Crater formation

Eraterbildung,/. crater formation pitting. Eratte. /. crate... 

Cratering Effect Tests, These tests are based on employment of the expl under actual operating conditions. Crater formation is illustrated in the following Fig ... 

C is the charge, and the ratio of surface diam of the crater to the cfepth of burial (FE/L) determines the nature of the crater. This ratio is 2 for a common crater, which is said to be 2-lined. A proper chge is one which produces a 2-lined crater a 3 lined crater represents an overcharge lower than 2, an undercharge. Based on experience, crater formation can be predicted ly the formula... 

We conclude that the microscopic etch mechanism must be the same for single crystals and sputter deposited, polycrystalline ZnO Al. For the latter, the tendency for crater formation is masked by inhomogeneous chemical or physical properties like porosity, composition or, in case of dynamic deposition, multilayered ZnO Al films. This multilayer structure results from the fact that structural properties of ZnO Al deposited by a sputter process varies depending on the position of the film relative to the race track of the sputter target [131,132]. This dependence is important for the etch rate of in-line sputter deposited films [133]. 

If the sputter deposited ZnO Al film favors crater formation upon etching, the strong hexagonal symmetry of etched craters in single crystals is... 

The amount of pigment utilized depends on the color and the hiding power required of the coating. The flow additive often is introduced to relieve surface tension variations between the coating and substrate, to eliminate pinholes or crater formation. Solvents are added as necessary to achieve flow under application conditions. 

When an explosive is set off on, in, or near the ground, it makes a hole. We call such an explosively formed hole a crater. To describe the mechanisms that take place during crater formation, we first must divide the precrater conditions into two major categories above-ground explosions and below-ground explosions. We make this distinction because the mechanisms are different in these two categories. 

Although impacts continue, and thus new crater formation is a continuous event, the crater at the 1953 impact site is the first new crater to be observed. 

We find many craters on the surfaces of icy satellites as well as on the moon. This geological structure is a quite general feature found on the solid bodies, which means tliat high-velocity impacts happen frequently in the solar system. Therefore, many experiments Irave been conducted to investigate crater formation in sand and rocky materials, especially those related to lunar geology [16]. Since many icy solid bodies have been discovered in the outer solar system. 

U. Voids near the surface tend to result in bubble and/or crater formation. Coalescence of several craters may lead to larger cavities. This explains the loss of gloss and the surface roughness observed on heavily blushed specimens. 

Laser ablation can be used to volatilize samples. An intense laser pulse is focused onto a solid at sufficient pulse power and energy (e.g., millijoule energy in a pulse of 10 nanosecond, or less, duration) to remove material from the surface. Typical conditions result in crater formation after one or a few laser pulses. If performed in flowing argon at atmospheric pressure, the ablated material can be fed into an ICP for ionization. Ions may also be formed by an ablation pulse in a vacuum and directly focused and extracted into a mass analyzer. Laser ablation/ionization is used primarily for analysis of solid compounds and materials. Virtually the entire periodic table can be analyzed with this method. 

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