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1
Content available remote Strain examinations of the left ventricle phantom by ultrasound and multislices computed tomography imaging
Trawiński Z., Wójcik J., Nowicki A., Olszewski R., Balcerzak A., Frankowska E., Zegadło A., Rydzyński P.
Biocybernetics and Biomedical Engineering
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2015
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Vol. 35, no. 4
255--263
EN
The main aim of this study was to verify the suitability of the hydrogel sonographic model of the left ventricle (LV) in the computed tomography (CT) environment and echocardiography and compare the radial strain calculations obtained by two different techniques: the speckle tracking ultrasonography and the multislices computed tomography (MSCT). The measurement setup consists of the LV model immersed in a cylindrical tank filled with water, hydraulic pump, the ultrasound scanner, hydraulic pump controller, pressure measurement system of water inside the LV model, and iMac workstation. The phantom was scanned using a 3.5 MHz Artida Toshiba ultrasound scanner unit at two angle positions: 0° and 25°. In this work a new method of assessment of RF speckles' tracking. LV phantom was also examined using the CT 750 HD 64-slice MSCT machine (GE Healthcare). The results showed that the radial strain (RS) was independent on the insonifying angle or the pump rate. The results showed a very good agreement, at the level of 0.9%, in the radial strain assessment between the ultrasound M-mode technique and multislice CT examination. The study indicates the usefulness of the ultrasonographic LV model in the CT technique. The presented ultrasonographic LV phantom may be used to analyze left ventricle wall strains in physiological as well as pathological conditions. CT, ultrasound M-mode techniques, and author's speckle tracking algorithm, can be used as reference methods in conducting comparative studies using ultrasound scanners of various manufacturers.
2
Content available Group and Phase Velocity of Love Waves Propagating in Elastic Functionally Graded Materials
Kiełczyński P., Szalewski M., Balcerzak A., Wieja K.
Archives of Acoustics
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2015
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Vol. 40, No. 2
273--281
EN
This paper presents a theoretical study of the propagation behaviour of surface Love waves in nonhomogeneous functionally graded elastic materials, which is a vital problem in acoustics. The elastic properties (shear modulus) of a semi-infinite elastic half-space vary monotonically with the depth (distance from the surface of the material). Two Love wave waveguide structures are analyzed: 1) a nonhomogeneous elastic surface layer deposited on a homogeneous elastic substrate, and 2) a semi-infinite nonhomogeneous elastic half-space. The Direct Sturm-Liouville Problem that describes the propagation of Love waves in nonhomogeneous elastic functionally graded materials is formulated and solved 1) analytically in the case of the step profile, exponential profile and 1cosh2 type profile, and 2) numerically in the case of the power type profiles (i.e. linear and quadratic), by using two numerical methods: i.e. a) Finite Difference Method, and b) Haskell-Thompson Transfer Matrix Method. The dispersion curves of phase and group velocity of surface Love waves in inhomogeneous elastic graded materials are evaluated. The integral formula for the group velocity of Love waves in nonhomogeneous elastic graded materials has been established. The results obtained in this paper can give a deeper insight into the nature of Love waves propagation in elastic nonhomogeneous functionally graded materials.
3
Content available Assessment of left ventricle phantom wall compressibility by ultrasound and computed tomography methods
Trawiński Z., Wójcik J., Nowicki A., Balcerzak A., Olszewski R., Frankowska E., Zegadło A., Rydzyński P.
Hydroacoustics
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2014
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Vol. 17
211--218
EN
The present work concerns the sonographic model of the left ventricle (LV) examined in the Computed Tomography (CT) environment and compare radial strain calculations obtained by two different techniques: the speckle tracking ultrasonography and the Multislices Computed Tomography (MSCT). The Left Ventricular (LF) phantom was fabricate from 10% solution of the poly(vinyl alcohol) (PVA). Our model of the LV was driven by the computer-controlled hydraulic piston Super-Pump (Vivitro Inc., Canada) with adjustable fluid volumes. The stroke volume was set at of 24ml. The fluid pressure was changed within range of 0-60 mmHg, and the pulse rate was of 60 cycles/per minute. The relationships between computer controlled left ventricular wall deformations and its visualizations of the echocardiographic and CT imaging, both in the normal and pathological conditions were examined. The difference of assessment the Radial Strain between two methods was not exceeding 1.1%.
4
Content available remote Thermodynamic Method for Measuring the B/A Nonlinear Parameter Under High Pressure
Kiełczyński P., Szalewski M., Balcerzak A., Wieja K., Rostocki A., Siegoczyński R.
Engineering Transactions
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2014
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Vol. 62, iss. 1
5--15
EN
The nonlinearity parameter B/A is a measure of the nonlinearity of the equation of state for a fluid. The nonlinearity parameter B/A is a physical parameter often used in acoustics, from underwater acoustics to biology and medicine. It can provide information about structural properties of the medium, internal pressure and inter-molecular spacing. The thermodynamic method has been applied for determination of B/A parameter in diacylglycerol (DAG) oil as a function of pressure at various temperatures. Isotherms of the density and phase velocity of longitudinal ultrasonic wave as a function of pressure have been measured. Using the thermodynamic method along with measured isotherms of sound speed and density, the nonlinearity parameter B/A (for DAG oil) was evaluated as a function of pressure (up to 220 MPa) at various temperatures ranging from 20 to 50◦C.
5
Content available remote A New Nanoporous Material in Chemical Sensor for Vapors of Some Volatile Organic Solvents
Balcerzak A.
Archives of Metallurgy and Materials
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2009
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Vol. 54, iss. 4
999-1004
EN
A new material has been proposed as a chemosensitive layer in the surface acoustic wave sensor for vapors of some volatile organic solvents. This material has been fabricated from the bicomponent mixture of 5-[[1,3-dioxo-3-[4-(1-oxooctadecyl) phenyl] propyl] amino]-1,3-benzenedicarboxylic acid and cetylamine. In the Langmuir-Blodgett process a nanolayer of the mixture has been deposited on a piezoelectric substrate with interdigital transducers. Subsequently, the molecules of cetylamine have been removed from the layer leaving nanopores. Sensing properties of this layer for the vapors of some volatile organic solvents in air have been investigated.
PL
Zaproponowano nowy materiał na warstwę chemoczułą czujnika do wykrywania par wybranych lotnych rozpuszczalników organicznych, wykorzystującego akustyczną falę powierzchniową. Materiał ten został wytworzony z dwuskładnikowej mieszaniny kwasu 5-[[1,3-diokso-3-[4-(1-oksooktadecylo) fenylo] propyl] amino]-1,3-benzenodikarboksylowego i cetyloaminy. Osadzono nanowarstwę tej mieszaniny na podłożu piezoelektrycznym z przetwornikami międzypalczastymi stosując proces Langmuira-Blodgett. Następnie cząsteczki cetyloaminy zostały usunięte z warstwy pozostawiajac po sobie nanopory. Zbadano wrażliwość tej warstwy na pary wybranych lotnych rozpuszczalników organicznych w powietrzu.
6
Content available remote Adsorption properties of porous Langmuir-Blodgett layer used in SAW sensor for vapors of some chlorinated hydrocarbons
Balcerzak A.
Archives of Acoustics
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2009
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Vol. 34, No. 3
345-352
EN
The porous Langmuir-Blodgett film has been fabricated from an equimolar mixture of 5-[[1,3-dioxo-3- [4- (1-oxooctadecyl) phenyl] propyl] amino] - 1,3 - benzenedicarboxylic acid (DA) with cetylamine (CA) and subsequently removing of cetylamine after a layer deposition. This film has been investigated as the sensing layer of the surface acoustic waves (SAW) sensor of vapors of some chlorinated hydrocarbons in air. From the experimental results the values of the number of adsorbed molecules of chlorinated hydrocarbons per surface of sensing layer, NM/A, for this porous Langmuir-Blodgett layer has been calculated. An attempt to explain the observed differences in the adsorption of chlorinated hydrocarbons has been undertaken.
7
Content available remote Ultrasonic measurements of aqueous solutions of ?-cyclodextrin with alkyl pyridinium bromides
Balcerzak A.
Archives of Acoustics
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2008
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Vol. 33, No. 4
627-641
EN
Ultrasonic measurements of the velocity and absorption coefficient, α/f2, of aqueous solutions of β-cyclodextrin with alkyl pyridinium bromides CnH2n+1C5H4NBr (n = 8, 10, 12), were carried out at the following temperatures: 288.2 K, 298.2 K, 308.2 K and 318.2 K, and frequency range from 1 MHz to 150 MHz. Concentration of the both components equaled 0.01 M. The occurrence of two ultrasonic relaxation processes has been reported. Thermodynamic and kinetic parameters related to these processes have been calculated. The obtained results have been compared with data published previously for α-cyclodextrin systems.
8
Ultrasonic chemical sensor for detection of vapors of some volatile organic compounds
Balcerzak A., Zhavnerko G.
Molecular and Quantum Acoustics
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2007
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Vol. 28
7-12
EN
The reaction of the organic monomolecular Langmuir-Blodgett layer, deposited on the sensor delay line using surface acoustic wave, on the presence of vapors of some volatile organic compounds from groups of aliphatic and aromatic hydrocarbons, in air has been investigated. The chemical composition of this layer is an equimolar mixture of 5-[[1,3-dioxo-3- [4- (1-oxooctadecyl) phenyl] propyl] amino] – 1,3 – benzenedicarboxylic acid (DA) and cetylamine (CA). Time of sensor reaction is less than 2 seconds. The reaction of the sensor on the hydrocarbon vapors in air is reversible. Decrease of the differential frequency after contact with the vapor-air mixture and decrease of this frequency in time are different for various hydrocarbons; a length of the chain is important for aliphatic hydrocarbons and a presence or not of side chains – for aromatic ones.
9
Langmuir-blodgett layer as chemosensitive element of ultrasonic chemical sensor
Balcerzak A., Zhavnerko G.
Molecular and Quantum Acoustics
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2006
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Vol. 27
17-24
EN
The Langmuir-Blodgett layer deposited on one channel of the bi-channel sensor delay line is proposed as chemosensitive element of a ultrasonic chemical sensor. Chemical composition of this layer is an equimolar mixture of 5-[[1,3-dioxo-3- [4- (1-oxooctadecyl) phenyl] propyl] amino] - 1,3 - benzenedicarboxylic acid (DA) and cetylamine (CA). The thickness of this layer is equal to dimension of one molecule. The chemical sensitivity of this layer to some mixtures of air with vapor of volatile organic compounds has been investigated.
10
Relaxation Phenomena In The Nematic Phase of Liquid Crystal Near Phase Transition
Balcerzak A.
Molecular and Quantum Acoustics
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2005
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Vol. 26
7-13
EN
Absorption of ultrasonic longitudinal waves in the nematic liquid crystal 1-(trans- 4-hexylcyclohexyl)-4-isothiocyanatobenzene (6CHBT) was measured in the temperature (24-56oC) and frequency (3.2-100 MHz) ranges. In the region of the phase transition the anomalous absorption has been observed. This absorption rapidly increases when the frequency of the ultrasonic wave decreases. The experimental results for the nematic phase were analysed and two relaxation processes have been found. Relaxation parameters for both processes were calculated. The process with the longer relaxation time is connected with the order parameter changes. The isomeric changes in the hexyl chain of the 6CHBT molecule is the origin of the process characterized by the shorter relaxation time.
11
Content available remote Ultrasonic measurements in the 1-(trans-4-hexylcyclohexyl)-4-isothiocyanatobenzene near the nematic-isotropic transition
Balcerzak A.
Archives of Acoustics
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2005
|
Vol. 30, No. 3
373-378
EN
The absorption and velocity of ultrasonic longitudinal waves in the nematic liquid crystal 1-(trans-4-hexylcyclohexyl)-4-isothiocyanatobenzene (6CHBT) have been measured as a function of temperature between 24°C and 55°C at 5.2 MHz. The temperature dependence of ultrasonic absorption has a sharp maximum, whereas that dependence of velocity shows a local minimum in the region of the nematic-isotropic (N-I) phase transition. Additional temperature measurements of density have been done to calculate the thermal coefficient of expansion and the temperature coefficient of adiabatic compressibility. Both these parameters exhibit critical behaviour at the transition which has been analysed. The values of the exponent determining the growth of the order fluctuations have been calculated and compared with references.
12
Results of Ultrasonic Velocity and Density Investigations of the Nematic Liquid Crystal
Balcerzak A.
Molecular and Quantum Acoustics
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2004
|
Vol. 25
17-22
EN
Velocity of ultrasonic longitudinal waves in the nematic liquid crystal 1-(trans-4- hexylcyclohexyl)-4-isothiocyanatobenzene (6CHBT) has been measured as a function of temperature between 24oC and 55oC at 5.2 MHz. The temperature dependence of velocity shows a local minimum in the region of the nematicisotropic (N-I) phase transition. Additional temperature measurements of density have been done to calculate the thermal coefficient of expansion and the temperature coefficient of adiabatic compressibility. Both these parameters exhibit critical behaviour at the transition which has been analysed. The values of the exponent determining the growth of the order fluctuations have been calculated and compared with references.
13
Content available remote Ultrasonic investigations of inclusion complexes of cyclodextrins with amphiphilic substances - further results and conclusions
Balcerzak A.
Archives of Acoustics
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2004
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Vol. 29, no. 3
461-466
EN
On the basis of formerly made and published [1-3] ultrasonic measurements of aqueous solutions of ?- or ß-cyclodextrin with amphiphilic substances, calculations have been done and new conclusions drawn. These calculations and conclusions explain some experimental results concerning the stability of inclusion complexes of cyclodextrin with amphiphilic substances and the mechanism of the formation of such complexes.
14
Some Results of Ultrasonic Spectroscopy Invastigations of Aqueous Systems of Cyclodexrtins and Amphiphilic Substances
Balcerzak A.
Molecular and Quantum Acoustics
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2003
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Vol. 24
9-15
EN
On basis of formerly made and published [1-4] ulrtasonic spectroscopy measurements of aqueous systems of a- or B-cyclodextrin with amphiphilic substances, calculations explain some wxperimental results concerning stability of inclusion coplexes of the cyclodextrin and the amphiphilic substance and a mechanism of these complexes formation. Simple geometric considerations and the three-step kinetic mechanism have been applied.
15
Urządzenia do ograniczania przepięć w sieciach rozdzielczych niskiego napięcia - interpretacja kontrowersyjnych pojęć i definicji oraz zasady doboru parametrów technicznych do warunków pracy w sieci
Balcerzak A.
Wiadomości Elektrotechniczne
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2002
|
R. LXX, nr 3
82-86
PL
Omówiono parametry urządzeń ochronnych oraz związane z nimi podstawowe pojęcia i definicje pojawiające się w różnych dokumentach normalizacyjnych. Podano zasady wyboru parametrów technicznych urządzeń do ograniczania przepięć, w zależności od przewidywanych warunków pracy w sieci.
EN
Discussion of the parameters of the protective equipment and the relevant concepts and definitions appearing in various standardizing documents. Principles of selection of the technical parameters of the equipment used for reducing overvoltages depending on the expected operation condition in a network.
16
Absorption of Ultrasonic Waves in Aqueous Binary Mixtures of alfa-Cyclodextrin and Some Amphiphilic Substances
Balcerzak A., Płowiec R., Kiełczyński P., Juszkiewicz A.
Molecular and Quantum Acoustics
|
2002
|
Vol. 23
15-25
17
Urządzenia do ograniczania przepięć w sieciach rozdzielczych niskiego napięcia. Interpretacja kontrowersyjnych pojęć i definicji. Zasady doboru parametrów technicznych do warunków pracy w sieci
Balcerzak A.
Energetyka
|
2002
|
nr 3
127-130
18
Content available remote Ultrasonic investigations of aqueus solutions of α-cyclodextrin and amphiphil substances having different "heads" and identic "tails"
Balcerzak A., Płowiec R., Kiełczyński P., Juszkiewicz A.
Archives of Acoustics
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2002
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Vol. 27, no. 4
361-371
EN
Velocity and absorption of ultrasonic waves in aqueuos solutions of a-cyclodextrin containing amphiphil substances with different ``heads" and identic ``tails" were carried out. As a result of the mutual interactions between a-cyclodextrin and the amphiphil substance the low frequency ultrasonic relaxation process has been established. Thermodynamic and kinetic parameters related to this process have been calculated. Obtained results have been discussed considering molecular structure of the amphiphil substances.
19
Content available remote Investigations of ultrasonic velocity and absorption in aqueous solutions of [alpha]- and ß-cyclodextrin with sodium alkyl sulfates. Part 2. ß-cyclodextrin systems
Balcerzak A., Płowiec R., Juszkiewicz A.
Archives of Acoustics
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2001
|
Vol. 26, no. 1
51-63
EN
In second part of this work, velocity and absorption measurements of ultrasonic waves in aqueous solutions of ß-cyclodextrin containing different sodium alkyl sulfates are reported. One or two relaxation processes for these solutions have been established. Thermodynamic and kinetic parameters related to these processes have been calculated. The results have been compared with those obtained for solutions of ?-cyclodextrin and presented in Part 1 of this paper. Explanation of the origins of these processes has been proposed.
20
Content available remote Investigations of ultrasonic velocity and absorption in aqueous solutions of [alpha]- and ß-cyclodextrin with sodium alkyl sulfates. Part 1. [alpha]-cyclodextrin systems
Balcerzak A., Płowiec R., Juszkiewicz A.
Archives of Acoustics
|
2001
|
Vol. 26, no. 1
37-52
EN
In this part, the velocity and absorption measurements of ultrasonic waves in aqueous solutions of [alpha]-cyclodextrin containing different sodium alkyl sulfates are reported. One or two relaxation processes for these solutions have been established. Thermodynamic and kinetic parameters related to these processes have been calculated. In the second part, experimental results for ß-cyclodextrin will be reported and compared with those presented here.
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