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111.
Mibu N Yokomizo K Kashige N Miake F Miyata T Uyeda M Sumoto K 《Chemical & pharmaceutical bulletin》2007,55(1):111-114
N-Monoacyl-2,6-diaminopyridines (2a-c) and N,N'-diacyl-2,6-diaminopyridines (3a-c) were synthesized from 2,6-diaminopyridine by acylation with the corresponding acyl halide or by dehydration with the corresponding carboxylic acid using 1,3-dicyclohexylcarbodiimide (DCC). The antiviral activities of N-monoacyl- and N,N'-diacyl-2,6-diaminopyridines (2a-c and 3a-c) were estimated using plaque reduction assay with HSV-1. All N-monoacyl derivatives (2a-c) showed significant anti-herpes simplex virus (HSV)-1 activity (EC(50) = 15.3-18.5 microg/ml). The CC(50) values of 2a-c measured using Vero cells ranged at 37.5-50.0 microg/ml. These compounds showed no significant antibacterial activities with Escherichia coli or Staphylococcus aureus even at a concentration of 1 mg/ml. The N,N'-diacyl derivatives (3a-c) showed no significant anti-HSV-1 activity. 相似文献
112.
Nobuhiro Kawatsuki Imin Sai Tohei Yamamoto 《Journal of polymer science. Part A, Polymer chemistry》1999,37(21):4000-4006
We present (1) the linearly polarized (LP) ultraviolet (UV) photoreaction of block copolyesterethers comprising a hard segment of polyester and soft segment of poly(tetramethylene ether) (PTMG) and (2) the alignment behavior of liquid crystals (LCs) on the resultant photoreacted polymer films. Two kinds of copolyesterethers with different polyester segments of poly(hexamethylene p-phenylenediacrylate) (1a) or poly(hexamethylene p-phenylenediacrylate)-co-poly(hexamethylene 1,4-dibenzoate) (1b) were used in this study. The LP–UV irradiation resulted in a negative optical anisotropy for both polymer films, and a homogeneous photoalignment of LCs was achieved on the photoreacted polymer film. The LC alignment was perpendicular to the electric vector of the incident polarized light for 1a, whereas a reversion of the alignment from parallel to perpendicular was observed for 1b, depending on the irradiation doses. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 4000–4006, 1999 相似文献
113.
Rena Haruki Hironori Kouno Masanori Hosoyamada Taku Ogawa Nobuhiro Yanai Nobuo Kimizuka 《化学:亚洲杂志》2019,14(10):1723-1728
Molecular self‐assembly is a powerful means to construct nanoscale materials with advanced photophysical properties. Although the protection of the photo‐excited states from oxygen quenching is a critical issue, it still has been in an early phase of development. In this work, we demonstrate that a simple and typical molecular design for aqueous supramolecular assembly, modification of the chromophoric unit with hydrophilic oligo(ethylene glycol) chains and hydrophobic alkyl chains, is effective to avoid oxygen quenching of triplet–triplet annihilation‐based photon upconversion (TTA‐UC). While a TTA‐UC emission is completely quenched when the donor and acceptor are molecularly dispersed in chloroform, their aqueous co‐assemblies exhibit a clear upconverted emission in air‐saturated water even under extremely low chromophore concentrations down to 40 μm . The generalization of this nano‐encapsulation approach offers new functions and applications using oxygen‐sensitive species for supramolecular chemistry. 相似文献
114.
Porphyrin–AuIII complexes, which were partially or totally modified with C6F5 at the meso positions, were synthesized. The highly electron‐withdrawing substituents induced electron‐deficient states and Lewis acid properties. Single‐crystal X‐ray analysis of the ion pairs revealed ion‐pairing assemblies with characteristics dependent on the number and substitution pattern of the C6F5 units and the geometries of the anions. 相似文献
115.
Hiroyuki Okamoto Kohei Noda Moritsugu Sakamoto Tomoyuki Sasaki Yasuhiro Wada Nobuhiro Kawatsuki Hiroshi Ono 《Optical Review》2017,24(4):510-516
We developed a method for the design of multilevel anisotropic diffraction gratings based on a genetic algorithm. The method is used to design the multilevel anisotropic diffraction gratings based on input data that represent the output from the required grating. The validity of the proposed method was evaluated by designing a multilevel anisotropic diffraction grating using the outputs from an orthogonal circular polarization grating. The design results corresponded to the orthogonal circular polarization grating structures that were used to provide outputs to act as the input data for the process. Comparison with existing design methods shows that the proposed method can reduce the number of human processes that are required to design multilevel anisotropic diffraction gratings. Additionally, the method will be able to design complex structures without any requirement for subsequent examination by a human designer. The method can contribute to the development of optical elements by designing multilevel anisotropic diffraction gratings. 相似文献
116.
Yoshiaki Sugimoto Nobuhiro Tsumori Shintaro Nomura Toshiharu Saiki 《Optical Review》2009,16(3):269-273
Near-field photoluminescence (PL) imaging spectroscopy was used to investigate multi-exciton and charged-exciton states confined
in a single GaAs interface fluctuation quantum dot. We determined the origin of peaks in the PL spectra by employing a wavefunction
mapping technique. We observed distortion of the exciton wavefunction due to the electric field produced by an excess electron
at a nearby confined state. Near-field wavefunction mapping was demonstrated to be a powerful tool for visualizing the local
environment, which affects the emission properties of quantum dots. 相似文献
117.
A detailed analysis of three-dimensional vector holograms is presented which were recorded in a photoreactive polymer dissolved
liquid crystal. The diffraction properties of resultant periodic anisotropic structures were investigated. Experimental observations
confirmed that the diffraction efficiencies of the structures varied with slight changes of the grating pitch, and also that
they strongly depended on the incident angle of the probe beam. These diffraction properties were explained by the finite-difference
time-domain optical simulations. 相似文献
118.
Yuki Nagao Nobuhiro Naito Fumitada Iguchi Noriko Sata Hiroo Yugami 《Solid State Ionics》2009,180(6-8):589-591
New proton-conductive polyamide oligomers, oligomeric poly[(1, 2-propanediamine)-alt-(oxalic acid)], were synthesized to investigate the proton transport properties of bulk and thin films. The obtained oligomers were characterized by the X-ray diffraction, FT-IR spectra, 1H NMR, Matrix Assisted Laser Desorption/Ionization Time of Flight (MALDI-TOF) mass spectrum, and electrical conductivity measurements. The bulk proton conductivity is 3.0 × 10? 4 S cm? 1 at the relative humidity (RH) of 80%. The proton conductivity of thin film is relatively higher than that of bulk sample. Thickness dependence of the proton conductivity was observed in these thin films. The maximum proton conductivity of the thin film is 4.0 × 10? 3 S cm? 1 at the relative humidity (RH) of 80%, which is higher one order magnitude than that of the bulk sample. The activation energies of bulk and 200 nm thick film are 1.0 and 0.69 eV at the RH of 60%, respectively. 相似文献
119.
Tadashi Ishigaki Zoran S. Nikolic Tomoaki Watanabe Nobuhiro Matsushita Masahiro Yoshimura 《Solid State Ionics》2009,180(6-8):475-479
In case of reactions, it is a necessary condition that the free energy of formation, ΔfG, of the product is lower than the total free energies of formation of the reactants. The free energy of all reactions and/or all compounds have not been determined in the literature. In this paper, we report the formation, stability, and reactions for all compounds based on their free energies. However, it also seems possible to discuss them based on their lattice energies, because it can be calculated for many compounds if their composition, structure and their lattice parameters are known. Also, we can discuss the formation, stability, etc., for compounds excluding small effects due to temperature and entropy. As a result of the calculations, the lattice energy correlates with the perovskite distortion. 相似文献
120.
Yan Lee Dr. Takehiko Ishii Dr. Horacio Cabral Dr. Hyun Jin Kim Ji‐Hun Seo Nobuhiro Nishiyama Dr. Hiroki Oshima Kensuke Osada Dr. Kazunori Kataoka Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(29):5309-5312
Special delivery! Polyionic complex (PIC) micelles that contain the charge‐conversional moieties citaconic amide or cis‐aconitic amide were developed for cytoplasmic protein delivery. The increase of the charge density on the protein cargo helped the stability of the PIC micelles without cross‐linking, and the charge‐conversion in endosomes induced the dissociation of the PIC micelles to result in efficient endosomal release (see picture).