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91.
M. Kambara K. Miyake K. Murata T. Izumi Y. Shiohara T. Umeda 《Physica C: Superconductivity and its Applications》2000,330(3-4):191-202
Crystal growth of the melt-textured bulk Nd1+xBa2−xCu3O6+d (Nd123) superconducting oxides was investigated by employing isothermal undercooling solidification with hot-seeding in air. From the relationship between growth length and holding time, the Nd123 crystal was found to have almost stopped growing after a certain growth period, while the growth length increased proportionally to the holding time at an early stage of the crystal growth. As a result of quantitative analysis for the Nd123 crystal of which solidification was terminated, the distribution of the Nd/Ba substitution was observed to decrease in the Nd123 single crystal matrix from the seed crystal to the edge of the Nd123 crystals. Also, the substitution content at the edge of the Nd123 crystal, which corresponds to that at the final stage of the crystal growth, was found to be in good agreement with the minimum substitution of the Nd123 solid solution phase in the equilibrium phase diagram at this process temperature. These compositional changes could be explained using the equilibrium phase diagram as associated with the solid solution formation, which is responsible for the non-steady state solidification of the Nd123 crystals even for the isothermal undercooling processing. 相似文献
92.
Tomohiro Narukawa Takayoshi Kuroiwa Izumi Narushima Koichi Chiba 《Analytical sciences》2008,24(3):355-360
The sensitivity of graphite furnace atomic absorption spectrometry (GFAAS) to arsenobetaine (AB) was 1.3-times higher than to inorganic As. In order to understand the mechanism underlying this observation, the atomization processes for both chemical species were investigated in terms of the enthalpy change (DeltaH) during the atomization process in GFAAS. The enthalpy change of AB was slightly lower than that of inorganic As, which suggested that AB was atomized more efficiently than was inorganic As. Moreover, it was observed that some co-existing organic materials enhanced the analytical sensitivity of inorganic As. The sensitivity difference between inorganic As and AB depended upon the mechanisms of their atomization processes. 相似文献
93.
Minoru Ishikura Machiko Kamada Izumi Oda Tsukasa Ohta Masanao Terashima 《Journal of heterocyclic chemistry》1987,24(2):377-386
The reaction of various lithium tributylheteroarylborates with allylic bromides in the presence of copper(I) cyanide furnished the regioselective allylation at the heteroaryl ring. 相似文献
94.
This paper is concerned with the theoretical treatment of the steady-state thermoelastic problem of a functionally graded cylindrical panel due to nonuniform heat supply in the circumferential direction. The thermal and thermoelastic constants of the cylindrical panel are expressed as power functions of the radial coordinate. We obtain the exact solution for the two-dimensional temperature change in a steady state, and thermal stresses of a simple supported cylindrical panel under the state of plane strain. Some numerical results are shown in figures and tables. Furthermore, the influence of the nonhomogeneity of the material, the radius ratio and the span angle upon the temperature change, displacements and stresses is investigated. 相似文献
95.
Y.F. Zhang M. Izumi Y.J. Li M. Murakami T. Gao Y.S. Liu P.L. Li 《Physica C: Superconductivity and its Applications》2011,471(21-22):840-842
Single domain superconductor GdBa2Cu3O7?δ bulks with variable additions of (ZnO + ZrO2 + SnO2) nano-particles was prepared in air by using top seed melt-textured growth process. The effect of nano-particle additions on superconductivity properties has been investigated. An enhancement of the critical current JC in low and intermediate field at 77 K and trapped field was discovered by the additions of the nano-particles. At the same time, the superconductor transition temperature, TC, slightly decreases from 93.5 K to 91.5 K. The experimental results show that the accumulation of the nano-particle inclusions may improve JC of the specimens. 相似文献
96.
Shuzo Izumi 《代数通讯》2013,41(12):3885-3889
The definition of stabilizer and orbit for Hopf algebra action is given, and a duality theorem on stabilizer is proved. 相似文献
97.
An immobilized urease reactor can be used with ion chromatography for the simultaneous determination of urea, and sodium, potassium and ammonium ions. The conversion of urea to ammonium ion was found to be 76.5%. The calibration graph for urea was linear over the range 1 × 10?5?1 × 10?3 M (RSD 3%). The method was applied to human urine and a chemical fertilizer. 相似文献
98.
Tachi T Hase T Okamoto Y Kaji N Arima T Matsumoto H Kondo M Tokeshi M Hasegawa Y Baba Y 《Analytical and bioanalytical chemistry》2011,401(7):2301-2305
Microchip analysis is a promising method for therapeutic drug monitoring. This led us to evaluate a microchip-based fluorescence
polarization immunoassay (FPIA) system for point-of-care testing on patients being treated with theophylline. The sera were
collected from 20 patients being treated with theophylline. Fluorescence polarization was measured on the microchip and theophylline
concentrations in serum were obtained. Regression analysis of the correlations was done between the results given by the microchip-based
FPIA and the conventional cloned enzyme donor immunoassay (CEDIA), and between the results given by the microchip-based FPIA
and the conventional particle-enhanced turbidimetric inhibition immunoassay (PETINIA). We successfully carried out a quantitative
analysis of theophylline in serum at values near its therapeutic range in 65 s. The results obtained by the microchip-based
FPIA correlated well with CEDIA and PETINIA results; the correlation coefficients (R
2) were 0.986 and 0.989, respectively. The FPIA system is a simple and rapid method for point-of-care testing of drugs in serum,
and its accuracy is the same as the conventional CEDIA and PETINIA. It is essential to use real samples from patients and
to confirm good correlations with conventional methods for a study on the realization of microchip. 相似文献
99.
In the presence of palladium salts, oxidation of 2-nitrostyrenes 1 with nitrous acid alkyl esters 2 resulted in the formation of 2-nitrophenylacetaldehyde dialkyl acetals 3. Reductive cyclization of the acetals 3 with iron powder in acetic acid afforded indoles 5 in good yield. 相似文献
100.
Ryoichi Chiba Masaaki Izumi Yoshihiro Sugano 《Archive of Applied Mechanics (Ingenieur Archiv)》2008,78(1):61-74
Forced convection heat transfer in a non-Newtonian fluid flow inside a pipe whose external surface is subjected to non-axisymmetric
heat loads is investigated analytically. Fully developed laminar velocity distributions obtained by a power-law fluid rheology
model are used, and viscous dissipation is taken into account. The effect of axial heat conduction is considered negligible.
The physical properties are assumed to be constant. We consider that the smooth change in the velocity distribution inside
the pipe is piecewise constant. The theoretical analysis of the heat transfer is performed by using an integral transform
technique – Vodicka’s method. An important feature of this approach is that it permits an arbitrary distribution of the surrounding
medium temperature and an arbitrary velocity distribution of the fluid. This technique is verified by a comparison with the
existing results. The effects of the Brinkman number and rheological properties on the distribution of the local Nusselt number
are shown. 相似文献