Wyniki wyszukiwania - Biblioteka Nauki

Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl

Ograniczanie wyników

Znaleziono wyników: 3

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: carboxymethyl cellulose

Sortuj według:

Ogranicz wyniki do:

Dispersion of sodium phytate on muscovite and the implications for arsenopyrite flotation

100%

Zou D. , Wang Z. , Zhao K. , Xu Y.

tom Vol. 58, iss. 6

art. no. 154951

The effective flotation separation of sulfides and sliming silicate minerals is always a difficult problem. In this paper, the selective flotation of arsenopyrite from muscovite was studied by using sodium phytate (SP) as dispersant, and the mechanism was investigated through SEM/EDS, zeta potential, FTIR and XPS measurements. Single mineral flotation results showed that with the increasing isoamyl xanthate (IAX) dosage the recovery of arsenopyrite increased, until 8×10−5 mol/L IAX (79.40% recovery, pH=7), after that it decreased slightly. While muscovite floated poorly at any IAX concentration. For the mixed minerals, arsenopyrite recovery was only 54.63% while that of muscovite was 42.70%, which was attributed to the coverage of muscovite on arsenopyrite surface. When 6×10−5 mol/L SP was added into the mixed minerals system, the recovery of arsenopyrite recovered to 68.26% while that of muscovite was 8.48% (approximate the value of the single mineral). SEM/EDS results showed that SP could disperse muscovite and prevented its coverage on arsenopyrite surface. Zeta potential results showed that the electrokinetic potential of muscovite and arsenopyrite decrease from -26.60mV to -39.01 mV and from -26.90 mV to -27.84 mV at pH=7, respectively. It was obvious that the negatively charged phytate ions selectively adsorbed on the surface of muscovite. FTIR and XPS resulted co-proved the chemisorption of SP with active sites on muscovite while arsenopyrite spectrum did not change significantly, which was consistent with flotation and zeta potential results. The selective adsorption of SP on muscovite compared to arsenopyrite was responsible for the effective separation of them.

Study of the Effect of Intensity of Vibrations and Temperature on the Cooling Characteristics of Quenching Media

100%

Perju M.-C. , Nejneru C. , Burduhos-Nergis D. D. , Vizureanu P. , Minciuna M. G. , Sandu A. V.

2023

tom Vol. 68, iss. 3

997--1002

Quenching technology requires the use of media with different cooling intensities and various shapes of cooling curves that show different particularities compared to that of conventional media such as water, oil, or emulsions. The use of synthetic quenching media is relatively new and also has multiple advantages such as non-flammability, safety in use and low cost. In this study, the cooling media tested was obtained by mixing 2 wt% carboxymethyl cellulose with 2 wt% NaOH in one litter of water. Moreover, three different temperatures (20°C, 40°C and 60°C) of the quenching media were evaluated. By dissolution in water, a synthetic solution with low viscosity, surfactant and lubricant was obtained. Because carboxymethyl cellulose is a biodegradable organic material, that is obtained as a by-product in the manufacture of paper, a basic substance with a preservative effect was added. According to this study, both the variation diagram of the heat transfer coefficient and the diagram of the cooling rates, during the cooling stages give important indications regarding the use of a liquid cooling medium for quenching.

Degradation of cellulose by nitrogen-fixing strain of Bacillus polymyxa

72%

Gorska E. , Tudek B. , Russel S.

nr 2