N3-Ligdnd constant, PL/V ( & 0.05 V cstimated error) + 1.46 1.40 0.00 -0.07 -0.10 -0.35 -0.38 -0.40 -0.4:) -0.58 -0.59 -0.77 -0.78 -0.88 -1.00 -1.16 -1.15 -1.17-1.19 -1.22 -1.26 -1.55measured and values which we have deduced by intcrpolation from data from other series of Complexes (see below). These ligand constants refer t o L as a twoelectron donor ligand which must be added t o the 16electron moiety to give the closed-shell 18-electron complexes [M,L], x bonding being ignored. Considered in this way the nitride ligand in [M,N] is formally N+, the nitrosyl NO+, and the hydride H-. From Table 1 it can be seen that charged ligands occupy the extremes of the scale. The weakest Q donors with strong x-acceptor

Stationary dual-beam hydroacoustics and visual point count surveys were used in tandem to measure the density, target strength, and species composition of fishes associated with a petroleum platform in the northern Gulf of Mexico. Fish densities ranged from 0 to 10.5 fish · m-3 during monthly sampling trips from January 1991 to May 1992. Density and target strength were spatially and temporally variable. Target strengths varied significantly with side of the platform, month, and east and north current vectors. Density varied significantly with platform side, month, east current vector, and depth. Density and target strength did not change over 24 h periods or with water temperature. Fish densities were highest adjacent to the platform and decreased significantly beyond 16 m. Approximately 1990 - 28<|>100 fish were associated with the platform depending on the month. A total of 19 species were observed at the platform, with Chaetodipterus faber, Caranx fusus, Seriola dumerili, Balistes capriscus,Lutjanus campechanus, andArchosargus probatocephalus constituting 97% of observed fishes. Based on our results, we conclude that the fishes associated with a petroleum platform conform with the open nonequilibrium hypothesis proposed for fishes in coral reef habitats.

The increased production of biodiesel has resulted in the overproduction of glycerol. Many researchers have begun investigating new uses for glycerol, including its conversion to fuel additives. In this paper, glycerol has been reacted with furfural to yield the corresponding acetal. This condensation reaction is carried out under neat conditions with 5-fold excess of furfural, and a number of homogeneous Lewis acids and heterogeneous solid acids as catalysts. Reactions are routinely carried out at 100 °C, allowing for yields up to 90%. The addition of a dry stream of nitrogen gas purging the headspace was found to improve yields and allowed for a reduction in the excess amount of furfural. These reaction methods are applicable to crude glycerol, affording up to 80% yield with short reaction times. The isolated acetal products can be hydrogenated, and the free hydroxyl group can subsequently be acetylated. The resulting materials have been investigated as additives to biodiesel, aiming to improve the low temperature properties. While there was no benefit to the low temperature properties, we have no evidence that would preclude the use of these materials as biodiesel additives.

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