Now showing items 41-50 of 119
Normal vibrations of crystalline polyglycine I
(Wiley Subscription Services, Inc., A Wiley Company, 1972-09)
A valence force field has been refined for crystalline polyglycine I using its known antiparallel chain pleated-sheet structure and without replacing the CH 2 group by a point mass. Polyglycine I and four of its isotopic ...
Structural changes in glassy polycarbonate induced by cyclic stresses
(Elsevier, 1991-06-11)
Glassy polycarbonate was subjected to cyclic stresses and the changes in its structure were studied by DSC, positronium annihilation lifetime spectroscopy (PALS), and SAXS. On increased exposure to cyclic loading, the ...
Dipole derivatives and infrared intensities of the ester group. An ab initio and force field study of methyl acetate
(Elsevier, 1988-10-31)
Dipole derivatives have been obtained (using both 3-21G and 6-31G basis sets) for methyl acetate. Using a force field refined from experimental data on methyl acetate and its deuterated derivatives, infrared intensities ...
Ab initio force fields of glycine dipeptide in C5 and C7 conformations
(Elsevier, 1989-02)
Schafer and coworkers have previously derived, with the 4-21 Gaussian basis set ab initio optimized geometries for the glycine dipeptide, CH3CONHCH2CONHCH3, in several conformations. Using their geometries for the C5 and ...
Electromagnetic effects in the Surface Enhanced Raman Scattering from a molecule at a liquid Hg surface
(Elsevier, 1981-09-02)
In a previous publication the image enhancement effect and the enhanced radiation due to near field excitation of surface roughness were calculated for a finite-size molecule above a metal described by a nonlocal dielectric ...
Macromolecular structure and organization of alpha keratin
(Wiley Subscription Services, Inc., A Wiley Company, 1974-02)
The small-angle equatorial X-ray scattering of alpha keratin (African porcupine quill) was studied using a direct type of analysis, which allows the separation of the intermicro-fibrillar interference effects from those ...
An investigation of Chromatium vinosum high-potential irondashsulfur protein by EPR and Mossbauer spectroscopy; evidence for a freezing-induced dimerization in NaCl solutions
(Elsevier, 1991-09-20)
The high-potential irondashsulfur protein (HiPIP) from Chromatium vinosum contains a cubane prosthetic group that shuttles between the [4Fe-4S]3+,2+ states. We find that the EPR spectra from this protein can be explained ...
Normal vibrations of polyglycine II
(Wiley Subscription Services, Inc., A Wiley Company, 1972-09)
A valence force field has been refined for single-chain polyglycine II using the known structure and four isotopic derivatives. The calculated frequencies are in good agreement with the observed. The force field is compared ...
Vibrational studies of the disulfide group in proteins : Part III. A simplified ab initio force field for diethyl disulfide and SS and CS stretch frequency--conformation correlations for diisobutyl disulfide
(Elsevier, 1990-10-01)
We have obtained a simplified ab initio force field for diethyl disulfide, based on our previous scaled ab initio force field, which can be used in normal coordinate analysis of proteins containing the disulfide bridge. A ...
A physical explanation of the EPR spectrum observed during catalysis by enzymes utilizing coenzyme B
(Elsevier, 1975-08-26)
We have proposed that the "doublet" EPR spectra observed during catalysis by a number of coenzyme B1,2-requiring enzymes arises from a weak electrostatic exchange interaction between an organic free radical and low spin ...