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91.
92.
Sun-Chan Jeong Ichiro Katayama Hirokane Kawakami Yutaka Watanabe Hironobu Ishiyama Nobuaki Imai Yoshikazu Hirayama Hiroari Miyatake Masao Sataka Hiroyuki Sugai Satoru Okayasu Shin-Ichi Ichikawa Katsuhisa Nishio Shinichi Mitsuoka Takamitsu Nakanoya Takashi Hashimoto Takanori Hashimoto Masahito Yahagi 《Solid State Ionics》2009,180(6-8):626-630
The diffusion coefficients of Li in the NaTl-type Li intermetallic compound of β-LiGa have been measured by using a short-lived radioactive diffusion tracer. As the tracer, the α-emitting radioisotope of 8Li delivered as the energetic and pulsed beam from Tokai Radioactive Ion Accelerator Complex (TRIAC) was implanted into the β-LiGa compounds with the composition in the range of about 43 to 54 at.% Li. By analyzing the time-dependent yields of the α-particles measured according to the repetition cycle of the beam, the tracer diffusion coefficients were extracted over the wide range of Li composition. Abnormal composition-dependence of Li diffusion coefficients in β-LiGa was observed; the stoichiometric β-LiGa showed the highest diffusivity of Li. By referring to the composition-dependent diffusivity of Li in the iso-structural β-LiAl and β-LiIn, we could identify the abnormal diffusion of Li in very Li-poor composition of β-LiGa. The anomaly has been discussed qualitatively in terms of the formation of defect complex and the interaction between the constitutional defects. 相似文献
93.
We classify normal supersingular K 3 surfaces Y with total Milnor number 20 in characteristic p,where p is an odd prime that does not divide the discriminant of the Dynkin type of the rational double points on Y.This paper appeared in preprint form in the home page of the first author in the year 2005. 相似文献
94.
Dieter Wohrle Jörg Gitzel Gerhard Krawczyk Eishun Tsuchida Hiroyoki Ohno Ichiro Okura 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(10-11):1227-1254
Metal complexes of covalently bound porphyrins are used as sensitive probes for several investigations. Substituted derivatives of tetraphenyl-porphin, phthalocyanine, and naphthalocyanine are synthesized at positively and negatively charged as well as uncharged polymers. The photo-redox activities were studied under irradiation with visible light in the presence of a donor and an acceptor. The triplet life times of covalently bound porphyrin moieties are strongly enhanced compared with the analogous monomeric porphyrins. In addition, the polymer binding results in higher photocatalytic activity. The electron-transfer reactions of Mn(III)-containing porphyrins using the reducing agent dithionite are strongly influenced by the polymer environment. In contrast to monomeric Mn(III)-porphyrins, the porphyrins containing polymers exhibit a two-step reduction which may be due to the change of the conformation of the polymer coil. The catalytic epoxidation of 2,5-dihydrofuran with hypochlorite with formation of 3,4-epoxytetrahydrofuran occurs with water-soluble porphyrins in water. No influence of the polymer environment exists. The different reactions require reaction times from milliseconds up to hours. 相似文献
95.
Dr. Jun‐ichi Matsuo Prof. Dr. Masahiro Murakami 《Angewandte Chemie (International ed. in English)》2013,52(35):9109-9118
A directed cross‐aldol reaction of silyl enol ethers with carbonyl compounds, such as aldehydes and ketones, promoted by a Lewis acid, a reaction which is now widely known as the Mukaiyama aldol reaction. It was first reported in 1973, and this year marks the 40th anniversary. The directed cross‐aldol reactions mediated by boron enolates and tin(II) enolates also emerged from the Mukaiyama laboratory. These directed cross‐aldol reactions have become invaluable tools for the construction of stereochemically complex molecules from two carbonyl compounds. This Minireview provides a succinct historical overview of their discoveries and the early stages of their development. 相似文献
96.
Dr. Neil J. Stewart Hitomi Nakano Shuto Sugai Mitsushi Tomohiro Yuki Kase Yoshiki Uchio Dr. Toru Yamaguchi Yujirou Matsuo Dr. Tatsuya Naganuma Dr. Norihiko Takeda Dr. Ikuya Nishimura Dr. Hiroshi Hirata Dr. Takuya Hashimoto Dr. Shingo Matsumoto 《Chemphyschem》2021,22(10):915-923
Hyperpolarized [1-13C]fumarate is a promising magnetic resonance imaging (MRI) biomarker for cellular necrosis, which plays an important role in various disease and cancerous pathological processes. To demonstrate the feasibility of MRI of [1-13C]fumarate metabolism using parahydrogen-induced polarization (PHIP), a low-cost alternative to dissolution dynamic nuclear polarization (dDNP), a cost-effective and high-yield synthetic pathway of hydrogenation precursor [1-13C]acetylenedicarboxylate (ADC) was developed. The trans-selectivity of the hydrogenation reaction of ADC using a ruthenium-based catalyst was elucidated employing density functional theory (DFT) simulations. A simple PHIP set-up was used to generate hyperpolarized [1-13C]fumarate at sufficient 13C polarization for ex vivo detection of hyperpolarized 13C malate metabolized from fumarate in murine liver tissue homogenates, and in vivo 13C MR spectroscopy and imaging in a murine model of acetaminophen-induced hepatitis. 相似文献
97.
Li T Garg U Liu Y Marks R Nayak BK Rao PV Fujiwara M Hashimoto H Kawase K Nakanishi K Okumura S Yosoi M Itoh M Ichikawa M Matsuo R Terazono T Uchida M Kawabata T Akimune H Iwao Y Murakami T Sakaguchi H Terashima S Yasuda Y Zenihiro J Harakeh MN 《Physical review letters》2007,99(16):162503
The strength distributions of the giant monopole resonance (GMR) have been measured in the even-A Sn isotopes (A=112-124) with inelastic scattering of 400-MeV alpha particles in the angular range 0 degrees -8.5 degrees . We find that the experimentally observed GMR energies of the Sn isotopes are lower than the values predicted by theoretical calculations that reproduce the GMR energies in 208Pb and 90Zr very well. From the GMR data, a value of Ktau = -550 +/- 100 MeV is obtained for the asymmetry term in the nuclear incompressibility. 相似文献
98.
Cover Picture: Two‐step Synthesis of Multi‐Substituted Amines by Using an N‐Methoxy Group as a Reactivity Control Element (Chem. Eur. J. 26/2014)
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99.
Back Cover: Amphiphilic Inclusion Spaces for Various Guests and Regulation of Fluorescence Intensity of 1,8‐Bis(4‐aminophenyl)anthracene Crystals (Chem. Eur. J. 11/2014)
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100.
Fast Epitope Mapping for the Anti‐MUC1 Monoclonal Antibody by Combining a One‐Bead‐One‐Glycopeptide Library and a Microarray Platform
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Dr. Fayna Garcia‐Martin Dr. Takahiko Matsushita Dr. Hiroshi Hinou Prof. Dr. Shin‐Ichiro Nishimura 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(48):15891-15902
Anti‐MUC1 monoclonal antibodies (mAbs) are powerful tools that can be used to recognize cancer‐related MUC1 molecules, the O‐glycosylation status of which is believed to affect binding affinity. We demonstrate the feasibility of using a rapid screening methodology to elucidate those effects. The approach involves i) “one‐bead‐one‐compound”‐based preparation of bilayer resins carrying glycopeptides on the shell and mass‐tag tripeptides coding O‐glycan patterns in the core, ii) on‐resin screening with an anti‐MUC1 mAb, iii) separating positive resins by utilizing secondary antibody conjugation with magnetic beads, and (iv) decoding the mass‐tag that is detached from the positive resins pool by using mass spectrometric analysis. We tested a small library consisting of 27 MUC1 glycopeptides with different O‐glycosylations against anti‐MUC1 mAb clone VU‐3C6. Qualitative mass‐tag analysis showed that increasing the number of glycans leads to an increase in the binding affinity. Six glycopeptides selected from the library were validated by using a microarray‐based assay. Our screening provides valuable information on O‐glycosylations of epitopes leading to high affinity with mAb. 相似文献