27.08.2015
Since many insects can see light in the UV part of the spectrum, flowering plants have evolved patterns to attract pollinators that cannot be seen by human eyes.
UV, or ultraviolet, light is an invisible form of electromagnetic radiation that has a shorter wavelength than the light humans can see. The term “ultraviolet” means “beyond violet.” In the visible part of the spectrum, wavelength decreases — and the energy of the electromagnetic waves increases — from red through orange, yellow, green, blue and violet, so UV light has a shorter wavelength, and more energy, than violet light.
The Sun produces ultraviolet light of all categories; however, the shorter, higher energy wavelengths are absorbed by oxygen in the atmosphere, and, in particular, by the ozone layer.
Ultraviolet light, specifically UV-B, is required to allow the skin to manufacture vitamin D.
There are other benefits associated with ultraviolet light may that seem to be independent of vitamin D production.
Many potentially harmful microorganisms are quickly killed or inactivated by exposure to UV light. The effects of UV light on viruses, bacteria, and parasites have led to its use in disinfecting drinking water supplies. Some substances, when exposed to UV light, emit light at visible wavelengths, a phenomenon known as fluorescence. Biologists and zoologists are quite fond of ultraviolet light as it helps them take nighttime organism surveys in the field. Many textiles used in clothing also fluoresce, and the “black lights” often used in nightclubs and at parties exploit this fact by causing clothing to glow in the dark. Many insects can see ultraviolet light and are attracted to it, so the light is often used in insect traps.
Mapping the Milky Way and other galaxies in ultraviolet light allows astronomers to build up a picture of how galaxies evolve over time. Analyzing minerals — fluorescence under ultraviolet light can distinguish between minerals that look the same under visible light.
Microscopy — the shorter wavelength of ultraviolet light can resolve details too small to be seen with an ordinary light microscope. Chemical markers — substances that fluoresce in UV light, such as green fluorescent protein (GFP) may be used to study biological processes. Photochemotherapy — this is used as a treatment for psoriasis and some other skin conditions.
Very fine resolution photolithography — this is used in the manufacture of semiconductor components in the electronics industry. Checking electrical insulation — “corona discharge,” where damaged insulation on electrical equipment results in ionization of the air, can be detected by the emission of ultraviolet light.
Curing of adhesives and coatings — some substances polymerize and harden on exposure to ultraviolet light. UV light is classified as light because all constituents of the elctromagnetic spectrum, which UV light is one of, are light.


Can UV bulbs be an energy source used for recharging solar powered lights same as the sun, or self producing energy by using UV bulbs for the source of the energy? Scientists have finally unravelled why scorpions glow bright green under ultraviolet light.
The views expressed in the contents above are those of our users and do not necessarily reflect the views of MailOnline. It carries more energy than visible light and can sometimes break bonds between atoms and molecules, altering the chemistry of materials exposed to it. Wavelengths are measured in nanometers (nm), or billionths of a meter, and ultraviolet wavelengths range between 10nm and 400nm.
As a result, the ultraviolet that reaches the surface consists mostly of UV-A, with a little U-VB.
It converts a chemical found in the skin to a precursor of the vitamin, which then forms the vitamin itself.
Airborne virus infections, such as influenza, are generally spread via droplets expelled by coughs and sneezes.
The more energetic UV-B is responsible for sunburn, can cause premature aging of skin and can alter DNA in a way that can lead to skin cancers, such as melanoma. It has the advantages of requiring little maintenance, not affecting the taste of treated water, and leaving no potentially harmful chemicals behind.
Common fluorescent lamps, for example, are powered by UV light produced by ionizing low-pressure mercury vapor. Sensitive documents, such as currency, driver's licenses, credit cards, and passports, have invisible symbols on them that light up only in the presence of UV light. Certain birds, reptiles, and invertebrates, such as insects, fluoresce under UV, and quickly flashing a light over a small area can allow observers to count the approximate number of organisms of a given type. These lights primarily produce light in the UV portion of the spectrum, but they also produce a slight violet glow. These may be used by entomologists to study the insect population in a specific habitat or to trap and kill nuisance insects in restaurants food stores.
Visible light is simply the segment on the electromagnetic spectrum that represents light with a wavelength perceptible to the human eye. Visible light is simply the segment on the spectrum that classifies the light that the human eye can perceive. The ability is widely known - but biologists have puzzled over why the creatures might have evolved it.
Some of you are just ordering professional made PCBs, that is not always worth of cost, other are using easier way – Laser printer toner transfer technique which is not very accurate, third option is more advanced – ultraviolet light exposure of photo-resist coated PCB through film mask. UV light can also cause some substances to emit visible light, a phenomenon known as fluorescence.
This vitamin is essential to human health, and a lack of it has been implicated in immune system disorders, cardiovascular disease, high blood pressure and various cancers.


Virus particles in these droplets do not survive long if exposed to sunlight, and as a result, these diseases may not spread so easily in sunny conditions. The main disadvantage is that, unlike some chemical methods — such as chlorination — it will not protect against contamination after treatment. This light is absorbed by a special fluorescent coating, which in turn produces visible light. This is very helpful because many of these animals are mainly nocturnal and rarely if ever seen during the day.
Special posters or other works of art can also be created with the express purpose of fluorescing a certain way under a black light. They also produce a higher proportion of their ultraviolet light at the extreme end of the spectrum. Biologist Douglas Gaffin of the University of Oklahoma investigated the 'fluorescence' and found that the creatures can 'sense' light using their tails.The creatures may to have evolved the ability to help them scuttle away under rocks.
This form of light — which is present in sunlight — can be beneficial to health, as it stimulates the production of vitamin D and can kill harmful microorganisms, but excessive exposure can cause sunburn and increase the risk of skin cancer.
There is evidence that people with outdoor occupations are less susceptible to the disease. UV light stimulates the production of the pigment melanin, and because of this, people may intentionally expose themselves to strong sunlight to obtain a tanned skin. Areas where new stars are forming therefore glow more brightly in UV, enabling astronomers to identify and map these areas.
Since DTT affects the protein bonds, we thought it would cause faster damage to the C.
Lack of sunlight is the main cause of vitamin D deficiency, and sunscreen prevents its formation.
Children who spend a lot of time on outdoor activities also appear to be at less risk of developing skin cancers later in life. The effects associated with this form of light may be aggravated by the popularity of tanning studios and sunbeds, which use artificially produced ultraviolet light to cause tanning. Other possible beneficial effects include reduced incidence of cardiovascular disease, improvement of some skin conditions, and mood enhancement. As embedded part of this project is a count down timer with LCD built on AT90S2313 AVR microcontroller which can be replaced with newer ATtiny2313. Required fields are marked *CommentName * Email * Website Notify me of follow-up comments by email.



Second fix carpentry jobs adelaide
Buy second hand diamonds

Comments Uv light in aquarium

  1. mp4
    We pride ourselves not only sometimes you need something that's.
  2. ANGEL
    Sure you understand the true particles with light scattering can.
  3. Loneliness
    Believe in moving together with our customers gift wrap!) and.
  4. ISMAIL
    Stick is transparent - the ones I use are, anyway - so the light the.