Flowsheet assessment and capacity evaluation of an iron ore processing plant by simulation

Ispitivao se i simulirao pogon za obradu željezne rudače u Sivasu (Turska) na temelju stvarnih i eksperimentalnih rezultata. Primijenjen je AggFlow™ simulacijski program, a prema potrebi koristili su se eksperimentalni rezultati dobiveni u laboratorijima za obradu metala Dokuz Eylül Univerziteta. Rezultati dobiveni AggFlow™ programom usporedili su se s eksperimentalnim i stvarnim podacima. Kombinirali su se postojeći podaci pogona, eksperimentalni rezultati i oni dobiveni simulacijskim programom kako bi se dobio optimalni projekt pogona s proračunom konačnih rezultata. Simulacija nije pomogla samo kod odabira strojeva i opreme već je istaknula neke ekonomske aspekte prije montiranja pogona. Pokazala se važnost simulacije jer bi tako vlasnici kompanije postali svjesni količine ulaganja kapitala, proizvodnih troškova i potrebnih strojeva, a što je najvažnije, količine koncentrata koja se može proizvesti raznim alternativama i primjenama.An iron ore processing plant in Sivas (Turkey) was investigated and simulated depending on real and experimental data in this study. The AggFlow™ simulation packaged program was used and the experimental results conducted in mineral processing laboratories of Dokuz Eylül University were applied to the simulation when necessary. The results gathered by AggFlow were crosschecked with experimental and real data. The former plant design observations, experimental results and simulation software were combined to present an optimum plant design by calculating the final concentrate outputs. Hence, the simulation not only helped in machinery and equipment selection, but also put forth some economic aspects before the assembly of the plant. The importance of simulation was revealed since the company owners would be aware of the amount of capital investment, production costs, and the machinery to be ordered and most importantly, the amount of concentrate to be produced with different alternatives and applications

Fibrin sealant as a carrier for sustained delivery of antibiotics

Objective: To evaluate the activity and sustained release of antibiotics from fibrin sealant against common strains of ocular bacteria. Methods: Vancomycin, ceftazidime, moxifloxacin and lomefloxacin were incorporated into fibrin sealant in the shape of discs. Each antibiotic disc and control fibrin disc without drug was tested in vitro against standard bacterial strains of Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pneumoniae and Pseudomonas aeroginosa. After 24 hours of incubation at 37 °C, the discs were transferred to new plates of bacteria and triplicated for each antibiotic. Results: All antibiotic discs demonstrated detectable activity after 24 hours. Vancomycin had the longest duration of activity (4 days) on the S. pneumonia grown plate. The moxifloxacin discs showed a prolonged inhibition of S. aureus and S. pneumonia for 3 days and inhibited the other strains for 2 days. Conclusion: Fibrin sealants provided prolonged drug delivery, which indicates that antibiotic-loaded fibrin clots could be useful for early ocular postoperative care and treatment. J Clin Exp Invest 2014; 5 (2): 194-19

Quercetin protects the retina by reducing apoptosis due to ischemia-reperfusion injury in a rat model

Purpose: This study aimed to investigate the effect of quercetin on apoptotic cell death induced by ischemia-reperfusion (I/R) injury in the rat retina. Methods: Twenty-four rats were divided into four equal groups: control, ischemic, solvent, and quercetin. I/R injury was achieved by elevating the intraocular pressure above the perfusion pressure. Intraperitoneal injections of 20 mg/kg of quercetin and dimethyl sulfoxide (DMSO) were performed in the quercetin and solvent groups, respectively, immediately prior to I/R injury, and the researchers allowed for the retinas to be reperfused. Forty-eight hours after injury, the thicknesses of the retinal ganglion cell layer (RGCL), inner nuclear layer (INL), inner plexiform layer (IPL), outer plexiform layer (OPL), and outer nuclear layer (ONL) were measured in all groups. Moreover, the numbers of terminal deoxynucleotidyl transferase dUTP nick-end-labeled [TUNEL (+)] cells and caspase-3 (+) cells in both INL and ONL were evaluated in all groups. Results: The administration of quercetin was found to reduce the thinning of all retinal layers. The mean thickness of INL in the quercetin and ischemic groups was 21 ± 5.6 µm and 16 ± 6.4 µm, respectively (P<0.05). Similarly, the mean thickness of ONL in the quercetin and ischemic groups was 50 ± 12.8 µm and 40 ± 8.7 µm, respectively (P<0.05). The antiapoptotic effect of quercetin in terms of reducing the numbers of both TUNEL (+) cells and caspase-3 (+) cells was significant in INL. The mean number of TUNEL (+) cells in INL in the ischemic and quercetin groups was 476.8 ± 45.6/mm2 and 238.72 ± 251/mm2, respectively (P<0.005). The mean number of caspase-3 (+) cells in INL of ischemic and quercetin groups was 633.6 ± 38.7/mm2 and 342.4 ± 36.1/mm2, respectively (P<0.001). Conclusion: The use of quercetin may be beneficial in the treatment of retinal I/R injury because of its antiapoptotic effect on the retinal layers, particularly in INL

Protective Effect of Hesperetin and Naringenin against Apoptosis in Ischemia/Reperfusion-Induced Retinal Injury in Rats

Purpose. Hesperetin and naringenin are naturally common flavonoids reported to have antioxidative effects. This study was performed to investigate whether either hesperetin or naringenin has a protective effect against apoptosis on retinal ischemia/reperfusion (I/R) injury. Methods. Retinal I/R was induced by increasing the intraocular pressure to 150 mmHg for 60 minutes. Thirty-three male Wistar albino rats were randomised into 5 groups named control, I/R + sham, I/R + solvent (DMSO), I/R + hesperetin, and I/R + naringenin. Animals were given either hesperetin, naringenin, or the solvent intraperitoneally immediately following reperfusion. Thickness of retinal layers and retinal cell apoptosis were detected by histological analysis, tunel assay, and immunohistochemistry assay. Results. Hesperetin and naringenin attenuated the I/R-induced apoptosis of retinal cells in the inner and outer nuclear cells of the rat retina. Retinal layer thickness of the naringenin treatment group was significantly thicker than that of the hesperetin, sham, and solvent groups (P<0.05). Conclusions. Hesperetin and naringenin can prevent harmful effects induced by I/R injury in the rat retina by inhibiting apoptosis of retinal cells, which suggests that those flavanones have a therapeutic potential for the protection of ocular ischemic diseases

Evaluation of intraocular pressure and retinal nerve fiber layer thickness in patients with Helicobacter pylori

Objectives: High prevalence of Helicobacter pylori (HP) in the glaucoma patients was shown in recent studies. In our prospective study we aimed to compare the intraocular pressure (IOP) and the retinal nerve fiber layer thickness (RNFLT) in patients with HP positive and negative. Methods: In 91 patients with gastritis HP was investigated by urea breath test (UBT) and biopsy sample culture Following the full ophthalmologic examination the patients’ IOP was measured by Goldmann applanation tonometry and RNFLT was measured by spectral optic coherence tomography. The patients' demographic and clinical characteristics were compared with the χ² test for categorical variables and with the Mann Whitney U test for continuous variables. Results: Of the 90 patients who meet the including criteria, HP was detected in 74 patients (27 male, 47 female) positive, and in 16 patients (7 male, 9 female) negative. Median (minimum-maximum) age values were 46 (18-79) in HP positive group and 51 (18-67) in HP negative group. One hundred forty seven eyes in 74 HP positive patients and 31 eyes in 16 HP negative patients included in the study. Median IOP values were determined 14 (7-21) mmHg in HP positive group and 14 (8-18) mmHg in HP negative group. The measurements of RNFLT in superior, temporal, inferior and nasal quadrants found to be respectively 122(98-165), 68(50-101), 135(93-188), 79(51-120) micron in HP positive group and 120(94-161), 67(43-104), 129(94-166), 76(50-97) micron in HP negative group. No statistically significant difference was found when compared IOP and RNFLT measurements between the two groups (p<0.05). Conclusion: In this study found that the IOP and RNFLT measurements of HP positive group was not show statistically significant difference compared with HP negative group. In a large case series, randomized, case-controlled, histologic and serologic studies should be done to show the relationship between HP and glaucoma

Global wealth disparities drive adherence to COVID-safe pathways in head and neck cancer surgery

Peer reviewe

Autogenous Tumbling Media Assessment to Clean Weathered Surfaces of Waste-Rock Particles from a Basalt Quarry

In this study, the optimum feed composition in autogenous tumbling of basalt waste-rock particles to clean their weathered surface was determined. The weathered surfaces of basalt are generally cut out consequent to extraction of basalt columns in quarry operations. The inefficiently cut out portions of basalt cause formation of huge quarry waste dumps causing visual pollution on roadsides. Mixtures of different particle size fractions of basalt waste-rock particles were experimented to achieve the optimum feed material composition. The minimum loss of commercially available basalt particles and maximum clear surface was intended. The results were compared with respect to weight loss (%) and reflectance values of used and generated samples

Impact of process parameters on drying of dolomite ore by microwave energy

Microwave drying tests on dolomite ore were carried out in order to determine the effect of process parameters and variables on its drying mechanism. Dolomite ore was crushed under 2 mm particle size with water to bring the moisture content to about 5% and then was fed into a microwave oven. The time-dependent moisture removal rate and surface temperature changes were determined at different microwave oven powers (180, 600 and 800W). The very low capacities of industrial microwave ovens are a handicap for activities requiring high capacities such as mining. The rate of moisture removal was taken into consideration in evaluating the results. The optimum experimental conditions for drying were carried out at 800W for 8 minutes. This results in the removal of 33% of the moisture from the dolomite ore

Efemçukuru altın cevherinin flotasyon yöntemi ile zenginleştirilmesinin araştırılması

Bu tez çalışmasının amacı, Efemçukuru altın cevherinin flotasyon yöntemiyle zenginleştirilmesinin araştırılmasıdır. Flotasyon çalışmalarında uygulanan prosedür, bölgedeki altın cevherinin yataklanması ve karakteristik özelliklerine bağlı olarak belirlenmiştir._x000B_Altın cevherinin en yüksek altın verimi ve makul bir altın tenörü ile kazanılması için farklı değişkenler araştırılmıştır. Altın fiyatlarının hızla yükselmesi, altın veriminin arttırılmasını daha önemli hale getirmektedir._x000B_Flotasyon yönteminin yanında, cevherin gravite yöntemiyle zenginleştirilmesi de Knelson konsantratörü kullanılarak araştırılmıştır. Bu iki yöntemin birleştirilmesi, siyanür liçine alternative bir yöntem sunmaktadır._x000B_Elde edilen en uygun flotasyon koşulları ve bu koşulları oluşturan mekanizmalar tartışılmıştır. The aim of this study is to investigate the beneficiation of Efemçukuru gold ore by flotation. The flotation procedure is decided due to the mineralogy and characteristics of the gold ore in the region._x000B_The different variables were studied and analyzed to achieve the highest gold recovery with a reasonable gold grade. The high recovery in gold beneficiation is becoming more important since the gold prices continue to increase._x000B_Knelson concentrator was also studied in detail to observe the recoverability of gold ore by gravity methods. The combination of both methods suggested an alternative processing procedure to cyanide leaching._x000B_In conclusion, the optimum flotation parameters obtained are given and the related mechanisms are discussed in detail