In this study, zinc borate hydrate (Zn 3 B 6 O 12 · 3.5H 2 O) was synthesized from zinc oxide (ZnO) and boric acid (H 3 BO 3 ) via a novel method of ultrasonic irradiation. X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR) and Raman spectroscopy were used to characterize the synthesized products. Scanning electron microscopy (SEM) was used to determine the effects of reaction time and reaction temperature on the morphology of the products. Thermal dehydration kinetics were studied using thermal gravimetry and differential thermal gravimetry analysis (TG/DTA). The Doyle and Kissinger non-isothermal kinetic methods were used to analyse the TG/DTA data. The XRD results confirmed the successful synthesis of Zn 3 B 6 O 12 · 3.5H 2 O at a range of reaction temperatures and times. Additionally, FT-IR and Raman analysis of the products identified peaks specific to zinc borate. Using the methods of Doyle and Kissinger, the activation energies of thermal dehydration of zinc borate were found to be 341.61 kJ/mol and 390.17 kJ/mol, respectively.

Recently, sonochemistry has been used for the synthesis of inorganic compounds, such as zinc borates. In this study using zinc sulphate heptahydrate (ZnSO4·7H2O) and boric acid (H3BO3) as starting materials, a zinc borate compound in the form of Zn3B6O12·3.5H2O was synthesized using an ultrasonic probe. Product’s characterization was carried out with using X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR) and Raman spectroscopy. Zinc borate compound’s chemical bond structure was observed with Raman and FTIR. From the XRD results it was seen that Zn3B6O12·3.5H2O can be quickly synthesized upon heating at 80°C and 85°C (55 min) or 90°C (45 min) in very high yield (>90%). The minimum particle size obtained was ~143 μm from the SEM results. Zinc borate compound was synthesized at a lower temperature in less time than other synthesized zinc metal compound in literature.

The main purpose of this study was to research the influence of different drying methods on the physical and quality properties of dried shrimps. Shrimps were dried with conventional methods at 60, 70 and 80?C between 330 to 210 minutes and 190 to 110 minutes, in an oven and vacuum oven respectively. Drying time is shortened with the use of vacuum pump. The drying kinetics of the shrimp were studied, and effective moisture diffusion and activation energy were calculated for both methods. The Alibas model and the Midilli & Kucuk model provided the best experimental data with a high coefficient of determination (R2) for oven and the vacuum-oven techniques, respectively. The final dried products were characterized by investigating the colour characteristics, heavy metal content and by carrying out protein analyses. Rehydration ratio was also determined for the dehydrated shrimps. Drying conditions affected the colour features so that shrimps dried in ovens and vacuum ovens showed an increase in brightness and yellowness values and decrease in redness values. The concentration of As, Pb, Cd, Hg, Cu, Zn and Fe in the dried shrimp were within acceptable limits. The protein content of dried shrimp (~85%) is higher than undried shrimp (~20%).