Search results for " ingegneria"

A Dialysis Photocatalytic Reactor for the Green Production of Vanillin

2020

In the present work, dialysis was used to recover vanillin while being produced by partial photocatalytic oxidation of ferulic acid in an aqueous solution at ambient temperature. The relatively high value of the permeate flux through a dense polyether-block amide membrane allowed continuously extracting vanillin from the reacting solution, thus avoiding its successive oxidation. The rate of vanillin formation was improved, compared to other reactor configurations, because intermediate compounds permeated from the reacting solution and did not hinder the reaction, while ferulic acid permeated in the opposite direction to partially replenish the reactor with the substrate. The photocatalytic …

Heterogeneous Photocatalysis and Photoelectrocatalysis: From Unselective Abatement of Noxious Species to Selective Production of High-Value Chemicals

2015

Heterogeneous photocatalysis and photoelectrocatalysis have been considered as oxidation technologies to abate unselectively noxious species. This article focuses instead on the utilization of these methods for selective syntheses of organic molecules. Some promising reactions have been reported in the presence of various TiO2 samples and the important role played by the amorphous phase has been discussed. The low solubility of most of the organic compounds in water limits the utilization of photocatalysis. Dimethyl carbonate has been proposed as an alternative green organic solvent. The recovery of the products by coupling photocatalysis with pervaporation membrane technology seems to be a…

Uncontrolled methane emissions from a MSW landfill surface: Influence of landfill features and side slopes

2013

Sanitary landfills for Municipal Solid Waste (MSW) disposal have been identified as one of the most important anthropogenic sources of methane (CH4) emissions; in order to minimize its negative effects on the environment, landfill gas (LFG) recovery is a suitable tool to control CH4 emissions from a landfill site; further, the measurement of CH4 emissions can represent a good way to evaluate the effectiveness of LFG recovering systems. In general, LFG will escape through any faults in the landfill capping or in the LFG collection system. Indeed, some areas of the capping can be more permeable than others (e.g. portions of a side slope), especially when considering a temporarily capped zone …

Computational modeling and experimental characterization of fluid dynamics in micro-CT scanned scaffolds within a multiple-sample airlift perfusion b…

2023

The perfusion of flow during cell culture induces cell proliferation and enhances cellular activity. Perfusion bioreactors offer a controlled dynamic environment for reliable in vitro applications in the tissue engineering field. In this work, to evaluate the effects of the operating parameters of a custom-made bioreactor, numerical simulations were performed to solve the fluid velocity profile inside the bioreactor containing multi-grid support that allows allocating of multiple seeded scaffolds at the same time. The perfusion system exhibited a uniform distribution of liquid velocities within the regions, suitable for cell growth on seeded scaffolds. The effects of the porous microstructu…

Preliminary evaluation of biopolymers production by mixed microbial culture from citrus wastewater in a MBR system using respirometric techniques

2021

Abstract This preliminary study was aimed at evaluating the feasibility to produce biopolymers (BP) from citrus wastewater by mixed microbial culture in an anaerobic/aerobic membrane bioreactor (A/O-MBR). The activated sludge of the A/O-MBR was successfully enriched in microorganisms having a good capacity in producing intracellular biopolymers. The production of BP was found to be about 0.55 mgCOD mgCOD−1 using pure acetate at a concentration of 1000 mgCOD L−1. When using fermented wastewater, the conversion of acetate into BP product was 0.56 mgCOD mgCOD−1 in the test performed with C/N equal to 1000:1, whereas it was only 0.12 mgCOD mgCOD−1 in the test with C/N of 100:5. The results achi…

An integrated Tissue Engineering approach to Human Bronchial model: Biodegradable Scaffold and Microfluidics Platform

L’ingegneria tissutale è la combinazione di cellule, materiali e metodi di ingegneria, insieme con opportuni fattori biochimici e fisico-chimici, volta a migliorare o sostituire le funzioni biologiche di tessuti danneggiati [1, 2]. A tal proposito supporti porosi e sistemi microfluidici sono utilizzati per scopi di ingegneria tissutale. Scaffold polimerici biodegradabili sono stati sfruttati come supporti strutturali per rigenerare vari tessuti quali ossa, cartilagini, nervi, legamenti, pelle e fegato. Una geometria porosa aperta con canali interconnessi è un prerequisito per la crescita cellulare ad alta densità e per un trasporto di nutrienti, ossigeno e prodotti di scarto metabolici. …

Simplified model to evaluate the fate of micropollutants in an integrated urban drainage system: sensitivity analysis

2016

The paper presents the sensitivity analysis of an integrated urban water quality system by means of the global sensitivity analysis (GSA). Specifically, an home-made integrated model developed in previous studies has been modified in order to include the micropollutant assessment (namely, sulfamethoxazole - SMX). The model takes into account also the interactions between the three components of the system: sewer system (SS), wastewater treatment plant (WWTP) and the receiving water body (RWB). The analysis has been applied to an experimental catchment nearby Palermo (Italy): the Nocella catchment. Five scenarios each characterized by different combinations of sub-systems (i.e., SS, WWTP and…

Occurrence and transformation of illicit drugs in wastewater treatment plants.

2016

Illicit drugs (IDs) and their metabolites have been recently recognized as a new group of water emerging contaminants (ECs) with potent psychoactive properties and unknown effects to the aquatic environment (Pal et al., 2013). IDs are excreted via urine and feces and arrive at wastewater treatment plants (WWTPs) where can reach ppb levels (Castiglioni et al., 2006). Over the past few years, it has been demonstrated that conventional biological processes in WWTPs are not or scarcely able to remove IDs. Thus, they are discharged into water bodies through the treated effluent (Postigo et al., 2011). Therefore, monitoring the IDs concentration in WWTPs can have a twofold advantage: i. increase …

TREATMENT OF WEEE - WASTE OF ELECTRIC AND ELECTRONIC EQUIPMENTS - BY MICROWAVE - INDUCED PYROLYSIS

Understanding the Drivers of the Daily App Rank: The Role of Revenue Models

2015

In this paper, based on data from two major app stores (Apple Store and Google Play), we study the role of several revenue models adopted by developers in the success of an app measured in terms of daily rank.