MyMedR

Displaying publications 21 - 40 of 104 in total

Abstract:

Sort:

Optimisation of ultrasound-assisted extraction of oil from papaya seed by response surface methodology: oil recovery, radical scavenging antioxidant activity, and oxidation stability

Samaram S, Mirhosseini H, Tan CP, Ghazali HM, Bordbar S, Serjouie A

Food Chem, 2015 Apr 1;172:7-17.
PMID: 25442517 DOI: 10.1016/j.foodchem.2014.08.068

The present study aimed to investigate the effects of ultrasound-assisted extraction (UAE) condition on the yield, antioxidant activity and stability of the oil from papaya seed. The studied ultrasound variables were time, temperature, ultrasound power and solvent to sample ratio. The main goal was to optimise UAE condition providing the highest recovery of papaya seed oil with the most desirable antioxidant activity and stability. The interaction of ultrasound variables had the most and least significant effects on the antioxidant activity and stability, respectively. Ultrasound-assisted extraction provided a relatively high oil recovery (∼ 73%) from papaya seed. The strongest antioxidant activity was achieved by the extraction at the elevated temperature using low solvent to sample ratio. The optimum ultrasound extraction was set at the elevated temperature (62.5 °C) for 38.5 min at high ultrasound power (700 W) using medium solvent to sample ratio (∼ 7:1 v/w). The optimum point was practically validated.

Matched MeSH terms: Ultrasonics/methods*
Extraction of bioactives from Orthosiphon stamineus using microwave and ultrasound-assisted techniques: Process optimization and scale up

Chan CH, See TY, Yusoff R, Ngoh GC, Kow KW

Food Chem, 2017 Apr 15;221:1382-1387.
PMID: 27979103 DOI: 10.1016/j.foodchem.2016.11.016

This work demonstrated the optimization and scale up of microwave-assisted extraction (MAE) and ultrasonic-assisted extraction (UAE) of bioactive compounds from Orthosiphon stamineus using energy-based parameters such as absorbed power density and absorbed energy density (APD-AED) and response surface methodology (RSM). The intensive optimum conditions of MAE obtained at 80% EtOH, 50mL/g, APD of 0.35W/mL, AED of 250J/mL can be used to determine the optimum conditions of the scale-dependent parameters i.e. microwave power and treatment time at various extraction scales (100-300mL solvent loading). The yields of the up scaled conditions were consistent with less than 8% discrepancy and they were about 91-98% of the Soxhlet extraction yield. By adapting APD-AED method in the case of UAE, the intensive optimum conditions of the extraction, i.e. 70% EtOH, 30mL/g, APD of 0.22W/mL, AED of 450J/mL are able to achieve similar scale up results.

Matched MeSH terms: Ultrasonics/methods*
Pomegranate peel-derived punicalagin: Ultrasonic-assisted extraction, purification, and its α-glucosidase inhibitory mechanism

Liu Y, Kong KW, Wu DT, Liu HY, Li HB, Zhang JR, et al.

Food Chem, 2022 Apr 16;374:131635.
PMID: 34823934 DOI: 10.1016/j.foodchem.2021.131635

The pomegranate peel is a by-product of pomegranate fruit rich in polyphenols. In this study, pomegranate peel polyphenols were explored using LC-MS/MS, and punicalagin was the most abundant compound. The highest yield (505.89 ± 1.73 mg/g DW) of punicalagin was obtained by ultrasonic-assisted extraction (UAE) with the ethanol concentration of 53%, sample-to-liquid ratio of 1:25 w/v, ultrasonic power of 757 W, and extraction time of 25 min. Punicalagin was further purified by the macroporous resin D101 and prep-HPLC, reaching the purity of 92.15%. The purified punicalagin had the IC50 of 82 ± 0.02 µg/mL against α-glucosidase, similar to the punicalagin standard with IC50 of 58 ± 0.014 µg/mL, both exhibiting a mixed inhibitory mechanism. Molecular docking further revealed that a steric hindrance with the intermolecular energy of -7.99 kcal/mol was formed between punicalagin and α-glucosidase. Overall, pomegranate peel is a promising source of punicalagin to develop anti-diabetic functional foods.

Matched MeSH terms: Ultrasonics
Fulltext Response surface optimization of ultrasonic-assisted extraction of carotenoids from oil palm (Elaeis guineensis Jacq.) fronds

Ofori-Boateng C, Lee KT

Food Sci Nutr, 2013 05;1(3):209-221.
PMID: 29387349 DOI: 10.1002/fsn3.22

Oil palm (Elaeis guineensis Jacq.) fronds (OPF) are the most abundant oil palm solid wastes that are generated during oil palm agriculture and harvest. Palm oil and some other palm wastes have been reported to contain high concentrations of carotenoids with vital bioactive properties. However, the extraction and quantification of carotenoids from OPF have not been reported. In this study, ultrasonic-assisted extraction, HPLC-FLD for quantification, and response surface methodology (RSM) for optimization of β-carotene, lutein, and zeaxanthin from OPF extracts were investigated. The effects of extraction temperature (X1: 30-70°C), extraction time (X2: 10-50 min), and solvent-sample ratio (X3: 10-50 mL/g) on the recovery of β-carotene (Y1), lutein (Y2), and zeaxanthin (Y3) were investigated using three-level Box-Behnken design (BBD) experiment. At a desirability of 1, the optimum extraction conditions for β-carotene (30.14°C, 37.11 min, and 23.18 mL/g), lutein (30.00°C, 39.09 min, and 19.24 mL/g), and zeaxanthin (30.09°C, 36.76 min, and 22.38 mL/g) yielded carotenoid concentrations of 17.95 μg/g dry weight (DW), 261.99 μg/g DW, and 29.99 μg/g DW, respectively.

Matched MeSH terms: Ultrasonics
Fulltext Development of a Novel Design and Subsequent Fabrication of an Automated Touchless Hand Sanitizer Dispenser to Reduce the Spread of Contagious Diseases

Das A, Barua A, Mohimin MA, Abedin J, Khandaker MU, Al-Mugren KS

Healthcare (Basel), 2021 Apr 10;9(4).
PMID: 33920290 DOI: 10.3390/healthcare9040445

BACKGROUND: The use of a touchless automated hand sanitizer dispenser may play a key role to reduce contagious diseases. The key problem of the conventional ultrasonic and infra-red-based dispensers is their malfunctioning due to the interference of sunlight, vehicle sound, etc. when deployed in busy public places. To overcome such limitations, this study introduced a laser-based sensing device to dispense sanitizer in an automated touchless process.
METHOD: The dispensing system is based on an Arduino circuit breadboard where an ATmega328p microcontroller was pre-installed. To sense the proximity, a light-dependent resistor (LDR) is used where the laser light is to be blocked after the placement of human hands, hence produced a sharp decrease in the LDR sensor value. Once the LDR sensor value exceeds the lower threshold, the pump is actuated by the microcontroller, and the sanitizer dispenses through the nozzle.
RESULTS AND DISCUSSION: A novel design and subsequent fabrication of a low-cost, touchless, automated sanitizer dispenser to be used in public places, was demonstrated. The overall performance of the manufactured device was analyzed based on the cost and power consumption, and environmental factors by deploying it in busy public places as well as in indoor environment in major cities in Bangladesh, and found to be more efficient and cost-effective compared to other dispensers available in the market. A comprehensive discussion on this unique design compared to the conventional ultrasonic and infra-red based dispensers, is presented to show its suitability over the commercial ones. The guidelines of the World Health Organization are followed for the preparation of sanitizer liquid. A clear demonstration of the circuitry connections is presented herein, which facilitates the interested individual to manufacture a cost-effective dispenser device in a relatively short time and use it accordingly. Conclusion: This study reveals that the LDR-based automated hand sanitizer dispenser system is a novel concept, and it is cost-effective compared to the conventional ones. The presented device is expected to play a key role in contactless hand disinfection in public places, and reduce the spread of infectious diseases in society.

Matched MeSH terms: Ultrasonics
Fulltext Toughness, elasticity and physical properties for the evaluation of foamed concrete reinforced with hybrid fibers

Dawood ET, Mohammad YZ, Abbas WA, Mannan MA

Heliyon, 2018 Dec;4(12):e01103.
PMID: 30603721 DOI: 10.1016/j.heliyon.2018.e01103

This study has been undertaken to investigate the evaluation of Fiber-reinforced Foamed Concrete (FRFC) performance by the use of toughness and non-destructive tests. These tests cover the workability, density, static modulus of elasticity, toughness, ultrasonic pulse velocity and absorption tests. Different FRFC mixes using carbon fibers in the order of 0.5, 1 and 1.5% carbon fibers were used. Also, the combinations of carbon fibers (C) and polypropylene fibers (PP) as 1% C+ 0.5% PP, and 0.5% C+1% PP were prepared. Lastly, the inclusion of polypropylene fibers with the order of 1.5% PP was used to strengthen the foamed concrete mix. The results showed that the use of 1.5% of C has affected the modulus of elasticity and flexural toughness of foamed concrete. On the other hand, a strong relationship is found between compressive strength and ultrasonic pulse velocity for FRFC.

Matched MeSH terms: Ultrasonics
Combined cytological and histological diagnosis of hepatocellular carcinoma in ultrasonically guided fine needle biopsy specimens

Zainol H, Sumithran E

Histopathology, 1993 Jun;22(6):581-6.
PMID: 7689070

This study evaluates the usefulness of a combined cytological and histological approach to the diagnosis of hepatocellular carcinoma (HCC) when applied to fine needle biopsy specimens obtained under ultrasonic guidance. The material, aspirated from 51 focal liver lesions, was handled in such a way that there was sufficient material for both cytological and histological (cell block) assessment. Of the 29 cases of HCC studied, a confident cytological diagnosis was made in 23 (79%). In the remaining six cases, the cytological features were considered to be suspicious but not diagnostic of HCC. Examination of cell blocks in the six cases enabled a confident diagnosis of HCC to be made in all cases. This was due to the supplementary visual information provided by the histological features, particularly the pattern of arrangement of the tumour cells.

Matched MeSH terms: Ultrasonics
Fulltext Detection of foreign bodies in canned foods using ultrasonic testing

Meftah, H., Mohd Azimin, E.

International Food Research Journal, 2012;19(2):543-546.
MyJurnal

Foreign bodies in packaged foods may pose both a safety risk and a risk of perceived degradation of
quality. When food products are manufactured or packaged, small foreign objects might end up in the product. It is naturally desirable for the food industry that all foreign bodies are detected and removed before they reach customers. In this study, the ultrasonic method was used to detect the foreign bodies in canned foods. In order to establish a technical concept for the detection of foreign bodies in canned foods, an experimental investigation was carried out using pulse-echo ultrasonic testing. A number of simulated foreign object pieces were deliberately put inside the canned food and the results were analyzed. The approach demonstrates that ultrasound has potential for application in many industrial food packaging environments where foreign objects need to be detected. Indeed, detection up to 4 millimeter foreign body size has been done for rock and metal foreign bodies.

Matched MeSH terms: Ultrasonics
Fulltext Ultrasound-assisted extraction of valuable compounds from winter melon (Benincasa hispida) seeds

Bimakr, M., Rahman, R.A., Saleena Taip, F., Adzahan, N.M., Islam Sarker, Z., Ganjloo, A

International Food Research Journal, 2013;20(1):331-338.
MyJurnal

Ultrasound-assisted extraction (UAE) was applied for the extraction of bioactive valuable compounds from winter melon (Benincasa hispida) seeds. Effects of amplitude (25-75%), temperature (40-60°C) and sonication time (20-60 min) on crude extraction yield (CEY) and radical scavenging activities (RSA, % inhibition of DPPH˙ and ABTS˙+ free radicals) of extracts were determined using complete randomised design (CRD). The results showed that the CEY and RSA of extracts significantly affected by independent variables. The maximum value of CEY (97.14±0.36 mgg-1), scavenging of DPPH˙ radicals (32.12 ± 0.38%) and scavenging of ABTS˙+ radicals (40.52±0.73%) were obtained at the combined treatment conditions of 75%, 55°C and 40 min. The UAE results obtained were compared with those achieved by using conventional Soxhlet extraction (CSE) method. It was found UAE allowed extraction at lower temperature and the extracts obtained posses higher quality compare with CSE. UAE is a promising environment friendly technique for the extraction of bioactive compounds from winter melon (Benincasa hispida) seeds.

Matched MeSH terms: Ultrasonics
Fulltext Effect of heat and thermosonication on kinetics of peroxidase inactivation and vitamin C degradation in seedless guava (Psidium guajava L.)

Ali, G., Russly, A.R., Jamilah, B., Azizah, O., Mandana, B.

International Food Research Journal, 2011;18(4):1289-1294.
MyJurnal

This study aims to evaluate the effect of heat and the simultaneous application of heat (80-95°C) and ultrasonic waves (thermosonication) on the inactivation kinetic of peroxidase and vitamin C degradation in seedless guava. Ultrasonic wave’s amplitudes except 25 and 100% had significant (P 0.98). In the heat blanching process, the peroxidase inactivation rate constant increased from 1.1×10-2 to 4.6×10-2 s-1. However, the inactivation rate of peroxidase was increased by 1.5–3 times in the temperature range 80–95ºC, with the 50 and 75% ultrasonic wave amplitudes, respectively. Decreases in vitamin C contents due to blanching treatments were found. Blanching processes at high temperature and short time resulted in higher vitamin C retention. It was found that thermosonication treatment inactivates seedless guava peroxidase at less severe blanching conditions and consequently retains vitamin C content at higher levels. The present findings will help to design the blanching conditions in order to reduce the severity of conventional thermal treatments and, therefore, improving the quality of the thermally treated product.

Matched MeSH terms: Ultrasonics
Fulltext Effects of process conditions on the ultrasonic extraction of phenolics scavenger from Curcuma Caesia Rhizome

Jemain, S.F.P., Jamal, P., Raus, A. R., Amid, A., Jaswir, I.

International Food Research Journal, 2017;24(101):0-0.
MyJurnal

Medicinal properties of Malaysian Curcuma caesia have not been studied extensively, even though it has been used as a traditional remedy. This study examined the effects of various extraction temperatures (30, 40, 50, 60, 70oC) using a high frequency (40 kHz) ultrasonic extraction method, time (30,60,90 and 120 minutes), pH (1,2,3,4,5,6,7,8,9,10) on the extraction yield of total phenolics and DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging activities from C. caesia rhizome. Extraction was most efficient at pH 6.0, while the extraction time of 30 minutes and temperature of 60oC was the best in terms of total phenolics content and DPPH scavenging activity. This study is important due to its ability to improve extraction of total phenolics compound using ultrasonic extraction method while maintaining a relatively high DPPH scavenging activity of the extracts.

Matched MeSH terms: Ultrasonics
Fulltext Effect of extraction methods on yield, oxidative value, phytosterols and antioxidant content of cocoa butter

Roiaini, M., Norhayati, H., Seyed, H.M., Jinap, S.

International Food Research Journal, 2016;23(5):47-54.
MyJurnal

Cocoa beans are rich in numbers of beneficial bioactive compounds such as phenolics and
phytosterols, which benefits to human being. The suitable extraction method is needed to
produce high quality and quantity of cocoa butter and other bioactive compounds. There are
many extraction method to extract these compounds such as Soxhlet extraction, supercritical
fluid extraction, ultrasound extraction method and others. The objective of this study is to
determine the effectiveness of the different extraction methods producing high yields of cocoa
butter, lower oxidative value, stable phytosterols and antioxidant content. The cocoa beans were
subjected to different extraction methods such as Soxhlet extraction (SE), Ultrasonic extraction
method (USE), Supercritical carbon dioxide (SCO2
) and Supercritical carbon dioxide with cosolvent
(SCO2
-Ethanol). Cocoa butter extracted using SCO2
-Ethanol has significantly (p

Matched MeSH terms: Ultrasonics
Fulltext Monoamniotic Twin Pregnancy; is There a Need for Frequent Fetal-Doppler Surveillance?

Suhaiza, A., Che Anuar, C.Y., Nik Zuky, N.L., Mokhtar, A.

International Medical Journal Malaysia, 2010;9(2):57-58.
MyJurnal

Monoamniotic twin pregnancy is a rare type of twin pregnancy which poses risk of cord entanglement and
sudden death of either one or both fetuses. The role of antenatal surveillance by Ultrasound Doppler for
umbilical cord and ultrasonic evidence of cord entanglement or knotting may predict the pregnancy outcome
but yet unavoidable. The discussion will include antenatal surveillance in this rare type of pregnancy.

Matched MeSH terms: Ultrasonics
Fulltext Extraction techniques for polycyclic aromatic hydrocarbons in soils

Lau EV, Gan S, Ng HK

Int J Anal Chem, 2010;2010:398381.
PMID: 20396670 DOI: 10.1155/2010/398381

This paper aims to provide a review of the analytical extraction techniques for polycyclic aromatic hydrocarbons (PAHs) in soils. The extraction technologies described here include Soxhlet extraction, ultrasonic and mechanical agitation, accelerated solvent extraction, supercritical and subcritical fluid extraction, microwave-assisted extraction, solid phase extraction and microextraction, thermal desorption and flash pyrolysis, as well as fluidised-bed extraction. The influencing factors in the extraction of PAHs from soil such as temperature, type of solvent, soil moisture, and other soil characteristics are also discussed. The paper concludes with a review of the models used to describe the kinetics of PAH desorption from soils during solvent extraction.

Matched MeSH terms: Ultrasonics
Anti-inflammatory and analgesic activity of novel oral aspirin-loaded nanoemulsion and nano multiple emulsion formulations generated using ultrasound cavitation

Tang SY, Sivakumar M, Ng AM, Shridharan P

Int J Pharm, 2012 Jul 1;430(1-2):299-306.
PMID: 22503988 DOI: 10.1016/j.ijpharm.2012.03.055

The present study investigated the anti-inflammatory and analgesic activities of novel aspirin oil-in-water (O/W) nanoemulsion and water-in-oil-in-water (W/O/W) nano multiple emulsion formulations generated using ultrasound cavitation techniques. The anti-inflammatory activities of nanoemulsion and nano multiple emulsion were determined using the λ-carrageenan-induced paw edema model. The analgesic activities of both nanoformulations were determined using acetic acid-induced writhing response and hot plate assay. For comparison, the effect of pretreatment with blank nanoemulsion and reference aspirin suspension were also studied for their anti-inflammatory and antinociceptive activities. The results showed that oral administration of nanoemulsion and nano multiple emulsion containing aspirin (60 mg/kg) significantly reduced paw edema induced by λ-carrageenan injection. Both nanoformulations decreased the number of abdominal constriction in acetic acid-induced writhing model. Pretreatment with nanoformulations led to a significant increase in reaction time in hot plate assay. Nanoemulsion demonstrated an enhanced anti-inflammatory and analgesic effects compared to reference suspension while nano multiple emulsion exhibited a mild inhibitory effects in the three experimental animal model tests. The results obtained for nano multiple emulsion were relatively lower than reference. However, administration of blank nanoemulsion did not alter the nociceptive response significantly though it showed slight anti-inflammatory effect. These experimental studies suggest that nanoemulsion and nano multiple emulsion produced a pronounced anti-inflammatory and analgesic effects in rats and may be candidates as new nanocarriers for pharmacological NSAIDs in the treatment of inflammatory disorders and alleviating pains.

Matched MeSH terms: Ultrasonics*
Accutome PachPen handheld ultrasonic pachymeter: intraobserver repeatability and interobserver reproducibility by personnel of different training grades

Peyman M, Tai LY, Khaw KW, Ng CM, Win MM, Subrayan V

Int Ophthalmol, 2015 Oct;35(5):651-5.
PMID: 25189684 DOI: 10.1007/s10792-014-9989-6

To assess the intra-observer repeatability and inter-observer reproducibility of central corneal thickness (CCT) measurements of PachPen (Accutome, Inc., Pennsylvania, USA), a hand-held, portable ultrasonic pachymeter when used by an ophthalmic nurse compared to an ophthalmologist. Ophthalmology Clinic, University of Malaya Medical Center In this prospective study, CCT was measured in 184 eyes of 92 healthy subjects, first by a corneal surgeon experienced in ultrasound pachymetry (Observer 1) followed by an ophthalmic nurse new to the procedure (Observer 2). Nine measurements were obtained from each eye by each observer, independently. Measurements were compared between the observers. Coefficients of repeatability and reproducibility were calculated. The Bland-Altman plot was used to assess agreement between observers. Mean age of the study population was 54.3 ± 15.2 years old and consisted of 43.5% male. Mean CCT as measured by Observers 1 and 2 were 528.3 ± 32.9 and 530.7 ± 33.3 µm, respectively. Observer 1 showed higher repeatability of measurements compared to that of Observer 2 (coefficient of repeatability 3.46 vs. 5.55%). The measurements by both observers showed high correlation (0.96) and good agreement (mean difference -2.4 µm; 95% limits of agreement -21.4, 16.7 µm). Coefficient of reproducibility of measurements between observers was 5.08%. Accutome PachPen hand-held ultrasound pachymeters gives excellent intra-observer repeatability and inter-observer reproducibility by personnel of different training grades.

Matched MeSH terms: Ultrasonics
Fulltext Smart Walk Stick for Visually Impaired People: Design and Implementation

Saud, Safaa Najah, Manivannan, Dasarataan, Adzliza Binti Salmi, Lilysuriazna Raya

Journal of Management & Science, 2018;16(2):19-28.
MyJurnal

Nowadays, the scientific knowledge is developing frequently in numerous characteristics to be able to offer versatile and also safe and sound tendency for the users. At this time many of prevalent together with employed indicate by the visually impaired people are using the ivory stick, nonetheless it possesses constraints. With the recent technological innovation, it is easy to prolong the assistance acquire for people who have visual disability throughout their movability; this design endorses a cost-effective ultrasonic stick for visually encountered people today, to be able to achieve an exclusive self-reliance and even exempt from the additional assist. A portable convenient to use technology is designed which could recognize the obstructions in the way working with ultrasonic sensors in addition to vibrator. Ultrasonic sensors will be able to inspect three types of distinct heights. Vibrator is frequently used as a substitute gadget in the areas that surrounds with the minimal signal coverage also nosy environment. The buzzer and vibration motor are initialized while any kind of hindrance is identified. Global positioning system device presents the details about to the proceeding approach both work or even home, that has been supplied considering that control keys together with a contingency switch. Text message unit is utilized by the blind to send out SMS info to the saved phone numbers in the Arduino in the event of unexpected emergency.

Matched MeSH terms: Ultrasonics
Fulltext Towards a New Innovation of Smart Bat Hat for Visually Impaired People

Saud, Safaa Najah, Muhammad Irsyad Abdullah, Siti Hadijah Shariff, Ram Singh, Ambrick Singh, Baharudin Hamzah, Nordayati Mat Lehat, et al.

Journal of Management & Science, 2018;16(2):54-66.
MyJurnal

Blindness is an area of inadequate the visual conception because of physiological or even neurological aspects. The partial blindness corresponds to the insufficient integration in the expansion of the optic confidence or perhaps visual center of the eye, and also over-all total blindness is the complete inadequacy of the visual light perception. Within this research, a basic, inexpensive, friendly user, sensible blind assist technique is developed to be integrated with the portability of both blind and even visually impaired people in a particular region. The presented work consists of a wearable apparatus is made up of the head hat to facilitate the blind particular person to get around single-handedly safely and securely in order to keep away from any kind of obstructions that could be experienced, even if mounted and also mobile phone, to avoid virtually any probable accident. The primary function of this product is the Ultrasonic sensing unit which is able to inform the blind people if there exist any specific obstacles or otherwise not around them along with the vibrating motor probably would informs the blind people who which negative are the obstacles located. In addition, by pressing the home or work button this system will straight away link to MIT app inventor and the app will send a signal to Google maps to guide the blind people to its desired location. The implemented system is fast, and easy to use and an innovative affordable solution to blind and visually impaired people in third world countries.

Matched MeSH terms: Ultrasonics
Fulltext Production of talc nanosheets via fine grinding and sonication processes

Palaniandy, Samayamutthirian, Noorina Hidayu Jamil, Khairun Azizi Mohd Azizli, Syed Fuad Saiyid Hashim, Hashim Hussin

Journal of Nuclear and Related Technologies, 2009;2009(1):255-265.
MyJurnal

Fine grinding of high purity talc in jet mill at low grinding pressure was carried out by varying the feed rate and classifier rotational speed. These ground particles were sonicated in laboratory ultrasonic bath by varying the soniction period at five levels. The ground and sonicated particles were characterized in terms of particle size and particle size distribution. Mechanochemical and sonochemical effect of talc was determine via X-ray diffraction. Particle shape and surface texture of the ground and sonicated product was determined via scanning electron microscope and transmission electron microscope. The ground particle size exhibited particle size below 10 µm with narrow size distribution. The reduction of peak intensity in (002) plane indicated the layered structure has been distorted. The sonicated talc shows that the thickness of the talc particles after the sonication process is 20 nm but the lateral particle size still remains in micron range. The reduction of the XRD peak intensity for (002) plane and thickness of sonicated talc as shown in SEM and TEM micrographs proves that fine grinding and sonication process produces talc nanosheets.

Matched MeSH terms: Ultrasonics
Fulltext Small scale imaging using ultrasonic tomography

Zakaria, Z., Fazalul Rahiman, M.H., Abdul Rahim, R., Megat Ali, M.S.A., Baharuddin, M.Y., Jahidin, A.H.

Journal of Nuclear and Related Technologies, 2009;2009(1):266-281.
MyJurnal

Ultrasound technology progressed through the 1960’s from simple A-mode and B-mode scans to today’s M-mode and Doppler two dimensional (2-D) and even three dimensional (3-D) systems. Modern ultrasound imaging has its roots in sonar technology after it was first described by Lord John Rayleigh over 100 years ago on the interaction of acoustic waves with media. Tomography technique was developed as a diagnostic tool in the medical area since the early of 1970’s. This research initially focused on how to retrieve a cross sectional images from living or non-living things. After a decade, the application of tomography systems span into the industrial area. However, the long exposure time of medical radiation-based method cannot tolerate the dynamic changes in industrial process two phase liquid/gas flow system.. An alternative system such as a process tomography system, can give information on the nature of the flow regime characteristic. The overall aim of this paper is to investigate the use of a small scale ultrasonic tomography method based on ultrasonic transmission mode tomography for online monitoring of liquid/gas flow in pipe/vessel system through ultrasonic transceivers application. This non-invasive technique applied sixteen transceivers as the sensing elements to cover the pipe/vessel cross section. The paper also details the transceivers selection criteria, hardware setup, the electronic measurement circuit and also the image reconstruction algorithm applied. The system was found capable of visualizing the internal characteristics and provides the concentration profile for the corresponding liquid and gas phases.

Matched MeSH terms: Ultrasonics

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links