Issue 3 - [November]

(E)-2-((pyren-1-ylmethylene)amino)phenol (3) containing pyrene linked through an imine bond to a phenol unit was synthesized and its Fe-complex 4 was prepared. The complex 4 is characterized by infrared (IR), x-ray diffraction (XRD) and UV-Vis spectroscopy techniques. The synthesized complex was used as a sensitizer in a solar cell structure. From the current density (J) - voltage (V) curve obtained, the values of the short-circuit current density (JSC), maximum current density (JM), open-circuit voltage (VOC) and maximum voltage (VM) for the complex 4 were determined as 6.68 mA /cm2, 4.73 mA /cm2, 0.56 V and 0.41 V, respectively. Using these parameters, the fill factor (FF) and power conversion efficiency value (η) of complex 4 were calculated as 0.52 and 1.94, respectively. This value shows that complex 4 can be used as an effective sensitiser in solar cell applications.

Direct discharge of black water (BW) without treatment to the natural environment causes problems for the environment. The present research aimed to examine the impact of direct disposal of BW on the municipal wastewater (MWW) and surrounded soil characteristics in the BW disposal site in Erbil City- Kurdistan Region (KR), Iraq. To check the effect of BW on the boarded MWW and the soil; BW, MWW, BW mixed with MWW (BWMWW), polluted soil, and clean soil samples were collected and analyzed. Samples of BW, MWW, and BWMWW were tested for 32 physical-chemical and biological quality parameters such as pH, turbidity, solids, color, dissolved oxygen, five day biochemical oxygen demand (BOD5), chemical oxygen demand (COD), ammonia, oxidation-reduction potential (ORP), sulphate, oil and grease, phosphate, Most probable number (M.P.N.) of coliform, Thermo tolerant, M.P.N. E.Coli …etc. In contrast, soil samples were tested for 37 parameters, for instance pH, ORP, organic matter (OM), sulfite, Titanium, Vanadium, Chromium, Manganese, Iron, Cobalt, Nickel, Copper, Zinc, Gallium, Arsenic, Rubidium, Strontium, Yttrium, Zirconium, Molybdenum, Silver, Cadmium, Mercury, Lead, Thorium and Uranium. Results revealed that the direct disposal of BW without treatment commonly affected on the MWW and the surrounded soil characteristics. Potential treatment processes and solutions for BW disposal were presented.

Silver nanoparticles (GSNPs) were synthesized from extracellular metabolites of endophytic isolates of Fusarium verticillioides (KT587649) to evaluate their efficiency as new biosorbent agents for the exclusion of cadmium Cd (II) from aquatic systems. The GSNPs were characterized through X-ray diffraction (XRD) and transmission electron microscopy (TEM). Results show that the most efficient Cd (II) removal rate by both biosorbents was at pH 7.0. The optimal contact times were 30 and 40 min by F. verticillioides and GSNPs, respectively. Langmuir adsorption isotherms revealed that the highest calculated adsorption capacities of F. verticillioides and GSNPs for Cd (II) were 185±0.25 mg/g and 176±0.18 mg/g, respectively. The harmonized adsorption isotherms (between the Freundlich isotherm and Langmuir models) indicated a high correlation coefficient (r2 > 0.97). The kinetics of the biosorption process fitted well with the pseudo-second-order kinetic model. This study has thus confirmed the biosorbent capacity of F. verticillioides and its GSNPs for the exclusion of Cd (II) from any contaminated aquatic system and shows it is an eco-friendly method with great feasibility and potential to convey economic and other benefits in wastewater treatment technologies

The present study was carried out to understand the hydrological behavior of natural springs/streams in Semalta watershed, Kalsi block, Dehradun. The surface catchment areas of springs/streams were delineated using Survey of India Toposheet (1:50,000 scale) whereas drainage, slope, and land use maps of the watershed were prepared using open source ILWIS GIS software. The drainage map of the watershed indicated the ephemeral, intermittent and perennial nature of streams and the slope map of the watershed indicated that the majority of the area falls under scrubland. The discharge trend at different gauging sites from October 2015 to March 2016 indicated that the flow rate of the stream gradually decreased from post-monsoon to pre-monsoon period. The geohydrological and geomorphological study indicated that most of the springs/streamflow were controlled by fracture/joints with slate/phyllite/limestone/quartzite as country rock. The pH of most of the stream water was mildly alkaline (7.85-8.82) whereas EC was non-saline (0.087-0.425) and temperature varied from 14-23°C. Results on major ions indicated that a higher percentage of NH4+ together with NO3- was possible because of anthropogenic influence. In addition, the higher percentage of SO4- and F- was due to lithological pyrite whereas the higher percentage of HCO3- was due to pyrite weathering of slate. Results on the isotopic variation of δ18O showed that samples were collected with a total height difference of 700 m with a variation of -0.21‰ per 100 m for stream water and -0.5‰ for rainwater. On higher altitudes mainly narrow subsurface pathways are found and therefore only small size of structures are required for recharging and vice versa for the recharge of springs located in lower altitudes. The present study discusses various sampling techniques to ascertain the altitude of recharge of springs which would form the basis for taking appropriate on field activities for spring/stream rejuvenation.