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The development of high-efficiency and durable bifunctional electrocatalysts is an important and challenging topic in the area of energy storage/conversion. Herein, we prepared metallic cobalt nanoparticle decorated N-doped graphitic sheets (Co@NGr) by adopting facile pyrolysis of a mixed ligand cobalt-based MOF (CoMOF-2) as a sacrificial template displaying good OER and HER activity. The catalytic material harvested at three different pyrolytic temperatures was characterized by various analytical methods such as PXRD, SEM, TEM, Raman, and XPS analyses. The catalytic activity of the obtained hybrid composite materials towards oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) was studied. Co@NGr-900 was found to be an efficient bifunctional electrocatalyst and 10 mA cm−2 current density was afforded at an overpotential of 390 mV for OER and 340 mV for HER respectively. This study provides insight for the development of cost-effective nonprecious element-based electrocatalysts for water splitting which has relevance in energy storage and conversion. Catalytic performance is governed by the synergistic compositional effect of metallic cobalt/nitrogen-doping in the graphitic carbon increasing the electrical conductivity/active sites of the composite material.

The effect of co-doping of Zn2+/Zr4+ ions on surface morphology, structure and magnetic properties of BaZnxZrxFe12-2xO19 (x=0.00, 0.20,0.40,0.60,0.80, 1.00) synthesized using Pechini method has been investigated. XRD data reveals that the samples are phase pure and have no intermittent phase. The c/a parameter is 2+/Zr4+ dopant seen using FE-SEM micrographs. The local crystal structure distortion with increasing Zn2+/Zr4+ dopant composition is confirm by Raman measurements. M vs H plots reveal that all the samples shows magnetic ordering. The highest Ms value has been noticed to be 68.43 emu/g in x=0.20 sample. The Hc value varies from 5350 Oe to 763 Oe with increase in dopant concentration. These materials have strong potential in magnetic recording applications.

Sustainable intensification of agricultural productivity is a global challenge. The sap of the commercially important red seaweed, Kappaphycus alvarezii, has been of interest in this regard, and its application as foliar spray has had a profound impact on the yields of many crops. It has been shown to contain indole acetic acid, kinetin, zeatin and gibberellic acid (GA3) but no study is yet reported on the interactions among these constituents, if any. In the present study, selective solvent extraction was undertaken to obtain GA3-free and indole acetic acid-free sap compositions. Another composition was prepared by autoclaving the sap which resulted in degradation of all the above growth hormones. The sap variants, along with water spray (control) and pristine sap, were applied on Zea mays as foliar spray over three consecutive seasons in dilute form. The four sap treatments were at par with one another—and significantly superior to control treatment—in so far as grain yield and quality were concerned. Pristine sap was subsequently shown to also contain choline and glycine betaine, and these were detected in similar amounts in all the sap variants, apparently indicating their profound influence on grain yield. Another important observation was that GA3-free sap led to heightened photosynthetic activity which translated into 26 % increase in corn stover yield compared to pristine sap. This is hypothesized to be on account of prevention of negative interactions between GA3 and other hormones. The study constitutes the first report of enhancement of performance of a natural seaweed plant stimulant towards increasing plant growth through simplification of its composition.

This work evaluates cationic intercalation of Capecitabine (Xeloda), an antineoplastic agent in interlayer gallery of Na + -MMT, which was further compounded with Poly ( L -Lactide) to form microcomposite spheres, for oral chemotherapy of breast cancer. The XRD, TGA, SEM, TEM and FT-IR analysis indicated the CAP intercalated in interlayer of MMT and stabilized in the longitudinal monolayer mode by electrostatic interface. No significant alteration in fundamental active properties of CAP was found in the MMT efficacy and data from in vitro study showed controlled drug release pattern >72 h. The efficacy of CAP-MMT hybrid/MPs was also confirmed on Human neuroblastoma cell line (IMR32) by in vitro cell culture experiments evaluating cell cytotoxic and oxidative stress marker indices which showed that intercalated drug and MPs, were as effective as pristine drug. In vivo pharmacokinetics of CAP-MMT hybrids in rats was examined and plasma CAP levels were evaluated. Our findings suggest that CAP-MMT hybrids and MPs can be of considerable value in chemotherapy of malignant neoplastic disease with reduced side effects and clearly demonstrated that MMT not only plays a role as a delivery matrix for drug but also facilitates significant increase in the delivery proficiency.

Preparation of a high flux poly(dimethylsiloxane) (PDMS) membrane for separation of organics from water by pervaporation has been a challenging task. For this, the membrane should be as thin as possible since the productivity flux is inversely proportional to the membrane thickness. In an attempt to understand the relationship between the membrane structure and flux, the membranes of different thickness varying from about 0.2 to 150 μm were prepared and studied. The neat PDMS membrane prepared by evaporation casting of the 10% (w/w) polymer solution in n-hexane has an average thickness of 150 μm while a porous support was used for preparing the thinner membranes. ATR-IR, SEM, DSC, XRD and Contact angle measurements showed that the thinner membrane had relatively more crystalline domains and less hydrophobic. The nanostructure of the membranes was investigated using small angle neutron scattering (SANS) measurements. While the SANS data of the neat membrane was fitted well with Debye model of polymer chain, the data of coated membranes was fitted with a combination of Debye chain model and some aggregated structure of polymer chains. Among the coated PDMS films, the thinly coated film exhibited relatively a higher amount of the chain aggregates. This might imply that the thinner membrane had a relatively loose structure responsible for low selectivity but high flux in the separation of organic from water by pervaporation.

The composite membranes capable of recognizing enantiomers of lysine monohydrochloride were prepared by interfacial polymerization of l -lysine and piperazine with trimesoyl chloride in situ on the surface of polysulfone membrane. The chemistry and thickness of selective layer determined by variable angle ATR–FTIR spectroscopy and the morphology of membranes examined by scanning electron microscope to understand and correlate with performance of membrane. Pure enantiomers were separated from aqueous solution of racemic lysine monohydrochloride at low pressures in membrane testing module to determine the performance of membranes for optical resolution. The effect of composition of solutions used to prepare chiral selective layer on the performance of membranes was determined. The effects of separation process parameters such as trans-membrane pressure, permeation time and concentration of feed solution on flux and separation were also determined. The membranes indicated preferential permeability for d -lysine monohydrochloride by enriching permeates up to 90% enantiomeric excess. The membrane prepared using l -lysine and piperazine monomers in equal proportion (W/W) exhibited highest enantiomeric excess (90%). The trans-membrane pressure and concentration of feed solution indicated remarkable effect on enantioselective permeability of membranes. Highest enantiomeric excess and flux obtained with dilute feed solution at 172 kPa.