Solar radiation protectants

TBD. Possible causes Include thermal control system malfunction, solar radiation protection inadequate, Insufficient radiator heat rejection. 

Shapiro and Robertson (59, 60) evaluated 79 dyes as solar radiation protectants for spsy moth, Lymantria dispar nucieopolyhedrovirus (Ivertical distance of 50 cm from the light bulb (intensity). Congo red was die only dye tested that fully retain LdMNPV activity after artificial solar radiation exposure. Solar protectants absorbed at 280-320 nm (UV-B), as well as 320-400 nm (UV-A) (Table 3). 

Lines or equipment which can be left full of liquid under non-flow conditions and which can be heated while completely blocked-in must have some means of relieving pressure built up by thermal expansion of the contained liquid. Solar radiation, as well as other heat sources, must be considered. Lines or equipment which are hotter than ambient when blocked in and which cannot otherwise be heated above the blocked-in temperature do not need protection against liquid thermal expansion. The following are common examples of some thermal expansion mechanisms. 

Simple models for louvers and other solar protection devices are based on a statement of constant reduction of the solar radiation flux on the window. A common assumption is that a louver is controlled so that no direct light can penetrate into the room. 

Solar radiation may fall on outside walls or roofs, raising the skin temperature, and this must he taken into account. Most cold stores are huilt within an outer envelope which protects them from the elements and from direct sunshine. In cases where the insulation itself is subject to solar radiation, an allowance of 5 K higher outside temperature should he taken. Heat load must he estimated through all surfaces including piping, ducts, fan casings, tank walls, etc., where heat flows inwards towards the cooled system. 

Notice from this equation that energy is inversely related to wavelength. This explains why you put on sunscreen to protect yourself from UV solar radiation (<400 nm) and a lead apron when dental x-rays (<10 nm) are being taken. Conversely, IR (>700 nm) and micro-wave photons (>80,000 nm) are of relatively low energy (but don t try walking on hot coals). 

Ozone (O3) is formed in the tropical stratosphere, around 12 to 30 miles above the ground, where solar radiation is intense it then migrates to the polar regions. The O3 concentration can be as high as 10 ppm in the stratosphere there, it absorbs a large part of the harmfirl ultraviolet radiation from the sun, thereby protecting life on Earth. CFCs are volatile and persist in the lower atmosphere (the troposphere) because of their inert nature they resist chemical degradation reactions. It is estimated that... 

Paints and varnishes for use on exteriors of buildings must be protected from the effects of solar radiation which accelerate their degradation (photolysis and photochemical reactions). Given that M = 500 gmol-1 emax = 15 0001 mol 1 cm"1 for Amax - 350 nm, what must be the concentration (expressed in g 1 1) of a UV additive M such that 90% of the radiation is absorbed by a coating of thickness 0.3 mm ... 

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