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Heavy metals like copper and nickel are highly toxic due to their non-biodegradable and carcinogenic nature. In this study, adsorption technique was used to remove these undesired heavy metals from aqueous solutions. Carbon nanotubes (CNTs) due to fascinating member in carbon family are selected as an adsorbent which was further functionalized by citric acid and sulfuric acid. The morphological and structural properties of CNTs before and after functionalization were studied by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM) and energy-dispersive X-ray (EDX) spectroscopy. Batch adsorption method was applied to investigate the adsorption of Cu2+ and Ni2+ ions on bare and acid-functionalized CNTs. The equilibrium concentration of Cu2+ and Ni2+ ions was determined by atomic absorbance spectroscopy. The respective maximum adsorption capacity for Cu2+ ions by CNTs, SA-CNTs and CA-CNTs was 13.19, 25 and 65.35 mg/g, whereas for Ni2+ ions these were 14, 33 and 40 mg/g. The thermodynamic parameters like ΔH, ΔS and ΔG were also calculated by using van't Hoff equation. The adsorption data was compared with the previous findings, and the results showed that acid-functionalized CNTs are more effective than bare CNTs for the adsorption of Cu2+ and Ni2+. Finally, the adsorbent recovery was ensured by desorption study of metal ions by using pre-sorbed Cu2+ and Ni2+ ions. [ABSTRACT FROM AUTHOR]

Phosphorylation reactions of glycerol were studied using different inorganic phosphates such as sodium phosphate, trimetaphosphate (a condensed phosphate), and struvite. The reactions were carried out in two non-aqueous solvents: formamide and a eutectic solvent consisting of choline-chloride and glycerol in a ratio of 1:2.5. The glycerol reacted in formamide and in the eutectic solvent with phosphate to yield its phosphorylated derivatives in the presence of silicates such as quartz sand and kaolinite clay. The reactions were carried out by heating glycerol with a phosphate source at 85 °C for one week and were analyzed by 31P-nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS). The yield of the phosphorylated glycerol was improved by the presence of silicates, and reached 90% in some experiments. Our findings further support the proposal that non-aqueous solvents are advantageous for the prebiotic synthesis of biomolecules, and suggest that silicates may have aided in the formation of organophosphates on the prebiotic earth.

The second-order non-linear optical (NLO) response of organoimido-substituted hexamolybdates has been tuned from 218.61 × 10-30to 490.10 × 10-30esu. The dipole polarizabilities and second-order nonlinear optical (NLO) properties of organoimido derivatives of hexamolybdates have been investigated by using the time-dependent density functional response theory (TDDFT). The electron withdrawing ability of F (fluorine) has played an important role in tuning the second-order NLO response in this class of organic-inorganic hybrid compounds; particularly system 6 [Mo6O18(NC16H8F2(CF3)2I)]2–with the static second-order polarizability (βvec) computed to be 490.10 × 10-30esu. Thus, our studied systems have the feasibility to be excellent tuneable second-order NLO materials. The analysis of the major contributions to the βvecvalue suggests that the charge transfer (CT) from POM to organic ligand (D-A) along the z-axis has been enhanced with addition of F atoms at the end phenyl ring which directs head (POM) to tail (fluorinated ring) charge transfer. The computed βvecvalues have been tuned by incorporation of different halogen atoms at the end phenyl ring of organoimido segment. Furthermore, substitution of two trifluoromethyl (–CF3) groups sideways along with iodine (I) at the terminus of end phenyl ring in the organoimido ligand has a striking influence on tuning the optical non-linearity, as CT from POM to the organoimido ligand was significantly increased. These systematic small changes in molecular composition by substitution of different halogen groups leads to a tuning the NLO response; the so-called ‘ripple effect' catches this point nicely. Thus, the present investigation provides thought provoking insight into the tuneable NLO properties of organoimido-substituted hexamolybdates. [ABSTRACT FROM AUTHOR]

The poor reactivity of insoluble phosphates, such as apatite-group minerals, has been a long-appreciated obstacle for proposed models of prebiotic organophosphate formation. This obstacle presents a significant challenge to the nascent development of an RNA world and other models for the origins of life on Earth. Herein, we demonstrate that a scenario based on the formation of a urea/ammonium formate/water (UAFW) eutectic solution leads to an increase in phosphorylation when compared to urea alone for phosphate sources of varying solubility. In addition, under evaporative conditions and in the presence of MgSO 4 , the UAFW eutectic mobilizes the phosphate sequestered in water-insoluble hydroxyapatite, giving rise to a marked increase in phosphorylation. These results suggest that the prebiotic concentrations of urea in a geologically plausible evaporitic environment could solve the problem of organic phosphorylation on a prebiotic Earth., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)