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排序方式: 共有846条查询结果,搜索用时 15 毫秒
841.
Asakura R Isobe T Kurokawa K Aizawa H Ohkubo M 《Analytical and bioanalytical chemistry》2006,386(6):1641-1647
YAG:Ce3+ nanoparticles 9.5 ± 1.2 nm in diameter have been synthesized from aluminium isopropoxide and acetates of yttrium and cerium
in 1,4-butanediol (1,4-BD) by autoclave treatment at 300 °C for 2 h. After replacing 1,4-BD by ultrapure water, NH2 groups were introduced on the surface of YAG:Ce3+ nanoparticles by addition of 3-aminopropyltrimethoxysilane then biotinylation with sulfo-NHS-LC-biotin. We demonstrated that
avidin immobilized beads are tagged by biotinylated YAG:Ce3+ nanoparticles by the selective avidin-biotin interaction, furnishing a green fluorescent image on excitation with blue light.
This result indicates that YAG:Ce3+ nanoparticle phosphors have much potential in biological applications. 相似文献
842.
Free energy of micelle formation has been evaluated for spherical sodium dodecyl sulfate (SDS) in water by a thermodynamic integration method combined with a series of large-scale molecular dynamics calculations following the chemical species model. In particular, free energy change delta mu(n+1)0 with respect to the addition of one surfactant molecule to the spherical micelle of size n was obtained as a function of n. The free energy profile showed a minimum followed by a maximum, which corresponds to a peak in the size distribution. The calculated peak size n = 57 near its critical micelle concentration is in good agreement with the experimental averaged aggregation number n = 55-75 of the SDS micelle. The distribution showed a rather sharp peak, indicating that the size is almost a monodisperse one. The size is likely to be insensitive to the total concentration of the surfactant. 相似文献
843.
Isobe H Hattori Y Hayano T Kanoh H Yamamoto K Kaneko K 《Journal of colloid and interface science》2006,295(2):482-489
Attempts to prepare macroporous silica particles and metal-compound-nanoparticle-embedded silica microspheres were carried out using reactions between silicon tetrachloride and ultrasonic generating microdroplets including metal (Na, K, Al, Ni, Ti, Pt) compounds. Samples were collected by dry and wet processes. In the case of using nickel and aluminum compounds, acid-treated samples were also prepared. The obtained samples were characterized by scanning electron microscopy, X-ray fluorescence spectroscopy, powder X-ray diffractometry, mercury porosimetry, and the nitrogen adsorption method. The macroporous silica particles were prepared by removing the salt crystals, such as NaCl and KCl, formed in the silica frame. For acid-resistant metals, platinum- and titanium-compound nanoparticles are easily embedded in silica microspheres using these metal-compound solutions. For acid-soluble metals, aluminum- and nickel-compound-nanoparticle-embedded silicas were prepared by applying neutralization of the collection water. Micropores and mesopores were produced in wet-process samples. Acid treatment induced the increase of micropore volumes. 相似文献
844.
Yoshio Okamoto Shigeki Habaue Yutaka Isobe Yoshikatsu Suito 《Macromolecular Symposia》2003,195(1):75-80
The radical polymerization of various (meth)acrylamides in the presence of Lewis acids such as Yb(OTf)3 and Y(OTf)3 was carried out. The polymerization with Lewis acids led to highly isotactic polymers, while the polymers synthesized without Lewis acids were atactic or syndiotactic. The dependence of the polymer properties on the tacticity was also demonstrated. 相似文献
845.
Dr. Koki Ikemoto Kanato Takahashi Prof. Dr. Takeaki Ozawa Prof. Dr. Hiroyuki Isobe 《Angewandte Chemie (International ed. in English)》2023,62(14):e202219059
“How do we decide the stoichiometry of host–guest complexes?” This question has long been answered by the Job plot since its first report in 1928. However, as the Job plot was claimed to be misleading in 2016, the question became an open question again and called for renewed investigations. An information-theoretic approach, called Akaike's information criterion, is introduced in this study to select the best model of host–guest complexes, which can rank the models with weight of evidence. A few test cases with unique cylindrical hosts were examined to demonstrate the applicability of the information-theoretic method. Consequently, reasonable views over the thermodynamic behaviors of dumbbell-and-cylinder complexes were obtained. Akaike's information criterion can be a useful and superior alternative to statistical null hypothesis testing, which was proposed as a remedy in place of the Job plot. 相似文献
846.
Yukio Nagasaki Noriyuki Yamazaki Ken-Ichiro Deguchi Masao Kato 《Macromolecular rapid communications》1996,17(1):51-58
Several types of poly(silamine)s were prepared and their structure-characteristics relationships were investigated. When a phenyl ring in the organosilyl unit and/or a cyclic structure in the amino unit was introduced, the glass transition temperatures were increased significantly in order to increase film formability. From the thermogravimetric analysis of the poly(silamine)s, it was found that the thermal decomposition of poly(silamine)s starts at ca. 380–400°C. On electron-beam irradiation of the poly(silamine) films, degradation of the polymer took place. On the basis of these results, poly(silamine)s can be one of the candidates for new positive-type polymeric resists. 相似文献