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排序方式: 共有307条查询结果,搜索用时 15 毫秒
241.
Xiaoping Hu Kiyohiko Toyoda Minoru Yamanoue Ikko Ihara Kaori Nakai 《Food and Bioprocess Technology》2010,3(6):883-891
Japanese black Wagyu beef has its characteristics of fatty well-marbled texture, flavor, and tenderness which are affected
by fatty acid composition. The aim of this study was to develop an analytical method for evaluating the fatty acid profile
of Wagyu beef by Fourier transform infrared (FTIR) spectroscopy. In the current study, attenuated total reflection–FTIR (ATR-FTIR)
spectroscopy and gas chromatography (GC) were applied to the fat tissues, and the solvent-extracted fats which were sampled
from subcutaneous, inter- and intramuscular fat tissues. Results of GC analysis showed that monounsaturated fatty acids (MUFA)
content became larger in the order of intramuscular, intermuscular, and subcutaneous fats, and saturated fatty acids (SFA)
became smaller in the same order. Subcutaneous fat could be discriminated from inter- and intramuscular fats on the basis
of fatty acid composition by principal component analysis. The ATR-FTIR analysis revealed that the shift of the peak positions
of alkene C–H stretching vibration at around 3,006 cm−1 occurred depending on the unsaturation degree of fatty acids in beef fat. Partial least squares (PLS) regression analysis
with leave-one-out cross-validation was applied to the combined regions of 2,800–3,050 and 1,000–1,500 cm−1 for the fat tissues and the extracted fats. The correlation coefficients of the PLS validation models predicting the content
of the MUFA and SFA for solvent-extracted fats were higher than those for fat tissues, and the coefficients (R
2) of determination more than 0.873 were obtained for solvent-extracted fats and 0.522 for fat tissues. 相似文献
242.
The regulation of palmitoyl-CoA chain elongation (PCE) by clofibric acid [2-(4-chlorophenoxy)-2-methylpropionic acid] was
investigated in comparison with stearoyl-CoA desaturase (SCD) in the liver of obese Zucker fa/fa rats. The proportion of oleic
acid in the hepatic lipids of Zucker obese rats is 2.7 times higher than that of lean littermates. The activities of PCE and
SCD in the liver of Zucker obese rats were markedly higher than in lean rats, and the hepatic uptake of 2-deoxyglucose (2-DG)
was also higher in Zucker obese rats compared with lean rats. The increased activities of SCD and PCE in Zucker obese rats
were due to the enhanced expression of mRNA of rELO1. The proportion of oleic acid in the liver was significantly increased
by the administration of clofibric acid to Zucker obese rats, and the hepatic PCE activity and rELO2 mRNA expression, but
not the SCD activity or SCD1 mRNA expression, were increased in response to clofibric acid treatment. By contrast, the activities
of both PCE and SCD and the mRNA expression of SCD1 and rELO2 in the liver were increased by the treatment of Zucker lean
rats with clofibric acid. Multiple regression analysis, which was performed to determine the relationships involving PCE activity,
SCD activity, and the proportion of oleic acid, revealed that the three parameters were significantly correlated and that
the standardized partial regression coefficient of PCE was higher than that of SCD. These results indicate that oleic acid
is synthesized by the concerted action of PCE and SCD and that PCE plays a crucial role in the formation of oleic acid when
Zucker fa/fa rats are given clofibric acid. 相似文献
243.
Shinagawa E Toyama H Matsushita K Tuitemwong P Theeragool G Adachi O 《Journal of Bioscience and Bioengineering》2008,105(3):292-295
Formaldehyde elimination was successfully carried out with Acetobacter sp. SKU 14, having strong formaldehyde-oxidizing activity in the cytoplasmic membrane. Formaldehyde was decomposed via formate to carbon dioxide by formaldehyde- and formate-oxidizing activities. A resting-cell suspension of the organism was more convenient for practical purposes than the isolated membrane fraction. In Gluconobacter suboxydans IFO 12528, formaldehyde elimination was not so prominent when compared with that in Acetobacter sp. SKU 14. 相似文献
244.
Jun Toyama Koji Ishiguro Takahiro Noda Toru Kumagai Osamu Yamakawa 《Starch - St?rke》2003,55(12):558-563
Eight varieties of sweetpotato [Ipomoea batatas (L.) Lam] were transplanted in June, and harvested in October, November, December 1999 and January 2000. Starch content and starch properties of the tuberous roots were compared on delaying the harvest date. The shoot tops got blighted in early December and chilling injury rate of roots (average of eight varieties) increased up to 76.7% in January with decrease in temperature. Starch contents in October (24.0 g/100 g fresh weight, fw) and November (25.0 g/100 g fw) were almost the same, but the content decreased remarkably in December (21.2 g/100 g fw) and January (15.5 g/100 g fw). In December and January, the sucrose content of the roots had higher values. Hardness and leaked water percentage (LWP) of the starch gels remarkably increased from November to December (hardness: 76.4 to 112.3 g, LWP: 6.6 to 10.9%). On the contrary, the changes in amylose content and pasting properties of the starches were not consistent with decrease in temperature. This suggests that the effect of low temperature on these properties is insignificant after the growth period of sweetpotato. There were significant differences among the varieties in terms of starch retrogradation. The selection of varieties such as Kyushu 123 with the lowest percentage of retrogradation and Kyukei90142‐8 with the lowest chilling injury rate will help to lengthen the storage time in the field at least until December. 相似文献
245.
A novel temperature-stable light-emitting diode 总被引:2,自引:0,他引:2
A new type of light-emitting diode (LED) has been developed, the light intensity of which is stable during temperature change. This device consists of a multilayer dielectric optical filter on the surface of a conventional LED. The transmissivity of the optical filter is low for the short wavelength region of the LED's light spectrum and high for the long wavelength region. When the LED's temperature increases, the spectrum of LED light shifts toward the long wavelength side because of the shrinkage of the energy gap of the compound semiconductor. The shift increases the total transmission of the light because the transmissivity is high for the long wavelength region. This increase compensates for the decrease of the LED light intensity, which is caused by the decrease of the internal quantum efficiency. The effect of this filter is confirmed by both calculation and experiment 相似文献
246.
Frequency pulling in a Brillouin fiber ring laser 总被引:1,自引:0,他引:1
The lasing frequencies of a Brillouin fiber ring laser are shifted slightly from the resonant frequencies of the cold fiber ring resonator due to the optical Kerr effect and the nonlinear phase shift associated with stimulated Brillouin scattering (SBS) used as the gain mechanism in this type of laser. These frequency pulling effects are investigated in detail both theoretically and experimentally. The results of this study are useful in many Brillouin fiber ring laser applications such as Brillouin fiber optic gyroscopes, microwave generators, and frequency shifters. To the authors' knowledge this is the first time the frequency pulling effect caused by the nonlinear phase shift associated with SBS is reported 相似文献
247.
248.
Preparation of highly functionalized thermoresponsive composites containing TiO2/Fe3O4 nanoparticles
Junichi Ida Fumiko Matsushima Masanori Ochi Kiyohiko Funasho Soshi Watanabe Tatsushi Matsuyama Hideo Yamamoto 《Polymer Composites》2016,37(8):2293-2300
Highly functionalized thermoresponsive composites in which two kinds of functional inorganic particles and thermoresponsive polymer work concertedly were prepared. In this study, poly(N‐isopropylacrylamide) and calcium alginate were used as the thermoresponsive polymer and structure support polymer, respectively. TiO2 and Fe3O4 were used as functional inorganic nanoparticles. The thermoresponsive functional composites were prepared using a single‐tube nozzle by modifying the simple process to prepare microcapsules reported in our previous study. The experimental results showed that the TiO2/Fe3O4‐embedded thermoresponsive composites were successfully obtained. The resulting composites exhibited thermoresponsive volume change and photocatalytic activity. Localized heating of the thermoresponsive bead containing Fe3O4 was also achieved by applying an alternating current (AC) magnetic field on the bead. Because of the localized heating property, repeated shrinking‐swelling movement (i.e., pumping movement) of the composite was achieved by applying an AC magnetic field intermittently. Finally, based on the experimental results, the effect of the promoted mass transfer of the substrate and product due to thermoresponsive pumping on the enhancement of the apparent photocatalytic activity was simulated. The results showed the effectiveness of thermoresponsive pumping in improving the apparent photocatalytic activity of TiO2 nanoparticles embedded in the composite gel. POLYM. COMPOS., 37:2293–2300, 2016. © 2015 Society of Plastics Engineers 相似文献
249.
Keiji Komatsu Tetsuo Sekiya Ayumu Toyama Yasuhiro Hasebe Atsushi Nakamura Masahiro Noguchi Yu Li Shigeo Ohshio Hiroki Akasaka Hiroyuki Muramatsu Hidetoshi Saitoh 《Journal of Thermal Spray Technology》2014,23(5):833-838
R2O3 (R = Y, Eu, Er) metal oxides were synthesized from metal–ethylenediaminetetraacetic acid (EDTA) complexes using a flame spray technique. As this technique enables high deposition rates, films with thickness of several tens of micrometers were obtained. Films of yttria, europia, and erbia phase were synthesized on stainless-steel substrates with reaction assistance by H2–O2 combustion gas. The oxide films consisted of the desired crystalline phase with micropores. The porosity of the films was in the range of 6–15%, varying with the metal used. These results suggest that the true density of the metal oxide obtained from metal–EDTA powder through the thermal reaction process plays an important role in achieving film with the desired porosity. 相似文献
250.
Toshiisa Konishi Yukiko Horiguchi Minori Mizumoto Michiyo Honda Kazuya Oribe Hikaru Morisue Ken Ishii Yoshiaki Toyama Morio Matsumoto Mamoru Aizawa 《Journal of materials science. Materials in medicine》2013,24(3):611-621
The hydroxyapatite (HAp) powder preparation process was optimized to fabricate inositol phosphate-HAp (IP6-HAp) cement with enhanced mechanical properties. Starting HAp powders were synthesized via a wet chemical process. The effect of the powder preparation process on the morphology, crystallinity, median particle size, and specific surface area (SSA) of the cement powders was examined, together with the mechanical properties of the resulting cement specimens. The smallest crystallite and median particle sizes, and the highest SSA were obtained from ball-milling of as-synthesized HAp powder under wet conditions and then freeze-drying. IP6-HAp cement fabricated with this powder had a maximum compressive strength of 23.1 ± 2.1 MPa. In vivo histological studies using rabbit models revealed that the IP6-HAp cements were directly in contact with newly formed and host bones. Thus, the present chelate-setting HAp cement is promising for application as a novel paste-like artificial bone. 相似文献