Sasi Kumar, P R; Nampoori, V P N; Vallabhan, C P G(Elsevier, December 26, 1994)
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Abstract:
We report the experimental observation of subcritical Hopf bifurcation and the existence of non-oscillating “windows” in the dynamics of a Ne-Nd hollow cathode discharge current as the control parameter.
Philip,Mathew; Dr.Ravindranatha Menon,N(Cochin University of Science and Technology, August , 1990)
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Abstract:
The present scientific investigation of the effects of copper, mercury and cadmium has focussed on their effects on two commercially important marine bivalve species, Perna indica (brown mussel) and Donax incarnatus (wedge clam), conspicuous representatives of the tropical intertidal areas. The investigation centred around delineating the cause and effects of heavy metal stress, individually and in combination on these species under laboratory conditions. A clear understanding of the cause and effect can be had only if laboratory experiments are conducted employing sub-lethal concentrations of the above toxicants. Therefore, during the course of the investigation, sub-lethal concentrations of copper, mercury and cadmium were employed to assess the concentration dependent effects on survival, ventilation rate, O:N ratio and tissues. The results obtained are compared with the already available information and partitioned in sections to make a meaningful presentation.The thesis is presented in five chapters comprising INTRODUCTION, ACUTE TOXICITY, VENTILATION RATE, OXYGEN : NITROGEN RATIO and HISTOPATHOLOGY. Each chapter has been divided into various sections such as INTRODUCTION, REVIEW OF LITERATURE, MATERIAL AND METHODS, RESULTS and DISCUSSION
Description:
Head, Division of Marine Biology, Microbiology and
Biochemistry, School of Marine Sciences, Cochin University
of Science and Technology
Resmi, E A; Dr.Mohanakumar,K(Cochin University Of Science And Technology, September , 2012)
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Abstract:
The stratospheric warming events are categorized into major and minor
warming depending on the temperature increase in the polar stratosphere.
The warming is called a ‘major’, when the polar temperature increases
poleward from 60 degree latitude and followed by a reversal in the zonal
wind at 10 hPa (~32 Km). Usually major warming events are associated
with the displacement of polar vortex from high to mid latitudes or the
splitting of vortices in to two. The warming is called a "Minor", when the
polar temperature increases more than 25 degree in a period of a week or
less, at any stratospheric level with less intensified easterly wind anomalies. The stratospheric warmings generated during the transition
period of winter to spring are called final warmings. The warming events
observed in the early winter period (November to early December) over
Canadian region are called Canadian warmings. There is strong
interaction between stratosphere and troposphere during SSW period over
high and low latitudes regions.
The thesis consists of 7 chapters
Description:
Department of Atmospheric Sciences, Cochin
University of Science and Technology
Sunajadevi, K R; Sugunan, S(Elsevier, September , 2005)
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Abstract:
Titania, sulfated titania and chromium loaded sulfated titania were prepared by sol–gel method and characterized using different technique. Phenol is nitrated regioselectively by nitric acid using chromium loaded sulfated titania catalysts. A remarkable ortho selectivity is observed in solid state nitration to yield exclusively ortho-nitrophenol. Compared to the conventional process, phenol nitration over solid acid catalyst is a clean and environment friendly process. Catalytic activity well correlates with the Brönsted acid sites of these catalysts.
Rosily, A V; Dr.Chandramohanakumar, N(Cochin University of Science & Technology, December , 2002)
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Abstract:
Sulphur is a non conservative major element and is the most active species in the redox processes in nature, especially in aquatic environment . The varying oxidative states from-2 to +6 make it possible to enter into many of the biogeochemical processes. Thus the history, present and future of the chemical composition and behaviour of the natural aquatic systems and sediments have footprints of the sulphur chemistry.Mangroves are considered to be the most productive, fishery supportive ecosystem operating in the intertidal regions. The interlinking of the mangroves with the sulphur chemistry is attempted here.
Description:
Department of Chemical Oceanography, Cochin University of Science and Technology
Paulose,C S; Athira, Babu; Anju, T R(Indian Journal of Biochemistry and Biophysics, April , 2009)
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Abstract:
Hypoxia is one of the major causes of damage to the fetal and neonatal brain and cardiac functions. in earlier studies we have reported the brain damage caused by hypoxia and resusciation with oxygen and epinephrine and have found that glucose treatment to hypoxic rats and hypoxic rats treated with oxygen shows a reversal of brain damage. during this study the findings may have clinical significance in the proper management of heart and brain functions.
Kemthose,P Paul; Dr.Bhasi, M(School of Management Studies, Faculty of Social Sciences, 2003)
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Abstract:
Model development for selection of location for refinery in India and identification of characteristics to be looked into when configuring it and to develop models for integrated supply chain planning for a refinery. Locating and removing inbound, internal and outbound logistic problems in an existing refinery and overall design of a logistic information system for a refinery are the main objectives of the study. A brief description of supply chain management (SCM), elements of SCM and their significance, logistics cost in petroleum industry and its impacts, and dynamics of petroleum its logistic practices are also to be presented. Scope of application of SCM in petroleum refinery will also be discussed. A review of the investigations carried out by earlier researches in the area of supply chain management in general and with specific reference to petroleum refining.
Maya, C Pillai; Rajasenan, D(Ccchin University of Science and Technology, 2003)
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Abstract:
The study deals with the short and long term supply response of the natural rubber in India and to analyse the macro economic environment of NR industry and causative factors of the rubber price crash. It determines the minimum cost of production of natural rubber and to forecast the potential production of NR in India. There is positive response of short run and long run supply to prices. Since correlation analysis show close association between international and domestic price level, international price changes will have its domestic echo. Production and consumption will sustain its rising trend. This makes plans for increasing production estimates show that a mid way level i.e. the range between Rs.32-Rs.38 will give a fair enough profit to the grower in the present situation and provide for the viable sustenance of rubber cultivation. Identification of the SWOT of rubber cultivation would help in supporting rubber cultivation if remedial measures are undertaken with the true spirit. This would help Indian rubber to attain global competitiveness. Then the inflow of valuable foreign exchange will overcome the other economic drawbacks of rubber cultivation
Thomas, Kuruvilla; Nandakumaran, V M(Elsevier, April , 1999)
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Abstract:
The effect of coupling on two high frequency modulated semiconductor lasers is numerically studied. The phase diagrams and bifurcatio.n diagrams are drawn. As the coupling constant is increased the system goes from chaotic to periodic behavior through a reverse period doubling sequence. The Lyapunov exponent is calculated to characterize chaotic and periodic regions.
Yoosaf, K; Dr. George Thomas, K(Chemical Sciences and Technology Division,CSIR, January , 2008)
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Abstract:
Most of the procedures reported for the synthesis of metal
nanoparticles involve the use of strong reducing agents or elevated
temperatures. This limits the possibility of developing metal nanoparticle
based sensors for the in situ detection of analytes. One of the objectives of
the present investigations is to (i) develop newer methodologies for the
synthesis of metal nanoparticles in aqueous medium at ambient conditions
and (ii) their use in the detection of metal cations by taking advantage of
the unique coordination ability. Ideally, biocompatible molecules which
possess both the reducing and stabilizing groups are desirable for such
applications. Formation of stable supramolecular assembly, by bringing metal nanoparticles close to each other, results in plasmon coupling and
this strategy can be effectively utilized for the development of metal
nanoparticle based sensors.Another objective of the present study is to understand the
supramolecular organization of molecules on surfaces. Various
noncovalent interactions between the molecules and with surface play a
decisive role in their organizations. An in-depth understanding of these
interactions is essential for device fabrications. Recent photophysical
studies have revealed that phenyleneethynylene based molecular systems
are ideal for device application. The second objective of the thesis focuses
on understanding the (i) organization of phenyleneethynylenes on highly
oriented pyrolytic graphite (HOPG) surface with atomic level precision and
(ii) weak intermolecular interactions which drive their organization.
Sugunan, S; Rahna, K S(Indian Journal of Chemistry, July , 2002)
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Abstract:
The incorporation of transition metal oxide pillars such as those of iron and chromium along with Al2O3, pillars within
the interlayers of a montmorillonite clay is investigated. The surface acidity of these catalysts has been evaluated for the first
time employing the equilibrium adsorption of an electron donor, perylene, and the results are compared with those obtained
by temperature programmed desorption of ammonia. The principle is based on the ability of a catalyst surface site to accept
a single electron from an electron donor like perylene to form charge transfer complexes and the amount of adsorbed species
is measured quantitatively by UV-vis spectroscopy. Fina1ly, an attempt has been made to correlate the acidity determined by
the two independcnt methods and the catalytic activity of present systems in the benzoylation of toluene with benzoyl
chloride. Incorporation of Fe and Cr has changed the properties of AI pitlared montmorillonite. Fe pillared systems have
been found to be vcry good catalysts for benzoylation reaction
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.