Black mud

This compound is considered to be the electrolyte which on decomposition forms the two gases and a double potassium platinum fluoride which is deposited as a black mud. This hypothesis has been devised to explain why the initial stage of the electrolysis is irregular and jerky, and only after the lapse of an hour, when the substances in soln. are in sufficient quantities to make the passage of the current regular, is the evolution of fluorine regular. 0. Ruff 1 has shown that ammonium fluoride can be used in place of the potassium salt. 

A labile phase of iron disulphide occurs in nature under the name melnikovite It is a black, finely divided substance which impregnates certain miocene clays in Russia, and differs in many respects from the black hydrated sulphide of iron usually found in black muds of lakes. In composition it corresponds to the formula FeS2. It is magnetic, and its true density is probably 4 2 to 4 3. Cold, dilute hydrochloric acid readily attacks it, evolving hydrogen sulphide. It has probably been derived from a colloidal deposit of an iron sulphide.3... 

Stams A. J. M. and Hansen T. A. (1984) Fermentation of glutamate and other compounds by Acidaminobacter hydrogenoformans gen. nov. sp. nov., an obhgate anaerobe isolated from black mud. Studies with pure cultures and mixed cultures with sulfate-reducing and methanogenic bacteria. Arch. Microbiol. 137, 329—337. 

Thermi, Kyllini, Boaris A, black mud. The corresponding classes of... 

The queen offers a robe edged with gold to the naked man, who is standing up to his knees in black mud. A transparent red helmet covers his head, all but the profile. His right arm, neck, and... 

Black mud samples were taken from an arsenic-contaminated reed bed in Bendigo, Victoria, Australia, for the purpose of isolating an arsenate/sulfate-reducing bacterium (9). Bendigo is found approximately 100 km east of Ballarat (see Sec. 

Fio. 2. (a) A piece of asphalt from the floating blocks, Dead Sea. (b) A sediment core of black mud from the Dead Sea Coast, (c) A person sinking teough the carbonate crust, Dead Sea coast, (d) Large blocks of asphalt strewn along the Dead Sea coast near Bin Gedi. 

Sedimentary matter in many lakes tends to be rich in organic matter. A significant example of accumulation of such black mud is the large but shallow Lake Okeechobee in south-central Florida. This lake has an area of 1,750 km and a maximum depth of about 4.5 m below mean sea level. Figure 27.2 shows the thickness contours of the mud deposit. The volume of mud is estimated to be about 193 X 10 Such muds can be the primary carriers of sorbed chemicals that... 

Fig. 27.2. Lake Okeechobee in south-central Florida and contours of black mud thickness in cm...

Fig. 27.12. Some lakes and other sites in Florida laden with black mud or muck (adapted from...

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