Improvement of the selection technology of copper-molybdenum concentrate with the use of modified flotoragents

The flotation of copper-molybdenum ores Aktogay deposit of Republic Kazakhstan has been studied, with application new synthesized modified reagents. Selective flotation of copper-molybdenum collective concentrate was carried out according to standard technology with application of modified flotation agent (diesel fuel: oil = 1:1) in comparison with traditional apolar (kerosene) collector. The use of the modified reagent in the processing of copper- molybdenum ore allows increasing the molybdenum content in the molybdenum concentrate by 3,6, and extraction - by 5,7 %

Improvement of the selection technology of copper-molybdenum concentrate with the use of modified flotoragents

The flotation of copper-molybdenum ores Aktogay deposit of Republic Kazakhstan has been studied, with application new synthesized modified reagents. Selective flotation of copper-molybdenum collective concentrate was carried out according to standard technology with application of modified flotation agent (diesel fuel: oil = 1:1) in comparison with traditional apolar (kerosene) collector. The use of the modified reagent in the processing of copper- molybdenum ore allows increasing the molybdenum content in the molybdenum concentrate by 3,6, and extraction - by 5,7 %

Improvement of the technology related gold-containing raw materials with the use of ultramicroheterogeneous flotoreagent

The material composition of the gold-containing tailings of the flotation beneficiation of the Zholymbet ore deposit was studied. It was determined that the samples contain 0,9 g/t of gold, 1,22 g/t of silver. The flotation technologices of technogenic gold-containing raw materials with the use of basic and ultramicroheterogeneous flotation reagents were developed. The content of gold in a draft gold concentrate, in comparison with the basic mode, increases by 2,28 g/t - with 19,56 to 21,84 g/t. The extraction of gold in concentrate increased - by 5,52 % - with 66,07 % to 71,59 %. Thus the consumption of collectors is cut for 50 g/t, with 130 to 80 g/t

Improvement of the technology related gold-containing raw materials with the use of ultramicroheterogeneous flotoreagent

The material composition of the gold-containing tailings of the flotation beneficiation of the Zholymbet ore deposit was studied. It was determined that the samples contain 0,9 g/t of gold, 1,22 g/t of silver. The flotation technologices of technogenic gold-containing raw materials with the use of basic and ultramicroheterogeneous flotation reagents were developed. The content of gold in a draft gold concentrate, in comparison with the basic mode, increases by 2,28 g/t - with 19,56 to 21,84 g/t. The extraction of gold in concentrate increased - by 5,52 % - with 66,07 % to 71,59 %. Thus the consumption of collectors is cut for 50 g/t, with 130 to 80 g/t

Recycling technology for gold-containing tailings with the use of a composite reagent microemulsion

The paper contains the laboratory study results for the flotation processing of gold-containing tailings with the use of the composite reagent (CF). The CF flotation reagent is a microemulsion from a composition of sodium butyl xanthate and reaflot. A gold-containing concentrate was obtained with a gold content of 6,7 g/t with a recovery of 59,71 % in the basic mode. The use of the CF composite flotation reagent increases the gold extraction into the gold-containing concentrate by 3,77 %, as compared with the main collector - sodium butyl xanthate. The consumption of CF flotation reagent is reduced by 20 %

Suppression of High-p_T Neutral Pion Production in Central Pb+Pb Collisions at sqrt{s_NN} = 17.3 GeV Relative to p+C and p+Pb Collisions

Neutral pion transverse momentum spectra were measured in p+C and p+Pb collisions at sqrt{s_NN} = 17.4 GeV at mid-rapidity 2.3 < eta_lab < 3.0 over the range 0.7< p_T < 3.5 GeV/c. The spectra are compared to pi0 spectra measured in Pb+Pb collisions at sqrt{s_NN} = 17.3 GeV in the same experiment. For a wide range of Pb+Pb centralities (N_part < 300) the yield of pi0's with p_T > 2 GeV/c is larger than or consistent with the p+C or p+Pb yields scaled with the number of nucleon-nucleon collisions (N_coll), while for central Pb+Pb collisions with N_part > 350 the pi0 yield is suppressed.Comment: 5 pages, 4 figure

Pion Freeze-Out Time in Pb+Pb Collisions at 158 A GeV/c Studied via pi-/pi+ and K-/K+ Ratios

The effect of the final state Coulomb interaction on particles produced in Pb+Pb collisions at 158 A GeV/c has been investigated in the WA98 experiment through the study of the pi-/pi+ and K-/K+ ratios measured as a function of transverse mass. While the ratio for kaons shows no significant transverse mass dependence, the pi-/pi+ ratio is enhanced at small transverse mass values with an enhancement that increases with centrality. A silicon pad detector located near the target is used to estimate the contribution of hyperon decays to the pi-/pi+ ratio. The comparison of results with predictions of the RQMD model in which the Coulomb interaction has been incorporated allows to place constraints on the time of the pion freeze-out.Comment: 9 pages, 12 figure

Event-by-Event Fluctuations in Particle Multiplicities and Transverse Energy Produced in 158.A GeV Pb+Pb collisions

Event-by-event fluctuations in the multiplicities of charged particles and photons, and the total transverse energy in 158$\cdot A$ GeV Pb+Pb collisions are studied for a wide range of centralities. For narrow centrality bins the multiplicity and transverse energy distributions are found to be near perfect Gaussians. The effect of detector acceptance on the multiplicity fluctuations has been studied and demonstrated to follow statistical considerations. The centrality dependence of the charged particle multiplicity fluctuations in the measured data has been found to agree reasonably well with those obtained from a participant model. However for photons the multiplicity fluctuations has been found to be lower compared to those obtained from a participant model. The multiplicity and transverse energy fluctuations have also been compared to those obtained from the VENUS event generator.Comment: To appear in Physical Review C; changes : more detailed discussion on errors and few figures modifie

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals &lt;1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data