Radiation does not require through the material to pass, every day to see the sun is the most obvious example, although is a vacuum between the earth and the sun, nothing, but it still can feel the light and heat of the sun, also is to rely on the solar radiation on the earth, talent here growth.

So, what about radiation? General radiation refers to electromagnetic waves released from the object, such as a hotline (infrared), ultraviolet visible light waves, etc.. Later, further found that the original X light, Gama ray is also a kind of electromagnetic waves. Because he has a shorter wavelength, more penetrating ability and the ability of charged molecules, so in particular is called "ionizing radiation" therefore, radiation belong to is not equal to the wavelength of the electromagnetic wave, the sequence can be divided into radio, microwave, infrared, visible light, ultraviolet rays, X rays, and gamma rays.

Also ray emitted from radioactive material, custom radiation, more important have o (alpha beta (beta) gamma (gamma) three. Among them, the gamma ray has the most penetrating power, which is harmful to the human body, which needs to be shielded to protect the human body.

Below, we can see the nature of the visible light, infrared rays, X rays, and Gama rays.

Visible light

Around, there are red, yellow and blue ink, and so on, you can see all kinds of colorful objects. Why these objects will show different colors, is how to feel the color is not very simple but that already know that light is electromagnetic wave a, eyes can see the light, is called visible light wavelength range in 4000-8000A angstroms) about. The sun is light and incandescent light white, contains the entire range of visible light, the red light shows. If a bunch of white light of the glass prism, separated the color of the rainbow "said it spectrum, from red, orange, yellow, green, blue, indigo and purple in sequence and the wavelength is sequentially becomes shorter.

Also has been known to have wavelength infrared red longer than, also called the hotline, although the human eye can't see but with a thermometer can amount to the addition and wavelength than shorter violet ultraviolet light, with the function of sterilization, disinfection and photosensitive film, such as infrared, ultraviolet, the naked eye cannot see light, called "invisible light"

Predictably, because the wavelength of the light is different, its nature and function also each are not identical, so, what is the wavelength. Look at the water shake to explain.

Let me observe something floating on the surface of the water, when the water wave reached, will fluctuate up and down movement. Because wave vibration and the shake to advance around transmission, direction of the vibration and direction into vertical waves called "wave" for example, light wave and electromagnetic wave one. The peak is usually convex, called the crest, and the concave bottom, called trough. Refers to the wavelength between two adjacent peak or trough distance.

Note: wavelength to "Egypt" as a unit, one equal to 1/100000000 cm.

Two, infrared

A wavelength range of 0.8100 microns, slightly longer than the red light electromagnetic wave, called infrared. Because of the heat, it is called a hot line. Although, people's eyes can not see, but I can feel the heat. Scientists can use the instrument to launch and measure infrared. For example, different temperature from the satellite measured on the earth's surface, in the exploration of underground water resources or flow etc.. Night, also can use the ground character and background of the temperature difference, engaged in night photography or observation activities. The infrared tracker mounted on missile head, used to track aircraft or warship targets. Medicine, used to measure the distribution of the body surface temperature, to understand the situation of the circulation of the blood, or use the hotline to treatment. Because infrared easily penetrate clouds, so in the meteorological satellite can also use infrared, and visible light, infrared camera photo shoot photos can understand cloud thickness and property, provide weather forecast as a reference. Other studies, applications can also use infrared to analyze the structure types and quantitative molecular widely.

Note: one micron is equal to one in a million, or ten thousand times as much as the "Egyptian".

Three, X- light (X ray)

German physicist roentgen in 1895 ad study compared with the neon lights higher layers of vacuum discharge experiments, accidentally found many phenomenon, some light will put the photographic film, and that is coated with the light emitting phosphor screen, can also through wood, rubber and even human body. Reaching out to the screen, the shadow of his hand on the screen. That he did not know what the reason is, therefore to mathematical homely to x stands for an unknown number to call this magical light, X-rays and at the society published. Since it was published, the X-ray light caused the concern of many scholars, medicine widely used in industry, now pathologic diagnosis and treatment is also affected by the great grace and roentgen as a result of this discovery in the world the glory of the first Nobel Prize in physics.

Four, Gama ray

British physicist Rutherford at Canada's university teaching, for Madame Curie radiation found very interested in, with a small container filled with radioactive radium "between the powerful magnets, the observation of the results of the photographic film, know that radium emits three different radiation. I was already aware of charged particle movement will be affected by the magnet effect, know the effect of law, so the Rutherford that bends to the right with positively charged, curving to the left with a negatively charged, and straight to the to the uncharged, with Greek letters, alpha, beta, and gamma to say it later, after careful research to know gamma ray and X-ray light with a kind of electromagnetic waves, but a shorter wavelength and block the penetration is much more than the X-ray intensity, most difficult to penetrate the lead is also quite thickness of talent. Gamma ray is released from radioactive elements, the main radiation, although the harm to the human body, but in medicine, agriculture, industry and trade in all aspects of a very wide application.

See the radiation can be divided into particle radiation and electromagnetic radiation.

Particle radiation is in fact a high-speed movement of the particle flow, such as neutrons, electrons or other particles.

Electromagnetic radiation, visible light, radio waves, X rays, and gamma rays all belong to electromagnetic radiation.

The following is a list of common radiation in a nuclear power plant

Alpha: high-speed movement of the helium nuclei (including two protons two neutrons) penetration is poor, a piece of paper can be the basic isolation, air can only move a few centimeters distance, cannot penetrate human skin.

Beta: high-speed movement of the electrons, their ability to penetrate the slightly stronger than alpha rays, use a piece of plywood can be the basic isolation, can penetrate body tissues of 1cm around. Due to its bombardment of heavy atoms (such as lead time will occur are more difficult to isolate the gamma ray, so the general use of rubber or plywood is isolated.

Neutron ray: high degree of movement of neutrons, penetrating power is also very strong, isolate it... I still remember the original said: isolation of commonly used water moderator.

Gamma rays: with high energy electromagnetic wave, basically not completely isolated, general with heavy atom substances (lead) isolation.