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101.
Kotaro Ishiji Tomoyuki Matsuda Hiroko Tokoro Toshiaki Iwazumi Shin-ichi Ohkoshi 《Journal of Physics and Chemistry of Solids》2007,68(11):2158-2161
Cesium manganese hexacyanoferrates exhibit an interesting phenomenon of temperature-induced phase transition accompanied by a variation in the magnetic susceptibility. We observed the variation in the electronic state of Mn during the phase transition by using X-ray absorption spectroscopy. The results of the analyses showed that the content ratio of FeII-CN-MnIII and FeIII-CN-MnII systematically varied during the phase transition. However, the ratio of FeII-CN-MnII remained constant at almost all temperatures. These results suggest that the charge transfer between Fe and Mn ions in the FeIII-CN-MnII or the FeII-CN-MnIII bond produces the phase transition. 相似文献
102.
Yuji Sano Kotaro Shirai Naoto Takahata Takafumi Hirata Neil C Sturchio 《Analytical sciences》2005,21(9):1091-1097
Concentrations of minor (Mg and Sr) and trace (Ba and U) elements in four natural calcium carbonate samples were first analyzed by inductively coupled plasma mass spectrometry (ICP-MS) after chemical dissolution and calibrated against a standard dolomite. Their homogeneities were checked by in situ laser ablation (LA) ICP-MS with 10-20 spots. The carbonate samples were measured by using a high lateral resolution secondary ion mass spectrometer (Nano-SIMS NS50). A approximately 4 nA O- primary beam was used to sputter a 5-6-microm diameter crater on the sample surface, and secondary positive ions were extracted for mass analysis using an accelerating voltage of 8 kV and a Mattauch-Herzog geometry. A multi-collector system was adjusted to detect 26Mg+, 43Ca+, 88Sr+, 138Ba+, 238U16O+ and 238U16O2+ ions at the same time. A resolving power of 2500-5000 at 10% peak height was attained by an entrance slit set at 40 microm, and each exit slit at 50 microm with adequate flat-topped peaks. The observed 26Mg/43Ca, 88Sr/43Ca, 138Ba/43Ca and 238U16O2/43Ca ratios agreed well with those measured by LA-ICP-MS. Foraminifera shells were analyzed at 5-6 microm scale by Nano-SIMS. There was a large variation of the Mg/Ca ratios, up to +/- 38%, even in a single fragment of the shell, suggesting that although the ratios provide a useful paleoceanographic proxy at bulk scale, they may reflect a more complex pattern at < 10 microm scale. 相似文献
103.
An accurate solution for the three-nucleon bound state is obtained within 1 keV in the binding energy and, on the whole,
better than 1% in the wave function, using a new systematic and efficient method. The method is based on a recently developed
separable expansion for any finite-range interaction, in which a rigorous separable series for the two-body t-matrix is obtained by expanding the wave function in terms of a complete set of basis functions inside the range of the potential.
In order to treat a potential with a strong repulsive core, as in the case of the Argonne potential, we develop a two-potential
formalism. The expansion starts with a few EST (Ernst, Shakin, and Thaler) terms in order to accelerate the convergence and
continues with an orthogonal set of polynomials, avoiding the known difficulties of a pure EST expansion. Thus, several techniques
are combined in the present extended separable expansion (ESE). In this way, the method opens a new systematic treatment for
accurate few-body calculations resulting in a dramatic reduction in the CPU time required to solve few-body equations.
Received November 6, 1996; revised April 14, 1997; accepted for publication April 30, 1997 相似文献
104.
105.
106.
K. Tanaka K. Yoshizawa T. Koike T. Yamabe J. Yamauchi Y. Deguchi S. Yata 《Solid State Communications》1984,52(3):343-345
ESR measurements have been performed on the polyacenic material prepared by the pyrolytic treatment of phenol-formaldehyde resin. Six kinds of samples (A)-(F) with various electrical conductivity (σ) were employed for the measurements. Each sample shows a single narrow line, the g-values of which suggest the existence of unpaired electrons of π-type. If the sample (F) (σ = 1 × 10° S cm?1) the single narrow line becomes drastically diminished in the presence of a small amount of oxygen. 相似文献
107.
The 13C NMR spectra of β-carboline alkaloids were determined, and unambiguous assignments of the spectra were carried out from the long-range coupling constants. 相似文献
108.
109.
Morita K Sankaran NB Huang W Seino T Sato Y Nishizawa S Teramae N 《Chemical communications (Cambridge, England)》2006,(22):2376-2378
An abasic site-containing DNA combined with lumiflavin allows amperometric determination of single nucleotide polymorphism through hydrogen bond-mediated nucleobase recognition in water by using abasic sites as a molecular recognition field. 相似文献
110.
During the past decade, the Ratip program has been found useful for calculating a variety of atomic properties, including energies, transition probabilities, Auger parameters as well as a number of excitation, ionization and capture cross sections for processes with a single electron in the continuum. Recently, in addition, this suite of programs was extended to predict also the isotope shift and hyperfine parameters of open-shell atoms and ions. Here, we review the latest developments of the Ratip program with emphasis on the specific mass-shift M sms and field-shift F parameters. Detailed computations for these parameters have been carried out especially for the $4s\;^2S_{1/2} - 4p\;^2P_{1/2,3/2}$ transitions at ~ 397 nm of singly-charged Ca?+? ions and are compared with available data from the literature. 相似文献