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101.
The paper demonstrates that a confocal Raman microspectroscope combined with optical tweezers is a promising technique to estimate polymer concentration in polymer-rich domain in phase-separated-aqueous polymer solution. The sample polymer is poly-(N-isopropylacrylamide) (PNIPAM) that is well-known as a representative thermo-responsive polymer. Optical tweezers can selectively trap the polymer-rich domain at the focal point in non-contact and non-intrusive modes. Such situation allows us to determine polymer concentration in the domain, which has been unclear due to a lack of appropriate analytical technique. It is applicable for a variety of other thermo-responsive polymers. 相似文献
102.
Kanako Nakamae Dr. Yukie Takemura Dr. Bunsho Kure Prof. Takayuki Nakajima Prof. Yasutaka Kitagawa Prof. Tomoaki Tanase 《Angewandte Chemie (International ed. in English)》2015,54(3):1016-1021
A linear tetraphosphine, meso‐bis[(diphenylphosphinomethyl)phenylphosphino]methane (dpmppm) was used to synthesize linear octapalladium‐extended metal atom chains as discrete molecules of [Pd8(μ‐dpmppm)4](BF4)4 ( 1 ) and [Pd8(μ‐dpmppm)4L2](BF4)4 (L=2,6‐xylyl isocyanide (XylNC; 2 ), acetonitrile ( 3 ), and N,N‐dimethylformamide (dmf; 4 )), which are stable in the solution states and show interesting temperature‐dependent photochemical properties in the near IR region. Variable temperature NMR studies demonstrated that at higher temperature T≈140 °C the Pd8 chains were dissociated into Pd4 fragments, which were thermodynamically self‐aligned to restore the Pd8 chains at lower temperature T<60 °C. The coldspray ionization mass spectra suggested a possibility for further aggregation of the linear tetrapalladium units. 相似文献
103.
Hasegawa S Saito S Takanashi J Morokoshi Y Furukawa T Saga T Aoki I 《Magnetic resonance imaging》2011,29(2):179-184
Aberrant expression of ferritin, a major iron-binding protein, has shown to be involved in neurodegenerative diseases. In this study, we generated transgenic (Tg) mice of human ferritin heavy chain (FTH) gene and investigated the effects of ferritin overexpression in FTH-Tg brain by 1H-MRI and 1H-MRS. The mice displayed no apparent neurological symptoms, and no specific morphological and T2 alterations were found in the brain by MRI, and not even by histological studies. 1H-MRS, however, revealed that some metabolic markers were significantly altered in FTH-Tg brains compared to wild-type control brains, such as decreases in myo-inositol and glutamine, and an increase in lactate. Our present studies suggested that despite the absence of neurological, morphological, T2, and histological signatures, brain metabolisms were significantly affected in FTH-Tg mice. This study also highlights the usefulness of 1H-MRS in the analysis of transgenic mouse models. 相似文献
104.
A spirosolane derivative possessing a hydroxyl group at C-23, esculeogenin A, a sapogenol of tomato saponin, was found to be easily converted into the corresponding pregnane derivative by refluxing with aqueous pyridine. Therefore, introduction of a hydroxyl group into the C-23 of diosgenin (as representative of spirostane derivatives) and solasodine (as representative of spirosolane derivatives) was attempted by the reaction of NaNO(2)-BF(3)?·?Et(2)O. In diosgenin, the objective compound was obtained by the reaction in AcOH. However, in solasodine, we obtained a 23-nitroso derivative by the reaction in AcOH and 23,24-bisnorcholanic acid 22-16 lactone, or vespertilin, in AcOH and CHCl(3). 相似文献
105.
Eiji Higuchi Kouta Adachi Shinji Nohara Hiroshi Inoue 《Research on Chemical Intermediates》2009,35(8-9):985-995
Pt nanoparticles-loaded carbon black (CB) was prepared from Pt carbonyl cluster complexes, and had much narrower size distribution than commercial Pt nanoparticles/CB. In the former the monodispersed Pt nanoparticles were highly dispersed on CB without aggregation even at high Pt loading of 80 wt.%. Hydrodynamic voltammograms in O2-saturated 0.05 M H2SO4 solution at 30 °C showed that the onset potential of oxygen reduction reaction (ORR) current for the monodispersed Pt nanoparticles/CB electrode was more positive than that for a polycrystalline Pt electrode and similar to that for the commercial Pt nanoparticles/CB electrode. Moreover, the mass activity for ORR for the monodispersed Pt nanoparticles/CB electrode was ca. 4.9 times higher than that for the commercial Pt nanoparticles/CB electrode, clearly indicating that the control of size distribution of Pt nanoparticles is meaningful for reducing the Pt consumption. 相似文献
106.
Kumagai K Saitoh M Oyaizu T Furukawa Y Takashima S Nohara M Takagi H Matsuda Y 《Physical review letters》2006,97(22):227002
A Fulde-Ferrell-Larkin-Ovchinnkov (FFLO) state was previously reported in the quasi-2D heavy fermion CeCoIn5 when a magnetic field was applied parallel to the ab plane. Here, we conduct 115In NMR studies of this material in a perpendicular field, and provide strong evidence for FFLO in this case as well. Although the topology of the phase transition lines in the H-T phase diagram is identical for both configurations, there are several remarkable differences between them. Compared to H parallelab, the FFLO phase for H perpendicularab is confined in a much narrower region at the low-T-high-H corner in the H-T plane, and the critical field separating the FFLO and non-FFLO superconducting states almost ceases to have a temperature dependence. Moreover, directing H perpendicularab results in a notable change in the quasiparticle excitation spectrum within the planar node associated with the FFLO transition. 相似文献
107.
Baba T Yokoya T Tsuda S Kiss T Shimojima T Ishizaka K Takeya H Hirata K Watanabe T Nohara M Takagi H Nakai N Machida K Togashi T Watanabe S Wang XY Chen CT Shin S 《Physical review letters》2008,100(1):017003
We have performed temperature- (T-)dependent laser-photoemission spectroscopy of the antiferromagnetic (AF) superconductor ErNi2B2C to study the electronic-structure evolution reflecting the interplay between antiferromagnetism and superconductivity. The spectra at the superconducting (SC) phase show a very broad spectral shape. A T-dependent SC gap shows a sudden deviation from the BCS prediction just below TN. This observation can be explained well by the theoretical model and thus represents the characteristic bulk electronic structure of the AF SC phase for the first time. 相似文献
108.
T. Tanaka Y. Kawasaki Y. Ideta T. Ohno M. Nohara H. Takagi 《Journal of Physics and Chemistry of Solids》2008,69(12):3142-3145
7Li- and 51V-NMR have been measured to make clear the electronic state in a two-dimensional triangular lattice LiVS2. Knight shift of both 7Li- and 51V-NMR is almost independent of temperature below the phase transition temperature Tc of about 310 K from the paramagnetic state to non-magnetic state. The 51V- spin-lattice relaxation rate 1/T1 reveals an exponential temperature dependence below Tc, indicating a gap structure of electronic state. These results are consistent with a non-magnetic state with a trimer singlet of V3+ spins below Tc. 相似文献
109.
T Yamashita T Matsumoto S Yahara N Yoshida T Nohara 《Chemical & pharmaceutical bulletin》1991,39(6):1626-1628
The structures of two new steroidal glycosides named soladulcosides A and B, isolated from the aerial parts of Solanum dulcamara including new sapogenols, were elucidated as (22R, 25R)-3 beta, 15 alpha, 23 alpha-trihydroxy-5 alpha-spirostan-26-one 3-O-alpha-L-rhamnopyranosyl-(1----2)-beta-D-glucopyranoside and (22R, 25R)-3 beta,23 alpha-dihydroxy-5 alpha-spirostan-26-one 3-O-alpha-L-rhamnopyranosyl-(1----2)-[alpha-L-rhamnopyranosyl-(1----4)]- beta-D-glucopyranoside, respectively. 相似文献
110.
Synthesis of 2-[[(4-fluoroalkoxy-2-pyridyl)methyl]sulfinyl]-1H- benzimidazoles as antiulcer agents 总被引:1,自引:0,他引:1
Many 2-[[(4-fluoroalkoxy-2-pyridyl)methyl]sulfinyl]-1H-benzimidazoles were synthesized and tested for anti-secretory, antiulcer, and cytoprotective activities. Most of these compounds were superior to omeprazole in anti-secretory and antiulcer potencies, and especially in protecting the gastric mucosa from ethanol-induced damage. Among these compounds, 2-[[[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridyl]methyl]sulfinyl] - 1H-benzimidazole, AG-1749 (lansoprazole) (6f), was selected for further development and clinical evaluation. 相似文献