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991.
Diego Montaño Isabel Bandrés Luz M. Ballesteros Carlos Lafuente Félix M. Royo 《Journal of solution chemistry》2011,40(7):1173-1186
In the present work we report experimental surface tensions for binary mixtures of isomeric chlorobutanes with methyl tert-butyl
ether from 283.15 to 303.15 K, measured with a drop volume tensiometer. From these experimental data the corresponding surface
tension deviations were calculated and correlated using a Redlich-Kister type polynomial. Finally, we include the calculation
of excess surface compositions for all of the mixtures from 288.15 K to 308.15 K. 相似文献
992.
Structural Chemistry - The adsorption of molecules on metal surfaces within confined spaces is key to industrially relevant processes such as catalytic conversions, separations, or gas storage.... 相似文献
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Claudio Cacciapuoti Domenico Finco Diego Noja Alessandro Teta 《Letters in Mathematical Physics》2014,104(12):1557-1570
In the present paper, we study the following scaled nonlinear Schrödinger equation (NLS) in one space dimension: $$ i\frac{\rm d}{{\rm d}t}\psi^{\varepsilon}(t)=-\Delta\psi^{\varepsilon}(t) +\frac{1}{\varepsilon}V\left(\frac{x}{\varepsilon} \right)|\psi^{\varepsilon}(t)|^{2\mu}\psi^{\varepsilon}(t)\quad \varepsilon > 0\,\quad V\in L^1(\mathbb{R},(1+|x|){\rm d}x) \cap L^\infty(\mathbb{R}).$$ This equation represents a nonlinear Schrödinger equation with a spatially concentrated nonlinearity. We show that in the limit \({\varepsilon\to 0}\) the weak (integral) dynamics converges in \({H^1(\mathbb{R})}\) to the weak dynamics of the NLS with point-concentrated nonlinearity: $$ i\frac{{\rm d}}{{\rm d}t} \psi(t) =H_{\alpha} \psi(t) .$$ where H α is the Laplacian with the nonlinear boundary condition at the origin \({\psi'(t,0+)-\psi'(t,0-)=\alpha|\psi(t,0)|^{2\mu}\psi(t,0)}\) and \({\alpha=\int_{\mathbb{R}}V{\rm d}x}\) . The convergence occurs for every \({\mu\in \mathbb{R}^+}\) if V ≥ 0 and for every \({\mu\in (0,1)}\) otherwise. The same result holds true for a nonlinearity with an arbitrary number N of concentration points. 相似文献
999.
Norma N. Buceta Diego Ruiz Gustavo P. Romanelli Juan C. Autino Helmut Duddeck Reinaldo Pis Diez Jorge L. Jios 《Journal of Physical Organic Chemistry》2014,27(2):106-113
The experimental 1H and 13C NMR spectra of 13 phenyl cinnamates and four 4‐methylcoumarins were investigated and their chemical shifts assigned on the basis of the two‐dimensional spectra. For the unsubstituted cinnamic acid phenyl ester, optimized molecular structures were calculated at a B3LYP/6‐311++G(d,p) level of theory. 1H and 13C NMR chemical shifts were also calculated with the GIAO method at the B3LYP/6‐311 + G(2d,p) level of theory. The comparison between experimental and calculated NMR chemical shift suggests that the experimental spectra are formed from the superposition spectra of the two lowest energy conformers of the compound in solution. The most stable s‐cis configuration found in our studies is also the conformation adopted for a related phenyl cinnamate in solid state. The experimental results were analyzed in terms of the substituent effects. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
1000.
Ratbay?Myrzakulov Diego?Sáez-GómezEmail author Anca?Tureanu 《General Relativity and Gravitation》2011,43(6):1671-1684
In the context of the so-called Gauss–Bonnet gravity, where the gravitational action includes function of the Gauss–Bonnet
invariant, we study cosmological solutions, especially the well-known ΛCDM model. It is shown that the dark energy contribution and even the inflationary epoch can be explained in the frame of
this kind of theories with no need of any other kind of component. Other cosmological solutions are constructed and the rich
properties that this kind of theories provide are explored. 相似文献