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排序方式: 共有776条查询结果,搜索用时 31 毫秒
91.
Corlu A Choe R Durduran T Lee K Schweiger M Arridge SR Hillman EM Yodh AG 《Applied optics》2005,44(11):2082-2093
We present an algorithm that explicitly utilizes the wavelength dependence of tissue optical properties for diffuse optical tomography. We have previously shown that the method gives superior separation of absorption and scattering. Here the technique is described and tested in detail, and optimum wavelength sets for a broad range of chromophore combinations are discovered and analyzed. 相似文献
92.
Seoung-Hwan Park Weon-Guk Jeong Byung-Doo Choe 《Photonics Technology Letters, IEEE》1994,6(11):1297-1299
The effect of high temperature on the threshold current density and the gain of InxGa1-xAs/InGaAsP (Eg=1.6 eV) QW lasers lattice matched to GaAs is investigated theoretically. These results are also compared with those of Inx Ga1-xAs/GaAs QW lasers. It is found that better performance can be achieved in InGaAs/InGaAsP lasers compared to InGaAs/GaAs lasers at high temperature. This is due to the fact that the temperature dependence of the threshold carrier density for InGaAs/InGaAsP lasers is weaker than that for InGaAs/GaAs lasers. The calculated characteristic temperature is in good agreement with reported experimental results 相似文献
93.
Han S. Uhm Joon Y. Choe Chung M. Kim 《Journal of Infrared, Millimeter and Terahertz Waves》1983,4(3):361-374
Stability properties of the free streaming mode in an electron beam propagating through a cylindrical waveguide loaded with a tape helix are investigated, including influence of high space harmonic perturbations. Closed algebraic dispersion relation of the free streaming mode are obtained. Properties of the high space harmonic perturbations are numerically investigated in connection with application on a high frequency microwave amplifier. One of the most important features in this analysis is that instability of high harmonic perturbations occurs at a very large value of microwave frequency. In this regard, millimeter microwave can be easily attainable by reducing the helix radius to a subcentimeter. 相似文献
94.
Jun Ho Kim Wan Sik Jung Gui Seck Bae Ho Jin Heo Dae-Ok Kim Jin A. Yoon Sangho Kim Young Jun Kim 《Food science and biotechnology》2010,19(1):267-270
This study was designed to evaluate the effect of the oral administration of fruit extracts (lemon and Japanese apricot) combined
with red-ginseng on the endurance and availability of metabolic substrates in ICR mice. Administration of the fruit extracts
and red-ginseng (RG) (1:1) significantly increased swimming capacity, by 40%, with increased expenditures of non-esterified
fatty acids and triglycerides in the plasma of the mice after 1 week of feeding. There was no significant increase in swimming
capacity with the fruit extract alone. These results suggest that the fruit extract could synergistically elevate the effects
of red-ginseng on swimming capacity in the mice by increasing fat utilization and reducing the consumption of stored glucose. 相似文献
95.
Hak-Su Kang Kyeong-Nam Park Young-Rae Cho Dae-Won Park Youngson Choe 《Journal of Industrial and Engineering Chemistry》2009,15(5):752-757
C60-doped 2-TNATA (4,4′,4″-tris(2-naphthylphenylamino)triphenylamine) as a hole injection material and NPD (4,4′bis[N-(1-naphthyl)-N-phenyl-amino]biphenyl) as a hole transport material are used to fabricate OLEDs via vacuum deposition process in this study. C60-doped 2-TNATA film was treated by means of thermal annealing and in situ electromagnetic field. According to AFM, SEM, XRD, and Raman spectra results, by both thermal annealing and in situ electromagnetic field treatments, the smoothened surface and the closely packed morphology of 2-TNATA:C60 film was obtained without any evidences of crystalline nature after those treatments. The treatments eventually lead to enhancing the current density and efficiency of the multi-layered ITO/2-TNATA:C60 (5% doped) (70 nm)/NPD (30 nm)/Alq3 (50 nm)/LiF (1 nm)/Al (100 nm) devices by facilitating hole injection/transport in the multi-layered organic devices. Consequently, thermal annealing treatment for the 2-TNATA:C60 film is preferred rather than in situ electromagnetic field treatment so as to improve the overall performance of the organic light-emitting diodes in this study. 相似文献
96.
Yu Hyung-Seok Lee Na-Kyoung Choi Ae-Jin Choe Jeong-Sook Bae Chun Ho Paik Hyun-Dong 《Food science and biotechnology》2019,28(3):851-855
Food Science and Biotechnology - The objective of this study was to evaluate the functional properties of Weissella cibaria JW15 (JW15) by investigating its antagonistic and antioxidant activities.... 相似文献
97.
This study compared stabilities of tocopherols and lutein in oil extracted from roasted mustard seeds (RMSO) with those in
oil from unroasted seeds (URMSO) during oil oxidation at 60°C in the dark for 12 days. Tocopherols and lutein were determined
by high performance liquid chromatography, and the oil oxidation was monitored with conjugated dienoic acid (CDA) content
and fatty acid composition by gas chromatography. The rate of CDA increase was lower in RMSO (0.038%/day) than in URMSO (0.047%/day)
during 12-day oxidation in the dark, with little change in fatty acid composition in both oils. Tocopherols and lutein were
more abundant in RMSO, initially 465.38 and 100.55 μg/g, respectively, than in URMSO, and their stability was higher in RMSO
(−4.63 and −5.94%/day of degradation in tocopherols and lutein, respectively) than in URMSO during 12-day oxidation of oil,
both of which contributed to higher autoxidative stability of RMSO than URMSO. 相似文献
98.
99.
100.
Sangho Koh Seika Imamura Naoto Fujino Masahiro Mizuno Nobuaki Sato Satoshi Makishima Peter Biely Yoshihiko Amano 《Journal of Applied Glycoscience》2019,66(4):131
The carbohydrate esterase family 1 (CE1) in CAZy contains acetylxylan esterases (AXEs) and feruloyl esterases (FAEs). Here we cloned a gene coding for an AXE belonging to CE1 from Irpex lacteus (IlAXE1). IlAXE1 was heterologously expressed in Pichia pastoris, and the recombinant enzyme was purified and characterized. IlAXE1 hydrolyzed p-nitrophenyl acetate, α-naphthyl acetate and 4-methylumbelliferyl acetate, however, it did not show any activity on ethyl ferulate and methyl p-coumarate. We also examined the activity on partially acetylated and feruloylated xylan extracted from corncob by hydrothermal reaction. Similarly, ferulic and p-coumaric acids were not liberated, and acetic acid was only detected in the reaction mixture. The results indicated that IlAXE1 is an acetylxylan esterase actually reacted to acetyl xylan. However, since IlAXE1 was unable to completely release acetic acid esterifying xylopyranosyl residues, it is assumed that acetyl groups exhibiting resistance to deacetylation by IlAXE1 are present in corn cob xylan. 相似文献