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711.
712.
We developed the new intermolecular interaction model of C(60) with the quantitative accuracy for the molecular orientational properties in crystals. The energy difference (DeltaE) and the activation barrier (E(barrier)) between the two stable orientations (P and H orientations) in crystals are in the values of +14.7 and +260 meV in our model, respectively; these values are in fairly good agreement with the experimental values (DeltaE approximately +11 meV, E(barrier)=+235-+290 meV in experiments). The relaxation calculation for C(60) crystals using our model revealed that there is the reversal of the stable orientations between the P and H orientations under the high H-orientation occupancy (p(H)) in crystals, when p(H)>0.83, DeltaE<0. From the molecular dynamics calculations for C(60) crystals using our model, it is found that the phase transition is induced at T(C)=200-260 K, which is consistent with the experimental value of 260 K. Immediately below T(C), we found a great variety of molecular rotational jumps involving that between the P and H orientations every about 10(-9) s due to the thermal activation. In the high temperature phase (>T(C)), all molecules rotate irregularly like in Brownian motion involving the rotational "slumber" for approximately 10(-12)-10(-11) s. 相似文献
713.
We consider the Cauchy problem for a semilinear heat equation with power nonlinearity. It is known that the equation has a singular steady state in some parameter range. Our concern is a solution with a moving singularity that is obtained by perturbing the singular steady state. By formal expansion, it turns out that the remainder term must satisfy a certain parabolic equation with inverse-square potential. From the well-posedness of this equation, we see that there appears a critical exponent. Paying attention to this exponent, for a prescribed motion of the singular point and suitable initial data, we establish the time-local existence, uniqueness and comparison principle for such singular solutions. We also consider solutions with multiple singularities. 相似文献
714.
Linda M. Benson Christopher J. Mason Oren Friedman Hirohito Kita Harold Robert Bergen III Douglas A. Plager 《Journal of separation science》2009,32(1):44-56
Allergic rhinitis (AR), chronic rhinosinusitis (CRS), and asthma are prevalent airway diseases that can have a substantial impact on a patient's quality of life. MS analyses of biological fluids can effectively screen for proteins associated with disease processes, however, initial detection of diagnostic proteins is difficult due to protein complexity and dynamic range. To enhance the detection of lower abundance proteins, intact nasal lavage fluid (NLF) proteins from nonpolypoid AR and from asthmatic CRS patients were extensively fractionated prior to LC/MS/MS analysis. Pooled NLF samples were processed to remove low molecular weight molecules and high abundance plasma proteins. Anion exchange (AX) chromatography followed by RP‐LC further separated the remaining intact NLF proteins. The resulting fractions were digested with trypsin and the peptides analyzed by LC/MS/MS. Spectra were searched with MASCOT, SEQUEST, and X!Tandem to obtain peptide identifications and subsequently analyzed by Scaffold software to identify parent proteins with at least 99% confidence. The 197 identified proteins are compared to those previously cited in the literature and the workflow evaluated to determine the usefulness for the detection of lower abundance proteins. This is the first extensive list of NLF proteins generated from CRS patients with coexisting asthma. 相似文献
715.
Mikio Kishimoto Makoto MinagawaHideto Yanagihara Tatsuya OdaNobuhiro Ohkochi Eiji Kita 《Journal of magnetism and magnetic materials》2012,324(7):1285-1289
Platelet γ-Fe2O3 particles of particle size less than 100 nm were prepared for medical applications that use the hysteresis-loss heating of ferromagnetic particles. The γ-Fe2O3 particles were obtained through the dehydration, reduction, and oxidation of platelet α-FeOOH particles, which were synthesized by the precipitation of ferric ions in an alkaline solution containing ethanolamine, and the crystals grown using a hydrothermal treatment. The γ-Fe2O3 particles contained dimples formed by the dehydration of α-FeOOH particles. The coercive force and the saturation magnetization of the γ-Fe2O3 particles were in the ranges 11.9 to 12.7 kA/m (150 to 160 Oe), and 70 to 72 Am2/kg (70 to 72 emu/g), respectively. The specific loss power of the γ-Fe2O3 particles, estimated from their temperature-raising property measured under a peak magnetic field of 50.9 kA/m (640 Oe) and at a frequency of 117 kHz, was 590 W/g. This value is higher than that of spherical cobalt-containing iron oxide particles having equivalent coercive force and saturation magnetization, reflecting the larger area of the minor hysteresis loop measured under a peak magnetic field of 50.9 kA/m (640 Oe). 相似文献
716.
A. Ichinose H. Kai M. Mukaida S. Horii R. Kita K. Matsumoto Y. Yoshida 《Journal of Crystal Growth》2010,312(20):2914-2918
Critical current density under magnetic fields has been improved by the introduction of artificial pinning centers. Nanorods in REBa2Cu3Oy films are significantly effective as c-axis-correlated pinning centers. However, nanorods sometimes tilt from the c-axis direction of superconducting films. To understand the mechanism of nanorod tilting, ErBa2Cu3Oy films containing Ba(Nb0.5Er0.5)O3 (BNO) nanorods were deposited on a SrTiO3 single crystal with a vicinal surface. Microstructures of the nanorods were examined by transmission electron microscopy (TEM). As a result, it was found that BNO nanorods grew diagonally from steps of the substrate surface in cross-sectional TEM images. The mechanism of the diagonal growth of nanorods can be explained by the segregation coefficient. 相似文献
717.
718.
Yusuke Hioki Dr. Tatsuya Sato Dr. Toyoki Iwao Junya Ikuma Dr. Atsushi Kawamura Dr. Takayuki Ohyoshi Dr. Yuta Tsunematsu Dr. Masaki Kita 《European journal of organic chemistry》2023,26(12):e202300084
The shell-less herbivorous marine mollusk (sea hare) Aplysia kurodai is known to contain a variety of bioactive substances. While these compounds have been thought to originate from sea algae or their associated microbes, most of their origin and acquisition pathways are still unclear. Six new cytotoxic aplaminone derivatives, bromodopamine-terpenoid hybrid molecules, were isolated from A. kurodai. Among them, isoaplaminone had a reverse prenyl group at the C15 aliphatic chain, which is a rare structural feature from the viewpoint of terpenoid biosynthesis. Investigation for chemical components in A. kurodai and the sea algae collected at several different locations revealed that two major aplaminones were contained in the Laurencia complex species at specific sites. Our chemical and ecological studies provide new insights into the origin of marine alkaloid toxins and their dynamism through the food chain. 相似文献
719.
720.