Chemical composition of smectite-bearing basal metalliferous sediments from DSDP Leg 9

The mineralogy and P, Fe and Mn contents of basal metalliferous and nonmetalliferous sediments of two Deep Sea Drilling Project cores (Sites 77 and 80) were investigated. When compared with superjacent nonmetalliferous material, basal metalliferous sediments are significantly enriched in P, Fe and Mn. Among the phases present in the metalliferous sediment samples are a poorly-crystalline Fe-rich smectite and X-ray amorphous Fe oxyhydroxides. P is associated primarily with the oxyhydroxides. Adsorption of phosphate on smectite does not seem to play any role in the uptake of P by metalliferous sediments. An estimate of the removal of P by on- and off-ridge metallogenic deposition suggests that this process strongly affects the overall geochemical balance of phosphorus in the World Ocean.

RANN 2 : Realizing knowledge as a resource : proceedings of the second Symposium on Research Applied to National Needs, Washington, D.C., November 7-9, 1976.

"NSF 77-51" through "NSF 77-56."

West Valley cooperative agreement [microform] : hearing before the Subcommittee on Investigations and Oversight of the Committee on Science and Technology, U.S. House of Representatives, Ninety-seventh Congress, first session, July 9, 1981.

"No. 26."

Economic and social conditions in Puerto Rico : hearings before a Subcommittee of the Committee on Territories and Insular Affairs, United States Senate, Seventy-seventh Congress, second session, pursuant to S. Res. 309, a resolution authorizing an investigation of economic and social conditions in Puerto Rico, Washington, D.C. December 7, 8, 9, and 17, 1942.

Dennis Chavez, chairman of subcommittee.

Fragm. lat. I 77 - Graduale (Fer.IV - VI et Sabb. aus der Quatemberwoche der Quadragesima)

Trägerband: 'Scriptum Thom. Aquin. 1490'

Different behavior of nitrenes and carbenes on photolysis and thermolysis: Formation of azirine, ylidic cumulene, and cyclic ketenimine and the rearrangement of 6-phenanthridylcarbene to 9-phenanthrylnitrene

Flash vacuum thermolysis (FVT) of 9-azidophenanthrene 8, 6-(5-tetrazolyl)phenanthridine 18, and [1,2,3]triazolo[1,5-f]phenanthridine 19 yields 9-cyanofluorene 12 as the principal product and 4-cyanofluorene as a minor product. In all cases, when the product is condensed at or below 77 K, the seven-membered ring ketenimine 24 is detectable by IR spectroscopy (1932 cm(-1)) up to 200 K. Photolysis of Ar matrix isolated 8 at lambda = 308 or 313 nm generates at first the azirine 26, rapidly followed by the ylidic cumulene 27. The latter reverts to azirine 26 at lambda > 405 nm, and the azirine reverts to the ylidic cumulene at 313 nm. Nitrene 9 is observed by ESR spectroscopy following FVT of either azide 8, tetrazole 18, or triazole 19 with Ar matrix isolation of the products. Nitrene 9 and carbene 21 are observed by ESR spectroscopy in the Ar matrix photolyses of azide 8 and triazole 19, respectively.