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1.
The computation of long wave propagation through the ocean obviously depends on the initial condition. When the waves are generated by a moving bottom, a traditional approach consists in translating the ‘frozen’ sea bed deformation to the free surface and propagating it. The present study shows the differences between the classical approach (passive generation) and the active generation where the bottom motion is included. The analytical solutions presented here exhibit some of the drawbacks of passive generation. The linearized solutions seem to be sufficient to consider the generation of water waves by a moving bottom. To cite this article: D. Dutykh et al., C. R. Acad. Sci. Paris, Ser. I 343 (2006). 相似文献
2.
FexNi100−x nanometric films were deposited on SiO2/Si substrates at room temperature using the pulsed laser deposition technique. The targets were Fe-Ni amorphous magnetic foils with composition Fe50Ni50, Fe35Ni65 and Fe22Ni78. Morphological and structural properties of the deposited films were investigated using scanning electron microscopy, Rutherford backscattering spectrometry, grazing incidence X-ray diffraction, and X-ray reflectivity. Electrical and magnetic characteristics of the films were investigated by using the four-point probe and the magneto-optic Kerr effect techniques, respectively. The film properties are strictly dependent on the Fe-Ni compositional ratio. 相似文献
3.
A. N. Vasiliev V. N. Grishin A. M. Davidenko A. A. Derevschikov Yu. A. Matulenko Yu. M. Melnik A. P. Meschanin V. V. Mochalov L. V. Nogach S. B. Nurushev A. F. Prudkoglyad P. A. Semenov L. F. Soloviev V. L. Solovianov V. Yu. Khodyrev K. E. Shestermanov A. E. Yakutin N. S. Borisov V. N. Matafonov A. B. Neganov Yu. A. Plis Yu. A. Usov A. N. Fedorov A. A. Lukhanin 《Physics of Atomic Nuclei》2004,67(8):1487-1494
Results are presented that were obtained by measuring single-spin asymmetry in the inclusive production of neutral pions in the reaction p+p ↑→ π 0+X at x F≈0. A beam of 70-GeV protons was extracted directly from the vacuum chamber of the accelerator by means of a bent single crystal. For transverse momenta in the range 1.0<p T<3.0 GeV/c, the single-spin asymmetry independently measured by two detectors is zero within the errors. This result is in agreement with Fermilab data obtained at 200 GeV, but it is at odds with CERN data measured at 24 GeV. 相似文献
4.
V. V. Barbakadze E. P. Kemertelidze I. Targamadze K. Mulkidzhanyan J. Kemink A. J. J. van den Berg K. J. Beukelman A. I. Usov 《Chemistry of Natural Compounds》2005,41(4):374-377
Two high-molecular-weight (>1000 kDa) water-soluble preparations were isolated from stems of Symphytum asperum and S. caucasicum. Their basic component was established as poly[hydroxy-1-carboxy-2-(3,4-dihydroxyphenyl)ethylene], analogous to that of high-molecular-weight
(>1000 kDa) preparations from roots of these same plants, using IR and NMR spectral data.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 303–305, July–August, 2005.
An erratum to this article is available at . 相似文献
5.
I. I. Kandror V. A. Usov I. O. Bragina T. L. Usova V. K. Bel'skii M. G. Voronkov 《Russian Chemical Bulletin》1989,38(4):811-815
1. | Radical arylation of 3-arylamino-2-phenyl-1-indenthiones with aryldiazonium fluoroborates or N-nitrosoacetanilide leads to the corresponding 1-arylamino-2-phenyl-3-arylthioindenes with high yield. Partial hydrolysis of the latter under the reaction conditions form 1-oxo-2-phenyl-3-arylthioindenes as by-products. |
2. | The similarity of thioamides and their vinylogs (the aminoindenthiones) in radical arylation reactions was established. |
6.
A theoretical and experimental treatment of axial dispersion in coiled tubes is presented. The dispersion, δ, is related to the theoretical plate height divided by four times the radius of the tube (H/4r). This parameter, when plotted against the product of the Reynolds number and the Schmidt number (ReSc), accurately predicts maxima in dispersion curves. Variations in the boundary layer thickness and the velocity profile cause the dispersion to pass through a maximum at a constant value of log (De2Sc1·14) equal to 6.13 for unretained solutes (De is the Dean number). A new measure of dispersion is proposed; the reduced dispersion, ? = 256/(Re0.667Sc), is derived from the experimental behavior of dispersion at values of log (De2Sc1·14) smaller than 6.13. The logarithm of ? is found to be approximately zero for 2.2 < log (De2Sc1·14) < 6.1 and to decrease linearly with log (De2Sc1·14) at higher values. Experiments with four solutes that have a wide range of molecular diffusivities are reported. Results agree with theory. 相似文献
7.
8.
R.V. Denys V.A. Yartys Masashi Sato R.G. Delaplane 《Journal of solid state chemistry》2007,180(9):2566-2576
A new intermetallic deuteride Ce2Ni7D4.7 with an anomalous volume expansion has been studied. Its structure was solved on the basis of in situ neutron diffraction data. Expansion proceeds along the c-axis and within the CeNi2 slabs only. All D atoms are located inside these slabs and on the border between CeNi2 and CeNi5. Ordering of D atoms in the bulk of CeNi2 is accompanied by substantial deformation of these slabs thus lowering the hexagonal symmetry to orthorhombic [space group Pmcn (No. 62); a=4.9251(3) Å, b=8.4933(4) Å, c=29.773(1) Å]. Inside the CeNi2 layer the hydrogen sublattice is completely ordered; all D-D distances exceed 2.0 Å. Local coordination of Ni by D inside the CeNi2 blocks is of “open”, saddle-like type. Hydrogen ordering is mainly determined by Ce-H and H-H interactions. The pressure-composition-temperature measurements yielded the following thermodynamic parameters of the formation of the hydride: ΔH=−22.4 kJ/molH, ΔS=−59.9 J/(K molH). 相似文献
9.
A. Thomas N. S. Borisov H. -J. Arends A. N. Fedorov G. M. Gurevich R. L. Kondratiev M. Korolija A. B. Lazarev M. Martinez W. Meyer S. V. Mironov A. B. Neganov V. N. Pavlov H. Ortega G. Reicherz Yu. A. Usov 《Physics of Particles and Nuclei》2013,44(6):964-967
The new frozen spin polarized target for experiments at the polarized beam of the real photon facility A2 of the MAMI accelerator is described. The A2-collaboration at the Mainz Microtron MAMI is measuring photon absorption cross section using circularly and linearly polarized photons up to the energy of 1.5 GeV. The photons are produced in the’ Bremsstrahlungs’ process. In the years 2005/2006 the Crystal Ball detector with its unique capability to cope with multi photon final states was set up in Mainz. Since 2010 the experimental apparatus has been completed by a polarized target. The horizontal dilution refrigerator of the Frozen-Spin Target has been constructed and is operated in close cooperation with the Joint Institute for Nuclear Research in Dubna, Russia. The system offers the opportunity to provide longitudinally and transversely polarized protons and deuteron. In this paper the operation experience of this new Frozen-Spin Target and first results from the runs in 2010 and 2011 are presented. 相似文献
10.
Konstantin Pliuta Alexander Chebotarev Anastasia Pliuta Denys Snigur 《Electroanalysis》2021,33(4):987-992
In current study the carbon-paste electrode modified by silica with embedded cetylpyridinium chloride for determination of Allura Red AC have been developed. The optimal conditions were determined to be for the square-wave voltammetric quantification: pH=2, Eads=300 mV, tads=300 s, amplitude – 40 mV, frequency – 25 Hz and potential scan rate is 250 mV sec−1. The calibration plot has linearity in the concentration ranges 0.04–0.2 μM and 0.2–1.00 μM. The LOD and LOQ are equal to 0.005 μM and 0.015 μM respectively. The crafted sensor has been applied successfully to model solutions and in jelly candies analysis with RSD no more than 10 %. 相似文献