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41.
Horinouchi T Nakagawa H Suzuki T Fukuhara K Miyata N 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(17):4809-4813
We report a novel NO donor (RpNO), containing a 2,6-dimethylnitrobenzene moiety for photocontrollable NO release and a rhodamine moiety for targeting to mitochondria. Photorelease of NO from RpNO in aqueous solution was confirmed by means of ESR analysis. Cellular release of NO from RpNO was confirmed with the aid of DAF-FM DA, an NO-specific fluorescence probe. RpNO was colocalized with MitoTracker Green FM, a mitochondrial stain, in HCT116 colon cancer cells and exhibited photodependent cytotoxicity. Our results indicate that RpNO is an effective NO donor for time-controlled, mitochondria-specific NO treatment. 相似文献
42.
Ito H Ikeda M Hasegawa T Furusho Y Yashima E 《Journal of the American Chemical Society》2011,133(10):3419-3432
A series of complementary molecular strands from 2-mer to 5-mer that are composed of m-terphenyl units bearing chiral/achiral amidine or achiral carboxyl groups linked via Pt(II) acetylide complexes were synthesized by sequential stepwise reactions, and their chiroptical properties on the double-helix formation were investigated by circular dichroism (CD) and (1)H NMR spectroscopies. In CHCl(3), the "all-chiral" amidine strands consisting of (R)- or (S)-amidine units formed preferred-handed double helices with the complementary achiral carboxylic acid strands through the amidinium-carboxylate salt bridges, resulting in characteristic induced CDs in the Pt(II) acetylide complex regions, indicating that the chiral substituents on the amidine units biased a helical sense preference. The Cotton effect patterns and intensities were highly dependent on the molecular lengths. The complementary double-helix formation was also explored using the chiral/achiral amidine strands with different sequences in which a chiral amidine unit was introduced at the center (center-chiral) or a terminus (edge-chiral) of the amidine strands. The effect of the sequences of the chiral and achiral amidine units on the amplification of chirality (the "sergeants and soldiers" effect) in the double-helix formation was investigated by comparing the CD intensities with those of the corresponding all-chiral amidine double helices with the same molecular lengths. Variable-temperature CD experiments of the all-chiral and chiral/achiral amidine duplexes demonstrated that the Pt(II)-linked complementary duplexes are dynamic and their chiroptical properties including the chirality transfer from the chiral amidine unit to the achiral amidine ones are significantly affected by the molecular lengths, sequences, and temperatures. On the basis of the above results together with molecular dynamics simulation results, key structural features of the Pt(II)-linked oligomer duplexes and the effect of the chiral/achiral amidine sequences on the amplification of chirality are discussed. 相似文献
43.
Hidehiko Mishou 《Journal of Number Theory》2011,131(12):2352-2367
In this paper we investigate the joint functional distribution for a pair of Hurwitz zeta functions ζ(s,αj) (j=1,2) in the case that real transcendental numbers α1 and α2 satisfy α2∈Q(α1). Especially we establish the joint universality theorem for these zeta functions. 相似文献
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By adopting the empirical interaction potential between hydrogen and metal atoms determined in our previous paper, calculations have been performed of the 2T configuration, in which two neighboring tetrahedral (T) sites are equally shared by a hydrogen (H) atom. The tunneling matrix element J and the activation energy are estimated by calculating the excitation energy of the H atom for the 2T state and the energy difference between the 2T and 1T state, respectively.From these calculations, it is suggested that H atoms in V and Fe migrate between the ground states of neighboring T sites by adiabatic transitions, whereas in the lower temperature region in Ta by non-adiabatic tunneling process. 相似文献
47.
Hidehiko Arai Takeshi Wada Isamu Kuriyama 《Journal of Polymer Science.Polymer Physics》1976,14(8):1379-1389
Polyethylenes were prepared by γ-ray-induced polymerization in ethyl and n-butyl alcohols, tert-butyl alcohol containing 5 vol-% of water, 2,2,5-trimethylhexane, 2,2,4-trimethylpentane, and cyclohexane in the temperature range 25–90°C. The morphology of the polymers as-polymerized and studied by electron microscopy depends on three factors through the degree of undercooling: the affinity of the solvent, polymerization temperature, and the polymer molecular weight. Large lamellar crystals are formed even in the alcohols when at least two of them are chosen properly. 相似文献
48.
In order to clarify the nonmagnetic-magnetic transition found in Ce-Si system, magnetization measurements have been made to reveal a large reduction of the magnetic moment of Ce atom. Taking into account the results and also the reduction of the magnetic entropy, we propose a dense Kondo model to interpret our Ce-Si system. Kondo temperatures are deduced from various physical quantities and a comparison is made between them. Our Ce-Si system is the first example of a ferromagnetic dense Kondo system. 相似文献
49.
Hisao Fujita Yashima Rachid Benabidallah 《Rendiconti del Circolo Matematico di Palermo》1993,42(2):195-218
In questo articolo dimostriamo l'unicità della soluzione (globale in tempo) dell'equazione monodimensionale o a simmetria
sferica di un gas viscoso e termoconduttore con la superficie libera. In questo risultato il limite inferiore della densità
ρ può essere uguale a 0. Assieme al teorema di esistenza dimostrato nei lavori precedenti, costituisce il teorema di esistenza
e di unicità (globale in tempo) per questa equazione. 相似文献
50.