basic introduction 氦 (Old translation 氜) is a chemical element, its chemical symbol is He, its atomic number is 2, is a colorless inert gas, and emits deep yellow light when discharged. At room temperature, it is a very light, colorless, odorless, tasteless monoatomic gas. Helium is the most difficult to liquefy of all gases and is the only substance that cannot be cured at standard atmospheric pressure. The chemical nature of hydrazine is very inactive and it is difficult to react with other substances under normal conditions.氦 is the second most abundant element in the universe, accounting for 24% in the Milky Way. Application field Helium is widely used in military, scientific research, petrochemical, refrigeration, medical, semiconductor, pipeline leak detection, superconducting experiments, metal manufacturing, deep sea diving, high-precision welding, optoelectronics production. 1. Low-temperature cold source: Using the low boiling point of liquid helium at -268.9 °C, liquid helium can be used for ultra-low temperature cooling. Ultra-low temperature cooling technology has a wide range of applications in the field of superconducting technology. Superconducting materials need to exhibit superconducting properties at low temperatures (about 100K). In most cases, only liquid helium can easily achieve such extremely low temperatures. . Superconducting technology has a large application in maglev trains in the transportation industry and MRI equipment in the medical field. 2, balloon inflation: because the density of helium is much smaller than air (the density of air is 1.29kg / m3, the density of helium is 0.1786kg / m3), and the chemical properties are extremely inactive, safer than hydrogen (hydrogen can be burned in the air It may cause an explosion. Helium is often used to fill gas in spacecraft or advertising balloons. 3. Inspection and analysis: The superconducting magnet of the nuclear magnetic resonance analyzer commonly used in instrumental analysis needs to use liquid helium to cool down. In the gas chromatographic analysis, helium gas is often used as a carrier gas, and the helium gas permeability is good and non-flammable. Used in vacuum leak detection, such as helium mass spectrometer leak detectors. 4. Protective gas: Utilizing the inactive chemical properties of helium, helium is often used as a protective gas for welding metals such as magnesium, zirconium, aluminum and titanium. 6. Other aspects: Helium gas can be used as a high-vacuum device, and the nuclear reactor is used as a pressurized gas for transporting liquid propellants such as liquid hydrogen and liquid oxygen on rockets and spacecraft. Helium is also used as a cleaning agent for atomic reactors, a mixed gas for breathing in the field of marine development, a gas filled with a gas thermometer, and the like. Precautions This product is a non-combustible gas hazard number: GB 2.2 class 22007. UN NO.1046; IMDG CODE page 2144, class 2.2. (Compressed) GB 2.2 Class 22008. UN NO.1963; IMDG CODE 2144, page 2.2. (liquefied). Helium is an inert gas. At high concentrations, the partial pressure of oxygen can be lowered and there is a risk of suffocation. When the concentration of strontium in the air increases, the patient first has accelerated breathing, inattention, and ataxia; followed by fatigue, irritability, nausea, vomiting, coma, convulsions, and death. Liquid sputum contact with the skin can cause severe frostbite. Packed in 6m3 cylinders or 2L glass bottles. The glass bottle is protected by a wooden box or carton. Store in a cool, dry warehouse. It can be transported as ordinary goods. Handle gently during loading and unloading to prevent damage to the package. Water and various fire extinguishers can be used to save the fire.
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Beijing Meihua Instrument analyzes the application field of helium