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91.
92.
Abstract Some di(4-alkyloxyphenyl ester)s of aromatic dicarboxylic acids which presumably exert significant steric hindrance to molecular packing, such as di(2- and/or 3-methyl or -chloro-4-alkyloxyphenyl) 2,5-pyridinedicarboxylates, di(2- and/or 3-methyl-4-alkyloxyphenyl) 2,6-naphthalenedicarboxylates, and di(4-alkylxyphenyl) 3,5-pyrazoledicarboxylates, are shown to indicate nematic liquid-crystalline behaviour. 相似文献
93.
Inside Back Cover: Stereodivergent Synthesis and Stereochemical Reassignment of the C79–C104 Fragment of Symbiodinolide (Chem. Eur. J. 6/2016) 下载免费PDF全文
94.
Kazuo Hayakawa Yuki Akiyama Yoshinori Tsukamoto Mikio Kurata Kenichi Yukihira Hiroyoshi Soejima Yutaka Yoshida 《Hyperfine Interactions》2012,206(1-3):79-82
We have been developing a “M?ssbauer Spectroscopic Microscope (MSM)” which consists of a focusing lens for 14.4?keV γ-rays and a high precision X–Y stage. The measuring system both for electrons and γ-rays combined with a new M?ssbauer driver, i.e., “a moving coil actuator with a liner encoder” enables us to measure the mapping images simultaneously corresponding to different spectral components. The system has a controlling system based on a LabVIEW program and a LIST mode data acquisition system (NIKI-GLASS/A3100). To investigate a correlation between the microstructure of a sample and 57Fe atoms, a scanning electron microscope (APCO/Mini-EOC) is also installed to this system. 相似文献
95.
Abstract 2-Azido-4-O-benzoyl-2,6-dideoxy-3-O-methyl-D-allopyranose, needed as one of the building blocks for construction of a novel cyclodextrin-like compound, was prepared in the form of crystalline β-anomer 6 from methyl 2-azido-4,6-O-benzylidene-2-deoxy-α-D-allopyranoside 1. As a model of α-glycosidation necessary for formation of a cyclic structure, 6 was converted into the corresponding β-glycosyl trichloroacetimidate and coupled with methyl 6-O-benzyl-2,3-di-O-methyl-α-D-glucopyranoside 8, giving α(1→4)-linked disaccharide derivative 9. 相似文献
96.
Prof. Hidetoshi Kawai Tatsuya Utamura Erina Motoi Tomoko Takahashi Hiroyoshi Sugino Manabu Tamura Prof. Masakazu Ohkita Prof. Kenshu Fujiwara Takao Saito Prof. Takashi Tsuji Prof. Takanori Suzuki 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(14):4513-4524
The macrocyclization of 2,6‐diethynyl hydrindacenes ( 1 ) with functional groups at mutually perpendicular positions results in the formation of novel macrocycles which, as a result of the hindered rotation of the hydrindacene units, possess directionally persistent peripheral functionalities. The two hydrindacene units in the dimer macrocycle ( 2 ) have been shown to interact electronically through their respective butadiyne moieties, whereas the trimer macrocycle ( 3 ) demonstrates a moderate degree of geometrical flexibility as a result of the five‐membered hydrindacene rings. In addition, these trimer macrocycles contain a central cavity suitably sized for the inclusion of various solvent molecules. These new macrocycles can be further modified by introducing π‐conjugated side groups, such as styryl and thienyl groups, as well as by attaching a variety of peripheral ester groups. 相似文献
97.
Critical miscibility phenomena in binary blends of chlorinated polyethylenes (CPEs) with a wide range of degree of chlorination (37 to 69 wt 970 CI) were studied by measuring the glass transition behavior. At a given temperature the miscibility of the blends was principally dependent on the difference in chlorine content between the two component CPEs and also on the mean degree of chlorination. The miscibility of these systems at 150°C was maximal around an average mole fraction chlorination, β, of 0.5. The systems displayed upper critical solution temperatures when β was below 0.5, while lower critical solution temperatures were observed when β | was above 0.5. At a given β, | the consolute points converged as the difference in chlorine content of the blend constituents increased. It appears that this double consolute point temperature decreases with increasing average degree of chlorination. A more refined analysis, taking into account the possible presence of CCl2 units and the microstructure of the CPEs, is also presented. 相似文献
98.
Some di(4-alkyloxyphenyl ester)s of aromatic dicarboxylic acids which presumably exert significant steric hindrance to molecular packing, such as di(2- and/or 3-methyl or -chloro-4-alkyloxyphenyl) 2,5-pyridinedicarboxylates, di(2- and/or 3-methyl-4-alkyloxyphenyl) 2,6-naphthalenedicarboxylates, and di(4-alkylxyphenyl) 3,5-pyrazoledicarboxylates, are shown to indicate nematic liquid-crystalline behaviour. 相似文献
99.
Hiroyoshi Itoh Kohji Yamamoto Jun-ichiro Inoue Gerrit E.W. Bauer 《Physica E: Low-dimensional Systems and Nanostructures》2005,30(1-2):120-125
We numerically model the conductivity of a two-dimensional electron gas (2DEG) in the presence of the Rashba spin–orbit (SO) interaction in the diffusive transport regime. We performed simulation using samples which width W and length L are up to 200 and 30 000, respectively, on a tight-binding square lattice. When the system is in the diffusive regime, the quadratic increase of the conductivity with SO interaction strength λSO derived previously by Born approximation is reproduced except for very weak SO interaction. In order to obtain satisfactory agreement between numerical and analytical results, the sample width and length should be much larger than the mean free path ℓ but the length should be shorter than the localization length ξ, e.g. 4ℓW and 10ℓLξ. The anomaly at weak SO interaction is also observed in the conductance fluctuation and the localization length, and is attributed to the finite size crossover from symplectic to orthogonal class with decreasing SO interaction. The typical values of the SO interaction characterizing the crossover obtained for ℓ48 are λSO1.0/W and 0.2/W when we impose open and periodic boundary conditions, respectively. 相似文献
100.