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Characterization and beneficiation of dry iron ore processing plant reject fines of Khondbond region, India, was investigated. Different characterization techniques viz. size analysis, size-wise chemical and density analysis, X-ray diffraction analysis, sink-float analysis, thermo gravimetric analysis, scanning electron microscopy, and QEMSCAN were carried out. Based on characterization results, two process flow sheets comprising wet screening followed by conventional gravity concentration and two stage classification with different beneficiation routes were used to recover the iron values from reject fines containing 58.73% Fe, 5.54% Al2O3, and 6.6% SiO2. Finally, suggested flow sheet comprising of two stage classification and advance gravity concentration followed by the combination of grinding, classification, and froth flotation produced iron concentrate of 2.36% Al2O3 with 75.8% yield which can be used in sinter/pellet making.

Flow sheet development of dry beneficiation of coking coal fines of size −1.0 + 0.1 mm using controlled vibro fluidization is the aim of the present study. Process conditions affecting the separati...

The interaction of dextrin and guar gum with pyrite has been investigated through adsorption, flotation, and electrokinetic measurements. The adsorption densities of the polysaccharides onto pyrite reveal a region of higher adsorption density in the pH range 7.5-11, with a maximum around pH 10 for both polymers. The isotherms exhibit Langmuirian behavior. The adsorption density of guar gum onto pyrite is higher than that of dextrin. Electrokinetic measurements indicate a decrease in the electrophoretic mobility values in proportion to the concentration of the polymer added. Co-precipitation tests confirm polymer-ferric species interaction in the bulk solution, especially in the pH range 5.5-8.5. The pH range for higher adsorption, significant co-precipitation, and appreciable depression of pyrite encompass each other. XPS and FTIR spectroscopic studies provide evidence in support of chemical interaction between hydroxylated pyrite and the hydroxyl groups of the polymeric depressants. Copyright 2000 Academic Press.

An epidemic of encephalitis occurred in the eastern, paddy growing districts of Haryana state between July and November 1990. One hundred and eighty-two patients with encephalitis were admitted to different hospitals in Haryana and 118 of them expired (mortality rate 64.8%); 88% of the patients were children. The male to female ratio was 2. 3. 1. IgM class of antibodies to Japanese Encephalitis (JE) Virus could be demonstrated in the CSF and/or sera of 3 surviving and 2 fatal patients of the 19 patients studied. This is the first detailed report on an epidemic of encephalitis in North-Western part of India. Serologically proven cases of JE are being reported, for the first time, from this region.

Inhalt: 436 Ejakulate von 5 Braunviehstieren wurden mit 2 verschiedenen Verdunnern versetzt, denen Tranquilizer beigegeben worden waren. Verdunnungsgrad und Narkobiotika-Konzentrationen wurden variiert und die Einflusse dieser Variablen auf die Lebensdauer bei + 4° C gelagerter Spermien — im Vergleich zu Kontrollproben — rechnerisch ermittelt. Contents: Two extenders were used in various dilutions on 436 ejaculates of 5 brown-swiss bulls. Several tranquilizers were tested in various concentrations. The effects of these variables on sperm survival at 4° C relative to control samples were investigated. Zusammenfassung 436 Samenproben von 5 Stieren wurden dahingehend gepruft, ob durch die narkobiotische Wirksamkeit von Tranquilizern (Largactil, Combelen, Truxal und Bay-Va-1470) eine Verlangerung der Uberlebensdauer bei + 4° C gelagerter Spermien erreicht werden kann. Die Untersuchungen ergaben, das alle im Versuch angewandten Tran-quilizer die Lebensdauer der Samenzellen im Vergleich zu den Kontrollen verlangern. Der positive narkobiotische Effekt war abhangig vom Verdunner, dem Grad der Verdunnung und der Tranquilizer-Dosierung. Die besten Ergebnisse wurden ermittelt, wenn die Samenproben (0,5 ml)im Verhaltnis 1:9 bzw. 1:12 mit Citrat-S verdunnt wurden, dem Largactil in Mengen von 0,1 bzw. 0,2 mg zugesetzt worden war.

Adsorption, electrokinetic and flotation studies have been carried out to investigate the interaction of guar gum with chalcopyrite. The adsorption density of guar gum onto chalcopyrite shows a weak adsorption maximum at pH 9.5. The adsorption isotherms exhibit Langmuirian behaviour. The electrophoretic mobilities of chalcopyrite are decreased in proportion to the added concentration of guar gum. Flotation tests reveal that guar gum depresses chalcopyrite in agreement with the adsorption data. Dissolution experiments indicate release of lattice metal ions from chalcopyrite, while co-precipitation and conductivity tests confirm guar gum-metal ion interaction in the bulk solution. The pH of maximum co-precipitation between guar gum and copper species is observed in the range 9-9.5. The adsorption process is governed primarily by chemical interaction between the hydroxyl groups of guar gum and hydroxylated chalcopyrite apart from hydrogen bonding. Fourier Transform Infrared Spectrometer (FTIR) and X-...