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Metal-organic matter interactions in the formation of an oil shale deposit
(Elsevier, 1990)
An attempt was made to distinguish metal-organic matter interactions in two types of sulfate-reducing environments, mild (MR) and strong sulfate-reducing (SR), in the Aleksinac oil shale deposit (Oligocene-Miocene). Samples ...
Depolarization end point can glassy carbon electrodes: Microscale coulometry of thioglycollic acid
(Wiley, 1991)
An externally unpolarized twin couple of glassy carbon electrodes, undergoing different pretreatments, and connected to nothing but a recorder, was engaged for simple and fast end‐point detection of electrometric titrations ...
Application of glassy carbon substrated cyanide‐sensitive electrodes in determination of cyanide and mercaptan levels of wastewater
(Wiley, 1993)
Quantities of free and complex cyanides and mercaptans were determined in wastewater. Levels of free and complex cyanides were determined after previous oxidation of mercaptans by hydrogen peroxide. The procedure used for ...
Fulvic acid characterization in an alluvial sediment sequence: differences between clay and sand environments
(Elsevier, 1992)
Fulvic acids (FAs) from the whole Quaternary sequence (to a depth of 26 m) of the alluvial sediment of the Sava river (taken from a site in Novi Beograd, Belgrade, Yugoslavia) were investigated with the aim of examining ...
The initiation of dendritic growth of electrodeposited copper on a rotating disc electrode with changing copper concentration and diffusion layer thickness
(Elsevier, 1992)
It is shown that the critical overpotential of dendritic growth initiation increases with increasing copper concentration under identical hydrodynamic conditions, as well as with increasing rotation speed to the rde (rotating ...
Electrochemical Deposition and Dissolution of Alloys and Metal Composites—Fundamental Aspects
(Springer Science and Business Media LLC, 1995)
It is general experience in materials science that alloys can exhibit qualities that are unobtainable with the parent metals. This is true of electroplated deposits as well. Thus, such properties as hardness, tensile ...
Substituent efects on the carbon-13 chemical shifts in α-phenylpyridylacrylic acids
(Elsevier Science Publishers B.V., 1992)
The 13C N.M.R. spectra of some substituted α-phenylpyridylacrylic acids, α-phenyl, α-(3-pyrydyl) and α-(3-pyrydyl-N-oxide) cinnamic acids were determined in deuterated dimethyl sulfoxide (d6-DMSO). It has been shown that ...
Sesquiterpene lactones from Achillea crithmifolia
(American Chemical Society, 1994)
The isolation of three highly oxygenated guaianolides, desacetyl-1α-4α- dihydroxybishopsolicepolide [1], its 4β-hydroxy epimer 2 (a new compound), and 1β,2β:3β,4β-diepoxy-8α,10α-dihydroxyguai-12(13)-en-12,6α-olide [3], ...
Sesquiterpene lactones from Achillea crithmifolia
(Elsevier, 1991)
The isolation of guaianolides rupicolin-A, rupicolin-B, their acetates and a new germacranolide 1β,10α-epoxy-3β,9β-diacetoxy-11α,13-dihydrocostunolide, identified by means of PS DQF COSY and PS NOESY, from Achillea ...
Regioselectivity in Cyclofunctionalization of Olefinic Alcohols with Benzeneselenenyl Halides at Different Temperatures
(Wiley, 1992)
The regioselectivity in cyclofunctionalization of some acyclic olefinic alcohols with benzeneselenenyl halides (PhSeCl and PhSeBr) at different temperatures (−78°C, 0°C and room temperature) is investigated. It has been ...