New Progress in Preparation Methods of two-dimensional graphene structure MXene class, performance and applications, proposed a relatively modest production method using lithium fluoride and hydrochloric acid instead of highly corrosive hydrofluoric acid preparation of the novel transition metal carbides or carbonitrides. Analysis of the performance of the system described in the electrical, thermal stability and mechanical properties. Introduction of this new material is widely used, focusing on its application in the field of adsorption, catalysis and the like. That with the improvement of preparation method on the microstructure and in-depth understanding of this material can be used in more important areas.

Using high-pressure sealed acid dissolve sample, inductively coupled plasma mass spectrometry (ICP - MS) Determination of rock in a variety of trace, trace element analysis is a method commonly used in geological analysis, but in the granodiorite sample analysis, due to the presence of insoluble zirconium forming minerals (zircon, rutile), there will be zirconium dissolution rate low phenomenon. In response to this phenomenon, this study adds to the rush of silicon pretreatment process, increase hydrofluoric acid the amount of the introduction of fluoride ions in the solution medium zirconium fluoro-complex ion is formed to improve the stability of zirconium, zirconium will improve the dissolution rate to about 95%, to achieve an accurate determination of granodiorite trace zirconium in this process the precision (RSD, n = 11) less than 5%, the detection limit was 0. 052 μg / g. applied to the analysis Karamay granodiorite zirconium, the measured value with sodium peroxide, lithium metaborate alkali fusion and the measured value of X-ray fluorescence spectrometry has a good consistency, and small matrix effect, low detection limit, measured but also to meet a variety of other trace elements lithium, beryllium, scandium, at the same time.

Silica were measured using potassium fluosilicate volumetric method. First, ashing silica milk or milk powder, and then by caustic communion, form soluble silicates, soluble silicates and precipitated a lot of potassium chloride in the presence of fluorine ions generated fluorine potassium silicate. Silicon potassium fluoride precipitated in boiling water with the decomposition of hydrofluoric acid. Sodium hydroxide standard solution titration, calculated indirectly silica content. The recovery process in between 93.40% ~ 99.2%, RSD≤2.06% (n = 8). The detection limit of 0.5 mg / 100g. The method is simple, low cost measurement, high accuracy and can be used for quantitative determination of silica milk and dairy products silica.