Nanodrop nd 1000 v 3.3.1 spectrophotometer

The suspended pellet following GE incubation for varying time periods was characterized using a Nanodrop ND-1000 v 3.3.1 spectrophotometer, (Nanodrop Technologies, Inc., Wilmington, USA). The absorbance was scanned from 220–700 nm. Fourier-transform infrared spectroscopy (FTIR) (Shimadzu FTIR-8300 spectrometer, San Diego, CA, USA) of the recovered product and of the solid wastes prior to and subsequent to treatment was done using KBr pellets. Field emission scanning electron microscopy (FE-SEM) (JEOL, JSM-5410LV) was used to image the synthesized product. The morphological changes on the shells and squid pens prior to and subsequent to incubation with the extract were imaged using an inverted microscope, Axiovert 2000, Carl Zeiss, Germany. The chitosan recovered from interaction with marine shell waste was characterized using a JEM-1400PLUS, transmission electron microscope (TEM), JEOL USA, Inc. Peabody, MA, USA. For calculating the degree of deacetylation (DDA) to confirm the chemical identity of chitosan using FTIR spectra, several procedures and equations are described in literature^{53 (link),54} . These equations were derived on the basis of calibration curves, and the calculation procedures are based on absorbance ratios of various spectral bands^{55 (link),56 (link)}. The equation^{57 (link)} used in this study is listed below. $$\mathrm{DA}[\%]={\mathrm{A}}_{1655}/{\mathrm{A}}_{3450}\times 115$$

The extracts were characterized using a Nanodrop ND-1000 v 3.3.1 spectrophotometer, (Nanodrop Technologies, Inc., Wilmington, USA). The absorbance was scanned from 220–700 nm.

The turmeric smudge (TS) was characterized for the presence of carbon nanomaterial using a Nanodrop ND-1000 v 3.3.1 spectrophotometer, (Nanodrop Technologies, Inc., Wilmington, USA). The absorbance was scanned from 220–700 nm. The NC@TS was characterized using a JEM-1400PLUS, transmission electron microscope (TEM), JEOL USA, Inc. Peabody, MA, USA. Further characterization was done using FTIR (Shimadzu FTIR-8300 spectrometer, San Diego, CA, USA) using KBr pellets. For FTIR, KBr was added directly into the beaker containing the smudge collected from the turmeric fumes, and then the smudge was scraped out with mixing alongwith the KBr powder. When the KBr powder took up the turmeric smudge, it turned grayish. After this, it was ground and pellets were made as per routine FTIR analysis. FTIR of the carbon particles extracted via centrifugation (NC@TS) was conducted too. In this case the samples were dried in an oven and the powder was used for analysis. Energy Dispersive X-ray analysis (EDAX) was used to confirm the chemical composition of the TS using an FE-SEM ((JEOL, JSM-5410LV).