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991.
Two homologues of supramolecular Borromean rings were obtained based on the halogen-bonding-driven self-assembly of iodide ions with telechelic diiodoperfluoroalkanes.  相似文献   
992.
Hydroxyl functional poly(amidoamine) dendron wedges have been reacted with the surface of multi-walled carbon nanotubes and used for templating silver nanoparticles.  相似文献   
993.
We investigate well-posedness in classes of discontinuous functions for the nonlinear and third order dispersive Degasperis-Procesi equation
(DP)  相似文献   
994.
We consider degenerate elliptic equations of p-Laplacean type
$$-{\rm{div}}\, (\gamma(x)|Du|^{p-2}Du)=\mu\,,$$
and give a sufficient condition for the continuity of Du in terms of a natural non-linear Wolff potential of the right-hand side measure μ. As a corollary we identify borderline condition for the continuity of Du in terms of the data: namely μ belongs to the Lorentz space L(n, 1/(p ? 1)), and γ(x) is a Dini continuous elliptic coefficient. This last result, together with pointwise gradient bounds via non-linear potentials, extends to the non homogeneous p-Laplacean system, thereby giving a positive answer in the vectorial case to a conjecture of Verbitsky. Continuity conditions related to the density of μ, or to the decay rate of its L n -norm on small balls, are identified as well as corollaries of the main non-linear potential criterium.
  相似文献   
995.
996.
Surface plasmon resonance imaging is used to demonstrate the recognition by the Ricinus communis agglutinin of a new SOD mimic, a bioconjugate of the manganese(II) complex of 1,4,7,10,13-pentaazacyclopentadecane with galactose.  相似文献   
997.
A practical and straightforward protocol for the preparation of a solution-phase library of acrylonitrile scaffolds is reported. Target compounds were obtained in high yield, stereoselectivity, and purity by two simple and practical steps from cyanoacetic acid. Moreover, our study proposes a synthetic approach starting from the constructed library to obtain three-membered heterocycles.  相似文献   
998.
999.
The purpose of this work is to understand the effect of an external environment on the adiabatic dynamics of a quantum critical system. By means of scaling arguments we derive a general expression for the density of excitations produced in the quench as a function of its velocity and of the temperature of the bath. We corroborate the scaling analysis by explicitly solving the case of a one-dimensional quantum Ising model coupled to an Ohmic bath.  相似文献   
1000.
Photoelectron resonance capture ionization (PERCI) is a soft and sensitive ionization method, based on the attachment of low-energy (<1 eV) photoelectrons to organic analyte molecules. PERCI has been developed in our laboratory for the real-time analysis of organic particles by mass spectrometry, and is employed here to monitor the heterogeneous reaction of ozone with oleic acid. Simplified identification of the reaction products is possible as a result of the soft nature of PERCI, giving predominantly the [M--H](-) ions. The major particle-phase products are identified as: 1-nonanal, nonanoic acid, 9-oxononanoic acid, and azelaic acid, consistent with proposed mechanisms. New insight into this well-studied heterogeneous reaction is gained as additional minor particle-phase products, consistent with the Criegee mechanism, are readily detected.  相似文献   
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