When exposed to the ultraviolet rays of sunlight, many explosive compounds containing nitrogen groups rapidly decompose, affecting their stability.

When describing graviton interactions, the classical theory ( i. e., the tree diagrams ) and semiclassical corrections ( one-loop diagrams ) behave normally, but Feynman diagrams with two ( or more ) loops lead to ultraviolet divergences ; that is, infinite results that cannot be removed because the quantized general relativity is not renormalizable, unlike quantum electrodynamics.

When exposed to ultraviolet light, natural ergosterols in mushrooms produce vitamin D < sub > 2 </ sub >, a process now exploited for the functional food retail market.

When a star has lost enough material, its temperature increases and the ultraviolet radiation it emits can ionize the surrounding nebula that it has thrown off.

When ultraviolet radiation is not absorbed by the atmosphere or other protective coating, it can cause damage to the skin known as sunburn or trigger an adaptive change in human skin pigmentation.

When the exposed surface reaches a temperature of about 30, 000 K, there are enough ultraviolet photons being emitted to ionize the ejected atmosphere, making it glow.

When these are used on fluorescent paper, the inked areas fluoresce less than the surrounding paper area when under an ultraviolet lamp.

When the skin is exposed to ultraviolet light after lime juice contact, a reaction known as phytophotodermatitis can occur, which can cause darkening of the skin, swelling or blistering.

When selecting for mates, ultraviolet plumage and skin coloration show a high level of selection.

When treated against ultraviolet light, these tarpaulins can last for years exposed to the elements, but non-UV treated material will quickly become brittle and lose strength and water resistance if exposed to sunlight.

When used in this context, the traditional terms " infrared " and " ultraviolet " are not literal references to specific regions of the spectrum.

When the body appears white, it is emitting a substantial fraction of its energy as ultraviolet radiation.

When a mercury vapor lamp is first turned on, it will produce a dark blue glow because only a small amount of the mercury is ionized and the gas pressure in the arc tube is very low, so much of the light is produced in the ultraviolet mercury bands.

" When the titanium dioxide absorbs ultraviolet light, it becomes powerfully reactive, breaking down pollutants that come in contact with the concrete.

When in contact with the skin, the Key lime can sometimes cause phytophotodermatitis, in which a chemical reaction makes the skin extra sensitive to ultraviolet light.

When the electron falls back to its original state, it emits a photon, resulting in visible light or ultraviolet radiation depending on the fill materials.

When held against the sun it will appear like ordinary amber, and under ultraviolet light it will glow a bright milky-blue.

When the beads are not exposed to ultraviolet rays, they are colourless and either translucent or opaque.

Another author explains, " When Saint Jerome translated the Old Testament into Latin, he thought no one but Christ should glow with rays of light — so he advanced the secondary translation.

It is also possible to produce polarised light rays using a combination of reflection and refraction: When a refracted ray and the reflected ray form a right angle, the reflected ray has the property of " plane polarization ".

When a ray hits a surface, it could generate up to three new types of rays: reflection, refraction, and shadow.

When these gamma rays collide with atoms in the mid-stratosphere, the gamma rays knock out electrons.

When cosmic rays enter the Earth's atmosphere they collide with molecules, mainly oxygen and nitrogen.

When such stars transition to supernovas, they may emit intense beams of gamma rays, and if Earth were to lie in the beam zone, devastating effects may occur.

When light rays pass from hotter to cooler, they bend toward the direction of the gradient.

When materials are exposed to short-wavelength X-rays or to gamma rays, ionization of their component atoms may take place.

When cosmic rays interact with the atmosphere, atomic interactions occur which cause a shower of lower energy particles to descend deeper into the atmosphere and to ground level.

When cosmic rays enter the atmosphere, they undergo various transformations, including the production of neutrons.

When Becquerel discovered that, with no external source of energy, the uranium generated rays which could blacken the photographic plate, radioactivity was discovered.

When he was in his prime, before his limbs lost their virility, anyone who cared to look at him closely would surely have likened his head to the sun in its glory, so radiant was it, and his hair to the rays of the sun, while in the rest of his body he would have seen the purest and most translucent crystal.

When initiated, two beams of " potential-wall energy " extend from the WBD as rays ( in the mathematical sense ) until reaching the perimeter of the current room.

When the bead is displaced from the beam center ( right image ), the larger momentum change of the more intense rays cause a net force to be applied back toward the center of the laser.

After he explained this to the Society, he proceeded: " When I understood this, I left off my aforesaid glass works ; for I saw, that the perfection of telescopes was hitherto limited, not so much for want of glasses truly figured according to the prescriptions of Optics Authors ( which all men have hitherto imagined ), as because that light itself is a heterogeneous mixture of differently refrangible rays.

When an electron and a positron collide to annihilate and create gamma rays, energy is given off.

When a larger angle of view is required, the standard method of projecting rays onto a flat picture plane becomes impractical.

When the incoming rays strike the mirror at an angle, individual rays are not reflected to the same point.

When its rays hit the user, it could create the device desired by the user and also modify the genetic structure of the body gifting it with super powers.

It is also possible to produce polarized light rays using a combination of reflection and refraction: When a refracted ray and the reflected ray form a right angle, the reflected ray has the property of " plane polarization ".

When exposed to cosmic rays ( charged particles in space that come from the stars, including our sun ), chemical elements in soils and rocks emit uniquely identifiable signatures of energy in the form of gamma rays.

When this angle is exceeded, photons no longer penetrate the semiconductor but are instead reflected both internally inside the semiconductor crystal and externally off the surface of the crystal as if it were a mirror.

When the fleet fired cannonballs, the explosives failed to penetrate Fort Sullivan's unfinished, yet thick palmetto log walls.

When laying siege, they planned and oversaw efforts to penetrate castle defences.

When used to treat patients, radiation oncologists find that they penetrate to a useful depth of about 4 – 6 cm.

When combined with cinder and earth, they provided a tough floor surface —" so tough, indeed, that 400 years later archaeologists had to take a pick axe to it to penetrate it ".

When these divisions were sent to Korea at the end of June 1950, they soon found that the 75mm gun on the M24 could not penetrate the armor of North Korean T-34 tanks, which had no difficulty penetrating the M24's thin armor.

:" When the conquest of the West ( by the Arabs ) was completed, and merchants began to penetrate into the interior, they saw no nation of the Blacks so mighty as Ghánah, the dominions of which extended westward as far as the Ocean.

When using a nebulizer for inhalation therapy with medication to be administered directly to the lungs, it is important to note that inhaled aerosol droplets can only penetrate into the narrow branches of the lower airways if they have a small diameter of 1 – 5 micrometers.

When a coleoptile reaches the surface, it stops growing and the flag leaves penetrate its top, continuing to grow along.

When electrons of the beam impact the surface of a solid, some of them may be reflected ( as " backscattered " electrons ), and others penetrate under the surface, where they collide with the particles of the solid.

When the test starts, the weight of the cone will cause it to penetrate into the grease.

When glass is used as the curtain wall, a great advantage is that natural light can penetrate deeper within the building.

When a capacitated sperm reaches the ovum, it is able to penetrate this layer with the assistance of hyaluronidase enzymes present on the surface of the sperm.

When struck by a shell or torpedo, the belt armour is designed to prevent penetration, by either being too thick for the warhead to penetrate, or sloped to a degree that would deflect the shell or torpedo.

When the combination of height contours and heat signatures indicative of a target are detected, the Skeet detonates, firing an explosively formed penetrator ( EFP ), a kinetic energy penetrator, down into the target at high speed, sufficient to penetrate armor plating and destroy what is protected by it.

When the Cylons attack, they use those backdoors to penetrate software security firewalls, disabling entire fighter squadrons outright and sabotaging vital capital-ship systems.

When combined with the strong air blast required to penetrate the large ore and charcoal stack, this may cause part of the iron to melt and become saturated with carbon in the process, producing unforgeable pig iron which requires oxidation to be reduced into cast iron, steel, and iron.

When Nogi finally called off his attempt to penetrate the Wantai Ravine on 24 August 1904, he had only 174 Meter Hill and the West and East Pan-lung to show for his loss of more than 16, 000 men.

When water is forced into one pipe, equal water is simultaneously forced out the other pipe, yet no water can penetrate the rubber diaphragm.

When she stands, she tells them of God: an evil-faced spider who tried to penetrate her.

When it encountered German armored reconnaissance units, the M8 could easily penetrate their armor with its 37 mm gun.

When the microscopic spores of the fungus come into contact with the body of an insect host, they germinate, penetrate the cuticle, and grow inside, killing the insect within a matter of days.

When the conquistadores, led by Juan de Salcedo, decided to penetrate the area, they proceeded eastward and saw for themselves the big logs along the Abra River and the big stones which were placed there to block all roads leading to the community.

When slid to the open position, beta particles are allowed to directly penetrate the ionization chamber.