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991.
Kazumi Kato Desheng Fu Kiyotaka Tanaka Kazuyuki Suzuki Tatsuo Kimura Kaori Nishizawa Takeshi Miki 《International Journal of Applied Ceramic Technology》2005,2(1):64-72
We used a Ca–Bi–Ti complex alkoxide, in which metal–oxygen bonding was confirmed by spectroscopic analysis, to deposit CaBi4 Ti4 O15 (CBTi144) thin films in various configurations. The phase transition of non-ferroelectric pyrochlore to ferroelectric perovskite in the complex-alkoxy-derived CBTi144 thin films was found to depend on the Pt bottom electrodes. Matching of the atomic arrangement to the Ca–Bi–Ti–O thin films was predominant rather than the strain and crystallinity of the bottom electrode. The thin films crystallized at 650°C on (111)-oriented Pt showed random orientation and ferroelectric P – V hysteresis loops. The endurance property was excellent against a number of switchings. For this reason, CBTi144 thin films would be expected to be excellent for application to ferroelectric random access memories (FeRAM). Polar-axis-oriented CBTi144 films were fabricated on Pt foils using the complex metal alkoxide solution. The 500-nm-thick film had a columnar structure comprising well-developed grains. The a / b -axis orientation of the ferroelectric films is considered to be associated with the preferred orientation of Pt foil. The film showed improved ferro- and piezoelectric properties. The P r , E c , and d 33 values were enhanced to become twice those of CBTi144 thin films with random orientation. These polar-axis-oriented CBTi144 films are eminently useful in devices as Pb-free piezoelectric materials. 相似文献
992.
In the present work, we report on the synthesis and characterization of poly(vinylidene fluoride) (PVDF) with N‐isopropylacrylamide (NIPAAM) polymer side chains from molecular graft copolymerization in solution. The copolymer can be readily cast into temperature‐sensitive microfiltration (MF) membranes by the phase inversion technique. The copolymer approach to membrane fabrication allows a much better control of the physicochemical nature of the membrane pores through the variation in graft concentration, membrane casting temperature and concentration of the membrane casting solution.
993.
The behavior of solid particles suspended in the freeboard of a 12 cm i.d. fluidized bed was studied using FCC particles of which the weight-mean diameter was 65 – 68 μm. The height of the freeboard was 180 cm, and the superficial gas velocity was changed from 15 to 50 cm s?1.The weight-mean diameter and holdup of solid particles in the freeboard below the TDH vary with the axial position and the gas velocity. The lateral distribution of the solids holdup measured by a capacitance probe is almost flat in the region of r ? 5 cm, but the relative pulse frequency detected by a fiber optic probe indicates that the solids holdup increases greatly in the immediate vicinity of the column wall. The flow patterns of solid particles were measured by a fiber optic probe and a thermal response probe. The steady internal circulation of solid particles is formed in the freeboard below the TDH, and the circulating solids flow rate is much larger than the net entrainment rate of solid particles. 相似文献
994.
995.
We had already made a report on outcome of schizophrenia (1986). The patients, 129 typical schizophrenia, were continuously observed over 30 years in the Kawagoe Dojinkai Hospital. Recently, we again evaluated their prognoses according to the same criteria as adopted in the first report, and divided them into the following five groups. [symbol: see text]: completely remitted group (21 persons, 16.3%), [symbol: see text]: almost remitted cases now holding jobs (23 persons, 17.8%), [symbol: see text]: Slightly remitted group showing good adjustment at home or hospital (41 persons, 31.8%), [symbol: see text]: maladjusted cases always showing an unfavorable condition (25 persons, 19.4%), x : incurable cases (19 persons, 14.7%). 1) In the last 8 years, there were 30 persons (23.3% of the whole patients) who showed prognostic changes (10 persons improved, 20 persons worsen). While the second group ([symbol: see text]) has seen fewer persons (12 persons down) than previous study, the third group ([symbol: see text]) has seen more persons (9 persons up). Each three groups, that is, the first two groups ([symbol: see text] + [symbol: see text], 44 persons, 34.1%), the third group ([symbol: see text], 41 persons, 31.8%), and the forth and fifth groups ([symbol: see text] + x, 44 persons, 34.1%) accounted for a third of the whole patients. It is after 32 years on the average (extending from 21 to 50 years) from the onset of illness that they showed prognostic changes. 2) Generally speaking, catatonic patients had favorable prognoses, hebephrenic patients unfavorable ones, and paranoid patients medium ones. But 4 improved persons in the forth and fifth groups were all hebephrenic type. 3) 17 among the 30 persons who showed prognostic changes were unstable type. They took a wave-like course. 4) 27 of all the 129 patients were dead. 25 were dead from disease mentioned below. Malignancy (8 persons), Cerebral vascular disease, Pneumonia and Diabetes (3 persons), Heart-failure (2 persons), Ileus, Myocardial infarction, Hepato-cirrhosis, Gastric ulcer, Tuberculosis and Natural death (1 person). 2 persons committed suicide. 5) Outcome of 45 patients who discontinued our medical therapy became clear as follows. [symbol: see text] + [symbol: see text]: 18 persons (40.0%), [symbol: see text]: 9 persons (20.0%), [symbol: see text] + x : 18 persons (40.0%). A smaller percentage of the patients belongs to the third group ([symbol: see text]) than that of our patients who were continuously followed by us. 相似文献
996.
Two-dimensional cross-linked polysiloxane Langmuir-Blodgett (LB) films were prepared and applied to nitric oxide (NO)-permselective membranes in order to block other electroactive interfering species. The cross-linked siloxane LB films deposited on platinum micro-disc electrodes (10 μm in diameter) offered revealing high performances as a permselective membrane for NO sensor such as high sensitivity to NO (detection limit, 40 nM) and high selectivity (e.g., the ratio of current response for acetaminophen or uric acid on the modified electrode to that on the bare electrode, less than 10−3). Furthermore, the permselective membrane could be easily deposited irrespective of the size and shape of electrode. 相似文献
997.
M Nomura K Katada H Anno Y Ogura G Takeshita R Kato H Osawa H Yamamoto T Kanno S Koga 《Canadian Metallurgical Quarterly》1995,55(12):878-884
We examined arteriosclerotic carotid lesions in 76 patients using helical scanning CT (HES-CT), and evaluated the clinical usefulness of this method. A high speed slip-ring X-ray CT system was used. Scanning of the neck was performed for a 30 second period following intravenous bolus injection of non-ionic contrast medium, while couch top movement was 2.0 mm/sec. Multiplannar reconstruction images (MPR-image) and 3-dimensional surface images (3D-image) were reconstructed from the continuous raw data. MPR-images offered axial, coronal and sagittal images in which the lesion could be seen from any direction, and 3D-images that could be freely rotated were obtained by using a track ball and monitor. Eighteen cases were also evaluated by conventional angiography. Excellent HES-CT images were obtained in 73 cases, showing occlusion in 13, stenosis in 34, plaques without calcification in 15 and plaques with calcification in 74 vessels. A good correlation was obtained between HES-CT and angiogram in most cases, and in 6 cases, HES-CT was superior in the detection of stenosis, because it enabled us to observe the lesion from various directions. These results suggested that HES-CT was a minimally invasive, useful diagnostic method for the evaluation of arteriosclerotic carotid disease. 相似文献
998.
Kato K. Hirota O. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2003,49(12):3312-3317
A certain class of mixed states artificially constructed that is used in quantum cryptography is crucial for representation of signals. This correspondence shows that the square-root measurement gives the optimal measurement for such a class of mixed states. 相似文献
999.
1000.
Toshiji Kato 《Electrical Engineering in Japan》2005,152(3):47-54
Circuit simulators have often been used for power electronic system design. However, most of them are limited in their application class to one with fixed elements because they can only handle programmed or fixed element characteristics. To overcome this disadvantage, a simulator should be flexible enough to handle any combination of characteristics of available mathematical functions and operations. It is a problem how to compute Jacobian elements or partial derivatives with respect to circuit variables. This paper proposes a way to compute the derivatives by using the automatic differentiation method which is simple and accurate. The principle and application examples are described. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 152(3): 47–54, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20075 相似文献