Search results for " Principi"
showing 10 items of 398 documents
Modelling of a recirculating photocatalytic microreactor implementing mesoporous N-TiO2 modified with graphene
2020
Abstract The use of microreactors in (photo)catalytic processes offers new possibilities for studying and optimizing many mass and photon transfer limited reactions. In this study, we propose a scalable computational fluid dynamics (CFD) model for the prediction of photocatalytic degradation of a model pollutant (4-nitrophenol) using immobilized N-doped TiO2 grown over reduced graphene oxide (N-TiO2/rGO) in a photocatalytic microreactor working in continuous flow-recirculation mode. The mode of operation used in this study allows the reduction of mass transfer limitations inherent to heterogeneous photocatalytic reactions taking place on immobilized catalysts. A CFD model was developed for …
In vitro degradation and bioactivity of composite poly-l-lactic (PLLA)/bioactive glass (BG) scaffolds: comparison of 45S5 and 1393BG compositions
2017
The objective of this study was to compare the effect of two bioglass (BG) compositions 45S5 and 1393 in poly-l-lactic composite scaffolds in terms of morphology, mechanical properties, biodegradation, water uptake and bioactivity. The scaffolds were produced via thermally induced phase separation starting from a ternary polymer solution (polymer/solvent/non-solvent). Furthermore, different BG to polymer ratios have been selected (1, 2.5, 5% wt/wt) to evaluate the effect of the amount of filler on the composite structure. Results show that the addition of 1393BG does not affect the scaffold morphology, whereas the 45S5BG at the highest amount tends to appreciably modify the scaffold archite…
Politika un tiesības: Tiesību un juridiskās prakses ilgtspējīga attīstība
2012
Izdevumā publicēti Apvienotā Pasaules latviešu zinātnieku 3. kongresa un Letonikas 4. kongresa sekcijā „Tiesību un juridiskās prakses ilgtspējīga attīstība” (LU Juridiskā fakultāte, 2011. gada 25. oktobris, Rīga, Raiņa bulvāris 19) nolasītie referāti.
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…
Metafisica come morfologia del principio
2018
The essay analyzes Giuseppe Nicolaci's conception of metaphysic in relation to the Aristotelian determination of prote philosophia and referring to the long exegetical history of metaphysics.
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…
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. …
Il "minor sacrificio necessario" parametro diacronico per tutte le vicende de libertate
2013
Anche in sede cautelare appare opportuno dare attuazione alla sentenza Torregiani, ricorrendo alla misura inframuraria solo quale extrema ratio, a prescindere dalle esigenze di politica criminale e dalle ideologie dominanti
LA SCUOLA OFFICINA MECCANICA PRESSO IL VILLAGGIO MONTE DEGLI ULIVI A RIESI. RICOSTRUZIONE DI UN PROCESSO TRA ANALISI COMPOSITIVE E GRAFICO-GEOMETRICHE
2015
Il presente contributo trae origine da una più ampia ricerca che ha consentito di approfondire la comprensione dei principi progettuali e geometrico-compositivi dell’opera in oggetto; avvalendosi anche di un rilievo scientifico integrato che, attraverso nuove tecniche digitali applicate, ha permesso di condurre una specifica analisi grafico-geometrica sull’impianto architettonico1. L’edificio della scuola officina meccanica, inserito in un più ampio e articolato complesso edilizio2, è composto da una singolare configurazione in pianta ai diversi livelli, oggi non più chiaramente leggibile a causa dei numerosi interventi di trasformazione subiti. I disegni di restituzione grafica, realizzati…