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Copyright of Revista Cientifica de la Facultade de Veterinaria is the property of Universidad del Zulia, Facultad de Ciencias Veterinarias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Since the grinding and chemical reagents required for flotation are expensive, coarse particle flotation reduces grinding costs and makes the subsequent process more accessible and cheaper. Recent studies suggest that the flotation of coarse particles using microbubbles has some advantages. However, a thorough analysis of the effectiveness of various flotation parameters and the impact of their interactions on the recovery of coarse particles in the presence and absence of microbubbles has yet to be fully understood. In the current study, the two-level factorial and Box-Behnken experimental designs were performed to characterize, assess, and optimize the implications of seven numerical (sodium oleate, collector; calcium oxide, activator; MIBC, frother; impeller speed; froth depth; pulp concentration; fine particles) and one categorical (microbubbles) independent parameters on the coarse quartz particles. Characterization revealed that froth depth did not significantly affect the flotation recovery of coarse particles in the mechanical laboratory cell. The effects of the variables in the presence of microbubbles revealed that sodium oleate and impeller speed significantly impacted recovery, followed by calcium oxide and fine particles, both of which had a medium influence, and MIBC and pulp concentration, which had a minimal impact. The recovery of coarse particles increased by 92.714% when microbubbles were used, compared to the estimated maximum recovery under ideal conditions of 62.258% without them. From this, it can be concluded that a high coarse particle flotation recovery is possible by optimizing the hydrodynamic conditions and the chemical environment using microbubbles. [ABSTRACT FROM AUTHOR]

In Turkey, more than 95% of the pistachio (Pistacia vera L.) orchards are not irrigated. Therefore, a 4-year field trial was conducted to determine the effect of Tarımbor fertiliser (containing 18.5% boron [B]) on the yield, quality, and B content of two pistachio cultivars ('Uzun' and 'Siirt') planted under nonirrigated conditions. Tarımbor was applied to the pistachio trees as a soil application (0, 200, 400, and 600 g/tree) and a foliar spray (0%, 0.1%, 0.2%, and 0.3% w/v, using a tractor-mounted sprayer at the 'early bud break' stage and the 'fully leafed out' stage). Both the soil and foliar applications of Tarımbor had a significant effect on the pistachio yield, quality, and B content compared with the control. However, the foliar application resulted in greater improvements in the B content of leaves in both cultivars and the split nut ratio and kernel ratio in 'Uzun'. The greatest increases in yield were observed for the 0.3% foliar application for 'Uzun' (30%) and the 200 g/tree soil application for 'Siirt' (59%). In terms of quality, the application of Tarımbor appeared to have a greater effect on 'Uzun' than on 'Siirt'. No vegetative symptoms of B toxicity were observed in either cultivar when high concentrations of B were applied. Thus, Tarımbor could be used effectively as a foliar spray to enhance the B levels in the leaves of pistachio trees grown under nonirrigated conditions. [ABSTRACT FROM AUTHOR]

Abstract: In this study, optimization of some parameters of stirred mill on ultra-fine grinding of refractory Au/Ag ores was performed. A three-level Box–Behnken design combining a response surface methodology (RSM) with quadratic programming (QP) was employed for modelling and optimization of some operating parameters in ultra-fine grinding. Grinding tests were carried out in a laboratory scale pin-type vertical stirred mill. The relationship between the response, i.e. d80 size, and four grinding parameters, i.e. ball diameter, grinding time, ball charge ratio and stirrer revolution was presented as empirical model equations. Analysis of variance showed a high coefficient of determination value (R2 =0.9698), thus ensuring a satisfactory of the second-order regression model with the experimental data. The model equations were then optimized using the quadratic programming method to minimize for d80 size within the experimental range studied. The optimum conditions were found to be 1.61mm for ball diameter, 11.50min for grinding time, 80% for ball charge ratio and 745rpm for stirrer revolution for this grinding process. In order to verify the improvement of grinding performance using the optimal level of control factors three verification experiments were conducted, and the results for d80 was 3.37μm, which were smaller than those obtained in the initial tests. [Copyright &y& Elsevier]

Abstract: The multi-gravity separator (MGS) is one of the fine particle mineral concentration machines based on gravity separation. Concentration performance, indicators such as grade and recovery, depends on appropriate selection of process parameters. Maximum concentrate grade and maximum recovery is of today’s demand with MGS concentration as it is with many concentration processes. To date, no experimental study on MGS has been done for grade and recovery simultaneously. In this paper, the multi-objective optimization of grade and recovery using the Taguchi quality loss function has been carried out for chromite concentration with MGS. The input process parameters considered are drum speed, tilt angle, wash water flow rate, and shake amplitude. The results show considerable improvement in both the quality characteristics such as grade and recovery with multi-objective optimization, compared to the initial value of grade and recovery. [Copyright &y& Elsevier]

In this study, the interpretation of float–sink test data by simple equations on coals of different origins with respect to sulfur content has been investigated. Primarily, the cumulative weight and sulfur content of the floating fraction have been determined for each coal in all relative densities tested. For deriving of the equations, the recoveries of both non-sulfur and sulfur compounds in cumulative floating part have been calculated. Then, the relationship between the recoveries and relative densities has been stated as simple equations and the calculated values from equations have been compared with the experimental results. Furthermore, it has been found that these types of equations are suitable for the interpolation of sink–float data. The results reveal that the float–sink test results can be stated by simple equations relating to the sulfur content. [Copyright &y& Elsevier]