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1

Algorithm for Computationally Efficient Imaging of Sound Speed in Conventional Ultrasound Sonography

Karwat Piotr

Archives of Acoustics

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2023

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Vol. 48, No. 4

549--558,

EN

The speed of sound (SoS) in tissues reflects their mechanical properties and therefore can carry valuable diagnostic information. In conventional ultrasound sonography (US), however, this information is not readily available. Furthermore, since the actual SoS is unknown, image reconstruction is carried out using an average SoS value for soft tissues. The resulting local deviations from the actual SoS lead to aberrations in US images. Methods for SoS imaging in US therefore have the potential to enable the correction of aberrations in classical US. In addition, they could also become a new US modality. There are several approaches to SoS image reconstruction. They differ in terms of input data requirements, computational complexity, imaging quality, and the potential for signal analysis at the intermediate stages of processing. This article presents an algorithm with multi-stage processing and low computational complexity. The algorithm was verified through numerical simulations and phantom measurements. The obtained results show that it can correctly estimate SoS in layered media, which in most cases model the tissue structure well. With its computational complexity of O(n), the algorithm can be implemented in real-time ultrasound imaging systems with limited hardware performance, such as portable ultrasound devices.

2

Are the Heat Capacities of Liquids Calculated from Speeds of Sound and pρT Relationships Reliable? A Comparison with the Reference Values and a Discussion of the Uncertainties

Szpaczek Sylwia, Marczak Wojciech

Archives of Acoustics

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2022

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Vol. 47, No. 4

547--554

EN

Recent advances in the construction of speed of sound meters made high-accuracy routine measurements possible in laboratories non-specialized in physical acoustics. Reliable values of the isentropic compressibility can be obtained from speeds of sound and densities of liquids using the Laplace formula. Strict thermodynamic relationships connect the isentropic compressibility of a medium and its density as a function of temperature and pressure with the heat capacity. These relationships result from the principles of thermodynamics and require no approximations or molecular models. In this study, the heat capacities of twelve liquids: hydrocarbons, acetonitrile, and ionic liquids were calculated from the speeds and densities taken from the literature sources. The agreement of the calculation results with the reference heat capacities, either critical values or measured calorimetrically, was satisfactory. The relative uncertainty of the calculated heat capacities was rather conservatively estimated for 5%. If the measurement procedures were optimized for heat capacity determination, better results would be attained, with the uncertainty probably smaller than 1%. Thus, the speed-and-density method is a potential alternative to classical calorimetry.

3

Application of Ultrasonic Methods for Evaluation of High-Pressure Physicochemical Parameters of Liquids

Kiełczyński Piotr, Ptasznik Stanisław, Szalewski Marek, Balcerzak Andrzej, Wieja Krzysztof, Rostocki Aleksander J.

Archives of Acoustics

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2019

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Vol. 44, No. 2

329--337

EN

An emerging ultrasonic technology aims to control high-pressure industrial processes that use liquids at pressures up to 800 MPa. To control these processes it is necessary to know precisely physicochemical properties of the processed liquid (e.g., Camelina sativa oil) in the high-pressure range. In recent years, Camelina sativa oil gained a significant interest in food and biofuel industries. Unfortunately, only a very few data characterizing the high-pressure behavior of Camelina sativa oil is available. The aim of this paper is to investigate high pressure physicochemical properties of liquids on the example of Camelina sativa oil, using efficient ultrasonic techniques, i.e., speed of sound measurements supported by paralel measurements of density. It is worth noting that conventional low-pressure methods of measuring physicochemical properties of liquids fail at high pressures. The time of flight (TOF) between the two selected ultrasonic impulses was evaluated with a cross-correlation method. TOF measurements enabled for determination of the speed of sound with very high precision (of the order of picoseconds). Ultrasonic velocity and density measurements were performed for pressures 0.1-660 MPa, and temperatures 3-30°C. Isotherms of acoustic impedance Za, surface tension σ and thermal conductivity k were subsequently evaluated. These physicochemical parameters of Camelina sativa oil are mainly influenced by changes in the pressure p, i.e., they increase about two times when the pressure increases from atmospheric pressure (0.1 MPa) to 660 MPa at 30°C. The results obtained in this study are novel and can be applied in food, and chemical industries.

4

An Improved Approximation for DIPPR-Based Predicting Speed of Sound in Long-Chained n-Alkanes

Postnikov E. B., Nedyalkov Y. V., Polishuk I.

Archives of Acoustics

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2018

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Vol. 43, No. 3

537--541

EN

In this short communication, we revise a correlation for the saturated liquid isothermal compressibility based on the data available in DIPPR (Postnikov, 2016) which considers the molecular non-sphericity and addresses a problem of predicting speeds of sound in saturated long-chained alkanes. In addition, we correct a misprint appeared in the cited work and provide programming code used for the realisation of the proposed calculations.

5

New instrument for measuring the velocity of sound in gases and quantitative characterization of binary gas mixtures

Koturbash T., Bicz A., Bicz W.

Measurement Automation Monitoring

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2016

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Vol. 62, No. 8

254--258

EN

A new instrument for precise measurements of velocity of sound in gases was developed and tested. The instrument implements improved velocity of sound measuring technique based on time-of-flight measurement of ultrasonic pulses. The instrument was developed primarily for conducting measurements in natural gas, it can operate in wide ranges of natural gas compositions as well as other gas mixtures with velocity of sound parameter in range of 200 to 500 m/s. The instrument allows conducting measurement of velocity of sound propagation in various gas mixtures with average repeatability of equal to ±1 cm/s at normal conditions. The accuracy of measurement depends on calibration conditions and approach, and has good agreement with theoretically calculated values. The instrument has a modular design of control unit and flow-through measuring chamber. The set of distinctive features and adjustable measuring parameters of the instrument allows further improving of applicability for other gases and gas mixtures and various measurement conditions. The instrument showed good performance in the task of quantitative characterization of binary gas mixtures by velocity of sound parameter.

6

Relationships between acoustical properties and stiffness of soft tissue phantoms

Gambin B., Kruglenko E., Byra M.

Hydroacoustics

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2016

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Vol. 19

111--120

EN

Polyvinyl-alcohol cryogel is commonly used for soft tissue phantom manufacture. The gel formation from an aqueous solution of polyvinyl-alcohol takes place during the freezing and thawing cycle. The aim of this work was to assess the degree of gel solidification, hence the material stiffness, by means of quantitative ultrasound. We manufactured three phantoms which differed in the number of freezing/thawing cycles. First, tissue phantoms were examined with an elastography technique. Next, we measured the speed of sound and the attenuation coefficient. What is more, the inter structure variations in phantoms were assessed with the Nakagami imaging which quantifies the scattering properties of the backscattered ultrasound echo. Obtained results confirmed the connection between the number of freezing/thawing cycles and the solidification p rocess. We d efined th e bo undary layer as a region which has a different structure than the sample interior. Next, for each phantom this layer was extracted based on a Nakagami parameter map. We calculated that the thickness of the boundary layer was lower in samples which were subjected to a larger number of freezing/thawing cycles.

7

Can DIPPR Database be Used for an Estimation of the Speed of Sound? A Case Study of Liquid Hydrocarbons

Postnikov E. B.

Archives of Acoustics

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2016

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Vol. 41, No. 4

713--719

EN

The paper analyses a possibility of utilising the information which is contained in DIPPR database for a calculation of the speed of sound, which is absent there. As an example, liquid hydrocarbons are considered: n-hexane, 1-hexene, cyclohexane, cyclohexene, benzene, and 1-hexanols, as well as representatives of n-alkanes with various hydrocarbon chain lengths. It is shown that the Brelvi-O’Connell correlation for the reduced bulk modulus, supplied with the correlations for the internal pressure at the normal boiling temperature, results in the values having accuracy comparable with other DIPPR data for the region below the boiling point bounded by the values of the reduced density around pr ≈ 3.5. The source of errors originated from the Brelvi-O’Connell correlation for larger reduced densities is discussed.

8

Acoustic Nonlinearity Parameter B/A, Internal Pressure, and Acoustic Impedance Determined at Pressures up to 100 MPa for 1-Ethyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide

Zorębski E., Zorębski M., Dzida M.

Archives of Acoustics

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2016

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Vol. 41, No. 1

59--66

EN

The nonlinearity parameter B/A, internal pressure, and acoustic impedance are calculated for a room temperature ionic liquid, i.e. for 1-ethyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl] imide for temperatures from (288.15 to 318.15) K and pressures up to 100 MPa. The B/A calculations are made by means of a thermodynamic method. The decrease of B/A values with the increasing pressure is observed. At the same time B/A is temperature independent in the range studied. The results are compared with corresponding data for organic molecular liquids. The isotherms of internal pressure cross at pressure in the vicinity of 70 MPa, i.e. in this range the internal pressure is temperature independent.

9

Amorphous Dielectric Thin Films with Extremely Low Mechanical Loss

Liu X., Queen D. R., Metcalf T. H., Karel J. E., Hallman F.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 1

359--363

EN

The ubiquitous low-energy excitations are one of the universal phenomena of amorphous solids. These excitations dominate the acoustic, dielectric, and thermal properties of structurally disordered solids. One exception has been a type of hydrogenated amorphous silicon (α-Si:H) with 1 at.% H. Using low temperature elastic and thermal measurements of electron-beam evap-orated amorphous silicon (α-Si), we show that TLS can be eliminated in this system as the films become denser and more structurally ordered under certain deposition conditions. Our results demonstrate that TLS are not intrinsic to the glassy state but instead reside in low density regions of the amorphous network. This work obviates the role hydrogen was previously thought to play in removing TLS in α-Si:H and favors an ideal four-fold covalently bonded amorphous structure as the cause for the disappearance of TLS. Our result supports the notion that α-Si can be made a “perfect glass” with “crystal-like” properties, thus offering an encouraging opportunity to use it as a simple crystal dielectric alternative in applications, such as in modern quantum devices where TLS are the source of dissipation, decoherence and 1/f noise.

PL

Wszechobecne niskoenergetyczne wzbudzenia są jednym z powszechnych zjawisk w amorficznych ciałach stałych. Wzbudzenia te dominują akustyczne, dielektryczne i termiczne właściwości strukturalnie nieuporządkowanych ciał stałych. Wyjątkiem jest rodzaj uwodornionego amorficznego krzemu (α-Si:H) o zawartości 1 at.% H. Na podstawie niskotemperaturowych badań własności sprężystych i termicznych krzemu amorficznego (α-Si) naparowanego wiązką elektronów wykazaliśmy, że w pewnych warunkach osadzania można wyeliminować TLS w tym układzie tak, że warstwy stają się gęstsze i strukturalnie bardziej uporządkowane. Uzyskane przez nas wyniki wskazują, że TLS nie są nieodłączną cechą stanu szklistego, ale lokują się w regionach o niskim zagęszczeniu sieci amorficznej. Praca niniejsza wyjaśnia, że wodór nie pełni roli w usuwaniu TLS w α-Si:H, jak dotąd sądzono, i wskazuje na idealną czterokrotnie kowalencyjnie związaną amorficzną strukturę jako przyczynę znikania TLS. Nasz wynik potwierdza koncepcję, że z α-Si można wytworzyć “doskonałe szkło” o “podobnych do krystalicznych” właściwościach, oferując w ten sposób zachęcającą możliwość wykorzystania go alternatywnie jako prosty krystaliczny dielektryk w takich aplikacjach jak w nowoczesne urządzenia kwantowe, gdzie TLS są źródłem dyssypacji dekoherencji i szumu 1/f.

10

Wyznaczanie prędkości dźwięku w powietrzu przy użyciu karty muzycznej komputera

Grodzicki M., Adam S.

Aparatura Badawcza i Dydaktyczna

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2014

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T. 19, nr 4

333-340

PL

Praca przedstawia sposób wykonania pomiaru prędkości rozchodzenia się dźwięku w powietrzu przy użyciu karty muzycznej komputera PC. Celem artykułu jest demonstracja prostego układu pomiarowego, umożliwiającego wyznaczenie prędkości dźwięku nawet w warunkach domowych, praktycznie bez nakładów finansowych. Zestaw pomiarowy składa się z komputera wyposażonego w kartę muzyczną, dwóch mikrofonów i głośnika. Generowane dźwięki są odbierane przez mikrofony i analizowane przez napisany na potrzeby projektu program komputerowy. Prezentowane doświadczenie może być wykorzystane w procesie dydaktycznym, np. do demonstracji na wykładach lub jako zestaw do wykonania ćwiczenia na I pracowni fizycznej. Autorzy prezentują stanowisko doświadczalne oraz ilustrują jego działanie wykonanymi pomiarami.

EN

The paper presents a measurement method for the speed of sound in air by using a PC sound card. The aim is to demonstrate a simple measurement system, which allows for measurement of the speed of sound even at home, and is available at minimal cost. The measurement setup consists of a PC with a sound card, two microphones and a speaker. The generated sounds are received by microphones and analyzed by the software specially elaborated for the project. The presented experiment can be used in the teaching process, e.g. as a demonstration at lectures or a setup for physical training lab. The authors present the experimental stand and illustrate its performance with standard measurements.

11

New low-cost method for determination of heating value of natural gas

Rybitskyi I., Karpash O., Darvay I., Karpash M.

Wiertnictwo, Nafta, Gaz

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2011

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T. 28, z. 1-2

333-338

EN

New method for heating value determination has been proposed earlier which lays in simultaneous measurement of carbon dioxide and nitrogen concentrations and speed of sound in natural gas and use of neural network utilized for calculation of heating value. Based on reference data bases application of the method allowed to achieve relative error of 2.6% for heating value determination. Afterwards additional investigation has been made aimed to exclude nitrogen concentration measurement, which also gave good accuracy of heating value determination. Special experimental setup has been developed for experimental verification of the method. Experimental setup included commercial ultrasonic device for speed of sound measurement, special carbon dioxide concentration meter, relative humidity and temperature measuring units. Numerous experiments were completed using the setup with subsequent natural gas chromatographic analysis. Analysis of the achieved results showed good accordance of the theoretical model with experimental data.

PL

W artykule zaproponowano nową metodę określania wartości grzewczej polegającą na równoczesnym pomiarze stężenia dwutlenku węgla i azotu, prędkości akustycznej gazu ziemnego i wykorzystania sieci neuronowych do obliczenia wartości grzewczej. Korzystając z metody opartej na bazie danych odniesienia uzyskano względny błąd 2,6%. Następnie przeprowadzono dodatkowe badanie ukierunkowane na oddzielenie pomiaru stężenia azotu, co również dało dokładny wynik pomiaru wartości cieplnej. Opracowano specjalny zestaw badawczy w celu przeprowadzenia doświadczalnej weryfikacji metody. Zestaw ten składa się z komercyjnego urządzenia ultradźwiękowego do pomiaru prędkości dźwięku, specjalny miernik stężenia dwutlenku węgla, jednostki do pomiaru wilgotności względnej i temperatury. Przeprowadzono równocześnie liczne eksperymenty za pomocą wspomnianego zestawu i analizę chromatograficzną gazu. Analiza uzyskanych wyników wykazała dobrą zgodność teoretycznego modelu z danymi doświadczalnymi.

12

Densities, Viscosities and Speeds of Sound of Binary Mixtures of Stereoisomeric Decalins

Siporska A., Szydłowski L.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 4

599-605

EN

Densities, viscosities and speeds of sound for the binary mixture of cis- and transdecalins have been measured over the whole composition range at 293.15 K and 305.15 K. The limiting partial volumes, excess volumes, deviations in viscosity and isentropic compressibilitywere calculated. It appeared that the mixture of stereoisomeric decalins is characterized by a moderate excess volume and relatively small deviations in viscosity and isentropic compressibility. The results were fitted to the Redlich – Kister equation.

13

Isotope effects on selected physicochemical properties of nitromethane and 1-pentanol

Makowska A., Szydłowski J.

Nukleonika

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2006

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Vol. 51,suppl.2

81-85

EN

Densities, kinematic viscosities, speed of sound and refractive indices of nitromethane and 1-pentanol and their deuterated derivatives CD3NO2 and C5H11OD were measured. The data obtained allowed to calculate molar volumes, dynamic viscosities, isentropic compressibilities and isobaric thermal expansion. Deuterium isotope effect on the selected physicochemical properties of both nitromethane and 1-pentanol has been determined. Large isotope effects characterizing density, viscosity and speed of sound are observed for nitromethane and much smaller for 1-pentanol. Isotope effects on molar volume are small both for nitromethane and 1-pentanol, but of the opposite sign. These observations are in agreement with the expectations.

14

Influence of H/D Isotope Substitutio on Physicochemical Properties of Aqueous Solutions of Urea and Thiourea

Jelińska-Kazimierczuk M., Szydłowski J.

Polish Journal of Chemistry

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2001

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Vol. 75, nr 1

115-125

EN

The influence of the H/D isotope substitution on excess volumes, partial molar volumes, viscosity and ultrasound speed in aqueous solutions of urea and thiourea are studied at 20 C. The excess volume of the solutions studied is relatively small - however, it is negative in urea and positive in thiourea solutions. On the other hand, the deuteration affects the excess volume in both solutions in the same way: deuterated systems show smaller deviation from additivity than regular ones. The speed of sound in the systems studied increases monotonously with concentration, but its isotope effect decreases as the concentration increases. The curves of viscosity are monotonous too, but isotope effect of kinematic viscosity is practically the same in the whole concentration range studied. The present results for urea and thiourea aqueous solutions are compared with those previously obtained for amide-water systems.

15

O prędkości dźwięku w ośrodkach porowatych

Włodarczyk E., Jackowski A., Janiszewski J.

Problemy Techniki Uzbrojenia

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1998

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R. 27, nr 64

81--93

PL

W pracy dokonano syntezy danych literaturowych uzupełnionych własnymi analizami, dotyczących propagacji małych zaburzeń w płynach. Szczególną uwagę zwrócono na prędkość dźwięku w dwuskładnikowych układach dyspersyjnych. Ośrodkiem rozpraszającym jest ciecz a rozproszonym gaz. W prezentowanej pracy wyprowadzono zamknięte wzory na trzy rodzaje lokalnych prędkości propagacji fal akustycznych w dyspersoidzie ciecz idealna-gaz: - izotermiczną (temperatura gazu w pęcherzykach jest taka sama jak w otaczającej jej cieczy); - izentropowa (gaz w pęcherzykach sprężony jest izentropowo według adiabaty Poissona); - uderzeniową ( gaz w pęcherzykach sprężony jest w sposób udarowy - za pomocą fali uderzeniowej). Wzory wyprowadzono przy założeniu, że gaz nie rozpuszcza się w cieczy. Wyniki pracy mogą być wykorzystane w zagadnieniu tłumienia fal uderzeniowych działających na różne obiekty wojskowe (łodzie podwodne, okręty, fortyfikacje), a także przy badaniu rozpadu dowolnych nieciągłości w problemach balistyki wewnętrznej i rurach uderzeniowych oraz przy interpretacji zjawisk towarzyszących generacji strumieni kumulacyjnych z wkładek spiekanych.