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121.
122.
Lobo AO Corat MA Ramos SC Matsushima JT Granato AE Pacheco-Soares C Corat EJ 《Langmuir : the ACS journal of surfaces and colloids》2010,26(23):18308-18314
A method for the electrodeposition of hydroxyapatite films on superhydrophilic vertically aligned multiwalled carbon nanotubes is presented. The formation of a thin homogeneous film with high crystallinity was observed without any thermal treatment and with bioactivity properties that accelerate the in vitro biomineralization process and osteoblast adhesion. 相似文献
123.
Juliana S Luz Celso RR Ramos Márcia CT Santos Patricia P Coltri Fernando L Palhano Debora Foguel Nilson IT Zanchin Carla C Oliveira 《BMC biochemistry》2010,11(1):22
Background
The archaeal exosome is formed by a hexameric RNase PH ring and three RNA binding subunits and has been shown to bind and degrade RNA in vitro. Despite extensive studies on the eukaryotic exosome and on the proteins interacting with this complex, little information is yet available on the identification and function of archaeal exosome regulatory factors. 相似文献124.
Paula Gonçalves Fenga Nelson Ramos Stradiotto Maria Isabel Pividori 《Electroanalysis》2010,22(24):2979-2984
The growth of zinc hexacyanoferrate (ZnHCF) hybrid film on the surface of graphite‐epoxy composite (GEC) electrodes was demonstrated by cyclic voltammetry. Surface morphology of the hybrid film was investigated by using scanning electron microscopy. The effect of the type of monovalent cations on the redox behaviour of hybrid film was also studied. This effect indicated that the radius of the hydrated cation mainly determines the ion permeability of the film. 相似文献
125.
B.G. Oliveira R.C.M.U. Araújo A.B. Carvalho M.N. Ramos 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(2):563-566
B3LYP/6-311++G(d,p) calculations were used to predict some molecular properties of the C2H6N+?BeH2, C2H6N+?MgH2, C3H8N+?BeH2 and C3H8N+?MgH2 dihydrogen-bonded complexes. In these systems, it was demonstrated that the C2H6N+ and C3H8N+ protonated rings are potential candidates to bind with protonic hydrogens derived from alkaline earth metal compounds, BeH2 and MgH2. In terms of structural parameters and quantification of the dihydrogen bond energies, we should mention that the C2H6N+ three-membered ring provides the formation of stronger bound systems, which are 4.0 kJ mol?1 more stables than C3H8N+ four-membered ones. As complement, the analysis of the infrared spectrum indicated that red-shifts and blue-shifts are occurring in the N–H bonds of both C2H6N+ and C3H8N+ cationic rings. However, these two vibrational shifts were also verified on BeH2 and MgH2, what lead us to affirm that cationic compounds derived from small nitrogen rings and earth alkaline molecules are able to form unusual dihydrogen-bonded complexes by means of distinct spectroscopic phenomena, the red-shits and blue-shifts. 相似文献
126.
127.
A.C.A. Ramos G.A. Farias N.S. Almeida 《Physica E: Low-dimensional Systems and Nanostructures》2011,43(10):1878-1881
The effects of nonzero temperature, finite thickness and magnetic fields on an electron gas confined in a quasi-two-dimensional (Q2DEG) region are studied. Finite values of the thickness allow the existence of energy bands and give new characteristics to the system. Here we study some thermodynamic and transport properties to get a better understanding of these effects. For electronic densities of the order of 1012 electrons per cm2, and temperatures lower than 4 K, it is found that the chemical potential, free energy, magnetization, magnetic susceptibility and the inverse of Hall conductivity are independent of the thickness up to it reaches a threshold value. Systems with thicknesses a little above of the critical value lose the two-dimensional character, but they do not have the properties of a three-dimensional electron gas. 相似文献
128.
We present a simple measure of the conductance fluctuations in open ballistic chaotic quantum dots, extending the number of maxima method originally proposed for the statistical analysis of compound nuclear reactions. The average number of extreme points (maxima and minima) in the dimensionless conductance T as a function of an arbitrary external parameter Z is directly related to the autocorrelation function of T(Z). The parameter Z can be associated with an applied gate voltage causing shape deformation in quantum dot, an external magnetic field, the Fermi energy, etc. The average density of maxima is found to be <ρ(Z)>=α(Z)/Z(c), where α(Z) is a universal constant and Z(c) is the conductance autocorrelation length, which is system specific. The analysis of <ρ(Z)> does not require large statistic samples, providing a quite amenable way to access information about parametric correlations, such as Z(c). 相似文献
129.
We study the homology theory of ? - modal maps of the interval. We give another proof of the Milnor and Thurston results
about zeta-functions and we give a functorial approach to kneading theory. Our results give explicit methods for computing
the sequences of lap numbers ? (f
k
) and the sequences of numbers of periodic points in an arbitrary interval [x,y].
Received: 25 February 1998 / Accepted: 15 January 1999 相似文献
130.
Paula Gonçalves Fenga Nelson Ramos Stradiotto 《Journal of Solid State Electrochemistry》2011,15(6):1279-1286
In this work, the electrochemical quartz crystal microbalance has been employed to monitor directly the in situ growth of
the zinc hexacyanoferrate film during the electrodeposition. Mass changes of the platinum|crystal working electrode were correlated
with cyclic voltammetry data. Effects of the sorption of counter-cations (K+, Na+, and NH4+ {\hbox{NH}}_4^{+} and anions (Cl− and SO42 - {\hbox{SO}}_4^{2 - } ) during redox reactions were studied. The electrocatalytic oxidation properties of procaine by the zinc hexacyanoferrate
films were performed. 相似文献