Monthly Archives - August 2022

Brief analysis of calcium tungstate

From the chemical composition point of view, with sodium tungstate (Na2WO4) and potassium tungstate (K2WO4) is different from the cation in calcium tungstate (Ca2+) is alkaline earth metal, so they are slightly different in structure, physical and chemical properties, production process and use. Note: Sodium and potassium are both alkali metals By definition, calcium tungstate, also known as “artificial tungstate”, is a tungstate consisting of regular divalent metal calcium ions (Ca2+) and tungstate ions [(WO4)2-]. It is a typical self-activating [...]

Analysis of ammonium paratungstate

Also a kind of inorganic metal tungsten compound, ammonium paratungstate and ammonium metatungstate have certain differences in performance, production technology and application. First, the former is insoluble in water, the latter is easily soluble in water, and the aqueous solution is quite stable; Second, the former is the main raw material for the production of the latter; Third, the former is mainly used to produce tungsten products, the latter can be used to produce tungsten products, but also can [...]

Preparation of superfine tungsten carbide

In recent years, the methods of preparing ultrafine or nanometer WC powder mainly include: mechanical alloying, direct reduction carbonization, sol-gel, gas carbonization, fixed-bed chemical vapor method, plasma method, etc. Mechanical alloying Grahame, etc by mechanical alloying method, first the W powder mixes with C powder by atomic ratio 1:1, in the steel tube and argon gas is piped in, and then choose a diameter of 12 mm WC grinding ball, the ball material ratio of 18:1, finally in high-energy ball mill [...]

Preparation of boron carbide nano powder and its epoxy coating

Boron carbide is a kind of super-hard compound in nature. In normal state, its hardness is second only to diamond and cubic boron nitride, and it is hardest at high temperature (about 1000 degrees Celsius). At the same time, boron carbide is a kind of P-type semiconductor with excellent thermal conductance. Most importantly, it is particularly resistant to acid and alkali corrosion. Because of various advantages, the industry has been trying to use boron carbide as a coating material. But [...]

Silicotungstic acid can be used as a launching agent for isotope analysis of trace strontium

Strontium isotope ratio (87Sr/86Sr) is widely used in the fields of earth science, astrochemistry, environmental chemistry, food origin traceability, archaeology and so on. Thermoionization mass spectrometers (TIMS) have been regarded as the benchmark technique for 87Sr/86Sr ratio analysis since the 1960s. This method not only has excellent accuracy, but also has extremely high sensitivity. Excellent sensitivity is the prerequisite for high precision 87Sr/86Sr ratio analysis of ultramicro samples. The key to improve the sensitivity lies in the selection of [...]