precursor


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precursor

a chemical substance that gives rise to another more important substance
References in classic literature ?
One day, taking a pair of shoes to be mended, he saw the cobbler's wife seated by the fire, suffering from the terrible symptoms of heart-disease and dropsy, which he had witnessed as the precursors of his mother's death.
Curious to discover of what strange events these novel sounds might be the precursors, and not a little desirous to catch a sight of the instruments which produced the terrific noise, I accompanied the natives as soon as they were in readiness to depart for the Taboo Groves.
The followers of Chaucer, and the precursors of Shakespeare, are alike real persons to him--old Langland reminding him of Carlyle's "Gospel of Labour.
The mediaeval burgesses and the small peasant proprietors were the precursors of the modern bourgeoisie.
These two pursuits have thus in a manner been the pioneers and precursors of civilization.
All were apprehensive of worse to come, and this was especially true of the seamen who recalled all sorts of terrible omens and warnings that had occurred during the early part of the voyage, and which they could now clearly translate into the precursors of some grim and terrible tragedy to come.
In "Ecco Homo" he is careful to enlighten us concerning the precursors and prerequisites to the advent of this highest type, in referring to a certain passage in the "Gay Science":--
The Boeing Company has obtained a patent for a method for applying a silicon oxy-carbide coating onto a substrate comprised of the steps of introducing a shielding gas and a plasma-source gas to an atmospheric plasma device to generate an atmospheric plasma; introducing a cyclic organosiloxane precursor to the atmospheric plasma, the cyclic organosiloxane precursor being carried by a carrier gas; and while the cyclic organosiloxane precursor is being introduced to the atmospheric plasma, positioning the substrate relative to the atmospheric plasma device such that the atmospheric plasma deposits the silicon oxy-carbide coating onto the substrate.
Summary: The eighth International Hemaya Forum on Drugs, which will start here today in the presence of Lt-General Dhahi Khalfan Tamim, Commander-in-Chief of the Dubai Police, and experts from 16 countries, will focus on precursor chemicals that are essential to the production of a controlled substance.
It added that some of the sitea[euro](tm)s textile fibre production lines will be transformed into precursor lines and gradually extended.
The natural enantiomer of the RNA precursor molecules formed a crystal structure visible to the naked eye.
Furthermore, the differences in neonatal outcomes based on precursor type suggest that "the underlying pathology for precursors is an important determining factor in neonatal morbidity.