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1.
Transparent conducting Zn−Sn−O films were deposited on Polypropylene adipate thin-film substrates at low temperature by r. f. magnetron sputtering. The structural, electrical and optical properties of the deposited films were investigated. All the obtained films are of amorphous structure and have a very good adhesion to the substrates. The resistivity, carrier concentration and Hall mobility of the film are 1.3×10−2 Ω·cm, 4.1×1019 cm−3 and 12.4 cm2· V−1· s−1, respectively. The transmittance of the film reaches 82%.  相似文献   

2.
Moisture is an important factor affecting the insulation properties of transformers. Due to the limitations of macroscopic experimental methods, the diffusion of water at oil–paper interface cannot be accurately measured. Therefore, molecular dynamics method was used in this work to establish oil–paper layer model of 105 atoms. Through jointly analysing the aggregation degree, diffusion coefficient, free volume as well as radial distribution function of water molecules, the diffusion mechanism of water molecules at oil–paper interface was studied. The results show that when the initial water content in paper was high, water molecules would accumulate at oil–paper interface to form the local high-water region during heating. The polarisation of the electric field strengthened the hydrogen bonding interaction between water molecules and increased the probability of occurrence of the high-water region. Meanwhile, electric field reduced the free volume and diffusion coefficient of water molecules and rendered its diffusion coefficient anisotropic. What’s more, when the electric field was combined with the temperature field, the electric field played a leading role in the diffusion of water molecules while the temperature field was less affected. Diffusion coefficients of water molecules at different temperatures from molecular dynamics simulations were well consistent with experimental results, which verified the rationality of the model.  相似文献   

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Sono-dispersion of Ni, Co and Ni–Co over Al2O3–MgO with Al/Mg ratio of 1.5 was prepared and tested for dry reforming of methane. The samples were characterized by XRD, FESEM, PSD, EDX, TEM, BET and FTIR analyses. In order to assess the effect of ultrasound irradiation, Ni–Co/Al2O3–MgO with Co content of 8% prepared via sonochemistry and impregnation methods. The sono-synthesized sample showed better textural properties and higher activity than that of impregnated one. Comparison of XRD patterns indicated that the NiO peaks became broader by increasing Co content over the support. The FESEM images displayed the particles are small and well-dispersed as a result of sonochemistry method. Also, EDX analysis demonstrated better dispersion of Ni and Co as a result of sonochemistry method in confirmation of XRD analysis. The sono-synthesized Ni–Co/Al2O3–MgO as a superior nanocatalyst with Co content of 3% illustrates much higher conversions (97.5% and 99% for CH4 and CO2 at 850 °C), yields (94% and 96% for H2 and CO at 850 °C) and 0.97 of H2/CO molar ratio in all samples using an equimolar feed ratio at 850 °C. During the 1200 min stability test, H2/CO molar ratio remained constant for the superior nanocatalyst.  相似文献   

5.
The condensation reaction involving an o-aminoaryl ketones with α-methylene ketones via the tandem addition/annulation reaction by the ionic liquid of [Hbim][BF4] (IL) as a solvent with methanol as co-solvent at room temperature under ultrasound irradiation afforded the corresponding quinolines derivatives in excellent yields. The use of ionic liquid and ultrasound, which promoted this protocol under room temperature without the requirement of any added catalyst. Quinoline derivatives are important and have a potential use as special biological drug in medicine.  相似文献   

6.
A combination of Iron-57 Mössbauer spectroscopy and magnetic susceptibility measurements are used to show that the [FeCl5 2–] and [FeCl5-(CH3OH)–2] anions (stabilized in the solid state by large quaternary cations) undergo ferromagnetic order, Tcritical6 K.  相似文献   

7.
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