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1.
This paper provides a fundamental analysis of a power supply and rectifiers for wireless power transfer using magnetic resonant coupling (MRC). MRC enables efficient wireless power transfer over middle‐range transfer distances. MRC for wireless power transfer should operate at a high frequency in the industry science medical band, such as 13.56 MHz, because the size of the transfer device decreases at higher transfer frequencies. Therefore, the output frequency of the power supply on the transmitting side should be 13.56 MHz. In addition, the rectifier on the receiving side is operated at a high frequency. This paper focuses on the reflected power in the power supply and rectifiers. Thus, the parametric design method is clarified for the power supply, including a low‐pass filter to match the output, the impedance of the power supply with the characteristic impedance of the transmission line. In addition, the effects on the rectifiers of silicon carbide and gallium nitride diodes are confirmed by performing an experiment and a loss analysis.  相似文献   
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Gas effusion spectra of fullerenes are studied. Three peaks of toluene are found in gas effusion spectra dp/dT-T. Two peaks of oxygen are found in gas effusion spectra dN/dt-T of samples kept in the air after annealing to avoid the toluene. These phenomena confirmed to be reversible are discussed by treating fullerenes as intercalated materials.  相似文献   
4.
a-Si alloy three-stacked solar cells have been studied to improve the stabilized efficiency of a-Si: H based solar cells. Based on the analysis by the individual characterization method of the component cells in stacked type cells, the a-Si :H middle cell was replaced with an a-SiGe :H cell. Furthermore, the optical confinement technology was improved to obtain a high-output current with thin i-layer thickness in the a-SiGe :H bottom cell. By this device design, the initial conversion efficiency was improved up to 12.4% and more than a 10% stabilized efficiency was obtained in a-SiC :H/a-SiGe :H/a-SiGe :H three-stacked cells. These cell characteristics were confirmed by measurements at the JQA Organization (the former JMI Institute).  相似文献   
5.
A high-performance liquid chromatographic (HPLC) separation of diacylglycerol acetates to quantitatite disaturated species of lung phosphatidylcholine (PC) was studied. The diacylglycerol acetates were applied on a reversed phase column, eluted by an isocratic solvent, acetonitrile/isopropanol/water (35:15:1, v/v/v) at a flow rate of 1 ml/min, and detected by differential refractometry (RI). This isocratic HPLC method was useful to separate disaturated species from the others of lung PC. The quantitative analysis of the molecular species separated by HPLC was studied by RI detection. Chroamtograms obtained by RI detection and radioactivity determination of diacylglycerol [3H]acetates prepared by [3H]acetic anhydride were almost identical. The RI detector responsed in the same degree for different, authentic standards of diacylglycerol acetates. The detection limit with RI detection was about 30 nmoles. Molecular species of PCs from human lung and carcinoma tissues were analyzed by this HPLC method. The contents of disaturated species were very similar to those reported previously. These results indicate that RI detection is very useful in the nmole range for the quantitative analysis among the molecular species containing disaturated species.  相似文献   
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The mechanical, electrical and thermal properties of alkaline earth metal (Mg, Ca and Sr)-doped LaCrO3 have been examined as separators in planar-type high-temperature solid oxide fuel cells. The maximum three-point bending strength at 1000°C in air was measured and found to be 186 MPa for LaCr0.9Mg0.1O3, 36 MPa for La0.9Ca0.1CrO3 and 77 MPa for La0.9Sr0.1CrO3. The La0.8Sr0.2CrO3 separator placed in both an oxidizing and a reducing environment at 1000°C showed almost the same electrical conductivities of the H2 atmosphere, and the conductivity was independent of sample thickness in the range 0.5–3.0 mm. For all the doped LaCrO3 perovskites, a difference between the thermal expansion behaviours of air and the H2 atmosphere was observed. In particular, the thermal expansion slope for the first heating cycle under the H2 atmosphere showed a marked change. The volume changes were due to the formation of oxygen defects in the perovskite structure. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   
8.
Yamamoto  M. Itoh  K. 《Electronics letters》1997,33(6):441-443
In a slot-coupled microstrip antenna with a triplate line feed, the parallel-plate mode is excited by the slot, resulting in a decrease of radiation efficiency. The authors present a technique for suppressing the parallel-plate mode in this type of the antenna. Measured results confirm the effective performance of the proposed method  相似文献   
9.
A micromachined lead zirconate titanate (PZT) force sensor for scanning force microscope (SFM) is conceptualized by its piezoelectricity. The fabrication procedure is interpreted, and mechanical characteristics of the micromachined PZT force sensors with various lengths are studied in this paper. A compact SFM is constructed by using the piezoelectric PZT sensor. A very clear image is taken by this SFM. The current study of the micromachined PZT force sensor can be considered as a breakthrough of design of SFM as well as a good example of integrated piezoelectric microdevices  相似文献   
10.
A very simple and rapid test for species identification is reported. Extracts of bloodstains were applied to a synthetic porous membrane and dried. The membrane was then quenched with glycine buffered saline containing BSA and Tween 20. A suspension of colloidal gold particles (GP) coated with rabbit antiserum to human IgG was poured onto, gently whirled and aspirated through the membrane. Spots from the human and monkey bloodstains became red, whereas those from other species of animals remained unstained. This test was completed within 3 to 4 min, and the antibody-coated GP reagent was prepared within 20 min using a very small quantity of antiserum. Cellulose acetate membranes of 0.45 microns or more in pore size were appropriate to this test.  相似文献   
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