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61.
Our recent studies of ferroelectric chiral smectic and super-twisted nematic (ST) multiplexed-matrix liquid-crystal displays (LCDs) and a thin-film-transistor (TFT) active-matrix twisted nematic (TN) LCD are presented, mainly in terms of liquid-crystal material and cell optimization. This is based on a consideration of their electro-optical characteristics. In addition the matrix LCD devices developed through these studies are introduced, including a 12-inch-diagonal video-rate multicolour ferroelectric LCD, a highly multiplexed genuine achromatic ST LCD with a single cell and a 4-inch-diagonal full-colour a-Si TFT-addressed TN LCD for a video display. 相似文献
62.
63.
A secretoglobin 3A2 type C (98–139) peptide was synthesized by native chemical ligation between 115Ile and 116Cys residues using Dawson’s linker. The peptide-N-acyl-benzimidazolinone-glycine amide, a C-terminal thioesters precursor, was provided from 3-amino-4-(methylamino)benzoic acid. In addition, an N-terminal cysteine fragment, the (116–139) peptide, was prepared by ordinary Fmoc-solid phase peptide synthesis. Native chemical ligation of the (98–115) fragment with the Dawson’s linker and the (116–139) peptide smoothly proceeded to give SCGB3A2 type C (98–139) peptide. 相似文献
64.
Taku Hirama Takayuki Umemura Noriyuki Kogure Mariko Kitajima Hiromitsu Takayama 《Tetrahedron letters》2017,58(3):223-226
A new procedure for the asymmetric total synthesis of lythraceous alkaloids with a 4-arylquinolizidine skeleton was developed, which involved an organocatalyzed asymmetric intramolecular aza-Michael addition. 相似文献
65.
Asanuma H Toda T Murayama K Liang X Kashida H 《Journal of the American Chemical Society》2010,132(42):14702-14703
A new foldamer, acyclic threoninol nucleic acid (aTNA), has been synthesized by tethering each of the genetic nucleobases A, G, C, and T to d-threoninol molecules, which were then incorporated as building blocks into a scaffold bearing phosphodiester linkages. We found that with its fully complementary strand in an antiparallel fashion, the aTNA oligomer forms an exceptionally stable duplex that is far more stable than corresponding DNA or RNA duplexes, even though single-stranded aTNA is rather flexible and thus does not take a preorganized structure. 相似文献
66.
Mariko Ohara 《manuscripta mathematica》2014,143(3-4):379-388
We present some rational elliptic surfaces over a certain field such that certain open subschemes do not satisfy the surjectivity of the boundary map on K 2 arising from the localization sequence. We consider two cases that the base field is transcendental over its prime subfield and that the base field is characteristic zero. 相似文献
67.
68.
M. Koizumi T. T. Inamura K. Morita M. Takami M. Wakasugi A. Yoshida M. Azuma H. Katsuragawa T. Horiguchi T. Ishizuka I. Nakamura M. Nakaoka A. Iivonen K. Valli S. Matsuki T. Murayama K. Shimomura T. Shinozuka I. Sugai Y. Tagishi 《Hyperfine Interactions》1992,74(1-4):181-191
We have constructed a fast atomic-beam collinear laser spectroscopy system connected to the on-line isotope separator facility
GARIS/IGISOL at RIKEN. This system is potentially powerful in studying refractory elements. To test the system, an off-line
collinear experiment was made on stable Hf isotopes produced by means of laser ablation technique. For production of radioactive
Hf isotopes, the use of the inverse kinematics of a fusion reaction,9Be(166Er,xn)175-x
Hf, was investigated. The radioactive isotope169Hf was successfully extracted from GARIS/IGISOL and accelerated up to 30 keV. 相似文献
69.
Fractal analysis of turbulent premixed flame surface 总被引:3,自引:0,他引:3
The fractal-like character of the laminar flamelet surface in turbulent premixed combustion of lean methane/air mixtures was studied by using the laser tomography technique to visualize the instantaneous flame surface in the two-dimensional section cut by the laser sheet. The fractal analysis of the surface revealed that the surface actually exhibits a self-similarity behavior in a narrow range of scale, and the value of fractal dimension can be defined. The inner cutoff scale was the laminar flame thickness, while the outer cutoff scale was the flame size. The fractal dimension was found to depend on the orientation of the section, and to increase towards downstream. It is suggested that the observed fractal-like character is not directly connected to approach flow turbulence, but should represent certain aspects of the flamelet itself. 相似文献
70.
György Bázár Zoltan Kovacs Mariko Tanaka Akane Furukawa Airi Nagai Manami Osawa Yukari Itakura Hiroshi Sugiyama Roumiana Tsenkova 《Analytica chimica acta》2015
Near infrared spectroscopy is an overtone spectroscopy regarded as a quick and non-destructive method that provides analytical solutions for components that represent approximately 1% or more of the total mass of the investigated composite samples. Aquaphotomics offers the possibility for disentanglement of information remaining hidden in the spectra when conventional data evaluation methods are used, since this concept utilizes changes of the water structure induced by the measured solute as specific molecular vibrations at water bands. Here, near infrared technique and aquaphotomics are applied for non-destructive identification and quantification of mono- and di-saccharide solutes at 100–0.02 mM concentration that is accepted as unachievable with near infrared spectroscopy. The results presented in this study support the aquaphotomics' water molecular mirror concept that explores spectral changes related to water molecular rearrangements caused by minute changes of the solutes in the aqueous systems. The method provides quick and accurate alternative for classical analytical measurements of saccharides even at millimolar concentration levels. 相似文献