Optimal removal of iron impurities from kaolin by combination of Aspergillus niger & Bacillus subtilis

This study was carried out to remove iron from kaolin using a biological method by two different species of Bacillus sp. and the combination of A. niger isolated from pistachio skin & Bacillus subtilis and comparing them with the control sample. The experiments were carried out for Bacillus sp. at 30 °C and 25 °C and for the combination of A. niger & Bacillus subtilis at 27 °C. The concentration of dissolved iron increased with increasing temperature in the samples treated with Bacillus sp. X-ray fluorescence spectroscopy results of the samples at 25 °C showed a reduction of 31.1% in Fe2O3 and Fe content and a reduction of 37% at 30 °C after 28 days. Therefore, iron removal by Bacillus subtilis at 30 °C achieves better performance than at 25 °C. X-ray fluorescence spectroscopy results of the samples treated with the combination of A. niger & Bacillus subtilis show a decrease of 49% in Fe2O3 and Fe content at 27 °C after 14 days. The results of colour measurement showed that kaolin powder treated with the combination of A. niger & Bacillus subtilis at 27 °C had the highest degree of whiteness compared to other samples.

A novel camera colour characterisation model for the colour measurement of human skin

Fast track article for IS&T International Symposium on Electronic Imaging 2021: Color Imaging XXVI: Displaying, Processing, Hardcopy, and Applications proceedings.

COMPARING THE EFFECT OF LASER BLEACHING WITH HOME BLEACHING ON PAAN STAINED TEETH USING DIGITAL SPECTROPHOTOMETER

Introduction: The demand for tooth whitening has increased dramatically with the resulting development of new tooth whitening products and procedures. As it is a common scenario that the dentists come across paan stained teeth very regularly in dental practice, the need for this study is to compare if laser bleaching or three day home bleaching is effective for paan stained and give better treatment options for patients. Aim: To compare the effect of laser bleaching on paan stained tooth with home bleaching tooth using digital spectrophotometer Methodology: 20 extracted teeth were preserved in a solution of normal saline with 1% thymol crystals. The teeth were immersed in staining solution containing paan extracts for a period of two week. The specimens were evaluated for pre shades using VitaEasyShade. The stained specimens for paan respectively were divided randomly into 2 groups one for laser bleaching and other for home bleaching. POLA OFFICE + was applied on tooth and activated using the diode laser as per the manufacturer’s instructions for group 1. The bleaching was carried out with Philips Zoom Nitewhite for group 2. The second colour measurement of the specimens was made using VitaEasyShade. Conclusion: The results showed that laser bleaching was effective when compared to three day home bleach in paan stained teeth using digital spectrophotometer.