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Characterization by Auger electron spectroscopy (AES) and Fourier transformation infrared spectroscopy (FTIR) confirms (Ta2O5)x(Al2O3)1−x alloys are homogeneous pseudo-binary alloys with increased thermal stability with respect to end member oxides, Ta2O5 and Al2O3. Capacitance–voltage (C–V) and current density–voltage (J–V) data as a function of temperate show that the Ta d-states of the alloys act as localized electron traps, and are at an energy approximately equal to the conduction band offset of Ta2O5 with respect to Si. 相似文献
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We demonstrate a bidirectional WDM self-healing ring network for hub/remote nodes with one fiber. In this network, self-healing can be achieved within 8 ms. The transmission capacity can be doubled in the operating state. 相似文献
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Kang HM Ryong Kim J Jeong TS Choi SG Ryu YH Taeg Oh G Baek NI Kwon BM 《Natural product research》2006,20(2):139-143
Two cyclic diarylheptanoids, garugamblin-3 (1) and acerogenin L (2), isolated from the MeOH extract of the fruits of Alnus japonica Steud., inhibited human low-density lipoprotein (LDL) oxidation in the thiobarbituric acid-reactive substance assay with IC50 values of 2.9 and 1.7 microM, respectively, and they also inhibited cell-mediated LDL oxidation more than five times more strongly than that of a well-known antioxidant, probucol, at a concentration of 10 microM. 1 had no effect on the anti-atherogenesis in low-density lipoprotein receptor- deficient mice. 相似文献
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[reaction: see text] Sequential application of the Kulinkovich cyclopropanation of carboxylic esters and RCM of the resulting cis-dialkenyl-tethered cyclopropanols provides an expedient route to functionalized medium-sized carbocycles. Subsequent elaboration of the cyclopropanol functionality, such as one-carbon ring expansion, to afford synthetically useful alpha,beta-enones is also worth noting. 相似文献
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Seung-Man Yu Seung-Hong Choi Sae-Sark Kim Eun-Hoe Goo Youn-Sang Ji Bo-Young Choe 《Current Applied Physics》2013,13(5):857-863
The optimal volume of contrast medium must be injected into the patient who emits the maximum signal intensity in an ROI. This study was investigated four different type MRI and one CT contrast agent in vitro and sought to establish relations between concentration, MRI relaxivity, CT Hounsfield unites selected kVp and different MRI T1 sequences. Using a CT contrast medium and four different MRI T1 contrast media, we developed five different phantom series. The MRI contrast media phantom was imaged on 1.5T and 3T MRI systems and measured the R1 and R2 value. A CT scanner was used to obtain images of the Iopromide 370 phantom with the quality of radiation to obtain images. The Pearson's correlation coefficient analyses were conducted between MRI CM phantom series with Iopromide 370 phantom. The non-parametric statistical analyses were performed for the values of kVp. The ΔHU of the test solution of the CT contrast media was produced in the same amount as the exponentially increased concentration of the MRI contrast media according to the increase in the dilution concentration, and was influenced by the quality of the X-ray. Through the results of this experiment that considered the two aforementioned factors, an image with a high diagnosis value can be acquired from the information on the concentration of the MRI T1 contrast media. 相似文献
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Jacqueline Pollini Dr. Wolf M. Pankau Prof. Lukas J. Gooßen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(31):7416-7425
Isomerizing olefin metathesis is currently undergoing a transformation from laboratory curiosity to powerful synthetic concept at the heart of orthogonal tandem catalysis. In this process, an isomerization catalyst continuously moves double bonds along carbon chains, while a metathesis catalyst scrambles the residues at the C−C double bonds. This cooperative action of two catalysts can be used to access single, defined products from a complex mixture of compounds. Alternatively, it enables the transformation of uniform starting materials into complex product blends with defined, tunable properties. This concept article highlights recent developments and potential applications of this fascinating reaction concept. 相似文献
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