About 5 g of pristine natural graphite flakes was mixed with the volume ratio (1 30) mixture of concentrated nitric acid (98%) and hydrogen peroxide (30%).
The diet compromised a mix of 40% concentrated pellets and 60% straw nuts (Manor Farm Feeds, Oakham, UK) that had an estimated ME content of 12.6 MJ/kg and a crude protein content (nitrogen × 6.25) of 162 g/kg and 8.6 MJ/kg and a crude protein content of 69 g/kg dry matter, respectively.
Formation of a violet- blue color or greenish color was evidence that phenols presences [ 22, 23]. 1 gram of Vanillin was mixed with 100 ml of concentrated sulphuric acid after which 2 mls of the resultant solution was mixed with 2 mls of the plant extract.
The following reagents were applied: (1) sulfuric acid; (2) sulfuric acid-formaldehyde (1 mL of a 37% m/m solution of formaldehyde mixed with 50 mL of concentrated sulfuric acid); (3) sulfuric acid-nitric acid (1 mL of concentrated nitric acid mixed with 99 mL of an 80% v/v solution of sulfuric acid) [ 57].
One gram of MSW fine fraction/soil was mixed with 18 ml of concentrated HCl and 6 ml of concentrated HNO3 and moistened with a little deionised water.
Deionized water (30 mL) was mixed with 30 mL of concentrated hydrochloric acid (35%) to reach a total volume of 60 mL in a Teflon-lined stainless steel autoclave (100 mL volume).
Dissolve 1 gr of basic fuchsine in 200 mL of distilled water and heat to 80°C, let it cool down, and add 2 gr of sodium or potassium metabisulfite, mix, and incorporate 10 mL of concentrated hydrochloric acid or 2.5 mL of 1 N.
The transesterification was carried out using 50 ml of methanol and 0.2 ml of concentrated H2SO4 mixed together inside a 250-ml conical flask.
Each sample 0.5 mg was mixed with 2 ml of chloroform and 2 ml of concentrated sulphuric acid.
The extract was concentrated to ∼2 mL from ∼200 mL, and the concentrated extract was transferred to a glass test tube; ∼2 mL of concentrated sulfuric acid was slowly added and mixed.
