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Active full-shell grazing-incidence optics [PDF]
Proceedings of SPIE, 2016 MSFC has a long history of developing full-shell grazing-incidence x-ray optics for both narrow (pointed) and wide field (surveying) applications. The concept presented in this paper shows the potential to use active optics to switch between narrow and ...
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The optical activity of polypeptides
Biopolymers, 1983AbstractThe present status of the theory of the optical properties of polypeptides is discussed in a general way. Arguments are presented that indicate that the interaction of exciton bands in helices will occur in a tensorial way with the parallel polarized bands normally having stronger interactions than the perpendicular polarized bands, with only ...
J A, Schellman, W J, Becktel
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Aromaticity and Optical Activity
Journal of the American Chemical Society, 2015The relationship between aromaticity and optical activity is investigated in comparisons of heterocycles with 4n + 2 and 4n π-electrons, in cyclic ketones with and without aromatic resonance structure representations, in tautomers and pericyclic reaction partners in which only one compound of each pair is aromatic, and in partially hydrogenated cyclo ...
Veronica L, Murphy +2 more
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Journal of Agricultural and Food Chemistry, 1999
The accepted derivation of lignins from non(enzymatically)-controlled radical coupling reactions has been recently challenged, and it is relevant to ascertain unequivocally whether lignins are or are not (as normally assumed) optically active. Two approaches were used. First, DFRC (derivatization followed by reductive cleavage) dimers derived from beta-
J, Ralph +4 more
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The accepted derivation of lignins from non(enzymatically)-controlled radical coupling reactions has been recently challenged, and it is relevant to ascertain unequivocally whether lignins are or are not (as normally assumed) optically active. Two approaches were used. First, DFRC (derivatization followed by reductive cleavage) dimers derived from beta-
J, Ralph +4 more
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Optical activity and evolution
Journal of Theoretical Biology, 1980It is noted that the chemical reactions occurring in rarefied cosmic clouds (molecular concentration less than or approximately to 10(2) cm-3) differ from similar laboratory reactions by the much greater effect on the outcome of external force fields.
G P, Gladyshev, M M, Khasanov
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Optical Activity of Biopolymers
Nature, 1969Theoretical and experimental advances have led to a reassessment of the interpretation of optical rotatory dispersion and circular dichroism of nucleic acids, proteins and related compounds. The present state of the field is reviewed in this article.
W B, Gratzer, D A, Cowburn
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Nature, 1972
Simple pictorial arguments can demonstrate that the natural and Faraday rotation experiments conserve parity and time-reversal invariance. The method can be used to predict possible new effects without recourse to mathematical theories.
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Simple pictorial arguments can demonstrate that the natural and Faraday rotation experiments conserve parity and time-reversal invariance. The method can be used to predict possible new effects without recourse to mathematical theories.
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Coupled Ferroelectricity and Optical Activity in Optically Active Ferroelectrics
The Journal of Physical Chemistry LettersFerroelectricity was initially discovered in 1921 in Rochelle salt (potassium sodium tartrate tetrahydrate), a chiral compound containing a chiral unit. However, the inherent relationship between coupled ferroelectricity and optical activity in chiral ferroelectrics derived from achiral units, as well as in polar ferroelectrics, remains insufficiently ...
Xiang-Bin Han, Wen Zhang
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Experiments on the Origins of Optical Activity
Origins of Life, 1974Two recent reports claim that (1) aqueous L-aspartic acid polymerizes faster than D-Asp in the presence of kaolin at 90 degrees, and (2) L-phenylalanine is adsorbed by kaolin more extensively than D-Phe at pH 4(the reverse being true at pH2). The novelty of these observations and their potential significance for the origin of optical activity has ...
W A, Bonner, J J, Flores
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