Barium history

The radioactive element is a silvery, shiny, soft metal that is chemically similar to calcium and barium. It is found in tiny amounts in uranium ores. Its radioactivity is a million times stronger that that of uranium. Famous history of discovery (in a shed). Initially used in cancer therapy. Fatal side effects. Small amounts are used in luminous dyes. Radium was of utmost importance for research into the atom. Today its reputation is rather shaky as its decay gives rise to the unpleasant radon (see earlier). In nuclear reactors, tiny amounts of actinium are formed from radium. 

Videman T, Nurminen M (2004) The occurrence of anular tears and their relation to lifetime back pain history a cadaveric study using barium sulfate discography. Spine 29 (23) 2668-2676... 

Holloway JR, Blank JG (1994) Application of experimental results to C-O-H species in natural melts. In MR Carroll, JR Holloway (eds.) Volatiles in magmas. Rev Miner 30 187-230 Holser WT (1977) Catastrophic chemical events in the history of the ocean. Nature 267 403 08 Holser WT, Kaplan IR (1966) Isotope geochemistry of sedimentary sulfates. Chem Geol 1 93-135 Holt BD, Engelkemeier AG (1970) Thermal decomposition of barium sulfate to sulfur dioxide for mass spectrometric analysis. Anal Chem 42 1451-1453 Hoppe P, Zinner E (2000) Presolar dust grains from meteorites and their stellar sources. J Geophys Res Space Phys 105 10371-10385... 

The natural history of chemistry consists since many centuries in empirical rules about the relative affinity of various elements. Though metathetical reactions are frequently used in preparation, the main origin is the filtering of insoluble precipitates, as when an aqueous solution of silver sulphate and another of barium iodide leave almost pure water in the filtrate ... 

People who smoke and those who have a history of lung disease may be at an increased risk of exposure by inhalation. Studies show that inhalation of dust from barium salts produces a mild, but lengthy, inflammatory response in the lungs of rats (Huston et al. 1952). A benign pneumoconiosis has been noted in cases of chronic, low-level exposure in humans (Doig 1976). Smoking and lung diseases may increase the intensity of this response in affected individuals. 

The discovery of fission was a complete surprise and also a great shock, because it shattered fundamental ideas of nuclear behavior that had guided the investigation. The surprise was evident in the events of December 1938. On December 10, Enrico Fermi was awarded the Nobel Prize in physics. He and his group in Rome had been the first to irradiate uranium with neutrons and to propose that transuranium elements had been formed in the process. In his Nobel lecture, Fermi was so confident of the first two, elements 93 and 94, that he referred to them by name ausonium and hesperium. But at that very moment, the Berlin team of Otto Hahn, Lise Meitner, and Fritz Strafimann was on the verge of identifying barium among the uranium products. By the end of the year, they understood that uranium had split, explained the fission process, and concluded that the transuranium elements were false. When Fermi published his Nobel lecture, he added a footnote to that effect, but by then ausonium and hesperium were themselves footnotes (if that) in the history of science. [1]... 

The barium finding was published by the chemists in Naturwissenschafien [34] and the fission theory by the physicists in Nature [35] a few weeks later. This emphasized the separations - chemistry from physics, experiment from theory, in different journals, in different languages. The separations were an artifact of Meitner s forced emigration and the politics of the time. From that time forward, the interdisciplinary nature of the discovery was obscured and its history distorted, not least by the award of the 1944 Nobel Prize in chemistry to Otto Hahn alone. [36]... 

A significant step in the history of the HTSs was the discovery in 1966 of superconductivity in the oxygen-deficient perovskite SrTi03 5, containing some barium or calcium substituted for strontium. Although the Tc value was very low (0.55 K), in retrospect it can be seen as the first superconducting ceramic. In 1979 a Tc of approximately 13 K was discovered for BaPb075Bi025O3, which also has the perovskite structure. 

History.—Hydrogen peroxide or, as it is sometimes termed, hydrogen dioxide, was first obtained by Thenard in 1818 m an examination of the dilute aqueous solutions formed by the action of vanous mineral acids on barium peroxide.1 In the early days of its investigation considerable confusion was caused by the similarity between hydrogen peroxide and ozone in aqueous solution.2... 

A 68-year-old woman, with a history of alcohol abuse and a leiomyoma of the stomach, aspirated barium sulfate and became dyspneic and developed hypoxia (Pa02 46mmHg). At bronchoscopy the bronchial mucosa was coated with barium and a chest X-ray showed heavy alveolar deposition of barium sulfate distributed over the entire lung, with some predominance in the lower zones. The patient developed a fever (39°C) and a leukocytosis (12 x 10 /I) the day after aspiration. She was given cefotiam 2000 mg and metronidazole 500 mg intravenously every 8 hours. The fever resolved within 2 days and Staphylococcus aureus was cultured from the bronchial fluid. She was discharged 2 days later, but the chest X-ray continued to show persistent alveolar deposition of the barium sulfate with only a slight improvement compared with the initial X-ray. 

Thus the history of analysis of petroleum and its products can only be suggested to have started during the second half of the nineteenth century. For example, in 1857 several aromatic hydrocarbons from Burma petroleum were identified by the formation of the barium salts of benzenesul-... 

Starting with the silicone elastomer hydrocephalus shunt in 1955, silicone elastomer has become widely used as a soft, flexible, elastomeric material of construction for artificial organs and implants for the human body. When prepared with controls to assure its duplication and freedom from contamination, specific formulations have excellent biocompatibility, biodurability, and a long history of clinical safety. Properties can be varied to meet the needs in many different implant applications. Silicone elastomer can be fabricated in a wide variety of forms and shapes by most all of the techniques used to fabricate thermosetting elastomers. Radiopacity can be increased by fillers such as barium sulfate or powdered metals. It can be sterilized by ethylene oxide, steam autoclave, dry heat, or radiation. Shelf-life at ambient conditions is indefinite. When implanted the host reaction is typically limited to encapsulation of... 

I none and Yasui (1987) have calculated the Raman spectrum of barium dihafnate glass from the time history of the polarizability tensor in a MD simulation between... 

A. Lavoisier included lime and magnesia into The Table of Simple Bodies but excluded potassium and sodium hydroxides believing that they had complex composition and their nature had to be further studied. One might say that history was unjust to these elements, for barium, for instance, was isolated in a metallic state simultaneously with them, but had been discovered mnch earlier. However, history is a wayward lady. The discovery of sodium, potassium, magnesium, and calcinm is interesting in that it was made possible by electric cnrrent being successfully used for the first time. This marked the birth of the electrochemical method, a subsidiary to the chemical analysis. Subsequently, electrolysis of melted compounds made it possible to obtain other metals discovered earlier in their compounds. 

Production, concentration and pressure histories of tertiary barium hydroxide flood as a function of pore volumes throughput. 

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