Manganese recovery from secondary resources: a green process for carbothermal reduction and leaching of manganese bearing hazardous waste

During the hydrometallurgical extraction of zinc by electrowinning process, a hazardous solid waste called anode mud is generated. It contains large quantity of manganese oxides (55-80%) and lead dioxide (6-16%). Due to the presence of a large quantity of lead, the anode mud waste is considered hazardous and has to be disposed of in secure landfills, which is costly, wastes available manganese and valuable land resources. For recovery of manganese content of anode mud, a process comprising of carbothermal treatment using low density oil (LDO) followed by sulphuric acid leaching is developed.     

Application of Vitis vinifera Microcapsules on Cotton Fabric: A Potential to Prevent UV-Induced Skin Problems

ABSTRACT

Considering the harmful effect of UV radiation, present study was aimed at developing a UV protective finish for cotton fabric using Vitis vinifera leaves extract. Process parameters of the study were optimized for getting maximum UV protection while maintaining other physical properties of the fabric. Box and Behnken design was used under response surface methodology (RSM) for optimization process. It was found that 3.574% concentration of microcapsules with 2.942% concentration of binder at 120.664°C curing temperature were selected as optimum conditions for application of Vitis vinifera microcapsules on cotton fabric. It can be concluded that application of Vitis vinifera microcapsules on cotton fabric incorporates UV protection properties on cotton fabric, which can helpful to prevent various UV-induced skin problems.     

Antimicrobial properties of natural dyes against Gram-negative bacteria

There is increasing interest in adding value to textiles by the use of natural products. Many of the plants from which natural dyes are obtained are, for example, also known to have medicinal properties. In the current study, the antimicrobial properties of eleven natural dyes against three types of Gram-negative bacteria were studied experimentally. Seven of the dyes showed activity against one or more of the bacteria. The minimum inhibitory concentration for three selected dyes was determined. The results demonstrate that certain dyes are able to reduce microbial growth almost completely in the case of Escherichia coli and Proteus vulgaris . Selected dyes would therefore be valuable for the dyeing of sheets and gowns for hospital use, and on articles which are less suitable for laundering such as mattresses and upholstery. The dyes examined exhibited good wash fastness and the antibacterial effect is therefore likely to be durable.     

Polyacrylonitrile reinforced PVA based‐polymeric networks: Structural,morphological, and mechanical aspects

Various bioengineering and industrial applications demand hard, tough, and mechanically strong polymeric blends. A novel combination of polyvinyl alcohol (PVA) and polyacrylonitrile was used to synthesize semi‐IPNs using redox polymerization method in order to achieve desired property combinations in terms of toughness, generally not found in a single polymeric material. The synthesized end products in the form of polymer matrix were characterized by FTIR spectral analysis in order to confirm the incorporation of PAN into PVA, while the morphological aspects studied by AFM analysis showed fair compatibility between the component polymers exhibiting quite smooth surface and nanosize domains. Microhardness investigations were undertaken using the Vicker's indentation technique and the results were analyzed in terms of strain hardening phenomenon. Increase in surface hardness was observed as a result of variation of PVA content within the gel matrix whereas the presence of acrylonitrile as the second network was found to impart toughness as observed by the tensile strength measurements. POLYM. ENG. SCI., 54:2579–2586, 2014. © 2013 Society of Plastics Engineers     

Knowledge building through optimized classification rule set generation using genetic based elitist multi objective approach

Knowledge building is an important activity taken up by various organizations. The paper exemplifies the creation of a knowledge-centric environment for a non-profit sector such as a higher education. Building knowledge and thereafter using it are important aspects of knowledge-centric environment; this further helps the organization to gain competitive advantage. With the increase in popularity of genetic algorithm (GA), the technique has been used in building efficient classifiers for creating effective rule sets. The paper makes use of multi-objective genetic algorithm for building GA-based efficient classifier because classification rule mining is itself, a multi-objective problem. Knowledge expressed through classification rules help in establishing relationships between attributes that are not visible openly. The study assumes importance as curriculum planning is an important aspect of any academic institution, the knowledge derived in the form of rules residing in the knowledge base help to substantiate proper curriculum development, making a sizeable contribution toward professional growth and advancement of the students. On implementation of the findings, educational organizations will be able to institute themselves as knowledge centric.

     

Radiation‐induced graft copolymerization of α‐methyl styrene and butyl acrylate mixture into polyetheretherketone films

Radiation‐induced graft copolymerization of α‐methyl styrene (AMS), butyl acrylate (BA) monomers, and their mixture was investigated on poly(etheretherketone) films. The graft polymerization was carried out using ethyl methyl ketone as the medium for the copolymerization and the maximum degree of grafting of 27% was achieved. It was observed that the grafting is significantly influenced by the reaction conditions, such as reaction time, preirrradiation dose, monomer concentration, monomer ratio, and the reaction temperature. The degree of grafting increases as the monomer concentration increases up to 30%, beyond which a decrease in the grafting was observed. The degree of grafting showed a maximum at 40% BA content in the monomer mixture. The temperature dependence of the grafting process shows decreasing grafting with the increase in the reaction temperature. The presence of AMS and BA grafts in the film was confirmed by FTIR spectra. The relative change in the PBA/PAMS fraction with respect to the reaction temperature has been found in this study. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Cleaner process for shrink proofing of wool using ultraviolet radiation and sericin

Conventional shrink proofing technologies for wool are based on use of strong chemicals, such as chlorine to enhance surface hydrophilicity, followed by application of a chemical coating to mask the scales. This process, though effective, results in the production of polluted wastewaters containing large quantities of chloro-organic compounds. In the current study, surface modification was carried out using a dry process of irradiating wool with 172 nm radiation, followed by treatment with a reclaimed biopolymer sericin to mask the scales. The paper examines the effect of process parameters, such as the duration of irradiation, pH of bath, and concentration of sericin on area shrinkage. Wool fabrics irradiated for 5 min followed by padding with 5 gpl of sericin at pH 4 showed zero area shrinkage with no loss in strength. Fabric appearance remains smooth even after multiple washes. Shrink proof wool also showed improved uptake of acid dyes with good fastness to washing, light, and rubbing. The proposed shrink resist process is effective and sustainable as it is a water- and chlorine-free treatment and makes use of a natural polymer reclaimed from industrial effluent as an effective substitute for chemical polymers.     

The light fading mechanism of dyes derived from rhubarb extract

The effect of relative humidity and mordanting on the fading kinetics and colour change of dyes derived from rhubarb extract on wool and silk has been investigated. Wool samples showed negligible change in colour even after 100 h of exposure, whereas silk samples became significantly darker. Relative humidity in the range of 10–45% and mordanting did not appear to affect the rate of fading on both the fibres. However, the rate and extent of change in colour (ΔE) on exposure was different for different mordants. The high resistance of the dye to light fading indicates that the dye is present in a highly aggregated form in silk and wool.     

Mapping of Oxygen Concentration in Biological Samples Using EPR Imaging

Electron paramagnetic resonance (EPR) spectroscopy is widely used for measurement and imaging of oxygen and free radicals in biological systems. EPR oximetry is non-invasive, capable of providing local, reproducible, and repetitive measurements of oxygen concentration or partial pressure of oxygen (pO₂) in tissues. Although EPR oximetry is used primarily as a research tool, it has the potential to be useful in the clinic. This review provides a brief overview of the technique and its application to selected biological systems.