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1.
2.
Takashi Itoh Hitoe Habuchi Shoji Nitta Shuichi Nonomura 《Fullerenes, Nanotubes and Carbon Nanostructures》1994,2(2):181-187
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
3.
K. Nomoto H. Saitoh A. Chida H. Sannomiya M. Itoh Y. Yamamoto 《Solar Energy Materials & Solar Cells》1994,34(1-4)
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
4.
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
5.
6.
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
7.
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
8.
Manabu Iguchi Tsuneo Kondoh Keiji Nakajima 《Metallurgical and Materials Transactions B》1997,28(4):605-612
The establishment time of gas-liquid two-phase flows in a cylindrical bath agitated by bottom gas injection through a central
single-hole bottom nozzle was investigated. Because the turbulence intensity in the bath was comparable to or larger than
the unity, the conventional definition of the flow establishment time based on the history of mean velocity was not suitable
for the present case. In fact, it was difficult to determine the flow establishment time based on the well-known 90 or 99
pct criterion for the mean velocity. Accordingly, two methods of determining the flow establishment time by focusing on the
turbulence components instead of the mean velocity components were proposed. Velocity measurements were made with a two-channel
laser Doppler velocimeter. The flow establishment time was correlated as a function of gas flow rate. Close agreement was
obtained by the two methods. 相似文献
9.
Chengkuo Lee Itoh T. Suga T. 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1996,43(4):553-559
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.