The Effect of Leachate on the Compacted and Consolidated Clay Soils

Solid waste landfills constitute a potential major threat to groundwater quality. Water present in the waste, rainwater infiltration during and/or after the landfilling process and groundwater penetration can result in the generation of leachate. Leachate is a kind of waste liquid consisting of waste contaminants. Clay soils are natural matters to minimize the permeability of natural soil liners in landfill areas. Some contaminants in the leachate can alter compacted clay soils and cause increasing or decreasing permeability. This study investigates effects of leachate on the permeability of the compacted and consolidated clay soils, thereby evaluating the effectiveness of these clay soils as liners in preventing groundwater contamination. To determine removal capability of compacted and consolidated clay soils, some metal ions (Fe(II), Mn(II)) are also measured in influent and effluent of the lab-scale reactor. According to results of this study, Fe(II) and Mn(II) removal efficiency increases with time. Fe(OH)3 and MnO2 precipitations on the clay soil particles increase oxidation rate depending on the autocatalytic effect. Also, in the beginning, some decrease has been observed in the compacted and consolidated clay soils permeability associated with the contamination. However, as time goes by, these results show that leachates may cause an increase in the permeability

Synthesis, characterization and biological assessment of a novel hydrazone as potential anticancer agent and enzyme inhibitor

Noma, Samir Abbas Ali ( Aksaray, Yazar ) Erzengin, Mahmut ( Aksaray, Yazar )In present work, a novel hydrazone compound, namely 1-(5-bromo-2,3-dimethoxybenzylidene)-2-(pyridine-2-yl) hydrazine (5Br2DM2PH), was synthesized by condensation reaction in acidic conditions. The structure of this compound was detailed elucidated by 1H NMR, FT-IR, UV/VIS and XRD methods. Antioxidant activity of the 5Br2DM2PH compound was investigated by scavenging activity on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals. The 5Br2DM2PH compound exhibited high scavenging activity compared with reference antioxidant. To determine in vitro cytotoxic effect of its, cell viability was tested using MTT assay on human breast (MCF-7) and colon (Caco-2) cancer cell lines. The results showed that the cytotoxic effect of the 5Br2DM2PH is more potent than cisplatin. The IC50 value for MCF-7 is 16.8 μM while the value for Caco-2 is 11.8 μM. In addition, the in vitro inhibitory property of the compound 5Br2DM2PH was carried out on human paraoxonase-1 (hPON-1) and the IC50 value was found as 13.8 μg. Our ambitions for the novel 5Br2DM2PH compound will guide many future studies in the field of medicine, analytical and drug applications, as well as new organic synthesis

The Toxicity Assessment of Iron Oxide (Fe3O4) Nanoparticles on Physical and Biochemical Quality of Rainbow Trout Spermatozoon

The aim of this study was to evaluate the in vitro effect of different doses (50, 100, 200, 400, and 800 mg/L) of Fe3O4 nanoparticles (NPs) at 4 °C for 24 h on the kinematics of rainbow trout (Oncorhynchus mykiss, Walbaum, 1792) spermatozoon. Firstly, Fe3O4 NPs were prepared at about 30 nm from Iron (III) chloride, Iron (II) chloride, and NH3 via a co-precipitation synthesis technique. Then, the prepared Fe3O4 NPs were characterized by different instrumental techniques for their chemical structure, purity, morphology, surface properties, and thermal behavior. The size, microstructure, and morphology of the prepared Fe3O4 NPs were studied by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) spectroscopy, and scanning electron microscopy (SEM) equipped with an energy-dispersive X-ray spectrometer (EDS). The thermal properties of the Fe3O4 NPs were determined with thermogravimetric analysis (TGA), differential thermal analysis (DTA), and differential scanning calorimeter (DSC) analysis techniques. According to our results, there were statistically significant (p < 0.05) decreases in the velocities of spermatozoon after treatment with 400 mg/L Fe3O4 NPs. The superoxide dismutase (SOD) and catalase (CAT) activities were significant (p < 0.05) decrease after 100 mg/L in after exposure to Fe3O4 NPs in 24 h. As the doses of Fe3O4 NPs increases, the level of malondialdehyde (MDA) and total glutathione (tGSH) significantly (p < 0.05) increased at doses of 400 and 800 mg/L

Investigation of adsorption of landfill-leachate transport in clay soils

Sızıntı suyu çoğu katı atık depolama alanlarından kaynaklanan inorganik ve organik kompleks karışımını içeren sulu çözeltilerdir. Türkiye’de katı atıklar öncelikli olarak düzenli depolama sahalarında toplanmaktadır. Düzenli depolama alanları sızıntı yaparak yeraltı suyu ve toprağa potansiyel kirlilik kaynağı oluşturmaktadır. Sıkıştırılmış killer veya yerel topraklar ile kil karışımı sıklıkla çok düşük hidrolik iletkenlik bariyerleri elde etmek ve yüzey altı kirlenmeyi önlemek için kullanılır. Bu çalışmada, kesikli sistem ile bazı metal iyonları (Mn, Cu, Fe, Pb, Zn) ile kilin adsorpsiyon kapasitesini belirlemek için deneyler gerçekleştirilmiştir. Bu amaçla, sızıntı suyu ve kil İstanbul'un Asya yakasındaki Şile-Kömürcüoda Depolama Sahası'ndan alınmıştır. Sızıntı suyu ile en etkili adsorban miktarını belirlemek için bir dizi deney gerçekleştirilmiştir. İlk aşamada, sabit miktarda sızıntı suyu ile çeşitli miktarlarda kil kullanılarak optimum kil miktarı belirlenmiştir. Aynı miktarda sızıntı suyu, temas süresinin etkisini belirlemek için çalkalayıcıda optimum kil miktarı ile temas ettirilmiştir. Son adımda, sıcaklığın etkisini belirlemek için tüm deneyler üç farklı sıcaklıkta gerçekleştirilmiştir. Çalışmanın sonunda, tüm deneylerin ardından kilin optimum miktarı 0.25 gr bulunmuştur. Bu sonuca bağlı olarak Mn, Cu, Fe, Pb, Zn iyonları için optimum sıcaklık 35°C bulunmuş ve geri kazanım veriminde % 99'a kadar ulaşılmıştır.Leachates contained in most modern waste- containment facilities are aqueous solutions containing a complex mixture of inorganic and organic species. In the Turkey, solid wastes are primarily disposed in landfills. Landfills may potentially leak leading to contamination of underlying soils and groundwater. Compacted clays or mixtures of local soils with clay are frequently used to achieve very low hydraulic conductivity barriers and prevent subsurface contamination. In this study, experiments have been carried out to determine the adsorption capacity of the clay soils for some metal ions (Mn, Cu, Fe, Pb, Zn) in a batch reactor systems. For this purpose the leachate and clay soils was taken from Şile- Kömürcüoda Landfill Area on the Asian side of Istanbul. A series of experiments were carried out to determine the most efficient adsorbent amount with the leachate. In first step, the optimum amount of clay was determined by using clay in various amounts with constant amount of the leachate. In second step, the same amount of leachate was contacted with the optimum amount of clay in shaker to determine the effect of contact time. In last step, in order to determine the effect of temperature, all experiments were carried out at three different temperatures. In this study, after all experiments, the optimum amount of the clay was found 0.25 g. Depending on this result, optimum temperature was found 35 0C and recovery efficiencies up to 99 percent were achieved for Mn, Cu, Fe, Pb, Zn ions

Aliphatic Polyurethane Films Based on Hexamethylene Diisocyanate and Saccharides for Biocompatible Transparent Coating on Optic Medical Devices

Polyurethanes are widely used in daily life, from the textile industry to medical applications. In this study, a biocompatible and transparent coating from polyethylene glycol-based polyurethanes including different type of saccharide (xylose as monosaccharide, sucrose as disaccharide, or starch as polysaccharide) is prepared. Prepared optically transparent polyurethanes are characterized with different instrumental analysis techniques and contact-angle measurements. Thermogravimetric analysis data allow understanding that the synthesized saccharide based polyurethanes are resistant to high temperatures, which means that medical devices can be easily coated with one of the saccharide-based polymers during the manufacturing process. The study results also show that synthesized polyurethane samples having a different kind of saccharides present high biocompatibility and transparency properties via In vitro cytotoxicity analysis and optic transparency tests. For xylose, sucrose, or starch containing polyurethanes, the tranmittance values are 97.72%, 85.20%, and 89.23%, respectively. In addition, scanning electron microscope images show that the samples also have smooth surfaces which can be used for proper coating of medical devices. Consequently, this manuscript addresses synthesis and characterization of the optically transparent polyurethanes based on specific saccharides for biocompatible and transparent surfaces especially in optic medical devices such as colonoscopy applications and laparoscopic detection probes.Scientific and Technical Research Council of Turkey (TUBTAK) [111T104]This study was supported by a grant (111T104) to Burhan ATES from The Scientific and Technical Research Council of Turkey (TUBTAK)