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The success of modern electronics is built on the possibility to accurately predict system behavior by using simulation tools. This paradigm can be extended to components such as piezoelectric transducers attached to the electronics. The ability to simulate both piezoelectric transducer and electronics together renders possible effective optimizations at system level, i.e. minimizing size, cost and power consumption. In this paper a computer simulation of a combined electronics and piezoelectric transducer system is explored. The analogy between acoustic wave propagation and wave propagation in an electric transmission line is given. The simulation approach is applied to a pulser-receiver setup for the determination of speed of sound and attenuation in liquids. Experiments and simulations are made for fixed temperature and in the frequency range 1–10 MHz using ethanol, methanol, carbon tetrachloride, acetone, benzene and distilled water as test samples. Comparison shows a good agreement between simulation and experiments. Furthermore, the use of an ultrasonic simulation package allows for the development of the associated electronics to amplify and process the received ultrasonic signals.

The higher harmonic generation technique has been presented to investigate the creep characteristics of nickel-based superalloy. The primary γ′ precipitates became coarsened preferentially in the direction perpendicular to the applied stress axis during the creep deformation and the Vickers hardness decreased with creep time due to loss of interfacial strain between γ matrix and γ′ precipitate. The increase in ultrasonic nonlinearity with increasing creep time is discussed in relation to the directional coarsening of the γ′ precipitates, which was closely related to the scattering and distortion of the ultrasonic wave.

A number of equations have been proposed by workers in the field of liquid state and, upon exploration, these have been found to meet success of varying degrees. Khasare has proposed a new equation of state involving intermolecular potential with three-model parameters. This equation of state has been applied to the binary liquid mixture of benzene, tetrahydrofuran and carbon tetrachloride in 1-4 dioxane. It is observed that there is a close agreement with experimental values for ultrasonic wave velocity, molar volume and, to some degree, volume expansion coefficient. Model parameters are fairly constant over the liquid phase 10 K above m.p. and 10 K below b.p.

This paper concerns the design method and implementation of main modules, dedicated to miniaturized digital ultrasonic devices, using advanced System-on-Chip technique. It is intended to diagnostic imaging applications such as echography. The proposed implementation allows the integration of all acquisition front end as well as signal and video processing on only one single chip. It will make possible to visualize the ultrasound images in real time. It requires high resolution and real-time image processing. The proposed design, which integrates the B-mode processing modules, includes digital beamforming, quadrature demodulation of RF signals, digital filtering, envelope detection, and video processing of the received signals. This system handles 128 scan lines and 6400 samples per scan line with a 90° angle of view span. The design uses a minimum size look-up memory to store the initial scan information. Rapid prototyping based on ARM/FPGA platform combination is used to validate the operation of the described system. This system offers significant advantages of portability and a rapid time to market.

We have conducted simultaneous ultrasonic velocity and pore volume change measurements on a carbonate rock sample. By including of pressure dependent porosity data, we have improved Cheng’s pore aspect ratio spectrum inversion methodology and made the inverted pore aspect ratio spectrum more realistic. Tang’s unified velocity dispersion and attenuation model is modified and extended to poroelastic media with complex pore structure under undrained condition. Using improved pore aspect ratio spectra inversion methodology and modified Tang’s model, we have explored the potential application of pore aspect ratio spectrum in prediction of seismic wave dispersion and attenuation.

The nondestructive determination of the maturity of durian is an important process for quality control. Since durian has specific properties, such as the thickness of peel, non-uniformity of shape, roughness of prickle skin, largeness of size etc., the nondestructive determination of the maturity is hard to perform. This paper proposes two approaches for determining maturity of durian by using nondestructive vibration and ultrasonic. The appropriate vibration and ultrasonic are directly transferred through durian in the region between prickles located at the middle of durian. The measurement of frequency response from vibration of durian is done by using laser doppler. The signal measured by laser doppler is processed to extract high frequency part by wavelet transform and convert into spectrum form. The template matching is performed by correlation between the high frequency spectrum of signal and templates in order to determine the maturity of durain. To evaluate the proposed method, two prototypes of system using force vibration and ultrasonic are constructed. The experiments are performed for comparing with the results of dry-weight percentage method that is considered to be absolutely right destructive way. And the results of template matching by correlation as proposed signal processing are also compared with conventional signal processing such as vibration velocity way and elastic constants way. The results reveal that the methods using force vibration and ultrasonic with template matching are more accurate by 95% approximately.

An alkaline bath was developed for electroless deposition of Co–W–P thin films on a copper substrate. Effects of pH values, various concentrations of reducing agent, and different powers of ultrasonic on composition, microstructure, and magnetic properties of the films were investigated. It was found out that higher pH could improve cobalt atomic percentage and reduce amounts of phosphorus and tungsten in the film while larger amounts of NaH₂PO₂ would decrease the cobalt content but increase the tungsten and phosphors content. The ultrasonic was introduced during the electroless deposition. Few effects of ultrasonic on the cobalt content were observed. X-ray diffraction showed that almost all of the deposited films were crystalline and contained hexagonal cobalt with a preferred crystallographic orientation (002). However, a typical amorphous Co–W–P film, which has smooth surface, and no crystallite with definite grains could be obtained when the concentration of NaH₂PO₂ in the bath was over 1.2 mol/L. The films with rougher and agglomerate nodular structures would be formed in the bath with a higher pH value. Certain power (60 W, 40 kHz) of ultrasonic could smash the grains and led to the formation of a denser and smoother surface. Cracks appeared at the surface of the film when the ultrasonic power was 150 W. Vibration sample magnetometer results showed that the film with maximum magnetization (600 emu/g) and coercivity (1000 Oe) could be achieved when introducing ultrasonic (60 W, 40 kHz) during the deposition.

Effects of the different ultrasonic powers on copper electrodeposition from non-cyanide alkaline baths by using pyrophosphate as complexing agent were investigated by different electrochemical methods. Cyclic voltammetry and current transient measurements were used to characterize the nucleation and growth mechanism. It is very obvious that the reduction potential moves to more positive one as the ultrasonic power increases. The quartz crystal microbalance (QCM) and chronoamperometric method were used to study the relationship between the mass change and the deposition time. It was found that the current efficiency of electrolyte under 0, 60, 80 and 100 W is 91.95%, 92.14%, 89.25% and 96.11%, respectively measured by QCM measurements. The surface morphology of the electrodeposited Cu films is analyzed by scanning electron microscopy (SEM). The morphology of copper films electrodeposited under the power of 60 W and 80 W presents a compact surface and the grains are fine and uniform.

We successfully obtained Ni–B and Ni–B–Ce coatings with and without sonication on low-carbon steel (Q235) through electroless plating with the deposition time of 60min. The surface morphology and elemental composition of the coatings were evaluated by scanning electron microscopy (SEM) and inductively coupled plasma (ICP). The 11$\mu$m thick sonicated Ni–B–Ce (Son-Ni–B–Ce) coating is uniform with the composition of Ni 87.1%, B 6.2% and Ce 6.6%. X-ray diffraction (XRD) measurements implied a typical broaden peak around 44^∘, considered as amorphous structure which was confirmed by selected area electron diffraction pattern (SAED). Atomic force microscopy (AFM) showed a typical circular pit of Ni–B–Ce coating and Son-Ni–B–Ce coating. X-ray photoelectron spectroscopy (XPS) revealed the chemical status of coating components. The mechanical and corrosion resistance properties were determined by Vickers hardness tester, potentiodynamic polarization (Tafel) and electrochemical impedance spectroscopy (EIS) in 3.5wt. % NaCl solution. As a result, the Son-Ni–B–Ce coating revealed the optimum hardness (956HV), minimum roughness $R_a$ (92.38nm) and excellent corrosion resistance (3.65$\mu$Acm${}^{-2})$ among all coatings.

Frequently used wettable (SiO${}_2)$ and nonwettable highly oriented pyrolytic graphite (HOPG) surfaces have been investigated for the deposition and shape separation of gold nanorods and rod–sphere mixture using the droplet evaporation method. In this paper, we explore and compare the resulting assembly using immovable and ultrasonic systems. On HOPG, stable evaporation produces monolayer arrays of gold nanorods on the terraces whereas aligned arrays of nanorods at the step-edges of HOPG. However, isolated large islands of nanorods on the terraces of HOPG and aligned nanorods at the step-edges become chaotic under the ultrasonic deposition. Also besides gold nanorods, excess cetyltrimethylammonium bromide (CTAB) molecules in suspension are deposited on the terraces in the form of mono- and multilayers revealed by an atomic force microscope (AFM). Both stable as well as ultrasonic vibration techniques were employed on the rod–sphere mixture over the SiO₂ substrate. Stable drying of a droplet showed order arrays of gold nanorods separated from nanospheres everywhere in the coffee-stain ring. The fascinating assembly has been observed for such suspension deposits obtained under ultrasonic vibrations. Aligned arrays of nanorods covered with CTAB surfactants have been sterically as well as osmotically depleted first nearly all CTAB-coated nanospheres and then self-assembled them with the similar geometries within the coffee-stain ring on the SiO₂ surface. The same separation effect has been observed within the initial pinning as well as everywhere over the terraces of the HOPG.

Ultrasonic frequency vibration coupled micro-wire electrical discharge machining (UFV-$\mu$ WEDM) has received enormous consideration due to its zero-tolerance machining. Nickel chromium (Ni–Cr) space alloys are a natural choice within the aerospace industry, which are exposed to high temperatures and high pressure, such as turbine seals and exhaust liners. This study reveals the impact of the UFV-$\mu$ WEDM influencing machining parameters like ultrasonic frequency vibration (UFV), servo voltage ($V_S$), time on ($T_{\mathrm{\text{on}}}$), cutting angle ($A_C$), time off ($T_{\mathrm{\text{off}}}$), and current (I) on the Ni–Cr space alloy in terms of minimum surface undulation (Ra) with maximum material removal rate ($M_{\mathrm{\text{RR}}}$). The cutting trials are carried out by central composite design (CCD). Analysis of variance (ANOVA) is used to find out the proportionate contribution of several factors, and it discloses that $V_S$ was the significant parameter impacting Ra (64.57%) and $M_{\mathrm{\text{RR}}}$ (61.86%). The performance sequence of significant influencing parameters is $V_S>T_{\mathrm{\text{off}}}>A_C>T_{\mathrm{\text{on}}}>I$. According to desirability analysis (DA), optimum parameters for numerous solutions are $T_{\mathrm{\text{on}}}=8$$\mu$s, $V_S=50$V, $T_{\mathrm{\text{off}}}=14$$\mu$s, $I=3$A, and $A_C=30^{\circ }$. The optimum conditions lead to the highest $M_{\mathrm{\text{RR}}}$ (5.72mm³/min) and the lowest Ra (3.42$\mu$m). Scanning electron, 3D topography, and atomic force microscope images are used to analyze the machined surface.

The ultrasonic is applied during the electrodeposition process of CoMo/Al₂O₃ composite coating on 10# steel to enhance its corrosion resistance in simulated sewage water. The influence of ultrasonic power on the thickness, roughness, chemical composition, surface morphology, and corrosion resistance of the composite coating is investigated. In an aqueous solution, a co-deposition of cobalt and molybdenum can be induced to form CoMo alloy coating. The Al₂O₃ nanoparticles are incorporated into CoMo alloy to form CoMo/Al₂O₃ composite coating. When the ultrasonic power increases from 0W to 100 W, the electrodeposition rate of the composite coating increases from 63.25mg/h to 153.73mg/h, and the thickness of the composite coating also increases from 15.6$\mu$m to 28.1$\mu$m. The surface roughness of composite coating electrodeposited without ultrasonic is about 0.436$\mu$m. The CoMo/Al₂O₃ composite coating electrodeposited at 100W ultrasonic power exhibits the smallest surface roughness of 0.193$\mu$m and presents a denser surface morphology composed of 74.4% Co, 10.3% Mo, and 15.3% Al, resulting in better corrosion resistance with the smallest corrosion current density of only 9.7$\mu$A/cm². However, when the ultrasonic power is 150W, the intense hydrogen evolution on the surface of the cathode reduces the density of the coating surface, which leads to the deterioration of corrosion resistance.

This study examines the machinability of hybrid fiber metal laminates (HFML), which are made by nickel–chromium alloy (IN-625) metal-cored carbon (Ca)/aramid (Ar) fiber laminate using ultrasonic vibration-coupled microwire electrical discharge machining (UV-$\mu$WEDM). Since UV-$\mu$WEDM parameters significantly impact the erosion rate ($E_R$) and surface undulation ($S_U$), the main objective was to identify the optimal machining parameters. The input variables include the pulse on ($P_{\text{on}}$), pulse off ($P_{\text{off}}$), current ($I_C$), cutting inclination ($C_I$), and servo voltage ($S_V$) coupled with ultrasonic vibration (UV). The empirical findings show that the servo voltage ($S_V$) significantly impacts $E_R$ (73.93%) and $S_U$ (70.02%). The performance categorization order of significant influencing variable is $S_V>P_{\text{off}}>C_I>P_{\text{on}}>I_C$. The desirability interpretation generated the optimum setting for minimizing $S_U$ and maximizing $E_R$ is $P_{\text{on}}=8\mu$s, $P_{\text{off}}=14\mu$s, $S_V=50$V, $I_C=3$A, and $C_I=30^{\circ }$. Scanning electron microscopic (SEM) images were used to perform the micro-interlayer analysis on the machined surface. Moreover, creating an appropriate HFML is necessary to cut various shapes and sizes to satisfy the demands of diverse applications. 60% of components in the aerospace sector are reportedly rejected in real time due to dimension departure, poor surface finish, and damage found in the final assembly. Investigating the viability of cutting-edge machining techniques like UV-$\mu$WEDM is crucial to minimize damage and improve the quality of HFMLs.

At present, percutaneous liver biopsy is the gold standard in assessing liver fibrosis such as hepatitis and cirrhosis, but there could be sampling error, and specimens might not represent the state of the whole liver accurately because only about 0.002% of the organ is sampled. In this research, we propose the three-dimensional fiber structure extraction echo filter to realize a quantitative ultrasonic diagnosis. The filter is designed based on a statistical theory, and it is possible to reduce the noise contained in a back scattered ultrasonic echo signal, and to visualize the structure of a fiber.

The aim of this study is to prepare composite nanomaterials and to improve some of their mechanical properties as a creep rate using nanoparticles that are prepared in the laboratory by ultrasound available using Impact Polystyrene (HIPS) and Polyethylene (HDPE) as matrix materials. Nanoclays are made of Bentonite-reinforced materials. This research studies the addition of nanoclays with thermos plastic polymers in weight fraction percentage (1%, 2%, 3% and 4%) and makes a comparison among them.

The yttria-stabilized zirconia (YSZ) nanocrystals with uniform size, high purity, and high degree of crystallinity, were prepared by ultrasonic–microwave-assisted method. The structure, optical properties and morphologies of YSZ nanocrystals were characterized by X-ray powder diffraction (XRD), Raman spectroscopy, UV–vis absorption, scanning electron microscope (SEM) and transmission electron microscopy (TEM). The SEM and TEM images of the YSZ nanocrystals indicate that the product is a mono-dispersion structure with an average particle size of about 25 nm.

Hexagonal phase LaF₃:Tb³⁺ nano/microcrystals were successfully synthesized via ultrasonic-assisted ionic liquid (IL) method. The field emission scanning electron microscope (FESEM) images revealed that the morphologies of the as-prepared LaF₃:Tb³⁺ samples were gradually converted from nanoplates to microcylinders with increasing the concentration of Tb³⁺ ions. The photoluminescent (PL) spectrum shows that all the as-prepared La_1-xTb_xF₃ samples show the characteristic emissions of Tb³⁺⁵D₄ → ⁷F_J (J = 6-3, with ⁵D₄ → ⁷F₅ green emission at 542 nm as the strongest one) transitions. The optimal Tb³⁺-doped concentration is 20 mol.% in the LaF₃ host. The photoluminescence intensity of the La_0.80Tb_0.20F₃ microcylinders prepared by ultrasonic irradiation was largely improved as compared with that of the product prepared by stirring.

In this work, the azo dye Congo red (CR) was degraded by a Fe–In₂O₃ catalyst under the irradiation of ultrasonic. The Fe–In₂O₃ catalyst was prepared by a fast and moderate solvothermal method followed by the characterization of X-ray diffraction and scanning electron microscope. The effects of operating parameters, such as catalyst composition, catalyst dosage, initial dye concentration, ultrasonic power and ultrasonic frequency on degradation process were discussed. In the experiment, the optimum CR removal of 97.75% in 60min was achieved under the conditions, i.e., catalyst dosage of 0.06$\mathrm{\text{g}}\cdot L^{-1}$, CR concentration of 10$\mathrm{\text{mg}}\cdot {\mathrm{\text{L}}}^{-1}$, ultrasonic frequency of 45kHz and ultrasonic power of 100W. Besides, the CR degradation behavior by the catalyst with ultrasonic is well in accordance with the first-order kinetic model.

Ultrasonic (US) and UV-C disinfection technologies have been successfully used in wastewater treatment plants (WWTPs) for disinfection purposes. The US technology is typically used as a pre-treatment step to break down larger particles and make them more susceptible to disinfection. The UV-C technology is commonly used as a final disinfection step in many WWTPs. The study aimed to assess the potential of using Zinc Oxide (ZnO) Nanoparticles (NPs) to improve the effectiveness of UV-C and US disinfection methods in treating wastewater effluent, offering a more comprehensive solution to wastewater treatment. In this experimental study, a Laboratory US Bath (40kHz) and a UV-C lamp (16W) were used. In order to investigate the effectiveness of ZnO NPs in the reduction of microbial load, 5mg/L of ZnO NPs was added to the effluent samples. Then, samples were examined for Total Coliform (TC) and Fecal Coliform (FC) reduction by the standard MPN/100mL test. The Chick‘s law was used to calculate the efficiency of microbial load. The relationship between variables was determined by regression analysis using Excel and SPSS-ver 21 software. In this study, the samples were examined in three groups: Samples that were only exposed to sonication or received UV-C radiation with Turbidity of 18 NTU (Group A) and Turbidity of 5 NTU (Group B), and Samples that received 5 mg/L of ZnO NPs (Group C). By increasing the time from 0.5 min to 10 min in the presence of UV-C, the amount of microbial population decreased, and 2 min was considered the optimal time. The maximum removal efficiencies by US for TC were 74.07,77.7, 85.1% (40∘C) and 92.5,100, and 100% (60∘C) in group A (in 30 min sonication), 85.7, 85.7, 100% (40∘C), respectively, and were 100% in other groups (B and C), respectively. The maximum removal efficiencies by US for FC were 76.4%, 88.2%, and 100% (40∘C) and 88.2%, 100%, and 100% (60∘C) in group A (in 30 min sonication), respectively, and were 100% in other groups (B and C). In this study, an important increase in the disinfection ability of ZnO NPs has been observed in the presence of US and UV-C. So, the ZnO NPs/UV-C and ZnO NPs/US processes are valuable alternatives to conventional disinfection processes by over 90% improvement of disinfection efficiency.

In hot and humid climates, evaporative cooler is coupled with desiccant dehumidifier to obtain effective cooling. To realize the M-cycle-based cooler which combines liquid desiccant regeneration and evaporative cooling in a single apparatus, the effect of different feed water temperature on cooling performance is investigated in this paper. It was observed that wetting water film layer of conventional regenerative evaporative cooler (REC) carries a significant amount of sensible heat from the hot water/solution which reduced the wet-bulb effectiveness of the cooler. To enhance its effectiveness, an ultrasonic atomization mist REC was proposed. The influence of different intake conditions on cooling performance was studied and found that mist REC performed better than conventional cooler for higher feed water temperature. The wet-bulb effectiveness of the cooler ranged from 0.56 to 1.15 with maximum cooling capacity of 580W, which is comparable to the previous studies. This prototype can be further developed to an ultrasonic liquid desiccant waterless evaporative cooler.