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The main objective of this experimental investigation is to assess the effect of thermal and cryogenic treatment on hygrothermally conditioned glass fibre reinforced epoxy matrix composites, and the impact on its mechanical properties with change in percentage of individual constituents of the laminates.

The present investigation is an attempt at evaluating the performance of the laminates subjected to different thermal and cryogenic treatments for varying time with prior hygrothermal treatment. The variability of hygrothermal exposure is in the range of 4‐64 h. Glass fibre reinforced plastics laminates with different weight fractions 0.50‐0.60 of fibre reenforcements were used. The ILSS, which is a matrix dominated was studied by three‐point bend test using INSTRON 1195 material testing machine.

The post‐hygrothermal treatments (both thermal and cryogenic exposures) resulted in an increase in the rate of desorption of moisture. It is noted that the hygrothermal treatment prior to the exposure to thermal or cryogenic conditioning is the major attribute to the variations in the ILSS values. The extent of demoisturisation of the hygrothermally conditioned composites due to a thermal or a cryogenic exposure is observed to be inversely related to its ILSS, independent of the fibre‐weight fractions. Also the ILSS is inversely related to the fibre‐weight fraction irrespective of the post‐hydrothermal treatment.

The reported data are based on experimental investigations.

The purpose of this paper is to investigate the decomposition behavior of binary mixtures of organic activators commonly used in the no-clean wave flux systems upon their exposure to thermal treatments simulating wave soldering temperatures. The binary blends of activators were studied at varying ratios between the components.

Differential scanning calorimetry and thermogravimetric analysis were used to study the characteristics of weak organic acid (WOA) mixtures degradation as a function of temperature. The amount of residue left on the surface after the heat treatments was estimated by gravimetric measurements as a function of binary mixture type, temperature and exposure time. Ion chromatography analysis was used for understanding the relative difference between decomposition of activators in binary blends. The aggressivity of the left residue was assessed using the acidity indication gel test, and effect on reliability was investigated by DC leakage current measurement performed under varying humidity and potential bias conditions.

The results show that the typical range of temperatures experienced by electronics during the wave soldering process is not sufficient for the removal of significant activator amounts. If the residues contain binary mixture of WOAs, the final ratio between the components, the residue level and the corrosive effects depend on the relative decomposition behavior of individual components. Among the WOA investigated under the conventional wave soldering temperature, the evaporation and removal of succinic acid is more dominant compared to adipic and glutaric acids.

The findings are attributed to the chemistry of WOAs typically used as flux activators for wave soldering purposes. The results show the importance of controlling the WOA content and ratio between activating components in a flux formulation in relation to its tendencies for evaporation during soldering and the impact of its residues on electronics reliability.

The results show that the significant levels of flux residues can only be removed at significantly higher temperatures and longer exposure times compared to the conventional temperature range used for the wave soldering process. The potential corrosion issues related to insufficient flux residues removal will be determined by the residue amount, its composition and ratio between organic components. The proper time of thermal treatment and careful choice of fluxing formulation could ensure more climatically reliable product.

Thermal Tour As had been identified in the Second Report on Italian Tourism (1), the market for “thermal tourism” has developed its trends with further characterizations and differentiations:

This research aims to evaluate the antioxidant potential of oregano extract (OE), as well as its isolated and synergistic effect when applied to soybean oil (SO) under thermal oxidation.

In order to determine the antioxidant activity of oregano extract and its synergistic effect with tert‐butylhydroquinone (TBHQ), thermal oxidation was performed using the following treatments: SO, SO with 50 mg/kg of TBHQ, SO with 3,000 mg/kg of OE, and SO with 3,000 mg/kg of oregano extract and 50 mg/kg of TBHQ (mixture). The treatments underwent heating at 180°C for 20 hours, and analyses of oxidative stability, total polar compounds, tocopherols and fatty acids composition were performed. The results obtained were subjected to analysis of variance and Tukey test for averages at 5 percent, using the program ESTAT version 2.0.

Considering the results of antioxidant activity and total phenolic compounds, it was possible to verify that the ethanolic extract of oregano has presented antioxidant potential. Furthermore, considering the results obtained in the analyses of oxidative stability, polar compounds, tocopherols and fatty acids profile, it was possible to observe that the extract has prevented lipid oxidation when added to SO.

The study offers information on the use of natural antioxidants as an alternative to the use of synthetic antioxidants, which can be considered toxic.

The aim of this study was to fabricate polyimide (PI)/Al₂O₃ composite films via surface modification and ion exchange techniques, and examine their properties.

The method involves hydrolyzing the PI film double surface layers in an aqueous potassium hydroxide (KOH) solution and incorporating aluminium ions (Al3+) into the hydrolyzed layers of the PI film via subsequent ion exchange, followed by a treatment of the Al3+-loaded PI films with an aqueous ammonia solution, which leads to the formation of Al(OH)₃ in the surface-modified layers. After a final thermal annealing treatment in ambient air, the Al(OH)₃ decomposes to Al₂O₃, and forms composite layers on both surfaces of the re-imidized PI film.

The PI/Al₂O₃ composite film obtained with a 6 hours of KOH treatment exhibited excellent thermal stability, good mechanical properties and better electric breakdown strength and corona-resistance properties than the pristine PI film.

The method for obtaining the composite films in this paper is worth consideration, but additional research will be needed. Furthermore, this method is of general importance for the fabrication of composite PI films with tailored properties.

This study showed that surface modification and ion-exchange techniques are powerful methodologies for the fabrication of PI/Al₂O₃ composite films.

The purpose of this paper is to analyze microstructural integrity at the interface and consequent implicating effect on mechanical behavior of fiber‐reinforced polymer composites.

In the light of Fourier transform infrared spectroscope (FTIR imaging) and temperature‐modulated differential scanning calorimeter, a sorption mechanism was established. Thermal spike and thermal shock treatment was carried out at 150 and 80°C, respectively. This suggested that fiber/matrix adhesion rests on the structure and properties of both the fiber and matrix in the region near the interface during the hygrothermal treatment.

The carbon surface was found to selectively absorb the tertiary amine catalyst and to modify the chemical state of the cured resin apparently through the effects of absorbed water. The higher values of glass transition temperature (Tg) resulted in longer immersion time and higher exposure temperature. Together, these techniques provide a comprehensive picture of chemical and physical changes at the interphase region. Thermal spike of hybrid composite at 150°C temperature might possibly improve the adhesion level at the interface. Whereas, in case of thermal shock treatment at 80°C the fall in inter‐laminar shear strength value at higher number of cycles. This degradation of the interface region has been monitored by scanning electron microscope analysis.

The reported data are based on experimental investigation.

Studies the treatment of wood‐processing waste using different impregnants as a tool for improving its water‐resistance properties, in order to achieve a reduction in the damage to building elements prepared from the treated wood waste when exposed to weather of relatively high moisture content. Applies different variables such as type of impregnant (synthetic resins or oils), concentration of impregnant, time of impregnation and thermal treatment. Obtains results which show that, generally, using a different concentration of synthetic resins (UF and novolac), or dry oils (motor oil and linseed oil) improved the water‐resistance property of wood waste, and that thermal treatment increases the improvement percentage as a result of impregnation. Also indicates that the optimum improvement in water resistance is attained when using 50 per cent linseed oil as the impregnant for an impregnation time of ten minutes, followed by hardening for three hours at 120°C.

The purposes of this paper are to extend the shelf life of juice/fluids and reduce the thermal damage of their functional components. Thermal processing is a universal method used to extend the shelf lives of juice/fluids. However, combination processing thought to be beneficial in extending the shelf life with least possible thermal damage. The shelf life of the two thermally processed appetizer beverages, i.e. ginger beverage and karpurvalli beverage was established up to six months.

Both appetizer beverages were processed using irradiation in combination with heat treatment. A short thermal treatment at 95°C for 5 minutes was given to the bottled beverages, and these were then irradiated with different dosages of 1, 2 and 3 kGy. The samples were stored at room temperature (18-33°C), as well as at 37°C and periodically analysed for changes in pH, acidity, TSS, browning index, antioxidant activity and gingerol/carvacrol contents and for their microbiological quality.

The results revealed that in both products, the antioxidant activity and the gingerol/carvacrol content reduced, making these microbiologically safe up to eight months. However, combination of irradiation was not found suitable for the appetizer beverages due to more than 50 per cent losses in the functional components.

The combination of thermal and irradiation processing was effective to ensure microbial safety and extend the shelf life of beverages. However, it may not be suitable for preserving all functional properties.

The outcome is result of original work done, and information provided can be a preamble to the researchers targeting improved stability of functional beverages.

The purpose of this paper is to enable the correct selection of the radiofrequency thermal ablation (RFTA) process parameters for an individual patient by applying a computer modelling of RFTA.

The model is based on the X‐ray computer tomography images of the primary and metastatic hepatic tumours. The authors used the professional package of FLUX3D to generate the geometric models, assign materials properties, assign boundary conditions, perform mesh, carry out coupled thermo‐electromagnetic analysis and for post processing. The distribution of temperature and electric potential in the tissues of tumour and liver had been obtained as main results of the calculations.

The computational results show that the RFTA algorithm is effective in solving this practical problem. The computational results show that the selection of the type of electrodes used in the RFTA process is as important as the correct selection of the process parameters, i.e. voltage and frequency.

The paper presents a method to simulate the RFTA process and to select the process parameters.

Supercritical carbon dioxide (sc-CO₂) is a promising novel treatment that might be used in the food industry, such as sc-CO₂ pasteurisation and sc-CO₂ drying. Before sc-CO₂ treated foodstuffs may be introduced to European market, they have to be authorised according to novel food regulation. Therefore, the purpose of this paper is to give an overview of available literature data on sc-CO₂ treated fruits and vegetables, which might be used for novel food authorisation.

The paper is based on literature data available via Science Direct, EBSCO and Wiley concerning sc-CO₂ pasteurisation and drying of fruits/vegetables. Studies performed on animal foodstuffs were manually excluded, while articles related to novel foods and legislation were included in the study.

Database search resulted 34 articles related to microbiological and compositional/nutritional changes in sc-CO₂ treated foods. Obtained data indicated that sc-CO₂ pasteurisation is effective in inactivating microorganisms in liquids, while no general conclusion on the microbiological quality of sc-CO₂ pasteurised solid foods or sc-CO₂ dried foods could be made. Available literature data showed that sc-CO₂ pasteurisation did not result in significant compositional/nutritional changes in liquids, while for sc-CO₂ pasteurised solid foods or sc-CO₂ dried foods, one is not able to make common conclusions due to insufficient research data. Therefore, additional research and case-by-case study for each treated food have to be prepared.

This study is original to the extent that it brought together available information on sc-CO₂ pasteurised and dried foods, needed the novel food application.