Distributed roughness

The extinction of a light beam or incident radiation associated with a cloud of particles basically involves a measure of a moment of the particle number-size distribution roughly proportional to the surface concentration. The extinction of a light beam is well-developed basis for semi-quantitative measurement of particles suspended in gases. Devices for these purposes, including smoke photometers, have been available commercially for many years. They may take many forms, one of which is the transmissome-ter, or opacity instrument. 

Within this one per cent, the elements other than hydrogen and helium may be distributed roughly in the same order of frequency as they are on earth we don t know at present. 

The pore size distribution (PSD) indicates the fraction of the space within a particle occupied by micropores, mesopores, and macropores. An adsorbent s pore size distribution roughly indicates its potential uptake capacity, may reveal possible mass transfer constraints, and can show its potential for separating molecules by a sieving effect. In fact, sometimes pore size information is gleaned from diffusion rate data for molecules of known sizes, i.e., the extent to which sieving effects are observed. 

Since Urms for irregular waves distributes roughly 0.158 < a ms/k < 0.203,... 

Vapor pressure. Individual molecules in the liquid have different amounts of kinetic energy, distributed roughly along a normal curve. Some molecules will have energy exceeding the inter-molecular forces of attraction. These molecules will vaporize. The number of molecules, per unit time and unit area, that vaporize dictates the vapor pressure of the substance. Since kinetic energy is directly proportional to temperature, vapor pressure is dependent solely on temperature. 

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