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排序方式: 共有1431条查询结果,搜索用时 390 毫秒
921.
Z. Zhou F. Jin H. Enomoto T. Moriya H. Higashigima 《Journal of Materials Science》2006,41(5):1501-1507
A continuous flow reaction system designed for producing acetic acid by wet oxidation (WO) of biomass with the maximum treatment
capacity of 1 kg/h of dry biomass was developed. Experimental runs with rice hulls and starch were conducted at reaction temperatures
between 300–320°C, for time of 2 and 3 min, with oxygen supplies between 70 and 100%, and at pressures between 10 and 30 MPa.
The influence of each of these parameters was evaluated. 相似文献
922.
Nakamura A. Moriya H. Terano T. Kosaka H. Hashiguchi A. Nomoto K. Fujiwara I. Kobayashi T. Oda T. 《Electron Devices, IEEE Transactions on》2004,51(6):895-900
This paper describes the narrow and nonspreading distribution of threshold voltage in metal-oxide-nitride-oxide semiconductor (MONOS) memory cell array with Fowler-Nordheim (F-N) channel write operation and direct/F-N tunneling erase operation as a single transistor structure. We fabricated a 4-Mbit MONOS memory test chip using 0.25-/spl mu/m technology. The gate length of the memory cell was shrunk to 0.18 /spl mu/m. The distribution of threshold voltage for many operations were evaluated. The range of threshold voltage distribution is small, within 0.5 V in 12-14 V for programming and -8.5 to -9 V for erasing. It was also narrow for program/erase cycles up to 10/sup 4/ and after exposure to temperatures of 300/spl deg/C for 17 h and 150/spl deg/C for 304 h. These characteristics of narrow Vth distribution represent advantages of the MONOS memory device both for nonverify operation in program/erase mode and for low supply voltage operation in read mode. Another advantage is that no anomalous leak cell or tail bit is evident in the data retention result, demonstrating high reliability. The MONOS memory device is a promising candidate for use in cheaper and more scalable gate length fabrication processes compared with floating gate for highly reliable embedded applications. 相似文献
923.
924.
T Kinoshita H Shirasawa Y Shino K Shimizu H Moriya B Simizu 《Canadian Metallurgical Quarterly》1996,42(1-2):119-125
Signs of acute respiratory distress were reported in moulting grey seals (Halichoerus grypus) hauled out on Lady's Holm, Shetland, following the Braer oil spill in January, 1993. Behavioural observations carried out between 16 January and 13 February 1993 showed that the proportion of animals exhibiting a discharge of nasal mucus was significantly higher than the proportion at a control site in the north (Papa Stour). The proportion of animals affected on Lady's Holm increased for up to one month following the spill. However, the time lag between exposure and peak response was approximately 30 days, longer than may be expected for an acute effect. The proportion of non-specific signs of respiratory distress in unexposed Shetland seals was assessed from observations made between 16 January and 25 January 1994. Symptoms similar to those seen in 1993 were also reported during this period, but the proportion of affected animals was higher in 1993. Symptoms were not observed at a grey seal moult site on the east coast of England in March 1993 and 1994. Grey seals moulting in Shetland during the time of the oil spill may have been acutely affected by exposure to hydrocarbons, but without sufficient baseline data on the occurrence of respiratory distress in grey seals it is difficult to determine the proportion attributable to other causes. 相似文献
925.
Fukashi Ueda Keiju Matsui Kazuo Tsuboi Masahiro Asao Tadashi Kobayashi Makoto Watanabe 《Electrical Engineering in Japan》1996,117(5):57-69
The neutral-point-clamped (NPC) PWM inverters have many advantages such as the ability to operate the motor with nearly sinusoidal current waveforms. For this reason, in larger-capacity inverter systems, NPC PWM inverters using the GTOs, etc., have also been put into practical use because of great advantages to large-capacity ac motor drives such as lower ripple currents and higher output voltages. With the spread of applications, still larger-capacity inverters also are expected. However, since the capacities of such switching devices are insufficient, a certain technique and controlling method are proposed for the parallel connections of NPC inverters. The output voltage waveforms of the proposed inverter have certain voltage levels, and thus it is anticipated that it will be difficult to analyze the output harmonics. For such waveforms of output voltage and current-sharing reactor, a frequency analysis approach is described whose results are verified by experiments. 相似文献
926.
Yoshiki Susaki Osamu Nakamura Fumio Kawachi Masayoshi Yamaoka Takeshi Nishimura Tadashi Kuriyama 《Electrical Engineering in Japan》1996,117(1):85-95
An improved method of degradation diagnosis for medium-size distribution transformers is described. The proposed method uses refined criteria of degradation for specific application for 200- to 1000-kVA range transformer diagnostics. The new criteria were established with a 95 percent confidence limit of data after extensive case studies focusing on the relationship between the amounts of CO and CO2 generated in transformer oil and the length of operating time of the transformer. Another feature of this diagnostic technique is the provision of a capability to estimate the thermal history of the insulation material by examining the amounts of certain trace products of decomposition present in the transformer oil. For this purpose, a thermal history discriminant chart was devised by application of a canonical discriminant analysis method. 相似文献
927.
Toshiyuki Kawashima Tadashi Kanabe Osamu Matsumoto Ryo Yasuhara Hiroyuki Furukawa Masahiro Miyamoto Takashi Sekine Takashi Kurita Hirofumi Kan Masanobu Yamanaka Masahiro Nakatsuka Yasukazu Izawa 《Electrical Engineering in Japan》2006,155(2):27-35
The diode‐pumped slab laser for inertial fusion energy driver has been demonstrated, which produces the 1053‐nm output energy of 10 J at 10 Hz. The glass slab laser amplifier has been pumped by quasi‐CW 290‐kW AlGaAs laser‐diode arrays at 803 nm. The optical system can compensate for thermal effects by use of zigzag optical propagation, image‐relayed telescope, and 45° Faraday rotator. The output energy of 10.6 J at 1 Hz with the optical‐to‐optical conversion efficiency of 19.9% has been successfully obtained. Also, the 10‐Hz operation has been performed with an output energy of 5.1 J. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 155(2): 27–35, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20288 相似文献
928.
In 3 experiments, lists of 12 Kanji words were rapidly presented in the same position, and participants reported a red target word embedded in green distractor words. Two lists were used: same and different category. A tendency toward category priming was found at longer durations. Frequency of target localization indicated that participants familiar with Kanji had a greater tendency to report the word immediately preceding the target. These pretarget intrusion errors dominated the posttarget intrusion errors, when the luminance of red and green stimuli were equated (Experiment 2), and when the response was recall (Experiments 1 and 2) or recognition (Experiment 3). In contrast, participants unfamiliar with Kanji made posttarget intrusion errors as frequently as pretarget intrusion errors (Experiment 3), suggesting that knowledge of Kanji influences the integration of color and form codes in visual information processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
929.
A Saito M Sakamoto A Saito M Ohmichi Y Hiraga K Kikuchi Y Ohsaki N Sasaki H Matsumoto T Suda M Tsuzino Y Hirai H Inoue M Yoshida T Mouri H Kobayashi S Chiba T Ito K Moriya T Bando K Takeuchi Y Tanifuji K Shirato Y Tanno M Nakashima 《Canadian Metallurgical Quarterly》1996,49(2):144-174
To objectively evaluate the efficacy, safety and usefulness of the newly developed penem oral antibiotic, ritipenem acoxil (RIPM-AC), against bacterial pneumonia, we conducted a multi-center double-blind comparative study using cefotiam hexetil (CTM-HE) as the control drug. Both RIPM-AC and CTM-HE were orally administered at 200 mg t.i.d. for 14 days, in principle. The results were as follows: The total number of patients enrolled in this trial was 208, of which 152 cases (RIPM-AC group: 73, CTM-HE group: 79) were evaluable for clinical efficacy. 1. The clinical efficacy rates (excellent + good) were 91.8% (67/73) in the RIPM-AC group and 94.9% (75/79) in the CMT-HE group. There was no significant difference between the two groups, and the clinical equivalency of RIPM-AC to CTM-HE was demonstrated. 2. In the patients enrolled in the evaluation of clinical efficacy, the eradication rates of the causative organisms were 84.6% (22/26) in the RIPM-AC group and 91.7% (22/24) in the CTM-HE group, with no significant difference between the two groups. 3. Side effects were noted in 9 cases (9.6%) of the RIPM-AC group and 5 cases (4.9%) of the CTM-HE group. Abnormal laboratory test findings were observed in 23 cases (26.7%) of the RIPM-AC group and 15 cases (15.6%) of the CTM-HE group. There was no significant differences between the two groups in the incidence of side effects nor of abnormal laboratory test findings. In the safety evaluation, RIPM-AC was judged to be safe in 64 cases (68.1%) and CTM-HE in 82 cases (80.4%), with no significant difference. 4. The usefulness rates (markedly useful+useful) were 86.5% (64/74) in the RIPM-AC group and 92.5% (74/80) in the CTM-HE group. There was no significant difference between the two groups. Since RIPM-AC showed clinical efficacy similar to those of CTM-HE and posed no particular safety problems, it is expected to be a useful antibiotic for the treatment of bacterial pneumonia. 相似文献
930.