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51.
Kozo Matsumoto Aritaka Matsunami Hiroyuki Oyama Kuniyuki Kitagawa 《Microchemical Journal》2005,81(2):195-200
For the detection of inorganic species, we have developed chemical reaction laser desorption ionization mass spectrometry, and applied it to the analysis of metal oxides in different oxidation states. Metal oxide species insoluble in common organic solvents were finely grounded in a mortar and suspended in a solvent. The turbid suspension was placed on a sample holder on which a suitable chelating reagent had been previously spotted in a similar manner for sample preparation employed in the matrix-assisted laser desorption mass spectrometry (MALDI-MS). By using this method, the mass spectra of manganese (II and IV) oxides (MnO and MnO2), cobalt (II and III) oxides (CoO and Co2O3), and chromium (III and VI) oxides (Cr2O3 and CrO3) were successfully obtained. By adjusting the experimental conditions, such as ionization modes and chelating reagents, the non-identical mass spectra were obtained for the elements in the different oxidation state. Thus, the oxidation states could be identified clearly. 相似文献
52.
Masakazu Nishida Yoshio Hayakawa Masaki Matsui Katsuyoshi Shibata Hiroshige Muramatsu 《Journal of heterocyclic chemistry》1992,29(1):113-116
Diels-Alder reaction of 2,5-dialkyl-3,4-bis(trifluoromethyl)furan with hexafluoro-2-butyne gave 1,4-dialkyl-7-oxa-2,3,5,6-tetrakis(trifluoromethyl)bicyclohepta-2,5-diene. Irradiation (uv) of 1,4-diethyl-7-oxa-2,3,5,6-tetrakis(trifluoromethyl)bicyclohepta-2,5-diene afforded 1-ethyl-2,3,4,5-tetrakis(trifluoromethyl)-1,4-cyclopentadiene, ethyl 3-[l-ethyl-2,3,4,5-tetrakis(trifluoromethyl)-1,4-cyclopentadienyl] ketone, and 2,7-diethyl-3,4,5,6-tetrakis(trifluoromethyl)oxepin. 相似文献
53.
Masakazu Nishida Yoshio Hayakawa Masaki Matsui Katsuyoshi Shibata Hiroshige Muramatsu 《Journal of heterocyclic chemistry》1991,28(2):225-229
The addition reaction of propionaldehyde to hexafluoro-2-butyne ( 1 ) under γ-ray irradiation gave trans-6,6,6-trifluoro-4-trifluoromethyl-4-hexen-3-one ( 2 ) and 4,5-bis(trifluoromethyl)octa-3,6-dione ( 3 ). The latter compound was treated with sulfuric acid to give 2,5-diethyl-3,4-bis(trifluoromethyl)furan ( 4a ). Several reactions, such as bromination, dehydrobromination and oxidation, were carried out to prepare derivatives of 4a . 相似文献
54.
H Ueki Y Matsunami A Motoshima T Funakoshi S Shoji Y Kubota 《Chemical & pharmaceutical bulletin》1984,32(11):4539-4544
55.
Ruth Knibbe Kazuhiro Nogita John Drennan Tsuneyuki Noguchi Katsuyoshi Tatenuma Pou Liu Fumihito Arai Eiji Yashima Michiru Nishiwaki Shigeki Kato 《Journal of nanoparticle research》2007,9(6):1201-1204
Multi-wall carbon nanotubes (MWNTs) have a great commercial potential as electron field emitters, but suffer from fundamental
problems such as stability and brightness. By depositing the MWNTs with nano-sized ruthenium dioxide (RuO2) particles, a new high performance emitter has been developed. When compared to MWNTs, the MWNTs impregnated with 1–2 nm
sized RuO2 have superior and more efficient electrical characteristics. MWNTs supported by a silicon substrate showed a reduction in
the onset voltage from 5.4 to 4 V/μm after RuO2 impregnation. The long-term stability of the impregnated MWNTs is also demonstrated with only a 20% increase in applied voltage
required after 700 h operation at 40 mA/cm2. 相似文献
56.
H Ueki K Furuta T Funakoshi Y Matsunami Y Kubota 《Chemical & pharmaceutical bulletin》1982,30(3):1054-1058
57.
A careful investigation of the Pt(111) surface has been carried out, using the MeV heliumscattering technique. The anomalously large surface relaxation effect reported previously has been identified as an experimental artifact resulting from an unexpectedly large surface damage effect at low temperature. Optimum conditions have been established for minimizing the main experimental sources of error: background subtraction, radiation damage, and deviations from the Rutherford scattering law. Using these optimum conditions, a series of scattering measurements has been made over the temperature range 40–300 K. At all temperatures, we observe a significant anisotropy in the 〈111〉 angular scans, indicating an outward relaxation of the Pt(111) surface plane. By comparing this observed anisotropy with a set of Monte Carlo simulations, a value of 0.03 ? 0.01 Å (i.e. 1.3 ? 0.4%) is obtained for the surface relaxation. The temperature dependence of the surface peak also indicates that the enhanced vibrational amplitude of the surface atoms is not nearly as large as had been derived previously from high-temperature LEED studies. 相似文献
58.
A new emission band has been found in alkali halides under high density excitation produced by heavy ion bombardments and is suggested to be arised from the recombination of bi-excitons. 相似文献
59.
MeV He+ ion backscattering has been used to show that the phase transition on a Pt(100) surface involves the lateral displacement of an entire plane of atoms. It is further shown that the outward relaxation of the unreconstructed surface plane is negligible, i.e. 0.5 ± 0.5% of thebulk interplanar spacing. 相似文献
60.