Maximum spread

In a subsequent study, Chandra and Avedisian13851 investigated droplet impingement on a ceramic porous surface. It was found that the spreading rate of a droplet on the porous surface at 22 °C is lower than that on the stainless steel surface, and for a given temperature the maximum spread diameter is smaller on the ceramic surface... 

Recently, Pasandideh-Fard et al.13661 developed a simple analytical model to predict the maximum spread factor on a flat solid... 

The first principal component explains the maximum amount of variation possible in the data set in one direction. Stated another way. it is the direction that describes the maximum spread of data points. Furthermore, the percent of the total variation in the data set described b) any principal component can be precisely calculated. 

The variance of the instrumental spreading function, i.e. the spreading factor of monodispersed polymer in a SEC column was determined experimentally with narrow MWD polystyrene standard samples by the method of simultaneous calibration. The dependence of the spreading factor on the retention volume deduced from a simple theoretical approach may be expressed by a formula with four physically meaningful and experimentally determinable parameters. The formula fits the experimental data quite well and the conditions for the appearance of a maximum spreading factor are explicable. 

Eg. 9 predicts that a maximum spreading factor exists at a certain particular retention volume. Differ-... 

Again, if we take the same sensititvities as in Table I, the maximum spreading of the pulse is negligible for Axo 10-3 m, namely, 10 33Axo. One needs only to consider the possible stochastic quantum gravitational effect on the refractive index. However, as the quadratic dependence is not favored theoretically, we will not pursue it further. 

Selection of test items so that they are as dissimilar a possible to each other is accomplished by choosing items which are projected far from each other and on the periphery of the plot. Such designs are useful for answering the question of whether or not the properties have an influence. A maximum spread design wa used to determine whether modification of the solvent would increase the endo/exo stereoselectivity in the reduction of an enamine from camphor. The answer was negative [17 a],... 

Selections which afford a maximum spread also provide a good initial screening design for totally new reactions. Poor candidates can be eliminated early and the study can be continued with more promising candidates, see Sect. 4.6.2. 

Although they used droplets with diameters of 2 mm and more, the work of Park et alP is interesting on account of the fact that they used four different substrates and four different hquids. They observed the impact of droplets of distilled water, n-Octane, n-Tetradecane or n-Hexadecane onto glass slides, sihcon wafers, HMDS (Hexamethyl dishazane) coated sihcon wafers or Teflon, for Reynolds numbers from 180 to 5513 and Weber numbers from 0.2 to 176. A model was constructed to predict the maximum spreading ratio, which is the ratio of the maximum spreading diameter to the initial droplet s diameter, for low impact velocities. 

The impacting process for high surface energy substrates has two stages. First, the droplet spreads to the maximum spreading... 

Becher and Becher (2) measured the spreading pressure, tt, of a series of surfactants on plant and synthetic surfaces. The surfactants were characterized by HLB (hydrophile-lipophile balance) values (3) similar to those of Jansen s adjuvants. The relationship between the spreading pressure and the contact angle can be expressed as tt = yL cos 0, where yL is the surface tension of the liquid and 6 is the contact angle between the liquid and a solid surface. Becher and Becher demonstrated that surfactants in their series which exhibited maximum spreading pres-... 

Only a few estimates have been made of the forest fire spread from nuclear detonations. Hill (1961) quotes from earlier US Forest Service studies (not available to the author) minimum forest fire areas of 500, 1000, and 2100 km for 1, 3 and 10 Mt, respectively. These areas correspond to fire occurrence at all points where the radiant heat pulse from nuclear detonations exceeds 15 cal/cm Maximum spread areas which are listed by Hill (1961) are at least a factor of ten higher. 

Selections which afford a maximum spread in the principal properties. 

A selection based on this principle will answer the question "Do the properties of the solvent have any influence at all " The selected test solvents should have a maximum spread in all their properties. Such a selection is accomplished by chosing... 

The reaction showed promising stereoselectivity when it was run without any solvent. As the reaction might involve charged species, it was quite natural to examine whether or not the selectivity could be increased in the presence of a solvent. The solvents used to investigate this were selected according to a "maximum spread" design in their principal properties, see Fig. 16.2. 

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