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151.
O. Adriani L. Bonechi M. Bongi R. D’Alessandro P. Papini D. A. Faus J. Velasco M. Haguenauer Y. Itow K. Masuda Y. Matsubara H. Matsumoto H. Menjo Y. Muraki T. Sako K. Kasahara T. Tamura K. Yoshida 《Czechoslovak Journal of Physics》2006,56(1):A107-A116
The LHCf experiment will be installed in 2007 on the LHC collider in the forward direction at ±140m from the ATLAS interaction point. The purpose of LHCf is to precisely measure the pion production cross section near zero degrees through the measurement of the photons produced in neutral pion decay. This measurement is crucial for the simulation of the showers induced in the atmosphere by very high energy cosmic rays; the 14 TeV energy available in the center of mass frame corresponds in fact to an equivalent energy of 1017 eV in the laboratory system. The paper focus on the proposed experiment and on the physics results that we expect from it. 相似文献
152.
K. Kasahara 《Optical and Quantum Electronics》1992,24(8):783-800
Recent progress is reviewed in surface-normal optoelectronic devices primarily for use in optical switching and information processing. A type of optoelectronic integrated circuit (OEIC), the surface-normal two-dimensional array, is fabricated using these devices. This improves on first-generation OEICs by featuring large-scale integration in a small area, which results in a higher production yield. It also has structures which can easily be integrated with electronic circuits and can meet multichannel requirements. This approach supports optoelectronic progress towards optical information processing. 相似文献
153.
Triplet state sublevel spectroscopy using optical detection of magnetic resonance (ODMR) in zero magnetic field can be successfully
employed to study (i) the environment of tryptophan (Trp) residues in a protein by observing the position and structure of
phosphorescence spectra, zero field ODMR transitions and triplet state sublevel kinetics, (ii) the energy transfer among Trp
residues, and (iii) whether any cysteine (Cys) residue is within van der Waals distance of any Trp residue by studying the
complex of the protein with methylmercury(II) iodide (CH3HgI) which binds to Cys residues. These studies are particularly important where crystal structure study is not possible.
Study of the S1 state often gives ambiguous results since fluorescence is always broad and shows multi-exponential decay. Our results on
bacteriophage lysozyme T4 which contains three Trp residues at positions 126, 138 and 158 are presented. Measurements were
facilitated by the use of a mutated enzyme containing one or two Trp-Tyr substitutions. The results indicate that (i) Trp
126 and 158 are solvent exposed, whereas Trp 138 is buried in a hydrophobic environment, (ii)S ↔S non-radiative energy transfer takes place predominantly from Trp 126 to Trp 158, and (iii) only Trp-158 undergoes a heavy
atom perturbation, which affects selectively the z-sublevel (z is an out-of-plane axis of the indole plane) as a result of
CH3HgI binding to nearby Cys 97. We suggest that the Hg atom is located on the z-axis of Trp 158 in the complex. This interpretation
is based on our investigations on the effect of orientation of heavy atom perturbers in some naphthalene-crown ether metal
ion complexes. 相似文献
154.
155.
156.
Sanjib Ghosh Jeffry G. Weers Michael Petrin August H. Maki 《Chemical physics letters》1984,108(1):87-93
The temperature dependence of the individual spin—lattice relaxation rate constants (Wij) between the lowest triplet sublevels of naphthalene-h8 in a polycrystalline Shpol'skii matrix of n-pentane have been measured between 1.2 and 2.4 K in zero field. The total sublevel decay constants are evaluated and found to be independent of temperature. The Wij are found to be highly anisotropic, but the anisotropy pattern differs from that observed previously in a durene matrix. 相似文献
157.
The surface electronic structure of the binary metal oxide ZrO2/SiO2 was studied by means of XPS and the decrete variational (DV) Xα cluster model calculation. The results show that when ZrO2, was supported on SiO2, the SiO bond of SiO2, neighboring ZrO4, became stronger and that the Brönsted acid site H which is located on the SiO4 unit exhibits stronger acidity. 相似文献
158.
A. Maki S. Mikamo M. Ono M. Takasaki A. Yamamoto H. Hirabayashi S. Kurokawa A. Kusumegi S. Higashi F. Kajino Y. Kawashima M. Nakashita S. Ozaki T. Takahashi Y. Teramoto S. Yamamoto S. Naito Y. Sakai M. Mishina 《Physics letters. [Part B]》1981,106(5):423-427
Direct production of single electrons in proton-nucleus collisions at 13 GeV/c has been measured. A rising ratio with decreasing pT above the 10?4 level is observed for low pT single electrons. The source of the rising ratio at low ratio at low pT is discussed in connection with the low mass dielectron continuum below the ? mass region. 相似文献
159.
160.
A Kasahara T Onodera M Mogi Y Oshima M Shimizu 《Chemical & pharmaceutical bulletin》1965,13(12):1460-1469