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1.
Under atmospheric pressure, methanol was produced from CO2–H2 over Pd/ZnO and from CO–H2 over Pd/MgO catalyst. Similar support effects were observed over Cu catalysts. 相似文献
2.
3.
Akinori Ohshita Masaaki Okuhara Chiharu Matsuya Koichi Hata Kazuo Iida 《Mikrochimica acta》2006,155(1-2):225-228
A new electron holographic method is presented to directly visualize pure phase objects such as electromagnetic microfields,
which is achieved by superposition of two kinds of electron holograms. The method is very simple and is twice as sensitive
as the conventional double-exposure electron holography and the four-electron-wave interference. Using this technique, an
electric field around a charged latex sphere and a magnetic field around a barium ferrite particle have been directly observed. 相似文献
4.
Kazuhiro Watanabe Noboru Akino Tetsuo Aoyagi Noboru Ebisawa Yukio Fujiwara Atsusi Honda Takashi Inoue Takao Itoh Mikito Kawai Minoru Kazawa Junichi Koizumi Masaaki Kuriyama Kenji Miyamoto Naoki Miyamoto Kazuhiko Mogaki Yoshihiro Ohara Tokumichi Ohga Yoshikazu Okumura Hiroshi Oohara Katsumi Ohshima Fujio Satoh Kazuhiko Shimizu Syunji Takahashi Hirotsugu Usami Katsutomi Usui Masahiro Yamamoto Takeshi Yamazaki 《Radiation Physics and Chemistry》1997,49(6):631-639
A negative-ion-based neutral beam injector (N-NBI) has been constructed for JT-60U. The N-NBI is designed to inject 500 keV, 10 MW neutral beams using two ion sources, each producing a 500 keV, 22 A D− ion beam. In the preliminary experiment using one ion source, a D− ion beam of 13.5 A has been successfully accelerated with an energy of 400 keV (5.4 MW) for 0.12 s at an operating pressure of 0.22 Pa. This is the highest D− beam current and power in the world. Co-extracted electron current was effectively suppressed to the ratio of Ie/ID− < 1. The highest energy beam of 460 keV, 2.4 A, 0.44 s has also been obtained. To realize 1 MeV class NBI system for ITER (International Thermonuclear Experimental Reactor), demonstration of ampere class negative ion beam acceleration up to 1 MeV is an important mile stone. To achieve the mile stone, a prototype accelerator and a 1 MV, 1 A test facility called MeV Test Facility (MTF) were constructed. Up to now, an H− ion beam was accelerated up to the energy of 805 keV with an acceleration drain current of 150 mA for 1 s in a five stage electrostatic multi-aperture accelerator. 相似文献
5.
Twenty one methyl 5-phenoxy-2-furancarboxylates prepared from the reaction of methyl 5-nitro-2-furan-carboxylate with phenoxides via displacement of the nitro group. In the reaction of potassium 2-nitrophen-oxide with methyl 5-nitro-2-furancarboxylate at 110°-120°, 2,2′-dinitrodiphenyl ether was obtained as a main product. 相似文献
6.
7.
Ikuta A Mizuta N Kitahata S Murata T Usui T Koizumi K Tanimoto T 《Chemical & pharmaceutical bulletin》2004,52(1):51-56
Six novel branched beta-cyclodextrins (betaCDs) having beta-D-galactose residues on the non-reducing terminal of the sugar side chains, namely 6(1),6(4)-di-O-(beta-D-galactosyl)-betaCD (10), 6-O-(beta-D-galactosyl)-betaCD (11), 6(1),6(4)-di-O-(beta-lactosyl)-betaCD (14), 6-O-(beta-lactosyl)-betaCD (15), 6(1),6(4)-di-O-(4'-O-beta-D-galactosyl-beta-lactosyl)-betaCD (18), and 6-O-(4'-O-beta-D-galactosyl-beta-lactosyl)-betaCD (19), were chemically synthesized using the trichloroacetimidate method. The reaction products were separated by HPLC on an amino column into dibranched and monobranched betaCDs. Their structures were confirmed by mass spectrometry (MS) and two-dimensional (2D) NMR spectroscopic analysis. To study the length of the sugar side chains attached to the CD ring, which leads to differences in the functions of the branched CDs, interactions of these compounds with peanut (Arachis hypogaea) agglutinin (PNA) were investigated using an optical biosensor and an inhibition assay based on hemagglutination. The results showed that all branched betaCDs interacted with PNA, and the binding affinity was 18>14>10 and 19>15>11 when the derivatives were compared on the basis of side chain length. 相似文献
8.
Murakami M Usui I Hasegawa M Matsuda T 《Journal of the American Chemical Society》2005,127(5):1366-1367
Cyclobutene, having a pinacolatoboryl group at the 3-position, was prepared by the reaction of trimethyl borate with a cyclobutenyl anion, which was generated by reductive lithiation of 3-(phenylselenyl)cyclobutene. Its thermal ring-opening reaction provided (Z)-1-borylbuta-1,3-diene selectively despite the arising steric congestion. The contrasteric behavior was accounted for by assuming an electron-accepting interaction of the vacant boron p orbital with the distorted breaking sigma orbital in the inward transition state. 相似文献
9.
Raman spectra of stilbene mono- and di-negative ions in tetrahydrofuran solution were obtained by Ar+ laser exciting lines. A considerable frequency shift was observed for several vibrations in the successive steps: stilbene → (stilbene)? → (stilbene)2?. The observed shift is discussed in a simple VB scheme, particularly in comparison with the results on anthracene negative ions. The resonance Raman effect was striking for both ions with intensity maxima at the exciting wavelengths close to the absorption maxima. 相似文献
10.
An unexpected product, 1-(4-ethoxycarbonylmethyl-5-nitro-2-furyl)-2-(2-furyl)-3-ethoxycarbonyl-indolizine was obtained by the reaction of α-(2-furyl)-β-(5-nitro-2-furyl)ethynyl with N-ethoxy-carbonylmethylpyridinium ylide in N,N-dimethylformamide, together with 1-(5-nitro-2-furyl)-2-(2-furyl)-3-ethoxycarbonylindolizine. 相似文献