Surface damage

Substances in this category include Krypton, sodium chloride, and diamond, as examples, and it is not surprising that differences in detail as to frictional behavior do occur. The softer solids tend to obey Amontons law with /i values in the normal range of 0.5-1.0, provided they are not too near their melting points. Ionic crystals, such as sodium chloride, tend to show irreversible surface damage, in the form of cracks, owing to their brittleness, but still tend to obey Amontons law. This suggests that the area of contact is mainly determined by plastic flow rather than by elastic deformation. 

Heiland W and Taglauer E 1973 Bombardment induced surface damage in a nickel single crystal observed by ion scattering and LEED Rad. Effects. 19 1-6... 

Meir and Clifton [12] study shocked <100) LiF (high purity) with peak longitudinal stress amplitudes 0.5 GPa. A series of experiments is reported in which surface damage is gradually eliminated. They find that, while at low-impact velocities the dislocations in subgrain boundaries are immobile and do not affect the dislocation concentration in their vicinity, at high-impact velocities ( 0.1 km/s) dislocations emitted from subgrain boundaries appear to account for most of the mobile dislocations. 

Crystals Role of Surface Damage, in Shock Waves in Condensed Matter (edited by S.C. Schmidt and N.C. Holmes), Elsevier Science, Amsterdam, 1988, pp. Ill-HQ. 

Warping, residual stresses in pressing, cutting possible surface damage lowered ductility higher DBT. 

Quantum well interface roughness Carrier or doping density Electron temperature Rotational relaxation times Viscosity Relative quantity Molecular weight Polymer conformation Radiative efficiency Surface damage Excited state lifetime Impurity or defect concentration... 

To minimize surface damage, static SIMS mass spectrometers should be as efficient as possible for detecting the total yield of secondary ions from a surface. Also, to be able to separate elemental from molecular species, and molecular species from each other, the mass resolution usually given as the mass m divided by the separable mass Am, should be very high. With this in mind, two types of mass spectrometer have been used - in early work mainly quadrupole mass filters and, more recently, time-of-flight mass spectrometers. 

Cathodic protection applications in fresh water include use of ferrite-coated niobium , and the more usual platinum-coated niobium . Platinised niobium anodes have been used in seawater, underground and in deep wells " and niobium connectors have been used for joining current leads Excellent service has been reported in open-seawater, where anodic potentials of up to 120V are not deleterious, but crevice corrosion can occur at 20 to 40V due to local surface damage, impurities such as copper and iron, and under deposits or in mud ... 

The Gurley number is used to characterize membranes because the measurement is accurate and easy to make, and deviations from specified values are a good indication of problems. A higher Gurley value than specified can indicate the membrane has surface damage a lower value than specified can indicate pinholes. 

Combined action of wind and water Surface damage... 

Dermal exposure of rats to doses of dimethyltin dichloride at 80 mg/kg body weight produced dermal necrosis with the formation of black scars the same dose of dibutyltin dichloride produced little surface damage to the skin together with subcutaneous oedema. Dioctyltin dichloride produced no skin lesions (Barnes Stoner,... 

It was observed in other works that in sulfide electrolyte, decomposition of ZnSe was still obtained stable PECs could be constructed though from singlecrystal, n-type, Al-doped ZnSe electrodes and aqueous diselenide or ditelluride electrolytes [124]. Long-term experiments in these electrolytes were accompanied by little electrode weight loss, while relatively constant photocurrents and lack of surface damage were obtained, as well as competitive electrolyte oxidation. Photoluminescence and electroluminescence from the n-ZnSe Al electrodes were investigated. 

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