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131.
The separation of formic (C1), acetic (C2), propionic (C3), and n-valeric (C5) acids in binary water solutions has been studied using a reverse osmosis (RO) membrane pilot plant operating at different temperatures and pressures (usually 21 °C and 1.72 MPa). The RO membrane, which is composite, polyamide and spiral-wound, having a surface area of 2.6 m2, was fed by a solution of 0.5 M of C1, C2 and C3 acids and 0.146 M of C5. The pilot plant was used to simulate a cascade series of RO modules by recycling the permeate flux at the end of each semi-batch run. The influence on the retention coefficient, R, of molecular weight and molar volume, pKa of the different acids was determined. For acetic acid the influence of temperature (T) and transmembrane pressure (ΔP) was also studied, obtaining an inverse and direct good linear correlation for R vs. T and R vs. ΔP, respectively. The results are particularly interesting for acetic acid-water separation, which is an open question in industrial applications. 相似文献
132.
Bandura Albert; Caprara Gian Vittorio; Barbaranelli Claudio; Pastorelli Concetta; Regalia Camillo 《Canadian Metallurgical Quarterly》2001,80(1):125
This longitudinal research examined a structural model of the self-regulatory mechanisms governing transgressive conduct. Perceived academic and self-regulatory efficacy concurrently and longitudinally deterred transgressiveness both directly and by fostering prosocialness and adherence to moral self-sanctions for harmful conduct. The impact of perceived social self-efficacy was mediated through prosocialness. Moral disengagement and prosocialness affected transgressiveness through the mediating influence of irascible affectivity and hostile rumination. Ruminative affectivity, in turn, both concurrently and longitudinally affected transgressiveness. Moral disengagement also contributed independently to variance in transgressiveness over time. This pattern of relations was obtained after controlling for prior transgressiveness. The structural model was replicated across gender and provided a better fit to the data than did several alternative models. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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135.
Novel nanostructured tungsten trioxide (WO3) films with strong photocatalytic activity, have been prepared by a simple sol–gel route from aqueous peroxopolytungstic
acid (PTA) precursor solutions. We demonstrate that films with different morphologies can be synthesized by simply adjusting
the pH of this precursor solution using different mineral acids such as HCl and HC1O4, and that this control of film texture represents a way of optimizing photocurrent yield. The best films produced using these
methods generated anodic photocurrents of 3.8 mA/cm2 for oxidiation of methanol and 2.2 mA/cm
2
for water splitting, under AM1.5 simulated solar illumination. 相似文献
136.
A. Barbetta M. Dentini M.S. DeVecchis P. Filippini G. Formisano S. Caiazza 《Advanced functional materials》2005,15(1):118-124
A new approach for the preparation of hydrophilic and biocompatible porous scaffolds is described. The procedure involves the derivatization of a biopolymer by the introduction of vinylic moieties, formation of a high‐internal‐phase oil‐in‐water emulsion, and its subsequent polymerization. The ensuing materials are characterized by a highly porous morphology represented by pores completely interconnected by a plurality of holes. The hydrophilic and biocompatible nature of these materials make them good candidates for application as scaffolds for tissue engineering. 相似文献
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138.
T-resolution is a binary rule, proposed by Policriti and Schwartz in 1995 for theorem proving in first-order theories (T-theorem proving) that can be seen – at least at the ground level – as a variant of Stickel's theory resolution. In this paper we consider refinements of this rule as well as the model elimination variant of it. After a general discussion concerning our viewpoint on theorem proving in first-order theories and a brief comparison with theory resolution, the power and generality of T-resolution are emphasized by introducing suitable linear and ordered refinements, uniformly and in strict analogy with the standard resolution approach. Then a model elimination variant of T-resolution is introduced and proved to be sound and complete; some experimental results are also reported. In the last part of the paper we present two applications of T-resolution: to constraint logic programming and to modal logic. 相似文献
139.
Caronti A Majjad H Ballandras S Caliano G Carotenuto R Iula A Foglietti V Pappalardo M 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2002,49(3):289-292
A 1.8-mm × 1.8-mm capacitive micromachined ultrasonic transducer (CMUT) element is experimentally characterized by means of optical measurements. Optical displacement measurements provide information on the resonant behavior of the single membranes and also allow us to investigate the dispersion in the frequency spectrum of adjacent membranes. In addition, higher order mode shapes are observed, showing that either symmetrical or asymmetrical modes are excited in CMUT membranes. Laser interferometry vibration maps, combined with quantitative displacement measurements, provide information about the quality and repeatability of the fabrication process, which is a basic requirement for 2D array fabrication for ultrasound imaging 相似文献
140.
Beatriz Martín‐García Davide Spirito Sebastiano Bellani Mirko Prato Valentino Romano Anatolii Polovitsyn Rosaria Brescia Reinier Oropesa‐Nuez Leyla Najafi Alberto Ansaldo Giovanna D'Angelo Vittorio Pellegrini Roman Krahne Iwan Moreels Francesco Bonaccorso 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(52)
Among the large family of transition metal dichalcogenides, recently ReS2 has stood out due to its nearly layer‐independent optoelectronic and physicochemical properties related to its 1T distorted octahedral structure. This structure leads to strong in‐plane anisotropy, and the presence of active sites at its surface makes ReS2 interesting for gas sensing and catalysts applications. However, current fabrication methods use chemical or physical vapor deposition (CVD or PVD) processes that are costly, time‐consuming and complex, therefore limiting its large‐scale production and exploitation. To address this issue, a colloidal synthesis approach is developed, which allows the production of ReS2 at temperatures below 360 °C and with reaction times shorter than 2h. By combining the solution‐based synthesis with surface functionalization strategies, the feasibility of colloidal ReS2 nanosheet films for sensing different gases is demonstrated with highly competitive performance in comparison with devices built with CVD‐grown ReS2 and MoS2. In addition, the integration of the ReS2 nanosheet films in assemblies together with carbon nanotubes allows to fabricate electrodes for electrocatalysis for H2 production in both acid and alkaline conditions. Results from proof‐of‐principle devices show an electrocatalytic overpotential competitive with devices based on ReS2 produced by CVD, and even with MoS2, WS2, and MoSe2 electrocatalysts. 相似文献