Role of microbes,metabolites and effector compounds in host–microbiota interaction: a pharmacological outlook

Environmental Chemistry Letters - Microbial cells react with intestinal surfaces and produce enzymes and metabolites that influence human health, host metabolism and immunity. Gut...     

Effect of agrochemicals on earthworms

This review describes the toxic effects of agrochemicals on earthworms. Carbamates are described as extremely toxic to earthworms in comparison to organophosphorus insecticides. Some pesticides have drastic effect on the nervous system of the earthworm. Earthworm can accumulate heavy metals from the soil in higher levels than any other animal. Mercury is twenty times more toxic than chromium.     

Probing and understanding interaction of Eu(III) with γ- alumina in presenceof malonic acid

Radionuclide migration in aquatic environment is influenced by its sorption onto colloids/mineral oxides and the presence of organic complexing anions. With a view to understand the sorption of trivalent actinides by mineral oxides in presence of organic acid, in the present study, Eu(III), malonic acid (MA) and γ-alumina are considered as representatives of trivalent actinides, low molecular weight natural occurring organic acid and aluminol sites, respectively. The influence of MA on sorption of Eu(III) by γ-alumina was elucidated by batch sorption, spectroscopic techniques and surface complexation modeling, for the first time. Attenuated Total Reflection-Fourier Transform Infrared spectroscopic studies of MA sorbed on γ-alumina revealed the presence of two inner-sphere surface complexes. Batch sorption for binary (alumina-Eu(III)) and ternary (alumina-Eu(III)-MA) systems were investigated as a function of pH, Eu(III) concentration and sequential addition of Eu(III)/MA. The pH edge for Eu(III) sorption shifts to higher pH with increasing Eu(III) concentration. In ternary systems, Eu(III) sorption is significantly enhanced at pH < 4.5. Eu(III) speciation on γ-alumina is independent of addition sequence of Eu(III)/MA. Time resolved fluorescence spectroscopy of Eu(III) sorbed on γ-alumina exhibited two surface species, XOEu²⁺ and (YO)₂Eu⁺. The enhancement in I₆₁₆/I₅₉₂ and lifetime for ternary systems, as compared to binary system, at low pH, indicates the participation of Eu-MA complexes in the formation of surface species in ternary systems. The diffuse layer model has been employed to successfully model the experimental sorption profiles of binary and ternary systems, using code FITEQL 4.0, by considering the surface species identified by spectroscopic techniques.     

Role of magnetite and humic acid in radionuclide migration in the environment

Sorption of ¹³⁷Cs, ⁹⁰Sr, ¹⁵⁴Eu and ¹⁴¹Ce by magnetite has been studied at varying pH (4 to 11) in the presence and absence of humic acid. The sorption studies have also been carried out at varying ionic strength (0.01 to 0.2 M NaClO₄) and humic acid concentration (2 to 20 mg/L). Percentage sorption of ¹³⁷Cs and ⁹⁰Sr was found to be pH dependent, with the sorption increasing with increasing pH of the suspension. At any pH, the percentage sorption of ⁹⁰Sr was higher than that of ¹³⁷Cs. The results have been explained in terms of the electrostatic interaction between the positively charged metal ions and the surface charge of the magnetite which becomes increasingly negative with increasing pH. On the other hand, ¹⁵⁴Eu and ¹⁴¹Ce were found to be strongly sorbed by the magnetite at all pH values, with the sorption being independent of pH. The strong sorption of trivalent and tetravalent metal ions suggests the role of complexation reactions during sorption, apart from the electrostatic interactions. However, in the case of ¹⁴¹Ce surface precipitation of Ce(III) formed by reduction of Ce(IV) in the presence of magnetite cannot be ruled out. Presence of humic acid (2 mg/L) was found to have negligible effect on sorption of all metal ions.     

Growth and properties of hydrothermally derived crystalline ZnSe quantum dots

Environmental Science and Pollution Research - Chalcogenide nanostructures are the materials with diverse applications. Here, we report rapid hydrothermal synthesis of crystalline ZnSe quantum dots...     

Identification of impurities in technical monocrotophos

A number of impurities present in technical monocrotophos (76%) were isolated by column chromatography and structures were assigned by GC‐MS analysis.     

Cold plasma technology: advanced and sustainable approach for wastewater treatment

Environmental Science and Pollution Research - Cold plasma has been a potent energy-efficient and eco-friendly advanced oxidation technology which has gained attention in recent decades as a...