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951.
Gorenstein Fano polytopes arising from finite partially ordered sets will be introduced. Then we study the problem of which
partially ordered sets yield smooth Fano polytopes. 相似文献
952.
Houran Shafiee Akihiro Tagaya Yasuhiro Koike 《Journal of Polymer Science.Polymer Physics》2010,48(19):2029-2037
We clarified the birefringence properties of poly(methyl methacrylate), poly(ethyl methacrylate), poly(isobutyl methacrylate), poly(cyclohexyl methacrylate), poly(isopropyl methacrylate), and poly(tert‐butyl methacrylate). We demonstrated that the conformational change in polymer molecules that causes orientational birefringence differs from that causing photoelastic birefringence. Orientational birefringence depends mainly on the orientation of the main chains of the methacrylate polymers above Tg. On the other hand, photoelastic birefringence in elastic deformation below Tg depends mainly on the orientation of the side chains while the main chains are scarcely oriented. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 2029–2037, 2010 相似文献
953.
Two macrotricyclic ligands composed of two face-to-face octadentate metal chelates were synthesized. These cage-shaped disodium complexes had special recognition ability for various counter anions. Specific chiral dicarboxylates bound to the complexes within the cavity and exhibited chirality induction properties. For instance, N-Boc-Asp dianion strongly induced circular dichroism (CD) signals, but N-Boc-Glu dianion, which is one carbon longer, did not. 相似文献
954.
955.
A new scheme for numerical integration of the 1D2V relativistic Vlasov–Maxwell system is proposed. Assuming that all particles in a cell of the phase space move with the same velocity as that of the particle located at the center of the cell at the beginning of each time step, we successfully integrate the system with no artificial loss of particles. Furthermore, splitting the equations into advection and interaction parts, the method conserves the sum of the kinetic energy of particles and the electromagnetic energy. Three test problems, the gyration of particles, the Weibel instability, and the wakefield acceleration, are solved by using our scheme. We confirm that our scheme can reproduce analytical results of the problems. Though we deal with the 1D2V relativistic Vlasov–Maxwell system, our method can be applied to the 2D3V and 3D3V cases. 相似文献
956.
In our previous study, we found that the color appearance mode affects color preference. Hence, in this study, we propose
three color preference models based on the perceived color attributes for different color appearance modes. In the first model,
which was used for color preference in the object color mode, the color preference could be predicted from the perceived blackness
and the combination of the perceived chromaticness and perceived hue. The second and third models were developed for color
preferences in the unnatural object color mode and light source color mode, respectively. In these two models, the color preference
could be explained on the basis of the perceived whiteness, perceived chromaticness, and perceived hue. 相似文献
957.
Hiroshi Ishimoto Yuji Zaizen Akihiro Uchiyama Kazuhiko Masuda Yuzo Mano 《Journal of Quantitative Spectroscopy & Radiative Transfer》2010,111(16):2434-2443
We present a shape model of mineral dust particles for use in light-scattering calculations. A spatial Poisson-Voronoi tessellation was applied to simulate the aggregate structure and, therefore, the rough surface of the mineral particles. To develop the shape model, we took into account statistics of shape parameters derived from the cross-sectional areas, maximum dimensions, and perimeters of field-collected dust particles. Light-scattering properties of the modeled Voronoi aggregates were examined by the finite-difference time-domain (FDTD) method. The results of randomly oriented scattering properties agreed with previously reported laboratory measurements of mineral dust particles. 相似文献
958.
Tatsuya Suzuki Naoko Komura Akihiro Imamura Hiromune Ando Hideharu Ishida Makoto Kiso 《Tetrahedron letters》2014
A facile reaction for constructing selenoglycosides has been developed based on the transacetalization reaction between a selenoacetal and a glycosyl imidate. Glycosyl imidates were activated with TMSOTf to produce oxocarbenium ion, which reacted with benzyloxymethyl alkyl (aryl) selenide, providing alky (or aryl) selenoglycosides in high yields. Furthermore, this reaction was utilized in the synthesis of 2-(trimethylsilyl)ethylselenoglycoside, which, upon treatment with TBAF in the presence of an electrophile, was transformed into other selenoglycosides. 相似文献
959.
Akihiro Okamoto Kazuhito Hashimoto Kenneth H. Nealson 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(41):11168-11171
The iron‐reducing bacterium Shewanella oneidensis MR‐1 has a dual directional electronic conduit involving 40 heme redox centers in flavin‐binding outer‐membrane c‐type cytochromes (OM c‐Cyts). While the mechanism for electron export from the OM c‐Cyts to an anode is well understood, how the redox centers in OM c‐Cyts take electrons from a cathode has not been elucidated at the molecular level. Electrochemical analysis of live cells during switching from anodic to cathodic conditions showed that altering the direction of electron flow does not require gene expression or protein synthesis, but simply redox potential shift about 300 mV for a flavin cofactor interacting with the OM c‐Cyts. That is, the redox bifurcation of the riboflavin cofactor in OM c‐Cyts switches the direction of electron conduction in the biological conduit at the cell–electrode interface to drive bacterial metabolism as either anode or cathode catalysts. 相似文献
960.
Rekharsky MV Yamamura H Inoue C Kawai M Osaka I Arakawa R Shiba K Sato A Ko YH Selvapalam N Kim K Inoue Y 《Journal of the American Chemical Society》2006,128(46):14871-14880
For the first time, achiral cucurbiturils (CBs) were endowed with significant enantiomeric and distereomeric discrimination by incorporating a strong chiral binder. Calorimetric, nuclear magnetic, light-scattering, and mass spectral studies revealed that (S)-2-methylbutylamine (as a strong binder) can be discriminated by two enantiomeric supramolecular hosts, composed of CB[6] and (R)- or (S)-2-methylpiperazine, with an unprecedented 95% enantioselectivity in aqueous NaCl solution. This is the highest enantioselectivity ever reported for a supramolecular system derived from an achiral host. Similarly, CB[7], with a larger cavity, exhibited diastereoselectivities up to 8 times higher for diastereomeric dipeptides, as demonstrated for L-Phe-L-Leu-NH3+ versus L-Phe-D-Leu-NH3+. 相似文献