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In order to study the effect of the resistance of thermopile on the output performance of thermoelectric microelectromechanical system (MEMS) microwave power sensors, the relationship of the electron mobility and the resistance in n+‐type GaAs is studied, and the reason why the resistance of thermocouple changes with the input microwave power and frequency is analyzed. The experimental results show that in the range of 8 ∼ 12 GHz, the return loss of the sensor is less than −27.75 dB, and the sensitivity of the sensor is 0.055 mV/mW@10 GHz. The resistance of thermopile shows a downward trend with the frequency. With the input power range from 0 to 300 mW, the resistance of thermopile increases from 55.51 to 71.17 kΩ, and it has good linearity. Therefore, this work has a certain reference value for improving the output performance of thermoelectric microwave power sensors.

Being a seasonal fruit mango cannot be cherished over the year; dehydration may be a solution to preserve the deliquesce of mango as mango leather. The processing parameters like puree load (0.4–0.6 g/cm2), total soluble solid (20–30 °B), oven temperature (60–80 °C), and microwave power level (100–300 W) were optimised for a superior textural attribute (hardness) primitive drying method like sun drying, industrially practiced modern methods like hot air oven drying and microwave drying and cutting-edge drying technique like freeze-drying. Response surface methodology and artificial neural network technique were adapted to model these drying procedures by considering the central composite design. The mathematical operations guiding to describe the model were studied. Being an imperative parameter colour quantification is essential for food industries. Current research employs microwave drying to produce mango leather with colour quantification approach. The L, ‘a’ and ‘b’ values of the product have been measured by Hunter Lab colorimeter and by digital image analysis, to determine the chromatic view harmonious to human vision. The relative analysis of colour measurement through these two techniques has been studied.

Energy-efficient CH4-CO2 valorization to fuels and chemicals presents an urgent need considering the great variety of methane sources and the removal of greenhouse gases. In the present work, the microwave-assisted dry reforming of methane, DRM, has been carried out in a custom-designed rectangular mono-mode microwave applicator over several catalyst-support combinations, i.e., Pt/C, Ni/Al2O3, mechanical mixture of Ni/Al2O3-SiC and Ni/SiC. The high and steady conversions of CH4 and CO2 were obtained in the case of the mechanical mixture of Ni/Al2O3-SiC and Ni/SiC. In all the combinations investigated, the conversions reached up to 90% at a WHSV of 11,000 mL/g/h, and microwave power input of 45–60 W, at 800 °C. No significant catalyst deactivation has been observed during the 6-h operation except of Pt/C catalyst. Moreover, the microwave-assisted dry reforming of methane over Ni/SiC was shown to be an interesting, cheap process candidate, able to compete with the steam reforming.

Background Atractylodes chinensis (family Asteraceae) is a perennial herb with many pharmacological effects. Objective Extraction of volatile oil from Atractylodes chinensis was optimized and its hypoglycemic activities were studied. Methods Enzymolysis–microwave-assisted hydrodistillation (EMAHD) was adopted to extract the volatile oil, and the technology was optimized using a single-factor experiment that incorporated response surface methodology (RSM). The extraction rates of volatile oil by EMAHD, microwave-assisted hydrodistillation (MAHD), and hydrodistillation (HD) methods were compared at different times. The ingredients of Atractylodes chinensis volatile oil were analyzed by gas chromatography–mass spectrometry. Scanning electron microscopy (SEM) were used to analyze the microstructural changes in Atractylodes chinensis residue before and after extraction. The inhibition of α-amylase activity was determined. Results The obtained optimal extraction conditions for EMAHD were as follows: enzyme concentration 1.6%, pH 7, enzymolysis time 20 min, enzymolysis temperature 50°C, liquid–solid ratio 30:1, microwave power 455 W, and microwave time 40 min. The levels of the main ingredients and the in vitro inhibition of α-amylase activities were higher for Atractylodes chinensis volatile oil extracted by EMAHD than by HD or MAHD. The powder residue of Atractylodes chinensis remaining after EMAHD showed a ruptured and collapsed cell structure, indicating accelerated dissolution of the volatile oil. Conclusions and Highlights EMAHD is deemed a method with many advantages for extraction of volatile oil from Atractylodes chinensis. The volatile oil of Atractylodes chinensis is a promising component for treating hyperglycemia.

Betacyanin and betaxanthin are natural colouring compounds found in Amaranthus tricolour leaves. Microwave-assisted extraction was performed to extract betacyanin and betaxanthin from the unsalable leaves. A set of different process parameters like microwave power, temperature and time was applied in this study. The combination of 450-W microwave power, 90 °C temperature and 15 min of extraction time resulted in the highest amount of betacyanin (71.95 mg/g of dw) recovery. The highest amount of betaxanthin (42.30 mg/g of dw) was extracted at 200-W microwave power, 60 °C temperature and 15 min of extraction time. Green extraction was done by using water as the solvent based on the solubility of compounds being highest in it. The combined effect of time and temperature was also found to be significant for the extraction. The betacyanin and betaxanthin also exhibited good scavenging ability against superoxide and hydrogen peroxide. The recovery was maximum at higher temperatures with a shorter time of extraction. The SEM images showed that the plant matrix ruptured due to microwaves. The FTIR spectroscopy showed the existence of betacyanin and betaxanthin in the leaf extract. The microwave technique was also proved to be better than ultrasound extraction and Soxhlet extraction. The colour change in the powdered sample was observed after extraction which shows the efficient recovery of pigments. The A. tricolour leaves are the cheaper source of betacyanin and betaxanthin. These compounds not only possess colouring properties but also exhibit antioxidant and medicinal properties. Hence, betacyanin and betaxanthin extracted from these leaves can be used as additives and colourants in food products.

Coconut water (Cococus Nucifera. L) is the clear liquid present inside a coconut liquid endosperm. This water is subjected to microbial contamination and degrades while exposed to ambient air. In general, thermal methods are mostly used in the preservation of liquid foods. In this study, the coconut water was collected from 8-10 months old harvested coconut. Microwave power levels of 540 W, 720 W, and 900 Whavebeen used to treat the coconut water with different exposure times. The treated coconut water was filled in PET bottles and stored at cool temperature (4 °C) and room temperature (27 °C). It is observed that microwave treated 540 W, 720 W, and 900 W coconut water has maintained the quality during the storage period. The physico-chemical properties of microwave-treated coconut water includecolor, pH, TSS, acidity, and reducing sugar on 15days of storage was measured as 13.18 to 15;5.4 to 4.8; 4.5 to 6.0;0.07 to 0.30; and 1.8 to 3.3% respectively.

Wireless power transfer (WPT) has a long history of over 100 years since the first experiment conducted by Nicola Tesla. However, the most interesting innovation of WPT was born in the 21st century. In this decade, near-field WPT commercialization was advanced, and we now use many near-field WPT products, such as wireless chargers for mobile phones and electric vehicles. In the next decade, we can expect the development of far-field WPT via microwaves, through which we can drive Internet of Things (IoT) sensors without batteries based on transmitted or ambient microwave power. We can charge mobile phones with microwave power. When we focus microwave power on a target by beam forming technology, we can transmit higher wireless power to fly drones or from space to the earth. In conjunction with the research & development of microwave-based WPT, radio regulations suitable for each country need to be discussed. In this paper, I review the history, innovation, and status of the radio regulations of WPT via microwaves with the classification of wide-beam WPT, including harvesting, and narrow-beam WPT.

The efficient generation of microwave power has recently gained broad attention in the accelerator community because energy consumption is one of the major concerns for future large-scale high-energy accelerator projects. For the first time, we present a concept of the two-stage multibeam klystron with annular beams (TS MABK). It allows for a remarkably high RF power production efficiency (90%), using a compact design and delivering a cost-effective electro-mechanical solution. The design is for a 1-GHz, 20-MW klystron. The performance of the tube is validated using particle-in-cell computer simulations. In this article, we focus on technological novelties and on mitigation of specific issues.

The present work deals mainly with dehydration characteristics of onion slices. Microwave power levels of 100, 350, 550 and 750 W was practiced to dry onion slices with thicknesses of 2.5, 5, 7.5 and 10 mm. The results showed that moisture diffusivity and specific energy consumption of the process increased with both increasing microwave power and the samples thickness, and ranged from 0.82 × 10−8 to 6.13 × 10−8 m2 s−1 and from 0.82 to 5.43 MJ kg−1 water, respectively. The average activation energy varied in the range of 1.28–1.77. Furthermore, for simulation of drying process and to predict the moisture removal behavior of the samples, multi-layer feed-forward (MLF) artificial neural network (ANN) was employed. Practicing different networks and based on statistical parameters, the best topology, transfer functions and training algorithms were determined. The results revealed that, as a powerful tool, ANN modeling could be effectively used to predict drying kinetics and determine the moisture content of the samples.

The effect of microwave power levels on the drying attributes of Jaya fish ( Aspidoparia jaya) in a microwave dryer was investigated in this study. Microwave power levels of 100, 180, 300, and 450 W were used to dry 50 g of fish samples, and the drying kinetics were evaluated. Higher microwave power levels resulted in faster drying when increased from 100 to 450 W. The moisture ratio of fish during drying was calculated, and the data obtained were applied to 5 well known thin-layer mathematical models of drying, namely Approximate diffusion, Modified Henderson and Pabis, Two-Term, Logarithmic, and Midilli et al. model. Model constants and coefficients were calculated by nonlinear regression techniques. All the models were validated using statistical parameters namely; Coefficient of determination (R2), Root Mean Square Error (RMSE), Chi-square (χ2), and Standard Sum of Error (SSE). The Midilli et al. model gave an excellent fit to the experimental data of all the models evaluated. The effective diffusivity was calculated using Fick’s diffusion equation, and the value varied from 1.40 × 10−9 to 1.08 × 10−8 m2/s. The activation energy and the diffusivity constant were found to be 4.656W/g and 1.22 × 10−8 m2/s, respectively.

Cauliflower is one of the most important winter vegetable crop of india. Dehydrated cauliflower can be used to enhance the taste and nutritional value of various product such as vegetable soup, canned and extruded products etc. Experimental study was conducted to evaluate cauliflower slices using tray drying and microwave power drying techniques. Pretreatment of cauliflower slices as unblanched, blanched and blanched with kms and dried at different temperature (45, 55 and 65°C ) and micro wave at different power level ( 20 W,40 W and 60 W ).The physio-chemical characteristics were evaluated just after preparation of cauliflower slices. Sensory characteristics (colour, flavour, taste, texture and overall acceptability) were evaluated for pre treated cauliflower slices which dehydrated in tray dryer at 45, 55 and 65°C temperature and in microwave power dryer at 20, 40 and 60 W power. Sensory evolution was done using hedonic rating test method to measure the consumer acceptability. Results showed that highest score was obtained as 7.9 for colour at 65°c in KMS balanced condition where as highest score for taste was obtained as 7.9 at 65°C in balanced condition in tray dryer. The maximum value of flavour (8.0) was obtained at 65°C in blanched condition where as highest value of texture (7.9) at 65°C in blanched condition in tray dryer in microwave dryer, the highest values of colour (7.9) was obtained at 60W in kms blanched condition where as highest value of taste (7.9) at 60 W in unblanched conditions. The highest score of flavour (8.1) and texture (7.9) were found at 60 W in kms blanched condition in microwave power drying. Overall acceptability score was highest (7.92) in microwave power drying than tray drying (7.85) in kms blanched sample at 60 W power and 65°C temperature drying, respectively. Microwave power drying was found most suitable for kms blanched cauliflower slices at 60 W power level.

Bu çalışmada, sıcak hava ile kurutma (50, 60, 70 °C ve 1.8 m/s), mikrodalga kurutma (180, 360, 540 W) ve dondurarak kurutma (0.2, 0.15, 0.1 mbar) olmak üzere üç farklı kuruma yöntemi deneysel olarak incelenmiş ve yağı azaltılmış beyaz peynirin (RFWC) kurutma kinetiği belirlenmiştir. Mikrodalga kurutma yönteminde işlem süresi, RFWC için sıcak havayla kurutma ve dondurarak kurutma yöntemlerinden önemli ölçüde daha kısadır. RFWC'nin kuruma kinetiğini temsil eden en yüksek R2 ve en düşük RMSE ve χ2 değerlerini hedefleyen en uygun kurutma modelini belirlemek için yarı deneysel modeller uygulanmıştır. Farklı kurutma yöntemleri için efektif difüzyon katsayısı değerleri 1.521 x 10-9 ile 4.432 x 10-8 m2/s arasında değişmiştir. Sıcaklık, mikrodalga gücü ve vakum basıncının artırılmasıyla efektif difüzyon katsayısı değerleri artmıştır. Aktivasyon enerjisi değerleri sıcak havayla kurutma için 12.421 kJ/mol ve mikrodalga kurutma için 5.599 W/ g olarak belirlenmiştir., In the current study, three different drying methods, including hot air drying (50, 60, 70 °C and 1.8 m/s), microwave drying (180, 360, 540 W) and freeze-drying (0.2, 0.15, 0.1 mbar) were experimentally studied and the drying kinetics of reduced-fat white cheese (RFWC) were determined. Microwave drying process time was significantly shorter than hot air drying and freeze-drying for RFWC. Semi-empirical models were applied to determine the most appropriate drying model targeting the highest R2 and the lowest RMSE and χ2 values representing the drying kinetics of RFWC. The effective diffusion coefficient values for different drying methods varied from 1.521 x 10-9 to 4.432 x 10-8 m2/s. Through increasing the temperature, microwave power, and vacuum pressure, effective diffusion coefficient values increased. The activation energy values were determined as 12.421 kJ/mol for hot air drying and 5.599 W/g for microwave drying.

When choosing a method for drying rapeseed seeds, along with the productivity and energy costs of the process, it is necessary to take into account the quality of the resulting product. It is determined by the appearance of seeds, the balance of protein, vitamin and amino acid composition, as well as the quality of the oil contained in the seeds. Therefore, it is necessary that during the drying process, these indicators should be preserved and, if possible, improved.The aim of this work is to compare the quality indicators of rapeseed seeds dried in a microwave device with a swirling flow of heat carrier and the traditional method of convective heat transfer.The qualitative indicators of rapeseed and canola oil during convective and microwave drying were studied. The influence of microwave energy on the drying process and the quality of rapeseed in a microwave device with a swirling coolant flow was studied. Organoleptic and physico-chemical indicators of the quality of rapeseed dried by convective method and using a combined microwave power supply were determined. The study of the composition of proteins, the content of amino acids and vitamins of group E, as the most important quality indicators in the production of food products and feed additives using rapeseed. A comparative analysis of changes in the quality indicators of rapeseed seeds is performed, which allows identifying structural changes occurring during the drying process and assessing the quality of the resulting product during convective drying and using a combined microwave power supply. In the experimental studies found that the use of microwave energy in the drying process leads not only to increasing productivity, reducing energy costs, but also helps to preserve nutritional value, complete protein, amino acids and vitamin E dried product.

In the present work, microwave energy was used for casting Al 7039 alloy at 2.45 GHz in the ambient cavity environment. Effects of input power and insulation of the mould assembly during irradiatio...

Orange production in 2020 projected to reach more than 3.2 million tons, with an estimated growth of 4.93% per year. As a result, large amounts of orange peel are available as a by-product and are treated as waste, creating environmental problems. This problem can be turned into potential if essential oils can be extracted from orange peels. The purpose of this study is to compare the methods of Microwave Hydrodiffusion and Gravity (MHG) and Microwave Steam Diffusion (MSDf) in terms of extraction time velocity, yield, electricity consumption, environmental impact (CO2 gas emissions) and their chemical composition. In this study, 300 grams of fresh orange peel (Citrus aurantium L) used with three microwave power variations: 136 watt, 264 watt, and 440 watt and extraction time of 15 minutes, 30 minutes, 45 minutes, and 60 minutes. The MSDf method produces yields faster than the MHG method at an optimal power of 264 W. In the 20th minute, the MSDf method produces an essential oil yield of 1.95%, while the MHG method produces 1.93% yield at the 40th minute. The MSDf method provides the number of oxygenated compounds (1.4%) is higher than the MHG method (1.12%). This study shows that the MSDf method can produce better quality oils as like as the MHG method. Based on the electricity consumed ratio, the MSDf method is 50% more energy-efficient than the MHG method. Emissions of CO2 gas released into the air in the MSDf method (0.07 kg) are also less than MHG (0.14 kg), so the impact on the environment is not too significant.

The current experiment was under taken to dry best quality coriander leaves using microwave drying. The response surface methodology was used to design and optimize the experimental treatment. The dried coriander leaves were analysed to obtain the changes in response of dependent variables of sensory attribute viz., colour, aroma, texture and overall acceptability due to varying the independent variables especially the microwave power level and drying time. The process variable for drying of coriander leaves optimized as microwave power level (70%) and drying time (7 min and 23 s). According to the optimized process variables, the validated responses were recorded as moisture content 2.05%, colour value of 8.35, aroma value of 7.28, texture value of 8.34 and overall acceptability of 7.57. The drying of coriander leaves using continuous microwave dryer is the best to get best quality dried coriander leaves with maximum retention of sensory attribute.

In the study, essential oil extraction from turmeric was carried out using modified microwave distillation system and rotary evaporator unit. In present study, effect of input parameters i.e. microwave power (200, 250, 300, 350 and 400 W) and extraction time (10, 15, 20, 25 and 30 min.) on physical properties (oil yield, specific gravity, refractive index and colour) of essential oil were studied. Fixed ratio samples (1:1:1) i.e. turmeric powder, solvent and distilled water was used during the experiment conducted. Essential oil yield using hexane varied from 1.895% to 4.973% while from 0.180% to 1.226% using petroleum ether solvents. Quality parameters varied i.e. specific gravity from 0.910 to 0.923, refractive index from1.478 to 1.506, colour values for oil ranges L* from 70.60 to 98.60, a* from –25.60 to 15.1 and b* from 82.1 to 88.5. Optimum values of process parameters for maximum oil recovery (4.973%) and best quality of oil (specific gravity: 0.915; refractive index: 1.485) was found at microwave power 300 W and extraction time 20 min.

Effects of microwave power on the sensory properties (taste and aroma), chemical composition (catechins, caffeine, crude protein, and amino acid), active composition (flavones, triterpene, polysaccharide, and ergosterol) and antioxidant properties (superoxide free radical and hydroxyl radical scavenging abilities, reducing power) of Ganoderma lucidum fermented sea-buckthorn tea were investigated. G. lucidum fermented sea-buckthorn tea was dehydrated using microwaves at three power settings: 125, 250, and 500. After microwave treatment, a statistically significant difference in the chemical composition, active composition and antioxidant capacity (p

Crystal seedless guava is a new horticultural commodity that is cultivated in Indonesia and has many benefits. Crystal seedless guava has the potential of essential oil to be extracted from the leaves. Extraction using the microwave hydrodistillation method is an alternative to improve the efficiency and effectiveness of the essential oil extraction process. The purpose of this study was to determine the effect of microwave power and the feed to solvent ratio toward the characteristics of density and refractive index of essential oil from crystal seedless guava leaves. The reduced size crystal seedless guava leaves were extracted by microwave using aquadest as solvents with the feed to leaves. The ratio of feed to solvents used in this study was 1:4, 1:5, 1:6, and 1:7 (weight/volume or w/v). The second variables were performed using various microwave powers of 300, 450, and 600 Watts. The extraction conditions were carried out at ± 100 o C at one atmospheric pressure for three hours. The results showed that microwave powers and material to solvent ratios had significantly effect toward the density of essential oil from crystal seedless guava leaves. However, the variables had no significant difference in the value of the refractive index. The higher number of microwave powers and the solvent to feed ratios had a higher number of density. The highest density and refractive indexes were 0.948 grams/ml and 1,49862, respectively. The best extraction condition to extract the essential oil from crystal seedless guava leaves using microwave hydrodistillation was performed by microwave power of 600 Watt with 1:7 (w:v) as leaves to solvent ratio.

The main focus of this study was to develop and calibrate a computerized image analysis system in order to measure the color of banana (Musa Cavendish) under microwave treatment. Bananas were cut into 2 mm slice thickness and dried at two different microwave power level; 540 W and 180 W. An algorithmic was developed which converted RGB color value from a color image into CIE L*a*b* values very well (Error(L*) = 2.163%, Error(a*) = 4.458%, Error(b*) = 5.224%). Once the calibration is completed, it was applied to measure the color change in the banana slice during drying. The value of L* decreased from 89.01 to 71.17 and from 82.60 to 72.53 for both microwave treated samples suggesting browning is taking place during the drying operation. The value of a* increased from − 0.80 to 11.50 and from − 3.90 to 5.18 for 540 and 180 W microwave treated banana slices respectively suggesting tendency of redness increased. The same type of increment was observed for b* value. It changed from 36.46 to 60.51 and 34.02 to 72.82 for 540 and 180 W microwave treated banana slices, respectively. Artificial Neural Network (ANN) modeling was used for prediction of the developed CVS’s values.

Microwave cladding is an emerging surface modification technique. Temperature control is the key issue in any surface modification technique. In microwave cladding, non-contact temperature measurement methods are widely used; however, these methods report only the surface temperature of the susceptor. In the present study, a modified B-type thermocouple was used to measure the real time-temperature distribution while developing Ni-based clad. Formation of clad has been discussed with respect of time-temperature distribution. Effect of microwave power on heating profile was also investigated.

The objective of this research is to study the correlation between response surface methodology (RSM) and artificial neural network (ANN) on the antioxidant activity and phenolic compound extracted from unripe Musa acuminata peel waste by microwave-assisted extraction (MAE). Distilled water was used as a substitute for organic solvents throughout the extraction process to obtain toxic-free polar bioactive compounds. DPPH free radical assay and Folin–Ciocalteu methods were used to measure the antioxidant activity and the total phenolic compounds (TPC), respectively. The optimal conditions were obtained at 650 W of microwave power, 110 s of extraction time, and 0.06 g/ml of solid-to-solvent ratio. The optimized MAE extraction yielded 76.81% and 418.46 mg GA/100 g extract of antioxidants and TPC, respectively. Overall, the solid-to-solvent ratio is the most significant variable, followed by the extraction time. Both the RSM and ANN models have delivered good quality prediction for antioxidants and TPC. Nonetheless, the ANN model showed higher predictive potential due to its higher coefficient of determination (R2ANNantioxidant = 0.9803, R2RSMantioxidant = 0.9742), lower root-mean-square error (RMSEANNantioxidant = 2.69, RMSERSMantioxidant = 3.07), and lower absolute average deviation (AADANNantioxidant = 3.38%, AADRSMantioxidant = 5.64%) for both the antioxidants and the TPC. The incorporation of ANN into the RSM model in this study has successfully countered the drawbacks of RSM.

The influence of intermittent-microwave drying and hot-air drying on drying characteristics and rehydration properties of apple slices were compared. Microwave powers have crucially affected the drying rate, effective moisture diffusivity and drying time. As microwave power increased, the drying rate and effective moisture diffusivity increased while the drying time reduced. In intermittent-microwave drying, the effective moisture diffusivities were estimated between 4.47 × 10-9 and 2.54 × 10-8 m2 s-1. Longer drying time, slower drying rate and less effective moisture diffusivity were obtained from hot-air drying when compared to intermittent-microwave drying. Higher temperatures provided higher drying rate and effective moisture diffusivity. Effective moisture diffusivities of hot-air dried-apple slices were calculated in the range of 3.38 × 10-10–6.25 × 10-10 m2 s-1. Moreover, Page model gave the best fitting to intermittent-microwave drying curves, while hot-air drying curves were suitably described by Parabolic Model. On the other hand, the rehydration ratio of intermittent-microwave dried-apple slices was higher than hot-air dried-apple slices. Additionally, Peleg model was defined to be the best model predicting experimental rehydration data in both drying techniques. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.

Microwave-assisted extraction (MAE) and solvent-free microwave extraction and Soxhlet extraction were applied to Ray Ruby grapefruit leaves (Citrus paradisi Macf.) to compare extract efficiency. Face centered composite designs were constructed via response surface methodology. Effects of factors of MAE were investigated on total phenolic content (TPC) and naringin content (NC). The optimized conditions were established as 1.4 kWL−1 for microwave power density, 20.00 gL−1 for solid/solvent ratio, 218.180 s for extraction time, while responses were calculated as 14.210 mg of gallic acid equivalent per g of the dried leaf (mg GAE g−1DL) and 13.198 mg of naringin per g of dried leaf (mg Ng−1DL) for TPC and NC, respectively. SFME and classical Soxhlet methods were also conducted for comparison reasons.

The paper proposes a methodology for designing bridge devices designed for dividing and summing power in the microwave range.

The current loading of an accelerated electron beam in the accelerating fields of a LUE-200 linear accelerator of the IREN facility at the Joint Institute of Nuclear Research (Dubna) is discussed. The LUE-200 accelerator consists of two accelerating sections operating on a traveling wave at a frequency of 2856 MHz with the microwave power compression systems of the SLED type. The limits of the accelerated beam current values are determined for various pulse durations of the beam current and microwave power levels fed into the accelerating sections. The calculation results are compared with the measured data.

The present study deals with the optimization of phenolic compounds extraction from artichoke (Cynara scolymus L.) waste, and development of a functional enriched edible oil with potential health promoting effects.. Box–Behnken Design (BBD), a widely used form of response surface methodology (RSM), was applied to investigate the effect of process variables on the microwave-assisted extraction (MAE) for the recovery of total phenolic compounds (TPC). Independent variables including ethanol concentration (%), microwave power (W), irradiation time (min), solvent-to-material ratio (mL/g) for MAE were studied. The statistical analysis revealed that the optimal MAE conditions were obtained with 72 % ethanol as extraction solvent, 81:1 mL/g of solvent/solid ratio, 4 min and 900 W for irradiation time and power, respectively. Maximum predicted TPC recovery under the optimized conditions was 37.43 ± 1.26 mg GAE/g DW, which was close to the experimental value 36.10 ± 0.72, indicating suitability of the employed model and the success of RSM in optimizing the extraction conditions. The TPC confirmed the efficiency of MAE methods when compared with the conventional method. The studied edible oil enriched with the optimized extract had a content of phenolic compounds equivalent to 56.41 ± 2.03 μg/mL compared to the control oil.

In this study, microwave drying characteristics of black mulberry were studied at microwave power levels of 90, 180 and 360 W. Obtained experimental drying results were applied to seven mathematica...