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Crystal structure, orientation and solubility effects on friction and adhesion of various metal single crystals in vacuum
Crystal structure and orientation, and solubility effects on adhesion and sliding friction of four metal single crystals in vacuum
A crystal structure of alpha poly-p-xylylene is proposed with the help of data of oriented crystals grown during polymerization. The unit cell is monoclinic with the parameters a = 8.57 A, b = 10.62 A, c = 6.54 A (chain axis), and beta = 101.3 deg. Four repeating units per cell lead to a calculated density of 1.185 g/cu cm and a packing density of 0.71. The probable space group is P2 sub 1/m.
Crystal structure of ammonium tricyanomethide determined by X-ray diffraction
Magnesium silicate crystal structure, discussing transformations under high pressure, crystallochemistry and implications for physics of earth mantle
Mechanical properties of metals at low temperatures as function of crystal structure
Contact rule for rigid-sphere models of crystal structures
Thermionic work function of refractory intermetallic compounds and their electronic and crystal structures
Two parameter model for lattice vibrations applicable to diamond structured crystals, calculating phonon dispersion curves from dielectric screening theory
The crystal structure of d(C3T), solved at 1.4 angstroms resolution, reveals that the molecule forms a four-stranded intercalated complex. It consists of two parallel-stranded duplexes, each of which is held together by cytosine-protonated cytosine base pairs. The two duplexes are intercalated with each other and have opposite strand orientation. The molecule has a flat, lath-like appearance, and the covalently bonded cytosines have a slow right-handed twist of 17.1 degrees. However, there is considerable asymmetry. On one of the flat sides, the phosphate groups are rotated away from the center of the molecule. They are held in this orientation by bridging water molecules that bind the NH of cytosine and a phosphate group of an opposite chain. There is also considerable microheterogeneity in the structure. The cytosine hemiprotonation occurs even at pH 7 where stable crystals form.
Crystal structure influence on friction, wear, and metal-transfer characteristics of rare earth metals in vacuum
Crystal structure and lattice parameter effects on single and polycrystalline metals adhesion, friction and wear properties, discussing basal slip hexagonal metals
The crystal structure of d(C4) solved at 2.3-A resolution reveals a four-stranded molecule composed of two interdigitated or intercalated duplexes. The duplexes are held together by hemiprotonated cytosine-cytosine base pairs and are parallel stranded, but the two duplexes point in opposite directions. The molecule has a slow right-handed twist of 12.4 degrees between covalently linked cytosine base pairs, and the base stacking distance is 3.1 A. This is in general agreement with the NMR studies. A biological role for DNA in this conformation is suggested.
Crystal structure influence on friction and wear characteristics of binary tungsten-cobalt and molybdenum-cobalt alloy systems in vacuum
The crystal structures of alloys 61, X-40,X-50, 422-19, 6059, and Vitallium, derived from x-ray diffraction, are discussed. The alloys have been, or are being considered for use in gas turbine applications. The predominant phase was a solid solution of the face centered cubic type of the principal constituent elements.The lattice parameters were found to be between 3.5525 and 3.5662.
Friction and wear of hexagonal metals and alloys as related to crystal structure and lattice parameters in vacuum
Friction and wear of hexagonal metals and alloys as related to crystal structure and lattice parameters in vacuum
Crystal structures of Ni-rich rare earth/Ni phases, including high temperature forms