Sritham, Eakasit
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Sritham, Eakasit
Alternative Name
Sritham, E.
Sritham, Earasit
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Email
eakasit.sr@kmitl.ac.th
12 results
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Item type:Publication, Similarity model for estimating the error of clamp-on ultrasonic flowmeter: Flow in water supply piping system(2017-01-01); ; This study was aimed at presenting the similarity model for the estimation of error of a clamp-on, transit-time ultrasonic flow measurement. Dimensional analysis was based on the Buckingham Pi’s theorem. The groups of independent parameters that were taken into account for the analysis included pipe characteristic, fluid characteristic, and meter installation setting. Experimental testing section was fabricated using PVC pipes with diameters of 1-in and 2-in and 45º PVC elbows. Flow velocity was fixed at 0.5 m/s. The upstream and downstream distances were in the ranges of 2D-20D and 2D-10D, respectively. It was found that the upstream and downstream distances greatly affected the accuracy of the measurement. Larger relative errors were found from the measurement on the smaller pipe. With the installation of ultrasonic transducers according to the recommended value by FCI, the error obtained with the measurements on 1-in and 2-in diameter pipes were, respectively, 7% and 0.35%. The acceptable measurement ranges of upstream distance for 1-in and 2-in diameter pipes were 16D-20D and 6D-20D, respectively. The measurements on a 2-in diameter pipe with a downstream distance in a range of 4D-10D was acceptable. For the 1-in diameter pipe, any downstream distance less than 10D resulted in unacceptable error. The accuracy of measurement was more sensitive to the change of downstream distance than the change of upstream distance. The applicable range of the prototype prediction equation was greatly affected by the flow model. The equation obtained with a 1-in diameter flow model could only be used to predict a 2-in diameter prototype within a range of 18D-20D. Increasing the size a flow model could greatly broaden the applicable range the applicable range of the prediction equation. A 2-in diameter flow model could be used to predict a prototype upto 150 in. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Enthalpy relaxation in sucrose-maltodextrin-sodium citrate bioglass(2017-10-01); Gunasekaran, SundaramGlass transition characteristics of sucrose (SC)-maltodextrin (MD)-sodium citrate (NaCit) bioglass system were investigated using differential scanning calorimetry. Samples were formulated with different SC:MD (7:3, 5:5 and 3:7 by mass) and NaCit/SC (0, 0.1 and 0.2 by mole) ratios, and were equilibrated to residual moisture contents of 0.27–0.35 %wb. Isothermal aging experiments were conducted with the degree of undercooling from 12 to 57 °C and aging times of 8, 20, 47 and 71 h. In general, the Kohlrausch-Williams-Watts (KWW) decay function fit well with the experimental enthalpy relaxation data. The enthalpy relaxation time (τ<sup>KWW</sup>) and the time required for 50% completion of theoretical possible maximum enthalpy relaxation at constant temperature (t<inf>ϕ(t)=0.5</inf>) increased with increasing MD content; lowering the aging temperature had similar effects on τ<sup>KWW</sup> and t<inf>ϕ(t)=0.5</inf>. In the system with high SC and NaCit concentrations (SC:MD = 7:3 and NaCit/SC = 0.2), a substantial increase in τ<sup>KWW</sup> and t<inf>ϕ(t)=0.5</inf> were observed when aging temperature <inf>decreased slightly;</inf> these systems also exhibited the greatest apparent activation energy. The findings reveal that NaCit can enhance the stability of low-moisture bioglass by primarily interacting with SC and form large less-mobile clusters, which helps to improve glass transition temperature and restrict the matrix mobility. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Estimation of thermal conductivity and thermal diffusivity of biological materials using thermographic camera(2014-01-01); ; - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Insight into the property and behavior of saccharides in amorphous state(2016-01-01); Gunasekaran, S.This study was aimed at investigating the calorimetric property and the mechanical behavior of amorphous saccharide system. A mixture of sucrose and maltodextrin was chosen as a model system. The mixtures were formulated with three different sucrose/maltodextrin (SC/MD) ratios. It was found that the T<inf>g</inf> increased with increasing maltodextrin concentration. Within the range of moisture content less than 4%, the average values of mid-T<inf>g</inf> were 73, 80 and 105°C for the systems with SC/MD of 7/3, 5/5 and 3/7, respectively. A strong plasticization effect of water on T<inf>g</inf> was also observed. A difference in mechanical behavior for large- and small-molecular weight saccharides was revealed with the small strain oscillatory shear test. Maltodextrin (large-molecular weight saccharide) contributed to an elastic or solid-like characteristic, which suggests that the molecular motions are primarily involved in stretching and bending of glycosidic linkages. The large number of strong glycosidic linkages present in maltodextrin might be responsible for the high rigidity of the system. In contrast, sucrose (small-molecular weight saccharide) contributed to a viscous or liquid-like characteristic. The findings suggest that type and number density of glycosidic linkages significantly define the mechanical behavior of amorphous saccharide systems. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, FTIR spectroscopic evaluation of sucrose-maltodextrin-sodium citrate bioglass(2017-09-01); Gunasekaran, SundaramA model bioglass system was composed with sucrose (SC), maltodextrin (MD), and sodium citrate (NaCit). Samples were prepared with different SC/MD ratios (7:3, 5:5 and 3:7, by mass) and NaCit/SC ratios (0, 0.1 and 0.2, by mole) at low (0.27–0.49 %wb) and high (2.83–4.4 %wb) levels of moisture content. The effects of system constituents were investigated using the Fourier transform infrared (FTIR) spectroscopy. Hydrogen bonding interactions analyzed by studying the OH-stretching absorption band in the FTIR spectra indicated that there was no noticeable effect of moisture on the bioglass. The matrix of the system with high concentration of MD was loosely packed. NaCit interacted with both SC and MD through carboxylic groups, as evidenced by the shifting of antisymmetric (ν<inf>as</inf>(COO<sup>−</sup>)) and symmetric (ν<inf>s</inf>(COO<sup>−</sup>)) stretching bands of carboxyl groups. However, NaCit tended to interact more strongly with SC rather than with MD as evidenced by the strongest hydrogen-bonded network observed in the system with highest concentrations of SC (i.e., SC/MD = 7:3) and NaCit (i.e., NaCit/SC = 0.2). - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Feasibility study on using evaporator condensate to subcool refrigerant in a vapor-compression refrigeration system(2018-08-14) - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Effects of heat transfer surface temperature on liquid egg yolk fouling(2024-01-01); ; - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Tensile properties of PLA/PBAT blends and PLA fibre-reinforced PBAT composite(2018-08-14); - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Mangosteen Pericarp Processing Technology to Create Economic Value and Reduce Biowaste(2024-07-01); ; This research comparatively investigates different mangosteen pericarp processing schemes. The experimental pericarp processing schemes were hot air drying (HAD; control), quick freezing/HAD (QF + HAD), slow freezing/HAD (SF + HAD), and slow freezing/freeze-drying (SF + FD). For freezing, the QF temperature was −38 °C for 2 h and that of SF was −25 °C for 2 weeks. For drying, the HAD temperature was 60 °C for 7 h. In the FD process, the primary and secondary temperatures were −20 °C and 50 °C for 48 h. The experimental results showed that the freezing method (i.e., QF and SF) affected the physical properties (moisture content, water activity, and color) of dried mangosteen pericarp. The antioxidant activities (DPPH and ABTS) of the SF + HAD scheme (28.20 and 26.86 mg Trolox/g DW of mangosteen pericarp) were lower than the SF + FD scheme (40.68 and 41.20 mg Trolox/g DW of mangosteen pericarp). The α-mangostin contents were 82.3 and 78.9 mg/g DW of mangosteen pericarp for FD and HAD, respectively; and the corresponding TPC were 1065.57 and 783.24 mg GAE/g DW of mangosteen pericarp. The results of this study suggest that the drying process had a negligible effect on bioactive compounds. Essentially, the SF + HAD technology is the most operationally and economically viable scheme to process mangosteen pericarp. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Rheological and microstructure evaluations of amorphous sucrose-maltodextrin-sodium citrate mixture(2017-01-01); Gunasekaran, SundaramRheological properties and the mechanical relaxation behavior of rubbery amorphous sucrose-maltodextrin-sodium citrate systems were studied at room temperature using the small amplitude oscillatory shear test in the frequency range of 0.1 - 150 Hz. The system with high sucrose concentration exhibited viscous-dominant relaxation, while the system with high maltodextrin concentration exhibited elastic-dominant relaxation. The addition of sodium citrate could retard molecular mobility presumably due to its molecular interaction with sucrose rather than with maltodextrin. The technique was capable to detect changes in molecular process even with a small variation in the matrix components. Evidences obtained with scanning electron micrographs suggested the possible effect of sodium citrate to interfere with molecular interactions in the system with high maltodextrin concentration, i.e. the system tended to be more brittle.