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71.
Reizo Kato Hayao Kobayashi Takehiko Mori Akiko Kobayashi Yukiyoshi Sasaki 《Solid State Communications》1985,55(5):387-392
In the crystals of the cation radical salts based on the organic donor BMDT-TTF, the charge separation is observed. This comes from (1) nonequivalency of the site potential and (2) the long range electron-electron interaction, which are related to the two-dimensional nature of the molecular arrangement. The effects of the charge separation on the elctronic structure are discussed. 相似文献
72.
73.
74.
Keietsu Tamagake Yoshiaki Hamada Jun Yamaguchi Akiko Y. Hirakawa Masamichi Tsuboi 《Journal of Molecular Spectroscopy》1974,49(2):232-240
Infrared absorption spectrum of NH2OH has been observed in its gaseous state, and the fine structures of the bands at 386 and 751 cm?1 assignable, respectively, to the fundamental and overtone of the torsional vibration of this molecule have been examined. Band center frequencies for the n = 1 ← 0, 2 ← 1, 3 ← 2, 2 ← 0, and 3 ← 1 transitions (where n is the vibrational quantum number of the torsional oscillation) have been determined to be 386.2, 365.1, 346.3, 751.2, and 711.3 cm?1, respectively. On the basis of these data, a discussion is given on the internal-rotation potential function. 相似文献
75.
76.
Kiriya D Chang HC Kamata A Kitagawa S 《Dalton transactions (Cambridge, England : 2003)》2006,(11):1377-1382
A novel series of valence tautomeric (VT) complexes, [Co(Cnbpy)(3,5-DTBQ)2] (Cnbpy = 4,4'-dialkyl-2,2'-bipyridine (alkyl = (C(n)H(2n+1)) where n = 0 (CoC0bpy), 1 (CoC1bpy), 5 (CoC5bpy), 9 (CoC9bpy) and 13 (CoC13bpy); 3,5-DTBQ = 3,5-di-tert-butylsemiquinonate or catecholate), including two previously reported complexes (CoC0bpy and CoC1bpy), were systematically prepared and their properties examined. Introduction of alkyl groups into VT chromophores leads to unexpected variations in the VT process, depending on the lengths of the alkyl chains. An even more interesting observation is that significant polytypic phase transitions with crystallographic symmetry changes accompanying the abrupt VT conversion are induced for the first time in CoC9bpy and CoC13bpy. 相似文献
77.
Using a straightforward chemo-enzymatic procedure, 1-beta-O-acyl glucuronides of three non-steroidal anti-inflammatory drugs, diclofenac (DF) 5, mefenamic acid (MF) 6 and (S)-naproxen (NP) 7, were prepared. Caesium salts of these carboxylic acid drugs reacted with commercially available methyl 2,3,4-tri-O-acetyl-1-bromo-1-deoxy-alpha-D-glucopyranuronate 4 to give exclusively the corresponding 1-beta-O-acyl glucuronides 8-10 in moderate yields. The protecting acetyl (for -OH group) and methyl ester (for -CO2H group) groups of each sugar moiety were easily removed to provide the corresponding free 1-beta-O-acyl glucuronides 1-3 in high yields. Deprotection was achieved through effective enzyme-catalysed chemo-selective hydrolyses of the acetyl groups using lipase AS Amano (LAS), and of the methyl ester group using esterase from porcine liver (PLE). 相似文献
78.
Inagaki K Takatsu A Nakama A Eyama S Yarita T Okamoto K Chiba K 《Analytical and bioanalytical chemistry》2006,385(1):67-75
A method is described for determination of selenium in sediment by isotope-dilution inductively coupled plasma mass spectrometry
with an octapole reaction cell (ID–ICP–ORCMS). Sediment samples were digested with HNO3, HClO4, and HF, and the digestion included an elaborate evaporation process to remove bromine from the digested solution. Simple
strong cation-exchange disk filtration was used to remove rare earth elements (REE) from the digested solution, because REE2+ seriously interfere with Se isotopes (i.e. 156Gd2+ with 78Se+, 160Gd2+ with 80Se+). Addition of acetic acid to the filtrate was examined to improve the sensitivity of ICP–ORCMS measurement of Se+ by means of a carbon-enhancement effect. The interfering for selenium isotopes were almost eliminated by use of H2 as reaction gas. Interference from BrH+ formed in the reaction cell was negligible because the Br was removed in the evaporation process. Approximately 99.5% of
REE were removed by cation-exchange disk filtration yet more than 99% of Se remained in the filtrate solution. The intensity
for Se+ was enhanced approximately fourfold by addition of 5% (v/v) of acetic acid whereas that for was barely enhanced. Measured 80Se/78Se ratios in unspiked digested solutions of the sample were in good agreement with that for an Se standard solution. The analytical
results for Se in the certified reference materials MESS-3 and PACS-1 were in good agreement with their certified values,
with small uncertainties.
相似文献
79.
Nomura A Uyeda TQ Yumoto N Tatsu Y 《Chemical communications (Cambridge, England)》2006,(34):3588-3590
To design a nanoscale biodevice that can be controlled by an external stimulus, we have introduced photochemical switching peptides derived from the kinesin C-terminus domain into the kinesin-microtubule in vitro motility system. 相似文献
80.
You Takahashi Akiko Fukuda Emiko Ishiwata Yoshimasa Nakamura 《Applicable analysis》2013,92(3):586-594
The integrable discrete hungry Lotka–Volterra (dhLV) system is easily transformed to the qd-type dhLV system, which resembles the recursion formula of the qd algorithm for computing matrix eigenvalues. Some of the qd-type dhLV variables play a role for assisting the time evolution of the others. This property does not appear in the original dhLV system. In this article, we first show the existence of a centre manifold for the qd-type dhLV system. With the help of the centre manifold theory, we next investigate the local convergence of the qd-type dhLV system, and then clarify the monotonicity related to the qd-type dhLV variables at the final phase of the convergence. 相似文献