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71.
Morales A. L. Barrero C. A. Jaramillo F. Arroyave C. Greneche J.-M. 《Hyperfine Interactions》2003,148(1-4):135-144
Hyperfine Interactions - This study is focused on properties of goethite related to the inhibition of the corrosion process in low alloy, weathering steels. These steels are characterized by the... 相似文献
72.
V. Dimant R. Gonzalo J.A. Jaramillo 《Journal of Mathematical Analysis and Applications》2009,350(2):680
We relate the moduli of asymptotic uniform smoothness and convexity of a Banach space with the existence of upper and lower ℓp-estimates of sequences in the space. To this end, we introduce two properties which are related to the (mp)-property defined by Kalton and Werner. In this way we obtain a connection between the moduli of asymptotic uniform smoothness and convexity, and compactness or weak-sequential continuity of multilinear mappings. Finally, we give some applications to the existence of analytic and asymptotically flat norms on a Banach space. 相似文献
73.
This research was supported in part by D.G.I.C.Y.T. (Project PB-87-1031), Spain and by U.S.-Spain. Joint Committee (Project CCB-8609/025) 相似文献
74.
Jesús A. Jaramillo 《Archiv der Mathematik》1992,58(4):384-387
Research supported in part by D.G.I.C.Y.T Project PB-87-1031, Spain. 相似文献
75.
Angela?M?Jaramillo Xiangzhong?Zheng Yi?Zhou Defne?A?Amado Amanda?Sheldon Amita?Sehgal Irwin?B?LevitanEmail author 《BMC neuroscience》2004,5(1):3
Background
SLOB binds to and modulates the activity of the Drosophila Slowpoke (dSlo) calcium activated potassium channel. Recent microarray analyses demonstrated circadian cycling of slob mRNA. 相似文献76.
New and higher yielding synthetic routes to N-protected N-methylpyrrole and N-methylimidazole amino acids are introduced to circumvent difficulties associated with established schemes. Key steps in each synthesis include copper-mediated cross-coupling reaction to directly install a carbamate-protected 4-amine in the N-methylpyrrole derivative and effective nitration followed by a one-pot reduction/Boc protection of the amine in the synthesis of the N-Me-imidazole amino acid. 相似文献
77.
Polyethyleneimine‐Coated Gold Nanoparticles: Straightforward Preparation of Efficient DNA Delivery Nanocarriers 下载免费PDF全文
Dr. Mariano Ortega‐Muñoz Prof. M. Dolores Giron‐Gonzalez Prof. Rafael Salto‐Gonzalez Prof. Ana Belen Jodar‐Reyes Samantha E. De Jesus Prof. F. Javier Lopez‐Jaramillo Prof. Fernando Hernandez‐Mateo Prof. Francisco Santoyo‐Gonzalez 《化学:亚洲杂志》2016,11(23):3365-3375
A novel one‐pot method for the synthesis of polyethyleneimine (PEI)‐coated gold nanoparticles (AuPEI‐NPs) that combines the reductant–stabilizer properties of PEI with microwave irradiation starting from hydrogen tetrachloroaurate acid (HAuCl4) and branched PEI 25 kDa (b25kPEI) was explored. The method was straightforward, green, and low costing, for which the Au/PEI ratio (1:1 to 1:128 w/w) was a key parameter to modulate their capabilities as DNA delivery nanocarriers. Transfection assays in CHO‐k1 cells demonstrated that AuPEI‐NPs with 1:16 and 1:32 w/w ratios behaved as effective DNA gene vectors with improved transfection efficiencies (twofold) and significantly lower toxicity than unmodified b25kPEI and Lipofectamine 2000. The transfection mediated by these AuPEI‐NP–DNA polyplexes preferentially used the caveolae‐mediated route for intracellular internalization, as shown by studies performed by using specific internalization inhibitors as well as colocalization with markers of clathrin‐ and caveolae‐dependent pathways. The AuPEI‐NP polyplexes preferentially used the more efficient caveolae internalization pathway to promote transfection, a fact that supports their higher transfection efficiency relative to that of Lipofectamine 2000. In addition, intracellular trafficking of the AuPEI‐NPs was studied by transmission electron microscopy. 相似文献
78.
C. A. Barrero A. L. Morales J. Restrepo G. Pérez J. Tobón J. Mazo-Zuluaga F. Jaramillo D. M. Escobar C. E. Arroyave R. E. Vandenberghe J.-M. Greneche 《Hyperfine Interactions》2001,134(1):141-152
The effects of Cu or Cr ions on the formation of magnetite, which were prepared by two different methods, were studied by 57Fe Mössbauer spectrometry. The first synthesis procedure consisted in an alkaline hydrolysis of ferrous chloride solution in accordance with literature reports. The second method, which was a variation of a reported synthetic route, consisted of a reaction of a 2:1 Fe(II)/Fe(III) solution under alkaline conditions in the presence of an oxidant agent. The samples were also prepared in the presence of chromium or copper chloride solutions. Our results showed that the magnetites obtained via the first procedure exhibits a higher degree of stoichiometry and a better crystalline quality than those prepared by the second route. It seems that the presence of chromium helped the formation of goethite, whereas the presence of copper interfered with it in agreement with other works. We observed that the magnetites obtained in the presence of copper were of poorer crystallinity than the ones obtained with chromium. Finally, the influence of Cu or Cr upon the magnetic and crystalline properties of the two series of magnetites is also presented and discussed. 相似文献
79.
M. García Hernández F. de J. Carrillo Romo A. García Murillo D. Jaramillo Vigueras M. A. Meneses Nava P. Bartolo Pérez G. Chadeyron 《Journal of Sol-Gel Science and Technology》2010,53(2):246-254
Erbium (Er3+) 0.5% mol doped barium titanate (BaTiO3) thin films were elaborated via sol–gel method and dip-coating technique using titanium alkoxide and barium pentanedionate.
Two syntheses were performed [with and without polyvinylpyrrolidone (PVP)] in order to obtain thick films. The BaTiO3:Er3+ thin films prepared from the sol with PVP were elaborated with 1 layer and those without PVP and were elaborated with 17 layers. In both cases, the films
were deposited on silica quartz substrates. Both BaTiO3:Er3+ films presented a cubic phase, as determined by X-ray diffraction. BaTiO3:Er3+ films elaborated with PVP via single-step dip coating produced crack-free films with thicknesses of ~800 nm. SEM micrographs
for the obtained BaTiO3:Er3+ films revealed high homogeneity and density. Mapping images obtained from BaTiO3:Er3+ revealed homogeneous distribution of Er3+ ions on the surface. XPS analyses of the chemical state and chemical environment of the constituent elements in the compositions
showed that Er3+ ions in (Ba1−x
Er
x
)TiO3 are in mixed valence of Er3+/Er2+. The BaTiO3:Er3+-PVP film exhibited luminescent properties under near-infrared excitation, as revealed by green emissions. The BaTiO3:Er3+-PVP film has good potential for optical applications. 相似文献
80.