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排序方式: 共有470条查询结果,搜索用时 31 毫秒
1.
Shoraku Ryu Kazuo Furihata Masanori Koda Feifei Wei Takuya Miyakawa Masaru Tanokura 《Magnetic resonance in chemistry : MRC》2016,54(3):213-221
Japanese persimmon (Diospyros kaki L.) is recognized as an outstanding source of biologically active compounds relating to many health benefits. In the present study, NMR spectroscopy provided a comprehensive metabolic overview of Japanese persimmon juice. Detailed signal assignments of Japanese persimmon juice were carried out using various 2D NMR techniques incorporated with broadband water suppression enhanced through T1 effects (BB‐WET) or WET sequences, and 26 components, including minor components, were identified. In addition, most components were quantitatively evaluated by the integration of signals using conventional 1H NMR and BB‐WET NMR. This is the first detailed analysis combined with quantitative characterization of chemical components using NMR for Japanese persimmon. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
2.
Haptoglobin (Hp) is a hemoglobin-binding serum glycoprotein. Some variations in the Hp gene (HP) or Hp-related gene (HPR), including a single-nucleotide polymorphism in intron 2 of HRP, rs2000999, and a complete deletion of the HP gene (HPdel), one of the rare variants of HP, have been reported to correlate with the serum cholesterol concentration as well as the serum Hp concentration. In this study, we developed a duplex dual-labeled fluorescence probe-based method to simultaneously determine the rs2000999 G > A polymorphism by melting curve genotyping and the zygosity of HPdel by endpoint genotyping. This method was then validated by using the genomic DNA from 94 Japanese subjects for whom genotypes of rs2000999 and HPdel zygosity had already been determined. The results obtained with this method were in perfect agreement with the previous ones. Thus, the present method enables us to estimate these two polymorphisms in relatively large-scale groups of subjects, especially in Asian populations where the HPdel is distributed. 相似文献
3.
Reaction modes of n-butylmagnesium bromide with α,β-unsaturated esters, ketones, and nitriles were investigated in ether under anionic polymerization conditions. n-Butane and conjugate addition products observed were with all the monomers examined, but carbonyl addition products were not detected except with the unsaturated esters. Product distribution depends mainly upon reaction temperature and the concentration of the Grignard reagent, not upon the concentration of the unsaturated compounds. n-Butyl-magnesium bromide etherate in toluene gave similar results. 相似文献
4.
The effects of crosslinking on PVC are well known in regard to the improvement of mechanical properties, creep behavior, and softening temperature. Little is known, however, on the application of the PVC-crosslinking reaction, because most of crosslinked PVC tends to color easily at elevated temperatures. In this paper, a novel PVC-crosslinking reaction with 2-R-4,6-dithiol-s-triazine (I) has been presented to obtain insoluble products which hardly color on ageing. The reaction rate and induction period of the crosslinking reaction with I are made controllable by selecting the basicity of the substituent R of I as well as that of an acid acceptor in the blends. The utility of I as stabilizer as well as a crosslinking agent is also emphasized. 相似文献
5.
Dr. Chunlin Chen Prof. Zhongchang Wang Dr. Mitsuhiro Saito Dr. Tetsuya Tohei Prof. Yoshiro Takano Prof. Yuichi Ikuhara 《Angewandte Chemie (International ed. in English)》2014,53(6):1543-1547
Atomic‐resolution imaging of beam‐sensitive biominerals is extremely challenging, owing to their fairly complex structures and the damage caused by electron irradiation. Herein, we overcome these difficulties by performing aberration‐corrected electron microscopy with low‐dose imaging techniques, and report the successful direct atomic‐resolution imaging of every individual atomic column in the complex fluorapatite structure of shark tooth enameloid, which can be of paramount importance for teeth in general. We demonstrate that every individual atomic column in shark tooth enameloid can be spatially resolved, and has a complex fluorapatite structure. Furthermore, ab initio calculations show that fluorine atoms can be covalently bound to the surrounding calcium atoms, which improves understanding of their caries‐reducing effects in shark teeth. 相似文献
6.
The China Spallation Neutron Source/Rapid Cycling Synchrotron (CSNS/RCS) accelerates a high-intensity proton beam from 80 MeV to 1.6 GeV. Since the beam current and beam power is high, the beam loading is a severe problem for the stability of the circulating beam in the RCS. To study the beam loading effect in the CSNS/RCS theoretically, the RLC circuit model of the rf cavity, the method of Fast Fourier Transform and the method of Laplace transform have been employed to obtain the impedance of the rf system, the beam spectrum and the beam-induced voltage, respectively. Based on these physical models, the beam dynamics equations have been revised and a beam loading model has been constructed in the simulation code ORIENT. By using the code, the beam loading effect on the rf system of the CSNS/RCS has been investigated. Some simulation results have been obtained and conclusions have been drawn. 相似文献
7.
A remarkable effect of ionic liquids in transition-metal-free aerobic oxidation of benzylic alcohols
Yoshiro OdaKoji Hirano Tetsuya SatohSusumu Kuwabata Masahiro Miura 《Tetrahedron letters》2011,52(41):5392-5394
The transition-metal-free aerobic oxidation of benzylic alcohols is uniquely accelerated by a 1-butyl-3-methylimidazolium hexafluorophosphate (BMI-PF6)/PhCF3 biphasic system and Cs2CO3 to afford the corresponding ketones in good yields. The reaction system is also applicable to an oxidative cross-esterification of primary benzyl alcohols with a higher aliphatic alcohol. 相似文献
8.
Yoshiro Masuyama Kazuki YoshikawaNoriyuki Suzuki Kenji HaraAtsushi Fukuoka 《Tetrahedron letters》2011,52(51):6916-6918
Copper(II)-exchanged hydroxyapatite, prepared by ion-exchanging of Ca(II) in calcium hydroxyapatite [Ca10(PO4)6(OH)2] with Cu(NO3)2 at 70 °C in water, functions as a reusable heterogeneous catalyst with neither reducing agents nor bases for azide-alkyne [3+2] cycloaddition at 50 °C in water under air. 相似文献
9.
Experimental detection of proteolytic activity in a signal peptide peptidase of Arabidopsis thaliana
Hoshi Masako Ohki Yu Ito Keisuke Tomita Taisuke Iwatsubo Takeshi Ishimaru Yoshiro Abe Keiko Asakura Tomiko 《BMC biochemistry》2013,14(1):1-8
Background
The ubiquitin ligase COP1, COnstitutively Photomorphogenic 1, functions in many biological responses in mammalian cells, but its downstream pathway remains unclear.Results
Here, we identified FIP200, a key regulator of mammalian autophagy, as a novel COP1-interacting protein by yeast two-hybrid screening. The interaction was confirmed by a GST-pulldown assay. Split-GFP analysis revealed that interaction between COP1 and FIP200 predominantly occurred in the cytoplasm and was enhanced in cells treated with UV irradiation. Different forms of FIP200 protein were expressed in cultured mammalian cells, and ectopic expression of COP1 reduced one of such forms.Conclusions
These data suggest that COP1 modulates FIP200-associated activities, which may contribute to a variety of cellular functions that COP1 is involved in. 相似文献10.
Magnetic alloy(MA)-loaded cavities have been widely used in compact proton and heavy-ion synchrotrons,and the MA core is the key issue in their development.Chinese-produced MA has never yet been adopted as core material for an MA-loaded cavity.To use Chinese-produced MA as the core material,it is necessary to study its properties,and compare with MA material produced elsewhere.In this paper,the properties of several MA cores made of Chinese-produced material are measured.Based on the measured results,a schematic design is produced for a cavity which could obtain 1 kV gap voltage with less than 1.5 kW power dissipation in the frequency range of0.5-7 MHz.The difference between resonant frequencies obtained from simulation and analytical results is less than10%. 相似文献