The arsenic- contaminated elemental arsenic is very low in toxicity, but the arsenic compound is poisonous. As2O3 is a kind of tri-arsenic compound. As3+ can bind to human cells to make metabolic disorders, nutrition disorders, harm nerves, and light appetite. , stomach disease, nausea, hepatomegaly, multiple dermatitis leading to cancer, and severe death. Arsenic contamination is a major source of arsenic in metal ore mining, smelting process and waste water pollution arsenic glass paint, pharmaceutical, paper production and coal combustion with TV or arsenic compound as the raw material gas, waste caused. In order to prevent arsenic pollution, the emission of arsenic-containing three wastes must be strictly controlled to ensure that the permissible emission standards are met. The arsenic content of domestic water should not exceed 0.04 mg/L, and the maximum allowable emission concentration of the “Three-Waste Emission Standards for Industrial Wastes†is 0.5 mg/L (in terms of As count).
For arsenic poisoning, symptomatic treatment of antidote such as sodium dimercaptopropane sulfonate or sodium dimercaptosuccinate can be used. The nature of arsenic is a gray semi-metal, commonly known as bismuth, which is a highly toxic substance. There are three allotropes of arsenic. The industry uses the most stable gray crystal at room temperature, which is bright like silver , has metallic properties, and is hard and brittle. The ash arsenic has a melting point of 817 ° C and a density of 5.73 g / cm 3 . Arsenic was heated in air to 200 ℃, phosphorescence appears. Burned at 400 ° C, a blue flame, the formation of arsenic trioxide smog, garlic flavor. Arsenic sublimes at 613 °C. Metal arsenic is insoluble in water but soluble in nitric acid and hot sulfuric acid. The arsenic-containing minerals in nature include realgar, orpiment, and stone. The use of arsenic as arsenic, lead alloy additions made projectile production, printing alloy, brass (condenser), battery grid, wear-resistant alloys, high-strength structural steel and other corrosion resistant steel. When prevented from dezincification brass containing traces of arsenic. Preparation of high-purity arsenic compound semiconductor material is gallium arsenide, indium arsenide or the like, the semiconductor material is silicon germanium and a doping element, these materials are widely used as diodes, light emitting diodes, infrared emitter laser or the like. Arsenic compounds are also used in the manufacture of pesticides, preservatives, dyes and pharmaceuticals.
High speed residential garage door
Transparent aluminum (imitation stainless steel ) is widely used for commercial purposes , car sales, cleaning and service stations, and requires good lighting , high perspective of the building
Horizontal and vertical door frame are anodized polished aluminum die molding (or grilled white acrylic enamel processing) , the overall thickness of 50mm,
Using single or double glass 3mm thick glass DSB, or thicker , double insulated SSB glass , with a sturdy vinyl sealing strip seal
Industrial flooring can be doors , aluminum sheet or other sheet metal treated
Other accessories refer to industrial sliding doors
garage door , doors, overhead door,intelligent garage door,high speed door
SHENZHEN HONGFA AUTOMATIC DOOR CO., LTD , https://www.hongfahsrd.com