The fate of coccoliths at 48°N 21°W, Northeastern Atlantic.

As part of the Joint Global Ocean Flux Study Program (JGOFS) North Atlantic Bloom Experiment (NABE), coccolithophore fluxes were recorded over one-year period, from April 1989 to April 1990. Three vertically moored sediment traps, synchronized on a 14-day interval, were deployed at 48 °N 21 °W at three water depths, at 1, 2 and 3.7 km (sea floor at 4.4 km). We present the results on the vertical variability of coccolith and coccosphere fluxes through the water column. Calcium carbonate was the largest component of the total mass flux, followed by articulate organic matter and opal. Coccolith and coccosphere seasonal fluxes followed the seasonality of the biogeochemical particle fluxes at all three depths, with maxima occurring during the spring particle 'bloom'. The decrease in correlation between coccosphere and coccolith fluxes with depth (from r = 0.98 at 1 km depth to 0.60 at 3.7 km depth) documents that disaggregation of the coccospheres occurs during settling in the deeper part of the water column between 1 and 3.7 km water depth. Annual coccosphere and coccolith fluxes were 1.5 x 1

Study of the deposition and Raman and XPS characterization of a metal ion tetrasulphonated phthalocyanine layer at gold surfaces: density functional theory calculations to model the vibrational spectra

This paper describes the electrodeposition of Cu(II), Fe(III) and Al(III) tetrasulphonated phthalocyanine tetrasodium salts (Cu(II)TSPc, Fe(III)TSPc and Al(III)TSPc) at gold electrodes. Experimental evidence was provided that all MTSPc’s are deposited by using Raman spectroscopy and X-ray photoelectron spectroscopy. The modified electrodes are a useful tool for electrocatalysis and electroanalysis. The vibrational spectra were modelled using density functional theory (DFT) calculations. One specific band in the Raman spectra is highly sensitive to the metal ion, indicating a relationship between cavity size of the MTSPc’s and frequency of this Raman band. Keywords: Gold, Electrodeposition, Phthalocyanines, XPS, Raman spectroscopy, DF