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111.
Soo Kyung Bae Min‐Jung Kim Eon‐Jeong Shim Doo‐Yeoun Cho Ji‐Hong Shon Kwang‐Hyeon Liu Eun‐Young Kim Jae‐Gook Shin 《Biomedical chromatography : BMC》2009,23(6):568-572
A simple and rapid HPLC method using fluorescence detection was developed for determination of irbesartan in human plasma. Sample preparation was accomplished through a simple deproteinization procedure with 0.4 mL of acetonitrile containing 800 ng/mL of losartan (internal standard), and to a 0.1 mL plasma sample. Chromatographic separation was performed on a Zorbax Xclipse XDB C18 column (150 × 4.6 mm, i.d., 5 µm) at 40°C. An isocratic mobile phase, acetonitrile:0.1% formic acid (37:63, v/v), was run at a flow‐rate of 1.0 mL/min, and the column eluent was monitored using a fluorescence detector set at excitation and emission wavelengths of 250 and 370 nm, respectively. The retention times of irbesartan and losartan were 4.4 and 5.9 min, respectively. This assay was linear over a concentration range of 10–5000 ng/mL with a lower limit of quantification of 10 ng/mL. The coefficient of variation for this assay precision was less than 8.48%, and the accuracy exceeded 94.4%. The mean relative recoveries of irbesartan and losartan were 98.4 and 99.1%, respectively. This method was successfully applied for pharmacokinetic study after oral administration of irbesartan (300 mg) to 23 Korean healthy male volunteers. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
112.
Ji‐Eun Lee 《School science and mathematics》2006,106(2):98-104
This classroom scholarship report is based on the teaching experience using Davydov's mathematics curriculum, which was developed in the former Soviet Union. While “from arithmetic to algebra” is the normally accepted instructional sequence in school mathematics, Davydov's curriculum is laid out “from algebra to arithmetic,” focusing on algebraic thinking from the very beginning of the elementary grades. The purpose of this report is not to provide a definitive conclusion about which curriculum or sequence is better nor to address which instructional strategy is right in all circumstances. Rather, it is to explore how primary grade students develop their own conceptual understanding while confronting difficulties met within a specific context. This report provides actual classroom episodes from working with a group of first graders and describes dynamic interactions between the teacher and children while they discuss the use of algebraic expressions and understand the meaning behind them. 相似文献
113.
Sang Ju Lee Seung Jun Oh Eun Hye Cho Da Hye Kim Shozo Furumoto Nobuyuki Okamura Jae Seung Kim 《Journal of Radioanalytical and Nuclear Chemistry》2017,314(3):1587-1593
[18F]THK-5351, a new candidate for tau protein imaging, is based on an aryl quinoline structure. We report the full automatic synthesis using disposable cassettes under pH controlled [18F]fluorination. After the trapping of 88.5 ± 21.9 GBq of [18F]fluoride, it was eluted with potassium methansulfonate (KOMs) (pH 7.8)/K222. After drying, 3 mg of the precursor was added to 1 mL DMSO and subjected to [18F]fluorination at 110 °C for 10 min. After hydrolysis, the final product was purified by HPLC. The overall radiochemical yield was 31.9 ± 11.1% (n = 22), satisfying all quality control criteria. It was stable for up to 6 h with high radiochemical purity as 99.8 ± 0.5%. 相似文献
114.
Hooyoung Song Jooyoung Suh Eun Kyu Kim Kwang Hyeon Baik Sung-Min Hwang 《Journal of Crystal Growth》2010,312(21):3122-3126
Nonpolar (1 1–2 0) a-plane GaN films have been grown using the multi-buffer layer technique on (1–1 0 2) r-plane sapphire substrates. In order to obtain epitaxial a-plane GaN films, optimized growth condition of the multi-buffer layer was investigated using atomic force microscopy, high resolution X-ray diffraction, and transmission electron microscopy measurements. The experimental results showed that the growth conditions of nucleation layer and three-dimensional growth layer significantly affect the crystal quality of subsequently grown a-plane GaN films. At the optimized growth conditions, omega full-width at half maximum values of (11–20) X-ray rocking curve along c- and m-axes were 430 and 530 arcsec, respectively. From the results of transmission electron microscopy, it was suggested that the high crystal quality of the a-plane GaN film can be obtained from dislocation bending and annihilation by controlling of the island growth mode. 相似文献
115.
Gang Eun Kim 《Journal of Optimization Theory and Applications》2012,152(3):727-738
In this paper, we first prove the weak convergence for the Moudafi’s iterative scheme of two quasi-nonexpansive mappings. Then we prove the weak convergence for the Moudafi’s iterative scheme of quasi-nonexpansive mapping and nonexpansive mapping. Finally, we prove the strong convergence for the Moudafi’s iterative scheme of two quasi-nonexpansive mappings. Our results generalize the recent results due to Iemoto and Takahashi. 相似文献
116.
We establish C2,α-estimates for solutions of a class of quasilinear elliptic equations with free boundary and tangential derivative boundary problems. Using this regularity result we show the existence of global solutions to regular shock reflections for the unsteady transonic small disturbance (UTSD) equation. We also present Lipschitz estimates near the degenerate Dirichlet boundary (the sonic boundary) for the UTSD equation. 相似文献
117.
An autofocus technique is proposed for a three-dimensional imaging, direct-detection laser radar system that uses a Geiger-mode avalanche photodiode focal plane array (GmAPD-FPA). This technique is implemented by pointing laser pulses on a target of interest and observing its scattered photon distribution on a GmAPD-FPA. Measuring the standard deviation of the photon distribution on a GmAPD-FPA enables the best focus condition to be found. The feasibility of this technique is demonstrated experimentally by employing a 1 × 8 pixel GmAPD-FPA. It is shown that the spatial resolution improves when the GmAPD-FPA is located in the best focus position found by the autofocus technique. 相似文献
118.
Eun Jin Jun 《Tetrahedron letters》2006,47(18):3103-3106
New anthracene derivatives bearing thiourea group have been synthesized and characterized including X-ray crystallography. These chemosensors display selective ratiometric changes in their fluorescence spectra upon the addition of fluoride ion. 相似文献
119.
L. C. Bland F. Bieser R. L. Brown H. J. Crawford A. A. Derevshchikov J. L. Drachenberg J. Engelage L. Eun C. A. Gagliardi S. Heppelmann E. G. Judd V. I. Kravtsov Yu A. Matulenko A. P. Meschanin D. A. Morozov L. V. Nogach S. B. Nurushev A. Ogawa C. Perkins G. Rakness K. E. Shestermanov A. N. Vasiliev 《The European Physical Journal C - Particles and Fields》2005,43(1-4):427-435
Comparisons of particle production from high-energy ion collisions with next-to-leading order perturbative QCD calculations show good agreement down to moderate transverse momentum values. Distributions of azimuthal angle differences between coincident hadrons in these collisions support a partonic origin to the particle production, again down to moderate transverse momentum values. The rapidity dependence of inclusive and coincident particle production can therefore be used to probe parton distribution functions down to small momentum fractions where theory anticipates that parton saturation could be present. This paper describes how such experiments could be completed.Arrival of the final proofs: 27 July 2005PACS:
12.38 Qk, 13.88. + e, 24.85. + p 相似文献
120.