Abstract: | Ferrospinels of nickel, cobalt and copper and their sulphated analogues were prepared by the room temperature coprecipitation route to yield samples with high surface areas. The intrinsic acidity among the ferrites was found to decrease in the order: cobalt> nickel> copper. Sulphation caused an increase in the number of weak and medium strong acid sites, whereas the strong acid sites were left unaffected. Electron donor studies revealed that copper ferrite has both the highest proportion of strong sites and the lowest proportion of weak basic sites. All the ferrite samples proved to be good catalysts for the benzoy lation of toluene with benzoyl chloride. copper and cobalt ferrites being much more active than nickel ferrite. The catalytic activity for benzoylation was not much influenced by sulphation, but it increased remarkably with calcination temperature of the catalyst. Surface Lewis acid sites, provided by the octahedral cations on the spinel surface, are suggested to be responsible for the catalytic activity for the benzoylation reaction. |
URI: | http://dyuthi.cusat.ac.in/purl/2280 |
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Dyuthi-SS63.pdf | (653.0Kb) |
Abstract: | In recent years considerable advances have been achieved in the study of the surface structure and mechanism of action of environmentally benign heterogeneous catalysts. The study entitled as surface properties and catalytic activity of manganese ferrospinels. In the present study we have prepared manganese ferrospinels of general formula Mn(1-x)BxFe2O4 via low temperature controlled co-precipation method. The study employed low temperature co-precipitation method for the preparation ofMn(1-x)BxFe2O4 specimens, where B is a metal cation such as Cr,Co, Ni,Cu and Zn. The catalytic activities of the systems were investigated for liquid-phase benzoylation of aromatic compounds and phenol hydroxylation and for vapour-phase reactions such as aniline alkylation, phenol methylation and ODH of ethylbenzene. The different series of manganese ferrites are proved to be excellent catalysts for various industrially important reactions such as Friedel-crafts benzoylation of aromatic compounds, methylation of aniline and phenol, hydroxylation of phenol and oxidative dehydrogenation of ethylbenzene. Due to the tightening of the environmental regulations, production of diphenols from phenol hydroxylation and reduction of phenolic pollutants in waste waters using these catalysts can be a promising approach because it demands only simple techniques and produce little environmental pollution. |
URI: | http://dyuthi.cusat.ac.in/purl/946 |
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Dyuthi-T0287.pdf | (9.299Mb) |
Abstract: | Preparation and physico-chemical characterization or phosphate modified zirconia systems and their application to Friedel-Crafts benzylation and benzoylation of toluene have been reported. The influence of transition metals on the surface properties and catalytic activity has also been discussed. |
URI: | http://dyuthi.cusat.ac.in/purl/2283 |
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Dyuthi-SS65.pdf | (243.3Kb) |
URI: | http://dyuthi.cusat.ac.in/purl/1717 |
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Dyuthi-T0299.pdf | (3.226Mb) |
Abstract: | An investigation on the physical and chemical characterisation of rare earth oxide supported vanadia is attempted in the present study. La2O3, Sm2O3 and DY2O3 serve the purpose of supports. Supported catalysts were prepared and characterised using various physico chemical techniques. A detailed investigation of acid base properties is also carried out. The nature of interaction of vanadia with lanthanide oxide is discussed and the effect of vanadia loading on the activity of the systems towards reactions of industrial importance is explored. |
Description: | Department of Applied Chemistry, Cochin University of Science and Technology |
URI: | http://dyuthi.cusat.ac.in/purl/2192 |
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Dyuthi-T0539.pdf | (5.119Mb) |
Abstract: | Sm2O3 - vanadia catalysts have been prepared by wet impregnation method using NH4VO3 solution. The surface properties of the prepared catalysts have been studied using FTIR. XRD. surface area and pore volume data. The acid-base properties of the system have been investigated by titrimetric method using Hammett indicators. adsorption of electron acceptors as well as decomposition of cyclohexanol. Phenol alkylation reaction by methanol has been carried out to investigate the catalytic activity. It has been observed that the selectivity of the products depends upon the composition of the supported system |
URI: | http://dyuthi.cusat.ac.in/purl/2212 |
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Dyuthi-SS15.pdf | (391.7Kb) |
URI: | http://dyuthi.cusat.ac.in/purl/1101 |
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Vijayakumar K P 1984.pdf | (1.340Mb) |
Abstract: | The thesis aims to present the results of experimental investigations on the changes of optical properties of metallic thin films due to heating. The parameters which are measured are reflectivity, refractive indices and the ellipsometric quantities V and A . The materials used in the studies are metals like Silver, Aluminium and Copper. By applying the optical method the interdiffusion taking place in multilayer ‘films of Aluminium and Silver has also been studied. Special interest has been taken to reveal the mechanisms of the hillock growth and surface roughness caused by heating and their relation with the stress in the film |
Description: | Department of Physics, Cochin University of Science and Technology |
URI: | http://dyuthi.cusat.ac.in/purl/3649 |
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Dyuthi-T1634.pdf | (5.044Mb) |
Abstract: | The advancements in medical science and technology have proved to be a boon to mankind. At the same time they have raised numerous challenges before the legal systems of the world. One such advancement is that of assisted human reproductive technologies and particularly surrogacy, which have given a new meaning to the concept of procreation. These technologies have made it possible for individuals to beget a genetically related child with the help of a third party and without sexual intercourse. Among all the assisted human reproductive technologies, the practice of surrogacy, in which women agree to have their bodies used to undergo a pregnancy and give birth to a baby for another, has raised various legal and human right controversies and diverse legal responses all over the world. India has particularly become a top destination for individuals who wish to beget a child through surrogacy and hence it is imperative for the Indian government to address the challenges posed by surrogacy. This study is an attempt to examine the need and importance of surrogacy practices and the conflicting legal and human rights issues raised by surrogacy in contemporary times. It also examines the adequacy of existing legal framework in India and attempts to provide pragmatic solutions for regulating surrogacy and protecting the interests of various stakeholders involved in surrogacy. |
URI: | http://dyuthi.cusat.ac.in/purl/5066 |
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Dyuthi-T2129.pdf | (7.943Mb) |
Abstract: | The present study aims at surveying the coral lagoons of four islands viz. Kavarathi, Kalpeni, Kadmat and Agathi, which include quantitative survey of the major benthic forms using Line Intercept Transect (LIT) technique and hydrographical study of these lagoon waters The distribution of PHC in the lagoons has also been followed to understand, the effects of introduction of flat bottomed ferry boats to the islands.From a biological monitoring stand point for the assessment of manmade disturbance of the coral reefs, it IS highly essential to identify faunal assemblages which will contain 'flag-stones' specIes as indicators of such disturbances. Among the known faunal assemblages In coral reefs the most diverse groups of sensitive species belongs to bryozoan assemblage. Therefore, the most common species of bryozoans distributed along the atolls and reef flats were collected and described in this work Along with this, bryozoans associated with coral from other parts of Indian ocean have also been added so as to provide a comprehensive picture of the distribution of bryozoans in the coral reefs. |
Description: | Department of Marine Biology, Cochin University of Science and Technology |
URI: | http://dyuthi.cusat.ac.in/purl/3400 |
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Dyuthi-T1377.pdf | (4.172Mb) |
URI: | http://dyuthi.cusat.ac.in/purl/1669 |
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Dyuthi-T0297.pdf | (1.856Mb) |
Abstract: | The survival of Escherichia coli in tropical estuarine water has been studied under controlled laboratory conditions using microcosms. The survival has been assessed in terms of various self purifying factors of the natural waters such as biological, chemical and physical factors. The biological factors considered included competition from other microorganisms, predation by protozoa and coliphages. The suitability of the chemical composition of estuarine water has been studied under chemical factors and negative impact of sunlight has been studied under physical factors. The results revealed that sunlight exerted maximum negative impact, followed by biotic factors contained in the estuarine water. However, the chemical composition of the estuarine water is found to be suitable for the growth and survival of E. coli. The injury exerted by each of the above factors was also evaluated by using a selective and non-selective medium in conjunction. It was found that sunlight resulted in 100% injury of the cells as the cells failed to develop in a selective medium. While, sunlight resulted in the extinction of 90% of the E. coli cells within the first two hours of exposure, biotic factors took nearly 24 hours to remove the same amount of population. |
Description: | S. Pac. J. Nat. Sci. 2003, 21, 41-46 |
URI: | http://dyuthi.cusat.ac.in/purl/3957 |
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Survival of Esc ... in a tropical estuary.pdf | (38.45Kb) |
Abstract: | The objective of the study was to evaluate the survival response of multi-drug resistant enteropathogenic Escherichia coli and Salmonella paratyphi to the salinity fluctuations induced by a saltwater barrier constructed in Vembanadu lake, which separates the lake into a freshwater dominated southern and brackish water dominated northern part. Therefore, microcosms containing freshwater, brackish water and microcosms with different saline concentrations (5, 10, 15, 20, 25 ppt) inoculated with E. coli/S. paratyphi were monitored up to 34 days at 20 and 30 WC. E. coli and S. paratyphi exhibited significantly higher (p <0.05) survival at 20 WC compared to 30 WC in all microcosms. Despite fresh/brackish water, E. coli and S. paratyphi showed prolonged survival up to 34 days at both temperatures. They also demonstrated better survival potential at all tested saline concentrations except 25 ppt where a significantly higher (p<0.0001) decay was observed. Therefore, enhanced survival exhibited by the multi-drug resistant enteropathogenic E. coli and S. paratyphi over a wide range of salinity levels suggest that they are able to remain viable for a very long time at higher densities in all seasons of the year in Vembanadu lake irrespective of saline concentrations, and may pose potential public health risks during recreational activities |
Description: | Journal of Water and Health | 11.2 | 2013 |
URI: | http://dyuthi.cusat.ac.in/purl/3918 |
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Survival of mul ... stant enteropathogenic.pdf | (371.4Kb) |
Abstract: | The Indian ornamental fish industry is divided into two-the domestic market and the export market. 90% of the freshwater ornamental fish exported from India are wild caught indigenous species. The study formed the criteria and indicators assessing the sustainability of wild caught ornamental fish exported from India. These indicators were then analyzed for their interactions, connections, linkages and relationships using cognitive mapping. The work is first of its kind in the ornamental fisheries |
URI: | http://dyuthi.cusat.ac.in/purl/4956 |
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Dyuthi-T2032.pdf | (6.142Mb) |
Description: | Dept.of Applied Economics,Cochin University of Science and Technology |
URI: | http://dyuthi.cusat.ac.in/purl/3000 |
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Dyuthi-T0980.pdf | (3.944Mb) |
Abstract: | The present study on the sustainability of medicinal plants in Kerala economic considerations in domestication and conservation of forest resources. There is worldwide consensus on the fact that medicinal plants are important not only in the local health support systems but in rural income and foreign exchange earnings. Sustainability of medicinal plants is important for the survival of forest dwellers, the forest ecosystem, conserving a heritage of human knowledge and overall development through linkages. More equitable sharing of the benefits from commercial utilization of the medicinal plants was found essential for the sustainability of the plants. Cultivation is very crucial for the sustainability of the sector. Through a direct tie-up with the industry, the societies can earn more income and repatriate better collection charges to its members. Cultivation should be carried out in wastelands, tiger reserves and in plantation forests. In short, the various players in the in the sector could find solution to their specific problems through co-operation and networking among them. They should rely on self-help rather than urging the government to take care of their needs. As far as the government is concerned, the forest department through checking over- exploitation of wild plants and the Agriculture Dept. through encouraging cultivation could contribute to the sustainable development of the medicinal plant sector. |
URI: | http://dyuthi.cusat.ac.in/purl/52 |
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Dyuthi-T0291.pdf | (2.343Mb) |
Abstract: | The study has wider policy implications as it identifies the possible variables which influence the sustainability of participatory productive sector projects. The method which is developed to study the sustainability of projects under People’s Planning in Chempu Panchayat could be used for studying the same in other panchayats also. Unlike the case of the standard features of sustainability identified, the independent variables vary according to the nature of the project. Hence, this needs to be modified accordingly while applying the method in a dissimilar domain. Selection of a single panchayat for the present study is relevant on the basis of a common package of inputs for decentralised planning which is forwarded by the State Planning Board respectively for the three-tier panchayat system in Kerala. The dynamic filed realities could be brought out in view of a comprehensive planning approach through an in depth study of specific cases.The assessment of the nature and pattern of productive sector projects in the selected Village Panchayat puts the projects under close scrutiny. The analysis has depended largely on secondary sources of information, especially from panchayat level plan documents, and also on the primary information obtained using direct observation and on-site inspection of project sites. An analysis of the nature and pattem of productive sector projects is important as it gives all necessary information regarding follow-up, monitoring/evaluation and even termination of a particular project. It has also revealed the tendencies of including infrastructure and service sector projects under ‘productive’ category, especially for maintaining the stipulated ratio (40:30:30) of grant-in-aid distribution. The study regarding the allocation and expenditure pattern of plan funds is vital in policy level as it reveals the under-noticed allocation and expenditure pattern of plan funds other than grant-in-aid. One major limitation of the study has been the limited availability of secondary data, especially regarding project-wise expenditure and monitoring/evaluation reports of various project committees. |
Description: | Department of Applied Economics, Cochin University of Science and Technology. |
URI: | http://dyuthi.cusat.ac.in/purl/2970 |
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Dyuthi-T0959.pdf | (7.868Mb) |
URI: | http://dyuthi.cusat.ac.in/purl/2480 |
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Dyuthi-T0663.pdf | (13.56Mb) |
Abstract: | Kerala, God’s own country is blessed with immense natural resources. It’s high time that the state’s natural resources being utilized effectively. While sustainable development is the need of the hour, we have to take lead in initiating activities that would minimize the exploitation of our natural resources resulting in their effective utilization. This paper narrates an overview of innovative building materials especially using natural fibres available in Kerala and discusses the feasibility of utilising such fibres in the context of sustainable building materials in Kerala. The paper also discusses how these materials can be effectively utilized to reduce the huge investment in the construction industry |
Description: | ACEEE Int. J. on Transportation and Urban Development, Vol. 01, No. 01, Apr 2011 |
URI: | http://dyuthi.cusat.ac.in/purl/4635 |
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Sustainable Bui ... n Kerala – An overview.pdf | (89.48Kb) |
Abstract: | In the past, natural resources were plentiful and people were scarce. But the situation is rapidly reversing. Our challenge is to find a way to balance human consumption and nature’s limited productivity in order to ensure that our communities are sustainable locally, regionally and globally. Kochi, the commercial capital of Kerala, South India and the second most important city next to Mumbai on the Western coast is a land having a wide variety of residential environments. Due to rapid population growth, changing lifestyles, food habits and living standards, institutional weaknesses, improper choice of technology and public apathy, the present pattern of the city can be classified as that of haphazard growth with typical problems characteristics of unplanned urban development. Ecological Footprint Analysis (EFA) is physical accounting method, developed by William Rees and M. Wackernagel, focusing on land appropriation using land as its “currency”. It provides a means for measuring and communicating human induced environmental impacts upon the planet. The aim of applying EFA to Kochi city is to quantify the consumption and waste generation of a population and to compare it with the existing biocapacity. By quantifying the ecological footprint we can formulate strategies to reduce the footprint and there by having a sustainable living. In this paper, an attempt is made to explore the tool Ecological Footprint Analysis and calculate and analyse the ecological footprint of the residential areas of Kochi city. The paper also discusses and analyses the waste footprint of the city. An attempt is also made to suggest strategies to reduce the footprint thereby making the city sustainable |
Description: | International Journal of Scientific & Engineering Research, Volume 4, Issue 4, April-2013 |
URI: | http://dyuthi.cusat.ac.in/purl/4637 |
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Sustainable Dev ... y in Kochi City, India.pdf | (230.3Kb) |
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