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排序方式: 共有1319条查询结果,搜索用时 15 毫秒
141.
Y. Ono Y. Miyazaki S. Yabuuchi H. KageshimaM. Nagase A. FujiwaraE. Ohta 《Thin solid films》2011,519(24):8505-8508
Magnetic properties of manganese (Mn) nanosilicide embedded in thin silicon-on-insulator (SOI) layers are investigated. Mn nanosilicide formed by Mn+ ion implantation into a thin SOI layer followed by a thermal annealing at 600-900 °C shows soft ferromagnetism or superparamagnetism at 5 K. A monotonic decrease of the saturation magnetization is observed with increasing temperature for post implantation annealing and consequently with increasing mean particle size of nanosilicide. In addition, the magnetization is found to be enhanced when the Si surrounding the Mn nanosilicide is selectively removed. These results indicate that the magnetic moment indeed arises from the nanosilicide and is sensitive to the interface conditions. 相似文献
142.
Youichi Ogo Kenji Nomura Hiromichi Ohta Masahiro Hirano Hideo Hosono 《Thin solid films》2006,496(1):64-69
A reactive solid-phase epitaxy (R-SPE) method combines deposition of a thick amorphous or polycrystalline layer with a desired chemical composition and post-deposition solid-phase epitaxial growth. The solid-phase epitaxial growth is invoked by thermal annealing with an assistance of a sacrificial layer working as an epitaxial template. Thereby it enables us to grow high-quality epitaxial films of complex oxides whose epitaxial films are not grown by conventional high-temperature growth techniques. It was reported that 2-nm-thick ZnO layers worked as template for growing InGaO3(ZnO)m (m = integer) epitaxial films. The present study extended the R-SPE technique to growth of various complex oxides with chemical compositions of RAO3(MO)m and to use of various epitaxial template layers. We found that mono oxide epitaxial layers such as In2O3 and Ga2O3 work as template layers as well. Alternatively, a ZnO epitaxial layer is also applicable to ZnO-free compounds. The films obtained were grown heteroepitaxially on YSZ(111) and single-crystalline when the fabrication conditions are optimized. 相似文献
143.
Infrared transmission spectra of C60 multilayers on thin Pd films deposited onto surface-oxidized Si(100) and hydrogen-terminated Si(111) substrates are reported. In both cases, the spectra in the 1500–1100 cm−1 region exhibited bands at 1444, 1429, and 1182 cm−1 due, respectively, to the Ag (2), T1u (4), and T1u (3) modes. The appearance of the Ag (2) mode, which is originally infrared inactive (Raman active), reveals electron transfer from the metal to chemisorbed C60. Indeed, increasing the thickness of C60, the Ag (2) mode intensity saturated more rapidly than the T1u (4) and T1u (3) modes. The originally infrared active T1u (4) and T1u (3) modes were enhanced in intensity depending upon the Pd thickness. Actually, while both substrates gave nearly the same magnitude of enhancement, the optimum Pd thickness was smaller on the hydrogen-terminated surface than on the surface-oxidized surface. On the other hand, the Ag (2) mode was less intense on the hydrogen-terminated surface than on the oxidized surface, suggestive of a shortage of chemisorbed C60 and thus pointing out the importance of the metal film morphology. Indeed, Pd films deposited on the two substrates gave rise to quite different AFM images. We also show that, regardless of the substrate, the Ag (2) mode is an order of magnitude smaller than for Ag deposition, though no remarkable intensity differences were observed with respect to the T1u (4) and T1u (3) modes. 相似文献
144.
Yuji Fukaishi Yoshihiro Ohta Kohji Higuchi Eiji Takegami Satoshi Tomioka Kosin Chamnongthai 《Artificial Life and Robotics》2012,17(1):1-6
A robust DC?CDC converter which can covers extensive load change and also input voltage changes with one controller is needed. Then the demand to suppress output voltage change becomes still severer. We propose an approximate 2-degree-of-freedom (2DOF) digital controller which realized start-up response and dynamic load response independently. The controller makes a control bandwidth wider, and at the same time makes variations of the output voltage small at sudden changes of a load and an input voltage. In this paper, a new approximate 2DOF digital control system with additional zeros is proposed. Using the additional zeros, the second-order differential transfer characteristics between equivalent disturbances and a output voltage are realized. Therefore, the new controller makes variations of the output voltage smaller and the sudden changes of the load and the input voltage. This controller is actually implement on a DSP and is connected to the DC?CDC converter. Experimental results demonstrate that this type of digital controller can satisfy given severe specifications with low frequency sampling. 相似文献
145.
Iida M. Kuroda N. Otsuka H. Hirose M. Yamasaki Y. Ohta K. Shimakawa K. Nakabayashi T. Yamauchi H. Sano T. Gyohten T. Maruta M. Yamazaki A. Morishita F. Dosaka K. Takeuchi M. Arimoto K. 《Solid-State Circuits, IEEE Journal of》2005,40(11):2296-2304
A 16 Mb embedded DRAM macro in a fully CMOS logic compatible 90 nm process with a low noise core architecture and a high-accuracy post-fabrication tuning scheme has been developed. Based on the proposed techniques, 61% improvement of the sensing accuracy is realized. Even with the smallest 5 fF/cell capacitance, a 322 MHz random-cycle access while 32 ms data retention time which contributes to save the data retention power down to 60 /spl mu/W are achieved. 相似文献
146.
Tatsuya Mutakamihigashi Yoshito Kuroishi Hideki Ueno 《Electrical Engineering in Japan》2015,192(3):19-26
We have investigated the characteristics of radiated electromagnetic (EM) waves from positive and negative partial discharges (PD) in epoxy resin and cross‐linked polyethylene. We found that there is a correlation among the EM level from PD, the positive PD current, and electrical trees. Therefore, the growth of an electrical tree produces a lot of positive PD. We have also investigated the characteristics of the frequency region of EM waves from PD in air, insulating oil, and liquid epoxy in addition to the above insulators. EM waves were detected in the frequency region of 40 MHz to 300 MHz from positive and negative PD in epoxy resin and cross‐linked polyethylene. EM waves were also detected in the frequency region of 40 MHz to 150 MHz from positive and negative PD in air. In the case of insulating oil and liquid epoxy, EM waves were detected in the frequency regions of 40 MHz to 150 MHz from positive PD, and 40 MHz to 250 MHz from negative PD. The frequency region differed depending on the material and the discharge polarity. Our investigation indicates that the cause is differences in electric field strength at the time of PD occurrence. 相似文献
147.
Kagawa K. Isakari K. Furumiya T. Uehara A. Tokuda T. Ohta J. Nunoshita M. 《Electronics letters》2003,39(5):419-421
A newly designed pulse frequency modulation photosensor for use in retinal prosthesis is proposed and demonstrated. The pixel converts the intensity of incident light into biphasic current pulses at frequencies suitable for the electrical stimulation of retinal neurons. Experimental results showed that the device was sensitive over a dynamic range of input light of about 120 dB, and that photosensitivity could be varied from 0 dB to around -40 dB. 相似文献
148.
This case study was designed to examine the self-defined health needs of families in one urban Western Australian community. We conducted 157 family interviews to examine the relationship between family sociodemographic variables and patterns of use of health services, which included services used within the previous 12 months, and what the family needed and wanted from these services. Questions covered perceptions of health, family health concerns and the role of the family health guardian. Quantitative analysis included frequencies, cross-tabulations, chi-squared tests and multiple regression analysis. Open-ended responses were categorised and analysed for common themes. Approximately 80 per cent of participants had used one or more health services during the previous 12 months and, despite 35.9 per cent of families having at least one family member with a long-standing illness, disability or infirmity, most (82.1 per cent) considered the family healthy. The correlational analysis revealed several associations. Predictably, younger persons reported higher health ratings and older persons had more health concerns. Larger families reported better perceived levels of health. Higher utilisation rates were recorded for families with children, who tended to use the general practitioner for general care and medication, whereas one-parent families used hospital and specialist care more often, and 98.7 per cent reported satisfaction with services. What they needed and wanted from their health service providers was 'full disclosure' and 'not being talked down to', and for specialists especially to be approachable and impart information simply and honestly. 相似文献
149.
S Ohue K Kohno K Kusunoki K Sadamoto S Ohta T Ueda S Sakaki 《Canadian Metallurgical Quarterly》1998,40(8):536-540
Although magnetic resonance angiography (MRA) is accepted for showing chronic intracranial stenotic or occlusive lesions, the method has not been practically examined in patients with acute cerebral ischaemia. We carried out three-dimensional time-of-flight MRA in six patients with acute ischaemia treated by local thrombolysis, and compared the findings with those of digital subtraction angiography (DSA). In all patients, MRA before thrombolysis clearly demonstrated the occluded arteries, which corresponded precisely to those shown by DSA. In four patients with complete recanalisation of the occluded vessels after thrombolysis, the recanalisation could be demonstrated by postoperative MRA. In one patient with reocclusion of the recanalised artery, repeat MRA also demonstrated the reocclusion, confirmed by DSA. These results suggest that MRA may be helpful for noninvasive investigation before and after thrombolysis. 相似文献
150.
H Horino T Mimura K Kagechika M Ohta H Kubo M Kitagawa 《Canadian Metallurgical Quarterly》1998,46(4):602-609
A series of 3,4-dihydro-3-hydroxy-4-[(5-oxo-3,4-diazabicyclo[4.1.0]hept- 2-en-2-yl)oxy]-2H-1-benzopyrans and their analogues were synthesized and evaluated on potassium channel opening and hypotensive activities. Compound (-)-13B with a (4-methyl-5-oxo-3,4-diazabicyclo[4.1.0]hept-2-en-2-yl)oxy group for the 4-position of the benzopyran ring was 3 times as potent as EMD 57283 (II), the lead compound, in hypotensive activity. The results would demonstrate that 5-oxo-3,4-diazabicyclo[4.1.0]hept-2-en-2-yloxy moieties are effective as the substituents at the 4-position of benzopyran-type potassium channel openers. 相似文献