Dust veil

It may be of interest to outline relatively recent developments. On the basis of a comprehensive analysis of volcanic chronology since 1500 AD, Lamb (1970) had introduced a criterion, the Dust Veil Index (DVI), for relating empirically the climatic effects to the characteristics of the eruption. The DVI was expressed with three alternative formulae, claimed to be equivalent, each expression being the product of three quantities ... 

Robock a., a latitudinally dependent volcanic dust veil index and its effect on climate simulations. J. Volcano). Geothenn. Res., 11, 67-90 (1981). 

FIGURE 23.8 Trends in natural and human influences relevant to Earth s climate during the past four centuries (Lean and Rind 1996). Compared are annual averages of (a) estimates of the solar total radiation, from Figure 23.7c (b) variations in the amount of volcanic aerosols derived from an index (global dust veil index) of known eruptions and (c) the concentration of C02 in the atmosphere. The decade-averaged estimate of the Earth s surface temperature, shown in (d), combines continuous instrumental records from the most recent 150 years with a less certain reconstruction based on various climatic indicators. 

A quantitative method developed by H. H. Lamb for comparing the magnitude of volcanic eruptions. The formulae use observations either of the depletion of the solar beam, temperature lowering in middle latitudes, or the quantity of solid matter dispersed as dust. The reference dust veil index is 1000, assigned to the Krakatoa 1883 eruption, and the index is calculated using all three methods, where the information is available, for statistical comparison purposes. Abbreviated D.V.I. 

Research Series, vol. 16, pp 257-315 Robin G, de Q (1988) The Antarctic ice sheet, its history and response to sea level and climatic changes over the past 100 million years. Paleo Paleo Paleo 67 31-50 Robok A (1981) A latitudinally dependent volcanic dust veil index, and its effect on climate simulations. J Volcanol Geotherm Res 11 67-80... 

The ejected material forms a cool molecular and dusty envelope which initially veils the star from optical observations as it goes through the stages of Mira variable followed by OH-infirared star or infrared carbon star later the star becomes hot enough to ionize part or all of the expanding gas-dust envelope forming a planetary nebula. 

For each star that shines, there are a certain number that remain hidden, masked by a veil of dust. Observing the Universe in submillimetre waves, where the heated dust shines at its brightest, it has been possible to show that in the young Universe, stars were born at a rate about five times greater than was suggested by observations in the visible. 

I stop moving to the music and there is a major rush of energy that moves through the crowd and into my body. It feels like the migraine is a veil that drapes my forehead. It is lifting off, from the front of my head to the back, transforming it into sparkle dust in my mind and dissolves (psychol5dic effect). 

This is the well-known Horsehead nebula in the constellation Orion. It is made mostly of dust, plus some cold hydrogen gas, and it stands out in silhouette against a more distant mass of hot, luminous hydrogen. It is similar to the great black rift and the indistinct dark clouds which obscure great sections of the veil of stars in the Milky Way. 

She knew her cheeks would be blushing, she could feel the heat. Hopefully the smears of mud and dust would be veiling the fact. "Carmitha said something to me before she left. Something about you. It was a question. A good one."... 

Increase of efficiency dust separation is caused by installation in the device of the axial sprinkler punched by apertures of small diameter, placed on a screw line. Apertures are executed in such a manner that the jet of a liquid from them is directed tangential to a surface of an axial sprinkler. The comer of an inclination of a jet is provided with directing plugs, compaction in apertures of an axial sprinkler. Thus due to impact following under a pressure the spiral film-drop liquid veil is formed of apertures of an axial sprinkler of liquid jets with a peripheral edge of blades vortex generator. 

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