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549 554 Cleary, S. F., Cao, G. H., Liu, L. M. (1996) Effect of isothermal 2.45 GHz microwave radiation on the mammalian cell cycle: comparison with effects of isothermal 27 MHz

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Abstract  

In a microwave study a program was designed for thermal regulation. This software allows different types of regulations: P, PI, PD or PID (proportional integration derivation). Results obtained with PID and PI regulation for different previous linear heating schedules (1 deg·s−1 and 0.15 deg·s−1) imposed on a polymer sample (DGEBA/3DCM) up to 280°C and more are reported. Mathematical resolution of thermal laws applied to the sample permits the regulation constants (T i,T d andG s) to be linked to the physical features of the polymer. A method used to calculate: the reflexion constant of the wave on the polymer, ρ and the diminution factor, α is presented.

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Radiofrequency radiations (RFR) are electromagnetic frequencies (EMFs) that encompass frequencies below that of visible light and above that of extremely low frequency fields. Typical man-made sources of RFR include broadcast AM/FM/TV, mobile phones and base stations, microwave ovens and radar. In this investigation, the cytological and molecular effects of RF-EMFs at 2.45 GHz, the frequency commonly used in telecommunication and microwave ovens, have been investigated in dividing root cells of five wheat cultivars following grain exposure to very short times ranging from one second to one minute. Enhanced mitotic activity and increased proportion of chromosomal abnormalities were scored in root cells as the exposure time increased. Most abnormalities are comprised of cmetaphase configurations, unoriented chromosomes at metaphase, laggards and multipolar ana-telophases indicating an action on the mitotic apparatus as well as chromosomal bridges and the formation of micronuclei indicating true clastogenic effects by the used radiation. In addition, the amplified fragment length polymorphism (AFLP) fingerprinting indicated marked DNA polymorphism among wheat cultivars and also as a result of exposure to RF-EMFs at 2.45 GHz. The results indicate remarkable cytogenetic and molecular consequence of man-made sources of RFR in plants that may lead to genetic variation. However, further research on this aspect is required to get a concrete answer for its mutagenic/carcinogenic activity.

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Acta Alimentaria
Authors:
V. Kapcsándi
,
A.J. Kovács
,
M. Neményi
, and
E. Lakatos

The aim of our experiments was to demonstrate the non-thermal effect of microwave treatment on Saccharomyces cerevisiae fermentation activity. A method was developed for studying the effects of various treatments in the course of must fermentation. The raw material (must) was treated in different ways: (i) heat transfer; (ii) microwave treatment; (iii) inoculation with yeast, and (iv) their combinations. The results of the treatments were compared with respect to alcohol concentration, sugar content, and acidity. The results proved that sugar content of the treated samples rapidly decreased compared to the control sample, and fermentation time was 40% shorter in the fastest case. These results can be explained by the yeast inoculation and microwave treatment. Due to non-thermal effects, fermentation capacity increased by about 30%, while the energy consumption decreased.

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The present paper concretizes one of the principal positions of Kozyrev’s (1908–1983) theory of time.

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The evaporation of a polar liquid at low pressure and exposed to microwave radiation has been investigated, as an example of an endothermic reaction. A fixed, high column of liquid was irradiated in a waveguide with 2.45 MHz-CW microwave radiation. The temperatures of the gas and the liquid in contact with the interface and the evaporation rate were measured as functions of the non-equilibrium gas pressure and the microwave field.

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Journal of Thermal Analysis and Calorimetry
Authors:
G. Roussy
,
P. Colin
,
J. Thiebaut
,
G. Bertrand
, and
G. Watelle

The evaporation of a polar liquid at low pressure upon exposure to microwave radiation has been investigated. The conventional theories previously developed to describe the non-equilibrium conditions of the evaporating interface are found to be in poor agreement with the experimental results. It is possible to take into account the influence of microwave fields on the evaporating surface by modifying the expression for the entropy production. Another approach, based on the concept that microwaves would increase the pressure, has also been found to be satisfactory.

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The paper discusses a possibility to grow seeds on solutions of microelements and application of sprouts enriched in such a way as an alternative to commercial dietary supplements. It contains a short review of the approaches reported till now and a systematic experimental study, carried on the most frequently used seeds (Lens culinaris, Helianthus annuus, Vigna radiata, Glycine max, and Lepidium sativum).Seven metals (Fe, Cu, Zn, Ni, Co, Cd, and Mn) were studied. Seeds were grown on cellulose in 20°C temperature using deionized water enriched with metals in concentrations: 100, 50, 25, 12.5, 6.25, and 3.125 mg/L in a period of 4 days. The reference samples were the seeds grown on pure deionized water. Sprouts were mineralized by microwave radiation, and the metal content was quantified by ion chromatography with on-line post-column derivatization and spectrophotometric detection.The conclusions can be treated as general recommendations, which seeds should be grown and what concentrations of metals in solutions should be applied to provide good enrichment and to avoid risk of microelement overdose.

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Schmutz, P., Siegenthaler, J., Stager, C., Tarjan, D., Bucher, J. B. (1996) Long-term exposure of young spruce and beech trees to 2450-MHz microwave radiation. Sci. Tot. Environ. 180, 43

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Mekki, L., Badr, A. (2013) Cytological and molecular consequences of wheat grain exposure to microwave radiations. Acta Bot. Hung. 55 , 61–79. Badr A Cytological and molecular

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