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Hyotanishi M Isomura Y Yamamoto H Kawasaki H Obora Y 《Chemical communications (Cambridge, England)》2011,47(20):5750-5752
Surfactant-free Pd nanoclusters (Pd NCs) (size: 1-1.5 nm) showed high catalytic activity in the Suzuki-Miyaura cross-coupling and Mizoroki-Heck reactions. The Pd NCs had a high turnover number, up to 6.0 × 10(8), which can be recycled at least five times without loss of catalytic activity. 相似文献
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A wide range (9.4nm) tuning of vertically coupled microring resonator filter was demonstrated utilizing a large TO coefficient of polymer. The power consumption was about 60mW and no degradation of filter response was observed. 相似文献
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To eliminate the temperature dependence of narrow-band filter, a three-dimensional athermal waveguide of which optical path length is independent of temperature was developed at 1.3 μm wavelength. The temperature coefficient of the refractive index of films made of glass materials was measured at this wavelength, and a strip-loaded athermal waveguide was designed using a scalar finite element method. The temperature coefficient of optical path length was successfully decreased to 9.65X10-9[/K] (0.1% of the conventional waveguide). 相似文献
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Izumi M Tsuruta O Kajihara Y Yazawa S Yuasa H Hashimoto H 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(10):3032-3038
5-Thio-L-fucose-containing trisaccharide H-type II was synthesized. The 3',4'-O-isopropylidene-2-azido-2-deoxylactoside derivative, which was prepared from lactose by azidonitration of lactal, was used as a starting material. By regio- and stereoselective 5-thio-L-fucosylation of the 6,6'-dibenzoate 5 with 5-thiofucosyl trichloroacetimidate 6 and subsequent deprotection gave the 5-thio-L-fucose-containing H-type II 1. Conformational analysis of the 5-thio-L-fucose-containing H-type II and the native H-type II was carried out through NOESY experiments. The observed NOE values between N-acetylglucosamine and galactose, and galactose and fucose were same for these two trisaccharides. However, NOE values between fucose and N-acetylglucosamine were significantly different. Binding of the 5-thio-L-fucose-containing H-type II to lectins and antibodies were in some case stronger and in some case weaker than those of the native trisaccharide. 相似文献
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Hideya Sugimoto Masanori Tachikawa Taro Udagawa 《International journal of quantum chemistry》2019,119(10):e25895
The hydrogen transfer reaction in the reaction of HOSO + NO2 with and without H2O have been investigated using multicomponent quantum-mechanics method, which can directly take nuclear quantum effect (NQE) of light nuclei into account. For the case of the reaction without H2O, our calculation reveals that the reaction leading to trans-HONO is preferred. For the reaction with H2O, water-non-mediated and water-mediated (hydrogen-relay) hydrogen transfer mechanism are investigated. The NQE of hydrogen nucleus lowers the relative energy of the stationary point structures and reduces the activation barrier of the reactions. The largest stabilization is found in the transition state structure of the hydrogen-relay type reaction. H/D isotope effects for the reactions are also analyzed. In particular, H/D isotope effect on the activation barrier is analyzed in detail with the aid of the active strain model. 相似文献
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Hideya Kawasaki Tarui Akira Takehiro Watanabe Kazuyoshi Nozaki Tetsu Yonezawa Ryuichi Arakawa 《Analytical and bioanalytical chemistry》2009,395(5):1423-1431
The availability of robust methods for the species-specific detection of meat and bone meal (MBM) in compound feedingstuffs
is an important prerequisite to enforce current and upcoming European legislation on the use of processed animal proteins
in animal nutrition. Among possible methods, those based on DNA turned out to be a reliable tool for this aim, since DNA is
a quite thermostable molecule able to resist severe heat treatments applied in the manufacturing of animal meals. The application
of such methods by control laboratories implies that the method has been validated including an assessment of its robustness.
Successful transferability between laboratories is considered an important robustness criterion of the method. However, corresponding
guidelines regarding the design of such a study relevant to this field are missing. Here, we demonstrate the feasibility of
an alternative concept that was applied to check for the transferability of a qualitative assay for the detection of banned
MBM in feedingstuffs at trace level based on real-time PCR. The concept was based on an experimental nested design applying
analysis of variance (ANOVA) that was conducted independently in two laboratories and which allows for establishing major
factors influencing the result of analysis. Statistical assessment of the results confirmed the importance of the DNA extraction/purification
step utilised, whereas the PCR step turned out to be a minor factor regarding the overall variability of the results. Furthermore,
blind samples comprised of compound feed adulterated with MBM at 0.1 % and blank compound feed were correctly classified as
"positive" or "negative" samples, thus confirming fitness of purpose for the method. This approach can be of interest for
other research groups working in the development of real-time PCR methods and in their use by control laboratories.
Nested design of the study to check for the transferability of the real-time PCR method 相似文献