Cochin University of Science and Technology

About: Cochin University of Science and Technology is a education organization based out in Kochi, Kerala, India. It is known for research contribution in the topics: Thin film & Natural rubber. The organization has 5382 authors who have published 7690 publications receiving 103827 citations. The organization is also known as: CUSAT & Cochin University.

Titanium dioxide based self-cleaning smart surfaces: A short review

Abstract: The bio-inspired nanotechnology of self-cleaning surfaces and coatings are nowadays being much attracted in the field of energy and environment because of the ever-increasing demand of uncontaminated, self-disinfected and hygienic surfaces. Such surfaces/coatings can be adopted on glass windows, automobile windshields, anti-fouling membranes, textiles, building construction materials, paints; on optoelectronic devices like solar panels, photochromic glasses, etc; in the food industry and for medical aids. This review gives a special emphasis to superhydrophilic self-cleaning surfaces. The mechanism of photocatalytic self-cleaning and superhydrophilicity of nano TiO2 based systems is carefully investigated. The photogenerated reactive oxygen species generated during photoexcitation of electrons from the valence band to the conduction band of TiO2 is responsible for its photocatalytic behaviour, anti-bacterial property and superhydrophilicity. Emphasis is given on various systems and methods that could enhance the self-cleaning behaviour of TiO2 in the solar spectrum since pristine TiO2 is only ultraviolet responsive. TiO2-semiconductor heterojunctions, hybrids of TiO2 with graphene and graphitic monolayers, tailoring the exposed crystal facets in TiO2, metal and non-metal doping and dye sensitization, attributing to visible light photocatalytic self-cleaning activity are focused in detail. Various techniques adopted for the synthesis and fabrication of superhydrophilic self-cleaning materials and coatings are discussed.

A baseline study of trace metals in a coral reef sedimentary environment, Lakshadweep Archipelago

Abstract: Surficial and core samples collected from the sedimentary microenvironments of Lakshadweep Archipelago were analysed for their trace metal contents. The synoptical relations in spatial distributions with respect to environmental conditions such as pH, organic carbon and sediment texture were inter-correlated. Some of the metals exhibited good correlations with Fe/Mn, which reflect their similarity in distribution rather than anthropogenic enrichment. Inter-relating the variations in metal—pH relationships with metal—organic carbon, in general, those which exhibited positive correlations with pH, displayed negative interactions with organic carbon content and vice versa. Comparatively, higher values of Fe in the mangrove area of one of the islands highlight the possibility of precipitation of Fe as iron sulphides, which are common in mangrove ecosystem. Based on the contamination factors for Pb, Zn and Cd, as well as the geo-accumulation index of Cd, it can be generalised that some of the islands remain polluted with respect to these elements. An evaluation based on pollution load index shows that none of the islands surveyed for this study posed a serious threat in trace metal pollution. Bray Curtis similarity index was computed to find out the similarity among metals/islands, using non-transformed data of metal concentrations. Group linkage clustering technique was used for drawing dendrograms to show the similarity among them.

Thioglycolic acid capped CdS quantum dots as a fluorescent probe for the nanomolar determination of dopamine

Abstract: Thioglycolic acid (TGA) capped CdS quantum dots (QDs) have been successfully employed as an efficient nano sized fluorescent probe for the selective determination of dopamine (DA) in acetate buffer solution (pH 7). The fluorescence emission spectrum of TGA functionalized CdS QDs which was at about 527 nm showed an enormous increase in emission intensity in the presence of DA. The linear range and detection limit of the developed turn on sensor were 3.94 × 10−7 to 4.67 × 10−8 M and 2.55 × 10−9 M, respectively. The addition of DA increases the passivation of surface traps of QDs thereby increasing the fluorescence emission intensity. The influence of some biologically important species that are structurally similar to DA on the fluorescence emission intensity of the CdS fluorescent probe was studied to evaluate the selectivity of the sensor. The developed turn on sensor exhibits good analytical figures of merit and excellent selectivity and shows promising practical applications.

Sustainable Land-based Aquaculture: Rational Utilization of Water, Land and Feed Resources

Abstract: Much has been said on the need to practice aquaculture in a sustainable manner, preferably without jeopardizing the environment (Naylor, et al. 2000 and FAO 1997). As a result, best management practices for the aquaculture industry, considering environmental, economic and social sustainability, have been established (e.g. www.gaalliance.org/bap.html). Standards of some organizations for organic farming restrict stocking density and maximum pond biomass per unit surface area. For example, to produce organic shrimps, less than 15 postlarvae (PL) per square meter should be stocked with shrimp biomass always remaining below 800kg/ha (e.g. Naturland standards 2004; www.naturland.de/ englisch/n2/NL-Stand-Aquaculture_01-2005. pdf). These rules were mainly put forward to protect shrimp health and welfare, and to avoid the development of diseases. Naylor et al. (2000) stated that “intensification implies increasing the density of individuals, which requires greater use and management of inputs and greater generation of waste products”. Such rules or statements suggest that intensification will always lead to the production of more wastes or to a reduction of animal welfare, which should be avoided.