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111.
Bogdan Constantinescu Angela Vasilescu Martin Radtke Uwe Reinholz Claire Pacheco Laurent Pichon Ernest Oberländer-Târnoveanu 《Applied Physics A: Materials Science & Processing》2012,109(2):395-402
A thorough microscopic investigation by SR XRF and micro-PIXE brings insight into the probable techniques used in the manufacture of thirteen Dacian gold bracelets, one of the most spectacular archaeological finds ever on the territory of Romania. 相似文献
112.
113.
Carlos F. Pedroso Julcemara G. de Oliveira Francinete R. Campos Alan G. Gon?alves Angela C. L. B. Trindade Roberto Pontarolo 《Chromatographia》2009,69(Z2):201-206
A simple RP–LC method for simultaneous quantification of losartan and amlodipine and separation of their degradation products
has been developed. For this purpose we tested appropriated mobile phase pH range, flow rate, temperature and different columns.
The method was validated with an ODS column. A gradient of acetonitrile and phosphate pH 3.0 buffer was utilized as mobile
phase. The linearity was determined at 50–150% level. Individual recoveries at 70–130% level ranged from 98.8 to 100.5% for
losartan and 96.4–101.2% for amlodipine. The robustness was also evaluated. Although losartan has much higher quantities than
amlodipine in commercial tablets, this method allowed simultaneous quantification for both drugs. 相似文献
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116.
Daniel Castaño Díez Max Gunzburger Angela Kunoth 《Numerical Methods for Partial Differential Equations》2008,24(6):1388-1404
We extend the multiscale finite element viscosity method for hyperbolic conservation laws developed in terms of hierarchical finite element bases to a (pre‐orthogonal spline‐)wavelet basis. Depending on an appropriate error criterion, the multiscale framework allows for a controlled adaptive resolution of discontinuities of the solution. The nonlinearity in the weak form is treated by solving a least‐squares data fitting problem. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2008 相似文献
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118.
Bartolo Gabriele Raffaella Mancuso Giuseppe Ruffolo Angela Dibenedetto 《Tetrahedron letters》2009,50(52):7330-1772
In the presence of a PdI2-based catalytic system, 1,2-diols undergo an oxidative carbonylation process to afford 5-membered cyclic carbonates in good to excellent yields (84-94%) and with unprecedented catalytic efficiencies for this kind of reaction (up to ca. 190 mol of product per mol of PdI2). Under similar conditions, 6-membered cyclic carbonates are obtained for the first time through a direct catalytic oxidative carbonylation of 1,3-diols (66-74% yields). 相似文献
119.
We construct positive and sign changing multipeak solutions to the pure critical exponent problem in a bounded domain with a shrinking hole, having a peak which concentrates at some point inside the shrinking hole (i.e. outside the domain) and one or more peaks which concentrate at interior points of the domain. These are, to our knowledge, the first multipeak solutions in a domain with a single small hole. 相似文献
120.
Garth A. Jones Angela Acocella Francesco Zerbetto 《Theoretical chemistry accounts》2007,118(1):99-106
An explicit electron dynamics approach has been used to calculate the nonlinear optical properties of C60 and its radical anion. An external perturbation, in the form of an oscillating electric field, induces the time-evolution
of the molecular wavefunction. The time-averaged instantaneous dipole moment of the systems gives the molecular response to
perturbations of varying field intensities and frequency of oscillation. The polarizabilities and the second-order hyperpolarizabilties
have been calculated and are in good qualitative agreement with experimentally available data. In line with previous theoretical
and experimental studies, the nonlinear effect is enhanced for the radical species.
Contribution to the Fernando Bernardi Memorial Issue. 相似文献