Search results for "resin"

Accuracy of four digital scanners according to scanning strategy in complete-arch impressions.

2018

STATEMENT OF PROBLEM:Although there are specific and general digital scanning guidelines depending on the system used, it is important to have the necessary flexibility in the acquisition of three-dimensional (3D) images to adapt to any clinical situation without affecting accuracy. PURPOSE:The purpose of this in vitro study was to identify and compare the scanning strategy with the greatest accuracy, in terms of trueness and precision, of four intraoral scanners in the impression of a complete dental arch. MATERIAL AND METHODS:Four digital scanners were evaluated with a 3D measuring software, using a highly accurate reference model obtained from an industrial scanner as a comparator. Four …

INCREMENTO DELLA SELETTIVITÀ NELLA SEPARAZIONE DI ANTOCIANINE DA PROANTOCIANIDINE MEDIANTE RESINE

2004

Influence of Nylon 6,6 nanofiber mats on cure behavior and properties of CFR epoxy resin

2014

In this work Nylon 6,6 nanofibrous mats produced by electrospinning were used as interlayers in carbon fiber reinforced laminates. A high crossilinked epoxy resin was chosen as matrix. The effects of polymeric mats on cure behavior, thermal and delamination properties of the composite laminates were investigated.

ANALISI DELLO STATO TENSIONALE IN RESINE EPOSSIDICHE SOTTOPOSTE AD INVECCHIAMENTO IDROTERMICO MEDIANTE TECNICA FOTOELASTICA

2014

In questo lavoro si è analizzato lo stato tensionale che nasce in sistemi epossidici DGEBA quando sono sottoposti ad invecchiamento idro-termico, tramite la tecnica fotoelastica a trasmissione, basata sul metodo a variazione di fase di Compensazione di Tardy. I provini, monitorati ad intervalli di tempo regolari durante i processi di assorbimento e desorbimento di acqua, sono stati osservati al polariscopio circolare. La tecnica ha permesso di analizzare, sia qualitativamente, sia quantitativamente, lo stato tensionale indotto dal non uniforme “swelling” durante l’intero processo di invecchiamento. Inoltre, lo studio ha analizzato anche provini criccati di tipo Single Edge Notched Bending; …

Epoxy resin-thermoplastic blends cured by ionising radiation. Structure/properties relationships

2009

Radiation curing of an epoxy resin based blend is carried out in order to produce polymer matrices for high-performance composites. A suitable choice of both curing process and formulation parameters allows to irradiate at about 60°C. Moreover hydrothermal ageing is performed on cured materials and their properties have been evaluated

Analisi reologica di una resina epossidica utilizzata come adesivo per giunzioni miste

2012

Nanocarbon broadband analysis, temperature dependent dielectric properties and percolation thresholds

2013

The results of a broadband dielectric investigation of multi-walled CNT (MWCNT)/epoxy resin composites in wide temperature range from room temperature to 450 K are reported. Far below the percolation threshold (0.25 wt% MWCNT) the dielectric properties of the composite are mostly determined by alpha relaxation in pure polymer matrix. Close to the percolation threshold the composite shows the negative temperature coefficient (NTC) effect in the temperature region, where the pure polymer matrix becomes conductive. The activation energy increases with the MWCNT concentration far below the percolation threshold and decreases close to it (1.5 wt% MWCNT). The dielectric analysis of the MWCNT/epox…

The Role of Cork Powder as a Filler for Epoxy Putties Used as Gap Fillers of Wood

2009

Techno-economic assessment of multi-effect distillation process for the treatment and recycling of ion exchange resin spent brines

2019

Abstract A treatment chain including nanofiltration, crystallization and multi-effect distillation (MED) is for the first time proposed for the treatment of an effluent produced during the regeneration of Ion Exchange resins employed for water softening. The goal is to recover the minerals and to restore the regenerant solution to be reused in the next regeneration cycle. MED is the most crucial unit of the treatment chain from an economic point of view. A techno-economic analysis on the MED unit was performed and a novel performance indicator, named Levelized Brine Cost, was introduced as a measure of the economic feasibility of the process. Different scenarios were analysed, assuming diff…

A pilot-plant for the selective recovery of magnesium and calcium from waste brines

2021

Abstract The problem of brines disposal has raised great interest towards new strategies for their valorisation through the recovery of minerals or energy. As an example, the spent brine from ion exchange resins regeneration is often discharged into rivers or lakes, thus impacting on the process sustainability. However, such brines can be effectively reconcentrated, after removal of bivalent cations, and reused for the resins regeneration. This work focuses on developing and testing a pilot plant for selective recovery of magnesium and calcium from spent brines exploiting a novel proprietary crystallization unit. This is part of a larger treatment chain for the complete regeneration of the …