By transferring technologies for food products from North Carolina to Africa, Muzhingi hopes to have a huge economic impact from creating new jobs and inspiring entrepreneurs to enhancing food security and improving nutrition.
Sweet potato is just the first highly nutritious crop Muzhingi has focused on to showcase the power of agro-processing for food security and economic development. He hopes to expand the collaboration with NC State to other crops and food processes, innovations coming out of the Plant Sciences Initiative and beyond.
Advantages Of Economic Microwaves
Conversely, with microwaves, heating the volume of a material at substantially the same rate is possible. This is known as volumetric heating. Energy transfers through the material electro-magnetically, not as a thermal heat flux. Therefore, the rate of heating is not limited. As a result, the uniformity of heat distribution greatly improves. Heating times reduce to less than one percent of that required using conventional techniques.
A common misconception is that microwave heating is always more expensive than heating by conventional techniques. The actual answer depends on the application and local utility costs. In some cases, microwaves can be more efficient than conventional systems, resulting in major savings in energy consumption and cost.
In addition to the applications above, IMS planar units act as Stand-Alone Dryers. These may be the most economical solution. Especially where minimal equipment floor space or footprint is available for a new application. Or, when expansion of existing production facilities would require building modifications to accommodate a conventional drying system.
Microwaves are incredibly popular in Australia. In fact, according to Canstar Blue Research, in 2013, around 96% of all Australian households owned one or more microwaves. Moreover, over the last couple of years, 28% of all people surveyed said that they purchased a new microwave.
While microwaves offer a wide range of advantages, I admit that they also do suffer from a few drawbacks. First of all, you have to be conscious and cautious of what materials and utensils you place in a microwave. A dish that is no microwave-safe will set off a chemical reaction between the food and the plastic resulting in a melted dish and uneatable food.
Sterilisation via microwave exposure has been developed through microwave heating and a series of treatments. Microwaves between 225 MHz to 100 GHz are primarily suited for sterilisation: the main microwaves used for heat sterilization of food in this range are at 2.45 GHz [32]. 2.45 GHz microwaves have also proven to be able to sterilise glass and plastics in as little as 180 s; this too requires the presence of water within the microwave to act as a heat sink and interact with the electromagnetic waves. This method of sterilisation can be used on both laboratory and medical equipment in place of an autoclave [33,34].
Another use of thermal interactions is Microwave Metal Sample preparation through microwave digestion. Microwave digestion is a technique to dissolve heavy metals in the presence of organic matter. This process exposes samples to strong acids and then raises the temperature using focused microwaves. This method can be used for environmental samples to measure contaminants that could affect human health, such as lead. For samples of soil to be analysed, they must be transformed into liquid samples through microwave digestion. The samples can then be analysed via Inductively coupled plasma mass spectrometry (ICP-MS) for trace metals or flame atomic absorption spectroscopy (FAAS) for major elements [35]. Microwave digestion and the subsequent spectrophotometry can be used to analyse trace metals in human tissue such as hair, nails and gallstones. Gallstones have trace amounts of metal that are associated with bilirubinate and black pigmented gallstones, thus by determining the amounts and variety of metals within gallstones their origin of these metals may be determined [36,37].
Microwaves can play a role in both the detection and treatment of breast cancer. Microwave imaging has been researched as an alternative to X-rays and ultrasound screening which have a variety of limitations [5,50]. Microwave imaging is an appropriate alternative as it is a low cost, harmless and potentially easier to perform compared to current methods with high sensitivity. Imaging techniques rely on the knowledge of the permittivity and conductivity of malignant, benign and healthy breast tissue. Due to the higher water content in cancer cells the dielectric properties of the tissue differs when exposed to microwaves [51]. Despite the nearly 40 years of research into microwave breast imaging, there are still many limitations that prevent a commercially available device that include inappropriate algorithms and sensors; however, with wider clinical trials a viable microwave imaging system may be feasible in the near future [39,40]. Microwave ablation has also been trialled for the treatment of breast cancer and so far has proved to be successful in thermal ablation [52,53].
Other than ablation and rapid heating, treatments for damaged and keratinized cells have been researched and developed with controlled heating. The Swift microwave is an approved state of the art treatment for plantar warts caused by the human papillomavirus (HPV). Directly exposing the wart to 8 GHz microwaves at 8 Watts for 2 s causes the wave to interact with the keratinized skin and results in controlled heating of the tissue. There is also the suggestion that microwaves enhance the cross-presentation of dendritic cells that are key for the immune defence against HPV [54,55]. A similar method has been developed for the potential treatment of actinic keratosis (AK). The Swift 8GHz microwave is used to expose the ulceration to 4 W for hyperkeratotic AK or 3 Watts for nonhyperkeratotic AK for 3 s repeated in triplicate with a 20-s time gap between pulses. This treatment has resulted in the clearance of actinic keratosis with brief pain and minimal long term adverse side effects in 90% of applied sites [56]. Following this, the use of microwaves to treat benign cancerous and precancerous lesions caused by high-risk HPV was investigated. High-risk HPV results in an increased expression of 2 viral oncoproteins; E6 and E7. When in vitro- grown tumours were exposed to microwaves for 10 s both tumour cell death and a reduction in E6 and E7 in the treated zone and transition zone were observed. This reduction suggests that microwave interactions can reverse the cancerous phenotype caused by HPV; and that once an effective and proven method is developed it could provide a less invasive treatment for HPV benign tumours [57,58].
State of the art microwave-based molecular diagnostics that incorporate the non-thermal effects of microwaves are currently under development to tackle the delays and complexities of current methods; these include microwave assisted metal enhanced fluorescence and nanotube assisted microwave electroporation. Microwave assisted metal enhanced fluorescence (MAMEF) is a rapid diagnostic method being developed to detect bacterial infections at point of care. MAMEF combines the use of silver nanoparticles deposited on microscope slides which are impregnated with anchored DNA sequences specific to the target sequence- such as a bacterial species [59,60]. Low power microwave heating kinetically accelerates the hybridisation of the target DNA and a fluorescent DNA target (usually a conserved region of bacterial genomic DNA) is excited and detected by the process. This method is currently crude and not yet manufactured for wider laboratory use [61]. If commercialized appropriately and manufactured into an integrated device, MAMEF would be a useful point of care diagnostic due to its speed, specificity, low cost and simplicity [62].
MAMEF and Lyse-It are not the only devices exploiting the proposed non-thermal effects of microwaves as a method of DNA extraction for molecular diagnostics. Methods using microcentrifuge tubes as an alternative to the expensive Lyse It slides are being researched, however, these processes are still somewhat time-consuming due to the required centrifuge and wash procedures [66]. Development of other rapid diagnostic devices that utilize microwave-based DNA extraction and fragmentation as a first step to sample processing is in the early stages of development [67].
The global need for power to provide ubiquitous connectivity through 5G, 6G, and smart infrastructure is rising. This report explains the prospects of power beaming; its economic, human, and environmental implications; and the challenges of making the technology reliable, effective, wide-ranging, and secure.
The microwave heating/healing technique is regarded as a green maintenance approach for asphalt pavements thanks to its promising environmental and economic benefits. However, the main concern about this technology is represented by the possible aging effect generated on bituminous binders. Currently, there is a significant lack of studies dealing with this topic. Based on these premises, the main purpose of this study is to appraise the feasibility of implementing microwave-based maintenance operations considering the associated aging effect. The assessment of fatigue life after cyclic microwave heating (MH) based on a linear amplitude sweep (LAS) test and the changes in the chemical groups detected through Fourier transform infrared (FTIR) spectroscopy document the aging phenomenon. The results indicate that the microwave aging degree on bituminous binder is nonlinear with MH cycles. The microwave radiation causes a distinct aging impact on binders during the first 10 cycles, then the values become constant. Furthermore, a feasibility analysis of MH technology is developed, encompassing four main multidisciplinary aspects: evaluation of microwave aging degree, working mechanism of MH equipment, safety assessment, and economic and ecological considerations. Despite the associated aging issue, the MH method is an efficient technology, considering its various advantages (i.e., rapidity of execution, uniform and non-pollutant treatment, and deep penetration). Meanwhile, the use of steel slag as a microwave absorber bolsters the sustainability of MH technology. This study provides a new perspective to evaluate the microwave heating technique in road engineering comprising the generated aging effect. Practice-oriented recommendations are also formulated regarding the safe implementation of MH technical operations. 2ff7e9595c
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