The sample tray (sample dish) is a consumable in the thermal analysis experiment of the thermal analysis instrument, the English name samplepan . The first thermal analysis method used at the end of the 19th century was the thermocouple measurement method. From then on, the sample tray (sample dish) appeared in the laboratory along with the thermal analysis instrument and was widely used in various fields. The sample tray (sample dish) is suitable for DSC differential scanning calorimeter, SDTA differential thermal analyzer, TGA thermogravimetric analyzer and other thermal analyzers, and is an indispensable experimental consumable in thermal analysis experiments. In the experiment, the sample tray mainly plays the role of holding the sample (the object to be tested), and can be divided into a sealed sample tray and a non-sealed sample tray according to the experimental characteristics. The experimental use of the sample tray can be divided according to the solid, gas and liquid of the experimental object. The sample tray has many different materials. It can also be divided according to the material when distinguishing the sample tray. It can be divided into metal materials and oxidized materials and quartz materials. Among them, the metal can be subdivided into metal aluminum, stainless steel, nickel metal, and platinum-rhodium alloy. The oxidized material can be divided into two types: alumina and zirconia.
1. Aluminum sample tray, the main material is metal aluminum, metal aluminum is easily soluble in dilute sulfuric acid, nitric acid, hydrochloric acid, sodium hydroxide and potassium hydroxide solution, difficult to dissolve in water. The relative density is 2.70. The temperature of 660 ° C. The boiling point is 2327 ° C. Because of these characteristics, it is relatively cheaper as the material of the sample tray. The more common brands in foreign countries are TA, PE, METTLER, Shimadzu, NETZSCH, and STATRAM. The domestic production is mainly produced by Shanghai cypress laboratory equipment. Due to the metal characteristics of aluminum, the experimental temperature of aluminum sample tray is probably controlled at 550 °C, and the metal aluminum has the characteristics of elongation, so it is easy to seal. It can be used for solid and liquid experiments, but it is all once. Sexual laboratory supplies. The price of aluminum sample trays produced abroad is relatively high (the price of the plate + cover) is about 30 yuan. Domestic prices are cheaper, ranging from 4 to 5 RMB!
2. Stainless steel sample plate, stainless steel (Stainless Steel) is the abbreviation of stainless acid-resistant steel, resistant to air, steam, water and other weak corrosive media or stainless steel is called stainless steel; and ordinary stainless steel is generally not resistant to chemical media corrosion Therefore, the use of stainless steel as a material to make a sample tray is relatively small. Shanghai Dibo Company produces two types of sample trays. One of them is a sample tray with a stand. The general experimental temperature is controlled at 300 ° C, used for high pressure experiments! The market price is around 9 yuan!
3. Metal nickel sample disk, nickel is almost silver-white, hard and malleable and has ferromagnetic metal elements. Because nickel is not particularly stable in chemical properties, it can react with many substances, so it is not a lot of samples. The material of the disc. The experimental temperature is generally controlled at 700 ° C is more suitable. It is a general-purpose sample tray (both liquid solids). The market price is generally around 7 yuan!
4. Platinum-rhodium alloy, which is a platinum-based binary alloy containing ruthenium, which is a continuous solid solution at high temperatures.铑 can improve the thermoelectric potential, oxidation resistance and acid corrosion resistance of platinum to platinum, so it is very suitable for making sample trays, but because it is a precious metal, it is relatively expensive. However, due to the physical and chemical properties of the platinum-rhodium alloy, the platinum-rhodium alloy sample pan is reusable and is still widely used. The experimental temperature of the platinum-rhodium alloy is generally controlled at 1600 ° C. The price of a set with spider orchids is as high as 1,300 yuan. The price without the spider plant is about 600 yuan.
5. Alumina sample tray, alumina has good chemical stability and thermal shock resistance, and has high thermal conductivity, so it is widely used in the production of sample trays. Because of his high chemical stability, it is a sample tray that can be used repeatedly, and it is not expensive compared to platinum-rhodium alloys, so many experimenters are willing to use the sample tray of this material as a laboratory consumable. The sample temperature of alumina can be controlled up to 1750 °C. The market price is about 6 yuan.
6. Zirconia sample tray, zirconium dioxide (chemical formula: ZrO2) is the main oxide of zirconium, usually white odorless and odorless crystals, difficult to dissolve in water, hydrochloric acid and dilute sulfuric acid. It usually contains a small amount of cerium oxide. It is chemically inert and has high melting point, high electrical resistivity, high refractive index and low thermal expansion coefficient, making it an important high temperature resistant material, ceramic insulating material and ceramic sunscreen. It is also the main raw material for artificial drilling. It can be seen that zirconia has special chemical properties, and is insoluble in water, hydrochloric acid and dilute sulfuric acid, and has high temperature resistance. Therefore, the sample plate made of zirconia is also inherited the advantages of zirconia, stable and high temperature resistant. It can be used repeatedly and is easy to clean. The experimental temperature can be as high as 2200 °C. However, since the zirconia material is relatively expensive, the price of zirconia is relatively high. The general market price is about 17 yuan.
7. Quartz sample tray, the main material is refined quartz sand. Therefore, the sample tray made of quartz material is transparent, high temperature resistant and easy to clean, and is often used in adsorption analysis experiments. The experimental temperature can reach 1000 °C! The market price is generally 35 yuan.
Royal Jelly is also called Bee Milk. The fresh royal jelly is slightly ropy milk paste substance; it is the excretive mixture of nutrition gland and maxilla gland of the head of little worker bee. The worker bees use this to feed the 1-3 days` worker bee larva and drone larva, 1-5.5 days` queen bee larva and queen bee in the oviposition period. The royal jelly is the biologic product containing very complicated active elements which contains almost all the nutrition elements required by the growth of the human body.
Royal Jelly,Natural Royal Jelly,Healthy Royal Jelly,Organic Fresh Royal Jelly
Easy Food (Jiaxing) Co., Ltd. , https://www.jxeasyfood.com