What is the principle of glow in the dark? What is the principle of glow in the dark

Phosphors"Luminous revelations.

In order to understand the chemical composition of phosphor, we first thought of the luminescence of glowworms, and the luminescence principle of glowworms mainly includes the following series of processes.

Photoproteins Photogenic enzymes contain oxygenated photoproteins (emit green light).

Oxygenated photoproteins H2O photoproteins.

This is the reason why glowworms can continue to emit light, and the light flashes and flashes, it is worth noting that the green light emitted by glowworms is a kind of"Cold light"The result is a 97% conversion rate.

Secondly, we also pay attention to the luminescence of luminescent plastics, which are mainly mixed with some radioactive substances in ordinary plastics, such as 14C, 35SR, 90SR and Na, Th and luminescent materials ZNS, CAS, these sulfides are excited and emit visible light (cold light) under the irradiation of radioactive light.

The chemical composition of phosphors is deepened from vague silicate and tungstate, single elements BA and SR to the standard chemical formula, and its chemical composition is:

Category: Chemical Formula.

Color density.

Red Pink Y2O3: EU White.

Green Pink CEMGL11O19: TB White.

Blue Pink Bamgal10O17: EU White.

Bimodal Blue Pink Bamga10O17: (EU, MN) White.

The composition of the upconversion phosphor, that is, the infrared excitation phosphor, is:

Chemical Composition: YeryBF3

Appearance: white inorganic powder.

Grain size: 30 nm

Excitation wavelength: 980nm

Glowing color: green.

Characteristics: high light transmittance, high solvent resistance, acid and alkali resistance.

Several ways to deal with phosphor hazards.

When mercury vapor reaches 3 mg, it can cause chronic poisoning within 2 to 3 months; Acute mercury poisoning can be induced at milligram levels, and if the amount reaches 20 milligrams, it will directly lead to the death of animals.

Once mercury enters the human body, it can quickly diffuse and accumulate into tissues and organs such as kidneys and chests, chronic mercury poisoning can lead to mental disorders, autonomic disorders, acute symptoms often headache, fatigue, fever, redness, swelling and soreness of the gums in the oral cavity and digestive tract, rotten bleeding, loose teeth, etc., some ** red spots, papules, a small number of kidney damage, individual kidney pain, chest pain, dyspnea, cyanosis and other acute interstitial pneumonia.

If mercury is not properly stored and disposed of, it will also cause great harm to the ecological environment, it enters the environment in various forms, directly pollutes soil, air and water, and then enters the human body through the food chain, endangering people's healthy life, so it must not be discarded everywhere.

If the indoor fluorescent tube is broken, 1 gram of iodine can be added to alcohol and then fumigated or directly dispersed on the ground with 1 gram of cubic meter of iodine for 8 12 hours, so that the volatilized or sublimated iodine and mercury in the air generate involuntary mercury iodide (hg+i2 hgi2). To reduce the concentration of mercury vapor, contaminated floors can also be rinsed with 5% 10% ferric chloride or 10% bleach.

There are two types of glow-in-the-dark things, one is that luminescent materials are added to the manufacturing process, and the light emitted by it can be seen in the dark. However, it has a bad impact on the human body, and there are many military products of this kind of thing. Another type of light storage material that is added is the light storage material that absorbs and stores the light that hits its surface and releases it when it is dark, which is what we commonly see.

The principle of luminous powder luminescence is that when the light hits certain atoms, the energy of the light causes some electrons around the nucleus to jump from the original orbital to the higher energy orbital. The first excitation singlet or the second excitation singlet is unstable, and when the electrons return from the first excited singlet to the ground state, the energy will be released in the form of light, resulting in fluorescence.

Luminous powder first absorbs all kinds of light and heat, converts it into light energy storage, and then automatically emits light in the dark, realizes the luminescence function by absorbing various visible light, and can be recycled an unlimited number of times, especially for short-wave visible light, sunlight and ultraviolet light (UV light) below 450 nanometers.

Uses of Luminous Powder:

People use the characteristics of luminous powder to shine for a long time in actual life, make a weak lighting source, have a special use in the military department, and apply this material to various switch signs on aviation instruments, clocks, windows, machines, door handles, etc., and can also be pressed into various symbols, components, supplies (such as power switches, sockets, fishing hooks, etc.) together with various translucent plastics.

These light-emitting parts continue to glow at night or when they get up after an unexpected power outage or lightning, allowing people to distinguish the direction of their surroundings and bring convenience to their work and life. The ultra-fine particles of luminous materials are incorporated into textiles to make the colors more vivid, and children can wear luminous textiles to reduce traffic accidents.

The principle of noctilucent light is that when light hits certain atoms, the energy of the light is madeNucleusSome of the surrounding electrons have jumped from their original orbitals to higher energy orbitals. The first excitation singlet or the second excitation singlet is unstable, and when the electrons return from the first excited singlet to the ground state, the energy will be released in the form of light, resulting in fluorescence.

Characteristics of glow-in-the-dark

Luminous powder first absorbs all kinds of light and heat, converts it into light energy storage, and then automatically emits light in the dark, by absorbing all kinds of visible light.

It can be reused an unlimited number of times, especially for short-wave visible sunlight and ultraviolet rays below 450 nm.

Light UV light has a strong absorption capacity.

Photoluminous energy storage luminous powder is a phosphor that stores light energy after being irradiated by natural light, sunlight light, ultraviolet light, etc., and then slowly releases it in a fluorescent way after stopping light irradiation, when a certain normal temperature substance passes a certain wavelength of incident light is usually ultraviolet or X-ray.

Irradiation, absorption of light energy into the excited state, and immediately de-excitation and emitting an outgoing light longer than the wavelength of the incident light, usually in the visible band.

When light hits certain atoms, the energy of the light causes some electrons around the nucleus to jump from the original orbital to the higher energy orbital, that is, from the ground state to the first excited singlet state or the second excited singlet state. The first excited singlet state or the second excited singlet state etc is unstable, so it will return to the ground state, and when the electron returns to the ground state from the first excited singlet state, the energy will be released in the form of light, so noctilucent light is produced.

Parameter. (1) Excitation spectrum: the relationship between the intensity or luminous efficiency of a certain emission spectrum line and the spectral band of the luminescent material and the wavelength of the excitation light under the excitation of different wavelengths of light.

2) Emission spectrum: the intensity of luminous materials of different wavelengths under the excitation of a certain excitation light.

3) Fluorescence intensity: The fluorescence intensity is related to the fluorescence quantum yield, extinction coefficient and content of the substance.

The principle of luminous coating (luminescent material) is that the electrons are exposed to daylight during the day, and the electrons transition to a higher energy level and absorb energy; At night, electrons jump from a high energy level to a low energy level, emitting light and no radiation.

Phosphors are usually divided into two categories: photoinduced energy storage luminous powder and radioactive luminous powder.

1. Photoluminous powder for energy storage.

After being irradiated by natural light, daylight light, ultraviolet light, etc., phosphor stores the light energy, and after stopping the light irradiation, it is slowly released in a fluorescent way, so it can still see the light at night or in the dark, and the duration is as long as a few hours to more than ten hours.

2. Luminous powder with radioactivity.

It is to incorporate radioactive substances into phosphors, and use the rays emitted by radioactive substances to excite phosphors to emit luminescence, which has a long luminous light emitting time, but has a small range of applications such as toxic and harmful and environmental pollution.

Popular science of fluorescent brighteners:

It is a class of fluorescent dyes that belongs to a separate category in the colour index (abbreviation). The molecular structure of the fluorescent brightener is mainly composed of a continuous conjugated system containing aromatic rings and one or more substituents, and the special chemical structure allows it to absorb the invisible ultraviolet rays in the light, and then excite the fluorescence visible to the naked eye (usually blue or blue-violet);

This fluorescence can make up for the lack of blue light in the reflected light of white objects with yellowish tint, so that the reflected light in the blue band is enhanced, so that the whiteness and brightness of white objects can be seen by the naked eye, and the vividness of colored objects is brighter and more pleasant.

This characteristic of fluorescent brighteners has led to its rapid development in textiles, paper, detergents, plastics and other fields, and is considered one of the three major achievements in the dye industry in the late 20th century.

At present, there are more than 15 types of fluorescent brighteners produced worldwide, and more than 1,000 types of fluorescent brighteners are commercialized. According to the different structures, fluorescent brighteners can be divided into stilbene type, benzoxazole type, pyrazoliline type, coumarin type, naphthalimide type, and other types. Among them, stilbene fluorescent brightener is the most rapidly developing branch.

The above content referenceEncyclopedia - phosphor.

People's Daily Online-Fluorescent brightener, do you really understand.

Luminescence is caused by phosphors.

Phosphors (commonly known as luminous powders) are usually divided into two categories: photoinduced energy storage luminous powder and radioactive luminous powder.

1. Photoluminous powder is a phosphor that stores light energy after being irradiated by natural light, daylight light, ultraviolet light, etc., and then slowly releases it in a fluorescent way after stopping light irradiation, so it can still be seen at night or in a dark place, and the duration is as long as a few hours to more than ten hours.

2. Luminous powder with radioactivity is mixed with radioactive substances in phosphors, and the rays emitted by radioactive substances are used to stimulate phosphors to emit light, which has a long luminous light time, but is toxic and harmful and environmentally polluted.