Search results for "stil"

Performance increase of membrane distillation pilot scale modules operating in vacuum-enhanced air-gap configuration

2019

Abstract This paper presents the first experimental evaluation at pilot scale of the operation of vacuum-enhanced air-gap membrane distillation (V-AGMD) using two commercial spiral-wound modules at Plataforma Solar de Almeria's solar desalination test facilities. The main difference between the modules was the channel length (1.5 and 2.7 m) as a result of having different membrane surface area (7.2 m2 and 25.9 m2 respectively) and different number of envelopes. Suction of air from the gap improved the vapour transfer through the membrane pores and the performance of the modules was significantly increased in relation to common air-gap (AGMD) operational mode, especially in the treatment of …

Prediction models to analyse the performance of a commercial-scale membrane distillation unit for desalting brines from RO plants

2018

Abstract Desalting brines from Reverse Osmosis (RO) plants is one of the most promising applications of Membrane Distillation (MD) systems. The development of accurate models to predict MD system performances plays a significant role in the design of this kind of industrial applications. In this paper, a commercial-scale Permeate-Gap Membrane Distillation (PGMD) module was modelled by means of two different approaches: Response Surface Methodology (RSM) and Artificial Neural Networks (ANN). Condenser inlet temperature, evaporator inlet temperature, feed flow rate and feed water salt concentration were selected as inputs of the model, while permeate flux and Specific Thermal Energy Consumpti…

Essential oils as natural additives to prevent oxidation reactions in meat and meat products: A review

2018

Oxidation reactions during manufacturing, distribution, and storage of meat and meat products result in undesirable physicochemical changes and aromas, which leads to detrimental effects on the product quality. This could be translated into the consumer dissatisfaction and economic loss. One of the most common practices to overcome this issue is the incorporation of synthetic antioxidants. However, the increasing health-consciousness of consumers and their preference for natural additives leads to the search of natural alternatives to synthetic antioxidants. A number of essential oils have strong antioxidant properties and are explored as potential alternatives to chemical antioxidants in t…

The impact of moderate wine consumption on health

2014

Wine is a traditional beverage that has been associated with both healthy and harmful effects. Conceptions like the so-called "French paradox" or the beneficial impact of the Mediterranean diet suggest benefit. Wine has a complex composition, which is affected by whether it is red or white or by other variables, like the variety of grapes or others. Alcohol and phenolic compounds have been attributed a participation in the benefits ascribed to wine. The case of alcohol has been extensively studied, but the key question is whether wine offers additional benefits. Resveratrol, a non-flavonoid compound, and quercetin, a flavonol, have received particular attention. There is much experimental w…

Teacher response pursuits in whole class post-task discussions

2020

This paper explores teacher elicitation practices following a perceived absence of a response to an initial inquiry. Specifically, we focus on whole class post-task discussions where a teacher pursues responses in post-first position following students’ non-uptake, and thus makes her orientation toward the expectation of a response publicly available. The data for this study come from 30 h of video-recorded classroom interactions in an English as a medium of instruction university in Turkey. Using Conversation Analysis, this study demonstrates that when confronted with a non-response to her initial elicitation in whole class interaction, in addition to drawing on interactional resources (e.…

A novel TLC based technique for temperature field investigation in MD channel

2011

Role of membrane dynamics processes and exogenous molecules in cellular resveratrol uptake: consequences in bioavailability and activities.

2011

In the fields of nutrition prevention and therapy treatment, numerous studies have reported interesting properties of trans-resveratrol (RSV), a natural polyphenol against pathologies such as vascular diseases, cancers, viral infections and neurodegenerative processes. These beneficial effects are supported by more studies showing the pleiotropic actions of RSV. Nevertheless, a crucial question concerning these effects is how the polyphenol, when applied to an organism, gains access to its targets. In this review, we focus on the biochemical and biological parameters involved in RSV transport, particularly the role of the phospholipid bilayer in RSV uptake (passive diffusion, carrier-mediat…

RELAZIONI TRA FATTORI AMBIENTALI, STILI DI VITA E METABOLISMO ENERGETICO NEI SOGGETTI OBESI

Gut and microbial resveratrol metabolite profiling after moderate long-term consumption of red wine versus dealcoholized red wine in humans by an opt…

2012

Resveratrol exerts a variety of biological and pharmacological activities, which are observed despite its extremely low bioavailability and rapid clearance from the circulation due to extensive sulfation and glucuronidation in the intestine and liver. In order to more accurately quantify all known resveratrol metabolites, a sensitive and optimized analytical assay was developed and validated by pure standards. Methodology improvements aimed to the chromatographic detection of disulfates and sulfoglucuronides, improving resolution of sulfates, by using a buffered solution, with recovery values of resveratrol and its metabolites, even of sulfates, of 99%. The adapted methodology was then appl…

Is it possible to predict late antepartum stillbirth by means of cerebroplacental ratio and maternal characteristics?

2019

Objective: To examine the potential value of fetal ultrasound and maternal characteristics in the prediction of antepartum stillbirth after 32 weeks’ gestation. Methods: This was a retrospective multicenter study in Spain. In 29 pregnancies, umbilical artery pulsatility index (UA PI), middle cerebral artery pulsatility index (MCA PI), cerebroplacental ratio (CPR), estimated fetal weight (EFW), and maternal characteristics were recorded within 15 days prior to a stillbirth. The values of UA PI, MCA PI, and CPR were converted into multiples of the normal median (MoM) for gestational age and the EFW was expressed as percentile according to a Spanish reference range for gestational age. Data fr…