![]() The most important parameters of the performance of optical disinfection equipment. Because of the equipment size requirements, the general irradiation time is only a few seconds, so the UVC output intensity of the lamp becomes a measure of UV. Ultraviolet irradiation dose refers to the amount of ultraviolet radiation at a specific wavelength when reaching a certain bacterial inactivation rate: irradiation dose (J/m2) = irradiation time (s) XUVC intensity (W/m2) The higher the irradiation dose, the higher the disinfection efficiency. These are the culprits in premature skin aging, wrinkles, sunburn, eye damage and skin cancer (like squamous cell carcinoma and basal cell carcinoma). UVA and UVB rays are the two that penetrate the ozone layer and reach the Earth from the sun. As the lamp ages, it will lose 30% less than 50% of the intensity. The sun emits three different types of UV radiation: UVA, UVB and UVC. At the same time, it is also subject to the output energy of ultraviolet light, which is related to the type of lamp, light intensity and use time. So we won't be talking about UVC in this. The bactericidal effect is determined by the irradiation dose accepted by microorganisms. There are 3 types of Ultra Violet (UV) rays from the sun: UVA, UVB and UVC. In addition, the sterilization rate is very slow, it often takes several hours to play a bactericidal effect, in the actual project for a few seconds of hydraulic retention (irradiation) time, this part is actually an invalid ultraviolet part. In terms of bactericidal rate, UVC is within the range of microbial absorption peak and can kill viruses and bacteria by destroying the DNA structure of microorganisms in ls, while UVA and UVB are in the range of microbial absorption peak. Only UVA and UVB can reach the earth's surface through ozone protection and clouds. The experimental results show that the effective wavelength range of ultraviolet sterilization can be divided into four different bands,: UVA (400~315nm), UVB (315 ~ 280nm), UVC (280~200nm and vacuum ultraviolet (200 ~ 100nm). It results in the death of growing cells and / or the death of regenerated cells or the inability to reproduce, so as to achieve the effect of sterilization and disinfection. The effect of ultraviolet radiation on nucleic acid can lead to the breaking of bonds and chains, cross-linking between strands and the formation of photochemical products, etc., thus changing the biological activity of DNA. The energy of ultraviolet photons is absorbed by the base pair in DNA. Ultraviolet disinfection lamp can destroy the molecular structure of DNA (deoxyribonucleic acid) or RNA (ribonucleic acid) in microbial cells by ultraviolet light of appropriate wavelength.
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