Sample is dissolved with nitric acid, hydrofluoric acid, remove smoke perchlorate silicon, fluorine and nitrogen oxides. In hydrochloric acid medium, first with most of stannous chloride reduction of ferric iron to ferrous iron, and then use the remaining TiCl3 quantitative reduction of Fe ^ 3 + Fe ^ 2 +, sodium tungstate as the indicator for the reduction endpoint, when the Fe ^ 3 + quantitative reduction of Fe ^ 2 +, the excess solution when a small amount TiCl3 enables sodium tungstate as an indicator of hexavalent tungsten (colorless) is reduced to blue pentavalent tungsten compound, so the solution was blue color. TiCl3 excess copper sulfate can be catalyzed, by dissolved oxygen and free oxygen in the air oxidation of the tungsten blue Chak faded, thereby reducing the impact of the elimination of excess TiCl3. Avoiding mercury determination of iron assay method using potassium dichromate oxidation classical excess TiCl3 error prone when introduced. Sulfuric acid mixed media, diphenylamine sulfonate as indicator, titrated with standard potassium dichromate solution, the amount of iron, and achieved satisfactory results. The relative standard deviation ≤0.30%.

Performed for insoluble ferromanganese silicon sample analysis, using nitric acid to dissolve most of the sample after dropping a small amount of hydrofluoric acid to dissolve the sample residue in the 680 nm wavelength colorimetric, test results show that the results of this assay with ICP method for the determination results, and the method is accurate and reliable. This method applies to the determination of ferromanganese 1.0% to 3.0% silicon content.

Evaluation of micro / nano (BMMSCs) effect of strontium carrier coating on bone marrow mesenchymal stem cell biological activity. Methods: titanium sheet is divided into three groups, A group: Smooth group (without any treatment, n = 24); Group B: hydrofluoric acid (HF) etching group (n = 24); Group C: HF acid magnetron sputtering eclipse + group (n = 27). SEM observation of titanium surface topography; X-ray spectroscopy (EDS) analysis of the surface element content; surface contact angle detecting titanium surface hydrophilic; ion release assay group C strontium ion release conditions. In the three groups were inoculated titanium surface BMMSCs, observe BMMSCs early adhesion; ALP activity assessment osteoblasts differentiation; MTT to detect cell proliferation. Results: 3 Group titanium sheet after different methods of treatment, group B forms micron-scale surface morphology; group C, forming a micro / nano-surface topography, and load the element strontium, and strontium ions can be released in the form; B, C group hydrophilicity, cell adhesion and proliferation were higher than group a and group B than in group C; ALP activity of cells on the surface of group C was significantly higher than group B. Conclusion: Micro / nano-contained strontium coating helps promote BMMSCs proliferation and osteogenic differentiation.