Triplicate 1-mL samples were acidified with 20 [micro]L of
orthophosphoric acid, and triplicate 1-mL original samples were frozen at -20[degrees]C for later analysis of volatile fatty acid (VFA) and ammonia nitrogen (NH3-N), with the methods as described by Hu et al [18].
Reagents used in the study were low viscosity sodium alginate 99.5% from brown algae, Reagent-Plus 99.5% NaSA, calcium chloride,
orthophosphoric acid, acetic acid, and acetonitrile (Sigma Chemical Co, St Louis, MO, USA).
Samples were etched using 35% (v/v)
orthophosphoric acid for 15 s to remove the smear layer and etch the surface, washed with distilled water and then dried with tissue paper.
The surface was roughened with 37%
orthophosphoric acid, and bonding agents were applied on the tooth surface.
-
orthophosphoric acid ([H.sub.3]P[O.sub.4]) (POCH S.A.),
Orthophosphoric acid ([H.sub.3]P[O.sub.4]), magnesium nitrate (Mg[(N[O.sub.3]).sub.2]), aluminum sulphate ([Al.sub.2][(S[O.sub.4]).sub.3]), sodium hydroxide (NaOH), sulphuric acid ([H.sub.2]S[O.sub.4]), aluminum hydroxide (Al[(OH).sub.3]), calcium nitrate tetrahydrate (Ca[(N[O.sub.3]).sub.2]*4[H.sub.2]O), and 1-butyl-3-methyl-imidazolium hexafluorophosphate ([BMIMPF.sub.6]) were used.
This layer is then etched in an
orthophosphoric acid bath.
Celzard, "Study of the decomposition of kraft lignin impregnated with
orthophosphoric acid," Thermochimica Acta, vol.
The elution was carried out at room temperature in a linear gradient using a system consisting of a solution of 10 mM K[H.sub.2]P[O.sub.4] adjusted with
orthophosphoric acid to pH 2.4 (eluent A) and acetonitrile (eluent B).The flow rate of the mobile phase was 1 ml/min.
The fractured component and tooth structure of maxillary left lateral incisor were cleaned and acid etched with 37%
orthophosphoric acid gel for 20 seconds.
The method was developed employing mixture of mobile phase consisting of 0.02 M potassium dihydrogen phosphate buffer and acetonitrile (45:55), pH was adjusted to 2.7 using 50%
orthophosphoric acid and pumped thorough chromatographic system at a flow rate of 1 ml/min.
