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111.
Jun‐ichi Tamura Akihiro Yamaguchi Junko Tanaka Yuko Nishimura 《Journal of carbohydrate chemistry》2013,32(2):61-82
We have synthesized, for the first time, the partial sequence of the betaglycan composed of the tetraosyl hexapeptide, which was directly usable as a probe for enzymatic glycosyl transfer. Stepwise elongation afforded the corresponding tetraosyl trichloroacetimidate. The common glycosyl dipeptide:[β‐d‐GlcA‐(1→3)‐β‐d‐Gal‐(1→3)‐β‐d‐Gal‐(1→4)‐β‐d‐Xyl‐(1→O)‐Ser‐Gly] was synthesized by glycosylation of the corresponding tetraosyl trichloroacetimidate and Ser‐Gly moiety. The glycosyl dipeptide was coupled with other core peptide parts in solution phase and on a solid support. These glycosyl hexapeptides were then transformed into the desired target compounds. 相似文献
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113.
Yasuo Kameda Takuya Miyazaki Toshiya Otomo Yuko Amo Takeshi Usuki 《Journal of solution chemistry》2014,43(9-10):1588-1600
Neutron diffraction measurements were carried out at 25 °C for aqueous LiNO3 heavy water solutions, (*LiNO3) x (D2O)1?x where x = 0.1, 0.05 and 0.01, in which the 6Li/7Li isotopic ratios were varied. Structural information on intermolecular nearest neighbor Li+···D2O interactions in the extensive concentration range was derived from the first-order difference function, ?Li(Q), obtained from the difference in scattering cross sections between 6Li- and 7Li-enriched sample solutions. The nearest neighbor Li+···O distance and coordination number for sample solution with x = 0.1 were determined to be r LiO = 1.969 (8) Å and n LiO = 4.12 (6), respectively, corresponding to the four-coordinated Li+ ion in the solution. On the other hand, those obtained for the solution with x = 0.01 are r LiO = 2.00 (2) Å and n LiO = 6.0 (2), respectively, indicating that hexaaqua Li+ is dominant in the dilute solution. These results clearly indicate that a concentration dependence of the hydration number of Li+ occurs in the aqueous solutions. 相似文献
114.
Tomoyoshi Ono Yuki Moribe Shunsuke Takashima Ikuo Ichinose Tetsuo Matsui Kazuhiko Sakakibara 《Nuclear Physics B》2007
We introduce a U(1) lattice gauge theory with dual gauge fields and study its phase structure. This system is partly motivated by unconventional superconductors like extended s-wave and d -wave superconductors in the strongly-correlated electron systems and also studies of the t–J model in the slave-particle representation. In this theory, the “Cooper-pair” (or RVB spinon-pair) field is put on links of a cubic lattice due to strong on-site repulsion between original electrons in contrast to the ordinary s -wave pair field on sites. This pair field behaves as a gauge field dual to the U(1) gauge field coupled with the hopping of electrons or quasi-particles of the t–J model, holons and spinons. By Monte Carlo simulations we study this lattice gauge model and find a first-order phase transition from the normal state to the Higgs (superconducting) phase. Each gauge field works as a Higgs field for the other gauge field. This mechanism requires no scalar fields in contrast to the ordinary Higgs mechanism. An explicit microscopic model is introduced, the low-energy effective theory of which is viewed as a special case of the present model. 相似文献
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116.
Inagaki Makoto Sekimoto Shun Tadokoro Takahiro Ueno Yuichiro Kani Yuko Ohtsuki Tsutomu 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(2):681-686
Journal of Radioanalytical and Nuclear Chemistry - Amount estimation of production of 99Mo required for medical applications was carried out by utilizing an electron linear accelerator with... 相似文献
117.
Luis K. Ono Shengzhong Liu Yabing Qi 《Angewandte Chemie (International ed. in English)》2020,59(17):6676-6698
In several photovoltaic (PV) technologies, the presence of electronic defects within the semiconductor band gap limit the efficiency, reproducibility, as well as lifetime. Metal halide perovskites (MHPs) have drawn great attention because of their excellent photovoltaic properties that can be achieved even without a very strict film‐growth control processing. Much has been done theoretically in describing the different point defects in MHPs. Herein, we discuss the experimental challenges in thoroughly characterizing the defects in MHPs such as, experimental assignment of the type of defects, defects densities, and the energy positions within the band gap induced by these defects. The second topic of this Review is passivation strategies. Based on a literature survey, the different types of defects that are important to consider and need to be minimized are examined. A complete fundamental understanding of defect nature in MHPs is needed to further improve their optoelectronic functionalities. 相似文献
118.
Yoshitomo Ono Naoyuki Kawashima Hiroto Kudo Tadatomi Nishikubo Takabumi Nagai 《Journal of polymer science. Part A, Polymer chemistry》2005,43(19):4412-4421
The ring‐opening copolymerization of donor–acceptor norbornadiene (D–A NBD) dicarboxylic acid monoglycidyl ester derivatives with D–A NBD dicarboxylic acid anhydride was performed with tetraphenylphosphonium bromide as a catalyst in toluene to produce new norbornadiene (NBD) polyesters containing D–A NBD moieties in the main chain and in the side chain in one step in good yields. The photoisomerization of the D–A NBD moieties in these polyesters proceeded very smoothly to give the corresponding quadricyclane groups. Because these NBD polyesters contained many NBD moieties in the polymer chain, they had the highest capacity for heat storage in the D–A NBD polymers reported so far. The stored thermal energy of the irradiated polyesters was evaluated by differential scanning calorimetry analysis to be approximately 150–190 J/g. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4412–4421, 2005 相似文献
119.
A survey of metabolic changes in potato leaves by NMR‐based metabolic profiling in relation to resistance to late blight disease under field conditions
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Satoru Tomita Seishi Ikeda Shogo Tsuda Nobutaka Someya Kenji Asano Jun Kikuchi Eisuke Chikayama Hiroshi Ono Yasuyo Sekiyama 《Magnetic resonance in chemistry : MRC》2017,55(2):120-127
Non‐targeted nuclear magnetic resonance (NMR)‐based metabolic profiling was applied to potato leaves to survey metabolic changes associated with late blight resistance under field conditions. Potato plants were grown in an experimental field, and the compound leaves with no visible symptoms were collected from 20 cultivars/lines at two sampling time points: (i) the time of initial presentation of symptoms in susceptible cultivars and (ii) 12 days before this initiation. 1H NMR spectra of the foliar metabolites soluble in deuterium oxide‐ or methanol‐d4‐based buffers were measured and used for multivariate analysis. Principal component analysis for six cultivars at symptom initiation showed a class separation corresponding to their levels of late blight resistance. This separation was primarily explained by higher levels of malic acid, methanol, and rutin and a lower level of sucrose in the resistant cultivars than in the susceptible ones. Partial least squares regression revealed that the levels of these metabolites were strongly associated with the disease severity measured in this study under field conditions. These associations were observed only for the leaves harvested at the symptom initiation stage, but not for those collected 12 days beforehand. Subsequently, a simple, alternative enzymatic assay for l ‐malic acid was used to estimate late blight resistance, as a model for applying the potential metabolic marker obtained. This study demonstrated the potential of metabolomics for field‐grown plants in combination with targeted methods for quantifying marker levels, moving towards marker‐assisted screening of new cultivars with durable late blight resistance. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
120.
Haino T Yamanaka Y Araki H Fukazawa Y 《Chemical communications (Cambridge, England)》2002,(5):402-403
The metal-induced regulation of fullerene complexation with double-calix[5]arene is described. The receptor shows strong binding to C70 only in the presence of Cu+. 相似文献