ICA – POSTER 406 Acoustics and Dielectric properties of Borassus Flabellifier ‘ BF ’ with frequency at 308 K .
Dielectric properties of Borassus Flabellifier ‘BF’ wood were carried out by authors with frequency at room temperature 308K. The wood section is taken from ma le BF tree and female BF tree from where the natura l j ice is collected over night. A large variation occurs at f requencies less than 10 Hz. at room temperature 308 K.The dielectric constant decreased as frequency increase d from 1 Hz to 4.0 x10 Hz. The minimum peak value of the dielectric loss tangents shifted towards higher fre quencies at room temperature 308K. Very low dielect ric conductivity has been observed. Characterization of the samples was made by scanning electron microsco pe (SEM) Model JEOL JSM5400. Results shows that the dielectr ic properties are slight different in male and fema le BF wood considerably. The variation of the dielectric const a t in different wood structures is correlated at r oom temperature with the frequency variations in a way the received signal strength. Acoustics measurement were carrie d out in our laboratory using Ultrasonic Interferometer by NDT t echnique and the dielectric measuring device used i n this study at UGC-DAE Consortium for Scientific Research Centr Indore (M.P.) India. In this study the drying of wood done by microwave energy using a continuous microwave dr i r was compared to that by conventional method.
Effects of Ultrasonic Detection Modes on the Longitudinal Ultrasonic Wave Transmission in Domestic Plantation Lumber
The performances of different ultrasonic detection applications on the longitudinal wave propagation in Japanese cedar (Cryptomeria japonica) and China fir (Cunninghamia lanceolata var. lanceolata) lumber were evaluated in the study. Results showed that insignificant differences among longitudinal ultrasonic wave velocities measured by transducers from 40 to 1000 kHz were found using the direct transmission method. The average wave velocities were 5074 and 6003 m s^(-1) for Japanese cedar and China fir, respectively. The longitudinal ultrasonic wave velocity obviously decreased with both the surface transmission method and semi-direct transmission method under 500-and 1000-kHz conditions. Good correlations, i.e., R^2 values of between 0.92 and 0.94, among the measured longitudinal ultrasonic wave velocities in the 3 detection methods with a 40-kHz transducer were obtained. Longitudinal ultrasonic wave velocities of wood measured with the different-shaped transducers and coupling methods also had good correlations, with R^2 values of between 0.95 and 0.99. The velocity measured with the flat transducer was 8.8~11.1% higher than that with the tapered transducer. The modulus of elasticity of wood can be estimated using longitudinal ultrasonic wave velocities measured by the 3 different detection methods with R^2 values of between 0.79 and 0.85 for Japanese cedar and China fir. It is expected that ultrasonic detection can be applied to the derivation of allowable strengths of structural lumber from Taiwanese plantations and for field inspections.
Novel polymeric hydrogel composites: Synthesis, physicochemical, mechanical and biocompatible properties
In this research study, novel hydrogel composite films were constructed using different ratios of poly (vinyl alcohol) (PVA)/kappa-carrageenan (KC) (PVA90/KC10%, PVA80/KC20%, PVA70/KC30%, PVA60/KC40%) crosslinked with glutaraldehyde (0.025%) and investigated their physicochemical characteristics such as mechanical, thermal, morphological, swelling behaviour, and cell viability. SEM and FTIR revealed that surface morphology changed to heterogeneous and the presence of molecular interaction among the polymers. PVA90KC10 and PVA60KC40 exhibited smaller and larger pores on surface respectively. The change in the proportion of PVA and KC also triggered the tensile strength (Ts) of the film and the highest Ts observed were 21.60 MPa for PVA60KC40. Moreover, the thermal analysis showed three-phase degradation, and an increase in KC40 concentration results inversely proportional to a decrease in the rate of thermal degradation. Further, swelling and in-vitro biodegradation study confirmed the enhanced perseverance of water uptake for PVA60KC40 (286%) due to pores structure of the hydrogel film and PVA and KC alone degraded faster as compare to other films results suggested higher concentration of PVA90KC10 showed lower degradation rate and highest for PVA60KC40 about 6% and 22% respectively. Further, the cell viability was studied with MTT assay method by using NIH3T3 and HEK-293 cells for biocompatibility study revealed NIH3T3 cells were more biocompatible than HEK-293 and cell viability percent for PVA60KC40 showed the highest cell attachment about 99%. Overall corroborating data obtained from the study attested to the average swelling, appreciable mechanical characters, good interaction between molecules, and cell viability of the constructed PVA/KC hydrogel film, these all characters pave to be used as a potential template for biomedical applications such as tissue engineering and drug delivery.