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101.
102.
Y. Ishii S. Saito S. Ohnishi 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1987,7(3):289-292
Bonding properties of sodium-cluster dimers, (X 4)2 and (X 8)2, whereX n is a jellium sphere corresponding to a cluster ofn atoms, were investigated by the linear-combination-of-jellium-orbitals method with local-spin-density-functional approximation. The stability ofn=8 clusters, observed in the experiment, is discussed in relation to the binding properties of dimers. We have found that (1) the (X 4)2 bonding has a covalent character, which makes theX 8 formation favorable, and (2)X 8 has an inert property because the force between jellium spheres in (X 8)2 is due to a weak dispersion force. 相似文献
103.
104.
Kawaguchi M Ito R Honda H Endo N Okanouchi N Saito K Seto Y Nakazawa H 《Journal of chromatography. A》2008,1206(2):196-199
A simple and highly sensitive method called stir bar sorptive extraction (SBSE) and thermal desorption (TD)-gas chromatography-mass spectrometry (GC-MS), which is used for the determination of trace amounts of 5-chloro-2-(2,4-dichlorophenoxy)phenol (triclosan) in river water samples, is described. A stir bar coated with polydimethylsiloxane (PDMS) is added to a 10mL water sample and stirring is carried out for 120min at room temperature (25 degrees C) in a vial. Then, the PDMS stir bar is subjected to TD-GC-MS. The detection limit of triclosan is 5ngL(-1) (ppt). The method shows linearity over the calibration range (0.02-20mugL(-1)) and the correlation coefficient is higher than 0.997 for triclosan standard solution. The recovery of triclosan in river water samples ranges from 91.9 to 108.3% (RSD: 4.0-7.0%). This simple, accurate, sensitive, and selective analytical method may be used in the determination of trace amounts of triclosan in river water samples. 相似文献
105.
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Total synthesis of the proposed structure 2 for phomopsin B was achieved by using an intramolecular olefin metathesis as a key step. The spectral data, however, did not match with those of the natural product reported. Re-examination of the reported NMR data led to the structural revision of phomopsin B to known dothiorelone A 18. The R configuration of dothiorelone A was determined by total synthesis through a cross-metathesis with a chiral olefin 19. 相似文献
107.
Quanling Yang Shuji Fujisawa Tsuguyuki Saito Akira Isogai 《Cellulose (London, England)》2012,19(3):695-703
Mechanical, thermal and oxygen barrier properties of regenerated cellulose films prepared from aqueous cellulose/alkali/urea
solutions can be markedly improved by controlling the drying conditions of the films. By pre-pressing followed by vacuum drying
under compression, the tensile strength, Young’s modulus, coefficient of thermal expansion and oxygen permeability of the
dried films reached 263 MPa, 7.3 GPa, 10.3 ppm K−1 and 0.0007 ml μm m−2 day−1 kPa−1, respectively. Thus, films produced in this way show the highest performance of regenerated cellulose films with no orientation
of cellulose chains reported to date. These improved properties are accompanied by a clear increase in cellulose II crystallinity
from 50 to 62% during pre-pressing/press-vacuum drying process. At the same time, the film density increased from 1.45 to
1.57 g cm−3, and the moisture content under equilibrium conditions decreased from 14.1 to 9.8%. Hence, the aqueous alkali/urea solvent
system has potential applications in producing new and environmentally friendly cellulose films with high performances through
control of the drying conditions. 相似文献
108.
109.
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Tae-Ho Kim Masakazu Saito Masaya Matsuoka Shinya Tsukada Kiyohisa Wada Masakazu Anpo 《Research on Chemical Intermediates》2010,36(5):453-461
It was found that the photoelectrochemical performance and photocatalytic activity of rod-type TiO2 electrodes were affected by various post-calcination treatments, for example, calcination in NH3 or under vacuum. Post-calcination treatment in NH3 at 773 K was particularly effective in increasing the photoelectrochemical performance and photocatalytic activity of rod-type TiO2 electrodes. A unique photoelectrochemical circuit was constructed by connecting a rod-type TiO2 electrode to a Pt electrode through a silicon solar cell in which the negative bias was applied on the rod-type TiO2 electrode. It was found that the photoelectrochemical circuit can effectively oxidize ethanethiol in water into CO2. 相似文献