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Summary: Total carotenoid amounts of rocket samples were established between 120.56 μg g−1 (fresh) and 130.06 μg g−1 (microwave). In addition, total phenol and flavonoid results of rockets dried in microwave and oven were found between 655.53 (oven) and 1790.96 mg GAE/100 g (fresh) to 254.03 (oven) and 1668.83 mg/100 g (fresh), respectively. Also, radical scavenging activities (DPPH and FRAP) of rocket samples were measured between 7.55 (oven) and 25.45 mmol kg−1 (fresh) to 35.59 (oven) and 66.74 mg g−1 (fresh), respectively. Gallic acid, 3,4‐dihydroxybenzoic acid, catechin and rutin were the main phenolic compounds found in rocket samples. Catechin contents of rockets dried in microwave and oven systems were recorded between 349.60 (oven) and 442.47 mg/100 g (fresh). Gallic acid and 3,4‐dihydroxybenzoic acid amounts of rocket samples were monitored between 52.84 (oven) and 952.15 mg/100 g (fresh) to 30.92 (oven) and 282.15 mg/100 g (fresh), respectively. The protein amounts of rockets were determined between 11.00% (microwave) and 11.60% (oven). P and K values of fresh and dried rockets were found between 3148.36 (oven) and 3752.33 mg kg−1 (fresh) to 39 363.75 (microwave) and 36 883.41 mg/kg (fw), respectively. Also, Ca and Mg results of fresh and dried‐rockets were found between 26 739.33 (microwave) and 29 534.48 mg kg−1 (fresh) to 3125.32 (microwave) and 3431.70 mg kg−1 (fresh), respectively. The highest S (14 665.30 mg kg−1) was detected in rocket sample dried in microwave. [ABSTRACT FROM AUTHOR]

Summary: This study compared the furan levels and physicochemical properties of various 70 samples of five nuts (peanuts, almonds, cashew nuts, hazelnuts, and sacha inchi) roasted using an air fryer (AF) and microwave oven (MO). In the five nuts, furan levels ranged from 1.11 to 2.39 ng g−1 before roasting. As the AF‐based and MO‐based roasting progressed, the furan levels increased to 6.39–165.52 ng g−1 and 11.47–183.87 ng g−1, respectively. The contents of polyunsaturated fatty acids (linoleic acid and linolenic acid) decreased significantly after roasting but the content of monounsaturated fatty acid (oleic acid) showed only slightly significant differences between the control and roasted nuts. The total phenolic content and antioxidant activity increased by up to 337% and 218% as roasting progressed but decreased slightly when roasting was performed at 180 °C for 20 min in an AF or at 700 or 1000 W for 5 min in an MO. This study provides useful information on furan production and the changes in physicochemical properties such as fatty acid composition, colour, BI, TPC, and antioxidant activity of nuts roasted using an AF or MO. [ABSTRACT FROM AUTHOR]

Summary: In this study, the changes in bioactive properties, phenolic compound profile and mineral results of fresh, boiled and dried pea seeds were investigated. It was observed that the total phenol, flavonoid and antioxidant capacity results of heat‐treated peas were decreased when compared to the control. Total carotenoid result of peas dried in oven and microwave were significantly increased compared to control and boiled peas (P < 0.05). Oven or microwave heating treatments increased the L* values of samples, while boiling caused a decrease in L* results. As with the bioactive properties of peas, the phenolic component amounts of peas were also low in the dried samples, and a linear correlation was obtained between the phenolic components and bioactive properties of the treated pea seeds. The highest protein content was detected in the peas dried in the conventional heater. Both fresh and dried peas are rich in K, P, Ca, Mg, S, Fe and Zn. K results of fresh and dried pea samples ranged from 19 258.50 (boiling) to 23 820.31 ppm (dw; oven). [ABSTRACT FROM AUTHOR]

In this study, the effects of microwave (540, 720 and 900 W) and oven (120, 150 and 230°C) roasting techniques on the total phenolics, flavonoids, antioxidant capacity, polyphenolic and fatty acid results of sunflower seed and oils were investigated. Total phenol (except oven 150°C), flavonoid (except oven 120°C) contents and antioxidant activity values of sunflower seeds and oils subjected to oven and microwave heat treatment decreased compared to the control. Total phenolic, total flavonoids and antioxidant activities were higher in MRS oil than ORS oil. Individual phenolic constituent in both seed and oil samples from ORS and MRS showed significant (p < 0.05) changes to the control (non‐roasted seed and its oil). A general increase in the phenolic components of seeds and oils was observed with oven and microwave roasting compared to the control. Oleic acid values (%) of the oil extracted from seeds roasted in oven and microwave systems were recorded to be between 23.76 (120°C) and 29.41% (150°C) to 24.32 (540 W) and 26.10% (720 W), respectively. Linoleic acid values of the oils obtained from seeds roasted in oven and microwave systems varied to be between 57.01 (150°C) and 65.89% (120°C) to 60.70 (720 W) and 65.26% (540 W), respectively. As a result of the applied heat treatment, while the linoleic acid values of the oil samples decreased, an increase was observed in the palmitic, stearic and oleic acid values of the oil. [ABSTRACT FROM AUTHOR]

The power output of five recent domestic microwave ovens (on the market 2003/2004) was measured using a standard 1000 g water load during 30 min of continuous use. The power output of the ovens declined significantly ( P ≤ 0.05) in the first 5 min of use, ranging from a minimum of 7.0% to a maximum of 19.7%. Further but not always significant declines ( P ≤ 0.05) were measured after 20 min of continuous use. No significant reductions were measured between 20 and 30 min. Overall, the mean reduction in power output after 30 min of continuous use was 17.3% for these five ovens compared with 13.5% for five ovens in a previous study. Based on trials carried out approximately a decade apart, there has not been any improvement in the performance of domestic microwave ovens in terms of the decline in power output after continuous or prolonged use. The authors believe that many users, including consumers, caterers and those using domestic microwave ovens for research purposes, would benefit from a greater awareness and understanding of how the rapid reduction in power output in the first 5–20 min of use is likely to affect the expected heating performance. [ABSTRACT FROM AUTHOR]

A test procedure has been developed and used to characterise the performance of domestic microwave ovens in relation to the heating of chilled ready meals. The procedure uses reproducible test loads, which simulate the heating and weight loss characteristics of a chilled ready meal under consumer use. The temperature distribution after heating from 5 °C to a defined minimum temperature of 70 °C is measured in the food simulant using a purpose designed multipoint thermocouple ‘hedgehog’ probe. The temperature, weight loss and heating time data from the test are entered into a spreadsheet analysis program, which provides a simple oven performance ‘score’ and/or comprehensive heating performance data. [ABSTRACT FROM AUTHOR]

Summary There is a need for standard methods of testing domestic microwave ovens that relate to their reheating performance with chilled convenience meals. The investigations reported here have produced a simple procedure for comparing the three most important reheating characteristics of a domestic microwave oven: its ‘true’ power; heating variability; and repeatability. The tests are relatively simple to do, and require only a few additional items of equipment to those that a laboratory performing existing output power tests would already possess. Three identical tests are required: one with a liquid test material, one with a solid and one with a combination of the two components. One additional stage is done with the liquid test material. The data produced can be reduced to three numbers, which are measures of the true power, variability and repeatability of the oven. A further simple analysis, which weights the relative importance of each factor to the consumer, would produce a single value for the oven's relative reheating performance. Ovens with unusual or extreme performance characteristics can therefore be identified easily. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effect of different reheating methods and conditions on the proximate composition, mineral content, oil quality, and functional and microbiological properties of cow meat. For this, a survey was carried out to identify the reheating methods used in the community. For this study, 8.6 kg of raw beef was used and group 1 (500 g) served as raw control. The remaining 8.1 kg was boiled for 30 min in 5 L of water. Four hundred grams of boiled beef was removed and served as cooked control (group 2). The remaining 3688 g was divided into four groups of 922 g, which were, respectively, divided into subgroups of 307 g. The four sets of subgroups were, respectively, reheated by boiling, frying, microwaving and oven roasting for 3 days. Reheating was done three times a day and samples were collected at the end of each day for further analysis. Changes in proximate composition, mineral content, oil quality, functional properties, and microbiological count were evaluated using standard methods. Results showed that frequent reheating of food was the most used preservation method of cooked food, and boiling and steaming were the most used methods. Reheating time significantly reduces the protein, mineral content, and oil quality of cow meat in general. For the functional properties, reheating methods/conditions generally increased the water‐holding capacity, loose and packed bulk densities as well the pH of the meat. Reheating by frying increased the porosity and Hausner ratio of the meat powder while all the reheating treatments reduced the swelling capacity and titratable acidity of cow meat powder. Generally, the reheating methods and duration significantly reduced the bacterial count of cow meat powder. Cow meat should not be reheated for more than 2 days in order to preserve its physiochemical properties. [ABSTRACT FROM AUTHOR]

Summary: In present investigation, the effect of roasting in microwave and oven on bioactive compounds, antioxidant capacity, fatty acid profiles and phenolic constituents of quinoa seeds for free and conjugated phenolic profile fractions are studied. The oil contents of seeds roasted in both roasting systems were recorded between 4.25% (microwave) and 4.80% (oven).Total phenolic amounts of free and bound fractions of quinoa seeds were measured to be between 1668.1 (control) and 2037.5 mg/100 g (microwave) to 638.9 (microwave) to 1615.3 mg/100 g (oven), respectively. Antioxidant activities of free and bound fractions of quinoa seeds were recorded to be between 36.86% (microwave) and 39.28% (oven) to 74.83% (control) and 77.18% (microwave), respectively. Oleic and linoleic acid results of quinoa seed oils roasted in microwave and oven were identified between 17.26% (oven) and 22.41% (control) to 48.39% (oven) and 59.92% (microwave), respectively. 3,4‐Dihydroxybenzoic acid results of raw and roasted quinoa seeds for free and bound fractions were identified to be between 2.84 (microwave) and 4.01 mg/100 g (oven) to 7.43 (oven) and 12.60 mg/100 g (control), respectively. K results of roasted quinoa seeds were recorded between 8701.17 (oven) and 9638.45 (microwave). Results showed some changes depending on roasting systems and fraction types. [ABSTRACT FROM AUTHOR]

The rapid development of power semiconductor devices is helping to realize a low-carbon society and provide a better life for everyone. Power semiconductors not only are used in many large-scale industrial control fields such as power transmission and control in power grids, rail transit traction systems, and defense weapons and equipment, but also play a vital role in daily equipment such as home appliances, medical electronics, and electronic communications; all devices such as power steering in cars, battery chargers, cell phones, and microwave ovens utilize power electronics. This research mainly focuses on the high-voltage LDMOS device model and its implementation. Based on the in-depth study of the structure and physical mechanism of high-voltage LDMOS devices, with the help of BSIM4 core model, which is now very mature and widely used in industry, the drift region of high-voltage LDMOS is mainly modeled, and the drift region of LDMOS is modeled as a variable resistance controlled by voltage. Finally, Verilog-A language and neural network method are used to establish a compact model of LDMOS. The improved model is applied to LDMOS and can better fit the output characteristics with self-heating effect. [ABSTRACT FROM AUTHOR]

Kefir is a traditional drink produced by the fermentation of milk with kefir grain. In this study, foam-mat drying of kefir using a microwave oven was made, and drying kinetics was determined at various microwave power levels (100, 180, and 300 W). Values of D eff were calculated between 4.8394 × 10 − 10 and 1.8603 × 10 − 9 m2 s-1. Besides, E a was calculated as 5.28 W g-1. Furthermore, increased drying rates were obtained with increasing microwave powers. In addition, seven drying models were fitted to the moisture ratios obtained from experiments, and Midilli and others' model was found to be the best-fitted model with the highest values (0.9983, 0.9983, and 0.9985 for 100, 180, and 300 W, respectively) of R 2 and the lowest values of χ 2 , RSS, and RMSE. [ABSTRACT FROM AUTHOR]

The inorganic elements have unique properties in biochemical processes in humans. An increasing number of pathologies have been associated with essential element ions, such as lead, mercury, and cadmium. Hair has become an attractive clinical specimen for studying the longitudinal exposure to elements from the external environment. Inductively coupled plasma-mass spectrometry (ICP-MS) coupled with nitric acid (HNO3) digestion is the most common approach for determining inorganic elements from human hair. This study aims to optimize the digestion method for the absolute quantitation of 52 elements using ICP-MS, for a large cohort study in human hair. Five different HNO3 (65%) digestion methods were investigated and evaluated for their internal standard solution stability, reproducibility, element coverage, and standard solution recovery efficiency, namely, room temperature for 24 h (RT), 90°C for 4 h (T90), ultrasonic-assisted digestion (UltraS), programmed digestion of microwave digestion (MicroD), and ordinary microwave oven digestion (O-MicroD). Our results demonstrated that O-MicroD, MicroD, and RT were the best performing digestion methods for coefficient of variation (CV) scores, coverage, and recovery efficiency, respectively. In particular, the O-MicroD method detected multiple elements in a small quantity of hair (3 mg), with minimum nitric acid usage (200 μl) and a short digestion time (30 min). The O-MicroD method had excellent reproducibility, as demonstrated by a continuous thousand injections of hair samples with three internal standards (CV: 103Rh = 3.59%, 115In = 3.61%, and 209Bi = 6.31%). Future studies of the elemental content of hair should carefully select their digestion method to meet the primary purpose of their study. [ABSTRACT FROM AUTHOR]

Over the last decades, microwave heating has experienced a great development and reached various domains of application, especially in material processing. In the field of polymers, this unusual source of energy showed important advantages arising from the direct microwave/matter interaction. Indeed, microwave heating allows regio-, chemio-, and stereo-selectivity, faster chemical reactions, and higher yields even in solvent-free processes. Thus, this heating mode provides a good alternative to the conventional heating by reducing time and energy consumption, hence reducing the costs and ecological impact of polymer chemistry and processing. This review states some achievements in the use of microwaves as energy source during the synthesis and transformation of polymers. Both in-solution and free-solvent processes are described at different scales, with comparison between microwave and conventional heating. [ABSTRACT FROM AUTHOR]

Summary: Quick rehydration is the most important characteristic of instant noodles. This study investigated the effects of ingredients on the production and drying methods, the quality, and the rehydration time of instant fermented rice noodles. The dried fermented rice flour was mixed with different amounts of water (80%, 85%, and 90%), guar gum (0.5%, 1.0%, and 1.5%), and potassium chloride (1%, 2%, and 3%). The noodles were dried in a microwave vacuum oven and compared with drying in a hot air oven and a microwave continuous oven. The optimum contents of water, guar gum, and potassium chloride were 80%, 1.5%, and 2%, respectively, because water at 80% resulted in the shortest rehydration time and the highest firmness, guar gum at 1.5% could increase firmness and the water absorption ability to produce the highest cooking yield and firmness with the lowest cooking loss, and potassium chloride at 2% resulted in the shortest rehydration time. Microwave vacuum drying produced the fastest rehydration in hot water for 2 min and the quality of these rehydrated noodles was better than for the other tested drying methods. Microwave vacuum drying generated rapid heat that promoted flash evaporation of the vapour in the noodles, resulting in a porous structure. [ABSTRACT FROM AUTHOR]

This paper reviews the use of domestic microwave ovens as plasma reactors for applications ranging from surface cleaning to pyrolysis and chemical synthesis. This review traces the developments from initial reports in the 1980s to today’s converted ovens that are used in proof-of-principle manufacture of carbon nanostructures and batch cleaning of ion implant ceramics. Information sources include the US and Korean patent office, peer-reviewed papers, and web references. It is shown that the microwave oven plasma can induce rapid heterogeneous reaction (solid to gas and liquid to gas/solid) plus the much slower plasma-induced solid state reaction (metal oxide to metal nitride). A particular focus of this review is the passive and active nature of wire aerial electrodes, igniters, and thermal/chemical plasma catalyst in the generation of atmospheric plasma. In addition to the development of the microwave oven plasma, a further aspect evaluated is the development of methodologies for calibrating the plasma reactors with respect to microwave leakage, calorimetry, surface temperature, DUV-UV content, and plasma ion densities. [ABSTRACT FROM AUTHOR]

The article discusses a study which proposes a microwave heating system that consists multiple microwave cavity and uses a power-controlled phase-shifting mode for heating uniformity. The improved heating uniformity that can be achieved by the proposed mode is demonstrated, highlighting the reduction of the hot and cold spots in the microwave cavity. The proposed system configuration is outlined.

The designed antenna is a monopole Z-shaped antenna operating in an unlicensed band of 2.4 GHz fabricated using low cost inkjet printing technology. The proposed inkjet printing technology is eco-friendly since the material used here is an ordinary "paper" that is suitable for the green technology. The conducting patch of silver nanoparticle (AgNP) ink has very high conductivity 35,700,000 s/m and instant curing property which helps in fabrication process without UV curing or oven heating. The printer used also is the cheap home printer HP DJ 2130 rather than the expensive Brother and Epson printers used in previous works. The printed antenna will be helpful in conditions to ascertain its performance in green agriculture in the form of RF-ID sensors, soil pH value sensor, and moisture sensor. The proposed antenna attains the gain of 2.5 dBi at the ISM band of 2.4 GHz with optimal VSWR value between 1 and 2 over the desired frequency band. The directivity and radiation efficiency of the proposed antenna are 2 dBi and 80%, respectively. The overall cost of the proposed antenna is much lesser in the order of 10 times than the recent low cost design. [ABSTRACT FROM AUTHOR]

The microwave heating characteristics of foods vary with temperature, chemical composition, physical state and geometry. The purpose of the food simulates reported in this paper is to provide heating loads that will enable reliable and reproducible characterization of the heating performance of microwave ovens (2.45 GHz), specifically when heating chilled convenience meals. An extensive literature search was done to identify food simulants that had been used to mimic the heating responses of foods when heated both conventionally and in microwave fields. Each prospective food simulant was initially assessed against a set of criteria that included ease of manufacture, stability and formability. Four meals were chosen to represent the range of chilled convenience meals available in the UK. Tests, using continuous fibre-optic temperature measurement during heating, indicated that the meals could be separated into two broad categories according to heating times, i.e. ‘slow’ and ‘fast’ responders. Food simulants were developed for the two food categories. A good match between food simulant and meal was achieved for the main indicators, i.e. temperatures at central and intermediate locations and weight loss. A close match (a difference of 2% between food simulant and meal) was achieved for the centre location, which is important, as this is often the coolest area in the meal after heating in domestic microwave ovens. [ABSTRACT FROM AUTHOR]

Despite manufacturers' goal of molding single component products from plastics, the structures of some of the products are far too complex to be molded as a single piece. Therefore, assembly of subcomponents into the final products is important for the manufacturing of many plastic-based products. To date, welding is the most efficient joining method for plastics. In this study, multiwalled carbon nanotubes were proposed as the susceptor for the microwave welding of high-density polyethylene considering multiwalled carbon nanotube is a good microwave absorber. multiwalled carbon nanotubes were first dispersed in ethanol in an ultrasonic bath to obtain a homogeneous dispersion. Multiwalled carbon nanotubes dispersion was dropped on the targeted area of the prepared dumbbell-shaped sample and dried in an oven at 45°C for 30 min. The sample was then subjected to 800 W microwave irradiation in the domestic microwave oven. The strength of the weld was tested by using tensile testing. Besides, the cross section of the welded joint was characterized by using scanning electron microscopy. The effect of microwave heating duration and the multiwalled carbon nanotube concentration in the dispersion were studied. It was found that the joint strength increased as the heating duration increase from 2 s to 8 s but decreased when the heating duration was further extended to 10 s. Scanning electron microscopic images showed that voids were formed at the joint interface when 10 s was used and resulted in the lowering of joint strength. In the study of the effect of the multiwalled carbon nanotube concentration in the dispersion, joint strength increased when the multiwalled carbon nanotubes concentration increased from 0.25 wt% to 0.75 wt%. However, the joint strength of sample with 1.00 wt% multiwalled carbon nanotube concentration decreased. The presence of a thick unwelded multiwalled carbon nanotubes layer at the joint interface for sample with 1.00 wt% multiwalled carbon nanotubes concentration as shown in scanning electron microscopic image was believed to cause the lowering of joint strength. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the impact of two convection-microwave heating (M100 and M30) on texture and colour properties, cooking yield and thermal shrinkage of bovine product ( gluteus medius muscle) as compared with conventional roasting at constant temperature (P180 and P80) and roasting with ΔT program (Δ80 and Δ40). The product processed by the M100 method was characterised by high shear force ( WBSF) and high compression force ( TPA). The reduction of microwave intensity to 30% (roasting M30) could improve the tenderness of final product. In addition, microwave heating at the intensity of 30% shortened the roasting time, and the produced sample exhibited comparable process loss and heat shrinkage extent compared to those treated by the high-temperature conventional roasting method (P180). The study indicated that combining of convection and low-intensity microwave heating could be successfully used in catering business for beef roasting due to the shorter cooking time, reduced cooking loss and higher tenderness of meat. [ABSTRACT FROM AUTHOR]

Despite manufacturers' goal of molding single component products from plastics, the structures of some of the products are far too complex to be molded as a single piece. Therefore, assembly of subcomponents into the final products is important for the manufacturing of many plastic-based products. To date, welding is the most efficient joining method for plastics. In this study, multiwalled carbon nanotubes were proposed as the susceptor for the microwave welding of highdensity polyethylene considering multiwalled carbon nanotube is a good microwave absorber. multiwalled carbon nanotubes were first dispersed in ethanol in an ultrasonic bath to obtain a homogeneous dispersion. Multiwalled carbon nanotubes dispersion was dropped on the targeted area of the prepared dumbbell-shaped sample and dried in an oven at 45°C for 30 min. The sample was then subjected to 800W microwave irradiation in the domestic microwave oven. The strength of the weld was tested by using tensile testing. Besides, the cross section of the welded joint was characterized by using scanning electron microscopy. The effect of microwave heating duration and the multiwalled carbon nanotube concentration in the dispersion were studied. It was found that the joint strength increased as the heating duration increase from 2 s to 8 s but decreased when the heating duration was further extended to 10 s. Scanning electron microscopic images showed that voids were formed at the joint interface when 10 s was used and resulted in the lowering of joint strength. In the study of the effect of the multiwalled carbon nanotube concentration in the dispersion, joint strength increased when the multiwalled carbon nanotubes concentration increased from 0.25 wt% to 0.75 wt%. However, the joint strength of sample with 1.00 wt% multiwalled carbon nanotube concentration decreased. The presence of a thick unwelded multiwalled carbon nanotubes layer at the joint interface for sample with 1.00 wt% multiwalled carbon nanotubes concentration as shown in scanning electron microscopic image was believed to cause the lowering of joint strength. [ABSTRACT FROM AUTHOR]

Hierarchical copper oxide (CuO) microspheres were prepared by a simple microwave-assisted preparation method in an ordinary household microwave oven under ambient pressure. The CuO microspheres were characterised by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and thermal gravimetric analysis. Characterisation results show that the hierarchical CuO microspheres are assembled by spine-like nanorods and have high Brunauer–Emmett–Teller surface area of 25.0 m²/g. [ABSTRACT FROM AUTHOR]

Summary: Broccoli and green asparagus were cooked using boiling water, steam, microwave oven and combi oven with overheated steam and combination of hot air with overheated steam (only broccoli). Vegetables were analysed for chlorophylls a and b, carotenoids, total polyphenols, antioxidant activity, colour parameters and sensory properties. Cooking in the combi oven with overheated steam was an effective method to achieve the highest levels of polyphenols and antioxidant activity, but it negatively influenced the contents of chlorophylls in both vegetables and carotenoids in asparagus. Boiling and cooking in the combi oven with overheated steam or hot air and steam ensured the best and comparable sensory properties of broccoli. Asparagus showed a lower susceptibility to heat treatments than broccoli as none of the treatments applied caused significant differences in colour redness and yellowness, polyphenol content and sensory properties of this vegetable. [ABSTRACT FROM AUTHOR]

The effects of pulsed vacuum osmotic dehydration (PVOD) and ultrasound osmotic dehydration (USOD) on drying characteristics and quality attributes of ginger were investigated. PVOD was subjected to pulsed vacuum at 13 kPa for 30 min, and USOD was subjected to ultrasound with the frequency of 40 kHz for 30 min. After PVOD and USOD treatments, the samples were then dried at intermittent microwave & air‐drying oven with an output of 700 W and temperature of 60°C to the final moisture content of 0.12 g water/g d.w. The results showed PVOD and USOD treatments could improve the total phenolic contents by −1.8% to 16.4%, total flavonoid content by 7.7%–18.7%, DPPH radical scavenging by 9.5%–12.2%, and ABTS+ antioxidant activity by 17.8%–27.4%, although they prolonged the later stages drying of ginger. Besides, the PVOD‐ and USOD‐pretreated dried samples had less brownings than the untreated‐dried samples which could be attributed to the inactivation of polyphenol oxidase (PPO) and peroxidase (POD). The PPO activity was significantly reduced in the PVOD and USOD ginger, whereas POD activity was decreased in USOD ginger but increased in PVOD ginger. Moreover, PVOD pretreatment also led to a better preservation of volatile profiles and cell structure than USOD treatment. Therefore, both PVOD and USOD are effective pretreatments for drying of ginger. [ABSTRACT FROM AUTHOR]

Deep-fried instant noodles were cooked in a microwave oven at 557 W (medium power) and 657 W (full power). The microwave cooking times were determined based on textural parameters and the qualities of microwave oven cooked noodles at medium power and full power were compared with those of products cooked using a conventional gas stove for 9.1 min (CON). Heating in the microwave increased the temperature of the noodle block faster than the cooking water, led to an increased degree of gelatinisation of instant noodles, and reduced the cooking times to 8.5 min (medium power) and to 7.5 min (full power). Cooking in the medium power microwave resulted in high water absorption and weak hardness values. Cooking in the full power microwave resulted in higher hardness and tensile strength than the medium power microwave and sensory evaluated organoleptic scores were comparable to the CON, despite having a significantly higher rancidity. [ABSTRACT FROM AUTHOR]

The effects of three cassava cultivars produced in Brazil were assessed ( IAC Espeto, IAC 14 and IAC Caapora) in order to obtain chips by precooking and hot air-microwave drying (70 °C, 95 W). The difference in the composition of cultivars has not influenced the drying of cassava slices. The drying kinetics presented a constant drying rate period followed by a decreasing drying rate with effective diffusion coefficient of 2.8-3.0 × 10−10 m2s−1. The hedonic means of all attributes ranged from 'neither like nor dislike' to 'like moderately'. Therefore, the choice of the more suitable cultivar can be based on plant productivity and product yield. The IAC 14 cultivar resulted in the highest root production per plant, product mass per roots and chips yield. [ABSTRACT FROM AUTHOR]

Summary Food processors are increasingly looking towards new microwave-based technologies to deliver competitive advantage in the market place, reduce operational costs, allow greater product innovation and increase flexibility without the need for large capital investments. The technical barriers to the widespread exploitation of microwave heating, and opportunities for microwave heating in food processing, are discussed in the context of the need to understand the microwave field/material/process interaction. It is shown how a new application of interference techniques, called phase control microwave heating, may offer opportunities for enhanced heat transfer in food processing, especially for direct control of the spatial power deposition within a foodstuff. Simulations of phase control heating using a 3D FETD microwave model, validation of experimental findings and examples in other applications are presented. [ABSTRACT FROM AUTHOR]

We present an oven-controlled FBAR oscillator that achieves a frequency stability of +/-1.55ppm from -5°C to 85°C. The highly integrated system includes a 0.64mm2 FBAR chip with integrated heater and sensor resistors and a 3 mm2 CMOS chip with the control electronics. The oscillator achieves an Allen deviation of 4ppb enabled by a temperature-to-digital converter (TDC) with a 150uK resolution. It corresponds to a 1.68JK2 FOM. The heater consumes a power of 14mW at -5°C and the oscillator consumes only 0.25mW. The ovenized oscillator meets the stringent frequency stability requirements (2 ppm) of GPS applications. [ABSTRACT FROM AUTHOR]

Roasting enhances sensory quality of wild almonds ( Amygdalus scoparia). The aim of the study was to evaluate the use of microwaves (480 W for 3 or 4 min) in roasting of wild almonds in comparison with traditional Spanish (165 °C for 20 min) and Iranian (soaking in 20 % NaCl in water for 30 min, drying at 60 °C for 2 h and roasting at 135 °C for 20 min) hot-air processes. The influence of roasting wild almonds on moisture and oil contents, crispness, fatty acid profile, volatile compounds, and odour intensity was investigated. Roasting causes changes in appearance, texture and flavour, due to dehydration, browning, lipid oxidation, and diverse structural changes. The moisture content and hardness of the samples significantly decreased with all roasting methods. Roasting resulted in higher amounts of characteristics aroma compounds and only microwave roasting increased the oil content. The final recommendation is that microwave roasting at 480 W for 4 min led to roasted almonds of high physicochemical [dark and intense colour ( L*44.9, a*8.4, and b*19.6), the highest content of total volatile compounds (132 mg kg), 85.2 % of unsaturated fatty acids], and sensory (high intensity of 'roasted almond' aroma) quality. Microwaves can be used for roasting wild almond as a quick, safe, and economical method. [ABSTRACT FROM AUTHOR]

The effect of microwave-assisted convective air-drying on the drying kinetics and quality of mango was evaluated. Both microwave power and pretreatment time were significant factors but the effect of power was more profound. Increase in microwave power and pretreatment time had a positive effect on drying time. The nonenzymatic browning index of the fresh samples increased from 0.29 to 0.60 while the ascorbic acid content decreased with increase in microwave power and time from 3.84mg/100g to 1.67mg/100g. The effective moisture diffusivity varied from 1.45 × 10-9 to 2.13 × 10-9 m²/s for microwave power range of 300-600 W for 2 to 4 minutes of pretreatment. The Arrhenius type power-dependent activation energy was found to be in the range of 8.58-17.48 W/mm. The fitting of commonly used drying models to the drying data showed the Midilli et al. model as the best. Microwave power of 300 W and pretreatment time of 4 minutes emerged as the optimum conditions prior to air-drying at 7°C. At this ideal condition, the energy savings as a result of microwave application was approximately 30%. Therefore, microwave-assisted drying should be considered for improved heat and mass transfer processes during drying to produce dried mangoes with better quality. [ABSTRACT FROM AUTHOR]

The electromagnetic field leakage levels of nonionizing radiation from a microwave oven have been estimated within a complex indoor scenario. By employing a hybrid simulation technique, based on coupling full wave simulation with an in-house developed deterministic 3D ray launching code, estimations of the observed electric field values can be obtained for the complete indoor scenario. The microwave oven can be modeled as a time- and frequency-dependent radiating source, in which leakage, basically from the microwave oven door, is propagated along the complete indoor scenario interacting with all of the elements present in it. This method can be of aid in order to assess the impact of such devices on expected exposure levels, allowing adequate minimization strategies such as optimal location to be applied. [ABSTRACT FROM AUTHOR]

Various aryl aldehydes underwent prompt one pot conversion into the corresponding azomethines in high yields by reacting with hydroxylamine hydrochloride supported on melamine formaldehyde under microwave irradiation. [ABSTRACT FROM AUTHOR]

Diopside ( Ca Mg Si2 O6) ceramics was synthesized and fabricated by a simple solid-state reaction rather than other used processes. This new and economic approach for diopside fabrication consists mainly of replacing the usually used starting materials by other more economic (activated Ca O· Mg O powders), using conventional sintering and microwave sintering. The P2 O5 addition (0.5-5.0 wt%) promotes sintering, crystallization, and bioactivity. Additionally, a considerably low weight loss ratio (0.21%) was also obtained for these samples, after 2 days of soaking in lactic acid. Carbonated hydroxyapatite ( CHA) formation in simulated body fluid was confirmed for all sintered samples. Both sintering and CHA formation mechanisms were proposed. [ABSTRACT FROM AUTHOR]

In this work, both planar and textured, industrial scale (156 mm × 156 mm) single-crystalline silicon ( Si) solar cells have been fabricated using zinc oxide ( ZnO) nanorods as antireflection coating ( ARC). ZnO nanorods were grown in a few minutes via hydrothermal method within a commercially available microwave oven. Relative improvement in excess of 65% in the reflectivity was observed for both planar and textured Si surfaces. Through ZnO nanorods, effective lifetime (τeff) measurements were presented to investigate the surface passivation property of such an ARC layer. ZnO nanorods increased the τeff from 9 to 71 μs at a carrier injection level of 1015 cm−3. Increased carrier lifetime revealed the passivation effect of the ZnO nanorods in addition to their ARC property. 33% and 16% enhancement in the photovoltaic conversion efficiency was obtained in planar and textured single-crystalline solar cells, respectively. Our results reveal the potential of ZnO nanorods as ARC that can be deposited through simple solution-based methods and the method investigated herein can be simply adapted to industrial scale fabrication. [ABSTRACT FROM AUTHOR]

Polyacrylonitrile (PAN)/Montmorillonite (MMT) clay nanocomposite was prepared in a microwave oven using a transition metal Co(III) complex taking ammonium persulfate (APS) as initiator with a motive of converting hydrophobic PAN into hydrophilic nanocomposite material via nanotechnology by the inclusion of MMT to the virgin polymer. UV-visible spectral analysis revealed various interactions between the developed complex with other reaction components. The formation of the PAN/MMT nanocomposites was characterized by FTIR. Furthermore, as evidenced by X-ray diffraction (XRD), transmission electron microscopy (TEM), the composite so obtained was found to have nano-order. XRD and TEM were suggesting that montmorillonite layers were exfoliated during the polymerization process. An increasing in the thermal stability for the developed nanocomposite was recorded by thermogravimetric analysis (TGA). The water absorption and biodegradation properties were carried out for its ecofriendly nature and better commercialization. [ABSTRACT FROM AUTHOR]

The reaction rate of Knoevenagel condensation can be dramatically enhanced by irradiating the reaction mixture containing an aldehyde, active methylene compound, L-proline and chlorobenzene with a commercial microwave oven. Twenty Knoevenagel condensation products were synthesized within 5-17 min in good yields. The new compounds were also screened for their antibacterial activity. [ABSTRACT FROM AUTHOR]

Commercial, nonthermal processing of food, such as high hydrostatic-pressure processing (HPP), has increased. The safety and quality of foods produced by HPP has not been well communicated to the public. An online, nationwide consumer survey was implemented to assess awareness of alternative food processing technologies, consumer food safety attitudes and knowledge, and willingness to pay (WTP) for HPP products. The consumer survey was administered by Zoomerang™, an online survey clearinghouse. The survey was completed by 1204 adults. Frequencies and crosstabs were calculated on Zoomerang and SPSS used for one-way ANOVA and chi-square analyses. The survey assessed knowledge of HPP, attitudes about new food processing techniques, WTP for HPP foods and demographics. Overall, many demographic characteristics reflected U.S. census population. While traditional methods, that is, canning, freezing, and microwaving were all well recognized by over 80% of respondents, only 8% recognized HPP. Trends indicated an increase in age, education, and income reflected greater food safety knowledge. Regardless of demographics, no survey respondent exhibited knowledge mastery (80%). Given an explanation of HPP and its benefits, 39% of respondents indicated they would be WTP an additional cost, with higher income and education having the most impact. Majority of respondents indicated a WTP of $0.25 to $0.50 regardless of the value of the food product. More respondents were WTP slightly more for a more expensive product. New technologies often encounter a stumbling block in consumer acceptance and processing costs. A consumer's WTP, once they were informed, could encourage industry to look favorably on this technology. [ABSTRACT FROM AUTHOR]

This study elucidates the capability of a novel technique for producing microcapsules at an enormously short time and low cost. This technique is based on the difference between dielectric constants of core and coat materials. Edible citric acid was mixed with various biomacromolecules at ratios of 1:5, 1:10, and 1:100. Each mixture was treated up to 600 s at various powers (120–1200 W) in a microwave oven. Subsequently, the microcapsules were separated by distinct sieves, and their apparent structure and quality were evaluated using binoculars, and photographs were taken for visual comparisons. Our observations showed that only five hydrocolloids were able to produce high-quality and efficient encapsulation [casein > inulin > carboxymethylcellulose (CMC) > low methoxyl (LM) pectin (9/5%) > sorbitol]. Moreover, the highest coating efficiency was seen at highest intensity (1200 W) at a mixing ratio of 1:10. Furthermore, the optimum treating time periods for those five efficient coating materials were about 400, 75, 400, 100, and 100 s. [ABSTRACT FROM AUTHOR]

An interview with Professor Wang-Sang Lee from Gyeongsang National University in South Korea is presented. He talks about his research on the field of microwave ovens, focusing on the background to the work he performed in his paper about microwave heating system which was published in the issue. Lee discusses the significance of the research and the challenges he overcame, especially in mathematically modeling the electric field strength.

Provides information on several patent applications in Europe as of September 6, 2004. Snowmobile with a remote ignition system from Arctic Cat of Minnesota; Paint drying system from Junair Spraybooths of England; Oil-reducing microwave oven from Samsung Electronics of Korea.

Bone loss in the alveolar ridge is a factor widely studied by dentists in implant surgeries, as it poses a major challenge for aesthetic and functional recovery in patients with large maxillary bone defects. Synthetic biomaterials function as grafts designed to replace and remodel bone tissue. Calcium phosphate is a biomaterial that has good properties such as biocompatibility and bioactivity, making it a reference in bone replacement treatments. A synthetic biomaterial such as calcium phosphate can be obtained by various synthesis techniques. The microwave hydrothermal method (HTMO) is a pathway that allows changes in synthesis parameters and significantly increases the transmission efficiency of materials such as synthetic calcium phosphate derivatives. The study proposes obtaining a biomaterial for bone grafting based on calcium phosphate by the microwave HTMO and evaluating its microstructural and physicochemical characteristics. The parameters tested in this process were temperature and reaction time. The calcium phosphate particulates were obtained by the microwave HTMO at temperatures of 110°C and 130°C for 60 min and calcined at 300°C, 500°C, and 700°C. Microstructural and physicochemical characterization analyses were carried out using scanning electron microscopy, Fourier transform infrared, and X‐ray diffraction. The results obtained showed the presence of more than one calcium phosphate biological interest phase, as hydroxyapatite (HA), tricalcium phosphate (β‐TCP), and octacalcium phosphate (OCP), highlighting with increasing calcination temperature, the β‐TCP phase becomes evident. The proposed synthesis method was efficient in obtaining a biomaterial with suitable physical and chemical characteristics, with an association of crystalline phases of biological interest related to the increase in synthesis temperature and calcination temperature. [ABSTRACT FROM AUTHOR]

In light of the anticipated 50% increase in global energy demand by 2050, the demand for innovative, environmentally conscious, efficient, and dependable energy technologies is paramount. Solid oxide fuel cells (SOFCs) offer a promising solution for sustainable energy production. This comprehensive review provides a detailed analysis of SOFCs, covering their fundamentals, materials, performance, and diverse applications, while also addressing technological challenges and future prospects. The review emphasizes the key advantages of SOFCs, including their high efficiency of up to 60% and minimal environmental impact. It explores the significance of impurity resistance and durability in materials and manufacturing processes for SOFC components. Comparative evaluations demonstrate the superior energy efficiency and ecological effects of SOFCs compared to other fuel cell technologies. SOFCs' versatility and potential are showcased through their applications in transportation, power generation and storage, portable devices, and residential usage. However, challenges such as cost, longevity, reliability, and integration with other energy systems are identified, emphasizing the need for supportive policies and regulations. [ABSTRACT FROM AUTHOR]

Recent advances in wearable electronics have been propelled by the rapid growth of microelectronics and Internet of Things. The proliferation of electronic devices and sensors relies heavily on power sources, predominantly batteries, with significant implications for the environment. To address this concern and to reduce carbon emissions, there is a growing emphasis on renewable energy harvesting technologies, among which textile‐based triboelectric nanogenerators (T‐TENGs) stand out as an innovative and sustainable solution due to having the interesting characteristics like large contact area, lightweight design, flexibility, comfort, scalability, and breathability. T‐TENGs can harness mechanical energy from human movement and convert it into electric energy. However, one of the challenges is low electric power output, which can be addressed by meticulous selection of material pairs with significant differences in work function and optimizing contact areas. The incorporation of carbon‐based nanomaterials, such as carbon nanotubes and graphene, emerges as a key strategy to enhance output. This review delineates recent progress in T‐TENGs incorporating carbonaceous nanofillers, comprehensively addressing fundamental classification, operational mode, structural design, working performance, and potential challenges that are hindering commercialization. By doing this, this review aims to stimulate future investigations into sustainable, high‐performance smart wearables integrated with T‐TENGs. [ABSTRACT FROM AUTHOR]

In this work, we investigated a procedure which exploits microwave ovens to produce SiC‐ based components by reactive melt infiltration of silicon into graphite preforms. The employed oven is designed to grant optical access to the sample surface, which allows to measure its temperature evolution though a noncontact pyrometer. This signal was used as a feedback to control the power provided to the preform and as an experimental output whose analysis provides insight into the reaction mechanism. Specifically, it is found that complete infiltration is achieved much before the end of the reaction. The latter is not fully self‐sustained as the global reaction rate continuously decreases with time until it is no more able to keep the temperature above the silicon solidification value. At that point, the reaction stops. The analysis of the processed samples proved that this procedure allows producing fully infiltrated samples without material failure by adjusting the heat provided during the infiltration stage rather than by tuning the preform structure and composition, which is the usual approach. The proposed method is less time and energy consuming than the standard one. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) are an emerging class of nanomaterials with attractive optical properties, which promise to enable a variety of applications. An important and timely question is whether CDs can become a functional and sustainable alternative to incumbent optical nanomaterials, notably inorganic quantum dots. Herein, the current CD literature is comprehensively reviewed as regards to their synthesis and function, with a focus on sustainability aspects. The study quantifies why it is attractive that CDs can be synthesized with biomass as the sole starting material and be free from toxic and precious metals and critical raw materials. It further describes and analyzes employed pretreatment, chemical‐conversion, purification, and processing procedures, and highlights current issues with the usage of solvents, the energy and material efficiency, and the safety and waste management. It is specially shown that many reported synthesis and processing methods are concerningly wasteful with the utilization of non‐sustainable solvents and energy. It is finally recommended that future studies should explicitly consider and discuss the environmental influence of the selected starting material, solvents, and generated byproducts, and that quantitative information on the required amounts of solvents, consumables, and energy should be provided to enable an evaluation of the presented methods in an upscaled sustainability context. [ABSTRACT FROM AUTHOR]

The escalating incidence of health issues linked to environmental pollutants, specifically endocrine‐disrupting chemicals (EDCs), has emerged as a dire consequence of modern industrialization. Bisphenol A (BPA), a widespread EDC, is under scrutiny for its potential role in exacerbating bladder cancer via the modulation of cancer‐associated fibroblasts (CAFs). CAFs are integral to the tumor microenvironment, influencing cancer progression through their interactions with immune cells and secretion of various factors and exosomes. By recognizing the critical role of CAFs, this study delves into their utility as therapeutic targets, focusing on the identification of reliable biomarkers within CAFs for bladder cancer. Through weighted correlation network analysis, genes associated with T cell activity were pinpointed, culminating in the creation of a CAFs‐based, immune‐related gene prognostic model. Central to this model is ANPEP, an enzyme whose expression level not only serves as an indicator of T cell infiltration but also implicates a substantial role in the CAF‐mediated immunotherapy responses for bladder cancer. Our investigation posits ANPEP as a linchpin in regulating CAF functions, offering a novel perspective wherein targeting ANPEP may reduce the adverse side effects commonly associated with traditional immunotherapies. Furthermore, ANPEP‐targeted strategies could lessen the tumor mutational burden in bladder cancer patients. Empirical evidence from our proliferation and invasion assays indicates that heightened ANPEP expression is correlated with diminished patient survival. These insights pave the way for tailored immunotherapeutic approaches in bladder cancer treatment, emphasizing the modulation of CAFs by ANPEP. [ABSTRACT FROM AUTHOR]

Application of physical forces, ranging from ultrasound to electric fields, is recommended in various clinical practice guidelines, including those for treating cancers and bone fractures. However, the mechanistic details of such treatments are often inadequately understood, primarily due to the absence of comprehensive study models. In this study, we demonstrate that an alternating magnetic field (AMF) inherently possesses a direct anti‐cancer effect by enhancing oxidative phosphorylation (OXPHOS) and thereby inducing metabolic reprogramming. We observed that the proliferation of human glioblastoma multiforme (GBM) cells (U87 and LN229) was inhibited upon exposure to AMF within a specific narrow frequency range, including around 227 kHz. In contrast, this exposure did not affect normal human astrocytes (NHA). Additionally, in mouse models implanted with human GBM cells in the brain, daily exposure to AMF for 30 min over 21 days significantly suppressed tumor growth and prolonged overall survival. This effect was associated with heightened reactive oxygen species (ROS) production and increased manganese superoxide dismutase (MnSOD) expression. The anti‐cancer efficacy of AMF was diminished by either a mitochondrial complex IV inhibitor or a ROS scavenger. Along with these observations, there was a decrease in the extracellular acidification rate (ECAR) and an increase in the oxygen consumption rate (OCR). This suggests that AMF‐induced metabolic reprogramming occurs in GBM cells but not in normal cells. Our results suggest that AMF exposure may offer a straightforward strategy to inhibit cancer cell growth by leveraging oxidative stress through metabolic reprogramming. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to compare the flexural strength of monolithic zirconia with different thicknesses and two sintering techniques. Materials and Methods: This in vitro, experimental study was conducted on 28 monolithic zirconia discs with 10 mm diameter and 0.5 (n = 14) and 1.2 mm (n = 14) thickness. Each group was divided into two subgroups (n = 7) for fast (60 min) and conventional (120 min) sintering at 1450°C. After sintering, the specimens were thermocycled and their flexural strength was measured by piston‐on‐3‐balls technique in a universal testing machine (0.5 mm/min, 1.2 mm pin diameter). Data were analyzed by the Weibull test, one‐way analysis of variance, and Tukey's test (α =.05). Results: The flexural strength of specimens with 1.2 mm thickness was significantly higher than that of specimens with 0.5 mm thickness (p <.05). The flexural strength of 1.2 mm/120‐min group was slightly, but not significantly, higher than that of 1.2 mm/60‐min group (p >.05). The flexural strength of 0.5 mm/120‐min group was slightly, but not significantly, higher than that of 0.5 mm/60‐min group (p >.05). Conclusion: The increase in thickness of monolithic zirconia increases its flexural strength; however, increasing the sintering time appears to have no significant effect on the flexural strength of monolithic zirconia. [ABSTRACT FROM AUTHOR]

With the rapid advancement of modern technology, flexible and wearable electronics, particularly electromechanical sensors, have gained considerable attention for motion‐based applications in medical health monitoring and artificial intelligence. Correspondingly, extensive efforts have been dedicated to enhancing their performance and practicality. Electromechanical sensors based on functional composites and structures accurately detect and monitor the body, generating the corresponding output signals. However, there are several limitations in manufacturing composite sensors, such as the selection and combination of functional materials, geometrical structures, constructed conductive pathways, stability of output signals, and operational lifetime. Thus, this review summarizes notable trends in the electromechanical sensors using functional composites and structures. This also provides an overview of different types of electromechanical pressure and strain sensors, exploring their operational mechanisms regarding triboelectricity, piezoelectricity, piezocapacitance, and piezoresistivity. The unique characteristics of functional materials, including conductive polymers, nanostructured metals, and carbon nanomaterials and composites, are analyzed alongside various design concepts for highly flexible and stretchable sensors. Furthermore, potential applications concerning human motion and human–machine interfaces are also recommended. Additionally, several future outlooks are reviewed for insights into future prospects and strategies. Thus, this review can assist readers in understanding current electromechanical devices more accurately. [ABSTRACT FROM AUTHOR]

Microwave drying of plant specimens is a potentially useful alternative to chemical and traditional air drying pres-ervation techniques because microwave ovens are widely available, and the method is quick and inexpensive and kills pests without leaving toxic residue. We tested the hypotheses that (1) there would be a difference in the concentration of genomic DNA that could be extracted from microwave-dried compared to silica-dried specimens, (2) the effects of microwave treatment would be observable even when the specimen had been first dried in silica gel crystals, (3) the effects of microwave drying would continue to be observable in PCR product concentration using chloroplast, nuclear ribosomal, and nuclear markers, and (4) microwave drying would cause contamination of the nucleic acids by cell material, and this contamination would be reflected in the spectral absorbance of the extracted genomic DNA. In a paired comparison of silica-dried, microwave-dried, and silica+microwave-treated leaves of Brosimum alicastrum (Moraceae) we found that microwave drying produced spec-imens with bright leaf colour, which to date have not suffered from insect or fungal attack. However microwave treatment significantly reduced the concentration of extractable genomic DNA, even when the leaves had been previously dried in silica gel, and reduced the concentration of PCR product produced using chloroplast and nuclear ribosomal but not nuclear markers. The genomic DNA extracted from both the microwave-dried and silica+microwave-treated material appears to contain some cellular contaminant which absorbs at 230 nm, indicated by low 260/230 nm absorbance ratios. We suggest that microwave drying is a useful alternative to chemical preservation techniques which limit the capacity for DNA extraction from preserved material. However microwave drying is less desirable than traditional air- or oven drying or the combination of traditionally dried herbarium specimens plus companion samples dried in silica gel crystals. [ABSTRACT FROM AUTHOR]