waves (also known as electromagnetic radiation) is in-phase oscillation and perpendicular electric and magnetic fields in space moving in the form of waves, their propagation direction perpendicular to the plane consisting of electric and magnetic fields, the effective transmission of energy and momentum . Electromagnetic radiation can be classified according to frequency, from low frequency to high frequency, including radio waves, microwaves, infrared, visible light, ultraviolet, X-rays and gamma rays, and so on. The human eye can receive electromagnetic radiation, the wavelength of about 380-780 nanometers, known as visible light. As long as its temperature is greater than absolute zero objects, can transmit electromagnetic radiation, but the world does not exist on the absolute zero temperature is equal to or less than the object.
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About electromagnetic waves have defined the nature of the energy calculated that electromagnetic radiation electromagnetic spectrum electromagnetic radiation to reduce the harm to human therapeutic applications conduction characteristics of the application of electromagnetic waves electromagnetic spectrum of electromagnetic waves use electromagnetic waves penetration of the side effects on the human body and protectionelectromagnetic spectrum
About electromagnetic waves (Electromagnetic wave): (also known as: electromagnetic radiation, electronic smog) is a kind of energy. Defined from a scientific point of view, is the energy of an electromagnetic wave, all objects above absolute zero, will release electromagnetic waves. Just as people have been living in the air and the eye can not see the air, in addition to light, the people can not see the ubiquitous electromagnetic waves. Electromagnetic wave is such a man never met a An electromagnetic wave is generated movement patterns. Electricity and magnetism can be said on both sides, changing electric field creates a magnetic field (ie a current creates a magnetic field), changes in the magnetic field will produce electric fields. Changes in the electric and magnetic field changes constitute an inseparable unity of the field, which is the electromagnetic field, electromagnetic field that changes the spread in the space formed electromagnetic waves, electromagnetic changes on the surface of the water as the breeze generated waves in general, it is called electromagnetic waves, often referred to as waves. Nature of the electromagnetic wave frequency is low, mainly by conduction from the physical body in order to pass. The reason is the low-frequency oscillations, the magnetic interaction between the relatively slow, almost all of its energy back to the original circuit without energy radiated; high frequency electromagnetic waves that can pass free space can also be bound in the physical conductive body to pass. In free space because of the high pass frequency oscillations, the magnetic interaction becomes very fast, not all return to the original energy oscillation circuit, so electricity, magnetic energy with the electric and magnetic fields of the cycle space in the form of electromagnetic waves Spread the word, no medium can pass out of energy, which is a type of radiation. For example, the distance between the Sun and the Earth is very far away, but in the outdoors, we can still feel the warm sun light and heat, which is like Electromagnetic wave is transverse. Electromagnetic field, electric field and its direction of travel of the three mutually perpendicular. Amplitude along the propagation direction perpendicular to the direction of change for the cycle of sexual intercourse, its strength is inversely proportional to the square of the distance the wave itself is driven by energy, the energy of any position of power and amplitude proportional to the square. Its speed is equal to the speed of light c (3 × 10 eight meters per second). Propagation of electromagnetic waves in space, from the nearest electric (magnetic) strength in the same direction, the largest of its value the distance between two points is the wavelength of electromagnetic wave λ, the number of changes per second is the electromagnetic frequency f. By the relationship between the formula c = λf. Propagation of electromagnetic waves does not require media, electromagnetic waves with frequencies in the different media at different speeds. Different frequencies of electromagnetic waves, propagating in the same medium, the greater the frequency the greater the refractive index,[url=http://www.uggclearanceuks.com/][b]title=UGG Boots[/b][/url], speed is smaller. And only in the same kinds of electromagnetic waves in homogeneous media can be transmitted along a straight line if the same kind of medium is not uniform, electromagnetic wave in which the refractive index is not the same, in such a medium is spread along the curve. Through different media, it will happen refraction, reflection, diffraction, scattering and absorption, and so on. The propagation of electromagnetic wave propagation along the surface of the ground wave, and the air waves from the air and sky wave propagation. The longer the wavelength the less its decay, the longer the wavelength of electromagnetic waves around obstacles are also more likely to spread. Mechanical waves and electromagnetic waves can occur refraction, reflection, diffraction, interference, because all the waves are like sex with a wave-particle two. Refraction, reflection is the particle nature; diffraction, interference of volatility. Electromagnetic energy is the energy of the size determined by the Poynting vector, that is S = E × H, where s is the slope Indian Court vector, E is the electric field strength, H is the magneticfield strength. E, H, S perpendicular to each other constitute a right-handed relationship; that is, from S on behalf of flow per unit time per unit area perpendicular to the electromagnetic energy, in units of W / m ². Electromagnetic waves with energy, electromagnetic wave is a substance. Computing c = λf c: speed of light (which is a constant, approximately equal to 3 × 10 ^ 8m / s) unit: m / s f: frequency (unit: Hz, 1MHz = 1000kHz = 1 × 10 ^ 6Hz) λ: wavelength ( unit: m) found in 1864, British scientist Maxwell electromagnetic phenomena in the summary of previous studies based on the establishment of a complete electromagnetic theory. He concluded that the existence of electromagnetic waves, electromagnetic waves and light is derived with the same spread. 1887 German physicist Hertz experimentally confirmed the existence of electromagnetic waves. After 1898, Marconi has conducted many experiments, not only to prove Light is an electromagnetic wave, and found more in the form of electromagnetic waves, their essence are identical, but the wavelength and frequency are very different. Electromagnetic spectrum by wavelength or frequency of these waves in order to line up, is the electromagnetic spectrum. If the frequency of each band in order of priority from low to high, then they are frequency electromagnetic waves, radio waves, infrared, visible light, ultraviolet, X-ray and γ-rays. To the longest radio wavelengths, the wavelength of the shortest cosmic rays.
radio waves 3000 m to 0.3 mm. (Microwave 0.1 to 100 cm) IR 0.3 mm to 0.75 microns. (Of which: Near-infrared 0.76 to 3 microns in the infrared from 3 to 6 microns, much as 6 to 15 micron infrared, ultra-far-infrared of 15 to 300 microns) 0.7 micron to 0.4 micron visible. 0.4 micron to 10 nm UV X-ray 10 nm 0.1 nm 0.1 nm γ-ray high-energy rays is less than ~ 0.001 nm 0.001 nm Fax (TV) with a wavelength of 3-6 m; radar wavelength used short, 3 meters to a few millimeters. Generalized electromagnetic radiation electromagnetic radiation usually refers to the terms of the electromagnetic spectrum. Electromagnetic radiation is a narrow electrical equipment produced by radiation, usually refers to the infrared the following section. Electromagnetic radiation is a way to transfer energy, radiation can be divided into three categories: thermal effects of ionizing radiation has no non-thermal effects of ionizing radiation of non-ionizing radiation, electromagnetic radiation was not ionizing radiation on the human body-wave electromagnetic radiation electromagnetic radiation harmful to human injury The mechanism is the thermal effect, the cumulative effect of non-thermal effects and so on. Thermal effect: more than 70% body water, electromagnetic radiation by water molecules rubbing against each other, causing the body temperature, thus affecting other body organs to work properly. Non-thermal effects: the body's organs and tissues there is a weak electromagnetic field, they are stable and orderly, and once by external electromagnetic interference, the weak electromagnetic field in equilibrium is destroyed, the body's normal circulation conditions will be destroyed. Cumulative effect: thermal effects and non-thermal effect on the human body, has not yet had time to harm the human body to repair itself by electromagnetic radiation before, then again,[url=http://www.moncleruksales.co.uk/moncler-kid-c-10.html][b]title=Moncler UK[/b][/url], the extent of its damage accumulation occurs, a long time will become a permanent morbid or life-threatening. For long-term exposure to electromagnetic radiation of the group, even if the power is very small, very low frequencies, will induce unexpected lesions, should be vigilant! Scientists from various countries through long-term studies have shown: long-term acceptance of electromagnetic radiation can cause decreased immunity, metabolic disorders, memory loss, premature aging, heart disorders, vision loss, hearing loss, abnormal blood pressure, skin spots pox, rough, and even lead to all kinds of cancer; decreased reproductive capacity of men and women, women susceptible to menstrual disorders, miscarriage, birth defects embolism. However, without being proved, and no large-scale statistics confirm that there is no necessary link with the anti-electromagnetic radiation hazards of food are: green tea, kelp, seaweed, dress vegetables, Va, Vc, Vb1. Lecithin, blood, milk, soft-shelled turtles, crabs and other high-quality animal protein. Reduce the adverse effects of electromagnetic waves to reduce, we must cultivate the habit of self-protection. General Electric has sold the line Electrical products to detect whether radiation or electromagnetic waves, can also take a more simple way is to use home, small to receive AM (amplitude modulation) radio channels, open channels will not tune in the broadcast areas, and near to be measured TV, refrigerator, microwave oven and other appliances or computers, you will find the radio the outgoing> noise abruptly, out some distance, will restore the original small amount of noise; that can be measured by to. Different appliances have different ways of prevention, best used as a computer screen is not only shut off the computer screen switch from the LCD screen; answer the phone, it is best not placed in the waist or pants pocket, but should be used hand-held or placed at a distance of fifty centimeters at the human body; buy a home while away from the substation equipment and base station locations. Three Nordic 1993 study of Swedish survey released by the impact of electromagnetic radiation 2mG above, the opportunity is suffering from leukemia 2.1 times normal, suffering from brain swelling and ulcers of 1.5 times the normal chance of above information is taken from SAPIO magazines published in Japan 1996.3. (4-1), the experts recommended: measures to prevent the electromagnetic wave 10 Reasons for 1 as far away from the more distant from the electro-chemical products, the impact of electromagnetic waves by the smaller. (2) can not be far away from the use of time as short as possible when another strong electromagnetic wave, the shorter, the smaller the impact. 3 small selection of products, electromagnetic fluorescent light bulb than a small, wireless phones, mobile phones smaller than 4 and its use of large, try to use the same kinds of small home appliances, large, not only the high power consumption, electromagnetic waves are strong. 5 Young people should pay special attention to cell division, strong positive impact on vulnerable young people, pregnant women, with particular attention. 6 To know the safe distance from the manufacturers determine the number of electromagnetic waves are not allowed to go clear of the measure. 7 Note that the rear and both sides of the TV and PC released from the rear and sides of a strong electromagnetic waves. 8 plug to unplug it when not plugged in when most of the electromagnetic waves that will be released. 9 to pay special attention to sleep when sleep time is usually very long, even small amounts of exposure to its impact will be great 10 non-dependent power can not change the mentality of electro-chemical products around the life, opportunities for exposure to electromagnetic waves is greatly increased. Sound waves and water waves with similar characteristics, the nature of electromagnetic waves with a wave. Refraction phenomena can occur. Its speed, wavelength, frequency satisfy the relation between the formula: velocity = wavelength × frequency. Electromagnetic wave propagation velocity in the air as the speed of light, the wavelength λ = 300 / frequency F (GHz) mm. Geostationary satellites to Earth from the propagation time of about 1 / 8 sec. Applications for the transverse electromagnetic waves, can be used for detection, positioning, communications and so on. Electromagnetic spectrum (wavelength from long to short) is a radio wave, microwave, infrared, visible light, ultraviolet, roentgen rays (X rays), gamma-ray Application: microwave radio waves used for microwave communications, satellite communications, infrared use on the remote control, thermal imaging devices, infrared-guided missiles and other visible light is used to observe all things biological basis of UV disinfection for medical, verify counterfeit currency, measure distances, engineering testing and other X-ray gamma-ray camera is used for CT treatment, the atomic transition occurs resulting in the new rays, etc. radio waves. Radio and television are used to carry out electromagnetic waves. In radio, people to have the sound signals into electrical signals, then these signals from the high-frequency oscillations of the electromagnetic wave propagation with the surrounding space. In another place, people use the receiver receives these electromagnetic waves, the electrical signal which in turn restore the sound signal, which is the general process of radio broadcasting. In television, in addition to treatment as sound as the wireless broadcast signal, but also the image of the optical signals into electrical signals, and also these two signals together with the high-frequency oscillations of the electromagnetic wave propagation to the surrounding space, The television receiver to which these electromagnetic signals and then restore the sound signals and optical signals, thus demonstrating the TV screen and speakers in the sound. Electromagnetic field (or field) change over time, in cycles. During one oscillation cycle is called wavelength propagation distance. The reciprocal of the oscillation cycle, ie vibrations per second (change) the number of known frequency. Obviously, the product of wavelength and frequency is transmitted from the second, that velocity. That wavelength λ, frequency f, the speed of V, was: λ = V / f wavelength into the unit is meters (m), the speed in meters / second (m / sec), frequency in Hz (Hertz , Hz). The entire electromagnetic spectrum, from radio waves to cosmic rays contain a variety of waves, light, and rays of the collection. Different frequencies of radio waves named paragraph (3KHz-3000GHz), infrared, visible light, ultraviolet, X-rays, γ-rays (gamma rays) and cosmic rays. In the 19th century, Marconi and Italian troops with the Russians in 1895 Popov conducted a radio communications test. Over the next 100 years, until 3000GHz spectrum from 3KHz be recognized, developed and gradually use. Depending on the holders of broadcast properties, the use of different services, the entire radio spectrum to be divided, is divided into 9 sections: very low frequency (VLF), low frequency (LF), medium frequency (MF), high frequency (HF), very high frequency ( VHF) UHF (uHF) ultra-high frequency (sHF) extremely high frequency (EHF) and to high frequency, the corresponding band from the very (ultra) long wave, long wave, medium wave, short wave, VHF, UHF and centimeter wave, millimeter wave and Simi Bo (collectively referred to as microwave after four kinds). The table below. Classified section of the radio spectrum and band No. band name frequency range (including the upper limit free) band name of the wavelength range (including the upper limit without limit) 1 very low frequency (VLF) 3 ~ 30 kilohertz (KHz) very low frequency long-wavelength 100 ~ 10km 2 (LF) 30 ~ 300 kilohertz (KHz) 10 ~ 1km 3 long-wave frequency (MF) 300 ~ 3000 kilohertz (KHz) AM 1000 ~ 100m 4 high frequency (HF) 3 ~ 30 megahertz (MHz) 100 SW 10m 5 very high frequency (VHF) 30 ~ 300 megahertz (MHz) UHF 10 ~ 1m 6 UHF (UHF) 300 ~ 3000 megahertz (MHz) UHF microwave 100 ~ 10cm 7 ultra-high frequency (SHF) 3 to 30 gigahertz (GHz) cm wave 10 ~ 1cm 8 extremely high frequency (EHF) 30 ~ 300 gigahertz (GHz) millimeter wave frequency 10 ~ 1mm 9 to 300 to 3000 gigahertz (GHz) Simi Bo 1 to 0.1 mm electromagnetic therapeutic applications after receiving the body cells contain the same material resonance, thus enhancing microcirculation and promote metabolism, resulting in the restoration of human disease, so patients can quickly recover, patients can improve their non-resistance. For example, China Ren TDP, by a large number of clinical trials in on the basis of specific recognition can be applied to the electromagnetic spectrum of radiation treatment of cervical spondylosis, lumbar disc herniation, low back pain, lumbar strain hungry, rheumatoid arthritis, sciatica, facial palsy, wound healing, trauma, infection, frostbite, gastritis, diaphragm spasm, neurodermatitis, eczema, migraine, headache, dysmenorrhea, hemorrhoids. Been widely applied to the surgical, internal medicine, gynecology, pediatrics, neurology and other diseases. At the same time through the National Institute of Metrology precise determination of such authority, confirmed that the human body without any side effects. Conducted for the transverse electromagnetic waves. Electromagnetic field, electric field and its direction of travel of the three mutually perpendicular. Amplitude along the propagation direction perpendicular to the direction of change for the cycle of sexual intercourse, its strength is inversely proportional to the square of the distance the wave itself is driven by energy, the energy of any position of power and amplitude proportional to the square. Its speed is equal to the speed of light c (3 × 10 ^ 8 per meter). Propagation of electromagnetic waves in space, from the nearest electric (magnetic) strength in the same direction, the largest of its value the distance between two points is the wavelength of electromagnetic wave λ, the number of changes per second is the electromagnetic frequency f. By the relationship between the formula c = λf. Through different media, it will happen refraction, reflection, diffraction, scattering and absorption, and so on. The propagation of electromagnetic wave propagation along the surface of the ground wave, and the air waves from the air and sky wave propagation. The longer the wavelength the less its decay, the longer the wavelength of electromagnetic waves around obstacles are also more likely to spread. The application of electromagnetic waves. For the transverse electromagnetic waves, can be used for detection, positioning, communications and so on. Is the electromagnetic spectrum electromagnetic spectrum radio waves, microwaves, infrared, visible light, ultraviolet, roentgen rays (X rays), gamma rays, first, the radio waves used in communications, microwave for microwave, infrared for remote control, thermal imaging devices, infrared-guided missiles, visible light is used to observe all things biological basis of UV disinfection for medical, verify counterfeit currency, measure distances, engineering testing, etc., X-ray camera for CT, Gamma-ray for the treatment, so atom transition in order to generate new rays, etc. use radio and television waves are carried out using electromagnetic waves. In radio, people to have the sound signals into electrical signals, then these signals from the high-frequency oscillations of the electromagnetic wave propagation with the surrounding space. In another place, people use the receiver receives these electromagnetic waves, the electrical signal which in turn restore the sound signal, which is the general process of radio broadcasting on television, in addition to treatment as the voice of the wireless radio signals as , but also the image of the optical signals into electrical signals, and also these two signals together with the high-frequency oscillations of the electromagnetic wave propagation to the surrounding space, and the television receiver to which these electromagnetic signals will then restore the sound signals and optical signals, thus demonstrating the TV screen and speakers in the sound. The use of radio frequency electromagnetic waves is high, the scope is very large, and the use of television is even higher frequency electromagnetic waves, the range is greater. Penetration of electromagnetic waves with wave-particle duality of electromagnetic waves because the wavelength is inversely proportional relationship with the photon energy, while the shorter wavelength of the photon energy is larger, stronger penetration. Electromagnetic effects on the human body and protective one, the side effects of electromagnetic pollution on the human body (1) Electromagnetic radiation is cardiovascular disease, diabetes, cancer, mutation of the main incentives (2) electromagnetic radiation harmful to human reproductive system, nervous system and immune system cause direct harm (3) electromagnetic radiation is caused by miscarriage, infertility, birth defects and other lesions induced factor (4) excessive electromagnetic radiation directly affects the child's physical organization, bone development, resulting in vision, liver hematopoietic function, severe may lead to retinal detachment (5) of electromagnetic radiation can decrease male sexual function, female endocrine disorder. Second, the electromagnetic wave protection 1 standards and relevant provisions of the electromagnetic environment. For the control of electromagnetic waves of modern life, environmental pollution, to protect the health of people, December 22, 1989 issued by the Ministry of Health medium and short wave should be less than lOV / m, FM should be less than 5V / m, the microwave should be less than 10μW/cm2. China's relevant departments have also developed a Development of mobile communications for the Beijing Environmental Protection Bureau on February 17, 2000 issued by the country's first electromagnetic pollution, to regulate the management of the (stations) of the construction and operation, to prevent the electromagnetic pollution on the environment. This provision clearly capable of producing electromagnetic radiation of mobile communication units (stations) in the building prior to its environmental approval procedures, and to apply for approval and acceptance of environmental protection, monitoring by the environmental protection departments, local power density in line with national The frequency 20 MHz ~ 3000 MHz range, the power density exposure limit derived in 40μW/cm2 the standards in order to officially put into use, more than this standard must be disabled or rectification; building cellular mobile communication before the base station density distribution to predict the user, using the best frequency reuse method to minimize the number of base stations; residents upstairs in the construction of mobile station (station), advance units of the building or the property management unit of property must seek the views of residents living ; wireless paging communication, cluster communication antennas shall not be less than the minimum allowable height 40m, while the outdoor cellular base station antenna is generally not less than 25m, 50m transmitting antenna direction of the main shoot within 30m of non-main direction of radiation within generally not built higher than the antenna hospitals, kindergartens, schools, residential and other buildings; construction units should be installed in these types of antenna locations electromagnetic radiation warning signs. (2) electromagnetic wave protection measures. According to the characteristics of electromagnetic wave attenuation with distance, in order to reduce the harm to the residents of electromagnetic waves, electromagnetic transmitter power should be larger, may produce a strong electromagnetic wave in the workplace and facilities, such as television, radio, radar, communications stations, microwave transmission stations, as far as possible away from residential areas located in the outer suburbs or areas of high terrain. Must be set in the city, often close to residential areas and residents of facilities within the venue, such as substations, etc., should maintain a certain living range from security, to ensure that its borders in line with the requirements of environmental health standards of electromagnetic waves. Meanwhile, the need to use to shield electromagnetic radiation, reflection or absorption of electromagnetic waves of copper, aluminum, steel and other metal wire or polymer film materials for electromagnetic shielding materials, electromagnetic radiation energy will be limited to within the space provided. 3 high-pressure, especially high voltage transmission lines away from homes, schools, playgrounds and other crowded areas. Using the computer, should be used low radiation monitor, and maintain the human body and screen of not less than 75cm distance from the front, side and back of not less than 90cm, the best installation of shields. 4 should be strictly controlled the density of mobile communication base stations, set up in urban areas to ensure a variety of mobile communication base station transmitting antenna above the surrounding buildings, in kindergarten, school buildings, hospitals and other buildings shall not be established within a certain range around the transmitting antenna. 5 bedroom home in order to reduce electromagnetic pollution and its harmful effects, should always be on the room ventilation to keep indoor air flow. Scientific use of household appliances: for example, watching TV or home theater, listen to music center should be maintained over long distances, and to avoid all kinds of electrical appliances at the same time open; use a computer or video games should not be too long duration and so on. 6 using mobile phones, to minimize talk time; phone antenna as possible deviation from the top of the head, stretching as far as possible to the antenna; in the installation of mobile phone headsets. 7 In addition, you can take a certain amount per day of vitamin C or vitamin C, eat more fresh vegetables, such as pepper, bell pepper, cedar, cauliflower, spinach, etc.; eat more fresh fruits such as oranges, dates and so on. Note also eat food rich in vitamin A, C, and protein foods such as tomatoes,[url=http://www.moncler-online.de/][b]title=Moncler Online[/b][/url], lean meat, liver, bean sprouts, etc.; regularly drink green tea. These dietary measures can play a positive to some extent, prevent and mitigate damage caused by electromagnetic radiation effect on the human body. 8 electromagnetic radiation was only the last four decades, a new awareness of environmental pollution, electromagnetic radiation is now still in the awareness and research stage. Because it is invisible, intangible, difficult to detect, so easily lead to people's concerns. In addition, some reports on the electromagnetic radiation is not the objective, the lack of science, leading to unnecessary misunderstandings and panic. Generally speaking, to determine whether the living environment of electromagnetic radiation pollution, electromagnetic radiation from the main radiation direction, and distance from the radiation source, duration and other aspects into account. So, while strengthening the electromagnetic protection for electromagnetic pollution should also take a scientific attitude, objective analysis, taken seriously, must not others, and is not responsible for the blind exaggerated, causing people to understand the confusion. Of course, with the level of development of science and technology, people and the danger of electromagnetic pollution will gradually deep understanding of people, many of the answers will eventually be opened. Open Category: Natural sciences, physics, energy, physics, electromagnetics, Related articles：
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