Structural properties of 0.65Pb(Mg1/3Nb2/3)O3–0.35PbTiO3 relaxor ferroelectric thin films on SrRuO3 conducting oxides

Coating of 0.65Pb(Mg_1/3Nb_2/3)O₃–0.35PbTiO₃ (PMN–PT) relaxor ferroelectrics by a sol–gel method is followed by growth of epitaxial SrRuO₃ (SRO) metallic oxide electrodes on SrTiO₃ (STO) single-crystal substrate by pulsed laser deposition. High-quality PMN–PT films on SRO with preferred growth orientation were successfully fabricated by controlling the operation parameters. Structural properties of relaxor ferroelectric PMN–PT thin films on SRO/STO substrates have been studied by X-ray diffraction (XRD), transmission electron microscopy (TEM) and atomic force microscopy (AFM). In-plane and out-of-plane alignments of the heterostructure are confirmed and the structural twinning of the materials are also revealed.     

Biofiltration of toluene in the absence and the presence of ethyl acetate under continuous and intermittent loading

BACKGROUND: Two peat biofilters were used for the removal of toluene from air for one year. One biofilter was fed with pure toluene and the other received 1:1 (by weight) ethyl acetate:toluene mixture. RESULTS: The biofilters were operated under continuous loading: the toluene inlet load (IL) at which 80% removal occurred was 116 g m^?3 h^?1 at 57 s gas residence time. Maximum elimination capacity of 360 g m^?3 h^?1 was obtained at an IL of 745 g m^?3 h^?1. The elimination of toluene was inhibited by the presence of ethyl acetate. Intermittent loading, with pollutants supplied for 16 h/day, 5 days/week, did not significantly affect the removal efficiency (RE). Biomass was fully activated in 2 h after night closures, but 6 h were required to recover RE after weekend closures. Live cell density remained relatively constant over the operational period, while the dead cell fraction increased. Finally, a 15 day starvation period was applied and operation then re‐started. Performance was restored with similar re‐acclimatization period to that after weekend closures, and a reduction in dead cell fraction was observed. CONCLUSION: This study demonstrates the capacity of the system to handle intermittent loading conditions that are common in industrial practices, including long‐term starvation. Copyright © 2008 Society of Chemical Industry     

Multi-step transformation in numerical renormalization group

We compute the temperature dependent magnetic susceptibility of the single-impurity, two-channel Anderson model with an alternative multi-step numerical renormalization-group transformation, previously applied only to the two-impurity single-channel Kondo model. Compared with the traditional transformation, the new procedure requires substantially less memory and computational time, and opens therefore perspectives for the application of the numerical renormalization-group procedure to more complex Hamiltonians.     

Child negative emotionality and parenting from infancy to preschool: A meta-analytic review.

This meta-analytic review (k = 62 studies; N = 7,613 mother-child dyads) shows that effect sizes for the association between child negative emotionality and parenting were generally small and were moderated by sample and measurement characteristics. The association between more child negative emotionality and less supportive parenting was relatively strong in lower socioeconomic status families, reversed in higher socioeconomic status families, and limited to studies with relatively high percentages of participants from ethnic minorities and studies using parent report to assess negative emotionality. Higher levels of child negative emotionality were associated with more restrictive control in samples with less than 75% 1st-born children, as well as in infants and preschoolers, and in studies using parent report or composite measures to assess both negative emotionality and restrictive parenting. Finally, more child negative emotionality was associated with less inductive control. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mapping of Trellises Associated with General Encoders onto High-Performance VLSI Architectures

A rate 1/n binary generic convolutional encoder is a shift-register circuit where the inputs are information bits and the outputs are blocks of n bits generated as linear combinations on the appropriate shift register contents. The decoding of the outputs of a convolutional encoder can be carried out by the well-known Viterbi algorithm. The communication pattern of the Viterbi Algorithm is given as a graph, called trellis, associated to the state diagram of the corresponding encoder. In this paper we present a methodology that permits the efficient mapping of the Viterbi algorithm onto a column of an arbitrary number of processors. This is done through the representation of the data flow by using mathematical operators which present an inmediate hardware projection. A single operator string has been obtained to represent a generic encoder through the study of the data flow of free-forward encoders and feed-back encoders. The formal model developed is employed for the partitioning of the computations among an arbitrary number of processors in such a way that the data are recirculated opimizing the use of the processors and the communications. As a result, we obtain a highly regular and modular architecture suitable for VLSI implementation.     

Application of Methyl Cinnamate/Montmorillonite as Ultraviolet Radiation Shelters

The interaction of methyl cinnamate/montmorillonite samples prepared by melting the former onto the second or by joint grinding, has been studied by x-ray diffraction. differential thermal analysis, thermogravimetric analysis and Fourier-transform infrared spectroscopy. Formation of an interlayer compound has been observed, leading to an increase of 4.15 or 3.42 A (samples obtained by melting or grinding, respectively) in the basal spacing of the clay. Formation of such a complex leads to a displacement of molecular water from the interlayer space, as concluded from the thermal studies. No chemical change is observed in the methyl cinnamate molecule, as confirmed by infrared spectroscopy. The system prepared improve the shelter properties of the clay and the drug separately, mainly in the C zone of the ultraviolet spectrum (290-190 nm).