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531.
532.
The integrated density of states (IDS) for the Schr?dinger operators is defined in two ways: by using the counting function
of eigenvalues of the operator restricted to bounded regions with appropriate boundary conditions or by using the spectral
projection of the whole space operator. A sufficient condition for the coincidence of the two definitions above is given.
Moreover, a sufficient condition for the coincidence of the IDS for the Dirichlet boundary conditions and the IDS for the
Neumann boundary conditions is given. The proof is based only on the fundamental items in functional analysis, such as the
min-max principle, etc.
Received August 26, 1999; in final form February 21, 2000 / Published online February 5, 2001 相似文献
533.
Toshiaki Tatsukawa Akitaka Doi Masato Teranaka Hitoshi Takashima Fuminori Goda Seishiro Watanabe Toshitaka Idehara Tomohiro Kanemaki Tunetoyo Namba 《International Journal of Infrared and Millimeter Waves》2005,26(4):591-606
Microwave invasion into living bodies through a millimeter wave catheter irradiation is described. As radiation sources for millimeter wave irradiation tests both Impatt oscillator (IO) and a Gunn oscillator were used. Irradiated samples are cow livers and living rats. A newly designed wave-guide vent antenna (WVA) with an anti-reflecting layer (ARL) is used as a launcher for the irradiation and the reflectance measurements. The correlation between the denaturation of the
tissue and the reflectance from the WVA is studied in detail. 相似文献
534.
Irina D. Gocheva Ichiro Tanaka Takayuki Doi Shigeto Okada Jun-ichi Yamaki 《Electrochemistry communications》2009,11(8):1583-1585
The electrochemical properties of iron oxyfluoride of the Fe2OF4 type were investigated. The material exhibits a working potential at 3.0 V with a capacity of 200 mAh/g and cyclic reversibility in the range of 1.5–4.5 V. X-ray photoelectron spectroscopy (XPS) investigation of discharged material showed that iron was reduced to the divalent state. In this study, we report that Fe2OF4 material incorporates 1.4 Li per formula unit. 相似文献
535.
S. Matsunuma T. Inoue T. Doi T. Matsuu A. Hashimoto H. Fujiura S. Nakagawa 《Journal of magnetism and magnetic materials》2008
Sputtered tape media of a CoPtCr–SiO2 magnetic layer with a Ru underlayer was fabricated on a thin Aramid film by a facing targets sputtering (FTS) system at room temperature with no cooling. Transition electron microscope (TEM) images show columnar epitaxial growth of hcp-CoPtCr(1 0 0) plane on hcp-Ru(1 0 0). Average grain diameter of 10.2 nm with dispersion of 20.2% was obtained from TEM images. Enrichment of Co and Pt inside grains and segregation of Cr and Si to boundary were confirmed by point energy dispersive spectroscopy (EDS) measurements. Playback performance test on sputtered sample indicated that SNR is higher and PW50 value is lower than that of commercial coated tapes. These good playback properties could come from fine and isolated grain structure of magnetic layer of sputtered sample, as observed by TEM. 相似文献
536.
T. Matsuu A. Hashimoto H. Fujiura S. Matsunuma T. Inoue T. Doi S. Nakagawa 《Journal of magnetism and magnetic materials》2008
Ru/CoPtCr-SiO2 bilayer prepared at 4 and 26 mTorr of Ar gas pressure for the deposition of Ru and CoPtCr-SiO2 layers, respectively, exhibits better magnetic properties suitable for perpendicular magnetic recording media when they are deposited at room temperature on a Pt seed layer prepared at 450 °C. The Ru-O seed layer fabricated by a reactive sputtering method improves the Ru (0 0 1) texture deposited on a Ru-O layer. The Ru-O/Ru hybrid type of underlayer causes the improvement of the c-axis orientation of CoPtCr crystallites in the CoPtCr-SiO2 layer deposited on it. Fine granulation of magnetic grains in the CoPtCr-SiO2 layer is also attained when they are deposited on the Aramid type of flexible tape substrates. 相似文献
537.
Yamana K Fukunaga Y Ohtani Y Sato S Nakamura M Kim WJ Akaike T Maruyama A 《Chemical communications (Cambridge, England)》2005,(19):2509-2511
A pyrene-excimer-forming probe allowed the easy and sensitive detection of a single base mismatch in target DNA. This was due to the faster strand exchange rate compared to a fully-matched target. 相似文献
538.
Takeya T Kondo H Otsuka T Doi H Okamoto I Kotani E 《Chemical & pharmaceutical bulletin》2005,53(2):199-206
We investigated the reactions of various 1-naphthols (NPOHs; 1) with p-benzoquinones (Qs), such as 1,4-benzoquinone (BQ) and p-chloranil (CA), as pi-electron acceptors. With electron-rich NPOHs 1a-c, oxidative biaryl coupling and subsequent dehydrogenation reaction took place selectively to give the corresponding 2,2'-binapthyl-1,1'-quinones 3a-c in excellent yield. In the case of electron-deficient NPOHs 1e, f, two different types of reactions occurred in the presence of SnCl4 and ZrO2 under similar conditions: SnCl4 mediated oxidative dimerization and trimerization of NPOH, while ZrO2 promoted electrophilic arylation of Qs with NPOH. The resulting products 3 would be useful synthetic intermediates for naturally occurring diosindigo B, biramentaceone and violet-quinone. 相似文献
539.
540.
Qun Chen Takeyoshi Yamada Hiromichi Kurosu Isao Ando Takeshi Shiono Yoshiharu Doi 《Journal of Polymer Science.Polymer Physics》1992,30(6):591-601
The 13C spin-lattice relaxation times T1 of 13C-labeled polyethylene crystallized under different conditions were measured at temperatures from ?120 to 44°C by variable-temperature solid-state high-resolution 13C nuclear magnetic resonance (NMR) spectroscopy, in order to determine accurately the dynamics of the noncrystalline region of the polymer. From these results, it was found that the T1 minimum for the CH2 carbons in the noncrystalline region of solution-crystallized polyethylene with high crystallinity appears at higher temperature by about 20°C than that of melt-quenched polyethylene with low crystallinity. This means that the molecular motion of the CH2 carbons in the noncrystalline regions is more constrained at a given temperature in the material of higher crystallinity. Furthermore, dynamics of the noncrystalline region is discussed in terms of the 13C dipolar dephasing times. 相似文献