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991.
T. Ohishi S. Maekawa T. Ishikawa D. Kamoto 《Journal of Sol-Gel Science and Technology》1997,8(1-3):511-515
A new technique for preparing anti-reflection/anti-static thin films for CRTs at low temperature has been developed. Double-layered
films of SiO2/SnO2 were formed on a CRT panel surface by the sol-gel method using photoirradiation. The new method makes it possible to reduce
heat treatment temperature (°C) by almost 50% and treatment time to approximately 33% of the conventional levels. 相似文献
992.
993.
利用磁场诱导的微粒运动即磁泳对磁响应性粒子进行精细分离,是近年来发展起来的选择性分离细胞和高分子量核酸的有效技术。本文在阐明磁泳分离原理的基础上,介绍了磁泳分离的分流薄层分级技术、四极磁场流动分离技术和微芯片上的自由流磁泳分离技术的装置构造、工作原理及其在生物分离分析中的应用。 相似文献
994.
Silver halide (AgX) microcrystal was used as template to synthesize hollow polyelectrolyte capsules. These hollow capsules were characterized by laser light scattering (LLS) used to measure the size of the capsules in solution. The ratio of hydrodynamic radius (Rh) from dynamic LLS to the radius of gyration (Rg) from static LLS is almost unity, revealing that the entities are hollow in solution. The results suggest that the LLS method can be regarded as a good complement to the confocal laser scanning microscopy (CLSM) method for the characterization of small hollow capsules, and it possesses the advantage of not needing fluorescence labeling. 相似文献
995.
Slow pyrolysis of walnut shell which is a cheap and abundantly available solid waste was carried out using thermogravimetric
analysis. The effects of raw material heating rate on the pyrolysis properties and kinetic parameters were investigated. A
two-step consecutive reaction model were used to simulate the pyrolysis process. The kinetic parameters were established by
using the pattern search method. Comparison between experimental data and the model prediction indicated that the two-step
consecutive reaction model can better describe the slow pyrolysis of walnut shell as the formation of an intermediate during
the pyrolysis process was taken into account. 相似文献
996.
997.
998.
Paraskevas D. Tzanavaras Demetrius G. Themelis Anastasios Economou Georgios Theodoridis 《Mikrochimica acta》2003,142(1-2):55-62
Two new simple and rapid methods are reported for the accurate and precise spectrophotometric determination of captopril
(CPL) using flow (FI) and sequential injection (SI) analysis. The methods are based on the fast oxidation of CPL by Fe(III).
The produced Fe(II) reacts with 2,2′-dipyridyl-2-pyridylhydrazone (DPPH) in acidic medium to form a colored complex which
is monitored spectrophotometrically at 535 nm. Both methods allow the determination of the analyte up to 1000 mg L−1 at a sampling rate of 120 and 60 injections per hour for FI and SI, respectively. The methods are very precise [s
r=0.8 and 1.2% at 500 mg L−1 CPL (n=12) for FI and SI, respectively] and the 3σ detection limits (c
L=4.0 and 7.0 mg L1, respectively) are quite satisfactory. Their application to a variety of anti-hypertensive commercial pharmaceutical formulations
showed excellent results (relative errors, e
r, < ± 1.6% in all cases compared to an official HPLC method), while common pharmaceutical excipients were found not to interfere.
Recovery experiments further verified the accuracy of the developed methods, as the percent recoveries were in the range of
98.1–102.5%.
Author for correspondence. E-mail: themelis@chem.auth.gr
Received May 9, 2002; accepted January 8, 2003
Published online May 5, 2003 相似文献
999.
在Na_2O-1.6-C_6H_(14)N_2-SiO_2-TiO_2-H_2O体系中首次用快速动态法和静态法合成了TiZSM-48型分子筛,考察了两种合成方法的晶化动力学。利用XRD、IR、XPS、SEM、DRS、TG-DTA等测试手段对TiZSM-48型分子筛进行了表征,结果表明,Ti进入了分子筛骨架,动态法合成比静态法合成快得多,且样品的晶粒较小。热分析表明,两种方法合成的样品热稳定性均较好。 相似文献
1000.
目视催化褪色计时法测定超痕量钒的研究 总被引:6,自引:1,他引:6
本文基于在酸性介质中钒(V)催化溴酸钾氧化酸性铬蓝K褪色的新指示反应,建立了一个催化褪色计时法测定超痕量钒的新方法。在体系中引入活化剂抗坏血酸,灵敏度达2×10~(-12)ng/ml,测定范围在0.0l~3.0ng/ml,同时探讨了反应机理。确立了反应速率方程,方法简便经济,已用于天然水中痕量钒的测定。 相似文献