Bioflotation represents one of the growing trends to enhance the selectivity of conventional flotation processes. It utilizes the micro-organisms to replace or to interact with the chemical reagents to increase the ga...Bioflotation represents one of the growing trends to enhance the selectivity of conventional flotation processes. It utilizes the micro-organisms to replace or to interact with the chemical reagents to increase the gap between surface properties of similar minerals and to enhance the separation selectivity. In this work, dolomite-phosphate separation was investigated using amphoteric collector （dodecyl-N-carboxyethyl-N-hyroxyethyl-imidazoline） in presence of bacteria. Two types of bacteria, Corynebacterium- diphtheriae-intermedius （CDI）, and Pseudomonas aeruginosa （PA）, were used. The collector-bacteria interaction was characterized by Fourier transform infra-red （FTIR）, frothing height and Zeta potential. The results show that the collector-bacteria interaction improves the flotation selectivity. Although, the PA positively affects the separation results, the CDI cannot lower the MgO to less than 1%. A phosphate content of 0.7% MgO and 31.77% P205 with a recovery of 68% at pH 11, 3.0 kg/t amphoteric collector, 4× 10^7 cells of PA is obtained.展开更多
The study was conducted for the detection of Listeria monocytogenes bacteria from different sources （CSF and blood） obtained from patients in Pediatric hospital and from food sources like （yogurt, raw vegetables an...The study was conducted for the detection of Listeria monocytogenes bacteria from different sources （CSF and blood） obtained from patients in Pediatric hospital and from food sources like （yogurt, raw vegetables and raw milk, sausage）. Ten isolates were isolated from 150 specimens one of them from CSF and one isolate isolated from blood samples the others isolated from food specimens 6 isolates isolated from sausage and 2 from raw vegetables. Isolates were identified traditionally involved culture methods based on selective enrichment and plating followed by the characterization of Listeria spp. based on colony morphology, sugar fermentation and haemolytic properties, identification by Api listeria was done. Determine the isolates that produce biofilm by tissue culture plate method. The highest biofilm forming strains ofListeria monocytogenes isolates appear in No. （D10, El, E5 and E7） OD reading each of them is （0.13, 0.09, 0.11 and 0.19） respectively, the lowest or poor biofilm forming strains appear in No. （D11, D12, E2, E3, E4 and E6） that optical density （OD） reading are （0.04, 0.03, 0.05, 0.04, 0.05 and 0.03） respectively by comparing with control prepared in well （A12） that stained by crystal violate without putting any isolates and the OD reading is （0.003）. Confirmation by PCR was done only for four isolates that produce biofilm （D10 and El） that obtained from CSF and blood sample and for （E5 and E7） that obtained from food samples.展开更多
文摘Bioflotation represents one of the growing trends to enhance the selectivity of conventional flotation processes. It utilizes the micro-organisms to replace or to interact with the chemical reagents to increase the gap between surface properties of similar minerals and to enhance the separation selectivity. In this work, dolomite-phosphate separation was investigated using amphoteric collector （dodecyl-N-carboxyethyl-N-hyroxyethyl-imidazoline） in presence of bacteria. Two types of bacteria, Corynebacterium- diphtheriae-intermedius （CDI）, and Pseudomonas aeruginosa （PA）, were used. The collector-bacteria interaction was characterized by Fourier transform infra-red （FTIR）, frothing height and Zeta potential. The results show that the collector-bacteria interaction improves the flotation selectivity. Although, the PA positively affects the separation results, the CDI cannot lower the MgO to less than 1%. A phosphate content of 0.7% MgO and 31.77% P205 with a recovery of 68% at pH 11, 3.0 kg/t amphoteric collector, 4× 10^7 cells of PA is obtained.
文摘The study was conducted for the detection of Listeria monocytogenes bacteria from different sources （CSF and blood） obtained from patients in Pediatric hospital and from food sources like （yogurt, raw vegetables and raw milk, sausage）. Ten isolates were isolated from 150 specimens one of them from CSF and one isolate isolated from blood samples the others isolated from food specimens 6 isolates isolated from sausage and 2 from raw vegetables. Isolates were identified traditionally involved culture methods based on selective enrichment and plating followed by the characterization of Listeria spp. based on colony morphology, sugar fermentation and haemolytic properties, identification by Api listeria was done. Determine the isolates that produce biofilm by tissue culture plate method. The highest biofilm forming strains ofListeria monocytogenes isolates appear in No. （D10, El, E5 and E7） OD reading each of them is （0.13, 0.09, 0.11 and 0.19） respectively, the lowest or poor biofilm forming strains appear in No. （D11, D12, E2, E3, E4 and E6） that optical density （OD） reading are （0.04, 0.03, 0.05, 0.04, 0.05 and 0.03） respectively by comparing with control prepared in well （A12） that stained by crystal violate without putting any isolates and the OD reading is （0.003）. Confirmation by PCR was done only for four isolates that produce biofilm （D10 and El） that obtained from CSF and blood sample and for （E5 and E7） that obtained from food samples.
