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111.
The idea of taking into account environmental impact criteria in the process design becomes a necessity for both the industry and governments, due to increased binding regulations. Moreover, to address the issue of integrating sustainable processes, environmental impact must be weighed and balanced against other concerns, such as economic performance, product quality, and long-term sustainability. Therefore, this study introduces a methodology for environmental impact minimization and optimization of multiple conflicting criteria. A general eco-design method for biomass drying process is proposed. The main target is to develop an assessment computer-aided process engineering tool that compares environmental impacts of different operating conditions and fuel types to support decision-makers for an improved compliance to environmental criterion and sustainability.  相似文献   
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An easy and fast direct polyesterification method using Brønsted acid ionic liquids (BAILs) as both reaction medium and catalyst was investigated. High molar mass polyesters of 12-hydroxydodecanoic acid (up to ) were obtained in good yields at atmospheric pressure and low temperature (90-130 °C) after 10-120 min reaction and without any added catalyst, reaction conditions that are much milder than conventional ones. Ionic liquids composed of an acidic cation bearing sulfonic acid groups and an acidic anion, such as 3-alkyl-1-(butyl-4-sulfonyl)imidazolium hydrogen sulfates, gave better results than ionic liquids containing only an acidic anion, such as 1-alkyl-3-methylimidazolium hydrogen sulfates. The 1/1 BAIL/12-hydroxydodecanoic acid molar ratio was found to yield polymers of the highest molar mass.  相似文献   
114.
Reverse osmosis (RO) is an interesting process to eliminate small organic solutes (carboxylic acids and alcohols) from distillery condensates before recycling them into the fermentation step. This work investigates the influence of transmembrane pressure, pH and volume reduction factor (VRF) on the efficiency of reverse osmosis treatment of condensate from distillery stillage concentration at pilot scale using three pre-selected membranes (CPA2 and ESPA2 from Hydranautics, BW30 from DOW). Performances were assessed according to permeate flux, solutes rejection and abatement of fermentation inhibition. Transmembrane pressure increase leads to an increase of these three parameters with a plateau for rejections and abatement at 20 bar; however, in order to comply with membranes manufacturer's recommendations and to limit or delay polarization and fouling, it was decided to keep the permeate flux below a value of 30 L h−1 m−2. This corresponded to a maximum pressure of 10 bar for CPA2 and ESPA2 membranes and 25 bar for BW30 membrane. pH increase leads to a diminution of permeate flux and an increase of carboxylic acids rejection whatever the membrane; nevertheless, no abatement of fermentation inhibition is observed. Increasing VRF provokes a decrease of the permeate flux. Although local rejections are stable, the mean rejection assessed with the raw condensate (feed) and the mean permeate decreases. However, the fermentation inhibition remains under 10% up to a VRF of 8. BW30 membrane exhibits the highest rejections and inhibition abatement. On the basis of the pilot scale results with the BW30 membrane, a preliminary estimation of the membrane area is proposed for an industrial plant with 100 m3 h−1 of condensate flow rate and the optimized parameters (pressure 25 bar, no pH modification, VRF 4 and 8).  相似文献   
115.
Raman laser studies of detector-grade CdZnTe crystals show an increase in intensity of the Te peaks of the Raman spectra even at very low laser powers. In this study, atomic force microscopy (AFM) was used to characterize the extent of damage to the CdZnTe crystal surface following exposure to the Raman laser. AFM images revealed localized surface damage in the areas exposed to the Raman laser beam. Additional studies using conductive-probe AFM techniques provided localized electrical information for the laser-induced Te-rich areas.  相似文献   
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117.
The objective of this study was to investigate the effect of chemical oxidation on proteolysis susceptibility of myofibrillar proteins. Myofibrils were prepared from pig M. longissimus dorsi and oxidised by a hydroxyl radical generating system. Protein oxidation level was measured by the carbonyl content, free thiol group content and bityrosine formation. Oxidised or non-oxidised myofibrillar proteins were exposed to papain and proteolysis was estimated by fluorescence using fluorescamine. Oxidation of myofibrillar proteins was dependent upon the oxidising agent concentration. Disulfide bridge and bityrosine formation indicated that oxidation by OH° can induce protein polymerization. Electrophoretic study showed that myosin was the protein most sensitive to oxidation. Results showed a direct and quantitative relationship between protein damages by hydroxyl radical and decreased proteolytic susceptibility. Electrophoretic observations suggest that polymerization and aggregation may explain in part decreased susceptibility of myofibrillar proteins to proteolysis.  相似文献   
118.
Additive manufacturing techniques can be used to produce micro‐porous structures with global morphological properties that are highly controlled through robust computer design. Despite these advantages, most of these techniques still hold several functional constraints, resulting from present technical device limits and consequently the inability to control surface morphology at a microscale level. In this study, a novel protocol for surface modification of 3D titanium alloy‐based open porous structures is developed, which applies a combination of chemical etching (CHE) and electrochemical polishing (ECP) using HF‐based solutions. This protocol achieves significant and controllable roughness reduction of additive manufactured 3D Ti6Al4V open porous structures. Chemical etching mainly removes the attached powder grains, while ECP further decreases the roughness. In this way the heterogeneity of the strut surface roughness throughout the full 3D structure is effectively removed.  相似文献   
119.
The effect of suggestive questions on 3- to 5-year old and 6- to 8-year old children's recall of the final occurrence of a repeated event was examined. The event included fixed (identical items) as well as variable items where a new instantiation represented the item in each occurrence of the series. Relative to reports of children who participated in a single occurrence, children's reports about fixed items of the repeated event were more accurate and less contaminated by false suggestions. For variable items, repeated experience led to a decline in memory of the specific occurrence; however, there was no increase in susceptibility to suggestions about details from nontarget occurrences. Although younger children and children who were interviewed a while after the event were more suggestible, respectively, than older children and those interviewed soon after the event, repeated experience attenuated these effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
120.
To find appetite suppressive molecules derived from fish protein hydrolysates, both in vitro and in vivo experiments were performed in order to demonstrate that hydrolysates produced from blue whiting muscle (BWMH) possess satiating properties. Here we demonstrated for the first time that a protein hydrolysate obtained from marine source was able to enhance cholecystokinin (CCK) and glucagon-like peptide-1 (GLP-1) secretion in STC-1 cell line. To demonstrate that these in vitro activities also exist in vivo, we investigated the effect of BWMH preload administration in rats and its repercussion on food intake and metabolic plasma marker levels. Results showed that BWMH reduced the short term food intake which was correlated to an increase in the CCK and GLP-1 plasma levels. Moreover it was demonstrated that the chronic administration of BWMH led to a decrease in the body weight gain.  相似文献   
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