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561.
Yusong Wu Toshihiro Seo Shiro Maeda Takashi Sasaki Satoshi Irie Kensuke Sakurai 《Journal of Polymer Science.Polymer Physics》2005,43(11):1354-1364
Through regioselective modifications, some acylated chitosan derivatives, O‐cinnamoyl chitosans with degree of substitution (DS) varying from 0.8 to 2.0 and N‐fatty acyl‐O‐dicinnamoyl chitosans with different fatty acyl chain lengths (C2–C12), were prepared, and their chiroptical properties in dilute solutions were investigated by circular dichroism (CD). Exciton coupling between two vicinal cinnamoyl chromophores appended to the helical mainchains gave rise to bisignate Cotton effects (CEs), which were used to deduce the absolute sense of the twisting structures in solution phase. It was found that the absolute helicities vary with DS, length of the fatty chain, and solvent property, but are nearly independent of thermal stimulus. The molecular interactions (hydrogen bonding and hydrophobic interaction) involved possibly in the self‐assembled ordered structures were discussed. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1354–1364, 2005 相似文献
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563.
S. V. Shorunov M. M. Krayushkin F. M. Stoyanovich M. Irie 《Russian Journal of Organic Chemistry》2006,42(10):1490-1497
A convenient procedure has been developed for the synthesis of 3,4-diaryl(or hetaryl)maleimides by cross coupling of N-substituted 3,4-dibromomaleimides with aryl(hetaryl)boronic acids in the presence of Pd(Ph3P)4 and CsF. The reaction ensures high yields of the products and requires relatively small amount of the catalyst; it can be performed on an enlarged scale. The resulting maleimides are readily converted into the corresponding maleic anhydrides. 相似文献
564.
Shintaro Nomura Masumi Yamaguchi Tatsushi Akazaki Hiroyuki Tamura Hideaki Takayanagi Yoshiro Hirayama 《Physica E: Low-dimensional Systems and Nanostructures》2006,34(1-2):292
The electron–hole states in the fractional quantum Hall regime is investigated with a back-gated undoped quantum well by photoluminesccence in magnetic fields. The evolution of the photoluminescence spectra is discussed depending on the electron density. We find anomalies of the photoluminescence at the integer as well as the fractional filling factors. 相似文献
565.
Eiichi Takahashi Leonid L. Losev Yuji Matsumoto Isao Okuda Yoshiro Owadano 《Optics Communications》2006,257(1):133-138
A new two-color pumping method for multi-frequency Raman generation was developed using deuterium gas combined with KrF excimer lasers. To obtain a powerful two-color radiation, the pump and its first Stokes (Stokes shift Ω = 179 cm−1) were simultaneously amplified by a KrF amplifier. Thirty pure rotational Raman sidebands were generated by focusing two-color radiation in cooled deuterium. 相似文献
566.
Modulation induced low-frequency fluctuations (LFFs) of a semiconductor laser in the presence of optical feedback are investigated. LFFs are controlled to a synchronous oscillation when an appropriate modulation very close to the resonance frequency of the external cavity is applied to the injection current. The dependence of the frequency locking on the modulation frequency and depth is studied. 相似文献
567.
Carboxylated Photoswitchable Diarylethenes for Biolabeling and Super‐Resolution RESOLFT Microscopy 下载免费PDF全文
Dr. Benoît Roubinet Dr. Mariano L. Bossi Dipl.‐Biophys. Philipp Alt Dr. Marcel Leutenegger Dr. Heydar Shojaei M. Sc. Sebastian Schnorrenberg Dr. Shamil Nizamov Prof. Dr. Masahiro Irie Dr. Vladimir N. Belov Prof. Dr. Stefan W. Hell 《Angewandte Chemie (International ed. in English)》2016,55(49):15429-15433
Reversibly photoswitchable 1,2‐bis(2‐ethyl‐6‐phenyl‐1‐benzothiophene‐1,1‐dioxide‐3‐yl)perfluorocyclopentenes (EBT) having fluorescent “closed” forms were decorated with four or eight carboxylic groups and attached to antibodies. Low aggregation, efficient photoswitching in aqueous buffers, specific staining of cellular structures, and good photophysical properties were demonstrated. Alternating light pulses of UV and blue light induce numerous reversible photochemical transformations between two stables states with distinct structures. Using relatively low light intensities, EBTs were applied in biology‐related super‐resolution microscopy based on the reversible saturable (switchable) optical linear fluorescence transitions (RESOLFT) and demonstrated optical resolution of 75 nm. 相似文献
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570.
The TOMBO (thin observation module by bound optics) system is a compound imaging system inspired by a biological visual system.
Various interesting features can be utilized in the applications of the TOMBO system: in this paper, we present an effective
method for three-dimensional information acquisition. An image captured by the TOMBO system is composed of multiple images
observed from several viewpoints. Distance between the TOMBO system and an object can be estimated using disparity of the
captured images. A new method for estimation of the object distance is introduced. In the experiment, multiple object distances
can be successfully estimated by the proposed method. Using the obtained distances for image reconstruction, we can generate
a composite image focussing on multiple objects. 相似文献