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1.
Sohei Okazaki Noriaki Okazaki Hidetaka Sugaya Ryota Takahashi Yuji Matsumoto Hideomi Koinuma Tetsuya Hasegawa 《Applied Surface Science》2006,252(7):2615-2621
We developed a scanning microwave microscope (SμM) designed for high-throughput electric-property screening as well as for rapid construction of electronic phase diagrams at low temperatures. As a sensor probe, we used a high-Qλ/4 coaxial cavity resonator to which a thin needle with ball-tip end was attached. The sensor module was mounted on the low-temperature XYZ stage, which allowed us to map out the change of resonance frequency and quality factor due to the local tip-sample interaction at low temperatures. From the measurements of combinatorial thin films, such as Ti1−xCoxO2−δ and Nd0.9Ca0.1Ba2Cu3O7−δ (NCBCO), it was demonstrated that this SμM system has enough performance for the high-throughput characterization of sample conductance under variable temperature conditions. 相似文献
2.
3.
Simple modules over the Leibniz pairs are studied. Simple Poisson modules over Poisson algebras of the semisimple associative algebra structure are determined and they are nothing but simple bimodules over simple associative algebras with standard noncommutative Poisson algebra structure. 相似文献
4.
Toshiaki Asakai Ryota Minegishi Norie Inaba Yutaka Ishimura Mariko Murayama Tatsuhiko Tanaka 《Analytical sciences》2006,22(3):461-463
The drying conditions for primary standards of volumetric analysis have a significant effect on the titration results due to changes in the purity, stability and homogeneity. Amidosulfuric acid, a strong acid used as a reference material for volumetric analysis in Japan, was dried in a vacuum desiccator or heated at different temperatures, and then measured by Karl-Fischer titration, thermogravimetry/mass spectroscopy (TG-MS), ion chromatography and coulometric titration. The optimum drying conditions were at 50 degrees C for 24 h with crushing. 相似文献
5.
Uesato S Taniuchi K Kumagai A Nagaoka Y Seto R Hara Y Tokuda H Nishino H 《Chemical & pharmaceutical bulletin》2003,51(12):1448-1450
In the course of an exploratory investigation of antitumor-promoting catechins, 3-O-acyl-(+)-catechins of varying carbon lengths from C(4) to C(18) were assessed for inhibitory effects on the activation of the Epstein-Barr virus early antigen. Like 3-O-acyl-(-)-epigallocatechins, the (+)-catechin derivatives showed promising effects with the C-3 acyl chain of C(8)-C(11) carbon atoms. 相似文献
6.
Hidetake Sakuraba Yoshio Tananaka Fujio Toda 《Journal of inclusion phenomena and macrocyclic chemistry》1991,11(2):195-204
The asymmetric Michael addition of aromatic thiols to 2-cyclohexenone and maleic acid esters has been carried out by utilizing their crystalline cyclodextrin complexes suspended in water. The best chiral induction, 30% enantiomeric excess (ee), was achieved in combinations of 2-cyclohexenone and octyl maleate with the crystalline -cyclodextrin complex of benzenethiol (method A) to afford (S)-3-phenylthiocyclohexanone and (S)-octyl-2-phenylthiosuccinate, respectively, whereas the reaction of benzenethiol with 2-cyclohexenone included in -cyclodextrin (method B) inversely induced the chiral recognition to give the (R)-adduct with 4–9% ee. 相似文献
7.
Muliadi Ramli Nasrullah Idris Kenichi Fukumoto Hideaki Niki Fujio Sakan Tadashi Maruyama Koo Hendrik Kurniawan Tjung Jie Lie Kiichiro Kagawa 《Spectrochimica Acta Part B: Atomic Spectroscopy》2007,62(12):1379-1389
A TEA CO2 laser (350 mJ–1.5 J, 10.6 μm, 200 ns, 10 Hz) was focused onto a metal sub-target under He as host gas at 1 atmospheric pressure with a small amount of impurity gas, such as water and ethanol vapors. It was found that the TEA CO2 laser with the help of the metal sub-target is favorable for generating a strong, large volume helium gas breakdown plasma at 1 atmospheric pressure, in which the helium metastable-excited state was then produced overwhelmingly. While the metal sub-target itself was never ablated. The helium metastable-excited state produced after the strong helium gas breakdown plasma was considered to play an important role in exciting the atoms. This was confirmed by the specific characteristics of the detected H emission, namely the strong intensity with low background, narrow spectral width, and the long lifetime. This technique can be used for gas and solid samples analysis. For nonmetal solid analysis, a metal mesh was introduced in front of the nonmetal sample surface to help initiation of the helium gas breakdown plasma. For metal sample, analysis can be carried out by combining the TEA CO2 laser and an Nd–YAG laser where the Nd–YAG laser is used to ablate the metal sample. The ablated atoms from the metal sample are then sent into the region of helium gas breakdown plasma induced by the TEA CO2 laser to be excited through the helium metastable-excited state. This technique can be extended to the analysis of other elements, not limited only to hydrogen, such as halogens. 相似文献
8.
Kojima Kunihiko Miyazaki Mitsuharu Mizukami Fujio Maeda Kazuyuki 《Journal of Sol-Gel Science and Technology》1997,8(1-3):77-81
The structure of iron oxide was controlled by regulating the hydrolytic polymerization of aquo iron complexes with organic
polydentate ligands such as diols. Iron oxides were prepared by calcining the precursor polymers obtained from iron nitrate
nonahydrate and diols. When the diols were 1,2-pentanediol, 1,2-hexanediol and 1,2-octanediol, α-Fe2O3 with corundum structure appeared exclusively or as the main crystalline phase, in spite of the amount of diol used and the
calcination temperature. In the case of 1,2-decanediol and 1,2-dodecanediol, when five moles of the diols were used to one
mole of iron nitrate and the calcination temperatures were below 400°C, ψ-Fe2O3 with spinel structure appeared as the main phase and, when less than five moles of the diols were used, α-Fe2O3 appeared exclusively or as the main phase, irrespective of the calcination temperature. This tendency was also observed in
thin films. Thus, a transparent magnetic film composed of γ-Fe2O3 could be prepared by applying a benzene solution of the iron polymer, obtained with 5 equivalents of 1,2-decanediol, on quartz
and calcining the gel film at 350°C. 相似文献
9.
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
10.
It was confirmed that the rhenium complex, ReBr(CO)5, catalyzed the allylation of aldehydes with allyltributylstannane to give the corresponding homoallylic alcohols in moderate to good yields. Similarly, the reaction of aldehydes with enol silyl ether was efficiently promoted by the rhenium catalyst to afford the corresponding β-hydroxy carbonyl compounds. 相似文献