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151.
J. Murata H. Baba J. A. Behr F. Goto S. Inaba H. Kawamura M. Kitaguchi C. D. P. Levy H. Masuda Y. Nakaya K. Ninomiya J. Onishi R. Openshaw M. Pearson Y. Sakamoto H. Shimizu Y. Shimizu S. Tanaka Y. Tanaka R. Tanuma Y. Totsuka E. Watanabe M. Yokohashi 《Hyperfine Interactions》2016,237(1):125
The MTV experiment (Mott Polarimetry for T-Violation Experiment) is running at TRIUMF, to search for a large T-violating transverse electron-polarization in polarized 8Li β-decay. We aim at reaching precision of 10?4 for the R-correlation, which is defined as a T-violating triple vector correlation in the β-decay rate function. A Mott polarimeter system using a CDC (Cylindrical Drift Chamber) is used to measure the left-right scattering asymmetry in the Mott scattering from a thin metal foil. In the present study, we aim to discuss systematic effects in Mott polarimetry using the CDC. 相似文献
152.
为提高算法的普适能力,提出了一种新的基于特征散度的模糊彩色图像分割算法(FDCIS).算法引入了特征散度和模糊相异性函数来度量差异性,利用特征散度进行数据聚类,实现图像的区域融合.实验证明,算法较好地降低了彩色图像大样本数据的运算量,简单而有效地解决了过度分割现象,避免了聚类算法对初始条件的依赖性,与人的主观视觉感知具有良好的一致性. 相似文献
153.
154.
Ibrahim Iliya Toshiyuki Tanaka Munekazu Iinuma Miyuki Furusawa Zulfiqar Ali Ken‐ichi Nakaya Jin Murata Dedy Darnaedi 《Helvetica chimica acta》2002,85(8):2394-2402
Five new stilbene glucosides, gnemonosides F, G, H, I, and J were isolated from the stem lianas of Gnetum gnemonoides Brongn and Gnetum africanum Welw along with nine known stilbenoids. The structures of the new compounds were elucidated as gnetin E 4a,4b,4c‐O‐β‐triglucopyranoside ( 2 ), gnetin E 4a,4c‐O‐β‐diglucopyranoside ( 3 ), gnetin C 4a,4b,11a‐O‐β‐triglucopyranoside ( 4 ), gnetin D 4a,4b‐O‐β‐diglucopyranoside ( 5 ), and gnetuhainin A 4a,4b‐O‐β‐diglucopyranoside ( 6 ) on the basis of spectroscopic evidence. 相似文献
155.
Yanfeng Wang Tianming Chen Masaya Kitamura Tadao Nakaya 《Journal of polymer science. Part A, Polymer chemistry》1996,34(3):449-460
A novel vinyl monomer 2-{(3-acrylamidopropyl)dimethyl ammonio}ethyl 2′-isopropyl phosphate (AAPI) having phosphatidylcholine analogous moiety and a series of new acrylamide monomers containing two long alkyl chains [stearyloleylacrylamide (SOAAm), distearylacrylamide (SSAAm), and n-docosyloleylacrylamide (DOAAm)] were synthesized and characterized. The polyacrylamides ( Va, Vb , and Vc ) were obtained from radical copolymerization of SOAAm, SSAAm, or DOAAm with AAPI in the presence of AIBN as an initiator. The investigations of these copolymers were carried out by x-ray analysis method, DSC, TG-DTA, and viscosity measurement, respectively. The copolymer Vb containing distearyl groups as hydrophobic side chains shows a crystalline state at room temperature, and the ordered structure disappears at high temperature. The phase transition from a crystalline state to a liquid-crystalline state was observed obviously only for copolymer Vb . In addition, the II-A isotherms and A-T isobars of these copolymers were measured and their stable LB films were also prepared. © 1996 John Wiley & Sons, Inc. 相似文献
156.
Tian-Ming Chen Yan-Feng Wang Masaya Kitamura Tadao Nakaya Ikuko Sakurai 《Journal of polymer science. Part A, Polymer chemistry》1996,34(7):1155-1164
A series of new phospholipid analogous acrylamide monomers ( 4a–e ) containing long alkyl chains as hydrophobic groups and containing phosphatidylcholine analogues as hydrophilic group were synthesized in high yields. The homopolymerizations and copolymerization ( 4b with 4e ) were carried out in the presence of a radical initiator. The structures and thermal properties of these polymers were investigated by x-ray diffraction analysis, DSC, and polarizing microscopy measurements. It has been revealed that these homopolymers ( 5b, 5c , and 5d ) which bear saturated long-hydrocarbon chains in the side chains exhibited not only orderly stacked bilayer structures at room temperature but also clear liquid crystalline behavior within a wide temperature range. The viscosity behavior of all polymers was found similar to usual polyelectrolytes in porlar solvent. The polymers obtained were also characterized by 1H-NMR, IR, and melting point, respectively. © 1996 John Wiley & Sons, Inc. 相似文献
157.
Yasuhiro Ono Michiko Nakaya Tsuyoshi Kajitani Tamotsu Sugawara Noriko Watanabe Hiroyuki Shiraishi Ryuichi Komatsu 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(12):1413-1415
The title compounds, LiKB4O7 and LiRbB4O7, are newly developed non‐linear optical crystals containing two kinds of anionic groups, namely (B3O8)7? and (B5O10)5?. The (B3O8)7? groups form infinite spiral chains parallel to the [100] direction, which are interconnected by sharing O atoms with (B5O10)5? groups. 相似文献
158.
159.
Ito T Tanaka T Ido Y Nakaya KI Iinuma M Riswan S 《Chemical & pharmaceutical bulletin》2000,48(7):1001-1005
Two new stilbene glucosides [(+)-alpha-viniferin 13b-O-beta-glucopyranoside and resveratrol 12-C-beta-glucopyranoside] and two new resveratrol oligomers, hemsleyanols A and B, were isolated from the bark of Shorea hemsleyana along with four known resveratrol oligomers. The structures of the isolates, including the relative configurations, were established by spectroscopic data involving long-range coupling and nuclear Overhauser effect experiments. 相似文献
160.
Miyuki Furusawa Yoshimi Ido Toshiyuki Tanaka Tetsuro Ito Ken‐ichi Nakaya Iliya Ibrahim Masayoshi Ohyama Munekazu Iinuma Yoshiaki Shirataka Yoshikazu Takahashi 《Helvetica chimica acta》2005,88(5):1048-1058
One new flavanone, 4′‐hydroxyisorottlerin ( 2 ), and two new chalcone derivatives, kamalachalcones C ( 3 ) and D ( 4 ), were isolated from Mallotus philippensis (kamala tree). The largest compound ( 4 ; Mr 1098 g/mol) was shown to possess a unique, fused‐ring system made of two hydroxy‐chalcone units, giving rise to eight fused benzene/pyran units. From the same plant, the following six known compounds were also isolated: kamalachalcone A ( 5 ) and B ( 6 ), isoallorottlerin ( 7 ), isorottlerin ( 8 ), 5,7‐dihydroxy‐8‐methyl‐6‐prenylflavanone ( 9 ); 6,6‐dimethylpyrano(2″,3″: 7,6)‐5‐hydroxy‐8‐methylflavanone ( 10 ), and rottlerin ( 1 ). The structures of the new compounds were confirmed by in‐depth spectral analyses, including 2D‐NMR techniques, and the full 13C‐NMR assignments of the known flavanones 1 and 7 – 10 are published for the first time. 相似文献