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Irradiance solar

The above-mentioned codes contain requirements for accelerated durabiUty tests. In addition, interlayer manufacturers and laminators expose test samples for several years under extreme weather conditions, eg, the Florida coast and Arizona desert. The laminated products weather extremely well, with no change in the plastic interlayer. Occasionally, clouding is noted around the edges when exposed to high humidity for long periods, but this is reversible. Colored areas of PVB laminates may fade while subjected to extensive uv/solar irradiation, which could cause an appearance issue. This has not, however, been shown to alter the laminate s other performance properties. [Pg.526]

Data are provided as measured data or prepared data, representing typical data for a period of several years. Design reference years (DRY) established using methods developed with the framework of the lEA (International Energy Agency) represent characteristic data for a period of 10 years, condensed into a one-year data set. Internal coherence, e.g., between solar irradiation and air temperature, is maintained. For the United States, typical meteorological year (TMY) files are based on measurements in the period 1954 through 1972. [Pg.1066]

Sonnen-. of the sun, sun, solar, helio-. -auge, n. adularia. -bahn, /. ecliptic, -belichtung, /. exposure to sunlight, solar irradiation, insolation. [Pg.414]

A 1995 reconstruction of historical solar output levels from 1600 to 2000 shows that solar irradiance has risen over time, hut with many short-term peaks and troughs in the overall curve of increase, increas-... [Pg.243]

Willson, R. C. (1997). Total Solar Irradiance Trend During Solar Cycles 21 and 22. Science 277 1963-1965. [Pg.251]

On a global scale, the atmosphere serves as the major pathway for the transport and deposition of contaminants from emission sources to terrestrial and aquatic ecosystem receptors (22, 27). Once a contaminant is airborne, the processes of atmospheric di sion, transport, transformation, and deposition act to determine its fate. These processes are complex and the degree to which they influence the fate of a particular contaminant is dependent on its physico-chemical characteristics, the properties and concentrations of coexisting substances, and the prevailing meteorological conditions, including wind, precipitation, humidity, temperature, clouds, fog, and solar irradiation. [Pg.138]

Habitat Description Solar Irradiance (PAR) Production Rate Treatment... [Pg.197]

While most climate models consider feedbacks as being dependent on temperature (usually Ts), there are many other dependent variables in the climate system that could be involved, for example solar irradiance at the ground or rainfall. However, it is customary to describe these mathematically as functions of Tg,... [Pg.445]

Texture, organic matter content, oxygen status and pH values of soil in use area(s) Amqlmts and timing of precipitation Temperature and solar irradiance in use area(s) (temperate vs. tropical vs. nordic)... [Pg.842]

The time of year in which a pesticide is applied significantly affects its dissipation rate due to temperature, moisture, and solar-irradiance effects on abiotic and biotic dissipation processes. For example, dissipation rates for agrochemical applications made in the springtime are normally greater than those observed for fall (autumn) applications. Thus, the timing of agrochemical applications made in field soil dissipation studies should closely match those occurring under acmal-use conditions. [Pg.849]

Another layering that occurs within the 1000 metre surface ocean is the distinction between seawater receiving solar irradiation (the photic zone) and the dark water below. The sun provides heat, UVR, and photosynthetically active... [Pg.16]

Another explanation to global warming is that it is a result of natural variations in solar irradiance, see e.g. Lean and Rind (2001) and Mende and Stellmacher (2000). [Pg.76]

Augugliaro V, Baiocchi C, Prevot AB, Garcia-Lopez E, Loddo V, Malato S, Marci G, Palmisano L, Pazzi M, Pramauro E (2002) Azo-dyes photocatalytic degradation in aqueous suspension of Ti02 under solar irradiation. Chemosphere 49 1223-1230... [Pg.332]

The same group, in a previous work, reported on the realization of a hybrid anode electrode [197]. An appreciable improvement in methanol oxidation activity was observed at the anode in direct methanol fuel cells containing Pt-Ru and Ti02 particles. Such an improvement was ascribed to a synergic effect of the two components (photocatalyst and metal catalyst). A similar behavior was also reported for a Pt-Ti02-based electrode [198]. Another recent study involved the electrolysis of aqueous solutions of alcohols performed on a Ti02 nanotube-based anode under solar irradiation [199]. [Pg.114]

If the primeval atmosphere did not contain enough CO2 to maintain a greenhouse climate, the much lower solar irradiation at that time would have led to frozen oceans. But that would make almost all the assumed synthetic mechanisms for the formation of biomolecules impossible Bada et al. (1994) consider external help as a way out of this dilemma. They assume that the energy from meteor impacts (diameters up to around 100 km), converted into heat, would have sufficed to melt the oceanic ice. If such a process were to have occurred periodically, chemical evolution reactions (see Chap. 4) could have taken place in the ice-free periods and have led finally to biogenesis. [Pg.39]

Global warming, mainly determined by the CO2 greenhouse effect Cooling, caused by reflection of solar irradiation due to the presence of thick clouds of sulphuric acid... [Pg.45]

Fig. 5.43 The UV part of the sun spectrum, the erythema action spectrum and the biological effective solar irradiance. The biological effective irradiance has been obtained by folding the radiation density of the sun with the erythema action spectrum. Fig. 5.43 The UV part of the sun spectrum, the erythema action spectrum and the biological effective solar irradiance. The biological effective irradiance has been obtained by folding the radiation density of the sun with the erythema action spectrum.
The low energy density of solar energy places severe economic restrictions on potential light-dependant biohydrogen processes. For example, at very favorable locations the yearly average solar irradiation could be as high as 5 kWh/m2/day which would give 6.6GJ/year. [Pg.94]

Figures 7.4(a), (b) and (c) give the spectral characteristics of three sources (a) the sun at the earth s surface, (b) a JP-4 pool fire and (c) blackbody sources at typical room fire conditions (800-1100 K). The solar irradiance is mostly contained in about 0.3-2.4 fim while fire conditions span about 1-10 pm. Figures 7.4(a), (b) and (c) give the spectral characteristics of three sources (a) the sun at the earth s surface, (b) a JP-4 pool fire and (c) blackbody sources at typical room fire conditions (800-1100 K). The solar irradiance is mostly contained in about 0.3-2.4 fim while fire conditions span about 1-10 pm.
Figures 7.5 and 7.6 give the measured spectral reflectances and transmittances of fabrics. It is clear from Figure 7.5 that color (6,white 7,black 1,yellow) has a significant effect in reflecting solar irradiance, and also we see why these colors can be discriminated in the visible spectral region of 0.6 pm. However, in the spectral range relevant to fire conditions, color has less of an effect. Also, the reflectance of dirty (5a) or wet (5b) fabrics drop to <0.1. Hence, for practical purposes in fire analyses, where no other information is available, it is reasonable to take the reflectance to be zero, or the absorptivity as equal to 1. This is allowable since only thin fabrics (Figure 7.6) show transmittance levels of 0.2 or less and decrease to near zero after 2 pm. Figures 7.5 and 7.6 give the measured spectral reflectances and transmittances of fabrics. It is clear from Figure 7.5 that color (6,white 7,black 1,yellow) has a significant effect in reflecting solar irradiance, and also we see why these colors can be discriminated in the visible spectral region of 0.6 pm. However, in the spectral range relevant to fire conditions, color has less of an effect. Also, the reflectance of dirty (5a) or wet (5b) fabrics drop to <0.1. Hence, for practical purposes in fire analyses, where no other information is available, it is reasonable to take the reflectance to be zero, or the absorptivity as equal to 1. This is allowable since only thin fabrics (Figure 7.6) show transmittance levels of 0.2 or less and decrease to near zero after 2 pm.
DNA strongly absorbs UV radiation, especially mid-range UVB (290 to 320 nm) radiation. Two major DNA lesions are induced following UV exposure, pyrimidine dimers and 6-4 pyrimidine-pyrimidone photoproducts. Because the action spectrum (induction of a biological activity as a function of wavelength) for erythema closely matches the action spectrum for pyrimidine dimer formation, DNA is believed to be the chromophore for sunburn.6 Pyrimidine dimer formation, or more properly, the failure to adequately repair dimers after solar irradiation is also the primary cause of sunlight-induced skin cancer formation.7-8... [Pg.261]


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Depth dependence, solar spectral irradiance

Irradiation solar nebula

Outdoor solar light irradiation

Solar Irradiance at the Earth

Solar irradiance curves

Solar irradiance efficiency

Solar irradiance maximum

Solar irradiance prediction

Solar irradiance reference spectra

Solar irradiance simulating

Solar irradiance tests

Solar irradiance, trend

Solar irradiation

Solar irradiation Changes

Solar irradiation sunlight

Solar irradiation/radiation

Solar spectral irradiance

Solar spectrum irradiance

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