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71.
Licciardi M Cavallaro G Di Stefano M Fiorica C Giammona G 《Macromolecular bioscience》2011,11(3):445-454
A new PHEA‐IB‐PMANa+ copolymer has been synthesized and its pH‐induced self‐assembly has been investigated in an aqueous medium. PHEA‐IB‐PMANa+ formed nanoparticles with diameters from 25 to 50 nm upon protonation of the carboxylic acid moieties dislocated along the grafted polymethacrylate sodium salt side chains. The physico‐chemical characterization of the nanoparticles was performed using light scattering, zeta‐potential measurements, SEM, and AFM. Doxorubicin‐loaded nanoparticles were prepared and drug release profiles were evaluated under conditions mimicking physiological media. A biological characterization was carried out by testing the cytotoxicity on Caco‐2 cells, and cellular uptake on mouse monocyte macrophage (J774 A.1) and Caco‐2 cells.
72.
In this paper we develop a new method to prove the existence of minimizers for a class of constrained minimization problems on Hilbert spaces that are invariant under translations. Our method permits to exclude the dichotomy of the minimizing sequences for a large class of functionals. We introduce family of maps, called scaling paths, that permits to show the strong subadditivity inequality. As byproduct the strong convergence of the minimizing sequences (up to translations) is proved. We give an application to the energy functional I associated to the Schrödinger-Poisson equation in R3
iψt+Δψ−(|x|−1?2|ψ|)ψ+|ψ|p−2ψ=0 相似文献
73.
Francesco P. Ballistreri Gaetano A. Tomaselli Rosa M. Toscano 《Tetrahedron letters》2008,49(20):3291-3293
Aromatic and aliphatic thiols are oxidized in acetonitrile at 20 °C by hydrogen peroxide in the presence of methyltrioxorhenium as the catalyst to yield the corresponding sulfonic acids in high isolated yields (85-94%). 相似文献
74.
Salvatore Occhipinti Gaetano Alberghina Salvatore Fisichella Orazio Puglisi Leopoldo Ceraulo 《Journal of mass spectrometry : JMS》1980,15(12):632-636
The 70 eV electron impact mass spectra of twelve 5- and 3-substituted thiophene-2-carboxamides are discussed with the aid of exact mass measurements and labelling experiments. All mass spectra exhibit pronounced molecular ions. Some isomeric 5- and 3-substituted title compounds can be differentiated by mass spectrometry. The fragmentation is influenced by a strong ‘ortho-effect’ which activates the NH3 elimination. In the other cases the most important fragmentation is NH2˙ loss, followed by CO elimination. 相似文献
75.
76.
77.
Anna Maria Almerico Girolamo Cirrincione Enrico Aiello Gaetano Dattolo 《Journal of heterocyclic chemistry》1989,26(6):1631-1633
A general method for the preparation of 3-amino-1-methylpyrroles in excellent yields is reported. The key step involves the N-methylation of the nitro derivatives 2 , under phase transfer catalysis conditions. 相似文献
78.
Gaetano Fiore 《Communications in Mathematical Physics》1995,169(3):475-500
We realize the Hopf algebraU
q–1
(so(N)) as an algebra of differential operators on the quantum Euclidean spaceR
q
N
. The generators are suitableq-deformed analogs of the angular momentum components on ordinaryR
N
. The algebra Fun(R
q
N
) of functions onR
q
N
splits into a direct sum of irreducible vector representations ofU
q–1
(so(N)); the latter are explicitly constructed as highest weight representations. 相似文献
79.
Francesco Chiadini Antonio Scaglione Gaetano Panariello 《Optical and Quantum Electronics》2004,36(11):981-995
A numerical method for calculating cutoff frequencies of modes of weakly guiding optical fibers is described. Starting from a properly constructed field representation, the method follows a variational approach to obtain an eigenvalue problem for the cutoff frequencies which can be easily solved by a standard numerical routine. The field representation uses an expansion in terms of the Laguerre–Gauss functions in the fiber core and limiting form for small arguments of modified Bessel functions in the fiber cladding. Fibers with power-law refractive index profiles and fibers with a profile showing a dip on the axis are analyzed. Results obtained for modes of arbitrary order (both azimuthal and radial) show that our method is very efficient and accurate. 相似文献
80.
A (K4 ? e)‐design on v + w points embeds a P3‐design on v points if there is a subset of v points on which the K4 ? e blocks induce the blocks of a P3‐design. It is shown that w ≥ ¾(v ? 1). When equality holds, the embedding design is easily constructed. In this paper, the next case, when w = ¾v, is settled with finitely many exceptions. © 2003 Wiley Periodicals, Inc. J Combin Designs 11: 352–366, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/jcd.10044 相似文献