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The ability of the JONSWAP model to describe swell spectra is analysed and the quality of the fit of this model is compared with the fits produced by a Gaussian model. The study is based on directional wave spectra from measuremen...
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The ability of the JONSWAP model to describe swell spectra is analysed and the quality of the fit of this model is compared with the fits produced by a Gaussian model. The study is based on directional wave spectra from measurements made at the Maui location situated in the west coast of New Zealand and at the Bonga location situated near the coast of Africa. The analysis is performed for single peak swell sea states and for the swell component of two peaked spectra.
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Arginine molecule has been analyzed in parallel by infrared (IR) and Raman spectroscopy at room temperature. Thevibrational spectra in the region 4000-400 cm~(-1) have been interpreted and band positions have been assigned tentati...
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Arginine molecule has been analyzed in parallel by infrared (IR) and Raman spectroscopy at room temperature. Thevibrational spectra in the region 4000-400 cm~(-1) have been interpreted and band positions have been assigned tentatively,subsequently, a complete and complementry set of vibrational data has been obtained that can be used to determine severalpossible vibrational sets. In addition, electronic absorption spectrum of this molecule has been monitored at several pHvalue which reveals the effect of change of pH on peak shift.
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Spectra of He-, Ne- and Ar-C_6D_6 in the region of the v12 fundamental of C_6D_6 are observed in a pulsed supersonic jet expansion using a tunable optical parametric oscillator laser source. These are the first reported infrared s...
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Spectra of He-, Ne- and Ar-C_6D_6 in the region of the v12 fundamental of C_6D_6 are observed in a pulsed supersonic jet expansion using a tunable optical parametric oscillator laser source. These are the first reported infrared spectra of rare gas-benzene complexes and the first observation in any region for He-and Ne-C_6D_6. Two bands are studied for each complex: the v_(12) fundamental itself (≈2289 cm~(-1)) and the ν_2 + ν_(13) combination band (≈2276 cm~(-1)) which are coupled by a Fermi resonance. Effective intermolecular separations of 3.593(1) and 3.455(1) ? are obtained for He- and Ne-C_6D_6, respectively, consistent with previous ultraviolet and microwave results for the analogous C_6H_6 complexes.
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The complex compound Eu(NO_3)_3·Bpy_3 (Bpy, 2,2'-bipyridine) was synthesised and analysed by methods of optical spectroscopy. The spectra and details of the structure were discussed and compared with ones of well-known compounds ...
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The complex compound Eu(NO_3)_3·Bpy_3 (Bpy, 2,2'-bipyridine) was synthesised and analysed by methods of optical spectroscopy. The spectra and details of the structure were discussed and compared with ones of well-known compounds Eu(NO_3)_3·Bpy_2 and Eu(NO_3)_3 -Phen_2 (Phen, 1,10-phenanthroline). The water admixed to the ethanol as solvent promotes Bpy building into the outer sphere of complex [Eu(NO_3)_3·Bpy_2] -Spy. Both kinds of Bpy molecules in Eu(NO_3)_3·Bpy_3 compound are nearer to coplanar, than Bpy in Eu(NO_3)_3·Bpy_2. The bonds Eu-N are stronger and the bonds Eu-O are weaker in Eu(NO_3)_3·Bpy_3 in comparison with the ones in Eu(NO_3)_3·Bpy_2. The outer-sphere Bpy molecule, effecting as a "steric" factor, changes the nearest surroundings of Eu3+ ion in [Eu(NO_3)_3·Bpy_2]-Bpy, making it similar to one of Eu(NO_3)_3-Phen_2.
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We identify the topological Hochschild homology (THH) of the Thom spectrum associated to an E_∞ classifying map X BG for G an appropriate group or monoid (e.g. U, O, and F). We deduce the comparison from the observation of McClur...
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We identify the topological Hochschild homology (THH) of the Thom spectrum associated to an E_∞ classifying map X BG for G an appropriate group or monoid (e.g. U, O, and F). We deduce the comparison from the observation of McClure, Schwanzl, and Vogt that THH of a cofibrant commutative S-algebra (E_∞-ring spectrum) R can be described as an indexed colimit together with a verification that the Lewis-May operadic Thom spectrum functor preserves indexed colimits and is in fact a left adjoint. We prove a splitting result THH(M?) ≌ M? ^ BX_+, which yields a convenient description of THH(MU). This splitting holds even when the classifying map ?:X → BG is only a homotopy commutative A_∞ map, provided that the induced multiplication on Mf extends to an E_∞-ring structure; this permits us to recover Bokstedt's calculation of THH(HZ).
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Undoped LaAlO3 and Ce-doped LaAlO3 single crystals were grown by the Czochralski process. The segregation coefficient of cerium ions in 1 at% Ce: LaAlO3 is 0.28. The undoped LaAlO3 and Ce-doped LaAlO3 single crystals were characte...
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Undoped LaAlO3 and Ce-doped LaAlO3 single crystals were grown by the Czochralski process. The segregation coefficient of cerium ions in 1 at% Ce: LaAlO3 is 0.28. The undoped LaAlO3 and Ce-doped LaAlO3 single crystals were characterized by infrared transmission spectra and ultraviolet/visible/near-IR absorption spectra. It was observed that the band-to-band absorption of LaAlO3 host is around 209 nm. Four characteristic f-f transitions of Ce3+ ion at 1923, 2354, 2669, and 3728 cm(-1) and five f-d transitions around 198, 206, 214, 246, and 316 nm in the Ce-doped LaAlO3 crystal were observed. Strong emission around 410 nm was also observed at excitation of 317 nm in the Ce-doped LaAlO3 single crystal. (C) 2004 Elsevier B.V. All rights reserved.
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Four clusters of ZnO, O-Zn-SR (-SR = ligand) and doping ZnO structures (with Cr, Cu, Al atoms) were investigated using density functional theory at theB3LYP/Lanl2dz level. The characteristics of Zn_3O_3 and Zn_4O_4 structures, whi...
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Four clusters of ZnO, O-Zn-SR (-SR = ligand) and doping ZnO structures (with Cr, Cu, Al atoms) were investigated using density functional theory at theB3LYP/Lanl2dz level. The characteristics of Zn_3O_3 and Zn_4O_4 structures, which are the units of experimental wurtzite and zinc blende structures, were found to be similar to those of experimental ZnO nanocrystals. Moreover, the calculated Raman and IR spectra of ZnO clusters were almost consistent with experimental results. Raman spectra were observed to shift to higher frequencies with decreasing numbers of atoms. Both ligands and solvent make the wavelength of absorption peaks shift to blue. All transitions of absorption peaks for these pure clusters were from d to p orbitals. Finally, doping clusters and experimental doping nanocrystals were similar in character. The doping of metal changed the orbital of ZnO nanocrystals. The transitions in doping clusters (Cr-ZnO, Cu-ZnO) are from d to d orbitals, while Al-ZnO clusters have s-p transitions.
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2,4,6-trimethylpyridinium 2,6-dichloro-4-nitrophenolate crystallizes in monoclinic system, space group P2_1/c, a = 7.534(2), b = 26.673(5), c = 8.452(2) A, β = 116.16(3)°, Z = 4. The planar molecules are arranged in the lattice ...
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2,4,6-trimethylpyridinium 2,6-dichloro-4-nitrophenolate crystallizes in monoclinic system, space group P2_1/c, a = 7.534(2), b = 26.673(5), c = 8.452(2) A, β = 116.16(3)°, Z = 4. The planar molecules are arranged in the lattice as antiparallel oriented pairs with the symmetry centre. The O~- …H-N~+ hydrogen bonds are relatively long, 2.686(4) A. The C-O bond length, 1.250(4) A, indicates an extended charge separation. The IR and UV-VIS spectra in KBr pellets confirm the ion pairs to be present in the solid state.
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The problem of sea wave climate description through climatic directional spectra is addressed and an example application is made to Portuguese coastal waters and Northeast Atlantic locations. The 44-year HIPOCAS hindcast data set ...
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The problem of sea wave climate description through climatic directional spectra is addressed and an example application is made to Portuguese coastal waters and Northeast Atlantic locations. The 44-year HIPOCAS hindcast data set is used for spectral parameterization, and statistical calculations are made for five locations: Figueira da Foz, Sines, Azores, Madeira (Canical) and Canaries. The occurrences of the spectral classes are estimated, and for each class the variability of the spectral parameters is described in terms of joint distributions. Different approaches for its parametric estimation are considered. These statistics are used for calculation of synthetic directional wave spectra (including extreme sea states) for different wave-making conditions.
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Laser-induced breakdown spectrum has been recorded in the region of 380-455 nm using second harmonics of Nd:YAG laser, computer-controlled TRIAX 320 M monochromator with a reciprocal linear dispersion 2.64 nm/mm fitted with ICCD d...
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Laser-induced breakdown spectrum has been recorded in the region of 380-455 nm using second harmonics of Nd:YAG laser, computer-controlled TRIAX 320 M monochromator with a reciprocal linear dispersion 2.64 nm/mm fitted with ICCD detector. The spectrum consists of 108 bands, which are classified into four new subsystems E0_u~+ (~1Σ_u~+) → A1_g(~3Π_g), J0_g~±\1_g(~3Σ_g~+) → D1_u(~1Π_u), F1_u → A0_g~±(~3Π_g) and F1_u → A2_g(~3Π_g) along with additional bands of the known system E0_u~+(~1Σ_u~+) → A0_g~±(~3Π_g). The molecular constants for these systems have also been determined.
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