Bogs, lead

Aza-bicyclic compound 234, in presence of TFA, undergoes A-BOG cleavage and subsequent intramolecular cycliza-tion/dehydration leading to the benzo-annulated dihydropyrrolizine 235, in 92% yield (Scheme 60) <2004T7367>. 

WAD. The mineral wad, sometimes called bog manganese, occurs in amorphous masses, and consists of mixtures of manganese oxides, MnOi and MnO, and oxides of odter metals such as copper, lead, cobalt, and iron. It is bluish- to brownish-black, usually soft enough to soil the fingers and often porous and light. It is not a distinct mineral species. 

Adipocere formation has been observed in a variety of burial environments, including lead-lined coffins (Mant 1987), peat bogs (Evershed 1992), ice glaciers (Mayer, Reiter, and Bereuter 1997), and submerged locations (Kahana et al. 1999), and consequently numerous principles governing its... 

Selective protection of 3-aminopyrazoles can lead to a variety of 3-acylaminopyrazole derivatives. 3-Aminopyrazole 317 could be selectively protected at N-2 giving BOC-protected pyrazole 318, which reacted with various acyl chlorides followed by BOG removal to provide 3-acylated pyrazoles 319 (Scheme 30) <2003TL4491>. Other protecting groups such as carbobenzyloxy (Cbz), benzyl (Bn), and SEM could be introduced at the N-2 position with biphasic conditions using potassium hydroxide as the base. A simple procedure for the BOG protection of H-1 of 3-aminopyrazoles has been described where 3-acylaminopyrazole derivatives could be prepared in good yields <2005TL933>. 

Shotyk W., Cheburkin A. K., Appleby P. G., Erankhauser A., and Kramers J. D. (1996) Two thousand years of atmospheric arsenic, antimony, and lead deposition recorded in an ombrotrophic peat bog profile. Jura Mountains, Switzerland. Earth Planet. Sci. Lett. 145, El -E7. 

A major issue in clinical research today is that of the overwhelmed study coordinator. Because of the ever growing number of details that comprise clinical studies, coordinators can easily become bogged down and, ultimately, very frustrated. This situation can lead to a decline in work quality or a high level of employee turnover. According to a recent survey, 53% of study coordinators have been in their jobs for three years or less (Borfitz, 2004). This poses real challenges in terms of experience level, knowledge of GCP and familiarity with site operations. 

SEL/BOG] Selivanova, N. M., Boguslavskii, R. Y., Solubility of lead selenate in aqueous solutions of alkali metal selenates, Zh. Fiz. Khim., 29,... 

Lead emissions When Rome was at its peak in lead production, it produced 80 000 metric tons every year. In studies of changes in atmospheric composition throughout history, researchers measured residues of lead from ancient Rome and Greece foimd in British peat bogs and in Swedish lake sediments. 

Temporal trends of the ambient concentration and deposition flux of particulate trace metals are now available for various sites (Pirrone etal. 1995 Var etal. 2000 Kemp 2002). From their measurements at seven urban sites across the metropolitan area of Detroit in the 1982-1992 time period, Pirrone et al. (1995) reported downward trends for Fe, Pb, Cr, Cd and Be, and an upward trend for Zn, Ni and Hg. As was reported for lead concentrations in ice layers (Boutron et al. 1995) and peat bogs (Shotyk et al. 1996), a significant reduction of the Pb content in airborne particulate matter was observed in the past two decades at different urban sites in Denmark (Kemp 2002). 

Shotyk W, Weiss D, Heisterkamp M, Cheburkin A, Appleby P and Adams F (2002) New peat bog record of atmospheric lead pollution in Switzerland ... 

A low redox potential - as in bog soils -leads to the formation of H2S, which may be bound to sulfides of iron or may volatilize. Fe-sulfides are the cause for the black color in reduction zones of soils. Sulfide is the stable form under strong reducing conditions, but when changing to aerobic conditions sulfuric acid is formed, and this leads to soil acidification. Both the oxidation and reduction of sulfur compounds involve autotrophic bacteria (sulfur bacteria). 

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