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1.
Stability Properties of Maps Between Hopf Spaces 总被引:1,自引:0,他引:1
2.
Hiroshi Maruyama Tadao Ishii Naruhiko Bamba Hironobu Maeda Akihisa Koizumi Yuzo Yoshikawa Hitoshi Yamazaki 《Physica C: Superconductivity and its Applications》1989,160(5-6):524-532
The temperature dependence of the extended X-ray absorption fine structure (EXAFS) is studied in the high Tc superconductors, YBa2Cu3O7−δ. The measurements were done at the Cu K-edge for samples of two orthorhombic phases (Tc≈90 K and ≈58 K, respectively) and a nonsuperconducting tetragonal phase. Interatomic distances and mean square relative displacements σ2 for Cu-O bonds are determined by the least squares refinement. The results indicate that values of σ2 increase near Tc for both the orthorhombic samples. It is concluded that this anomalous behavior related to Tc is caused by an anomalous vibration of oxygen atoms in the Ba-O layer. Changes in the Cu-O distances from 300 to 20 K are not found. 相似文献
3.
Lian-Chun Park Tatsuo Maruyama Noriho Kamiya Masahiro Goto Hiroyuki Kuma Naotaka Hamasaki 《Analytical sciences》2004,20(11):1609-1611
The emergence of drug-resistant hepatitis B virus (HBV) has been reported in patients with prolonged administration of lamivudine, which is a potent drug for the prevention of HBV infection. Lamivudine-resistant HBV has several types of mutations at the YMDD motif of its DNA polymerase. We successfully demonstrated that monitoring the hybridization behavior in nanostructured reverse micelles enables us to detect single nucleotide polymorphisms (SNPs). With the aid of reverse micelles, a model 40-mer oligonucleotide containing a single-base substitution was clearly distinguished from the normal, complementary oligonucleotide. In addition, we extended this technique to a high-throughput analysis. The results obtained with a 96-well micro-plate reader indicated the possibility of SNPs detection toward multiple samples of patients. 相似文献
4.
Cellulose derivative resin (CDR) suspensions containing resin particles of cellulose nitrate (CDR(CN)), cellulose acetate (CDR(CA)), or cellulose triacetate (CDR(CTA)) were prepared as the sorbent for resin suspension injection (RSI) electrothermal atomic absorption spectrometry (ETAAS), in which fine resin particles holding a desired trace element were directly injected into the graphite tube as the suspension. To compare the sorption ability, the distribution ratios of the Mo(VI)-phenylfluorone complex were measured between the aqueous phase and the sorbents, including the CDRs mentioned above and the finely divided anion exchange resin (AR). The results showed that the sorption ability decreases in the following order: CDR(CN) > or = AR > CDR(CA) > or = CDR(CTA). It was concluded that CDR(CN) was able to extract more than 98% of Mo(VI), and was suitable for RSI-ETAAS as well as AR. CDR(CN) was used for the determination of Mo in NIES certified reference materials, No. 10 Rice flour-unpolished; the results showed fairly good agreements between the analytical values and the certified values. 相似文献
5.
The Constraint Molecular Dynamics approach is illustrated together with calculation on different heavy ion collisions. In particular the charge-mass distribution produced in the collision 124Sn + 64Ni and 112Sn + 58Ni at 35 MeV/nucleon is discussed. By comparing the Y = (N ? Z)/A distributions for fragments produced in central collisions it results that this observable can be sensitive to the dynamic effects induced on the two systems by the different charge/mass ratio. 相似文献
6.
Hirohisa Yokota Kenji Kamoto Jun-ichi Igarashi Norihiko Mouri Yutaka Sasaki 《Optical Review》2002,9(1):9-12
A new configuration for an ASE reduction filter in EDFA repeaters for WDM optical transmission systems using optical fiber grating couplers (FGCs) was proposed and first demonstrated. The filtering characteristics of the proposed filter for amplified single wavelength signal and 2-channel WDM signals using EDFA were identified. It was found that the filter was effective to improve SNR in optical domain by reducing ASE noise. The required FGC characteristics for the filter were theoretically predicted under the condition that the total filter loss did not exceed 3 dB. More than 70% of drop efficiency was required in each FGC for the application of the proposed filter to an 8-channel WDM system using EDFA repeaters. 相似文献
7.
Deependra Das Mulmi Nozomi Kamiya Yutaka Murakami 《Journal of Physics and Chemistry of Solids》2004,65(6):1181-1185
Nb-doped anatase TiO2 single crystal has been grown by chemical vapour transport method. Raman spectra shows that the obtained crystal with Nb of 0.08 wt% has typical anatase structure. An absorption band was observed at around 2.2 eV, which seems to be due to the d-d transition in the conduction band. The electron paramagnetic resonance and electric resistivity measurements show that the doped niobium makes quite shallow donor level whose orbital is dxy-like centered at the titanium position of anatase. 相似文献
8.
9.
The convenient method for the synthesis of 1,3-oxathiolan-2-ones by the reaction of epoxides with elemental sulfur and carbon monoxide in the presence of catalytic amount of sodium hydride has been developed. 相似文献
10.
Yuzo Maruyama 《Journal of multivariate analysis》2004,88(2):320-334
We consider estimation of a multivariate normal mean vector under sum of squared error loss.We propose a new class of minimax admissible estimator which are generalized Bayes with respect to a prior distribution which is a mixture of a point prior at the origin and a continuous hierarchical type prior. We also study conditions under which these generalized Bayes minimax estimators improve on the James–Stein estimator and on the positive-part James–Stein estimator. 相似文献