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1.
A thin-layer two-phase microcell was fabricated without an adhesive, which showed no fluorescence and resisted acids. The lower hollow of the microcell was thin (0.18 mm), which was in the range of the working distance of the used objective of high magnification (60x) and high numerical aperture (1.2). A reflection method using probe light was newly employed for focusing the objective on a transparent dodecane/water interface strictly with an inverted microscope. The system was applied to in situ fluorescence microscopic measurements of the dynamics of single DNA molecules (165600 base pairs) at the dodecane/water interface. 相似文献
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Abstract— The chromophore of the visual pigment of the fruit fly Drosophila melanogaster was studied by high-pressure liquid chromatography (HPLC). Oxime derivatives of the chromophore were successfully analyzed with a more polar solvent than has been used for retinaloximes. A preceding monochromatic irradiation resulted in reversible interchanges in the amount among geometric isomers of the oximes that reflected the photointerconversion of rhodopsin and metarhodopsin of the peripheral photoreceptors (Rl-R6). Authentic all- trans -3-h-ydroxyretinal was used to identify the chromophore from metarhodopsin. Results demonstrated that the chromophore of the visual pigment in Drosophila is 3-h-ydroxyretinal as was proposed in larger flies. 相似文献
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Oguchi T Tozuka Y Hanawa T Mizutani M Sasaki N Limmatvapirat S Yamamoto K 《Chemical & pharmaceutical bulletin》2002,50(7):887-891
The solid-state complexation between cholic acid (CA) and either methyl p-hydroxybenzoate (MPB) or ibuprofen (IBP) was investigated. Powder X-ray diffractometry, IR spectroscopy and thermal analysis suggested the complex formation between CA and MPB as well as between CA and IBP by co-grinding method. The stoichiometry of CA-MPB was 1 : 1 while that of CA-IBP was 2 : 1, reflecting the effect of guest size on complex formation. The guest compounds were assumed to be included in the channel of complexes formed by hydrogen bonds among CA molecules. 相似文献
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A cross-linked 1,3,5-tristyrylbenzene dendrimer 5 was synthesized to study the photochemical isomerization mechanism. On irradiation, 5 isomerized with the quantum yields (ΦE→Z) of 0.063, which was not very much different from that for a model compound 1 (ΦE→Z 0.080), supporting a volume-conserving hula-twist (HT) mechanism during the photochemical E-Z isomerization. 相似文献
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Magnetic circular dichroism and NIR luminescence of nitroxide radical complexes, [Cr(III)(beta-diketonato)(2)(NIT2py or IM2py)]PF(6), demonstrate that the energy gaps between the singlet ((1)L(D)) and triplet ((3)L(D)) spin coupled levels in the lowest excited (2)E(g),(2)T(1g) states are much larger than those in the ground state. This is the first observation of magnetic interactions in the excited states of radical complexes, which could be elucidated in terms of the exchange mechanism. 相似文献
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[reaction: see text] A stereoselective total synthesis of (+)-benzastatin E (1) is described. The synthesis involves a diastereoselective Grignard addition to 2-acylindoline 2, which is derived from commercially available (S)-2-indolinecarboxylic acid (3). The unknown absolute configuration of (+)-1 is determined as (9S,10R). 相似文献
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A simple and sensitive combined solvent-extraction and atomic-absorption spectrometric method has been developed for the determination of gold in silver, copper, lead, selenium and anode slime. Samples are decomposed with hydrochloric and nitric acids, and gold is extracted as the trioctylmethylammonium-gold bromide complex and determined by atomic-absorption spectrometry by direct spraying of the extract into the flame. Optimal conditions for the extraction and determination of gold have been established. As little as 0.5 mug of gold in a sample can be determined. The extraction of gold from hydrochloric or hydrobromic acid solution with trioctylamine or trioctylmethylammonium chloride (or bromide) has also been investigated. 相似文献
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Hideaki Iizuka Shoko Watanabe Mayuko Koshikawa Yurie Matsumoto Yuki Aoyama Hideaki Ichiba Toshitaka Nabeshima Takeshi Fukushima 《Analytical and bioanalytical chemistry》2013,405(25):8137-8141
It has been reported that repeated phencyclidine (PCP) treatment induces schizophrenia-like behavior in mice. l-Tryptophan (Trp) concentrations in brain tissues of control (n?=?8) and PCP-treated mice (10 mg/kg/day, s.c., 14 days, n?=?10) were determined using high-performance liquid chromatography (HPLC) with fluorescence detection. The HPLC method involved pre-column fluorescence derivatization with (R)-(?)-4-(N,N-dimethylaminosulfonyl)-7-(3-isothiocyanatopyrrolidin-1-yl)-2,1,3-benzoxadiazole (DBD-PyNCS). Eight different parts of the brain, namely, the frontal cortex, nucleus accumbens, striatum, hippocampus, amygdala, thalamus, hypothalamus, and cerebellum, of both groups were investigated. A significant decrease in the l-Trp concentration in the nucleus accumbens (p?=?0.024) and hippocampus (p?=?0.027) was observed in PCP-treated mice, suggesting that alteration of the l-Trp metabolism might occur in these brain parts. 相似文献
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