Measuring the dielectric properties of date palm fruit, date palm leaflet, and Dubas bug at radio and microwave frequency using two-port coaxial transmission/reflection line technique

Zadeh, Motahareh Vaezi; Afrooz, Kambiz; Shamsi, M.; Rostami, M. Ali

doi:10.1016/j.biosystemseng.2019.03.003

Cited by 13 publications

(6 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Dielectric properties of the yellow fever mosquito mixture were obtained using coaxial-probe measurements from 5–67 GHz. Previous studies [ 6 , 23 , 24 , 43 – 46 ] have also investigated dielectric properties of insects in this frequency range, some of these values for ϵ ′ and ϵ ” are given in Fig 7 , together with the dielectric properties from this study for comparison.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Radio-frequency exposure of the yellow fever mosquito (A. aegypti) from 2 to 240 GHz

et al. 2021

View full text Add to dashboard Cite

Fifth generation networks (5G) will be associated with a partial shift to higher carrier frequencies, including wavelengths comparable in size to insects. This may lead to higher absorption of radio frequency (RF) electromagnetic fields (EMF) by insects and could cause dielectric heating. The yellow fever mosquito (Aedes aegypti), a vector for diseases such as yellow and dengue fever, favors warm climates. Being exposed to higher frequency RF EMFs causing possible dielectric heating, could have an influence on behavior, physiology and morphology, and could be a possible factor for introduction of the species in regions where the yellow fever mosquito normally does not appear. In this study, the influence of far field RF exposure on A. aegypti was examined between 2 and 240 GHz. Using Finite Difference Time Domain (FDTD) simulations, the distribution of the electric field in and around the insect and the absorbed RF power were found for six different mosquito models (three male, three female). The 3D models were created from micro-CT scans of real mosquitoes. The dielectric properties used in the simulation were measured from a mixture of homogenized A. aegypti. For a given incident RF power, the absorption increases with increasing frequency between 2 and 90 GHz with a maximum between 90 and 240 GHz. The absorption was maximal in the region where the wavelength matches the size of the mosquito. For a same incident field strength, the power absorption by the mosquito is 16 times higher at 60 GHz than at 6 GHz. The higher absorption of RF power by future technologies can result in dielectric heating and potentially influence the biology of this mosquito.

show abstract

Section: Discussionmentioning

confidence: 99%

“… Given for insects in other studies [ 6 , 12 , 23 , 24 , 43 , 45 , 46 ] and for the yellow fever mosquito. …”

Section: Discussionmentioning

confidence: 99%

Radio-frequency exposure of the yellow fever mosquito (A. aegypti) from 2 to 240 GHz

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Temperature did not significantly affect

in non-salted samples, but there was a significant increase in

with temperature in salted samples. Higher temperature and ion concentration increase ionic conductivity, which according to Zadeh et al [ 22 ], causes an increase in dielectric dispersion, increasing the dielectric constant.…”

Section: Resultsmentioning

confidence: 99%

“…In this case, the high frequency and low salt content cause the dipole loss to become more prevalent. Dipole loss decreases with increasing temperature due to the relaxation times becoming increasingly shorter than the frequency of the applied electric field [ 19 , 22 ]. The opposing effects of temperature on dipole loss and ionic loss resulted in relatively constant values of

across the studied temperature range.…”

Section: Resultsmentioning

confidence: 99%

Combined Effect of Temperature and Oil and Salt Contents on the Variation of Dielectric Properties of a Tomato-Based Homogenate

Abea

Gou

Guárdia

et al. 2021

Foods

View full text Add to dashboard Cite

Tomato-based processed foods are a key component of modern diets, usually combined with salt and olive oil in different ratios. For the design of radiofrequency (RF) and microwave (MW) heating processes of tomato-based products, it is of importance to know how the content of both ingredients will affect their dielectric properties. Three concentrations of olive oil and salt were studied in a tomato homogenate in triplicate. The dielectric properties were measured from 10 to 3000 MHz and from 10 to 90 °C. Interaction effects were studied using a general linear model. At RF frequencies, the dielectric constant decreased with increasing temperature in samples without added salt, but this tendency was reversed in samples with added salt. The addition of salt and oil increased the frequency at which this reversion occurred. At MW frequencies, the dielectric constant decreased with increasing temperature, salt, and oil content. The loss factor increased with increasing salt content and temperature, except in samples without added salt at 2450 MHz. Penetration depth decreased with increasing frequency and loss factor. Salt and oil contents have a significant effect on the dielectric properties of tomato homogenates and must be considered for the design of dielectric heating processes.

show abstract

“…In contrast, common cultivars are less appreciated and account for approximately 20% of the production of Tunisia dates [4]. e main problem in the production, storage, marketing, and exporting of date fruits generally is the loss caused by insect infestation [5]. Particularly in Tunisia, the carob moth, Ectomyelois ceratoniae Zeller, is a major insect pest of dates, pomegranate, and several other host plants [6].…”

Section: Introductionmentioning

confidence: 99%

Freezing Treatments for Ectomyelois ceratoniae Mortality and Maintenance of Deglet Noor Palm Date Quality

Ben-Amor

Miguel-Gómez

Habib

et al. 2019

Journal of Food Quality

View full text Add to dashboard Cite

Background. Insect infestation caused by Ectomyelois ceratoniae or carob moth is one of the main postharvest problems that can lead to a decrease of the marketable quality of dates. The control of carob moth is a mandatory process for exported fruits, and the main chemical method used to prevent pest diseases of palm date is treatment with methyl bromide. However, its use is being restricted due to direct harmful effects on the environment and indirect effects on humans. Freezing treatments could be physical alternatives to methyl bromide and other chemicals. Three freezing treatments at −18°C (50 h, 77 h, and 125 h) were studied for E. ceratoniae mortality in Deglet Noor date fruits. Results. The results showed that freezing at −18°C led to 100% mortality of all the stages of E. ceratoniae found in naturally infested dates. Fruit quality was examined under a selected sanitizing freezing treatment (50 hours at −18°C). This freezing treatment induced an increase of monosaccharides and a reduction in antioxidant activity (40 to 45%, measured with FRAP and DPPH assays). However, other parameters such as color, amino acids, total phenolic content, and microbial and sensorial quality were not affected by that treatment. All samples remained above the limit of marketability as there was no chilling injury. Conclusion. This treatment can be recommended as a green alternative to chemical treatments to control carob moth while yielding optimum-quality Deglet Noor date fruits that could be exported to developed countries.

show abstract

Measuring the dielectric properties of date palm fruit, date palm leaflet, and Dubas bug at radio and microwave frequency using two-port coaxial transmission/reflection line technique

Cited by 13 publications

References 38 publications

Radio-frequency exposure of the yellow fever mosquito (A. aegypti) from 2 to 240 GHz

Radio-frequency exposure of the yellow fever mosquito (A. aegypti) from 2 to 240 GHz

Combined Effect of Temperature and Oil and Salt Contents on the Variation of Dielectric Properties of a Tomato-Based Homogenate

Freezing Treatments for Ectomyelois ceratoniae Mortality and Maintenance of Deglet Noor Palm Date Quality

Contact Info

Product

Resources

About