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The potential of ultrasound as a process intensification technique in the extraction of lead from a landfilled metallurgical residues is explored. The silent or non-sonicated process makes use of acidic sodium chloride as the leachate with lead leaching in the range of 45% if a three-stage process is followed. The mixture was sonicated in a batch setup manufactured in-house. The yield obtained in silent conditions at the end of 240 min was already obtained within 30 min with ultrasound, which by itself was an improvement of 8 times. The yield of the process as a whole was improved by 19–26%. The reason for this improvement was investigated with respect to the reaction kinetics. The physical effect of ultrasound on the particle size was also studied by laser diffraction analysis. Finally, the improvement when using ultrasound in a multi-stage process was studied and it was shown that yields being obtained at the end of the 3rd stage in silent conditions is already obtained in the second stage when using ultrasound with 20% more selectivity.

This paper describes the electromagnetic field variance estimation in a random printed circuit board (PCB) model due to the unreliability in permittivity and conductivity of the substrate material using a stochastic finite difference time domain (S-FDTD) method. Traditional FDTD method is updated for mean and variance estimation of the electromagnetic field through the random medium by Taylor series approximation and delta method. The correlation coefficient between the constitutive properties is assumed as to bound the variance field. The 2D S-FDTD method is used for simulating variance of fields in PCB model, and the results are validated using Monte Carlo results.

Ultrasound and microreactors are a proven combination with many complementary effects that could lead to substantial improvement in an unit operation. This combination is especially effective in heterogeneous systems where the effectivity depends on improved mass transfer. This work focuses on immiscible liquid-liquid system for the purpose of reactive extraction. Since different flow patterns can be generated in a microreactor, a majority of the work with this combination focuses on the slug flow which is the most common and effective of the flow patterns. This work focuses on parallel flow which is less common due to the stricter conditions required to generate it, but with a more consistent interfacial area in comparison to the slug flow. The qualitative and quantitative effects of using ultrasound to parallel flow is explored with a high speed camera and a model test reactive extraction process. The effect of ultrasonic and operating parameters were studied. An improvement of 2.2 to 2.3 times in yield was obtained at a frequency of 41.57 kHz, amplitude of 590 mV and net applied elec. power of 20 W for a residence time ranging from 2 to 20 s, respectively.

When immiscible liquids are subjected to an ultrasonic field, they form emulsions. This principle has been used to improve the mass transfer characteristics of a liquid-liquid extraction process in microreactor systems. The formation of emulsion and its characteristics are prominently dependent on the properties of the liquids used and this also holds true for emulsion brought about by ultrasound. This paper focuses on the properties of fluids that are reported to have an influence on the cavitation behaviour, namely viscosity, interfacial tension and vapour pressure. These properties were examined by changing the solvent of the organic phase in the hydrolysis of p-nitrophenyl acetate. The study is performed by comparing pairs of solvents that are different in one property but similar in the other two. The pairs selected are toluene – chlorobenzene for viscosity, toluene – methyl Isobutyl ketone for interfacial tension and methyl isobutyl ketone – 2-Methyl tetrahydrofuran for vapour pressure effects. A qualitative study was performed with a high-speed camera in flow to understand the emulsification initiation mechanisms and behaviours. These findings were further explored by performing the sonicated emulsion in a batch-sonicated reactor. The quantitative analysis of the fluid properties was evaluated and compared based on the relative percentage increase in yield upon sonication with respect to their individual silent conditions. The quantitative results were further supported by the quantification of the emulsion performed with an FBRM probe. The results indicate a two times improvement in yield with solvent of lower viscosity as 2 times more droplets were formed in the emulsion. Both the solvent systems with higher interfacial tension and vapour pressure had an improved yield of 1.4 times owing to larger number of droplets formed.

The chemical industry has witnessed many important developments during past decades largely enabled by process intensification techniques. Some of them are already proven at commercial scale (e.g. reactive distillation) while others (e.g. ultrasound-assisted extraction/crystallization/reaction) are on their way to becoming the next-generation technologies. This article focuses on the advances of ultrasound (US)-assisted technologies that could lead in the near future to significant improvements in commercial activities. The aim is to provide an authoritative discussion on US-assisted technologies that are currently emerging from the research environment into the chemical industry, as well as give an overview of the current state-of-the-art applications of US in chemical processing (e.g. enzymatic reactive distillation, crystallization of API). Sufficient information is included to allow the assessment of US-assisted technologies and the challenges for implementation, as well as their potential for commercial applications. © 2017 The Authors. Journal of Chemical Technology & Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

There has been a dramatic increase in the number of patients undergoing long term oral anticoagulation therapy (OAT) with warfarin in recent years. Successful anticoagulation treatment is dependent on the patient’s knowledge of OAT. The present study was undertaken to assess the knowledge regarding OAT among stroke survivors and to determine the association between knowledge and selected socio-personal and clinical variables. The study revealed that only 5 percent of sample had good knowledge and the knowledge level was more among males and those who had previous exposure to lecture class/information pamphlet regarding OAT. Patients had poor knowledge in the area of dietary interaction of warfarin followed by precautions to be taken while on OAT and signs of side effects of OAT.

This work aims at constructing a design which integrates a direct (solid) contact method with temperature control for chemical process applications. To realise this integration a two-step approach is proposed. Firstly, temperature control is achieved by suspending the tubing in a temperature controlled and sonicated liquid medium (indirect contact). Secondly, direct contact elements are introduced at regular intervals along the tubing. Therefore, this design is termed the hybrid contact reactor, as it incorporates both direct and indirect approaches of ultrasound transfer. Furthermore, two possible configurations, open and closed interval connection to the tubing, were assessed. Both hybrid reactors performed better than the indirect contact reactor (20-27% increase in yield) for residence times of less than 45 s and similar for residence times above. Even though the performance of the two hybrid designs was similar the closed interval resulted in more reproducible and distinct yields. This configuration was then scaled up 10 times in internal volume using a 2 mm ID tube. This design showed a relative performance similar to the interval contact design which gave the highest yields thus far for the same operating conditions. (C) 2017 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved. The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7/2007-2013) under grant agreement no NMP2-SL-2012-309874 (ALTEREGO).

Optical colonoscopy is an invasive procedure used to examine surface lining of the colon, by inserting a flexible tube with a light and camera into the body. Virtual colonoscopy is emerging as a non-invasive alternative to optical colonoscopy. This paper describes 3D reconstruction of colon structure from patient specific CT images, interactive visualization and navigation through the reconstructed colon, automated computation of the navigation path and automated polyp detection with 90.91% sensitivity. This enables a doctor to perform a fast diagnosis through virtual exploration of the colon and resort to invasive colonoscopy procedures only if suspicious polyps are detected.

Continuous crystallization is a fast growing application domain in the pharmaceutical industry. Application of ultrasound has been proven to have positive effects like reduction in induction time and Metastable Zone Width (MSZW) in both batch and flow systems. Further understanding of flow-based sonocrystallization is required to achieve industrial level scale up. This work investigates the sonocrystallization of pharmaceutical compounds in a tubular flow crystallizer. Acetyl Salicylic Acid (ASA-Aspirin) is used as a model compound with ethanol and water as solvent and anti-solvent, respectively. Experiments were conducted in silent and sonicated conditions to study the MSZW. Ultrasound made it possible to achieve crystallization within the crystallizer which was not possible in silent conditions, under the tested conditions. Continuous crystallization was achieved at as low as 48 wt% of anti-solvent and crystallization was already seen at a supersaturation of 1.02. In some experiments, temperature rise with ultrasound caused the crystals to re-dissolve within the channels. Better crystallization - no re-dissolution - was achieved by using low ultrasonic power without any loss in the yield. Particle sizes of product crystals were in the range of 4-46 µm. In conclusion, ultrasound was highly effective in enabling anti-solvent crystallization of a pharmaceutical compound in a tubular flow crystallizer. ispartof: Ultrasonics Sonochemistry vol:59 ispartof: location:Netherlands status: published

Our environment is deteriorating for the last two centuries and almost every part of the planethas been touched by it. Environmental degradation is the disintegration of the earth or deterioration of the environmentthrough consumption of assets. The devastation of environments and the obliteration ofwildlifeand pollution of the natural environment are all challenges forIndia. World Bank experts opined that, between 1995 through 2010, India has made one of the fastestprogresses in the world, in addressing its environmental issues and improving its environmental quality. Still,India has a long way to go to reach environmental quality similar to those enjoyed in developed countries.Pollution persist akeychallenge and opportunity for India. The primary source of environmental degradation is human activities. The industrial revolution of 19th century mechanized theproduction and introduced the use of machinery and heavyequipment - which in turn, used fuels as source of energy, which deteriorate the environment.The modern technological advancement, for which we are so proud of, is really the root cause of the environmental deterioration. The degradation has adverse effects on human beings, plants, animalsand micro-organisms. To cope up with the critical situation, we need to make optimum useof resources, sustainable development, application of green concept and aboveall community participation in all developmental activities.Therefore, the protection of environment is needed for sustainable development.

Colon cancer is one of the leading cancers in both men and women across the globe. The incidence is especially high in developed countries and urban settings. Colonoscopy has been the established procedure for screening and early detection of colon cancer. This procedure involves insertion of a colonoscope with a video camera to examine the inner lining of the colon for suspicious polyps and growths which may develop into cancer. This requires two days of elaborate patient preparation to cleanse the colon of any residual matter which may obstruct the procedure. The colon is also air distended to expand it for clear access. The actual procedure itself takes a few hours and usually requires some kind of sedation to reduce the discomfort, especially to elderly patients. Large polyps and improper preparation also may prevent the procedure from completion, requiring repeat procedures. Growths on the outer surface of the colon also go completely undetected. Virtual colonoscopy is emerging as an alternative to conventional colonoscopy. This is simpler, less intrusive and faster. It is not affected by physical blockades and enables visualization of both inner and outer surfaces of the colon. An intrusive procedure is required only if suspicious polyps are located. This paper presents the methods and systems for developing an affordable virtual colonoscopy workstation which can be expanded to other endoscopic procedures also. It was evaluated on 21 independent colon data sets.

A novel reactor was developed for ultrasound-assisted liquid-liquid extraction. This reactor design entails introducing short contact intervals for the nlicrochannel tubing along the reactor plate channel to have a more focused transmission of the ultrasound. The non-contacted parts of the tubing are still under the influence of the ultrasound as a result of the pseudo-sonicated zone created by the adjacent intervals. The effect of introduction of these elements was first studied by compating the thermal profiles with and without the presence of intervals and it was found that the maximum intensities along the channel become focused at these intervals. The influence of the intervals on a sonicated two-phase flow was also studied and revealed a repetitive splitting (at the intervals) and coalescence (downstream from the interval) of the emulsified aqueous phase. This dynamic change in the size of the emulsified aqueous phase introduces additional interfacial area and improves the mass transfer between the phases. The number of intervals was varied between three, five and seven. The five intervals showed the best performance. On comparing the five-interval design with a direct-contact design it was shown that the interval design gave the best improvement in yield for the process conditions studied. (C) 2016 Elsevier B.V. All rights reserved. The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7/ 2007-2013) under grant agreement no NMP2-SL-2012-309874 (ALTEREGO).

Introduction: Plastic is everywhere in today's lifestyle. It is used for packaging, protecting, serving, and even disposing of all kinds of consumer goods. Improper plastic disposal has become a leading problem in both developed and developing countries. As plastic is non-biodegradable in nature, it remains in environment for several years and disposing plastic wastes at landfill are unsafe and has led to various health problems. So researcher felt it is vital that adults should possess knowledge on hazards of plastic wastes and its disposal. Method: In this study cross sectional descriptive survey was used. Adults were selected through probability simple random sampling. The data was collected using a pretested structured questionnaire. The structured-teaching programme was administered at the end of the pre-test. The post-test was carried out after 7 days, using the same tool as the pre-test. The data was analysed using SPSS version 16 and the results expressed as proportions. Results: A total of 100 adults were included in the study. Analysis of data revealed pre-test knowledge score was 42.52%.Considering the level of knowledge of adults, a structured teaching programme was administered. The post-test knowledge score was 80.48%. Hence comparison in pre-test knowledge score and post-test percentage of hazards of plastic waste and its disposal was approximately 37.96%. A significant association between source of information and post-test knowledge was found. Conclusion: A significant number of adults had inadequate knowledge. So researcher felt that awareness programmes regarding hazards of plastic waste and its disposal should be emphasized.

© 2016 Elsevier B.V. A new method to apply ultrasound to a microchannel for liquid-liquid extraction was explored. The microchannel tubes are subjected to the ultrasound by direct contact with the transducer without the presence of a liquid medium. The design was constructed with the objectives of reproducibility, proper control of the ultrasound parameters and visibility of the behaviour of the two phase flow under the influence of ultrasound throughout the length of the channel. Two mechanisms of emulsion formation were observed. The effectiveness of the system under the influence of various operating and design parameters was quantified by calculating the yields of the two phase hydrolysis reaction of p-nitrophenyl acetate. The behaviour under various frequencies and amplitude was explored. At a frequency of 20.3. kHz, amplitude of 840. mV and flow rate of 0.1. ml/min the highest increase in yield was observed, which was almost 2.5 times that of the silent condition. A comparison was also made against silent batch and flow conditions to determine the actual effectiveness of the system. To obtain an identical yield of 75% the required residence time could be reduced by a factor of 20 in the sonicated flow condition compared to the silent batch condition. publisher: Elsevier articletitle: Ultrasound assisted liquid–liquid extraction in microchannels—A direct contact method journaltitle: Chemical Engineering and Processing: Process Intensification articlelink: http://dx.doi.org/10.1016/j.cep.2016.01.003 content_type: article copyright: Copyright © 2016 Elsevier B.V. All rights reserved. ispartof: Chemical Engineering and Processing vol:102 pages:37-46 status: published

Compressed sensing is a revolutionary paradigm in data acquisition and processing, having impact in several fields. In the complex environment of ocean medium, where early detection of underwater targets is vital, compressed sensing assumes great significance as it brings down the computational resource requirements by reducing the data rates and hardware.In this paper DOA estimation is attempted with a linear array targeting underwater vessels. Array processing is investigated with compressed sensing based techniques and adaptive beam forming. Sparse reconstruction models are developed in this context for signal recovery. Finally the algorithms are validated on a real data set collected from an ocean experiment.

In this paper, the problem of direction of arrival estimation of unknown sources in under water scenario, withminimum data acquisition is investigated. The scheme is based onCompressive Sampling, an emerging technique in signal processing, which asserts that data acquisition and signal reconstructionis possible with much less number of measurements. The sparsenature of the angle spectrum is effectively utilized. The targetdata as received by a linear array of acoustic sensors is simulatedand compressed sensing is employed prior to processing. For reconstruction of compressively sampled signals, greedyalgorithms like orthogonal matching pursuit, matching pursuitand weak matching pursuit are employed. The performance ofthese algorithms are assessed and results are compared withconventional MUSIC algorithm.

Underwater acoustic communication is an important research area having significant industrial and marine applications. Ocean exploration and observation, command and control of Autonomous Underwater Vehicles, coastal surveillance etc. are a few among the many applications. Underwater acoustic channel is considered as one of the most difficult communication media used today. Limited low data rate due to the narrow bandwidth of the channel, extensive and time varying Inter Symbol Interference results from multipath propagation etc are the main obstacles in this area. This paper aims to develop an efficient and reliable underwater communication system that solves the above problems very much. The Compressed Sensing (CS) based underwater communication system uses Orthogonal Frequency Division Multiplexing (OFDM) as an alternative to single carrier broadband modulation to achieve high data rate transmission. Compressed Sensing is an attractive technique for transmission of signals at sub-Nyquist rate leading to faster acquisition and power conservation. The proposed system comprising OFDM and CS will be a viable solution for reducing signal degradation and achieving high data rate transmission over an underwater acoustic channel.