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Microwave curing (MC) can facilitate rapid concrete repair in cold climates without using conventional accelerated curing technologies which are environmentally unsustainable. Accelerated curing of concrete under MC can contribute to the decarbonisation of the environment and provide economies in construction in several ways such as reducing construction time, energy efficiency, lower cement content, lower carbonation risk and reducing emissions from equipment.

The paper investigates moisture loss and pore properties of six cement-based proprietary concrete repair materials subjected to MC. The impact of MC on these properties is critically important for its successful implementation in practice and current literature lacks this information. Specimens were microwave cured for 40–45 min to surface temperatures between 39.9 and 44.1 °C. The fast-setting repair material was microwave cured for 15 min to 40.7 °C. MC causes a higher water loss which shows the importance of preventing drying during MC and the following 24 h.

Portland cement-based normal density repair mortars, including materials incorporating pfa and polymer latex, benefit from the thermal effect of MC on hydration, resulting in up to 24% reduction in porosity relative to normal curing. Low density and flowing repair materials suffer an increase in porosity up to 16% due to MC. The moisture loss at the end of MC and after 24h is related to the mix water content and porosity, respectively.

The research on the application of MC for rapid repair of concrete is original. The research was funded by the European commission following a very rigorous and competitive review process which ensured its originality. Original data on the parameters of porosity and moisture loss under MC are provided for different generic cementitious repair materials which have not been studied before. Application of MC to concrete construction especially in cold climates will provide environmental, economic and energy benefits.

This paper aims to investigate the effect of hydrothermal treatment by conventional, microwave and pressure cooking on the cooking properties, proximate composition and organoleptic characteristics of dehulled Moringa oleifera seeds.

Samples of Moringa oleifera seeds were subjected to cooking for the minimum time by each of the methods under study. Cooking properties, proximate composition and organoleptic characteristics were determined following standard analytical procedures.

The results showed that the average cooking time were 25, 30 and 40 mins for conventionally, pressure- and microwave-cooked moringa kernels, respectively. There was no significant difference in cooking weight, moisture absorbed and water uptake ratio of conventionally and pressure-cooked samples. The protein content of moringa kernel reduced from 41.9 for raw kernels to 40.2, 41.2 and 36.9 per cent for conventionally, pressure- and microwave-cooked samples, respectively. Pressure and microwave cooking indicated 40.1 and 39.3 g/100g of crude fat, whereas raw kernels indicated 37.1 g/100g. Conventionally and pressure-cooked kernels had lower fibre content than the raw kernels, but there was no significant difference in the ash contents of the samples. Cooking influenced the proximate composition and colour of moringa kernels. Microwave cooking indicated higher values of cookability than other cooking methods considered in this study, but no significant difference was observed in the organoleptic characteristics of moringa kernels due to the cooking methods.

Given the high protein and vital nutrients content which are seldom found in daily diets, moringa kernels may be considered by processors of edible nuts and kernels for food-based applications such as cooked, roasted, mixed or spiced kernels.

This work is perhaps the first to document moringa seeds processing by hydrothermal treatment.

The dyeing of cotton and cotton/wool blend fabric by using reactive dyes has been studied with both conventional heating and microwave irradiation. The effects of the dye bath pH, microwave power, dyeing time and dye concentration are studied and the resulting shades obtained by dyeing through microwave and conventional techniques are compared. The results of the dyed samples indicate that microwave irradiation is more effective than conventional heating. Color strength values obtained are found to be higher by microwave irradiation. The results of the fastness properties of the dyed fabric are good to very good. The dyeing kinetics of cotton and cotton/wool blend fabrics are also compared by using the two methods. The values of the dyeing rate constant, half dyeing time (t _1/2), stander affinity and microwave efficiency are calculated and discussed. The physical properties of the samples are studied before and after exposure to microwave irradiation by a scanning electron microscope and an x- ray analysis.

The aim of this work was to study the effect of the different levels of salt and the temperature on some physico-chemical and colour change properties of microwave-dried beef round (M. semitendinosus).

The samples were pretreated with different temperatures (0°C, 40°C and 50°C) and salting (0, 1.5, 2.5%). Later these samples have been dried by the microwave energy at 540 W for seven minutes. Some physical properties (water activity, moisture content, change in diameter, change in thickness, change in shrinkage ratio) and texture, colour and microscopic surface structure analysis were conducted in dried beef round samples.

As a result, the colour and moisture were the most affected factors. Also, physical and microstructural characteristics were affected by salting and pre-drying. In addition, while the textural structure did not show a significant difference, meat weight and water activity varied.

Meat obtained from a local butcher in Konya was used as the study material. In addition, only a special part of the meat (M. semitendinosus) was used in the study. In the drying process, the parameters were determined as 540 W and 7 min. These are the limitations of the research.

All changes that can occur in the physical properties of the meat after the drying process were examined. The structure of beef round samples formed by microwave drying was shown by using electron microscope. The effects of pretreatment such as salting and pre-drying have been examined on microwave drying.

This paper aims to discuss the general principles behind the microwave sensing and demonstrates the potential of cavity microwave resonator device in real-time monitoring for: environmental monitoring with the focus on wastewater pollution, a system for oil/gas/water content evaluation in a dynamic pipeline, a system for real-time determination of bacteria concentration and a method for non-invasive glucose determination.

Microwave sensing is a rapidly developing technology which has been successfully used for various industrial applications including water level measurements, material moisture content, in construction industry for non-invasive evaluation of structures and even in the healthcare industry for non-invasive real-time monitoring of glucose in diabetic patients. Novel microwave cavities designed and tested for specific applications are presented.

The paper provides experimental results of testing the novel microwave sensing systems in a range of industrial and healthcare applications and discusses the potential of these systems for real-time monitoring of processes and parameters.

The concept of real-time microwave sensing was successfully tested, but further experiments are required to account for possible interference mechanisms before it can be used commercially on a large-scale.

It is suggested that a novel approach to wastewater monitoring, namely using specially designed microwave cavity sensors, could lead to a successful development of an advanced platform capable of providing for a real-time detection of water content with superior sensitivity. Also, a system for real-time multiphase fluid composition monitoring is reported, which is essential for sustainable oil industry operation.

The paper illustrated the potential of microwave sensing as a real-time monitoring platform for a broad spectrum of commercial applications, with a focus on system developed by the authors, namely, for the monitoring of a multiphase fluid flow in a dynamic oil pipeline, for real-time monitoring of nutrients concentration in wastewater and for healthcare industry, in particular for real-time non-invasive determination of the glucose levels and bacteria concentration.

This paper aims to investigate the morphology and tensile properties of SAC305 solder alloy under the influence of microwave hybrid heating (MHH) for soldering at different microwave parameters.

Si wafer was used as susceptor in MHH for solder reflow. Microwave operating power for medium and high ranging from 40 to 140 s reflow time was used to investigate their effect on the microstructure and strength of SAC305/Cu solder joints. The morphology and elemental composition of the intermetallic compound (IMC) joint were evaluated on the top surface and cross-sectional view.

IMC formation transformed from scallop-like to elongated scallop-like structure for medium operating power and scallop-like to planar-like structure for high operating power when exposed to longer reflow time. Compositional and phase analysis confirmed that the observed IMCs consist of Cu₆Sn₅, Cu₃Sn and Ag₃Sn. A thinner IMC layer was formed at medium operating power, 80 s (2.4 µm), and high operating power, 40 s (2.5 µm). The ultimate tensile strength at high operating power, 40 s (45.5 MPa), was 44.9% greater than that at medium operating power, 80 s (31.4 MPa).

Microwave parameters with the influence of Si wafer in MHH in soldering have been developed and optimized. A microwave temperature profile was established to select the appropriate parameter for solder reflow. For this MHH soldering method, the higher operating power and shorter reflow time are preferable.

This paper aims to study the structural, electrical and microwave properties of (Sr_0.6Ca_0.4) (Co_yMn_1−y) O₃ (0.2 ≤ y ≤ 1.0) thick-film ceramics.

The thick films of (Sr_0.6Ca_0.4) (Co_yMn_1−y) O₃ (0.2 ≤ y ≤ 1.0) on the alumina substrate have been delineated using screen printing technique. The structural analysis was carried out using an X-ray diffraction method and scanning electron microscopy. The direct current (DC) electrical resistivity is measured using a two-probe method. Microwave absorption was studied in the 8-18 GHz frequency range by using the Waveguide Reflectometer Method. The permittivity and permeability in the 8-18 GHz frequency range were measured by using Voltage Standing Wave Ratio slotted section method.

The thick films have orthorhombic perovskite structure with dominant (020) plane. By using first-principle calculation method, theoretical and experimental lattice parameter and cell volume of (Sr_0.6Ca_0.4) (Co_yMn_1−y) O₃ are matched with each other. The cobalt content changes the morphology from plates to needles. The DC electrical resistivity increases with increase in Co content and decreases with increase in temperature. (Sr_0.6Ca_0.4) (Co_yMn_1−y) O₃ thick film shows 75 per cent microwave absorption both in the X band and Ku band. The microwave permittivity and permeability decreases with increase in frequency and Co content.

Structural, electrical and microwave properties of (Sr_0.6Ca_0.4) (Co_yMn_1−y) O₃ (0.2 ≤ y ≤ 1.0). Thick film ceramics on alumina substrate is reported for the first time.

In this study, the purpose has been to investigate a novel pathway for the synthesis of high performance diketopyrrolopyrrole pigments (DPPs) using diethyl succinate under microwave irradiation in the presence of ionic liquid (1‐butyl‐3‐methylimidazolium tetrafluoroborate, [BMIM][BF₄]), as a novel medium.

Rapid synthesis of DPPs was achieved in [BMIM][BF₄] as well as in dry medium under microwave irradiation based on succinate ester condensation with benzonitrile derivatives. The obtained results were compared with those of conventional method as well as Reformatsky route under microwave irradiation. The obtained pigments were characterized and their optical properties and the morphologies were investigated.

This study provides a novel approach to the synthesis of DPP pigments in a flash time with comparatively good yields.

DPPs have been synthesized via succinate ester route in ionic liquid media. Besides, they can also be synthesized based on Reformatsky method in ionic liquid media.

The developed method provides a simple and practical solution to improving the rapid synthesis of DPP pigments, with regard to their traditional application in many different industries, such as paints, inks, and plastics, as well as in electronic devices, LEDs, and laser dyes.

The method for synthesis of DPP pigments via succinate ester route in ionic liquid under microwave irradiation in a flash time was novel and could find applications in DPP pigments' industries.

This work was undertaken to evaluate the impact of different drying methods (convective, microwave and freeze drying) on color, selected secondary metabolites (total phenolic substances, ascorbic acid, beta-carotene and antioxidant capacity), texture (hardness), sensory properties and microstructure of carrot slices.

Convective drying at three different temperatures (55, 65 and 75 °C), microwave drying at two different power levels (100 and 200 W) and freeze drying were applied.

Significant differences were found among fresh and dried-carrot slices. Convective-dried carrots showed better quality characteristics in comparison with microwave-dried carrots. The convective-dried carrots at 65 °C exhibited the highest retention of bioactive compounds and best color among all convective drying conditions. The microwave-dried carrot slices at lower power (100 W) showed higher quality characteristics compared to the dried carrots at 200 W. The freeze-dried carrots exhibited the highest retention of secondary metabolites, sensory properties and best color among all drying methods.

The results from this study are significant for the processing of dried carrots by optimizing the conditions to obtain a high-quality product. Overall, freeze drying is a promising application as shown in the present study by its capability to better retention carrot quality underlying color, sensory, texture, microstructure and secondary metabolites.

This paper aims to investigate in a self-designed closed loop reactor process conditions for thermal inactivation of B16 melanoma cells by microwave and conventional heating.

Besides control experiments (37°C), inactivation rate was determined in the range from 42°C to 46°C. Heating was achieved either by microwave radiation at 2.45 GHz or by warm water. To distinguish viable from dead cells, AnnexinV staining method was used and supported by field effect scanning electron microscopy (FE-SEM) imaging. Furthermore, numerical simulations were done to get a closer look into both heating devices. To investigate the thermal influence on cell inactivation and the differences between heating methods, a reaction kinetics approach was added as well.

Control experiments and heating at 42°C resulted in low inactivation rates. Inactivation rate at 44°C remained below 12% under conventional, whereas it increased to >70% under microwave heating. At 46°C, inactivation rate attained 68% under conventional heating; meanwhile, even 88% were determined under microwave heating. FE-SEM images showed a porous membrane structure under microwave heating in contrast to mostly intact conventional heated cells. Numerical simulations of both heating devices and a macroscopic Arrhenius approach could not sufficiently explain the observed differences in inactivation.

A combination of thermal and electrical effects owing to microwave heating results in higher inactivation rates than conventional heating achieves. Nevertheless, it was not possible to determine the exact mechanisms of inactivation under microwave radiation.