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71.
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73.
Jiménez-Millán E Giner-Casares JJ Muñoz E Martín-Romero MT Camacho L 《Langmuir : the ACS journal of surfaces and colloids》2011,27(24):14888-14899
The surface active derivative of the organic dye Acridine Orange (N-10-dodecyl-acridine orange (DAO)) has been included in mixed Langmuir monolayers with stearic acid (SA). The maximum relative content on DAO for a stable mixed monolayer is a molar ratio of X(DAO) = 0.5. Brewster angle microscopy (BAM) reveals a high homogeneity at the micrometer level for the mixed monolayer in equimolar proportion (X(DAO) = 0.5), whereas the appearance of domains occurs for lower content of DAO, i.e., X(DAO) = 0.2 and 0.1. The aggregation of the DAO headgroup leads to well-defined H-aggregates at the air/water interface for those mixed monolayers with a low content of DAO. However, for the mixed monolayers enriched in DAO, e.g., X(DAO) = 0.5, the molecular crowding prevents the formation of defined supramolecular structures. Molecular organization and tilting of the DAO headgroup is quantitatively analyzed by in situ UV-visible reflection spectroscopy. The formation of H-aggregates of the DAO headgroup can be reversibly tuned with the applied surface pressure. A molecular mechanism for the conformational rearrangement of the DAO molecule is proposed using RM1 quantum semiempirical calculations. 相似文献
74.
Rodrigues JA Oliveira RP Ratusznei SM Zaiat M Foresti E 《Applied biochemistry and biotechnology》2011,163(1):127-142
A study was performed regarding the effect of the relation between fill time, volume treated per cycle, and influent concentration
at different applied organic loadings on the stability and efficiency of an anaerobic sequencing batch reactor containing
immobilized biomass on polyurethane foam with recirculation of the liquid phase (AnSBBR) applied to the treatment of wastewater
from a personal care industry. Total cycle length of the reactor was 8 h (480 min). Fill times were 10 min in the batch operation,
4 h in the fed-batch operation, and a 10-min batch followed by a 4-h fed batch in the mixed operation. Settling time was not
necessary since the biomass was immobilized and decant time was 10 min. Volume of liquid medium in the reactor was 2.5 L,
whereas volume treated per cycle ranged from 0.88 to 2.5 L in accordance with fill time. Influent concentration varied from
300 to 1,425 mg COD/L, resulting in an applied volumetric organic load of 0.9 and 1.5 g COD/L.d. Recirculation flow rate was
20 L/h, and the reactor was maintained at 30 °C. Values of organic matter removal efficiency of filtered effluent samples
were below 71% in the batch operations and above 74% in the operations of fed batch followed by batch. Feeding wastewater
during part of the operational cycle was beneficial to the system, as it resulted in indirect control over the conversion
of substrate into intermediates that would negatively interfere with the biochemical reactions regarding the degradation of
organic matter. As a result, the average substrate consumption increased, leading to higher organic removal efficiencies in
the fed-batch operations. 相似文献
75.
Cinquanta E Ravagnan L Castelli IE Cataldo F Manini N Onida G Milani P 《The Journal of chemical physics》2011,135(19):194501
We perform a systematic investigation of the resonance and vibrational properties of naphthyl-terminated sp carbon chains (dinaphthylpolyynes) by combined multi-wavelength resonant Raman (MWRR) spectroscopy, ultraviolet-visible spectroscopy, and Fourier-transform infrared (FT-IR) spectroscopy, plus ab initio density functional theory (DFT) calculations. We show that the MWWR and FT-IR spectroscopies are particularly suited to identify chains of different lengths and different terminations, respectively. By DFT calculations, we further extend those findings to sp carbon chains end-capped by other organic structures. The present analysis shows that combined MWRR and FT-IR provide a powerful tool to draw a complete picture of chemically stabilized sp carbon chains. 相似文献
76.
Riela S Bruno M Rosselli S Saladino ML Caponetti E Formisano C Senatore F 《Journal of separation science》2011,34(4):483-492
The essential oil of different parts of Ferulago campestris (Bess.) collected in Sicily has been extracted by microwave-assisted hydrodistillation (MAHD) and by classic hydrodistillation (HD). A comparative qualitative-quantitative study on the composition of the oils was carried out. A total of 100 compounds were identified in the oils obtained by MAHD, whereas 88 compounds characterized the HD oils. The most prominent components were, in all different parts of F. campestris and in both extraction methods, 2,4,5-trimethylbenzaldehyde and 2,4,6-trimethylbenzaldehyde isomers; the latter was not previously found. The attempt to evaluate where the oil components are located in all parts of the plant was carried out by means of a kinetic study. Then, electron microscopy observation on the different parts before and after MAHD and HD was performed. 相似文献
77.
Eugenio Hern��ndez Jos�� Mar��a Martell Maria de Natividade 《Constructive Approximation》2011,33(1):1-14
We study the efficiency of the greedy algorithm for wavelet bases in Lorentz spaces in order to give the near best approximation.
The result is used to give sharp inclusions for the approximation spaces in terms of discrete Lorentz sequence spaces. 相似文献
78.
Eugenio P. Balanzario Jorge Sá nchez-Ortiz. 《Mathematics of Computation》2007,76(260):2045-2049
We compute zeros off the critical line of a Dirichlet series considered by H. Davenport and H. Heilbronn. This computation is accomplished by deforming a Dirichlet series with a set of known zeros into the Davenport-Heilbronn series.
79.
The main goal of the present paper is to sharpen some results about the error made when the Wild sums, used to represent the solution of the Kac analog of Boltzmann’s equation, are truncated at the n-th stage. More precisely, in Carlen, Carvalho and Gabetta (J. Funct. Anal.
220: 362–387 (2005)), one finds a bound for the above-mentioned error which depends on (an
Λ+ε). On the one hand, it is shown that Λ, the least negative eigenvalue of the linearized collision operator, is the best possible exponent. On the other hand, ε is an extra strictly positive number and a a positive coefficient which depends on ε too. Thus, it is interesting to check whether ε can be removed from the above bound. According to the aforesaid reference, this problem is studied here by means of the probability distribution of the depth of a leaf in a McKean random tree. In fact, an accurate study of the probability generating function of such a depth leads to conclude that the above bound can be replaced with (a′ n
Λ). 相似文献
80.