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41.
We report the partial phonon densities of states (DOS) of iron sulfide, a possible component of the rocky planet's core, measured by the 57Fe nuclear resonant inelastic x-ray scattering and calculate the total phonon DOS under pressure. From the phonon DOS, we drive thermodynamic parameters. A comparison of the observed and estimated compressibilities makes it clear that there is a large pure electronic contribution in the observed compressibility in the metallic state. Our results present the observation of thermodynamic parameters of iron sulfide with the low-spin state of an Fe2+ ion at the high density, which is similar to the condition of the Martian core.  相似文献   
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The coefficient of normal restitution in an oblique impact is theoretically studied. Using a two-dimensional lattice model for an elastic disk and an elastic wall, we demonstrate that the coefficient of normal restitution can exceed unity and has a peak against the incident angle in our simulation. We also explain this behavior based upon a phenomenological theory.  相似文献   
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Peptides that bind to poly(phenylene vinylene) (PPV) were identified by the phage display method. Aromatic amino acids were enriched in these peptide sequences, suggesting that a π-π interaction is the key interaction between the peptides and PPV. The surface plasmon resonance (SPR) experiments using chemically synthesized peptides demonstrated that the Hyp01 peptide, with the sequence His-Thr-Asp-Trp-Arg-Leu-Gly-Thr-Trp-His-His-Ser, showed an affinity constant (7.7 × 10(5) M(-1)) for the target, hyperbranched PPV (hypPPV) film. This value is 15-fold greater than its affinity for linear PPV (linPPV). In contrast, the peptide screened for linPPV (Lin01) showed the reverse specificity for linPPV. These results suggested that the Hyp01 and Lin01 peptides selectively recognized the linear or branched structure of PPVs. The Ala-scanning experiment, circular dichroism (CD) spectrometry, and molecular modeling of the Hyp01 peptide indicated that adequate location of two Trp residues by forming the polyproline type II (P(II)) helical conformation allowed the peptide to specifically interact with hypPPV.  相似文献   
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Recently reported triple‐resonance Y‐relayed 1H,X correlation experiments have been utilized to characterize 183W and 57Fe chemical shifts using 119Sn as the Y‐relaying nucleus instead of the previously used 31P. Application of an adaptation of Gudat's original INEPT/HMQC sequence results in a significant enhancement of the signal‐to‐noise (S/N) ratio for two‐dimensional 119Sn‐relayed 1H,183W and 1H, 57Fe correlation spectra with efficient detection of the transition metal nucleus in tungsten and iron complexes lacking an observable direct scalar coupling between the transition metal and any hydrogen nuclei. Strengths and shortcomings of the novel sequence and the original sequences reported by Gudat are discussed in the context of 119Sn‐relayed proton detection of very low frequency transition metal nuclei. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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The X-ray crystal structure of the title complex, Co(Cl2bprpi) is described. In this complex the Co(II) center displays a distorted octahedral coordination geometry. The piperazine ring exhibits boat conformation, forming chelate rings and capping the Co atom. The N2-Col-N3 angle is 69.41(15) degrees, extremely smaller than 90 degrees. Because the small angle causes a large steric hindrance, the piperazine ring can be effective as an ion size-recognition site. The molecular structure is stabilized by intramolecular N-H...O hydrogen bonds and Cl...H contacts.  相似文献   
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The author summarize the recent analysis of a two-fluid model which describes fluidized beds of granular particles. It has been found that near the transition point from stable fluidized beds to unstable ones the two-fluid model is reduced to the KdV equation with small dissipation. The amplitude and the propagating velocity of a pulse of the reduced equation is obtained.Department of Physics, Tohoku University, Sendai 980, Japan. E-mail: hisao@cmpt01.phys.tohoku.ac.jp. Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 99, No. 2, pp. 309–314, May, 1994.  相似文献   
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