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61.
Yoshitaka Takezawa Noriaki Taketani Seikichi Tanno Shuichi Ohara 《Journal of Polymer Science.Polymer Physics》1992,30(8):879-885
We have studied simple empirical equations to estimate light absorption loss αv due to harmonics of molecular vibrations of transparent amorphous polymers used in plastic optical fibers (POFs). In the visible region, absorption involves two losses. One is αv, and the other is the electronic transition absorption loss, αe. Of the two, αv is considerably larger than αe in the wavelength region used for optical communication with POFs. We have clarified relationships between chemical structure of repeat units of polymers and αv. We find that αv is proportional to the concentration of specific chemical bonds (C? H, N? H, and Obond;H bonds) in the polymer solid, and we propose empirical equations to estimate αv from the polymer density and the chemical structure of the repeat unit. These equations are used to estimate αv of several polymers [i.e., poly(methyl methacrylate), polystyrene, and polycarbonate]. The estimated values are nearly equal to the experimental or reference values. Furthermore, to minimize the attenuation in the POF, we conclude that the POF core polymer should have no N? H, O? H, or aliphatic C? H bonds in its repeat unit. 相似文献
62.
T Muto T Morishita S Iida J Yamazaki R Aoki Y Kawamura I Okuzumi T Ohara M Moriki K Hirata 《Radioisotopes》1986,35(3):122-126
Eighteen outpatients with chronic renal failure undergoing hemodialysis (HD) were studied. Immediately before and after HD, the left and right ventricular function measured by electrocardiogram gated radionuclide ventriculography (RNV). By HD, body weight changed 58.6 +/- 7.50 kg to 57.2 +/- 6.80 kg and BUN level changed 67.9 +/- 29.00 mg/dl to 37.1 +/- 18.96 mg/dl and creatinine level changed 11.3 +/- 3.90 mg/dl to 6.8 +/- 2.48 mg/dl. Before HD, cardiac output was 8.08 +/- 1.50 l/min and cardiac index was 5.00 +/- 0.87 l/(min m2). Left ventricular function improved (LVEF changed 60.4 +/- 6.85% to 64.2 +/- 8.7%, LVEF/LVET changed 0.237 +/- 0.048%/ms to 0.254 +/- 0.021%/ms) between before and after HD, but there was not significant difference. Right ventricular function improved (RVEF changed 41.2 +/- 8.00% to 50.0 +/- 11.96, RVEF/RVET changed 0.167 +/- 0.028%/ms to 0.209 +/- 0.059%/ms) between before and after HD, and there was significant difference (p less than 0.05). 相似文献
63.
Summary The adsorptive stripping voltammetric behaviour of Arsenazo III, Eriochrome Black T, 4-(2-pyridylazo) resorcinol, Mordante Blue 9 and their uranyl complexes has been investigated in detail. All compounds and complexes adsorb on the static mercury drop electrode. Results are presented and the limitations of the methods are discussed. 相似文献
64.
Hirata KS Inoue K Ishida T Kajita T Kihara K Nakahata M Nakamura K Ohara S Sato N Suzuki Y Totsuka Y Yaginuma Y Mori M Oyama Y Suzuki A Takahashi K Yamada M Koshiba M Nishijima K Suda T Tajima T Miyano K Miyata H Takei H Fukuda Y Kodera E Nagashima Y Takita M Kaneyuki K Tanimori T Beier EW Feldscher LR Frank ED Frati W Kim SB Mann AK Newcomer FM Van Berg R Zhang W 《Physical review D: Particles and fields》1991,44(8):2241-2260
65.
66.
Liquid chromatography–mass spectrometry (LC–MS) is a powerful tool for analysis of drugs and their metabolites. We used a column-switching system in combination with atmospheric pressure chemical ionization LC–MS (LC–APCI–MS) for the determination of theophylline and its metabolites in biological samples. The separation was carried out on a reversed-phase column using methanol–20 mM ammonium acetate as a mobile phase at a flow-rate of 1 ml/min in 30 min. In the mass spectrum, the molecular ions of these drugs and metabolites were clearly observed as base peaks. This method is sufficiently sensitive and accurate for the pharmacokinetic studies of these drugs. 相似文献
67.
Selma Giorgio Edlaine Linares Margareth de L. Capurro Antonio G. de Bianchi Ohara Augusto 《Photochemistry and photobiology》1996,63(6):750-754
Peroxynitrite, the potent oxidant formed by the fast reaction between nitric oxide and superoxide anion, has been suggested to be the reactive intermediate responsible for some of the pathologies associated with an overproduction of nitric oxide. In this report, we demonstrate that both nitric oxide and peroxynitrite are formed during infection of the susceptible mouse strain, BALBk, with Leishmania amazonensis. Nitric oxide was detected as the nitrosyl hemoglobin complex by EPR analysis of blood drawn from mice at 35 , 64 and 148 days of infection. The levels of nitrosyl hemoglobin complex increased with disease evolution, which in the murine model used is characterized by skin lesions, ulceration and visceral-ization of the parasites. Peroxynitrite formation was inferred from immunoreaction of homogenates obtained from footpad lesions in the late stages of the infection with anti-nitrotyrosine antibody; homogenates from parasites drawn from the lesions were also immunoreactive, although to a lesser extent. Analysis of protein homogenates by gel electrophoresis and western blots suggests that peroxynitrite may degrade proteins in vivo, in addition to nitrating them. The results demonstrate that peroxynitrite is formed during murine leishmaniasis and may play a role in the aggravation of the disease. 相似文献
68.
K. Ohara 《Colloid and polymer science》1981,259(10):981-983
Summary Thermally stimulated depolarization currents were investigated for films obtained from supernatant layer of mixed solutions ofi- ands-PMMA ini/s weight ratio of 1/1 and 1/2. The results showed that the degree of stereocomplex formation is not uniform: the mixed solutions contain the insoluble and the soluble stereocomplex aggregates and in some case the residual (free)i-PMMA. The stereocomplex is formed ini/s weight ratio of 1/2. 相似文献
69.
70.
Tetsuro Yamashita Shigeo Ohara Isao Sakamoto 《Physica C: Superconductivity and its Applications》2011,471(23-24):1655-1659
We have grown high purity single crystals of Ce2CoIn8 using the self-flux technique, and have investigated its transport, thermal, and magnetic properties, including the anisotropic features. Single crystals of Ce2CoIn8 were grown in the lower temperature region to avoid the formation of un-wanted phases such as CeCoIn5 and CeIn3 impurities. The results of the structural and physical measurements imply that the present single crystals have high purity. The electrical resistivity and specific heat measurements demonstrate that Ce2CoIn8 has a superconducting ground state with a distinct non-Fermi liquid character. This indicates that the superconductivity in Ce2CoIn8 arises out of the verge of the underlying quantum critical instability mediated by the antiferromagnetic correlations. Additionally, we investigate the crystalline electric field (CEF) energy scheme based on the temperature dependence of the specific heat and the anisotropic features in the susceptibility. We propose one of the CEF level schemes calculated on the basis of the CEF model that the first and second CEF states are located at Δ1 = 82 K and Δ2 = 102 K above the ground state doublet, respectively. 相似文献