684 research outputs found
TANDEM MASS SPECTROMETER WITH OCTOPOLE ION TRAP FOR PHOTODISSOCIATION SPECTROSCOPY OF CLUSTER IONS
Space-Time Structure of Loop Quantum Black Hole
In this paper we have improved the semiclassical analysis of loop quantum
black hole (LQBH) in the conservative approach of constant polymeric parameter.
In particular we have focused our attention on the space-time structure. We
have introduced a very simple modification of the spherically symmetric
Hamiltonian constraint in its holonomic version. The new quantum constraint
reduces to the classical constraint when the polymeric parameter goes to
zero.Using this modification we have obtained a large class of semiclassical
solutions parametrized by a generic function of the polymeric parameter. We
have found that only a particular choice of this function reproduces the black
hole solution with the correct asymptotic flat limit. In r=0 the semiclassical
metric is regular and the Kretschmann invariant has a maximum peaked in
L-Planck. The radial position of the pick does not depend on the black hole
mass and the polymeric parameter. The semiclassical solution is very similar to
the Reissner-Nordstrom metric. We have constructed the Carter-Penrose diagrams
explicitly, giving a causal description of the space-time and its maximal
extension. The LQBH metric interpolates between two asymptotically flat
regions, the r to infinity region and the r to 0 region. We have studied the
thermodynamics of the semiclassical solution. The temperature, entropy and the
evaporation process are regular and could be defined independently from the
polymeric parameter. We have studied the particular metric when the polymeric
parameter goes towards to zero. This metric is regular in r=0 and has only one
event horizon in r = 2m. The Kretschmann invariant maximum depends only on
L-Planck. The polymeric parameter does not play any role in the black hole
singularity resolution. The thermodynamics is the same.Comment: 17 pages, 19 figure
Cu- and Cl-NMR Studies of Triplet Localization in the Quantum Spin System NHCuCl
Cu- and Cl-NMR experiments were performed to investigate
triplet localization in the dimer compound NHCuCl, which shows
magnetization plateaus at one-quarter and three-quarters of the saturation
magnetization. In Cu-NMR experiments, signal from only the singlet Cu
site was observed, because that from the triplet Cu site was invisible due to
the strong spin fluctuation of onsite 3-spins. We found that the temperature
dependence of the shift of Cu-NMR spectra at the singlet Cu site
deviated from that of macroscopic magnetization below T=6 K. This deviation is
interpreted as the triplet localization in this system. From the
Cl-NMR experiments at the 1/4-plateau phase, we found the two
different temperature dependences of Cl-shift, namely the temperature
dependence of one deviates below T=6 K from that of the macroscopic
magnetization as observed in the Cu-NMR experiments, whereas the
other corresponds well with that of the macroscopic magnetization in the entire
experimental temperature region. We interpreted these dependences as reflecting
the transferred hyperfine field at the Cl site located at a singlet site and at
a triplet site, respectively. This result also indicates that the triplets are
localized at low temperatures. Cu-NMR experiments performed at high
magnetic fields between the one-quarter and three-quarters magnetization
plateaus have revealed that the two differently oriented dimers in the unit
cell are equally occupied by triplets, the fact of which limits the theoretical
model on the periodic structure of the localized triplets.Comment: 19 pages, 9 figures, submitted to PRB (in press
Charge Resonance and Charge Transfer Interactions in Naphthalene Homo- and Hetero-Dimers
Charge resonance interaction in naphthalene homo- and hetero-dimer cations is studied by photodissociation spectroscopy of the charge resonance and the local excitation transitions. The resonance interaction in naphthalene dimer cation is slightly weaker than that of a benzene dimer cation because of partial overlapping of the respective aromatic rings. A local excitation band of the benzene cation chromophore is observed in the spectrum of a naphthalene-benzene hetero-dimer cation at nearly the same position as that of the benzene dimer cation. This indicates that in spite of its higher ionization potential the positive charge stays on the benzene molecule in some probability. On the basis of the band position of the charge resonance transition as well as the intensity of the local excitation band, the probability is analyzed to be approximately 9 %. This means 91 % is localized on the naphthalene chromophore in this hetero-dimer.AIP Conference Proceedings 38
Ethyl 4-(4-bromophenyl)-6-r-phenyl-2-oxocyclohex-3-ene-1-t-carboxylate
In the title compound, C21H19BrO3, the cyclohexene ring adopts an envelope conformation, with all substituents equatorial. The plane through its five coplanar atoms makes dihedral angles of 28.88 (10) and 71.94 (10)° with the bromobenzene and phenyl rings, respectively. The dihedral angle between the latter two rings is 51.49 (15)°. Intermolecular C—H⋯O hydrogen bonds are found in the crystal structure; a C—H⋯π interaction is also present
Mother-to-embryo vitellogenin transport in a viviparous teleost Xenotoca eiseni
魚類がお腹の子供に与える栄養素を解明 --哺乳類が失った遺伝子を利用して胎生機構を獲得--. 京都大学プレスリリース. 2019-10-09.Vitellogenin (Vtg), a yolk nutrient protein that is synthesized in the livers of female animals, and subsequently carried into the ovary, contributes to vitellogenesis in oviparous animals. Thus, Vtg levels are elevated during oogenesis. In contrast, Vtg proteins have been genetically lost in viviparous mammals, thus the yolk protein is not involved in their oogenesis and embryonic development. In this study, we identified Vtg protein in the livers of females during the gestation of the viviparous teleost, Xenotoca eiseni. Although vitellogenesis is arrested during gestation, biochemical assays revealed that Vtg protein was present in ovarian tissues and lumen fluid. The Vtg protein was also detected in the trophotaeniae of the intraovarian embryo. Immunoelectron microscopy revealed that Vtg protein is absorbed into intracellular vesicles in the epithelial cells of the trophotaeniae. Furthermore, extraneous Vtg protein injected into the abdominal cavity of a pregnant female was subsequently detected in the trophotaeniae of the intraovarian embryo. Our data suggest that the yolk protein is one of the matrotrophic factors supplied from the mother to the intraovarian embryo during gestation in X. eiseni
Studies on Solvation Structure and Intracluster Reaction of Aqueous Metal Ions by IR Photodissociation Spectroscopy
セミナー開催, 2005年7月22日, Buntine Group, at The University of Adelaide, in Adelaide, Australi
Improvement of Write Efficiency in Voltage-Controlled Spintronic Memory by development of a Ta-B Spin Hall Electrode
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