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1.
Formation of the Pb(Zr,Ti)O3 solid solution in the system PbO-TiO2-ZrO2 was studied by chemical analysis and X-ray powder diffrac-tometry. Only PbTiO3 and Pb(Zr,Ti)O3 were found as reaction products. The following three elementary reactions seemed to be reasonable for the formation of the Pb(Zr,Ti)O3 phase: PbO + TiO2→ PbTiO3, PbTiO3+ PbO + ZrO2→Pb(Zr1-λTiλ)O3, and Pb(Zrl-λTiλ)O3+ PbTiO3→ Pb(Zr1-λ'Tiλ')O3 (λ<λ').  相似文献   
2.
Electric vehicles (EVs) are expected to play a leading role in the changeover from fossil fuels to clean energy. However, EVs are currently not very popular, owing to their short cruising distance and long charging time. Wireless power transfer from the infrastructure to running EVs is expected to be the solution to these problems. Electric vehicle and electrified roadway (EVER) has been proposed as a wireless power transfer system for EVs while in motion. Via‐wheel power transfer (V‐WPT) is expected to be a wireless power transfer scheme for EVER. We designed and prototyped a 1:32 scale model of a V‐WPT system that consists of an RF inverter, an electrified roadway, a rectifier, and an EV with a dc motor. The output power of the prototype RF inverter was 5.9 W and the dc–RF conversion efficiency was 36.6%. The LC matching circuits for the V‐WPT were designed with two‐port conjugate matching because S11 of the V‐WPT was intrinsically –0.06 dB. After matching, the S11 value was reduced to –21.5 dB. The power transmission efficiency of the V‐WPT system was 75%. The RF–dc conversion efficiency of the rectifier was 62%. The total efficiency of the EVER system was 24.2%.  相似文献   
3.
Titanium-containing glasses were prepared by fusion of a base glass (BaO·B2O3SiO2) and TiO2 and/or Ti2O3 in Ar. Their resistivities did not vary with melting time and temperature. Interaction of Ti4+ and Ti3+ in the glasses was deduced by spectroscopy, but the valence states in the batch compositions were preserved in the glasses, according to the chemical analysis. Glasses containing either Ti4+ or Ti3+ had very high resistivities, whereas the glass prepared by melting a mixture of a Ti4+-containing and a Ti3+-containing glass had much lower resistivity. All results confirmed the possibility of controlling the resistivity by batch composition for these glasses.  相似文献   
4.
An analogue window function circuit is realized by using switched-capacitor techniques. In order to verify the effect of this window, a novel switched-capacitor analogue discrete Fourier analyser is proposed. The window function circuit is included in this analyser as the ratios of capacitances. This switched-capacitor discrete Fourier analyser is very simple in construction, namely, only two elemental circuits based on the integral feedback capacitance circuit are connected in series. Agreement between the experimental and the theoretical values is confirmed.  相似文献   
5.
Chemiluminescence (CL) produced in beer was detected using the single photoelectron counting system. CL production did not occur in a nitrogen atmosphere but did occur in air and was dependent on incubation temperatures. It was inhibited by the addition of ascorbic acid. CL analysis should provide useful information in the study of oxidative deterioration of beer.  相似文献   
6.
Direct measurements of hypoxanthine (Hx) in fish flesh were carried out using a sardine and a grunt twice with the same fish, and the average of 10 successive measurements (from 120 sec to 480 sec after pressing the probe against fish tissue) was taken as the Hx concentration by direct measurement. Results with two nearby tissues of one sample were 42.9 ± 4.9 μM and 42.6 ± 2.6 μM for the sardine, and 639 ± 33 μM and 598 ± 29 μM for the grunt. For sardine, Hx results from this direct method did not agree well with perchloric acid extraction measurements, but they were much better for grunt.  相似文献   
7.
The adsorption properties of cobalt(II) ions have been studied on layered dihydrogen tetratitanate hydrate fibers, H2Ti4O9,?nH2O, in the temperature range from 298 to 523?K. The distribution coefficients of the adsorption of cobalt (II) ions were increased with increasing temperatures up to 367?K, but were decreased in the temperature range between 367 and 523?K. The X-ray powder diffraction patterns of the fibers indicate that the fibers hold layer structure up to 367?K, but change to low crystalline anatase or its precursor above that temperature. It is notable that the material has the capability of cobalt (II) adsorption even at 523?K, although the maximum is present at 367?K.  相似文献   
8.
ABSTRACT

Ion-exchange properties of a new type of hydrous titanium dioxide with a fibrous form, which was obtained from potassium dititanate (K2O(TiO2)2), have been studied. The pH titration curve snowed that this material behaved as a bifunctional ion-exchanger. Distribution coefficients of some divalent metal ions on this material were measured as a function of pH and the selectivity series were found to be Ba > Sr > Ca > Mg for alkaline earth metal ions and Cu > Zn > Mn > Co > Ni for divalent transition metal ions. Large separation factors were obtained between some metal ion pairs and the mutual separations such as Cu from Sr, Ca, Mg, Co and Ni, and Mg from Ba and Zn have been achieved on columns of this material.  相似文献   
9.
A fluorometric assay for lipid hydroperoxide in meats and fish was developed using pea peroxygenase, a hydroperoxide-dependent hy-droxylase. The freeze-dried microsome fraction of germinating pea seed was used as a peroxygenase source. Linear relationships between the hydroperoxide added (25 to 150 nmol) and fluorescence were observed with methyl linoleate hydroperoxide, linoleic acid hydroperoxide, triglyceride hydroperoxide, and phosphatidylcholine hydroperoxide. α-Tocopherol at levels equivalent to those in meats and fish did not affect the peroxygenase reaction. The assay was specific for hydroperoxides. The method enables determination of total lipid hy droperoxides in sample homogenates without extracting total lipids from retail meats and fish.  相似文献   
10.
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