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91.
Juárez BH Meyns M Chanaewa A Cai Y Klinke C Weller H 《Journal of the American Chemical Society》2008,130(46):15282-15284
Insights to the mechanism of CdSe nanoparticle attachment to carbon nanotubes following the hot injection method are discussed. It was observed that the presence of water improves the nanotube coverage while Cl containing media are responsible for the shape transformation of the nanoparticles and further attachment to the carbon lattice. The experiments also show that the mechanism taking place involves the right balance of several factors, namely, low passivated nanoparticle surface, particles with well-defined crystallographic facets, and interaction with an organics-free sp2 carbon lattice. Furthermore, this procedure can be extended to cover graphene by quantum dots. 相似文献
92.
93.
Eleonor Harboure Oscar Salinas Beatriz Viviani 《Journal of Fourier Analysis and Applications》2007,13(3):267-284
As Fefferman and Stein showed, there is a tight connection between Carleson measures and BMO functions. In this work we extend
this type of results to the more general scope of the BMOϕ(ω) spaces. As a byproduct a weighted version of the Triebel-Lizorkin space
is introduced, which turns out to be isomorphic to BMO(ω) as in the unweighted case. 相似文献
94.
García-Acosta B García F García JM Martínez-Mañez R Sancenón F San-José N Soto J 《Organic letters》2007,9(13):2429-2432
Polymeric films containing pyrylium derivatives showing a selective color modulation from yellow to red in the presence of the poorly coordinating hydrogen carbonate anion in water at neutral pH have been developed. 相似文献
95.
The validity of the paraxial approximation for laser beams in free space is studied via an integral criterion based on the propagation invariants of Helmholtz and paraxial wave equations. This approach allows one to determine the paraxial limit for beams with nondefined spot size and for beams described by more parameters in addition to typical longitudinal wavelength and transverse waist. As examples, the paraxiality of higher-order Hermite, Laguerre, and Bessel-Gaussian beams was completely determined. This method could be extended to nonlinear optics and Bose condensates. 相似文献
96.
97.
Neumann MG Schmitt CC Prieto KR Goi BE 《Journal of colloid and interface science》2007,315(2):810-813
A method based on the aggregate to monomol emission ratio, I(aggr)/I(monomol), was used to determine the minimal hydrotropic concentration (MHC) of aromatic hydrotropes. The main advantage of this method is that it does not require the use of probes or other additives, which might disrupt the aggregation process. Also, it relies on spectrophotometric measurements, which are more sensitive and less arduous than others, like conductivity, light scattering and surface tension. 相似文献
98.
Ademar B. Lugao Lucia Noda Elisabeth. C. L. Cardoso Beatriz Hustzler Shinichi Tokumoto Ana Nery F. Mendes 《Radiation Physics and Chemistry》2002,63(3-6):509-512
It is well known that polypropylene undergoes simultaneous crosslinking and degradation under irradiation. However, there are speculations regarding the formation of branching under special conditions. It is also well known that the melt-strength property of a polymer increases with molecular weight and with long-chain branching due to the increase in the entanglement level. This study was a contribution to the understanding of the following points: the role of molecular weight, the role of structural modifications on nucleation properties; the structural changes on polypropylene.
The results showed that degradation was the major reaction in the initial step of irradiation, however, the largely modified molecules concentrated in the high molecular weight fraction. The results also confirm that the branching formation is likely to occur. 相似文献
99.
Shirley M.M. Rodrigues Viviani NardiniMauricio G. Constantino Gil Valdo J. da Silva 《Tetrahedron letters》2012,53(45):6136-6137
The treatment of cerium metal with ethyl bromosuccinate (1) forms the stabilized organolanthanoid intermediate (2), which reacts with carbonyl compounds in a Reformatsky-type reaction, under mild conditions, to produce functionalized γ-substituted paraconic acids (4) in good yields. 相似文献
100.
Kleij AW Souto B Pastor CJ Prados P de Mendoza J 《The Journal of organic chemistry》2003,68(22):8711-8714
The selective preparation and complete structural characterization of a small series of 1,2-anti-heterodisubstituted calix[4]arenes has been accomplished. These compounds were obtained in two steps from unsubstituted p-tert-butylcalix[4]arene by tribenzoylation and a subsequent one-pot, two-step sequence involving alkylation with simultaneous partial deacylation, resulting in heterodisubstituted calixarenes carrying an alkyl and an aroyl group. The monoalkyl-tribenzoyl intermediate, prior to in situ deprotection, could also be isolated. 相似文献