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排序方式: 共有389条查询结果,搜索用时 17 毫秒
61.
Masao Shimizu Naoto Kudo Yoshinobu Nakajima Noboru Matsuo Yoshihisa Katsuragi Ichiro Tokimitsu Francisca Barceló 《Journal of the American Oil Chemists' Society》2008,85(7):629-633
Olive oils have a higher relative diacylglycerol (DAG) content than other plant oils. The lipase in olive fruits is involved
in DAG production and is directly related to the acidity of the olive oil. However, the lipase activity and positional selectivity
have not been clarified. To investigate the properties of olive fruit lipase, olive fruits of the Mission variety harvested
during mid-December of 2005 on Shodoshima Island (Japan) were stored at 20, 30 or 40 °C for 4 weeks. Changes in the acidity
and acylglycerol content of the oils extracted from the stored fruits were analyzed. The acidity and DAG content of the olive
oils increased due to triacylglycerol (TAG) hydrolysis during storage. sn-1,2-DAGs preferentially increased during the early stages of storage, indicating that the olive fruit lipase is enantioselective
for the sn-3 position, while non-enzymatic isomerization of sn-1,2-DAGs was observed throughout the entire duration of storage. Kinetic analysis revealed that the enantioselectivity of
olive fruit lipase for the sn-3 position was approximately four times greater than for the sn-1 position. The lipase was gradually inactivated at temperatures of 30 °C or higher, and the ratios of the rate constant
for inactivation to TAG hydrolysis at the sn-3 position was 0.2, 13, and 23 at 20, 30, and 40 °C, respectively. 相似文献
62.
The tensile properties and fracture behavior of ultrahigh tensile strength PAN-based (T1000GB), ultrahigh modulus pitch-based (K13D) and high ductility pitch-based (XN-05) carbon fibers have been investigated. The statistical distributions of the tensile strength were characterized. The Weibull modulus for the T1000GB, K13D and XN-05 fibers were calculated to be 5.9, 4.2 and 7.9, respectively. The results clearly show that for PAN- and pitch-based carbon fibers, the Weibull modulus decreases with an increase in the tensile modulus and the mean tensile strength. 相似文献
63.
Joao Gari da Silva Fonseca Takashi Oozeki Takumi Takashima Gentarou Koshimizu Yoshihisa Uchida Kazuhiko Ogimoto 《Progress in Photovoltaics: Research and Applications》2012,20(7):874-882
The development of a methodology to forecast accurately the power produced by photovoltaic systems can be an important tool for the dissemination and integration of such systems on the public electricity grids. Thus, the objective of this study was to forecast the power production of a 1‐MW photovoltaic power plant in Kitakyushu, Japan, using a new methodology based on support vector machines and on the use of several numerically predicted weather variables, including cloudiness. Hourly forecasts of the power produced for 1 year were carried out. Moreover, the effect of the use of numerically predicted cloudiness on the quality of the forecasts was also investigated. The forecasts of power production obtained with the proposed methodology had a root mean square error of 0.0948 MW h and a mean absolute error of 0.058 MW h. It was also found that the forecast and measured values of power production had a good level of correlation varying from 0.8 to 0.88 according to the season of the year. Finally, the use of numerically predicted cloudiness had an important role in the accuracy of the forecasts, and when cloudiness was not used, the root mean square error of the forecasts increased more than 32%, and the mean absolute error increased more than 42%. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
64.
Deposited road particles (DRPs) collected from 13 heavily traveled roadways in an urban area of Southern Lake Biwa, Japan, were analyzed for polycyclic aromatic hydrocarbons (PAHs) in seven different particle size fractions (< or = 20 to 1000-2000 microm) and evaluated for the aryl hydrocarbon receptor (AhR) ligand activity by using a yeast bioassay. The mean compositions of individual PAHs to total PAH concentrations in different particle size fractions were 19-21% for pyrene, which was the most dominant component, 14-16% for fluoranthene, and 7-13% for benzo[g,h,i]perylene, which were the next dominant components. The total PAH distribution pattern in different particle size fractions of DRPs was different from the organic matter distribution pattern which increased with decreasing particle size of DRPs, and could be explained by the differences in their sources. Moreover, AhR ligand activities were observed in the DRP extracts of all size fractions. The activity of the DRP extracts from the smallest size fraction was approximately 5 times more potent than that of the largest size fraction in a yeast AhR ligand activity assay. The mean contribution (%) of benzo[k]-fluoranthene, chrysene, benzo[b]fluoranthene, and benzo[a]pyrene to the AhR activity of DRP extracts in all size fractions was 1.43-4.11%, 1.63-3.53%, 0.63-1.69%, and 0.31-1.42%, respectively. Although the contribution of PAHs to AhR ligand activity presented in the DRP extracts was relatively low (below 10%), it may be best to remove these DRPs before discharge to receiving water environments. 相似文献
65.
66.
Characterization of electrical properties and photosensitivity of SnS thin films prepared by the electrochemical deposition method 总被引:2,自引:0,他引:2
Naoya Sato Masaya Ichimura Eisuke Arai Yoshihisa Yamazaki 《Solar Energy Materials & Solar Cells》2005,85(2):153-165
Using the electrochemical deposition (ECD) method, we prepared tin sulfide thin films, which are suitable for the absorption layer in solar cells because of its bandgap energy (1 eV). We first optimized pulse-form biasing for ECD by characterizing deposited samples with scanning electron microscope, Auger electron spectroscopy and X-ray diffraction measurements. Then, we investigated the electrical properties of deposited SnS thin films and the properties of contacts with several different metals. Furthermore, we observed the photoconductivity of the films by means of photoelectrochemical measurements. From these results, we confirmed that the SnS thin films show p-type conduction. 相似文献
67.
Tsunenori Watanabe Yoshihisa MikiTakeo Masuda Hiroshi DeguchiHiroyoshi Kanai Saburo HosokawaKenji Wada Masashi Inoue 《Ceramics International》2011,37(8):3183-3192
Synthesis of the γ-Ga2O3-Al2O3 solid solutions by spray pyrolysis was examined. Spherical particles were obtained using an aqueous solution of Al(NO3)3 and Ga(NO3)3 with HNO3. For Ga-rich composition, γ-phase solid solutions were directly crystallized by the spray pyrolysis. For Al-rich composition, spray pyrolysis gave amorphous products unless a sufficient thermal energy was supplied during the spray pyrolysis. Subsequent calcination of the amorphous products gave γ-Ga2O3-Al2O3 solid solutions. However, physical properties of the solid solutions were affected by the spray pyrolysis conditions. 相似文献
68.
Wataru Umishio Toshiharu Ikaga Yoshihisa Fujino Shintaro Ando Tatsuhiko Kubo Yukie Nakajima Tanji Hoshi Masaru Suzuki Kazuomi Kario Takesumi Yoshimura Hiroshi Yoshino Shuzo Murakami 《Indoor air》2020,30(6):1317-1328
The WHO Housing and health guidelines recommend a minimum indoor temperature of 18°C to prevent cold-related diseases. In Japan, indoor temperatures appear lower than in Euro-American countries because of low insulation standards and use of partial intermittent heating. This study investigated the actual status of indoor temperatures in Japan and the common characteristics of residents who live in cold homes. We conducted a nationwide real-world survey on indoor temperature for 2 weeks in winter. Cross-sectional analyses involving 2190 houses showed that average living room, changing room, and bedroom temperatures were 16.8°C, 13.0°C, and 12.8°C, respectively. Comparison of average living room temperature between prefectures revealed a maximum difference of 6.7°C (Hokkaido: 19.8°C, Kagawa: 13.1°C). Compared to the high-income group, the odds ratio for living room temperature falling below 18°C was 1.38 (95% CI: 1.04-1.84) and 2.07 (95% CI: 1.28-3.33) for the middle- and low-income groups. The odds ratio was 1.96 (95% CI: 1.19-3.22) for single-person households, compared to households living with housemates. Furthermore, lower room temperature was correlated with local heating device use and a larger amount of clothes. These results will be useful in the development of prevention strategies for residents who live in cold homes. 相似文献
69.
70.
Large Magnetovolume Effect Induced by Embedding Ferromagnetic Clusters into Antiferromagnetic Matrix of Cobaltite Perovskite 下载免费PDF全文
Ping Miao Xiaohuan Lin Akihiro Koda Sanghyun Lee Yoshihisa Ishikawa Shuki Torii Masao Yonemura Takashi Mochiku Hajime Sagayama Shinichi Itoh Kazutaka Ikeda Toshiya Otomo Yinxia Wang Ryosuke Kadono Takashi Kamiyama 《Advanced materials (Deerfield Beach, Fla.)》2017,29(27)
Materials that show negative thermal expansion (NTE) have significant industrial merit because they can be used to fabricate composites whose dimensions remain invariant upon heating. In some materials, NTE is concomitant with the spontaneous magnetization due to the magnetovolume effect (MVE). Here the authors report a new class of MVE material; namely, a layered perovskite PrBaCo2O5.5+x (0 ≤ x ≤ 0.41), in which strong NTE [β ≈ ?3.6 × 10?5 K?1 (90–110 K) at x = 0.24] is triggered by embedding ferromagnetic (F) clusters into the antiferromagnetic (AF) matrix. The strongest MVE is found near the boundary between F and AF phases in the phase diagram, indicating the essential role of competition between the F‐clusters and the AF‐matrix. Furthermore, the MVE is not limited to the PrBaCo2O5.5+x but is also observed in the NdBaCo2O5.5+x . The present study provides a new approach to obtaining MVE and offers a path to the design of NTE materials. 相似文献