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21.
Tetsuo Miyazaki Shigeru Nagasaka Isao Maeda Takuro Matsumoto Shinji Koyama Seiji Kodama Masami Watanabe 《Radiation Physics and Chemistry》1996,47(6):817-819
Emission from high-energy-electron-irradiated golden hamster embryo (GHE) cells has been studied over the temperature range 12–300 K both by a one-shot-single-photon-counting method and by photocurrent measurements with an oscilloscope. Emission from the irradiated phosphate buffered saline (PBS) also has been studied. The emission spectra from PBS at 12 and 77 K show a maximum around 330 and 380 nm, respectively, which are the same spectra as those from irradiated pure H2O. The emission from irradiated GHE consists of the new band at 480 nm in addition to the emission from H2O. The 480 nm emission is observed at the temperature range of 12–300 K, though the emission at 300 K is much lower than that at low temperature. The 480 nm emission is ascribed to the transition from excited organic substances in GHE cells. The intensity of 480 nm emission at 300 K increases linearly with increasing irradiation-dose in the range of 11–600 Gy. 相似文献
22.
Kojima Kunihiko Miyazaki Mitsuharu Mizukami Fujio Maeda Kazuyuki 《Journal of Sol-Gel Science and Technology》1997,8(1-3):77-81
The structure of iron oxide was controlled by regulating the hydrolytic polymerization of aquo iron complexes with organic
polydentate ligands such as diols. Iron oxides were prepared by calcining the precursor polymers obtained from iron nitrate
nonahydrate and diols. When the diols were 1,2-pentanediol, 1,2-hexanediol and 1,2-octanediol, α-Fe2O3 with corundum structure appeared exclusively or as the main crystalline phase, in spite of the amount of diol used and the
calcination temperature. In the case of 1,2-decanediol and 1,2-dodecanediol, when five moles of the diols were used to one
mole of iron nitrate and the calcination temperatures were below 400°C, ψ-Fe2O3 with spinel structure appeared as the main phase and, when less than five moles of the diols were used, α-Fe2O3 appeared exclusively or as the main phase, irrespective of the calcination temperature. This tendency was also observed in
thin films. Thus, a transparent magnetic film composed of γ-Fe2O3 could be prepared by applying a benzene solution of the iron polymer, obtained with 5 equivalents of 1,2-decanediol, on quartz
and calcining the gel film at 350°C. 相似文献
23.
Tatsuro Ouchi Hidetake Miyazaki Hidetoshi Arimura Fumitaka Tasaka Atsushi Hamada Yuichi Ohya 《Journal of polymer science. Part A, Polymer chemistry》2002,40(10):1426-1432
Amphiphilic AB‐type diblock copolymers composed of hydrophobic poly(L ‐lactide) (PLA) segments and hydrophilic poly(glycolic acid lysine) [poly(Glc‐Lys)] segments with amino side‐chain groups self‐associated to form PLA‐based polymeric micelles with amino surfaces in an aqueous solution. The average diameter of the loose core–shell polymeric micelles for poly(Glc‐Lys) [number‐average molecular weight (Mn) = 1240]‐b‐PLA (Mn = 7000) obtained by a dimethyl sulfoxide/water dialysis method was estimated to be about 50 nm in water by dynamic light scattering measurements. The size and shape of the obtained polymeric micelles were further observed with transmission electron microscopy and atomic force microscopy. To investigate the possibility of applying the obtained PLA‐based polymeric micelles as bioabsorbable vehicles for hydrophobic drugs, we tested the entrapment of drugs in poly(Glc‐Lys) (Mn = 1240)‐b‐PLA (Mn = 7000) micelles and their release with doxorubicin as a hydrophobic drug. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1426–1432, 2002 相似文献
24.
Takaaki Suishu Seiichiro Tsuru Tetsuro Shimo Kenichi Somekawa 《Journal of heterocyclic chemistry》1997,34(3):1005-1011
Regioselective photocycloadditions of 2-pyridones ( 1 ) with 2,4-pentadienoates ( 3 ) were analysed and compared with the reactions with propenoate ( 2 ), and origins of the different regioselectivities were inferred from frontier molecular orbital properties by the use of PM3-CI method. Direct photoreactions of 1 with 3 being α,β,γ,δ-unsaturated carboxylates gave four types of regio-selective [2+2]cycloadducts, 3-β:4-α-4, 5, 3-δ:4-γ-6,7,5-δ: 6-γ-8, 9 and 5-δ:6-γ-[2+2]cycloadducts 10,11. Sensitized photoreactions of 1 with 3 did not occur, and fluorescence of 1 was weakly quenched by 3. Otherwise, main cycloadducts in the sensitized reactions of 1 with 2 have been obtained as 5-α:6-β-[2+2]cycloadducts, which were different from main 3-β:4-α-[2+2]cycloadducts of the direct reactions, and these site-and regio-selectivities were inferred from the different frontier molecular orbital coefficients at the. 3-and 6-positions of 1 for the triplet and singlet states. Formations of 4–7 were also interpreted by both effects of frontier orbital HSOMO-LUMO interactions and of the electrostatic interaction between 1 and 3. The other site-and regioselective adducts 8–11 were inferred to be formed by the electrostatic interactions similar to 2-pyridone photodimerization. 相似文献
25.
The stability constants of the Mn(2+), Fe(2+), Co(2+), Ni(2+), Cu(2+) and Zn(2+) complexes with four acids of the type HOOCCH(2)O(CH(2)CH(2)O)(n) CH(2)COOH (n = 0-3) are reported. For n = 0 the constants are in the Irving-Williams order, but not for n = 1-3. 相似文献
26.
Kiyoshi Tanemura Yoko Nishida Tsuneo Suzuki Koko Satsumabayashi Takaaki Horaguchi 《Journal of heterocyclic chemistry》1997,34(2):457-460
1,3-Dithianes 1 , 1,3-dithiolanes 2 , and diphenyl dithioacetals 3 derived from cinnamaldehydes reacted with 2,3-dichloro-5,6-dicyano-p-benzoquinone in aqueous solvents to give benzaldehydes 4 . Hydride transfer from 1–3 to 2,3-dichloro-5,6-dicyano-p-benzoquinone followed by hydrolysis and oxidative carbon-carbon bond cleavage would produce benzaldehydes 4 . 相似文献
27.
S Kishino Z S Di M Sugawara K Iseki K Miyazaki S Kakinoki A Homura A Kitabatake 《Journal of chromatography. A》1992,582(1-2):246-248
A rapid and simple method for the determination of alpha 1-acid glycoprotein (AAG) in serum was developed by using an anion-exchange column for clean-up of serum and a hydroxyapatite column for high-performance liquid chromatography (HPLC). A good correlation was observed between this HPLC method and the conventional radial immunodiffusion method. The method may also be used to determine the AAG concentration in the serum of experimental animals. 相似文献
28.
Toru Sakaki Takaaki Harada Yohko Kawahara Seiji Shinkai 《Journal of inclusion phenomena and macrocyclic chemistry》1994,17(4):377-392
A criterion for the selection of a suitable plasticizer for calix[n]arene-based ion-selective electrodes is discussed. The cation selectivity of plasticized membranes without the ligand was first measured as a reference. The membranes can be roughly classified into two groups. The first group shows cation selectivity in the order Cs++>K+>Na+>Li+. The membranes in the second group are made of phosphorus plasticizers, which show a selectivity in the reverse order. The plasticizers in the first group featured a linear relationship between the dipole moment of the plasticizer (calculated by a PM3 method) and the ratio of cesium selectivity to lithium selectivity. The linear relationship supports the view that the polar membrane which includes a soft plasticizer with a large dipole moment shows selectivity for Cs+, whereas the nonpolar membrane including the soft plasticizer with the small dipole moment shows much lower selectivity for Cs+. Next, 2-fluorphenyl-2-nitrophenyl ether (FPNPE) which showed the highest Cs+ selectivity and tris(2-ethylhexyl)phosphate (TEHP) which showed the highest Li+ selectivity were mixed in an appropriate ratio to make membranes with a different affinity for hard ions. The metal selectivities of several crown-based and calixarene-based ionophores were examined in these membranes. Although a few exceptions exist, the polar soft membrane is favorable when the interfering metal ion is hard, whereas the hard membrane is favorable when the interfering metal ion is soft. 相似文献
29.
The effect of an ultrasound (1 MHz) on transdermal absorption of indomethacin from an ointment was studied in rats. Ultrasound energy was supplied for between 5 and 20 min at a range of intensities (0.25, 0.5, 0.75, and 1 W cm-2), energy levels commonly used for therapeutic purposes. For evaluating skin penetration of indomethacin, the change of plasma concentration was measured. The pronounced effect of ultrasound on the transdermal absorption of indomethacin was observed at all ultrasound energy levels studied. The intensity and the time of application were found to play an important role in the transdermal phonophoretic delivery system of indomethacin; 0.75 W cm-2 appeared to be the most effective intensity in improving the transdermal absorption of indomethacin, while the 10 min ultrasound treatment was the most effective. Although the highest penetration was observed at an intensity of 0.75 W cm-2, 0.5 W cm-2 was preferred because intensities of less than 0.5 W cm-2 of ultrasound for 10 min did not result in any significant skin temperature rise nor did it have any destructive effect on rat skin. Progressively more skin damage was noted as the intensity and the time of application of ultrasound increased. When used at a proper intensity and time of application, ultrasound appears to be a safe technique for enhancing the passage of various drug molecules through human skin. 相似文献
30.
A study was made of the use of calcium oxide as a catalyst at a temperature of 400–700° for the dehy-drocyclization of four primary arylamines: 2-aminobiphenyl, 1-aminotriphenylene (5c) , 2-phenoxyaniline, and N-(2-aminophenyl)pyrrole. Maximal yields of cyclized products isolated were 53% (carbazole), 52% (4H-naphtho[1,4-def]carbazole), 18% (phenoxazine), and 0%, respectively. Comparison is made with reported cyclizations of the corresponding nitro and azido starting materials. In one case, treatment of I-nitrotriphenylene with triethyl phosphite produced mainly diethyl N-(1-triphenylenyl)phosphoramidate (51%). Mono- and hemihydrochlorides of 5c are described. A mechanism for the catalyzed dehydrocy-clization is proposed. 相似文献