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81.
82.
Takashi Maoka Miho Takemura Harukuni Tokuda Nobutaka Suzuki Norihiko Misawa 《Tetrahedron letters》2014
In order to produce a novel keto-carotenoid in Escherichia coli, we introduced the marine bacterial carotenoid ketolase gene (crtW) into pathway-engineered E. coli producing carotenoids of plant origin, which carried the lycopene biosynthesis genes (crtE, crtB, and crtI) from soil bacterium Pantoea ananatis and the liverwort Marchantia polymorpha genes that encode lycopene β-cyclase (MpLCYb), lycopene ε-cyclase (MpLCYe), and β-carotenoid hydroxylase (MpBHY). A novel keto-carotenoid (1) was produced by these carotenoid biosynthesis genes in E. coli along with α-echinenone, adonirubin, and adonixanthin. The structure of 1 was determined as (3S,6′R)-3-hydroxy-β,ε-caroten-4-one based on Uv–vis, MS, 1H NMR, and CD spectral data. This compound was named 4-ketozeinoxanthin and showed anti-tumor-promoting activity. 相似文献
83.
K. N. Suzuki E. C. Machado W. Machado A. V. B. Bellido L. F. Bellido J. A. Osso Jr. R. T. Lopes 《Journal of Radioanalytical and Nuclear Chemistry》2014,299(1):357-361
Mangrove sediment cores sampled from Sepetiba Bay (SE Brazil) were covered with tidal water spiked with 75Se, 51Cr and 60Co to evaluate the removal efficiency of these radiotracers by underlying sediments. Variable time-evolution trends were observed along 115 h experiments, with significant differences between removal efficiencies of all radiotracers observed only after 70 h (51Cr > 60Co > 75Se). After an event of 60Co release back to overlying water, there was a general trend of lower 60Co removal than observed for other radiotracers during the period from 20 to 54 h. After this event, alternated periods of higher 60Co and higher 75Se removal trends were observed, attributed to behavioural differences expected for such anionic and cationic radiotracers. While 75Se and 51Cr showed uniform time-evolution curves, as typically found in the literature for most radiotracers, 60Co removal rates presented oscillations, probably due to sensitivity to changes in redox conditions within underlying sediments. Results evidenced the role of mangrove sediments as trace element sinks, which have implications for coastal water quality and for possible uses of such sediments in wastewater treatment systems. 相似文献
84.
We report the dependence of Brillouin linewidths on the pump power below the threshold of Brillouin lasing in a silica fiber. The Stokes Brillouin shift in a silica fiber is nearly unchanged, and its linewidth decreases with increasing pump power. However, the anti-Stokes Brillouin shift becomes smaller and its linewidth larger with increasing pump power. We explain these experimental results by the distributed fluctuating source model. 相似文献
85.
Kumar Samir Taneichi Taiga Fukuoka Takao Namura Kyoko Suzuki Motofumi 《Cellulose (London, England)》2021,28(17):10803-10813
Cellulose - Surface-enhanced Raman spectroscopy (SERS)-based biosensors have recently been extensively developed because of their high sensitivity and nondestructive nature. Conventional SERS... 相似文献
86.
N. Kuroda S. Ulmer D. J. Murtagh S. Van Gorp Y. Nagata M. Diermaier S. Federmann M. Leali C. Malbrunot V. Mascagna O. Massiczek K. Michishio T. Mizutani A. Mohri H. Nagahama M. Ohtsuka B. Radics S. Sakurai C. Sauerzopf K. Suzuki M. Tajima H. A. Torii L. Venturelli B. Wünschek J. Zmeskal N. Zurlo H. Higaki Y. Kanai E. Lodi Rizzini Y. Nagashima Y. Matsuda E. Widmann Y. Yamazaki 《Hyperfine Interactions》2015,235(1-3):13-20
In order to test CPT symmetry between antihydrogen and its counterpart hydrogen, the ASACUSA collaboration plans to perform high precision microwave spectroscopy of ground-state hyperfine splitting of antihydrogen atom in-flight. We have developed an apparatus (“cusp trap”) which consists of a superconducting anti-Helmholtz coil and multiple ring electrodes. For the preparation of slow antiprotons and positrons, Penning-Malmberg type traps were utilized. The spectrometer line was positioned downstream of the cusp trap. At the end of the beamline, an antihydrogen beam detector was located, which comprises an inorganic Bismuth Germanium Oxide (BGO) single-crystal scintillator housed in a vacuum duct and surrounding plastic scintillators. A significant fraction of antihydrogen atoms flowing out the cusp trap were detected. 相似文献
87.
88.
Katsumi Suzuki Asuki Toda Yingjie Liao Norihiko Kamata Zentaro Honda 《Molecular Crystals and Liquid Crystals》2015,621(1):124-128
We investigated crystallinity parameters and ordering domains of poly(3-hexylthiophene-2,5-diyl) blended in [6,6]-phenyl-C61-butyric acid methyl ester films, which were fabricated by pulsed electrospray deposition methods. The crystallinity parameter and the ordering domain were estimated from Raman and optical absorption spectra, respectively. As a result, they were improved with decreasing the off time of pulse voltage, corresponding to the slow evaporation speed of solvent. In addition, both the space-charge limited current mobility and the photoconversion efficiency showed same trend. A highest photoconversion efficiency of 1.11 % was achieved without the thermal annealing process after depositing the active layer. 相似文献
89.
Hiroyuki Nishide Takayuki Suzuki Yuji Soejima Eishun Tsuchida 《Macromolecular Symposia》1994,80(1):145-156
Facilitated or complexation-mediated transport of oxygen in the solid membrane containing a fixed carrier was described, by using the polymer-bound cobalt Schiff's base chelate (CoS) and cobaltporphyrin (CoP). α3 β-Substituted cobaltporphyrin derivatives were synthesized: The oxygen-binding reaction to cobalt was affected by the cavity structure on porphyrin, i.e., unbulky amido-substituted groups such as acetylamido- and acrylamido-substituents enhanced oxygen-binding and -dissociation rate constant or provided an oxygen-binding pathway. Oxygen transport through the membranes of these polymer-bound CoP derivatives was selectively augmented due to the rapid and reversible oxygen-binding. Diffusion constants via the fixed CoPs correlated to the characteristics of oxygen-binding reaction. 相似文献
90.
Funakawa Daiju Matsuzawa Yasumichi Sasaki Itaru Suzuki Akito Teranishi Noriaki 《Letters in Mathematical Physics》2020,110(9):2471-2490
Letters in Mathematical Physics - We study time operators for discrete-time quantum systems. Quantum walks are typical examples. We construct time operators for one-dimensional homogeneous quantum... 相似文献