Heavy metals and major nutrients accumulation pattern in spinach grown in farm and industrial contaminated soils and health risk assessment

A pot experiment was conducted to study heavy metals and major nutrients accumulation pattern and to assess possible health risk for adult male and female human through consumption of spinach grown in farm and industrial contaminated soils. The concentrations of Fe, Mn, Cu, Zn, Cr and Pb in aqueous extracts of leaves and roots were determined by an atomic absorption spectrophotometer (AAS). The present study revealed that spinach grown in both soils accumulated higher amount of Cr, which could pose potential health concern to the local residents. On the contrary, it could be a good source of S, Ca and Mg for adult male and female human. Accumulation of heavy metals and major nutrients in leaves of spinach was in the sequence of Fe > Zn > Cr > Mn > Cu > Pb and K > S > Ca > Mg > P, respectively for industrial contaminated soil, while the order was Fe > Mn > Cr > Zn > Cu > Pb and S > K > Ca > Mg ≥ P, respectively for farm soil. The sequence of Zn, Mn, Ca, K and S accumulation in spinach was leaf > root. But in case of Fe, Cr and P the order of accumulation pattern was reverse. Among the metals, the calculated THQ value for Cr surpassed 1, and the values for male were 2.85 and 6.86 and for female were 4.47 and 10.75 due to consumption of spinach grown in farm and industrial contaminated soils, respectively. The study results inferred that Cr health risk through consumption of spinach is unsafe in industrial contaminated sites; and in both places female is more vulnerable than male

Propagation rate coefficients of styrene and methyl methacrylate in supercritical CO2

Without abstract

Outdoor continuous cultivation of self-settling marine cyanobacterium chroococcidiopsis sp.

Spontaneous settling of certain aggregating microalgae or cyanobacteria could potentially alleviate the energy requirement in biomass harvesting. A locally isolated floc-forming marine cyanobacteria, Chroococcidiopsis sp., was initially grown indoor to study its self-settling efficiency; 97% of the biomass settled spontaneously in 1 h. Later, the strain was grown in outdoor raceway tanks (1 square meter) for 70 d. Every alternative day, 50% of the culture was harvested by self-settling, and the supernatant was recycled back to the tank. Average biomass productivities for the strain was 16.08 g/m2/d. The biomass had an average 2.26% water extractable phycobiliproteins that comprised of both phycocyanin (11.4 mg/g) and phycoerythrin (10.6 mg/g). Since Chroococcidiopsis sp. biomass can be harvested very efficiently, it would reduce the energy and cost of biomass production which are deemed necessary for microalgal animal feed and biofuel applications. Furthermore, its ability to produce high-value pigments will also make it economically very attractive from biorefinery approach. Copyright 2018, Mary Ann Liebert, Inc. 2018.The authors would like to acknowledge the support of Qatar National Research Fund (QNRF, a member of Qatar Foundation) for providing the funding (under grant NPRP8-646-2-272) for this study.Scopu

Enhancing the electrocoagulation process for harvesting marine microalgae (Tetraselmis sp.) using interdigitated electrodes

Marketable value of algal biomass has been increasing in recent years due to its wide range of applications. This study investigates the performance of a novel cylindrical interdigitated electrode array in electrocoagulation for the harvesting of marine microalgae (Tetraselmis sp.). The new electrode array is expected to exert a dielectrophoretic (DEP) force which would assist in the harvesting of the microalgae in the electrocoagulation process. Through numerical investigation, the induction of dielectrophoretic force was confirmed in the new electrode array. In this study, 10 min electrolysis time was found to be sufficient to harvest 82.4% microalgae with 1 cm electrode distance and 50 mA/cm2 current density. Furthermore, decreasing the electrode distance to 0.5 cm increased the algal harvesting efficiency to 96.18%. Energy analysis showed that the proposed electrode array shows 38% lower specific energy consumption than the conventional flat sheet electrode array

Solar Wind Hydration of Itokawa Olivine

No abstract available

Solar Wind Hydration of Itokawa Olivine

No abstract available