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101.
Yutaka Saito Yukiko Inden-Okazaki Shoko Wada-Yano Atsuko Kanetsuna Kei-Ichi Miyazaki Masaki Mifune Yoshimasa Tanaka Hideki Okuda 《Analytica chimica acta》1985
A simple and sensitive method for assay of human serum albumin (5–80 μg) is based on binding of chrome azurol S by the albumin and determination of the bound dye spectrofluorimetrically. The method is sufficiently sensitive for application to spinal fluid (20–100 μl). 相似文献
102.
Kinetic study of the annealing of fission tracks in a Fe2O3KPO3 glass containing 100 ppm of uranium
The kinetics of the annealing of fission tracks in an artificial glass were studied using an optical microscope. The annealing experiments were performed in an electric furnace at 160–230°C for 15–160 min. The measurement of the fission tracks through an optical microscope was carried out after etching the annealed tracks with 10 N NaOH aqueous solution at 40°C. All reactions were found to be of first order within the annealing temperatures. An activation energy of 0.66 eV for the annealing reaction was obtained from the Arrhenius plot of the rate constants determined at 160, 190, 210, and 230°C. 相似文献
103.
Biju V Makita Y Sonoda A Yokoyama H Baba Y Ishikawa M 《The journal of physical chemistry. B》2005,109(29):13899-13905
The formation of narrow size dispersed and nanometer size aggregates (clusters) of cadmium selenide (CdSe) quantum dots (QDs) and their temperature-sensitive photoluminescence (PL) spectral properties close to room temperature (298 K) are discussed. CdSe QDs formed stable clusters with an average diameter of approximately 27 nm in the absence of coordinating solvents. Using transmission electron microscopy (TEM) imaging, we identified the association of individual QDs with 2-5 nm diameters into clusters of uniform size. A suspension of these clusters in different solvents exhibited reversible PL intensity changes and PL spectral shifts which were correlated with temperature. Although the PL intensity of CdSe QDs encapsulated in host matrixes and the solid state showed a response to temperature under cryogenic conditions, the current work identified for the first time QD clusters showing temperature-sensitive PL intensity variations and spectral shifts at moderate temperatures above room temperature. Temperature-sensitive reversible PL changes of clusters are discussed with respect to reversible thermal trapping of electrons at inter-QD interfaces and dipole-dipole interactions in clusters. Reversible luminescence intensity variations and spectral shifts of QD clusters show the potential for developing sensors based on QD nanoscale assemblies. 相似文献
104.
Masahide Yasuda Yoshimasa Nishinaka Takumi Nakazono Takeshi Hamasaki Nobuya Nakamura Tsutomu Shiragami Chyongjin Pac Kensuke Shima 《Photochemistry and photobiology》1998,67(2):192-197
It was found that tetra-o-acyl riboflavins efficiently photosensitize the monomerization of the cis, syn-cyclobutane dimers of 1,3-dimethylthymine and 1,3-dimethyluracil in aqueous solution in the presence of such anionic surfactants as sodium dodecyl sulfate and sodium hexadecyl sulfate at concentrations higher than their critical micelle concentration, while little monomerization of the dimers was photosensitized by the flavins in the absence of the surfactants and even in the presence of cationic and nonionic surfactants. 相似文献
105.
Chihiro Moriguchi Akihiro Ohta Chikara Egami Yoshimasa Kawata Susumu Terakawa Masaaki Tsuchimori Osamu Watanabe 《Optical Review》2006,13(4):215-217
We present an analysis of the properties of an imaging based on a near-field recording technique in comparison with simulation
results. In the system, the optical field distributions localized near the specimens are recorded as the surface topographic
distributions of a photosensitive film. It is possible to observe both soft and moving specimens, because the system does
not require a scanning probe to obtain the observed image. The imaging properties are evaluated using fine structures of paramecium,
and we demonstrate that it is possible to observe minute differences of refractive indices. 相似文献
106.
Yoshimasa Yamamoto Patjaree Suksawad Nanthaporn Pukkate Tatsuya Horimai Osamu Wakisaka Seiichi Kawahara 《Journal of polymer science. Part A, Polymer chemistry》2010,48(11):2418-2424
Formation of photoreactive nanomatrix structure was investigated by graft‐copolymerization of an inclusion complex of 1,9‐nonandiol dimethacrylate (NDMA) with β‐cyclodextrin (β‐CD) onto natural rubber particle using potassium persulfate (KPS), tert‐butyl hydroperoxide/tetraethylenepentamine (TBHPO/TEPA), cumene hydroperoxide/tetraethylenepentamine (CHPO/TEPA), and benzoyl peroxide (BPO) as an initiator. The graft copolymer was characterized by 1H NMR and FTIR after coagulation. The conversion of NDMA and the amount of residual methacryloyl group were found to be 58.5 w/w % and 1.81 w/w %, respectively, under the suitable condition of the graft‐copolymerization. The morphology of the film specimen, prepared from the graft copolymer, was observed by transmission electron microscopy (TEM) after staining the film with OsO4. Natural rubber particle of about 1.0 μm in diameter was dispersed in poly(NDMA) matrix of about 10 nm in thickness. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2418–2424, 2010 相似文献
107.
Yoichi Ogata Takeshi Mogi Yutaka Makita 《Journal of Polymer Science.Polymer Physics》2010,48(5):588-594
Solution property of hydrogenated polystyrene‐b‐poly(ethylene/butylene)‐b‐polystyrene triblock copolymer (SEBS copolymer) was studied by using static light scattering and dynamic light scattering for cyclohexane and N‐methylpyrrolidone (NMP) solutions. From the values of dimensionless parameters ρ, defined as the ratio of radius of gyration 〈S2〉1/2 to hydrodynamic radius RH, and solubility parameters, SEBS copolymer proved to exist as single chain close to random coil in nonpolar cyclohexane, whereas aggregate into the core‐shell micelle consisting of poly(ethylene/butylene) (PEB) core surrounded by PS shell in polar NMP. The core‐shell micelle formed in NMP is composed of 65 polymer chains, having three times larger average chain density (d = 0.12 g cm?3) than a single polymer chain (d = 0.04 g cm?3) in cyclohexane. The comparison with the aggregation behaviors in other solvents demonstrated that the aggregate compactness of the copolymer depended largely on solvent polarity, resulting in formation of the highly dense PEB core (Rc = 4.5 nm) and the thick PS shell (ΔR = 22.9 nm) in high‐polar NMP. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 588–594, 2010 相似文献
108.
109.
Inami Wataru Fukuta Masahiro Masuda Yuriko Nawa Yasunori Ono Atsushi Lin Sheng Kawata Yoshimasa Terakawa Susumu 《Optical Review》2015,22(2):354-358
Optical Review - A plastic scintillator film for use in an electron beam excitation-assisted (EXA) optical microscope is characterized. The thin film scatters an incident electron beam weakly and... 相似文献
110.
Haino T Kobayashi M Fukazawa Y 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(12):3310-3319
The synthesis and spectroscopic characterization of a cavitand-based coordination capsule 14 BF4 of nanometer dimensions is described. Encapsulation studies of large aromatic guests as well as aliphatic guests were performed by using 1H NMR spectroscopy in [D1]chloroform. In addition to the computational analysis of the shape and geometry of the capsule, an experimental approach to estimate the interior size of the cavity is discussed. The cavity provides a highly rigid binding space in which molecules with lengths of approximately 14 A can be selectively accommodated. The rigid cavity distinguished slight structural differences in the flexible alkyl-chain guests as well as the rigid aromatic guests. The detailed thermodynamic studies revealed that not only CH-pi interactions between the methyl groups on the guest termini and the aromatic cavity walls, but also desolvation of the inner cavity play a key role in the guest encapsulation. The cavity preferentially selected the hydrogen-bonded heterodimers of a mixture of two or three carboxylic acids 18-20. The chiral capsule encapsulated a chiral guest to show diastereoselection. 相似文献