History of molecular biology Crick and Watson built physical models using metal rods and balls, in which they incorporated the known chemical structures of the nucleotides, as well as the known position of the linkages joining one nucleotide to the next along the polymer. At King's College Maurice Wilkins and Rosalind Franklin examined X-ray diffraction patterns of DNA fibers. Of the three groups, only the London group was able to produce good quality diffraction patterns and thus produce sufficient quantitative data about the structure. In 1948 Pauling discovered that many proteins included helical (see alpha helix) shapes. Pauling had deduced this structure from X-ray
X-ray crystallography polymethylcyanoacrylaon of Boin crystal parameters. Heating or burning of bones causes recognizeable changes in the bone mineral that can be detected using X-ray diffraction (XRD) techniques. During the first 15 minutes of heating at 500 °C or above, the bone crstals began to change. At higher temperatures, thickness and shape of crystals of bones appear stabilized, but when the samples were heated at lower temperature or for shorter period, XRD traces showed extreme changes in crystal parameters. X-ray diffraction has been demonstrated as a method for investigating the complex structure of integrated circuits. X-ray crystallography X-ray crystallography is a technique