Search results for "Thermal methods"
showing 5 items of 5 documents
Review of space charge measurement systems: acoustic, thermal and optical methods
2016
In the last decade, remarkable developments have concerned the methods of space charge measurement in the field of insulation systems diagnostic. In particular, methods based on acoustic and thermal phenomena have been largely used. The present review provides a broad overview on the different techniques used describing, for each of them, the working principle, the main features and the most relevant applications. Further details are provided for the Pulsed Electro-Acoustic (PEA) method, as it seems to be the most used. This article provides more details on its historical evolution, showing evidence for its technological limits and taking into consideration the advantages and drawn from the…
Contributed Review: Review of thermal methods for space charge measurement.
2016
The space charge accumulation phenomenon has garnered great interest over the last two decades because of the increased use of direct current in high voltage electrical systems. In this context, a significant relevance has been achieved by the thermal methods, used for solid dielectrics. This paper presents a review of this non-destructive measurement system used for the measurement of space charge. The thermal pulse method, the thermal step method, and the laser intensity modulation method are described. For each configuration, the principle of operation, the thicknesses analyzed, and the spatial resolution are described, reporting also the main related applications
High Pressure Treatment Effect on Physicochemical and Nutritional Properties of Fluid Foods During Storage: A Review
2012
Abstract: Consumers demand foods that are easy to consume and that are of high nutritional and sensory quality. Therefore, they appreciate the similarity of minimally processed products to fresh products. In recent years, the food industry has shown increased interest in nonthermal preservation technologies, because they provide products of proven quality and can be an alternative to traditional thermal methods, thus increasing added value. This review examines the effects of high pressure processing (HPP) on the nutritional and physicochemical parameters of fluid foods. While some general trends can be observed, the effects of HPP differ not only according to treatment intensity, but also…
Fruit juice sonication: Implications on food safety and physicochemical and nutritional properties
2015
Abstract Over the last years, consumers are increasingly demanding for nutritious, healthy and fresh-like food products, with high organoleptic quality. Nowadays, emerging non-thermal technologies have raised great interest as a viable alternative to the conventional thermal methods, since they have minimal impact on sensorial and nutritional properties of fresh foods. Ultrasound (US) is one of these promising non-conventional processing technologies and it is especially suitable for preservation of fluid foods. US may be used alone or in combination with other preservation techniques, such as mild heat temperatures, high pressures and antimicrobials. Besides, data on inactivation of food m…
Isoniazid cocrystallisation with dicarboxylic acids: vapochemical, mechanochemical and thermal methods
2016
Cocrystallisation with a series of related compounds allows for the exploration of trends and limitations set by structural differences between these compounds. In this work, we investigate how the length of a dicarboxylic acid influences the outcome of cocrystallisation with isoniazid. We have performed a systematic study on the mechanochemical, thermal and solvent vapour-assisted cocrystallisation of aliphatic dicarboxylic acids (C3–C10) with isoniazid. Our results demonstrate that the rate of mechanochemical and vapour-assisted cocrystallisation depends on the acid chain length and shows alternation between odd- and even-chain acids. The results of thermal cocrystallisation showed that t…