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711.
Degree of color constancy was measured when color memory was involved in color comparison judgment. We used the Optical Society of America (OSA) Uniform Color Scales as stimulus color samples, and chose 20 color samples as test stimuli. Four illuminants of 1700, 3000, 6500, and 30, 000 K were tested. The observer, completely adapted to a test illuminant, saw a test color sample and stored its color in his memory. After being readapted to the reference white (6500 K), he started selecting a color sample from among the 424 OSA samples which matched the test sample in his memory. We employed a memory matching method called cascade color matching, in which the number of selected color-samples was gradually reduced in four stages. In the final stage, the observer selected a color sample. The results show that, for most test colors, the distributions of selected colors in stages 1 to 4 were similar among all illuminants, and that the u’v’ chromaticity distance between a test color under 6500 K and its matched color was quite short. These indicate that good color constancy was retained in memory color comparison. 相似文献
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715.
Dr. Ryukou Izumi Dr. Takahiko Matsushita Dr. Naoki Fujitani Dr. Kentaro Naruchi Dr. Hiroki Shimizu Dr. Sakae Tsuda Dr. Hiroshi Hinou Prof. Dr. Shin‐Ichiro Nishimura 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(12):3913-3920
Microwave‐assisted solid‐phase synthesis allows for the rapid and large‐scale preparation and structure–activity characterization of tandem repeating glycopeptides, namely monodispersed synthetic antifreeze glycopeptides (syAFGPs, H‐[Ala‐Thr(Galβ1,3GalNAcα1→)‐Ala]n‐OH, n=2–6). By employing novel AFGP analogues, we have demonstrated that of the monodispersed syAFGPn (n=2–6, degree of polymerization, DP=2–6, Mw=1257–3690 Da), syAFGP5 (DP=5, Mw=3082 Da) and syAFGP6 (DP=6, Mw=3690 Da) exhibit the ability to form typical hexagonal bipyramidal ice crystals and satisfactory thermal hysteresis activity. Structural characterization by NMR and CD spectroscopy revealed that syAFGP6 forms a typical poly‐L ‐proline type II helix‐like structure in aqueous solution whereas enzymatic modification by sialic acid of the residues at the C‐3 positions of the nonreducing Gal residues disturbs this conformation and eliminates the antifreeze activity. 相似文献
716.
717.
Yoshihisa Okamoto Hiroko Amemiya Toshio Kinoshita Michiko Shirai Yoshio Matsumoto 《Polyhedron》1985,4(4):629-632
Reaction of 5,6-diamino-1,3-dimethyluracil (DDU) with iron(III) ion gave a fine blue colouration due to the formation of Fe[(DDU—H)3]·2HClO4. An oxidation product (7), C12H12N6O4, was also isolated from the reaction mixture. 相似文献
718.
Noriyuki Asakura Toshiaki Kamachi Ichiro Okura 《Research on Chemical Intermediates》2006,32(3):341-355
The behavior of redox molecules in solution that was not detected by electrochemical techniques was measured by a highly-sensitive
electrochemical quartz crystal microbalance (EQCM) technique that has been improved in this study to obtain a high sensitivity
of EQCM measurement in solution. The improved EQCM technique allowed to monitor the motion of a redox molecule, that is an
access of the molecule to an electrode surface and repulsion from the surface during redox. An EQCM technique currently in
use has measured adsorption of redox molecules on an electrode surface or polymerization on the surface caused by a chemical
reaction following redox, which exhibits an enough large mass change response to detect with an EQCM measurement. However,
access and repulsion of redox molecule, which is a slight motion of the molecule near on electrode surface, has not been detected
and investigated by an EQCM technique, because the mass change response seems to be very small. In this study, the redox behavior
of methyl viologen on a bare gold surface, pyridinethiol surface and methylpyridinethiol surface was investigated. Although
the three electrodes give the same cyclic voltammogram of methyl viologen, the three are different in QCM response recorded
at the same time as the voltammetry. Access/repulsion of methyl viologen within an electrical double layer was monitored by
the highly-sensitive EQCM technique. 相似文献
719.
Naoki Kanoh Aya Asami Makoto Kawatani Kaori Honda Saori Kumashiro Hiroshi Takayama Siro Simizu Tomoyuki Amemiya Yasumitsu Kondoh Satoru Hatakeyama Keiko Tsuganezawa Rei Utata Akiko Tanaka Shigeyuki Yokoyama Hideo Tashiro Hiroyuki Osada 《化学:亚洲杂志》2006,1(6):789-797
We have developed a unique photo‐cross‐linking approach for immobilizing a variety of small molecules in a functional‐group‐independent manner. Our approach depends on the reactivity of the carbene species generated from trifluoromethylaryldiazirine upon UV irradiation. It was demonstrated in model experiments that the photogenerated carbenes were able to react with every small molecule tested, and they produced multiple conjugates in most cases. It was also found in on‐array immobilization experiments that various small molecules were immobilized, and the immobilized small molecules retained their ability to interact with their binding proteins. With this approach, photo‐cross‐linked microarrays of about 2000 natural products and drugs were constructed. This photo‐cross‐linked microarray format was found to be useful not merely for ligand screening but also to study the structure–activity relationship, that is, the relationship between the structural motif (or pharmacophore) found in small molecules and its binding affinity toward a protein, by taking advantage of the nonselective nature of the photo‐cross‐linking process. 相似文献
720.
K. Jinno M. Sato S. Amemiya T. Katoh 《Journal of Radioanalytical and Nuclear Chemistry》1980,59(1):23-30
The present work deals with the determination of vanadium in high grade carbons by three radioanalytical methods, viz. thermal
neutron activation analysis with an accelerator, thermal neutron activation analysis with a reactor and proton induced X-ray
emission analysis with an accelerator. It is cleared from this study that thermal neutron activation with an accelerator is
more convenient for the rapid and non-destructive analysis of ppm-level vanadium in bulk carbons than thermal neutron activation
analysis with a reactor. Proton induced X-ray emission is less useful for the analysis of bulk samples. 相似文献