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41.
Mori M Oyama Y Suzuki A Takahashi K Yamada M Miyano K Miyata H Takei H Hirata KS Kajita T Kihara K Nakahata M Nakamura K Ohara S Sato N Suzuki Y Totsuka Y Yaginuma Y Koshiba M Suda T Tajima T Fukuda Y Nagashima Y Takita M Kaneyuki K Tanimori T Beier EW Frank ED Frati W Kim SB Mann AK Newcomer FM Van Berg R Zhang W 《Physical review D: Particles and fields》1991,43(9):2843-2846
42.
43.
H. Yamaguchi K. Ninomiya M. Fukuda S. Itô N. Kato Y. Fukazawa 《Chemical physics letters》1980,72(2):297-300
The electronic absorption spectra of syn-[2,2] (2,6) azulenophane (1) and anti-[2,2] (2,6)azulenophane (2) were investigated via magnetic circular dichroism spectra. The anomalous fluorescence spectra were also observed. From the assignment of the absorption spectra, it was concluded that molecules 1 and 2 emitted the fluorescence from the third excited singlet state. 相似文献
44.
Crown ether dyes with pendent anionic side-arms were synthesized for extractionspectrophotometry of alkali and alkaline earth metal ions. Dramatic changes in metal selectivity were obtained simply by changing the nature of the anionic side-arm on the same crown ether skeleton. A structure/metal selectivity relationship is discussed in detail in terms of “chelate” and “intramolecular ion-pair” formation. Small metal cations (high charge density) are preferred in the extraction by a crown ether reagent with a charge-localized anionic side-arm through the formation of a “chelate”. Large metal cations (low charge density) are preferred in the extraction by reagents with a charge-delocalized anionic side-arm through the formation of an “intramolecular ion-pair”. Steric restrictions imposed by the side-arm on the metal ion approaching the crown ether are also important factor in controlling the selectivity of these reagents. 相似文献
45.
Atsuo Fukuda Hans J. Paus Akira Matsushima 《Zeitschrift für Physik B Condensed Matter》1976,25(3):211-218
Magnetic circular dichroism (MCD) of theA- andB-absorption band region has been obtained at 4.2 K and 50 kG in KI:Ga+, KI:In+, and KI:Sn2+. The MCD spectra indicate the complex nature of these bands more clearly than the absorption spectra themselves do. TheA-band MCD consists in all cases of a positive and a negative part reflecting the structure of the absorption band. TheB-band MCD shows three peaks, two positive peaks at 4.34 and 4.415 eV (4.09 and 4.175 eV) and a negative peak at 4.38 eV (4.125 eV) in KI:Ga+ (KI:In+). TheB-band in KI:Sn2+ consists of a shoulder (b
0) at 3.76 eV and a main band which has at least 5 sub-peaks (b
1~b
5) at 3.821, 3.841, 3.861, 3.880, and 3.895 eV; each of the subpeaks (b
1~b
5) gives a derivative-like MCD.The MCD shape functionf() for the transitiona
1g
2
a
1g
t
1u
has been obtained for one set of parameter values by using the classical Franck-Condon approximation and the Monte Carlo integration method. The result can explain the observed salient features of theB- as well asA-band MCD's, indicating the validity of the Franck-Condon approximation and the interaction mode coordinates. 相似文献
46.
Liquid crystal alignment layers of a high T g polymer containing an azobenzene moiety are prepared by photofabrication of a surface relief grating (SRG). The interference pattern of a circular and linearly polarized Ar+ laser beam generated the surface relief grating and the morphology was detected by atomic force microscope. The optical anisotropy of the films was investigated by polarizing optical microscopy. The orientation of the optical axis of the film mainly depends on the direction of the initial polarization plane. Nematic liquid crystals were aligned parallel to the direction of the grating, but the pretilt angles of the liquid crystals were nearly zero. Irradiation with homogeneous linearly polarized light could also align liquid crystals, but this alignment capability was weaker than that of the SRG film. 相似文献
47.
Eric M. Yezdimer Tomohiro Umemoto Hiroshi Yamada Satoshi Makino Ikuo Tooyama 《Applied biochemistry and biotechnology》2013,170(5):1138-1150
The potential utility of an imaging agent for the detection of hepatic copper was investigated in a Wilson’s disease animal model. Solid-phase peptide synthesis was used to construct an imaging agent which consisted of a copper-binding moiety, taken from the prion protein, and a gamma ray-emitting indium radiolabel. Long–Evans Cinnamon (LEC) rats were used for the Wilson’s disease animal model. Our evaluation methodology consisted of administering the indium-labeled agent to both LEC and genetically healthy Long–Evans (LE) cohorts via a tail vein injection and following the pharmacokinetics with single-photon emission computed tomography (SPECT) over the course of an hour. The animals were then sacrificed and their livers necropsied. An additional control agent, lacking the copper-binding moiety, was used to gauge whether any change in the hepatic uptake might be caused by other physiological differences between the two animal models. LEC rats injected with the indium-labeled agent had roughly double the amount of hepatic radioactivity as compared to the healthy control animals. The control agent, without the copper-binding moiety, displayed a hepatic signal similar to that of the control LE animals. Additional intraperitoneal spiking with CuSO4 in C57BL/6 mice also found that the pharmacokinetics of the indium-labeled, prion-based imaging agent is profoundly altered by exposure to in vivo pools of extracellular copper. The described SPECT application with this compound represented a significant improvement over a previous MRI application using the same base peptide sequence. 相似文献
48.
T. Izumikawa D. Shinojima S. Takahashi M. Mihara K. Matsuta M. Fukuda T. Ohtsubo S. Ohya T. Minamisono 《Hyperfine Interactions》2007,178(1-3):79-82
The β-NMR of the probe atom 12B implanted in In-doped germanium was measured as a function of temperature. As a result, three resonances were observed: sharp and broad resonances around the Larmor frequency and a resonance split by the electric quadrupole interaction. It was found that the appearance of the resonances is similar to the case of Si host (Izumikawa et al. Hyperfine Interact. 136/137:559–605, 2001). The quadrupole coupling constant for the split resonance was deduced as ∣eqQ/h∣ = 252(3) kHz under the assumption that it has <111> axial symmetry. And furthermore, assuming that the defect atom jumps thermally between the identical defect sites, the activation energy of the jump was deduced as 0.4 ± 0.1 eV. 相似文献
49.
Saiko Sugawara Toshihiko Ito Shiori Sato Yuki Sato Kano Kasuga Ikuo Kojima Masayuki Kobayashi 《Applied biochemistry and biotechnology》2014,172(1):206-215
Fibroblast growth factor 4 (FGF4) is considered as a crucial gene for tumorigenesis in humans and the development of mammalian embryos. The secreted, mature form of human FGF4 is thought to be comprised of 175 amino acid residues (proline32 to leucine206, Pro32-Leu206). Here, we found that bacterially expressed, 6× histidine (His)-tagged human FGF4 (Pro32-Leu206) protein, referred to as HishFGF4, was unstable such as in phosphate-buffered saline. In these conditions, site-specific cleavage, including between Ser54 and Leu55, in HishFGF4 was identified. In order to generate stable human FGF4 derivatives, a 6× His-tagged human FGF4 (Leu55-Leu206), termed HishFGF4L, was expressed in Escherichia coli. HishFGF4L could be purified from the supernatant of cell lysates by heparin column chromatography. In phosphate-buffered saline, HishFGF4L was considered as sufficiently stable. HishFGF4L exerted significant mitogenic activities in mouse embryonic fibroblast Balb/c 3T3 cells. In the presence of PD173074, an FGF receptor inhibitor, the growth-stimulating activity of HishFGF4L disappeared. Taken together, we suggest that HishFGF4L is capable of promoting cell growth via an authentic FGF signaling pathway. Our study provides a simple method for the production of a bioactive human FGF4 derivative in E. coli. 相似文献
50.
Yukiko Moriizumi Hajime Fukuda Seiya Tanaka Daisuke Tanaka Kazukiyo Nagai 《Journal of polymer science. Part A, Polymer chemistry》2020,58(18):2586-2602
This study aimed to determine the solubility and temperature dependence of methanol and ethanol vapor caused by the difference in the substituents of polyhedral oligomeric silsesquioxane (POSS)-containing polymethacrylate membranes and the spacer length between the backbone and POSS backbone. Vapor sorption of methanol and ethanol was measured at 25°C, 35°C, and 45°C for three kinds of POSS-containing polymer membranes, namely, poly(methacryl isobutyl POSS), poly(methacrylate isobutyl POSS), and poly(methacryl phenyl POSS). The primary structures of the three POSS-containing polymer chains were columnar. The solubility of alcohol vapor on the POSS-containing polymer membranes followed the mechanism of solid adsorption and not the general dissolution diffusion. The sorption amount at all three temperatures was related to the surface area of the cylindrical primary structure and the solid adsorption property of the alcohol molecule of the POSS substituent. The sorption amount increased because of the large surface area and adsorption property of alcohol molecules. Although a typical glassy polymer shows exothermic mixing and a rubbery polymer displays endothermic mixing, the sample with the POSS substituent of isobutyl group exhibited an unusual behavior of endothermic mixing despite being a glassy polymer. 相似文献