Sugunan, S; Kumaree Seena, C R(Indian Journal of Chemistry, May , 1998)
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Abstract:
We have investigated the changes in surface acidity/basicity
and catalytic pro~erties of samarium oxide due to surface modification
by SO42- ion. The acidity/basicity of the catalysts is
determined by titration method using Hammett indicators.
Esterification of acetic acid by n-butanol is chosen as a test
reaction. Sm203, owing to its high basicity and low acidity, does
not catalyze the reaction. But sulphated Sm20J catalyzes the
esterification reaction effectively. Activation temperature does
not have much effect on the acidity of sulphated samaria.
Sugunan, S; Anto, Paul(Indian Journal of Chemistry, April , 1997)
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Abstract:
The surface acidity/basicity of binary oxides of Zr and La and the ternary oxides of Zr, La and Al are
reported. The data have been correlated with their catalytic activity towards liquid phase reduction of
cyclohexanone.
Sugunan, S; Bindhu, Jacob(Indian Journal of Engineering & Materials Sciences, June , 1997)
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Abstract:
The surface acidity and basicity of ternary oxides of
AI, Ce and Dy have been determined using a set of
Hammett indicators. The data have been correlated
with the catalytic activity of these oxides towards the
liquid phase reduction of cyclohexanone in 2-propanol.
The reaction is favoured by the higher basicity of
the ternary oxide.
Sugunan, S; Ampili, S; Bindhu, Jacob; Rani, Varghese(Indian Journal of Chemistry, February , 1996)
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Abstract:
The surface acidity and basicity of ternary oxides of
La, Ce and AI have been determined using a set of
Hammett indicators. The data have been correlated
with the catalytic activity of these oxides towards the
liquid phase reduction of cycIohexanone in 2-propanol.
Sugunan, S; Sunitha, Kurur; Anto, Paul(Indian Journal of Chemistry, December , 1994)
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Abstract:
The surface acidity and basicity of oxides of Sm and Zr
and their mixed oxides have been determined using a set of
Hammett indicators. The data have been correlated with
the catalytic activity of these oxides towards the liquid
phase reduction of cyclo-hexanone in 2-propanol.
Sugunan, S; Devika Rani, G; Unnikrishnan, P A(Indian Journal of Engineering & Materials Sciences, October , 1995)
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Abstract:
Acid/base strength distribution of Y2O3 and its mixed
oxides with alumina catalysts are measured on Hammett
acidity function scale and expressed in terms of H0max
value. Basicity of Y2O3 increases with increase in activation
temperature and for mixed oxides the basicity increases
with increase in concentration of Y2O3, in the catalyst.
Sugunan, S; Sherly, K B; Devika Rani, G(React. Kinet.Catal.Lett., 1993)
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Abstract:
The limit of electron transfer in electron affinity from
the oxide surface to the electron acceptor (EA) are reported
from the adsorption of EA on DY203, mixed oxides
of DY203 with alumina and mixed oxides of Y203 with y-alumina.
The extent of electron transfer is understood
from magnetic measurements.
Sugunan, S; Binsy, Varghese(Indian Journal of Chemistry, September , 1998)
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Abstract:
The electron donating properties, surface acidity/ basicity and catalytic activity of cerium - zirconium mixed
oxides at various compositions have been reported at an activation temperature of 500 degree C. The catalytic activity
for the esterification of acetic acid with n-butanol has heen correlated with electron donating properties and
surface acidity/basicity of the oxides.
The electron donating properties, surface acidity/basicity and catalytic activity of lanthana for various dopant concentrations of strontium are reported at two activation temperatures. The catalytic activity has been correlated with electron donating properties and surface acidity/basicity of the oxide.
Anantharaman, M R; Senoy, Thomas; Al-Harthi, S H; Ramanujan, R V; Zhao, Bangchuan; Liu, Yan; Wang, Lan(AIP Publishing, February 10, 2009)
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Abstract:
The growth of Fe–Ni based amorphous nanocolumns has been studied using atomic force
microscopy. The root mean square roughness of the film surface increased with the deposition time
but showed a little change at higher deposition time. It was found that the separation between the
nanostructures increased sharply during the initial stages of growth and the change was less
pronounced at higher deposition time. During the initial stages of the column growth, a roughening
process due to self shadowing is dominant and, as the deposition time increases, a smoothening
mechanism takes place due to the surface diffusion of adatoms
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.
Smitha, V K; Suja, H; Joyce, Jacob; Sugunan, S(Indian Journal of Chemistry, February , 2003)
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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.
Sugunan, S; Renuka, N K(Indian Journal of Chemistry, February , 2002)
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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
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.
Hatha, A A M; Abhirosh, Chandran; Suson, P S; Thomas, A P; Asit, Mazumder(I W A Publishing, February 11, 2013)
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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
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
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
Subha, V; Athira, Ravi(TJPRC Pvt. Ltd., March , 2013)
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Abstract:
Solid waste management nowadays is an important environmental issue in country like India. Statistics show that
there has been substantial increase in the solid waste generation especially in the urban areas. This trend can be ascribed to
rapid population growth, changing lifestyles, food habits, and change in living standards, lack of financial resources,
institutional weaknesses, improper choice of technology and public apathy towards municipal solid waste. Waste is directly
related to the consumption of resources and dumping to the land. Ecological footprint analysis – an impact assessment
environment management tool makes a relationship between two factors- the amount of land required to dispose per capita
generated waste. Ecological footprint analysis is a quantitative tool that represents the ecological load imposed on the earth
by humans in spatial terms. 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 with
special emphasis to waste generation. The paper also discusses and analyses the waste footprint of Kochi city,India. An
attempt is also made to suggest strategies to reduce the waste footprint thereby making the city sustainable, greener and
cleaner
Description:
International Journal of Civil, Structural,
Environmental and Infrastructure Engineering
Research and Development (IJCSEIERD),Vol. 3, Issue 1, Mar 2013, 67-78
Kochi, the commercial capital of Kerala, South India and 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 especially in the case of solid waste management. To have a better living condition for us and our future generations, we must know where we are now and how far we need to go. We, each individual must calculate how much nature we use and compare it to how much nature we have available. This can be achieved by applying the concept of ecological footprint. Ecological footprint analysis (EFA) is a quantitative tool that represents the ecological load imposed on earth by humans in spatial terms. 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. The paper discusses the various footprint components of Kochi city and in detail analyses the waste footprint of the residential areas using waste footprint analyzer. An attempt is also made to suggest some waste foot print reduction strategies thereby making the city sustainable as far as solid waste management is concerned.