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1

Właściwości sorpcyjne i sensoryczne wybranych produktów dietetycznych na bazie płatków owsianych

Ruszkowska M., Józefczak A.

Ekologia i Technika

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2016

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R. 24, nr 3

134--140

EN

The aim of the study was to determine the dietetic products based on oat flakes. The materiał consisted of 3 types of oat products: the flakes of firm A wlth plum and milk (product I), the flakes of firm A with apple and cinnamon (product II) and the flakes of firm B with apple and cinnamon (product III). The work included evaluation of sorption properties and sensory test of the products. Determine the content and water activity and sorption isotherms at 20°C. The BET eąuation was calculated monolayer capacity also calculated a surface area of sorption and structure parameters of the tested materials. sensory characteristics were evaluated using point method which is designed to determine the level of ąuality of individual traits (traits) qualitative numerical value according to the adopted scale of 1 to 5. where l point - the lowest ratłng, while 5 points - the highest rating. Based on the results,it was found that the best product in terms of quality and storage stability as well as sensory properties was the product II (oatmeal with milk, apple and cinnamon).

PL

Celem przeprowadzonych badań była ocena produktów dietetycznych na bazie płatków owsianych Materiał składał się z 3 rodzajów produktów owsianych: płatki firmy A ze śliwką i z mlekiem (produkt I), płatki firmy A z jabłkami i cynamonem (produkt II) i płatki firmy B z jabłkiem i cynamonem (produkt III). Zakres pracy obejmował ocenę właściwości sorpcyjnych oraz sensorycznych badanych produktów. Oznaczono zawartość i aktywność wody oraz izotermy sorpcji w temp. 20°C. Na podstawie równania BET obliczono pojemność monowarstwy, ponadto obliczono powierzchnię właściwą sorpcji oraz parametry struktury badanych materiałów. Do oceny sensorycznej wykorzystano metodę punktową, która polegała na określeniu poziomu jakości poszczególnych cech (wyróżników) jakościowych za pomocą wartości liczbowych wg przyjętej skali punktowej od 1 do 5, gdzie l punkt - oznaczał ocenę najniższą, natomiast 5 punktów - ocenę najwyższą. Na podstawie przeprowadzonych badań stwierdzono, że najlepszym produktem pod względem jakości i trwałości przechowalniczej jak również oceny sensorycznej był produkt II (płatki owsiane z mlekiem, jabłkiem i cynamonem).

2

The Effect of Sonication on Acoustic Properties of Biogenic Ferroparticle Suspension

Józefczak A., Hornowski T., Król A., Molčan M., Leszczyński B., Timko M.

Archives of Acoustics

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2016

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Vol. 41, No. 1

161--168

EN

Superparamagnetic iron oxide nanoparticles (SPION) synthesised chemically usually need the modification of the particle surface. Other natural sources of magnetic particles are various magnetotactic bacteria. Magnetosomes isolated from magnetotactic bacteria are organelles consisting of magnetite (Fe3O4) or greigite (Fe3S4) crystals enclosed by a biological membrane. Magnetotactic bacteria produce their magnetic particles in chains. The process of isolation of magnetosome chains from the body of bacteria consists of a series of cycles of centrifugation and magnetic decantation. Using a high-energy ultrasound it is possible to break the magnetosome chains into individual nanoparticles – magnetosomes. This study presents the effect of sonication of magnetosome suspension on their acoustic properties, that is speed and attenuation of the sound. Acoustic propagation parameters are measured using ultrasonic spectroscopy based on FFT spectral analysis of the received pulses. The speed and attenuation of ultrasonic waves in magnetosome suspensions are analysed as a function of frequency, temperature, magnetic field intensity, and the angle between the direction of the wave and the direction of the field.

3

Ultradźwięki jako narzędzie badań nanomateriałów

Hornowski T., Józefczak A., Skumiel A.

Postępy Fizyki

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2013

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T. 64, z. 3-6

116--119

PL

Rozchodzeniem się fal ultradźwiękowych i słyszalnych rządzą te same prawa fizyczne, a tym, co je różni, jest przede wszystkim częstotliwość. Ta pozornie drobna różnica ma ogromne konsekwencje praktyczne. Fale sprężyste o dużych częstotliwościach dają sie łatwo kształtować w wąskie wiązki, co umożliwia ich wykorzystanie do kierunkowego sondowania właściwości ośrodka lub aktywnego wpływu na jego stan za pomocą temperatury lub nieliniowych zjawisk w rodzaju kawitacji.

4

Ultrasonic Properties of Magnetic Nanoparticles with an Additional Biocompatible Dextrane Layer

Dąbek L., Hornowski T., Józefczak A., Skumiel A.

Archives of Acoustics

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2013

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Vol. 38, No. 1

93--98

EN

The temperature dependence of the particle size distribution (PSD) of the magnetic fluid with an additional biocompatible dextran layer was studied using a ultrasonic method. The measurements of the ultrasound velocity and attenuation were carried out as a function of the volume concentration of magnetite particles at temperatures ranging from 15°C to 40°C. In order to extract the PSD from ultrasonic measurements, the theoretical model of Vinogradov-Isakovich was used. The extraction of PSD from the ultrasonic data requires also the measurements the density and viscosity of the ferrofluid samples. The calculated PSD of the magnetic fluid with an additional biocompatible layer shows a greater thermal stability than that of a magnetic fluid with a single surfactant layer.

5

Investigation of Ultrasonic Emulsifying Processes of a Linseed Oil and Water Mixture

Skumiel A., Józefczak A., Heller K., Hornowski T., Wielgusz K.

Archives of Acoustics

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2013

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Vol. 38, No. 3

297--301

EN

Ultrasonic emulsifying processes of immiscible liquids can be used to obtain stable emulsions. The authors used an ultrasonic sandwich head with an energy concentrator to obtain a suitable value of the energy density necessary for the emerge of ultrasonic cavitation. Two piezoelectric ring (Dext = 50 mm) transducers of Pz-26 type produced by FERROPERM were used to design the ultrasonic sandwich head. The frequency of the ultrasonic wave was 18.4 kHz and the excitation time of the ultrasonic transducer exiting 5 minutes. Visible bubbles during the generation of ultrasonic waves appeared in the mixture after exceeding the cavitation threshold. The authors determined also the cavitation threshold by measuring the electrical voltage conducted to the transducers. To receive long-lasting emulsion, the electrical voltage attained 300 Vpeak. The dispersion dependence on the emulsifying time was determined. The emulsion of linseed oil and water was stable through some months without surfactants.

6

Detection of structural transformations in magnetic fluids for biomedical application by ultrasound

Józefczak A.

Molecular and Quantum Acoustics

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2008

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Vol. 29

121-133

EN

Acoustic spectroscopy has been used to investigate the effect of surface-coating layers in biocompatible magnetic fluids. The method applied is sensitive to structural changes in the suspension as the ultrasonic attenuation is correlated with the concentration of particles and the particle size distribution. The structural characteristics (aggregation phenomena) of the magnetic fluids with a single and double layer of a surfactant on magnetic field sweep have been analyzed on the basis of ultrasound attenuation measured for different frequencies of the acoustic wave.

7

Detection of structural transformations in magnetic fluids for biomedical application by ultrasound

Józefczak A.

Molecular and Quantum Acoustics

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2007

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Vol. 28

137-149

EN

Acoustic spectroscopy has been used to investigate the effect of surface-coating layers in biocompatible magnetic fluids. The method applied is sensitive to structural changes in the suspension as the ultrasonic attenuation is correlated with the concentration of particles and the particle size distribution. The structural characteristics (aggregation phenomena) of the magnetic fluids with a single and double layer of a surfactant on magnetic field sweep have been analyzed on the basis of ultrasound attenuation measured for different frequencies of the acoustic wave.

8

Determination of Magnetic Particle Size Using Ultrasonic, Magnetic and Atomic Force Microscopy Methods

Zieliński B., Skumiel A., Józefczak A., Vandeweert E.

Molecular and Quantum Acoustics

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2005

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Vol. 26

309-316

9

Temperature Dependence of the Ultrasonic Wave Absorption Coefficient in Ferrofluid Subjected to External Magnetic Field

Józefczak A., Skumiel A., Regulska P.

Molecular and Quantum Acoustics

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2004

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Vol. 25

153-158

10

The Effect of Duration of Magnetic Field Application and Temperature of Velocity and Absorption Coefficient of Ultrasound Wave in a Magnetic Fluid

Hornowski T., Józefczak A., Łabowski M., Skumiel A.

Molecular and Quantum Acoustics

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2003

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Vol. 24

31-40

11

Effects of Magnetic Field Decay Time on the Hysteresis of Ultrasonic Wave Attenaution on Ferrofluid

Józefczak A., Skumiel A.

Molecular and Quantum Acoustics

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2003

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Vol. 24

89-96

EN

Acoustic properities of a ferrofluid subject to an external magnetic filed depend on the sweep rate. The magnetic filed determines the mode and degree of aggregations of the magnetic particles and their association into chain-like clusters. After the removal of the filed the ferrofluid does not return to the original state as indicated by the ultrasound wave propagation study, in particular by changes in the ultrasonic wave absorption coefficient. A hysteresis of the ultrasonic wave absorption coefficient has been observed. The hysteresis depends on the rate of the magnetic field intensity decay. The effect of the hysteresis on the acoustic properities of the ferrofluid has been studied.

12

Ultrasonic and Magnetic Study of Physiology Based Magnetic Fluid

Józefczak A., Skumiel A., Łabowski M., Timko M., Gierczyk N.

Molecular and Quantum Acoustics

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2002

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Vol. 23

193-199

13

The Effect of the Concentration of Ferroparticles in a Magnetic Fluid on its Acoustic and Magnetic Properties

Skumiel A., Józefczak A., Hornowski T., Kaczmarek M.

Molecular and Quantum Acoustics

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2002

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Vol. 23

389-396

14

Magnetic and Ulrtrasonic Studies of Gel-Like Magnetic Systems

Hornowski T., Skumiel A., Józefczak A., Kaczmarek M.

Molecular and Quantum Acoustics

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2001

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Vol. 22

107-112

EN

The paper presents results of experimental studies of magnetic susceptibility and ultrasonic properties of ferrogel in the presence of magnetic field. The results are discussed in terms of theoretical predictions, and some magnetic as well as elastic parameters of studied system are obtained.

15

Determination on the Magnetic Susceptibility Anisotropy, Propagation Velocity and Absorption Coefficient of an Ultrasonic Wave in a Magnetic Fluid

Skumiel A., Hornowski T., Józefczak A., Łabowski M.

Molecular and Quantum Acoustics

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2001

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Vol. 22

221-230

16

An Investigation of the Magnetic Properties of Ferrofluids

Skumiel A., Hornowski T., Józefczak A., Łabowski M.

Molecular and Quantum Acoustics

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2001

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Vol. 22

231-238

17

The effect of rate changes of the constant external magnetic field on the coefficient of ultrasonic wave absorption in polydispersive magnetic fluid

Józefczak A., Skumiel A., Łabowski M.

Archives of Acoustics

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2000

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Vol. 25, no. 4

441-449

EN

In this paper are presented experimental results of changes of the ultrasonic wave absorption coefficient as the function of external magnetic field intensity, for different rates of magnetic field changes in a polydispersive magnetic liquid EMG-605 based on water. Measurements were performed for two frequencies of ultrasonic wave: 3.6MHz and 6.12MHz, where the directions of propagation of ultrasonic wave and external magnetic field were mutually parallel and perpendicular. This paper presents also the radii of detected spherical clusters formed in magnetic fluid under the influence of magnetic field.

18

Acoustic and magnetic properties of magnetic fluids

Skumiel A., Hornowski T., Józefczak A.

Archives of Acoustics

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1999

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Vol. 24, no. 2

129-144

EN

The influence of magnetic field on the acoustic and magnetic properties of magnetic liquids is discussed. By fitting the curve of Taketomi's theory to the experimental data of the anisotropy of ultrasonic attenuation, the values of quantities describing the structure of magnetic liquid have been determined. Moreover, the dependence of magnetic susceptibility on frequency has been measured. It shows that two processes of magnetization, which are based on the mechanisms proposed by Brown and Néel, contribute to the magnetization of the EMG-605 magnetic liquid.

19

Wykorzystanie rezonansowego pochłaniania fali ultradźwiękowej do określania rozmiarów klasterów cieczy magnetycznej APG-832

Józefczak A., Skumiel A., Hornowski T.

Molecular and Quantum Acoustics

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1998

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Vol. 19

119-124

EN

A magnetic fluid is a colloidal suspension of magnetic particles in a liquid carrier. It uses in engineering applications. Industries most commonly use ferrofluids are computers loundspeakers, petrochemicals, semiconductors, medicals. The present paper includes results of measurement dimension of spherical which arise in a magnetic fluid under the influence an external magnetic field. We used an acoustic method of a ultrasonic wave resonanse absorbtion. The measurement have been carried out in a magnetic fluid APG-832 for frequency f=l,l MHz at the temperatures 20°C, 30°C, 40°C, 50°C and 60°C. The obtain dimensions of spherical clusters are 624 nm (100 mT) - 1324 nm (450 mT).

20

Resonance absorption of ultrasonic waves in a magnetic fluid

Skumiel A., Łabowski M., Józefczak A.

Archives of Acoustics

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1998

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Vol. 23, no. 2

195--210

EN

An external magnetic field applied to a magnetic fluid gives rise to the appearance of spherical and chain-like clusters. The present work is based on an acoustic method permitting the determination of the presence and size of the clusters by resonance absorption of an ultrasonic wave in a magnetic fluid under the influence of a magnetic field. Measurements by applying the pulse method of the variations of the ultrasonic absorption coefficient &Delta? for three frequencies in a selected magnetic fluid versus the external magnetic field strength have been reported.