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141.
Influence of ionic liquid composition on the stability of polyvinyl chloride‐based ionic liquid inclusion membranes in aqueous solution 下载免费PDF全文
Francisca Tomás‐Alonso Aurora M. Rubio Alfonso Giménez Antonia P. de los Ríos Maria J. Salar‐García Victor M. Ortiz‐Martínez Francisco J. Hernández‐Fernández 《American Institute of Chemical Engineers》2017,63(2):770-780
Membrane technology has gained significant importance with the incorporation of ionic liquids into their structure. This work shows the influence of ionic liquid composition on the stability of PVC‐based polymer ionic liquid inclusion membranes (PILIMs) in aqueous solution. Among the ILs investigated, those membranes which contain between 20 and 30%w/w of the least soluble, [OMIM+][PF6?] and [OMIM+][Ntf2?], exhibit losses of IL lower than 10%. For both ILs, the amount immobilized was maximum for the membranes with 30%w/w of IL (0.0838 and 0.0832 g, respectively). On the contrary, the ionic liquid loss increases as its solubility in water increase, reaching 99.52% when PILIMs are prepared with 70%w/w of [OMIM+][BF4?]. The results demonstrate that the stability of PILIMs depends on the solubility of the IL in the surrounding phase and the specific interaction between the IL and the polymeric support for PVC‐to‐IL ratios higher than 30%w/w. © 2016 American Institute of Chemical Engineers AIChE J, 63: 770–780, 2017 相似文献
142.
Alfonso Policicchio Raffaele Filosa Salvatore Abate Giovanni Desiderio Elio Colavita 《Journal of Porous Materials》2017,24(4):905-922
The aim of this comprehensive review on materials for methane storage application is to understand which are the best conditions and the best materials for their use for the implementation of storage tank. The research was focused on two different families of samples that up to now appear like the most promising. In particular, Activated carbon and metal organic framework were analyzed and an overall picture was extrapolated. Analysis of the structural parameters and adsorption capacities were evaluated and relation between them were obtained. A comparison of values available in literature was done and, when possible, laboratory tests were performed. The presented results allow to identify potential materials with high specific storage capacity and to verify their performances in optimized conditions. This work represents the starting point for a real and efficient method to the methane storage as a starting point for the development of Adsorbed Natural Gas technology for static and/or automotive applications. 相似文献
143.
A Roadmap for Controlled and Efficient n‐Type Doping of Self‐Assisted GaAs Nanowires Grown by Molecular Beam Epitaxy 下载免费PDF全文
Marta Orrù Eva Repiso Stefania Carapezzi Alex Henning Stefano Roddaro Alfonso Franciosi Yossi Rosenwaks Anna Cavallini Faustino Martelli Silvia Rubini 《Advanced functional materials》2016,26(17):2836-2845
N‐type doping of GaAs nanowires has proven to be difficult because the amphoteric character of silicon impurities is enhanced by the nanowire growth mechanism and growth conditions. The controllable growth of n‐type GaAs nanowires with carrier density as high as 1020 electron cm?3 by self‐assisted molecular beam epitaxy using Te donors is demonstrated here. Carrier density and electron mobility of highly doped nanowires are extracted through a combination of transport measurement and Kelvin probe force microscopy analysis in single‐wire field‐effect devices. Low‐temperature photoluminescence is used to characterize the Te‐doped nanowires over several orders of magnitude of the impurity concentration. The combined use of those techniques allows the precise definition of the growth conditions required for effective Te incorporation. 相似文献
144.
Erythrocytes express the same glucose transporter (GLUT-1) as is present in the blood-brain barrier. With the aim of testing the viability of using this transport system to deliver glucosyl drug derivatives to the brain, the uptake of several dopamine-glucose conjugates and a few structurally related analogues by erythrocytes was studied with HPLC and (1)H MAS NMR spectroscopy. The results showed that slight structural changes determine the uptake of glycoconjugates by red blood cells. However, experiments in the presence of glucose transport inhibitors showed that none of the conjugates that efficiently crossed the cell membrane were transported by GLUT-1. 相似文献
145.
Raúl Sánchez-Vioque Alfonso Clemente Javier Vioque Juan Bautista Francisco Millán 《Journal of the American Oil Chemists' Society》1998,75(7):851-855
The neutral lipids composition of defatted chickpea flour and two types of protein isolates has been studied. The main compounds
in neutral lipids are triacylglycerols, free fatty acids, and diacylglycerols. Other compounds present are wax esters, free
fatty alcohols, and free sterols. The main fatty acids in neutral lipids are C18:2 and C18:1 among the unsaturated, and C16:0 and C18:0 among the saturated acids. Free and esterified alcohols range from C16:0 to C28:0, the majority being those with an even number of carbon atoms. Sterols observed are β-sito-sterol, campesterol, stigmasterol,
and δ-5-avenasterol. Triacyl-glycerols are partially hydrolyzed, and the amounts of unsaturated sterols and unsaturated fatty
acids are reduced as a result of the chemical treatment during production of the protein isolates. 相似文献
146.
Eduardo Méndez Julio Sanhueza Susana Nieto Hernán Speisky Alfonso Valenzuela 《Journal of the American Oil Chemists' Society》1998,75(1):79-83
The oil extracted from the fat-storage organ (fat body) of the bullfrog (Rana catesbeiana) was characterized for its fatty acid composition. The main fatty acids were palmitic (18.1%), stearic (4.1%), myristic (2.7%),
oleic (31.7%), and linoleic (12.9%) acids. Long-chain polyunsaturated fatty acids were also present in significant amounts,
i.e., eicosapentaenoic (1.5%) and docosahexaenoic (4.7%), and were probably derived from the fish meal content of the diet.
A partially fractionated oil was extracted from the homogenized and frozen fat body with an oleic acid content of 43.2%. The
natural alkaloid boldine, added at 0.5 mg/g oil level, improved the oxidative stability by a factor ranging from 1.7 to 2.4,
as assessed by the Oil Stability Index method between 90 and 110°C. The stabilization effect of boldine was higher than that
of naringenin, morin, and quercitin and for the synthetic antioxidant butylated hydroxytoluene at the same concentration level. 相似文献
147.
Picture-word interference experiments conducted with Italian speakers investigated how determiners are selected in noun phrase (NP) production. Determiner production involves the selection of a noun's syntactic features (mass or count, gender), which specify the type of determiner to be selected, and the subsequent selection of a particular phonological form (e.g., the/a in English). The research focused on the syntactic feature of gender. Results repeatedly failed to replicate the gender-congruity effect in NP production reported with Dutch speakers (longer latencies for target-distractor noun pairs with contrasting as opposed to the same gender). It is proposed that the discrepant results reflect processing differences in lexical access in Italian and Dutch: The selection of determiners in Italian, but not in Dutch, depends on phonological properties of the word that follows it in the NP. Evidence consistent with this explanation was obtained in an experiment in which determiner selection in NP production was hindered by conflicting phonological information in the NP. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
148.
Alessandra Passaro Paolo Corvaglia Orazio Manni Luigi Barone Alfonso Maffezzoli 《Polymer Composites》2004,25(3):307-318
This paper reports on the development and the optimization of a thermoforming process (compression molding) for thermoplastic sandwich panels. The skins of the panels are fabricated from polypropylene (PP)/continuous glass fibers dry prepregs in the form of a commingled fabric. The use of two different types of core material has been used, a PP foam and a PP honeycomb. Additionally, two alternative methods for the thermoforming process have been analyzed, using either a one-stage or a two-stage process. In the one-step process, skin molding and skin-core bonding are carried out simultaneously. In the two-stage process, the skins are first thermoformed and then bonded to the core as the second stage. The influence of the selected process parameters on the mechanical properties of the panels has been experimentally investigated, leading to the identification of the preferred processing conditions. Polym. Compos. 25:307–318, 2004. © 2004 Society of Plastics Engineers. 相似文献
149.
150.
Alfonso Ranalli Stefania Contento Carlo Schiavone Nicola Simone 《European Journal of Lipid Science and Technology》2001,103(4):228-238
Three Italian olive varieties (Caroleo, Leccino and Dritta) were processed by centrifugation in the oil mill. The olive paste was kneaded at 20, 25, 30 and 35 °C. The results achieved revealed that the oil content in green volatiles from lipoxygenase pathway (including C5 and C6 compounds and especially unsaturated C6 aldehydes) decreased progressively as the kneading temperature increased, dropping markedly at 35 °C. The content of phenols, o‐diphenols and secoiridoids showed an opposite trend, but the temperature of 35 °C was critical also for them, as it was for the majority of the other components, analytical parameters and indices related to quality, typicality and genuineness. In general, an increasing kneading temperatures increased the release of oil constituents from the vegetable tissue. This factor also affected the oil extraction yields. The best overall results were achieved by malaxing the olive paste at 30 °C. In fact, this temperature level led to achieving both pleasant green virgin olive oils and satisfactory oil extraction outputs. 相似文献