- Effect of temperature on the photoalignment of azo dyes in thin films
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The temperature dependences of the induced dichroic ratios (DRs) of azo dyes after their photoalignment in thin films 80 to 200 nm thick are studied. It is found that the DR values of layers containing dyes of the benzeneazodiphenyl series fall from 6.0 to 1.6 as the temperature rises from 60 to 130°C, respectively. A reduction in induced DR as the temperature rises (from 20 to 100°C) is also observed for the thin films of the dyes of benzeneazo-5,5'-dioxodibenzothiophene group. The absence of induced DR after irradiation with polarized light at 100°C indicates there is no alignment of molecules at this temperature.
- Mikulich,Murauski, An. A.,Muravsky, Al. A.,Agabekov
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- Optical spectra of protected diamine 10-bond-bridged intervalence radical cations related to N,N,N′,N′-tetraalkylbenzidine
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The optical absorption spectra of the delocalized intervalence radical cations of seven o,o′-linked benzidine derivatives that have the nitrogens protected as 9-(9-aza-bicyclo[3.3.1]nonan-3-one) derivatives are discussed and compared with that of the p-phenylene radical cation. The linking units are CH2, CH2CH2, NMe, S, SO2, and C=O, and we also studied H,H (the unlinked benzidine). The lowest-energy absorption band is assigned as the transition from the antibonding combination of symmetrical N and aromatic orbitals to the antibonding combination of the antisymmetric N and aromatic orbitals using TD-DFT calculations, and a good correlation between the observed transition energies and those calculated using the simple Koopmans theorem-based "neutral in-cation geometry" calculations on the UB3LYP/6-31G* structures is found. The use of the two-state model that equates the electronic interaction through the bridge between the amino groups with half of the lowest transition energy is seriously incorrect for these and other delocalized intervalence compounds. The problem of extracting the electronic interactions that actually are involved from calculated transition energies is discussed.
- Nelsen, Stephen F.,Luo, Yun,Weaver, Michael N.,Lockard, Jenny V.,Zink, Jeffrey I.
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p. 4286 - 4295
(2007/10/03)
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- Substituted dibenzothiophenes having antiangiogenic activity
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The invention provides novel substituted dibenzothiophenes of Formulae (I), (II), (III) and (IV) which have antiangiogenic activity and further provides a method using substituted dibenzothiophenes of Formula (V) as antiangiogenic agents.
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- Substituted dibenzothiophenes
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This disclosure described novel derivatives of dibenzothiophene, dibenzothiophene sulfoxide, dibenzothiophene sulfone, thioxanthene, thioxanthene sulfoxide and thioxanthene sulfone which are active as modulators of the mammalian immune response system.
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