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91.
Abstract— We have found that clay acts as a novel model matrix for the amphiphilic protein-opsin to mimic the visible absorption spectrum of a protonated retinal Schiff base (RSB) in vivo. Without strong acids at ambient temperature, a visible broad absorption spectrum with a LDmax at 530 nm covering the range from 400 to 680 nm was achieved for the protonated RSB with cationic surfactant-modified montmorillonite clay. The interlayers of the dimethyloctadecylamine (DOA) modified clay were found to provide amphiphilic space allowing the amphiphilic RSB to be intercalated easily and sequentially and protonated by the DOA. It is proposed that the visible absorption spectrum at LD, 530 nm was attributable to electrostatic effects, permitting the appropriate distance between the nitrogen of the protonated RSB and the negatively charged clay interlayers and also to the anisotropic orientation of the RSB molecules in the interlayers. 相似文献
92.
NMR measurements coupled with pattern-recognition analysis offer a powerful mixture-analysis tool for latent-feature extraction and sample classification. As fundamental applications of this analysis for mixtures, the 1H spectra of 176 kinds of green, black, oolong and other tea infusions were acquired by a 500 MHz NMR spectrometer. Each spectrum pattern was analyzed by a multivariate statistical pattern-recognition method where Principal Component Analysis (PCA) was used in combination with Soft Independent Modeling of Class Analogy (SIMCA). SIMCA effectively selected variables that contribute to tea categorization. The final PCA resulted in clear classification reflecting the fermentation and processing of each tea, and revealed marker variables that include catechin and theanine peaks. 相似文献
93.
Takahiro Hirotsu Shunsaku Katoh Kazuhiko Sugasaka Masako Sakuragi Kunihiro Ichimura Yoshio Suda Mitsugi Fujishima Yoshimoto Abe Takahisa Misonoo 《Journal of polymer science. Part A, Polymer chemistry》1986,24(8):1953-1966
Preparation of new chelating polymers bearing dihydroxamic acid groups and the adsorptive ability for uranium in sea water are described. Chloromethylated polystyrene crosslinked with divinylbenzene was treated with diethyl malonate in N, N-dimethylformamide to give the polymer having diethyl malonate groups. This polymer was then treated with hydroxylamine in methanol to afford the dihydroxamic acid polymer. The presence of hydroxamic acid groups was confirmed by the appearance of IR absorption band at 1680 cm?1. The dihydroxamic acid polymer contained carboxylic acid groups as well as hydroxamic acid ones, and the contents of carboxylic acid and hydroxamic acid groups were estimated from elemental analysis to be 2–3 and 2–4 mmol/g, respectively. The polymer showed the adsorptive ability of 40 μg-U/g in 8 days for uranium in sea water. In addition, the polymer showed the selective adsorptivity for iron, nickel, copper, and zinc as well as uranium. The macroreticular-type polymer showed much higher adsorption rate for uranium in sea water than the gel-type ones did, suggesting that the rate depends on the diffusion of the uranium in the polymer support. 相似文献
94.
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96.
Tsurusaburo Takasu 《Monatshefte für Mathematik》1939,48(1):170-175
Ohne Zusammenfassung 相似文献
97.
98.
Purpose: Generally, stroke patients can walk and stand up fluidly but fulfill the sit-to-walk (STW) task with difficulty. The purpose of this study was to investigate the relationship between movement fluidity and motor strategy in the initial contact of the STW task. Method: Thirty stroke patients and ten healthy subjects performed the STW task from a sitting position, and their movement was measured by a motion analysis system. The differences in data between patients and healthy subjects were analyzed using the Mann-Whitney U test. The relationship between fluidity index (FI) and other indices (kinetic and kinematic data in STW, functional independence measure [FIM], and Fugl-Meyer Assessment [FMA]) were analyzed using Spearman''s rank correlation coefficient. Results: The stroke patients had lower FI values than the healthy subjects and exhibited shortened step length and prolonged duration from onset to the first stance leg off. FI values correlated with trunk flexure angle at initial contact, first step length, and maximum vertical floor reaction force. The independent level of the FIM of stair climbing and walking ability and the FMA of balance also correlated with FI. Conclusion: There is a possibility that poor balance is one of the reasons why stroke patients are unable to start walking fluently from the sitting position. To perform the STW fluidly, patients must start walking before the trunk extension is fully completed. The relationship between FI and indices of physical ability, namely stair climbing and balance, may have therapeutic benefits for coaching the STW task to stroke patients. 相似文献
99.
Toya H Okano K Takasu K Ihara M Takahashi A Tanaka H Tokuyama H 《Organic letters》2010,12(22):5196-5199
The enantioselective total synthesis of (-)- and (+)-petrosin is described. The union of two key segments was executed by Suzuki-Miyaura coupling. The quinolizidine rings were stereoselectively constructed via a diastereoselective Mannich reaction and an aza-Michael reaction. The 16-membered ring was constructed by ring-closing metathesis with the second-generation Grubbs catalyst. 相似文献
100.
M. Okano H. Hara M. Muramatsu K. Doi S. Uetake Y. Takasu Y. Takahashi 《Applied physics. B, Lasers and optics》2010,98(4):691-696
We have successfully implemented the first simultaneous magneto-optical trapping (MOT) of lithium (6Li) and ytterbium (174Yb) atoms towards production of ultracold polar molecules of LiYb. For this purpose, we developed the dual atomic oven which
contains both atomic species as an atom source and successfully observed the spectra of the Li and Yb atoms in the atomic
beams from the dual atomic oven. We constructed the vacuum chamber including the glass cell with the windows made of zinc
selenium (ZnSe) for the CO2 lasers, which are the useful light sources of optical trapping for evaporative and sympathetic cooling. Typical atom numbers
and temperatures in the compressed MOT are 7×103 atoms, 640 μK for 6Li, 7×104 atoms, and 60 μK for 174Yb, respectively. 相似文献