxy systems or their composites reinforced with natural mallow fibers can be considerably reduced as the temperature is increased up to a certain limit.

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