Objective: To determine the effects of pH, fluoride (F-) and hydrofluoric acid(HF) concentration on the release of nickel (Ni2 +) and titanium (Ti4 +) ions. NiTi, RhN (TiNiTi) and nitride (NNiTi) coatings were impregnated once a week in a remineralizer for 5 minutes and then immersed in artificial saliva. The ion release was recorded at 3, 7, 14, 21 and 28 days. Pearson correlation and linear regression were used for statistical analysis. Ni2 + release from NiTi and NNiTi lines was positively correlated with hydrofluoric acid (r = 0.948 and 0.940, respectively); for RhNiTi, the correlation was low and negative (r = -0.605; p <0.05). The prediction of Ti4 + release is significant for NiTi (r = 0.797) and NNiTi (r = 0.788; p <0.05) lines. And F- is low; for pH is not significant. hydrofluoric acid predicts the release of ions from NiTi lines over the pH and F- of the prophylactic agents.

Describes a rapid and efficient sample preparation method in view of the isotope ratio measurement which allows the eleven elements involved as “parent”or as “daughter” isotopes to be used in the six radiometric isotopes used as a timer and tracer for the earth System separation, and environmental science. The solution is based on a small extraction column, used alone or in series, through a single nitric acid solution without any intermediate evaporation step. (L resin, Ln resin, RE resin, and Ln resin for separating Sr and Pb, LREE, then La-Ce-Nd-Sm, Lu (Yb) and U), and a commercially available extraction resin (Sr resin, TRU resin, Additional internal preparation of the resin for the separation of Rb. A simplified scheme was proposed for samples that only need to separate Sr, Pb, Nd and hydrofluoric acid. The adverse effects of troublesome main elements (Fe3 +, Ti) are avoided by masking with ascorbic acid and hydrofluoric acid, respectively. A typical recovery rate is achieved in the range of 85-95%, the program blank is 10-100 pg, and the amount of analyte being treated is negligible. The isolated fractions are suitable for high precision isotopic ratios measured by TIMS or MC-ICP-MS, such as through international reference for several basalt compositions for 87Sr /86Sr, 208, 207, 206Pb /204Pb, 143Nd /144Nd, 176hydrofluoric acid /d The repeated analysis of the material proves that 177Hf and 230Th / 232Th. The concentration data can be obtained by adding and equilibrating the sample with a suitable isotopic tracer before the start of the separation process and finally measuring the isotopic ratio modified by the isotope dilution process.