The Electric Oxygen

Sacks faces St. Petersburg and meditates, contemplating the bearded, prophetlike Mendeleev. 

Mendeleev, Osnovy Khimii (Principles of Chemistry), Tovarishchestva Obshchestvennaia Pol za for the Author, St. Petersburg, 1869. am grateful to Drs. Gregory S. Girolami and Vera V. Mainz for permission to use this image, and for helpful discussions. 

Mendelejeff, Annalen der Chemie Und Pharmazie, VIII. Supplementband, Leipzig and Heidelberg, 1872, pp. 133-229. (This paper was received from St. Petersburg in August, 1871). 

The Development of Modern Chemistry, Harper Row, New York, 1964, pp. 231-256. 

Everything in its Place—One Man s Love Affair with the Periodic Table, New York Times Magazine, April 18, 1999, pp. 126-130. 

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Plasma-deposited siUcon nitride contains large amounts of hydrogen, typically in the range of 20—25 atomic % H, and has polymer-like properties. The electrical resistivity of the film depends on the deposition temperature, the film stoichiometry, and the amounts of hydrogen and oxygen in the film. 

In Germany and Japan, pulverized quicklime is used in making self-fluxing sinters, partially replacing limestone. Granular dead-burned dolomite is stiU used to protect the refractory lining of open-hearth and electric furnaces, but not the basic oxygen furnace. Refractory time has declined with the... 

Oxygen also dissolves in the silicon crystal lattice, forming SiO which may radically affect the electrical properties of the silicon. Oxygen is usually unintentionally introduced during the crystal-growing operation in concentrations up to the solubility limit (ca 2.5 x 10 atoms/cm ). When... 

Both anatase and mtile are broad band gap semiconductors iu which a fiUed valence band, derived from the O 2p orbitals, is separated from an empty conduction band, derived from the Ti >d orbitals, by a band gap of ca 3 eV. Consequendy the electrical conductivity depends critically on the presence of impurities and defects such as oxygen vacancies (7). For very pure thin films, prepared by vacuum evaporation of titanium metal and then oxidation, conductivities of 10 S/cm have been reported. For both siugle-crystal and ceramic samples, the electrical conductivity depends on both the state of reduction of the and on dopant levels. At 300 K, a maximum conductivity of 1 S/cm has been reported at an oxygen deficiency of... 

In modem steel (qv) manufacture, pebble quicklime is used as a flux in the basic oxygen, basic open-hearth, basic Bessemer, and basic electric furnaces. 

The environment plays several roles in corrosion. It acts to complete the electrical circuit, ie, suppHes the ionic conduction path provide reactants for the cathodic process remove soluble reaction products from the metal surface and/or destabili2e or break down protective reaction products such as oxide films that are formed on the metal. Some important environmental factors include the oxygen concentration the pH of the electrolyte the temperature and the concentration of anions. 

HAZARD The inherent property of a substance capable of causing harm (e.g. toxicity, radioactivity, flammability, explosivity, reactivity, instability). In a broader context anything that can cause harm, e.g. electricity, oxygen-deficiency, machinery, extreme temperature. 

There are two process routes for making steel in the UK today the electric arc furnace and the basic oxygen converter. The latter requires a charge of molten iron, which is produced in blast furnaces. The raw materials for producing molten iron are iron ore, coking coal, and fluxes (materials that help the chemical process) - mainly limestone. 

The electric arc furnace (EAF) (together with the basic oxygen vessel) is one of... 

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