Coin identification

XRF is widely used in industrial applications where a large number of elements need to be determined quantitatively. It is used for continuous quality control in the steel industry (e.g., the determination of Mn, Cr, Ni, Co, etc., in the production of stainless steels), and also for casting quality of coins in the Royal Mint (where Cu, Ni, and Zn are continuously monitored). Geological applications include whole rock analyses and clay identification. The power industry uses it as pollution control management, measuring sulfur and heavy metal concentrations in fuels (coal, oil) and ash. 

Neutron activation analysis (NAA), based on the interaction of the object material with fast neutrons, has been used in the identification and determination of the content of elements present in pigments, coins and alloys, stone, glass, and pottery [26]. Multi-elemental analysis (about 20 elements) can be performed on small samples off less than 5 mg, with sensitivities in the ppm range. The requirement of a nuclear reactor, the handling of radioactive materials, and the time-consuming procedures required for preparing the samples are the main drawbacks of this technique. 

The identification of a chemical bond with a pair of electrons came from G. N. Lewis in 1916, and the term covalent bond was coined by Irving Langmuir. The Lewis structures for covalent bonds are still in use in the UK A-level syllabus, and it is the main purpose of this book to persuade new students that the time has come to make further progress with their understanding of bonding. 

Almost a decade before the term pheromone was coined, Roth and Willis (1952) conducted seminal experiments that characterized volatile and contact pheromones in cockroaches. Louis Roth s research integrated studies of endocrinology and behavior, and the influence of this approach was reflected in Barth s early articulation of the interplay between the endocrine system and sexual behavior. In later years cockroaches continued to serve as important models for invertebrate endocrinology (Scharrer, 1987 Tobe and Stay, 1985), but research on pheromones lagged, in part due to technical difficulties in sex pheromone identification. Below, we highlight some of the many issues yet to be resolved in the physiological and behavioral regulation of sex pheromone production and emission in cockroaches. 

The term chemoinformatics was coined in 1998-1999 and rapidly gained widespread use and, as F. K. Brown says [Brown, 1998], Chemoinformatics is the mixing of those information resources to transform data into information and information into knowledge for the intended purpose of making better decisions faster in the area of drug lead identification and organization. ... 

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