The use of the high-frequency electromagnetic field (MW) and of the pulsed electric field (PEF) for the extraction of bioactive compounds from grapes

Author(s):  
Alin Cristian Teusdea ◽  
Simona Vicas ◽  
Livia Bandici ◽  
Gheorghe Emil Bandici
2002 ◽  
Vol 34 (1) ◽  
pp. 101-108
Author(s):  
Pantelija Nikolic ◽  
S. Djuric ◽  
K. Radulovic ◽  
D. Vasiljevic-Radovic ◽  
M.V. Nikolic ◽  
...  

The possibility of characterization of aluminium powders using a horizontal coherer has been considered. Al powders of known dimension were treated with a high frequency electromagnetic field or with a DC electric field, which were increased until a dielectric breakdown occurred. Using a multifunctional card PC-428 Electronic Design and a suitable interface between the coherer and PC, the activation time of the coherer was measured as a function of powder dimension and the distance between the coherer electrodes. It was also shown that the average dimension of powders of unknown size could be determined using the coherer.


2016 ◽  
Vol 695 ◽  
pp. 289-294
Author(s):  
Livia Bandici ◽  
Simona Ioana Vicas ◽  
Gheorghe Emil Bandici ◽  
Alin Cristian Teusdea ◽  
Simona Cavalu

In this paper, grapes were processed by using high frequency electromagnetic field in order to obtain a high quality wine in terms of bioactive compounds content with antioxidant activity. The experimental setup comprise an applicator with adjustable power between 100-1000 W, software assisted, in order to process three varieties of grapes (Muscat Ottonel, Merlot, Pinot Noir), that were harvested in 2014 in the Crişana-Sântimreu vineyard. The total polyphenol compounds were measured using the Folin-Ciocalteu spectrophotometric method, and the antioxidant capacity was determined by the FRAP method. The results have shown that the use of high frequency electromagnetic field in grape processing leads to the diffusion of the bioactive compounds with antioxidant activity in the final product. In the same time, it is also an effective method in terms of energy consumption.


2020 ◽  
Vol 39 (1) ◽  
pp. 368-376
Author(s):  
Xingjuan Wang ◽  
Hebin Jin ◽  
Liguang Zhu ◽  
Ran Liu ◽  
Tushun Song

AbstractSoft-contact of molten steel can be achieved by applying a high-frequency electromagnetic field above the mold of continuous casting, which can effectively eliminate surface defects and achieve billets with no cracks and no oscillation marks. It also has some influence on the mold flux. In this study, the effect of a high-frequency electromagnetic field (20 kHz) on a mold flux flow field was simulated using a finite element software, and the slag film was extracted using a slag film simulator. The effect of the high-frequency magnetic field on the microstructure of the mold flux was analyzed using X-ray diffraction, Raman spectroscopy, and mineral phase testing. The results show that the high-frequency electromagnetic field disrupts the orderly movement and increases the movement rate of the liquid flux. The precipitate phase of the slag film did not change, but the silicate dimer Q1 decreased, the chain Q2 increased, and the network degree was increased. The slag film structure changed from the original two-layer form of crystalline layer–glass layer into a three-layer form of crystal layer–glass layer–crystal, and the crystallization ratio increased by 35% on average. The grain-size melilite granularity was reduced from the original 0.12 to 0.005 mm.


Author(s):  
О. М. Петровський

Розглянуті питання передпосівної стимуляції на-сіння високочастотним електромагнітним полем.Запропоновано спосіб опромінення насіння і визна-чення його електричних характеристик. На основібудови клітин визначені електричні властивості біо-логічної тканини, з якої складається насіння. Пока-зана зміна складових активного опору в залежностівід частоти струму. Експериментально доведено,що еквівалентну електричну схему неможливо звес-ти до простих випадків з’єднання опорів і ємностей,а саме насіння не можна вважати нейтральнимдіелектриком. Розроблена методика оцінки інтенси-вності обмінних процесів залежно від електричногоопору насіння. The questions of stimulation of seed before sowing are considered by the high-frequency electromagnetic field considered. The method of irradiation of seed and determination of him is offered electric descriptions. On the basis of structure of cages electric properties of biological fabric which seed consist of are certain. The change of constituents of active resistance is shown depending on frequency of current. It is experimentally proved that it is impossible to erect an equivalent electric chart to the simple cases of connection of resistances and capacities, namely seed can not be considered a neutral dielectric. The method of estimation of intensity of exchange processes  is developed depending on electric resistance of seed.


RSC Advances ◽  
2021 ◽  
Vol 11 (50) ◽  
pp. 31408-31420
Author(s):  
Palalle G. Tharushi Perera ◽  
Nevena Todorova ◽  
Zoltan Vilagosh ◽  
Olha Bazaka ◽  
The Hong Phong Nguyen ◽  
...  

Membrane model systems capable of mimicking live cell membranes were used for the first time in studying the effects arising from electromagnetic fields (EMFs) of 18 GHz where membrane permeability was observed following exposure.


Sign in / Sign up

Export Citation Format

Share Document