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1.
The balanced corpus of contemporary written Japanese (BCCWJ) is Japan’s first 100 million words balanced corpus. It consists of three subcorpora (publication subcorpus, library subcorpus, and special-purpose subcorpus) and covers a wide range of text registers including books in general, magazines, newspapers, governmental white papers, best-selling books, an internet bulletin-board, a blog, school textbooks, minutes of the national diet, publicity newsletters of local governments, laws, and poetry verses. A random sampling technique is utilized whenever possible in order to maximize the representativeness of the corpus. The corpus is annotated in terms of dual POS analysis, document structure, and bibliographical information. The BCCWJ is currently accessible in three different ways including Chunagon a web-based interface to the dual POS analysis data. Lastly, results of some pilot evaluation of the corpus with respect to the textual diversity are reported. The analyses include POS distribution, word-class distribution, entropy of orthography, sentence length, and variation of the adjective predicate. High textual diversity is observed in all these analyses.  相似文献   
2.
For the purpose of investigating a topographical correlation between antigen molecules and protein A-gold(PAG) particles which localized as an immunocytochemical probe, the simplest model on a localization pattern of antigen molecules, which were arranged two-dimensionally on a plane surface of the resin, was used. Ultrathin sections of a G-actin layer, which was adsorbed on epoxy resin and was re-embedded subsequently in JB-4 resin, was stained indirectly with rabbit anti-actin antibody and subsequently by PAG. From this immunoelectron microscopy, a histogram (relative frequency, denoted by y vs. relative length, denoted by x) was obtained using a computer-assisted method. For this histogram, a fitting curve was calculated by a least squares optimization and three parameters (H, U, and W) of the curve which could be useful for a study on the topographical organization of antigen molecules were estimated. Parameter H (maximum y of the curve) would reflect the maximum amount of epitopes at x = U. Half width W, which is the width of the curve at y = H/2, would reflect a breath of epitope masses. This fitting curve was separated into two overlapping curves whose Ws were different from each other. The one constituent curve of which value W was smaller than the other was regarded as a unit curve and the other constituent curve could be resolved into many unit curves whose W values are the same. From these unit curves, the resolution power of the immunoelectron microscopy, using a post-embedding procedure of ultrathin sections, was estimated as 58–66 A°.  相似文献   
3.
Conventional and inverted organic solar cells of poly[9,9‐dioctyl‐fluorene‐co‐bithiophene] (F8T2) as liquid‐crystal semiconducting polymer and fullerene as electron acceptor were fabricated and characterized. An effect of thermal treatment of the films on annealing condition near glass transition was investigated for tuning optimization and improving the photovoltaic and optical properties. Annealing treatment below the glass transition improved the photovoltaic performance and carrier diffusion in crystal growth of active layer. The X‐ray diffraction patterns indicate a crystalline structure with molecular order of F8T2 in crystal index, 100 as a layer distance between sheets of F8T2 chains. The photovoltaic properties were based on molecular interactions with molecular ordering in active layer at crystal state. As the photovoltaic mechanisms, the F8T2 thin film as p‐type semiconducting polymer worked for electron‐donor layer to support light‐induced generation, carrier diffusion and charge transfer near interface in active layer. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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5.
TiNi alloy samples implanted with various fluences of 3 MeV Cu2+ ions were characterized by transmission electron microscope (TEM) and X-ray diffractometer. Cross-sectional TEM images of the samples showed that amorphous region was seen at the fluence of 1014 ions cm?2 in case of ion implantation at 300 K of the substrate temperature, but in case of ion implantation at 100 K it did not appear even at 1015 ions cm?2. These results were also confirmed by X-ray diffraction profiles of the same samples. Consequently, the extent of microstructure change of TiNi alloy by ion implantation was different depending on the substrate temperature.  相似文献   
6.
On the basis of the reliable statistics of rainfall rate and rainfall attenuation for 8 localities in Europe, the spatial correlation coefficient of point rainfall intensity was inferred for each locality from the cumulative distributions of attenuation and rainfall intensity by inversely applying the modified Morita and Higuti rainfall attenuation prediction method. It was found that for European regions the spatial correlation coefficient with an exponential dependence on the horizontal distance is more appropriate for the prediction of rainfall attenuation than that proposed by Morita and Higuti for the Japanese climate. It was also found that although the spatial correlation characteristic varies significantly from one locality to another its variance is not so significant within a particular ccir rainfall climatic zone. This suggests that in predicting the rainfall attenuation it is desirable to employ the spatial correlation coefficient appropriate for the locality to be estimated.  相似文献   
7.
This study reports for the first time in vitro and in vivo properties of fluorapatite (FA)-forming calcium phosphate cements (CPCs). The experimental cements contained from (0 to 3.1) mass % of F, corresponding to presence of FA at levels of approximately (0 to 87) mass %. The crystallinity of the apatitic cement product increased greatly with the FA content. When implanted subcutaneously in rats, the in vivo resorption rate decreased significantly with increasing FA content. The cement with the highest FA content was not resorbed in soft tissue, making it the first known biocompatible and bioinert CPC. These bioinert CPCs might be useful for applications where slow or no resorption of the implant is required to achieve the desired clinical outcome.  相似文献   
8.
Magnetic fine particles of metallic Fe coated with graphitic carbon layers were synthesized by annealing Fe2O3 particles with carbon powders at 1673 K in nitrogen atmosphere. For comparison, SiC was added to Fe2O3. X-ray diffraction measurement showed that the lattice constants of Fe changed depending on the Si contents. Mössbauer spectroscopy confirmed that Fe-Si alloys were formed by the Si addition and that the iron carbide disappeared. Electron microscope images revealed that the thickness of carbon coating layers increased from 24 nm to 36 nm as a result of the Si addition. Soaking tests showed that the corrosion resistance of the carbon-coated Fe particles was improved by the addition of Si. The results suggest that Si caused C to leave the Fe cores and move to the surface to form a carbon coating.  相似文献   
9.
Experimental studies have been carried out on triggering characteristics of the SF6 discharge gap switch by use of XeCl excimer laser (wavelength = 308 nm). First, laser irradiation characteristics are studied on a pure SF6 in the pressure range of p = 160 ~ 3,800 torr. Using a lens of f (focal length) = 133 mm, the laser is irradiated into the gas, where the energy absorption is studied. If the laser is injected into the gas with the energy above a certain threshold for the breakdown, the rate of energy absorption is found to be ~ 17 percent of the incident energy at p > 760 torr. Injecting the laser into the SF6-filled gap switch (gap length = 7 mm, p = 760 torr), we have studied the triggering characteristics. Excellent triggering characteristics were obtained; delay time for the discharge ~ 20 ns, and the jitter ~ 260 ps when the gap voltage is operated at 99 percent of the self-breakdown voltage. In addition, the triggering characteristics are studied by changing the focusing point axially. It is found that both the delay time and the jitter decrease when the focusing point tends to approach the high-voltage electrodes.  相似文献   
10.
Aluminum titanate (AT) ceramic materials doped with alkali feldspar ((Na0.6K0.4)AlSi3O8) have been prepared. These ceramics exhibited high sinterability, large resistance to thermal decomposition, and large flexure strength. The existence of liquid-phase feldspar at sintering temperatures promoted the formation of AT ceramics as the sintering agent. It was considered that silicon ions substituting for aluminum ions at the surface of AT crystal grains lowered the surface energy and hindered the diffusion of Ti4+ and Al3+, giving rise to the large resistance to thermal decomposition. As a result, doping with alkali feldspar was found to effectively improve the mechanical and thermal properties of AT ceramics.  相似文献   
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