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排序方式: 共有436条查询结果,搜索用时 15 毫秒
51.
Akiko Kumada Kunihiko Hidaka Kouji Amano Kohichi Itoh 《IEEJ Transactions on Electrical and Electronic Engineering》2009,4(2):297-299
A new effective processing for polychlorinated biphenyls (PCBs) has been recently developed. PCBs become harmless by dechlorination using 2.45 GHz-microwave (MW). To investigate such chemical reaction by MW irradiation, the dielectric loss of pure PCBs solutions and an isomer mixture in MW band is measured. Some PCBs and isopropyl alchol, added as a source of hydrogen supply have high dielectric loss in MW band. This suggests that MW heats PCBs and isopropyl alchol, and then the temperature of the solvent consisting mainly of insulating oil rises by the thermal conduction. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
52.
53.
Kyoko Hori Masahiro Fukuta Hirokazu Shimooka Shigemi Kohiki Toetsu Shishido Masaoki Oku Masanori Mitome Yoshio Bando 《Journal of Alloys and Compounds》2005,390(1-2):261-264
β-Ga2O3 nanocolumns straightened and crossed perpendicularly each other were deposited on MgO (1 0 0) substrate by vapor phase transport method. Growth of the nanocolumns was examined at steps of 1000, 1050, and 1200 °C in elevation of source-boat temperature. We have drawn out the substrate from deposition-tube at each source-boat temperatures of 1000, 1050, and 1200 °C. Scanning electron microscopy of the sample with source-boat temperature of 1200 °C demonstrated that the straightened and elongated nanocolumns are crossing perpendicularly each other. Typical lengths of the nanocolumns were in the range of several hundreds nanometers below 1050 °C, and those of 1200 °C were in the range of ten to fifteen hundreds nanometers. Diameters of the nanocolumns stayed in the range of few hundreds nanometers, notwithstanding variation of the source temperature. X-ray diffraction and transmission electron microscopy with energy dispersive X-ray spectroscopy revealed that the nanocolumns are monoclinic β-Ga2O3 crystal, and the (4 0 0) plane of β-Ga2O3 nanocolumns is parallel to the (1 0 0) plane of MgO substrate. 相似文献
54.
Satoshi Watanabe Shuji Ohsaki Akiko Fukuta Tatsuya Hanafusa Kento Takada Hideki Tanaka Taisuke Maki Kazuhiro Mae Minoru T. Miyahara 《Advanced Powder Technology》2017,28(11):3104-3110
Here we quantitatively evaluated the mixing performance of a tailor-made microreactor with central-collision type through the iodide/iodate chemical test reaction, and applied the microreactor to the synthesis of zeolitic imidazolate framework-8 (ZIF-8), which is a subclass of porous coordination polymers (PCPs) or metal organic frameworks (MOFs). The chemical test reaction demonstrated excellent mixing performance of the microreactor with a characteristic mixing time shorter than 1 ms, which is approximately 100 times faster than those of a batch reactor and a millimeter-sized Y-shaped mixer. Taking advantage of the rapid and uniform mixing, the microreactor successfully produced ZIF-8 particles with high reproducibility by simply mixing aqueous solutions of zinc nitrate and 2-methylimidazole. The synthesis at room temperature resulted in ZIF-8 particles with chamfered cube shape, while a lower temperature of 5 °C produced raspberry-type spherical particles. We confirmed that prepared ZIF-8 particles have BET surface area of ~1500 m2/g and exhibit the gate adsorption behavior caused by the structural transition of the ZIF-8 framework. 相似文献
55.
Automated Synthesis of (rac)‐, (R)‐, and (S)‐[18F]Epifluorohydrin and Their Application for Developing PET Radiotracers Containing a 3‐[18F]Fluoro‐2‐hydroxypropyl Moiety 下载免费PDF全文
Dr. Tomoteru Yamasaki Yiding Zhang Wakana Mori Dr. Masayuki Hanyu Katsushi Kumata Akiko Hatori Dr. Lin Xie Nobuki Nengaki Prof. Dr. Ming‐Rong Zhang 《ChemMedChem》2018,13(16):1723-1731
To introduce the 3‐[18F]fluoro‐2‐hydroxypropyl moiety into positron emission tomography (PET) radiotracers, we performed automated synthesis of (rac)‐, (R)‐, and (S)‐[18F]epifluorohydrin ([18F] 1 ) by nucleophilic displacement of (rac)‐, (R)‐, or (S)‐glycidyl tosylate with 18F? and purification by distillation. The ring‐opening reaction of (R)‐ or (S)‐[18F] 1 with phenol precursors gave enantioenriched [18F]fluoroalkylated products without racemisation. We then synthesised (rac)‐, (R)‐, and (S)‐ 2‐{5‐[4‐(3‐[18F]fluoro‐2‐hydroxypropoxy)phenyl]‐2‐oxobenzo[d]oxazol‐3(2H)‐yl}‐N‐methyl‐N‐phenylacetamide ([18F] 6 ) as novel radiotracers for the PET imaging of translocator protein (18 kDa) and showed that (R)‐ and (S)‐[18F] 6 had different radioactivity uptake in mouse bone and liver. Thus, (rac)‐, (R)‐, and (S)‐[18F] 1 are effective radiolabelling reagents and can be used to develop PET radiotracers by examining the effects of chirality on their in vitro binding affinities and in vivo behaviour. 相似文献
56.
Akiko Ishikura Akitoshi Mizuno Masahito Watanabe Tadahiko Masaki Takehiko Ishikawa Shinichi Yoda 《International Journal of Thermophysics》2008,29(6):2015-2024
BaGe alloys with two compositions near their eutectic point form open framework structures called the clathrate structure.
These BaGe compounds with the clathrate structure can be made by rapid solidification from their liquid state. However, the
formation mechanism of the clathrate structure has not been clarified due to lack of information on their liquid-state structure
and properties. Since BaGe alloy melts have very high reactivity, it is difficult to measure the thermophysical properties
of them by ordinary methods using a container. Therefore, a containerless technique must be used to measure the thermophysical
properties of BaGe melts. Using the electrostatic levitation (ESL) technique as a containerless technique, the thermophysical
properties (density, surface tension, and viscosity) of BaGe melts around the eutectic composition were measured in order
to clarify the formation mechanism of the clathrate structure, and also the structure of them was observed by using the high-energy
X-ray diffraction method combined with ESL. From experimental results, it was observed that the short-range order based on
the clathrate structure exists even in the liquid state at the clathrate-forming compositions. 相似文献
57.
Grgory Effantin Akiko Fujiwara Takeru Kawasaki Takashi Yamada Guy Schoehn 《International journal of molecular sciences》2021,22(20)
The ϕRSA1 bacteriophage has been isolated from Ralstonia solanacearum, a gram negative bacteria having a significant economic impact on many important crops. We solved the three-dimensional structure of the ϕRSA1 mature capsid to 3.9 Å resolution by cryo-electron microscopy. The capsid shell, that contains the 39 kbp of dsDNA genome, has an icosahedral symmetry characterized by an unusual triangulation number of T = 7, dextro. The ϕRSA1 capsid is composed solely of the polymerization of the major capsid protein, gp8, which exhibits the typical “Johnson” fold first characterized in E. coli bacteriophage HK97. As opposed to the latter, the ϕRSA1 mature capsid is not stabilized by covalent crosslinking between its subunits, nor by the addition of a decoration protein. We further describe the molecular interactions occurring between the subunits of the ϕRSA1 capsid and their relationships with the other known bacteriophages. 相似文献
58.
A technique for the measurement of the group refractive index wavelength dependence of optical materials using a low-coherence tandem interferometer and a spectrometer is proposed. Four channeled spectra resulting from interferences of light beams from different pairs of optical paths are used for the calculation of optical path differences. The group refractive index wavelength dependence is calculated from these optical path differences generated from the sample under measurement. No a priori information of the geometric thickness of a sample is required. The wavelength dependence of the group refractive index of the samples BK7 parallel plate of 5.200 and 10.025 mm from 675 to 850 nm is experimentally measured with an accuracy of the order of 10(-5) and a repeatability of the order of 10(-9). 相似文献
59.
Mitsuhiro Fukuta Tadashi Yanagisawa Masao Shimasaki Yasuhiro Ogi 《International Journal of Refrigeration》2006,29(7):1058-1065
The mixing of refrigeration oil with refrigerant in a refrigeration cycle has great influence on cycle performance. A sampling method is the most general way to measure the mixing ratio of refrigerant and refrigeration oil. Since the sampling method is time-consuming and reduces the amount of refrigerant and oil in the cycle, a real-time measurement is desirable. In this study, a refractive index measurement was applied to measure the mixing ratio of refrigerant/oil mixture. A laser displacement sensor was used to detect any change in optical path which results from changes of the refractive index of refrigerant/oil mixture. For the practical application of real-time measurement of the oil circulation ratio (OCR) in the refrigeration cycle, a correlation between the refractive index and the mixing ratio was developed. In addition, the changes of the refractive index in a range of a few percentages of the oil concentration and under subcooled conditions were measured. Finally, a transient measurement of the OCR in a practically operating refrigeration cycle was carried out successfully. 相似文献
60.
Andréas LyberisAdam J. Stevenson Akiko SuganumaSandrine Ricaud Frédéric DruonFrédéric Herbst Daniel VivienPatrick Gredin Michel Mortier 《Optical Materials》2012,34(6):965-968
In Yb:CaF2, the coordination of Yb3+ in the CaF2 lattice determines the spectroscopic properties that make Yb:CaF2 a good candidate for high power laser applications. In this work, we measure the optical absorption, emission, and fluorescence lifetime of 0.1, 1, 5, and 10 at% Yb:CaF2 ceramics to determine whether Yb3+ substitutes as hexamer clusters giving rise to the tenability and long fluorescent lifetime observed in Yb:CaF2 single crystals. Absorption and emission spectra show that the concentration of Yb3+ present in hexamer clusters, as opposed to isolated ions, increases with increasing Yb3+ content. Fluorescence lifetime also increases with increasing Yb3+ content. Laser testing on a 1 at% Yb:CaF2 transparent ceramic demonstrates that these materials are viable laser gain media. 相似文献