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81.
Mamiko Hori Cécile Pagnoux Jean-François Baumard Masayuki Nogami 《Journal of Materials Science》2007,42(1):80-86
A new method is proposed to produce gold nanoparticles (GNP) by in situ reduction of a gold salt dissolved in water. The reducing
agent used is Tiron instead of the citrate anion most often mentioned in literature. The influence of various parameters has
been investigated, such as the content of Tiron with respect to that of the precursor of gold HAuCl4, or the initial pH of the solution after mixing of reactants. It is shown that Tiron also exerts a positive influence as
a dispersant, which impedes agglomeration of gold nanoparticles. The typical average size of GNP synthesized in the present
work is close to 7 nm. 相似文献
82.
83.
Grazing incidence reflection absorption Fourier transform infrared (GIRA-FTIR) spectroscopy was used to characterize the ferroelectric behavior of a thin poly(vinylidene fluoride–trifluoroethylene) P(VDF–TrFE) copolymer. The lab-built GIRA-FTIR apparatus allowed the heating and corona poling process to be carried out whilst collecting the GIRA spectra of the thin polymer film. The Curie transition from the ferroelectric to paraelectric phase was confirmed from the abrupt change in intensity of the 849 cm−1 band in the RA-FTIR spectrum. It was found that the Curie temperature dropped dramatically when the film thickness was lowered to below a certain critical value of approximately 100 nm. The switching of the CF2 dipoles in the ferroelectric crystals after applying the external electric field could be determined by monitoring the change in the 849 cm−1 band intensity. For the 600 nm thick P(VDF–TrFE) film, the switching of the dipoles appears to occur almost instantaneously, while the kinetics of dipole switching of the 75 nm thick film were significantly retarded. The repeated switchability of the CF2 dipoles upon the application of a bipolar cyclic electric field was also confirmed. The bistability of the film due to remnant polarization was also confirmed from the absorbance of the 849 cm−1 band after removing the applied voltage during corona poling. 相似文献
84.
Du Young Choi Long Mei Jin Dexian Wang Kyung Ho Row 《Korean Journal of Chemical Engineering》2005,22(3):465-469
High-performance frontal analysis (HPFA) was used for a protein binding study of isoflavones (daidzein, genistin, and genistein),
enantiomers of perillyl alcohol and S-ibuprofen to human serum albumin (HSA). The analyses were performed on a Develosil and
Inertsil 100-Diol-5 column (10 cm×4.6mm). Sodium phosphate solution (pH 7.4, ionic strength 0.17) was used as the mobile phase
at a flow rate of 1 ml/min. To ensure the drug to be eluted as a trapezoidal peak with a plateau, injection volumes were each
fixed up the zonal profile with an evident plateau appears. The unbound drug concentration was determined from a plateau height
of the plateau region after that experimental data were fitted by Scatchard equation. The binding constants (K) and total
binding affinities (nK) of drugs to HSA were calculated, respectively. 相似文献
85.
Y. K. Cheung W. G. Jin O. C. Zienkiewicz 《International journal for numerical methods in engineering》1991,32(1):63-78
The application of the Trefftz method for calculating wave forces on offshore structures is presented. Indirect and direct formulations using complete and non-singular systems of Trefftz functions for the Helmholtz equation are posed in this paper. An effective technique using different interpolation functions for the velocity potential and wave force are suggested to improve the computational accuracy of the wave force. The numerical examples show that the present method is highly efficient and accurate. 相似文献
86.
M. K. Bakhadyrkhanov O. É. Sattarov Kh. M. Iliev K. S. Ayupov Tuérdi Umaier 《Semiconductors》2005,39(7):789-791
It is experimentally ascertained that light stimulates the negative magnetoresistance observed in a high electric field in silicon doped with boron and manganese. The optimum conditions (the electric field, temperature, illumination, and resistivity of the material) for observation of the largest magnitude of negative magnetoresistance in (Si:B):Mn are determined. The dependence of the negative magnetoresistance on the concentration of compensating impurity is established. 相似文献
87.
88.
89.
90.
Nguyen An Tien I. Ya. Mittova O. V. Almjasheva S. A. Kirillova V. V. Gusarov 《Glass Physics and Chemistry》2008,34(6):756-761
Nanocrystalline LaFeO3 is prepared by the dehydration of coprecipitated lanthanum and iron(III) hydroxides. It is shown that the behavior of the samples during heating and the size distribution of LaFeO3 nanocrystals can be considerably different depending on the scheme used for coprecipitation of lanthanum and iron hydroxides; independently of the method employed for coprecipitation of the initial compounds, sintering of the samples at 950°C leads to the formation of lanthanum orthoferrite crystals up to 100 nm in size. 相似文献