Green synthesis,characterization, application and functionality of nitrogen-doped MgO/graphene nanocomposite

Environmental Science and Pollution Research - A facile, feasible, and green synthesis via an electrochemical exfoliation process was applied to synthesize nitrogen-doped MgO/graphene nanocomposite...     

Feasibility of producing sustainable geopolymer composites made of locally available natural pozzolan

Journal of Material Cycles and Waste Management - The feasibility of using locally available natural pozzolanic materials as complete replacement of cement binder to produce sustainable geopolymer...     

Mechanistic aspects of poly(ethylene terephthalate) recycling–toward enabling high quality sustainability decisions in waste management

Environmental Science and Pollution Research - Since plastic waste pollution is a severe environmental concern in modern life, the demand for recycling poly(ethylene terephthalate) (PET) has...     

Bioclimatic passive design strategies of traditional houses in cold climate regions

Environment, Development and Sustainability - Providing indoor thermal comfort is one of the most significant factors in architecture that it is observed in traditional buildings all around the...     

Implications of changing cropping pattern to low water demand plants due to climate change: evidence from Iran

Environment, Development and Sustainability - In this research, 17 implications of changing cropping patterns (CP) to low water demand plants (LWDPs) were identified. Then, the experts were asked...     

Environmental kuznets curve and causal links between environmental degradation and selected socioeconomic indicators in Bangladesh

Environment, Development and Sustainability - This study has investigated the Environmental Kuznets Curve (EKC) hypothesis and focuses on the resource stock of the country in relation to the...     

Semiconductor-mediated photocatalysed degradation of two selected priority organic pollutants,benzidine and 1,2-diphenylhydrazine,in aqueous suspension

The photocatalysed degradation of two selected priority organic pollutants, namely benzidine (1) and 1,2-diphenylhydrazine (DPH, 2) has been investigated in aqueous suspensions of titanium dioxide (TiO2) under a variety of conditions employing a pH-stat technique. The degradation was studied by monitoring the change in substrate concentration of the model compound employing HPLC analysis and the decrease in total organic carbon content, respectively, as a function of irradiation time. The degradation kinetics were studied under different conditions such as reaction pH, substrate and photocatalyst concentration, type of TiO2 photocatalyst and the presence of alternative additives such as H2O2, KBrO3 and (NH4)2S2O8 besides molecular oxygen. The degradation rates and the photonic efficiencies were found to be strongly influenced by the above parameters. Toxicity tests for the irradiated samples of benzidine measuring the luminescence of bacteria Vibrio fischeri after 30 min of incubation were also performed. 4-amino-biphenyl (7) and hydroquinone (13) were identified as intermediate products by GC/MS technique and probable pathways for the formation of the products are proposed.     

Influence of aeration rate and reactor shape on the composting of poultry manure and sawdust

To achieve successful composting, all the biological, chemical, and physical characteristics need to be considered. The investigation of our study was based on various physicochemical properties, i.e., temperature, ammonia concentration, carbon dioxide concentration, pH, electrical conductivity (EC), carbon/nitrogen (C/N) ratio, organic matter (OM) content, moisture content, bacterial population, and seed germination index (GI), during the composting of poultry manure and sawdust for different aeration rates and reactor shapes. Three cylindrical-shaped and three rectangular-shaped pilot-scale 60-L composting reactors were used in this study, with aeration rates of 0.3 (low), 0.6 (medium), and 0.9 (high) L min^?1 kg^?1 DM (dry matter). All parameters were monitored over 21 days of composting. Results showed that the low aeration rate (0.3 L min^?1 kg^?1 DM) corresponded to a higher and longer thermophilic phase than did the high aeration rate (0.9 L min^?1 kg^?1 DM). Ammonia and carbon dioxide volatilization were directly related to the temperature profile of the substrate, with significant differences between the low and high aeration rates during weeks 2 and 3 of composting but no significant difference observed during week 1. At the end of our study, the final values of pH, EC, moisture content, C/N ratio, and organic matter in all compost reactors were lower than those at the start. The growth rates of mesophilic and thermophilic bacteria were directly correlated with mesophilic and thermophilic conditions of the compost. The final GI of the cylindrical reactor with an airflow rate of 0.3 L min^?1 kg^?1 DM was 82.3%, whereas the GIs of the other compost reactors were below 80%. In this study, compost of a cylindrical reactor with a low aeration rate (0.3 L min^?1 kg^?1 DM) was more stable and mature than the other reactors.

Implications: The poultry industry is growing in South Korea, but there are problems associated with the management of poultry manure, and composting is one solution that could be valuable for crops and forage if managed properly. For high-quality composting, the aeration rate in different reactor shapes must be considered. The objective of this study was to investigate various physicochemical properties with different aeration rates and rector shapes. Results showed that aeration rate of 0.3 L min^?1 kg^?1 DM in a cylindrical reactor provides better condition for maturation of compost.     

The digestibility of waste activated sludges.

Laboratory digestion studies using waste activated sludges (WAS) were conducted to compare the digestion performance between anaerobic and aerobic processes. Nine samples of WAS from seven wastewater treatment plants were collected and batch-digested under both anaerobic and aerobic conditions for 30 days at 25 degrees C. The cation content of wastewater (both floc and solution phases) and solution biopolymer (protein and polysaccharide) was measured before and after digestion and compared with volatile solids destruction data. The study revealed that each digestion process was associated with a distinct biopolymer fraction, which accounted for differences in volatile solids reduction under anaerobic and aerobic conditions. The anaerobic digestion data showed strong correlations between soluble protein generation, ammonium production, percent volatile solids reduction, and floc iron (Fe). These data suggest that the amount of volatile solids destroyed by anaerobic digestion depends on the Fe content of floc. In aerobic digestion, polysaccharide accumulated in solution along with calcium and magnesium. For aerobic digestion, correlations between divalent cation release and the production of inorganic nitrogen were found. This implies that divalent cation-bound biopolymer, thought to be lectin-like protein, was the primary organic fraction degraded under aerobic conditions. The results of the study show that the cation content in wastewater is an important indicator of the material that will digest under anaerobic or aerobic conditions and that some of the volatile solids will digest only under either anaerobic or aerobic conditions.     

Antigenotoxic effect of allicin against methyl methanesulphonate induced genotoxic damage

Allicin, one of the sulfur compounds especially thiosulphonates of garlic (Allium sativum), possesses antioxidant and thioldisulphide exchange activity and is also shown to cause a variety of actions potentially useful for human health. In this investigation we determined its antigenotoxic potential using chromosomal aberrations (CAs) and sister chromatid exchanges (SCEs) induced by methyl methanesulphonate (MMS) as genotoxic end points both in the presence as well as absence of rat liver microsomal activation system (S9 mix) in cultured human lymphocytes. We tested the effect of 5, 10 and 20 microM of allicin on the damage exerted by 60 microM of MMS. The levels of CAs and SCEs were lowered suggesting an antigenotoxic role of allicin against genotoxic damage both in the presence as well as absence of metabolic activation.