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181.
Cara C Romero I Oliva JM Sáez F Castro E 《Applied biochemistry and biotechnology》2007,137(1-12):379-394
Olive tree pruning generates an abundant, renewable lignocellulose residue, which is usually burnt on fields to prevent propagation of vegetal diseases, causing economic costs and environmental concerns. As a first step in an alternative use to produce fuel ethanol, this work is aimed to study the pretreatment of olive tree pruning residues by liquid hot water. Pretreatment was carried out at seven temperature levels in the range 170-230 degrees C for 10 or 60 min. Sugar recoveries in both solid and liquid fractions resulting from pretreatment as well as enzymatic hydrolysis yield of the solid were used to evaluate pretreatment performance. Results show that the enzyme accessibility of cellulose in the pretreated solid fraction increased with pretreatment time and temperature, although sugar degradation in the liquid fraction was concomitantly higher. 相似文献
182.
Flávio Lopes Alves Roberto C. Sallai Bruno R. Salu Antonio Miranda Maria Luiza V. Oliva 《Natural product research》2016,30(23):2712-2715
Araucaria angustifolia seeds are characterised by a relatively high content of starch and protein. This study aimed to verify the presence of α-amylase inhibitors in the seeds and to characterise a trypsin inhibitor found in the embryo tissues. Inhibitor purification was carried out by the saline extraction of proteins, acetone precipitation and affinity chromatography. Two protein bands of molecular weight estimated by SDS-PAGE at about 35 kDa were further examined by high-performance liquid chromatography coupled to a mass spectrometer and were shown to be 36.955 Da (AaTI-1) and 35.450 Da (AaTI-2). The sequence of the N-terminal region shows that AaTI-1 and AaTI-2 are structurally similar to plant inhibitors of the serpin family. A mixture of AaTI-1 and AaTI-2, identified as AaTI, shows selectivity for the inhibition of trypsin (Kiapp 85 nM) and plasmin (Kiapp 7.0 μM), but it does not interfere with the chymotrypsin, human plasma kallikrein, porcine kallikrein or other coagulation enzymes activity. 相似文献
183.
T. Melia A. de la Oliva I. Soto P. Serrano R. Aguiar 《Wireless Personal Communications》2007,43(3):959-974
The concept of network controlled handovers is commonly used in cellular technologies. With multi-mode terminals, using layer-2
techniques, this concept can only be applied inside each technology, which impairs the full exploitation of multi-access support.
We discuss a layer-3 technique able to operate across technologies, and present an analysis of the performance advantages
this technique brings. In general, an increase around 25% in system usage is achievable. The paper further analyses some cell
characteristics that impact on the performance improvements achievable by network controlled handovers. 相似文献
184.
E. Brigatti M. Nú?ez-López M. Oliva 《The European Physical Journal B - Condensed Matter and Complex Systems》2011,81(3):321-326
We perform an analysis of a recent spatial
version of the classical Lotka-Volterra model, where a finite
scale controls individuals’ interaction. We study the
behavior of the predator-prey dynamics in physical spaces higher
than one, showing how spatial patterns can emerge for some values
of the interaction range and of the diffusion parameter. 相似文献
185.
We report measurements of the dose dependence of the sputtering of evaporated films by 30 keV ions under UHV. An initial (sub-monolayer) enhanced sputtering is attributed to the removal of weakly bound atoms; this enhancement does not depend on the incidence angle of the projectile. 相似文献
186.
187.
188.
María Moreno Oliva Ted M. Pappenfus Dr. Jacob H. Melby Kathryn M. Schwaderer Jared C. Johnson Kari A. McGee Dr. Demetrio A. da Silva Filho Dr. Jean‐Luc Bredas Prof. Juan Casado Dr. Juan T. López Navarrete Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(23):6866-6876
We have prepared a new series of mixed thiophene–pyrrole oligomers to investigate the electronic benefits arising from the combination of these two heterocycles. The oligomers are functionalized with several hexyl and aryl groups to improve both processability and chemical robustness. An analysis of their spectroscopic (absorption and emission), photophysical, electrochemical, solid state, and vibrational properties is performed in combination with quantum‐chemical calculations. This analysis provides relevant information regarding the use of these materials as organic semiconductors. The balance between the high aromatic character of pyrrole and the moderate aromaticity of thiophene allows us to address the impact of the coupling of these heterocycles in conjugated systems. The data are interpreted on the basis of the aromaticity, molecular conformations, ground and excited electronic state structures, frontier orbital topologies and energies, oxidative states, and quinoidal versus aromatic competition. 相似文献
189.
A method for non-intrusively monitoring the polarization dependent loss (PDL) of an installed fiber-optic transmission system is proposed using live dense wave division multiplexing (DWDM)-based traffic as the probing signal. The method extracts the statistical parameters of system PDL from the measured partial PDL data. Field measurements of PDL were performed on long-haul DWDM systems deployed in Sprint’s network and the results validated our theoretical model. 相似文献
190.
E. Oliva F. Dimroth A. W. Bett 《Progress in Photovoltaics: Research and Applications》2008,16(4):289-295
Photovoltaic power converters can be used to generate electricity directly from laser light. In this paper we report the development of GaAs PV power converters with improved conversion efficiency at high power densities. The incorporation of a lateral conduction layer (LCL) on top of the window layer resulted in a considerable gain in efficiency at high illumination levels. Additional performance improvements were obtained by using a metal electrode grid design and antireflection coating optimised for monochromatic and inhomogeneous laser light. Maximum monochromatic (810 nm) optical‐to‐electrical conversion efficiency of 54·9% at 36·5 W/cm2 has been achieved. The characteristics of laser power converters with p/n and n/p polarity are discussed in this paper. Moreover, different materials and doping levels were applied in the LCL. The performance of these different device structures at high laser intensity is presented and discussed. It is shown that the lateral series resistance of the cell has a major impact on the overall device performance. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献