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101.
[3]Rotaxane containing two Pd centers in the cyclic compounds catalyzes a Mizoroki-Heck reaction of substrates with two iodophenyl groups with bisacrylate. Formation of the cyclic products is enhanced by the rotaxane catalyst more smoothly than Pd(OAc)(2). 相似文献
102.
Itoh A Saitoh T Tani K Uchigaki M Sugimoto Y Yamada J Nakajima H Ohshiro H Sun S Tanahashi T 《Chemical & pharmaceutical bulletin》2011,59(8):947-951
From the embryos of the seeds of Nelumbo nucifera, three bisbenzylisoquinoline alkaloids, nelumboferine and nelumborines A and B, were isolated along with four known compounds, neferine, liensinine, isoliensinine and anisic acid. The structures of the new alkaloids were determined mainly by spectroscopic methods. 相似文献
103.
104.
Naren G Nishida I Shimada Y Tsuji Y Bai S Okaue Y Yokoyama T 《Journal of colloid and interface science》2011,353(1):331-334
This study elucidates the effect of zinc (Zn), which is an anticorrosive water additive, on the formation of silica scales from cooling water. In these experiments, the silica scales were analyzed by EPMA, and the results indicate that Zn is sorbed into the silica scales during formation. Measurements of the solubility of Zn(OH)(2) at various concentrations of silicic acid demonstrate that Zn is present as a silicato complex of Zn (SCZ) in cooling water. From adsorption experiments of the SCZ on silica and alumina, which are major components of the silica scales, it can be concluded that the SCZ accelerates the formation of silica scales from cooling water. 相似文献
105.
Yutaka Maniwa Yoshinori Kumazawa Yumi Saito Hideki Tou Hiromichi Kataura Hiroyoshi Ishii 《Molecular Crystals and Liquid Crystals》2013,570(1):671-676
Abstract X-ray diffraction (XRD) and electrical resistance measurement on single-walled carbon nan-otube (SWNT) samples prepared by the arc-discharge method are reported. The XRD profile of heat-treated sample indicated that air (oxygen, and/or nitrogen and/or water) can be condensed inside the SWNTs. We also found that the electrical resistance of SWNT soot is significantly affected by exposing to the oxygen gas and humid air. 相似文献
106.
Ground state conformation for all possible geometrical isomers of hedycaryol was estimated by the molecular mechanics calculations. All isomers are indicated to exist in more than two conformations and the parallel conformation (TC or TT) is most stable for all isomers. 相似文献
107.
Harano Azuchi Shimada Koji Okubo Tatsuya Sadakata Masayoshi 《Journal of nanoparticle research》2002,4(3):215-219
Titanium dioxide ultrafine particles (UFPs) are produced by pulsed laser ablation of titanium or titanium dioxide (anatase and rutile) rods in an atmosphere of He or O2/He mixture. The collected UFPs on cellulose membrane filters at the exit of the ablation chamber are analyzed by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The TiO2 particles produced are composed of very small particles (diameter: 10–50nm) that are completely anatase, irrespective of the rod material, and relatively large particles (diameter: 100nm–1m) that are a mixture of anatase and rutile. The large particles consist of the direct strip-off fragments coming from the rod surface. The particles obtained from the laser ablation on TiO2 rods in an atmosphere of He contains gray particles that are supposed to be amorphous TiO2 (x < 2). In the presence of O2 in the ablation chamber, these oxygen defects in amorphous TiO2 are stabilized and anatase UFPs are formed. These results suggest that the crystal phase of the products can be controlled by adjusting the rod material and the gases used in the ablation process. 相似文献
108.
Mitsumasa Taguchi Grard Baldacchino Satoshi Kurashima Atsushi Kimura Yumi Sugo Yosuke Katsumura Koichi Hirota 《Radiation Physics and Chemistry》2009,78(12):1169-1174
This article reports a highly sensitive transient absorbance measurement system using pulsed energetic ions. The ions were pulsed by a beam chopper, which was synchronized with the cyclotron, and accelerated to the desired energy around 18 MeV/u. H, He, C and Ne ions can be used for the transient absorption measurement. The optical system can measure an absorbance smaller than 1.0×10−4 in the wavelength range of 400–740 nm. 相似文献
109.
The utility of 4-(4-nitrophenyl)-1,2,4-triazoline-3,5-dione (NPTAD) as a derivatization reagent in the analysis of 25-hydroxyvitamin D3 [25(OH)D3] using liquid chromatography/electron capture atmospheric pressure chemical ionization-mass spectrometry (LC/ECAPCI-MS) was examined. The derivatives of 25(OH)D3 with NPTAD underwent electron capture in the APCI source in the negative-ion mode and provided 30-fold higher sensitivity compared to an intact compound. This derivatization-LC/ECAPCI-MS method was applied to a plasma 25-hydroxyvitamin D3 assay, and gave satisfactory results in sensitivity, specificity, measurable range and throughput of the analysis. 相似文献
110.
Nobuki Kashihara Heru Setyawan Manabu Shimada Yutaka Hayashi Chan Soo Kim Kikuo Okuyama Sugeng Winardi 《Journal of nanoparticle research》2006,8(3-4):395-403
Sine-wave modulated rf plasma has been used to control particle generation and growth in a plasma-enhanced chemical vapor deposition of silicon dioxide thin films using TEOS/O2. The density and the size of particles generated in the plasma are greatly reduced when the plasma is modulated with sine-wave modulation at low modulation frequency (<1000 Hz). In addition, particle contamination on the films is significantly reduced also for nanoparticles, and the film growth rates at the range of modulation frequencies where particle generation are greatly reduced do not decrease appreciably. Compared to its counterpart pulse-wave modulation plasma, the sine-wave modulation plasma has demonstrated a better performance in terms of reduction of particle generation and film contamination, and of film growth rate. Thus, the sine-wave modulation plasma has shown as a promising method to be applied in the production of thin film with a high deposition rate and a low particle contamination. 相似文献