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Electroless plating is an important process in printed circuit board and electronics manufacturing but typically requires temperatures of 70‐95°C to give a suitable deposition rate. This is becoming problematic in industry due to the rising price of energy and is a major contribution to production costs. Previous studies have noted beneficial effects of ultrasonic irradiation upon electroless plating processes and it has been reported that sonication can increase the plating rate and produce changes to the chemical and physical properties of the deposited coating. The purpose of this paper is to reduce the operating temperature of an electroless nickel bath by introducing ultrasound to the process.

The deposition rate of an electroless nickel solution was determined by two techniques. In the first method, test coupons were plated in an electroless nickel solution at temperatures ranging from 50‐90°C and the plating rate was calculated by weight gain. In the second approach the mixed potential (and hence the current density at the mixed potential) was determined by electrochemical analysis of the anodic and cathodic reactions. In both cases the plating rate was found with and without the application of an ultrasonic field (20 kHz). The electroless nickel deposits obtained in the plating tests were also analysed to determine the phosphorus content, microhardness and brightness.

The plating rates under ultrasonic agitation were always higher than under “silent” conditions. Most importantly, considering the objectives of this study, the deposition rate under sonication at 70°C was significantly higher than that found with mechanical agitation at 90°C. In addition, the results indicated that the deposits produced in an ultrasonic field had consistently lower phosphorus content, higher microhardness and were brighter than those prepared in an electroless nickel bath that was not sonicated.

Although previous work has been performed on the effect of ultrasound on electroless plating, all these studies have been carried out at the normal operating temperature of the electroless process. In this paper, ultrasound has been applied at temperatures well below those normally used in electroless nickel deposition to determine whether sonication can enable low temperature electroless plating.

The objective of this study was to determine if exposure to a short-term ultrasound basic biology and anatomy course can promote interest in health careers and other science-related endeavors among DHH students.

This was a single-site, prospective observational study of DHH high school students at a Southern California high school. All participants took a pre-test survey prior to the course. Participants then took part in three teaching sessions which taught basic anatomy using point-of-care ultrasound (POCUS). Following instruction, a post-test survey was performed to determine if students had an increased interest in medicine, science and biology (p = 0.151).

28 students were enrolled in the study, with an equal distribution of boys and girls. Initially, subjects reported their interest in medicine at an average of 2.8 ± 1.10. The reported interest in science was 3.0 ± 1.13 and for biology was 3.0 ± 1.19. The change in participants' interest was not statistically significant for medicine (p = 0.791), science (p = 0.225) and biology.

While our data did not demonstrate a statistically significant difference in students' interest in STEM fields after the training course, there were several students who were interested in more hands-on shadow experience after the course. Regardless, this study demonstrates persistent barriers that exist for a person who is deaf or hard of hearing to engage in the STEM fields. Future studies are needed to determine the level of instructional activities that may impact the careers of these students.

Point of care ultrasound has been shown to be an effective teaching modality in medical education. However, to date, no studies have been done to assess the utility of ultrasound in teaching the Deaf and Hard of Hearing (DHH) population.

The effects of ultrasonication on the epoxy resin and its emulsion were investigated to find out the changes in the M_η and molecular structure of epoxy, as well as its room temperature storage stability, centrifugal stability, particle size and its distribution and particle morphology more importantly with the influence of different ultrasonic irradiation time, power and temperature.

The emulsion was prepared using an emulsifier with epoxy resin and by using phase inversion after subjecting to ultrasound irradiation with a power of 200 W at 50°C for 60 min. The changes in the epoxy resin and its emulsion induced by ultrasound were characterized by Ubbelohde viscometer, FT-IR, ¹³C-NMR, high-speed desktop centrifuge, laser particle size analyzer and transmission electron microscope.

The molecular weight of the epoxy resin was initially decreased and then stabilized by the increasing of ultrasonic irradiation time. The mole rate of the epoxy groups in epoxy molecular were decreased by about 14 per cent, resulting from ultrasonic irradiation. The particle size of the emulsion was decreased, while the particle size distribution became uniform in a certain time. The narrow distribution, stable and uniform of waterborne epoxy resin emulsion with more than 60 days room temperature storage period, 80 per cent of the supernatant volume, about 220 nm average particle size was gained with a power of 200 W at 50°C for 60 min.

To overcome the problems commonly encountered with an epoxy emulsion, for example, short storage period and wider particle size, which limit its practical application, the effects of ultrasonic irradiation on the epoxy resin and its emulsion, were investigated. As the stability of emulsion was improved with the introduction of ultrasonic irradiation, the application of epoxy emulsion was improved.

The room temperature storage stability and centrifugal stability of the emulsion were decreased by the mechanical method, and thus, the benefit of an in-depth understanding of the influence of ultrasonic treatment on epoxy resin and its emulsion could further promote the development of water-based coatings.

The purpose of this paper is to present a computational framework for the simulation of patient‐specific atherosclerotic arterial walls. Such simulations provide information regarding the mechanical stress distribution inside the arterial wall and may therefore enable improved medical indications for or against medical treatment. In detail, the paper aims to provide a framework which takes into account patient‐specific geometric models obtained by in vivo measurements, as well as a fast solution strategy, giving realistic numerical results obtained in reasonable time.

A method is proposed for the construction of three‐dimensional geometrical models of atherosclerotic arteries based on intravascular ultrasound virtual histology data combined with angiographic X‐ray images, which are obtained on a routine basis in the diagnostics and medical treatment of cardiovascular diseases. These models serve as a basis for finite element simulations where a large number of unknowns need to be calculated in reasonable time. Therefore, the finite element tearing and interconnecting‐dual primal (FETI‐DP) domain decomposition method is applied, to achieve an efficient parallel solution strategy.

It is shown that three‐dimensional models of patient‐specific atherosclerotic arteries can be constructed from intravascular ultrasound virtual histology data. Furthermore, the application of the FETI‐DP domain decomposition method leads to a fast numerical framework. In a numerical example, the importance of three‐dimensional models and thereby fast solution algorithms is illustrated by showing that two‐dimensional approximations differ significantly from the 3D solution.

The decision for or against intravascular medical treatment of atherosclerotic arteries strongly depends on the mechanical situation of the arterial wall. The framework presented in this paper provides computer simulations of stress distributions, which therefore enable improved indications for medical methods of treatment.

This study aims to investigate the interfacial microstructures of ultrasonic-assisted solder joints at different soldering times.

Solder joints with different microstructures are obtained by ultrasonic-assisted soldering. To analyze the effect of ultrasounds on Cu₆Sn₅ growth during the solid–liquid reaction stage, the interconnection heights of solder joints are increased from 30 to 50 μm.

Scallop-like Cu₆Sn₅ nucleate and grow along the Cu₆Sn₅/Cu₃Sn interface under the traditional soldering process. By comparison, some Cu₆Sn₅ are formed at Cu₆Sn₅/Cu₃Sn interface and some Cu₆Sn₅ are randomly distributed in Sn when ultrasonic-assisted soldering process is used. The reason for the formation of non-interfacial Cu₆Sn₅ has to do with the shock waves and micro-jets produced by ultrasonic treatment, which leads to separation of some Cu₆Sn₅ from the interfacial Cu₆Sn₅ to form non-interfacial Cu₆Sn₅. The local high pressure generated by the ultrasounds promotes the heterogeneous nucleation and growth of Cu₆Sn₅. Also, some branch-like Cu₃Sn formed at Cu₆Sn₅/Cu₃Sn interface render the interfacial Cu₃Sn in ultrasonic-assisted solder joints present a different morphology from the wave-like or planar-like Cu₃Sn in conventional soldering joints. Meanwhile, some non-interfacial Cu₃Sn are present in non-interfacial Cu₆Sn₅ due to reaction of Cu atoms in liquid Sn with non-interfacial Cu₆Sn₅ to form non-interfacial Cu₃Sn. Overall, full Cu₃Sn solder joints are obtained at ultrasonic times of 60 s.

The obtained microstructure evolutions of ultrasonic-assisted solder joints in this paper are different from those reported in previous studies. Based on these differences, the effects of ultrasounds on the formation of non-interfacial IMCs and growth of interfacial IMCs are systematically analyzed by comparing with the traditional soldering process.

This study aims to investigate the effect of ultrasound on interfacial microstructures and growth kinetics of intermetallic compounds (IMCs) at different temperatures.

To investigate the effect of ultrasound on IMCs growth quantitatively, the cross-sectional area of IMCs layers over a confirmed length was obtained for calculating the thickness of the IMCs layer.

The generation of dimensional difference in normal direction between Cu₆Sn₅ and its adjacent Cu₆Sn₅, formation of bossed Cu₆Sn₅ and non-interfacial Cu₆Sn₅ in ultrasonic solder joints made the interfacial Cu₆Sn₅ layer present a non-scallop-like morphology different from that of traditional solder joints. At 260°C and 290°C, the Cu₃Sn layer presented a wave-like shape. In contrast, at 320°C, the Cu₃Sn in ultrasonic solder joints consisted of non-interfacial Cu₃Sn and interfacial Cu₃Sn with a branch-like shape. The Cu₆Sn₅/Cu₃Sn boundary and Cu₃Sn/Cu interface presented a sawtooth-like shape under the effect of ultrasound. The predominant mechanism of ultrasonic-assisted growth of Cu₆Sn₅ growth at 260°C, 290°C and 320°C involved the grain boundary diffusion accompanied by grain coarsening. The Cu₃Sn growth was controlled by volume diffusion during the ultrasonic soldering process at 260°C and 290°C. The diffusion mechanism of Cu₃Sn growth transformed to grain boundary diffusion accompanied by grain coarsening when the ultrasonic soldering temperature was increased to 320°C.

The microstructural evolution and growth kinetics of IMCs in ultrasonically prepared ultrasonic solder joints at different temperatures have rarely been reported in previous studies. In this study, the effect of ultrasound on microstructural evolution and growth kinetics of IMCs was systematically investigated.

To explore the use of power ultrasound as an environmentally friendly heating technology for the pre‐treatment of linen fibres with sodium perborate as the halogen free oxidising agent and to study the impact of this process on its dyeability with reactive dyes.

Exploiting power ultrasound in the wet processes of linen fibres was made in two steps, i.e. ultrasonic pre‐treatment with sodium perborate followed by ultrasonic dyeing with reactive dyes. Therefore, comparative studies between conventional and ultrasonic techniques as well as the different factors that may affect these processes were investigated. The effect of the pre‐treatment on fibre fine structure using X‐ray diffraction technique was also investigated.

The results of the increase of whiteness index indicate that ultrasonic pre‐treatment was better at all studied treatment times and at low temperature. X‐ray diffraction studies on blank, ultrasonically and conventionally pre‐treated linen fibres have shown 70.41, 67.51 and 64.90 per cent crystallinity, respectively. The dyeing of the pre‐treated fibres with Reactive Red 24 was simultaneously carried out under both ultrasonic and conventional heating conditions to study the effect of dye concentrations at different dyeing temperatures. The colour strength values obtained for the dyed samples using ultrasonic at 50°C were slightly higher than those obtained using conventional heating at 80°C. Ultrasonic enhancement in the pre‐treatment and dyeing in terms of the percent increase of colour strength of the dyed fabric was estimated to be 157.94 per cent higher than that of conventional heating method. The results of wet fastness properties of the dyed fibres using ultrasonic revealed improvement relative to those obtained using conventional heating method.

The improved wet processes of linen fibres suggest further investigation to exploit power ultrasound in the wet processes of cellulosic fibres at low temperature using different classes of halogen free bleaching agents and dyeing with different classes of heat‐requiring reactive dyes. Also, this work may inspire the synthesis of new generation of heat‐requiring reactive dyes.

The work presented has significant potential industrial application for cleaner production in textile industries.

The present study of linen pre‐treatment with non‐toxic total chlorine free oxidising agent and its dyeability with reactive dyes using power ultrasound is novel and could be used in the wet processes of linen fibres.

This paper aims to describe and evaluate the traditional methods for effective ink removal during the recycling of printed papers. Additionally, novel techniques for dealing with the newer “difficult to deink” inks such as toners from photocopiers, UV‐cured ink films and liquid toner suspensions or Electroinks^® are to be evaluated.

High intensity ultrasound was applied to pulps derived from papers printed with these newer inks in order to evaluate its effectiveness in detaching the inks from paper and establishing the resultant ink particle size distributions.

When exposed to ultrasound at a frequency of 20 kHz, it was found that “difficult to deink” pulps did exhibit significant ink detachment. In the case of toners, temperature did have an effect on particle breakdown with larger numbers of particles produced at temperatures well below the softening point which was attributed to a greater brittleness of the toner at lower temperatures. Electroinks^® can be effectively de‐inked by exposure to ultrasound coupled with washing under neutral conditions. With all the inks investigated, exposure to ultrasound resulted in the detached ink having particle size distributions that can be removed by conventional flotation and washing techniques.

The exposure of the pulp to ultrasound was only carried out using a batch‐wise process. A future development would be to use a continuous flow system incorporating an annular ultrasound horn.

Introducing ultrasound exposure into a conventional deinking plant, all post‐consumer printed waste paper could be deinked without the use of deinking chemicals.

The findings are of interest to those in paper recycling.

Speckle noise removal in ultrasound images is one of the important tasks in biomedical-imaging applications. Many filtering -based despeckling methods are discussed in many existing works. Two-dimensional (2-D) transforms are also used enormously for the reduction of speckle noise in ultrasound medical images. In recent years, many soft computing-based intelligent techniques have been applied to noise removal and segmentation techniques. However, there is a requirement to improve the accuracy of despeckling using hybrid approaches.

The work focuses on double-bank anatomy with framelet transform combined with Gaussian filter (GF) and also consists of a fuzzy kind of clustering approach for despeckling ultrasound medical images. The presented transform efficiently rejects the speckle noise based on the gray scale relative thresholding where the directional filter group (DFB) preserves the edge information.

The proposed approach is evaluated by different performance indicators such as the mean square error (MSE), peak signal to noise ratio (PSNR) speckle suppression index (SSI), mean structural similarity and the edge preservation index (EPI) accordingly. It is found that the proposed methodology is superior in terms of all the above performance indicators.

Fuzzy kind clustering methods have been proved to be better than the conventional threshold methods for noise dismissal. The algorithm gives a reconcilable development as compared to other modern speckle reduction procedures, as it preserves the geometric features even after the noise dismissal.

High‐frequency transducer arrays that can operate at frequencies above 30 MHz are needed for high‐resolution medical ultrasound imaging. The fabrication of such devices is challenging not only because of the fine‐scale piezocomposite fabrication typically required but also because of the small size of arrays and their interconnects. The purpose of this paper is to present an overview of research to develop solutions for several of the major problems in high‐frequency ultrasound array fabrication.

Net‐shape 1‐3 piezocomposites operating above 40 MHz are developed. High‐quality surface finishing makes photolithographic patterning of the array electrodes on these fine scale piezocomposites possible, thus establishing a fabrication methodology for high‐frequency kerfless ultrasound arrays.

Structured processes are developed and prototype components are made with them, demonstrating the viability of the selected fabrication approach. A 20‐element array operating at 30 MHz is patterned and characterised. Furthermore, an electrode pattern suitable for a 20‐element array operating at 100 MHz is created to demonstrate the state of the art of photolithography processing directly on piezocomposite.

The work reported suggests that ultrasound arrays for real‐time biomedical imaging will be viable at higher frequencies than presently available commercially or previously reported in the research literature.

The main elements of a novel, fully mask‐based process for high‐frequency ultrasound transducer array fabrication are presented in outline in this paper.