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Showing 1 to 20 of 55 for “"malachite"”.
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Geochemical-spectrographic prospecting at the Malachite Mine, Jefferson County, Colorado
Includes bibliographical references.
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The kinetics of hydrolysis and the electronic absorption spectra of some sterically hindered basic dyes
A comprehensive series of derivatives of Malachite Green substituted in the phenyl ring with silicon, phosphorus, sulphur, nitrdgen or oxygen containing groups have been synthesised. Their absorption spectra have been measured in 98% acetic acid solution and compared with that of Malachite Green. …
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The chemistry of some polysubstituted derivatives of di - and triphenylmethane dyes
Several series of disubstituted derivatives of Malachite Green containing chloro, fluoro, methoxy and methyl groups in the phenyl ring have been synthesised and their respective visible absorption spectra compared with that of Malachite Green. In most cases where steric effects are unimportant an …
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Fungal Control Methods, Diets and Water Temperatures Used to Culture Paddlefish, Polydon spathula
… at 1667 mg/1 and later at 833 mg/l; and with malachite green, for 2 min daily at 65 mg/1, to control fungus. Hatching success, determined by estimating numbers of fry at swim-up, was 16.6% for the eggs treated with formalin and 21.8% for the eggs treated with malachite green. Hatching success …
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Etude de la flottabilité de la malachite à l'aide de l'amylxanthate de potassium et d'un acide gras. (Cas d'étude: Flottation du minerai oxydé de Kamfundwa au Katanga en RDC)
… is oriented towards studying the floatability of malachite with xanthate and fatty acids collectors. It focuses from one side on aspects related to surface phenomena and collector attachment mechanisms and on other side on improvement of processing flowsheet at industrial scale. The first part of …
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An Investigation of Copper Recovery from a Sulphide-Oxide Ore with a Mixed Collector System
… a natural porphyry copper ore with bornite and malachite was investigated via fundamental work with pure minerals and a bench-scale testing regime. The processing of the test ore was problematic due to a mineral assemblage that caused prevalent slime generation. Fundamental adsorption, …
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The chemistry of some heterocyclic analogues of triphenylmethane dyes
… has been synthesised in which the phenyl ring of Malachite Green has been replaced by a 5- or 6- membered heterocycle containing nitrogen, oxygen or sulphur as hetetâacoins. The visible absorption spectra of the dyes have been correlated with the electronic and structural features of the …
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Alkyl, alkenyl and cycloalkyl substituted triphenylmethane dyes
A series of Malachite Green derivatives containing alkyl an alkenyl substituents in the 2-, 3-. and 4- positions has been synthesised. Their respective visible absorption spectra have been correlated with the electronic and steric effects of the methyl, ethyl, propyl, butyl and vinyl substituents …
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The chemistry of some basic triphenylmethane dyes
… with two identical terminal groups, analogues of Malachite Green, and those with three terminal groups, the Crystal Violet series. N,N-dimethylamino--, N,N-diethylamino-, pyrrolidino-,piperidino and morpholino- grou'ps have been slected as terminal groups in order to give a wide variation in both …
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A kinetic and photochemical study of some basic dyes
… range of substituted oxygenbridged analogues of Malachite Green. The dye perchiorates have been prepared from the corresponding carbinols or leuco bases. The influence of the terminal group and the bridging unit together with the effects of substituents on the electronic absorption spectra of the …
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A study of the flotation characteristics of a complex copper ore
… in LQ ore was present as chrysocolla, 1.3 % as malachite and 5.8 % as chalcopyrite and therefore LQ ore required alternative flotation methods for the recovery of the oxide minerals. Comparison of slug sulphidisation and controlled potential sulphidisation (CPS) of LQ ore have shown that CPS …
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The electronic absorption spectra of di- and tri-arylmethane dyes containing fluorine
… derivatives of this compound. Novel analogues of Malachite Green, Crystal Violet and Michler's Hydrol Blue have been prepared containing terminal piperidino- and pyrrolidino- groups. Differences in the electronic absorption spectra of the parent systems have been correlated with the varying …
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Electronic absorption spectra of basic dyes containing terminal diethylamino and morpholino groups
… parent dyes have been compared with those for Malachite Green and the differences have been interpreted in terms of the relative basicity of the terminal groups. Where substitution occurs in the meta- and para-positions of the phenyl ring, it has been shown that the wavelength of maximum …
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The Chemistry of some Di- and Tri-Phenylmethane dyes
… a comprehensive series of novel, unsymmetrical Malachite Green type dyes containing different amino substituents in the 4-positions of the phenyl rings and a series of symmetrical Michier's Hydrol Blue type dyes. Both series of dyes have been synthesised from the relevant carbinols or hydrols. …
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Studies on the host range and chemical control of fungi associated with diseased tropical fish
… tested would permit sustained fish culturing. Malachite green was the most effective fungicide tested, being functional in concentrations as low as 2 ppm.
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New photosensitisers for photodynamic therapy
… previously unknown benzopyranyl derivatives of Malachite Green has also been achieved and that of known and new 2,3-dimethyl analogues of Malachite Green and Crystal Violet has been improved. The UV-visible absorption spectra of these dyes have been recorded in acetic acid-water mixtures and …
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Preparation and Characterization of Cu-ZnO Catalysts for Methanol Synthesis
… beispielsweise die der Präkursorphase Zink-Malachite, Hinweise auf die spätere Aktivität. Präkursoren, calcinierte und reduzierte Proben wurden mit verschiedenen Methoden charakterisiert (XRD, XRF, TG-MS, N2 physisorption, TPR, N2O-RFC, UV-Vis, XAS, XPS, SEM, TEM) und für ausgewählte Proben …
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Activated Carbon from North Dakota Lignite
… 4 percent of the color from a stock solution of malachite green indicator while many of the products of this investigation removed 75 to 85 percent.</p><p>The analysis of variance of the results of the two designs used indicate that the effects of residence time between 6 minutes to 24 minutes is …
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The stratigraphic and structural controls on copper-gold mineralization at Cassenha hill prospect, within the Archean to Paleoproterozoic Angolan shield, Congo craton, South Western Angola
… and supergene ore (stage II) consisting of malachite ± azurite ± chrysocolla, which represents the prevalent mineralization at the prospect. The δ 18O value of quartz veins range from +12.81 to +13.53‰, while the δD of chlorite minerals range from -51 to -45‰. Therefore, assuming fluid-rock …
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