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Preprocess Sonication Maintains Quality and Inhibits Browning of Fresh-cut Fruit Using Apples as the Fruit Model
(2024-10-02)
Thuamsuk, Pathitta
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Sinthusamran, Sirima
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Techavuthiporn, Chairat
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Supapvanich, Suriyan
Ultrasonic (US) waves (sound waves) have been used to preserve and improve the quality of fresh fruits and vegetables. The goal of this study was to determine whether pre-process US treatment was useful in reducing browning and retaining certain aspects of fresh-cut ‘Gala’ apples’ quality. The apples were sonicated at a frequency of 120 kHz for 0, 5, 10 and 15 min before processing and then the processed apples were stored at 4±1°C. The US treatment at 5 min significantly delayed the loss of lightness, and increases in colour difference and browning index, and maintained whiteness compared to other treatments. The US treatment at 5 min controlled enzymatic browning reaction, probably due to inhibition of polyphenol oxidase activity. US treatments could delay the loss of hardness compared to the control treatment but had no influence on the total soluble solids content. Interestingly, US treatments induced antioxidant activity in fresh-cut apples during storage. In summary, the 5 min sonication could prevent browning and enhance the quality of fresh-cut apples during storage.
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Magnetic and ultrasonic integrated photocatalytic hydrogen evolution effects with Nanosize CoOCu2OZnO and TiO2 decorated on reduced graphene oxide
(2023-12-01)
Areerob, Yonrapach
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Meng, Zeda
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Ullah, Kefayat
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Wijaya, Karna
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Otgonbayar, Zambaga
In this study, metal oxide composite (CoOCu<inf>2</inf>OZnO) and TiO<inf>2</inf> on graphene oxide composite (CCZ−G−T) were synthesized to improve visible light-driven H<inf>2</inf> evolution through the addition of a cation scavenger, ultrasonic effect, and magnetic field effect. The synthesized nanocomposites were characterized through structural, surface, and electrochemical analyses with band structure. The photocatalyst showed hydrogen production of 792 μmol·g−1 for 4 hours. Moreover, this CCZ−G−T photocatalyst exhibits relatively high photocatalytic activity at (530−810) μmol·g−1 when using a scavenger, 1,190 μmol·g−1 when using a magnetic field of 0.14 T, and 1,230 μmol·g−1 when using ultrasonic waves. The CCZ−G−T composite exhibited 630 μmol·g−1 under a magnetic field condition of 0.14 T for 1 hour, which was significantly higher than the hydrogen production rate of 510 μmol·g−1 under ultrasonic conditions. The current study provides new insights into the magnetic field effect on the hydrogen evolution reaction (HER) of graphene-based photocatalysts.
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Velocity detection by ultrasonic doppler based on multi-time technique analysis
(2019-07-01)
Sudtana, Sukkan
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Prompak, Kriangsak
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Suphramit, Suphawadee
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Sisuk, Noppadon
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Boonjun, Surapol
Experimental result of velocity measuring technique, namely, The ultrasonic Doppler, the technique employs a phase shift oscillator to be combination of signals for mixer replacement and tracks the Doppler frequency, is reported. The received ultrasonic signal was fed to the phase shift oscillator that generate 40.7 kHz of natural frequency as same as transmitted frequency. An output response of received ultrasonic present evidently in Doppler frequency which is proportional to velocity of object. Additionally, The great advantage of the multi-time technique could be used in order to predict its behavior. Measurement results verify the efficacy and agree well with analysis.
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Assessment on a Talking Device of Weight and Height for the Visually Impaired Students
(2018-12-01)
Hatthasin, Upady
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Khongdeach, Thanakorn
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Kuntahong, Patchararudee
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Artharnsri, Arnuparb
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Premashthira, Nol
This study is aimed to facilitate the measurement of weight and height with the body mass index detail for the visually impaired students. We created a digital measuring device that supports digital voice. We focused on reducing the cost and the material required in prototyping while maintaining the quality and accuracy of the device. To achieve this, we used a microprocessor and Ultrasonic sensors to measure the height and the Load Cells to measure weight. We used a digital screen to display the measured results. The users can press buttons, labelled in Braille, to listen to their height, weight, and BMI in Thai language. There are buttons, labelled in Braille, for listening to the measured result. The proposed device has been evaluated by 30 sighted and 15 visually impaired volunteers who extensively used the device and provided scores in five aspects: the speed of device is noticeable, Speech and result-values are consistent, accuracy of weighing, accuracy of measurement of elevation, and the device can work as intended. Assessment of the device received overall satisfactory scores, and due to its relatively low cost, is well-suited for individuals with low income.
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Capacitive measuring of crude palm oil-water mixture
(2017-12-13)
Sriphant, Pongsakun
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Srongprapa, Anupong
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Klongratog, Bhanupol
Oil palm is one of the famous commercial crops of Thailand. The production is in the 3th rank of the south east Asia, and plantation is still increasing every year. To investigate the feasibility of using electrical capacitance measuring technique as an alternative method for low-cost non-destructive, oil palm fresh oil (CPO) and water have been prepared and studied. One group is concerned with the immiscible fluid and another is all ultrasonic shakes. The mass concentration (x) of CPO varied from 0 g/cm3 to 0.9 g/cm3 and then all experiments were tested on room temperature (25oC). Guard parallel structure has been used in conjunction with AD7747 capacitive to digital converter to obtain capacitance value (y). The results show that y = 0.11987x2 - 0.46104x + 0.47418 with r2 = 0.98098. The model for second sample is y = 0.08965x2 - 0.41335x + 0.3731 with r2 = 0.9554. The capacitance of first sample is higher than the second sample. As previously mentioned, this project aims to make benefit of interest on seasonable optimistic harvests.
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Low-temperature preparation of BaCeO3 through ultrasonic-assisted precipitation for application in solid oxide electrolysis cell
(2015-06-20)
Kim-Lohsoontorn, P.
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Paichitra, C.
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Vorathamthongdee, S.
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Seeharaj, P.
Barium cerate (BaCeO<inf>3</inf>) was synthesized using conventional precipitation and ultrasonic-assisted precipitation. The effect of precipitation parameters (precipitation precursor, precipitation agent, agent concentration and temperature) significantly affected %perovskite formation and crystallite size of the product. Precipitation with 1 M (NH<inf>4</inf>)<inf>2</inf>C<inf>2</inf>O<inf>4</inf> induced the formation of a single-phase BaCeO<inf>3</inf> while precipitation with 5-20 M NaOH provided a mixed phase of BaCeO<inf>3</inf> and CeO<inf>2</inf>. The %perovskite increased as increasing precipitation temperature; however, the crystallite size of the product also increased. Increasing ultrasonic intensity (30 and 150 W cm-2) during precipitation was found to increase the %perovskite and to reduce crystallite size. The precipitation with 1 M (NH<inf>4</inf>)<inf>2</inf>C<inf>2</inf>O<inf>4</inf> agent, using ultrasonic intensity at 150 W cm-2, provided single phase BaCeO<inf>3</inf> with crystallite size of 18.4 nm after calcination at 900 °C for 4 h. The electrochemical performance of the BaCeO<inf>3</inf> cell under steam electrolysis condition (controlled voltage from OCV to 1.5 V; 20% H<inf>2</inf>O, 40% H<inf>2</inf>, and 40% N<inf>2</inf>) was measured (600-800 °C) and the activation energy of conduction was calculated to be 0.78 eV.
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Ultrasonic measuring circuit using sample and hold method
(2008-12-01)
Rerkratn, Apinai
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Akejakrawan, Sakolkrit
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Kaewpoonsuk, Anucha
This paper presents the simple ultrasonic measuring circuit using sample and hold method. The proposed method is to measure the transit time of ultrasonic wave in fluid. The system consists of the pulse generator circuit, amplifier circuits, band pass filter, detector circuit, comparator circuit, timing circuit, saw-tooth generator circuit, and sample and hold circuit. The voltage output signal of the proposed technique is proportional to the transit time. The sugar solution with differential concentrations was measured in our experiment as an illustrative case study. Experimental results show that the proposed method can measure the transition time of the ultrasonic signal with satisfied sensitivity and good linearity. © 2008 SICE.

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