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261.
Aiko Nakano Atsuhiro Osuka Iwao Yamazaki Tomoko Yamazaki Yoshinobu Nishimura 《Angewandte Chemie (International ed. in English)》1998,37(21):3023-3027
Up to 14 porphyrin rings are present in the title compounds 1 , which are readily available with high regioselectivity from linear nickel–zinc porphyrins. Upon irradiation with light a rapid energy transfer from the peripheral porphyrin rings to the diporphyrin core takes place. 相似文献
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Toru Shigematsu Nobuya Okada Kazuki Nomura Chihiro Kataoka Saori Hori Iwao Takahashi 《高压研究》2019,39(2):313-323
ABSTRACTUnpasteurized draft sake has a potentially high market value, due to its fresh flavor and fruity taste, compared with conventional thermal-pasteurized sake. However, the shelf life of draft sake is limited. To increase the shelf life of draft sake, it is necessary to suppress flavor and taste deterioration resulting from inactivation of enzymes produced by koji-mold. Draft sake was treated with high hydrostatic pressure (HHP) of 200 to 500?MPa at ?7 to 50°C to analyze the inactivation of α-amylases, glucose-forming enzymes, and acid carboxypeptidases. We found significant inactivation of enzymes produced by koji-mold in draft sake subjected to HHP treatment at both high and low temperature. However, HHP treatment at low temperature effectively inactivated enzymes while retaining the fresh flavor and fruity taste of draft sake. 相似文献
265.
Yukiko Uekaji Daisuke Nakata Hirokazu Shiga Ayako Jo Iwao Tachi Hiroshi Fukumi Akihito Urano Keiji Terao 《Journal of inclusion phenomena and macrocyclic chemistry》2011,70(3-4):447-451
We have already reported the enhancement of the stability and bioavailability of coenzyme Q10 (CoQ10) oxidized form by γ-cyclodextrin (γCD) complexation. In a series of the studies, we investigated an easy and economical conversion of CoQ10 oxidized form to its reduced form in complex powder, using inexpensive vitamin C (VC) as the reductant. CoQ10 oxidized form or its γCD complex and VC were physically mixed at the molar ratio of 1:0 to 1:50. The mixtures were stored at 60 °C and 75% RH. The sampling was made at certain interval, and both CoQ10 oxidized and reduced form contents were measured by high performance liquid chromatography (HPLC). The result shows that the conversion ratio to CoQ10 reduced form in γCD complex was significantly higher than that of non-inclusion compound (ca. 80% versus ca. 30% at the maximum). It was also confirmed that CoQ10 reduced form in γCD complex remains as stable as its oxidized form in γCD complex. Free radical scavenging potential of partially reduced CoQ10–γCD complex was assayed with 1,1-diphenyl-2-picrylhydrazyl (DPPH). 相似文献
266.
Hideo Sagawa Jana Mendrok Takamasa Seta Hiromichi Hoshina Philippe Baron Kodai Suzuki Iwao Hosako Chiko Otani Paul Hartogh Yasuko Kasai 《Journal of Quantitative Spectroscopy & Radiative Transfer》2009,110(18):2027-2036
Carbon dioxide (CO2) induced pressure broadening coefficients of water vapor (H2O) lines have been determined using a terahertz time-domain spectrometer (TDS). Thirty-two rotational transitions of H2O were observed in the spectral range of 18– (550–3050 GHz) for the first time. Using TDS allows one to measure absorption spectra with one order of magnitude better precision than Fourier transform spectrometer in this frequency region. The precision of our broadening coefficient measurements was 2.4% in average. The measured CO2 induced pressure broadening coefficients are compared to those calculated by the complex Robert–Bonamy formalism. The difference between the measurement and the theoretical estimation was in the range of -10.7% to +19.0% confirming the credibility of the theoretical approach. The impact on retrieval of water vapor abundance was examined by performing inversion analysis on H2O spectra of Venus atmosphere obtained with the Submillimeter Wave Astronomy Satellite. In this example case, the retrieved water vapor mixing ratio reduces by half at the altitude region of 70–85 km when applying the newly measured broadening coefficient compared to the air-broadening coefficient, and changes by 5% compared to that estimated by the complex Robert–Bonamy formalism. 相似文献
267.
Yang JH Song KS Zhang GJ Degawa M Sasaki Y Ohdomari I Kawarada H 《Langmuir : the ACS journal of surfaces and colloids》2006,22(26):11245-11250
Here, we report a novel method of micropatterning oligonucleotides via aromatic groups as linkers on partially amino-terminated diamond and the inherence on subsequent hybridization. The covalent immobilization of probe oligonucleotides and characterization of immobilized probe oligonucleotides with carboxylic compounds were investigated by X-ray photoelectron spectroscopy (XPS). To confirm the effects of linker flexibility in a low amino group on diamond for probe oligonucleotides, three kinds of dicarboxylic compound--adipic acid, terephthalic acid, and trimesic acid--were used for immobilization of probe oligonucleotides, like linkers; and these oligonucleotides were hybridized with target oligonucleotides labeled with Cy 5 on the micropatterned diamond surface. The hybridization intensities determined by epifluorescence microscopy were compared and analyzed. 相似文献
268.
Shuji Noguchi Haruka Atsumi Yasunori Iwao Toshiyuki Kan Shigeru Itai 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(2):124-127
Nobiletin [systematic name: 2‐(3,4‐dimethoxyphenyl)‐5,6,7,8‐tetramethoxy‐4H‐chromen‐4‐one; C21H22O8] is a flavonoid found in citrus peels, and has been reported to show a wide range of physiological properties, including anti‐inflammatory, anticancer and antidementia activities. We have solved the crystal structure of nobiletin, which revealed that the chromene and arene rings of its flavone moiety, as well as the two methoxy groups bound to its arene ring, were coplanar. In contrast, the C atoms of the four methoxy groups bound to the chromene ring are out of the plane, making the molecule conformationally chiral. A comparison of the crystal structures of nobiletin revealed that it could adopt a variety of different conformations through rotation of the covalent bond between the chromene and arene rings, and the orientations of methoxy groups bound to the chromene ring. 相似文献
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270.
Iwao Omae 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4-5):891-897
Organometallic intramolecular-coordination five-membered ring compounds show high reactivity and high selectivity. Therefore, these many compounds have been synthesized since around mid 1960s. More than 50 kinds of metals are found as the metal elements, and these compounds are very widely used as intermediates and catalysts for organic syntheses. 相似文献