Sugunan, S(Indian Journal of Chemistry, September , 1984)
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Abstract:
The Setschenow parameters of solubility in salt solutions and the
thermodynamic parameters (25·C) of transfer from aqueous
solution to aqueous salt solutions for 2-nitrobenzoic acid and 3-nitrobenzoic
acid have been reported. The data have been
rationalized on the basis of the localized hydrolysis model and the
structure breaking action of ions of the electrolytes.
Sugunan, S; Thomas, B(American Chemical Society, 1995)
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Abstract:
The Setschenow parameter and thermodynamic parameters of transfer of 2- and 4-aminobenzoic acids
from water to salt solutions have been reported. The results are discussed in terms of the structure- breaking
effects of the ions of the salts, the localized hydrolysis model, and the internal pressure theory.
Sugunan, S; Benny, Thomas(Indian Journal of Chemistry, July , 1993)
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Abstract:
The Setschenow parameter and thermodynamic parameters of transfer of a number of monosubstituted
benzoic acids from water to different salt solutions have been reported. The data have been rationalized by
considering the structure breaking effects of the ions of the salts, the localised hydrolysis model, the internal
pressure theory and Symons' theory of water structure.
Hareeshkumar, P V; Dr.Basil, Mathew(Cochin University of Science And Technology, January , 1992)
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Abstract:
The Arabian Sea is an area of complex air-sea interaction
processes with seasonal reversing monsoons. The associated
thermohaline variability in the upper layers appears to
control the large scale monsoon flow which is not yet
completely understood.
The variability in the thermohaline fields is known to
occur in temporal domain ranging from intra-diurnal to
inter-annual time scales and on spatial domains of few tens of
kilometers to few thousands of kilometers. In the Arabian Sea
though the surface temperature was routinely measured by both
conventional measurements and satellites, the corresponding
information on the subsurface thermohaline field is very
sparse due to the lack cw adequate measurements. In such
cases the numerical models offer promise in providing
information on the subsurface features given an initial
thermohaline field and surface heat flux boundary conditions.
This thesis is an outcome of investigations carried out
on the various aspects of the thermohaline variability on
different time scales. In addition to the description of the
mean annual cycle. the one dimensional numerical models of
Miller (1976) and Price et a1 (1986) are utilised to simulate
the observed mixed layer characteristics at selected locations
in the Arabian Sea on time scales ranging from intra-diurnal
to synoptic scales under variable atmospheric forcing.
Anju, K. Augustine; Dr.Kailasnath, M; Prof. V P N Nampoori(Cochin University of Science and Technology, June 23, 2015)
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Abstract:
In general, linear- optic, thermo- optic and nonlinear- optical studies
on CdSe QDs based nano
uids and their special applications in solar
cells and random lasers have been studied in this thesis. Photo acous-
tic and thermal lens studies are the two characterization methods used
for thermo- optic studies whereas Z- scan method is used for nonlinear-
optical charecterization. In all these cases we have selected CdSe QDs
based nano
uid as potential photonic material and studied the e ect of
metal NPs on its properties.
Linear optical studies on these materials have been done using vari-
ous characterization methods and photo induced studies is one of them.
Thermal lens studies on these materials give information about heat
transport properties of these materials and their suitability for applica-
tions such as coolant and insulators. Photo acoustic studies shows the
e ect of light on the absorption energy levels of the materials. We have
also observed that these materials can be used as optical limiters in the
eld of nonlinear optics. Special applications of these materials have
been studied in the eld of solar cell such as QDSSCs, where CdSe QDs
act as the sensitizing materials for light harvesting. Random lasers have
many applications in the eld of laser technology, in which CdSe QDs
act as scattering media for the gain.
Santhosh, B; Dr.Nandakumar, C G(Cochin University of Science & Technology, December , 2010)
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Abstract:
Three dimensional (3D) composites are strong contenders for the structural applications in situations like aerospace,aircraft and automotive industries where multidirectional thermal and mechanical stresses exist. The presence of reinforcement along the thickness direction in 3D composites,increases the through the thickness stiffness and strength properties.The 3D preforms can be manufactured with numerous complex architecture variations to meet the needs of specific applications.For hot structure applications Carbon-Carbon(C-C) composites are generally used,whose property variation with respect to temperature is essential for carrying out the design of hot structures.The thermomechanical behavior of 3D composites is not fully understood and reported.The methodology to find the thermomechanical properties using analytical modelling of 3D woven,3D 4-axes braided and 3D 5-axes braided composites from Representative Unit Cells(RUC's) based on constitutive equations for 3D composites has been dealt in the present study.High Temperature Unidirectional (UD) Carbon-Carbon material properties have been evaluated using analytical methods,viz.,Composite cylinder assemblage Model and Method of Cells based on experiments carried out on Carbon-Carbon fabric composite for a temparature range of 300 degreeK to 2800degreeK.These properties have been used for evaluating the 3D composite properties.From among the existing methods of solution sequences for 3D composites,"3D composite Strength Model" has been identified as the most suitable method.For thegeneration of material properies of RUC's od 3D composites,software has been developed using MATLAB.Correlaton of the analytically determined properties with test results available in literature has been established.Parametric studies on the variation of all the thermomechanical constants for different 3D performs of Carbon-Carbon material have been studied and selection criteria have been formulated for their applications for the hot structures.Procedure for the structural design of hot structures made of 3D Carbon-Carbon composites has been established through the numerical investigations on a Nosecap.Nonlinear transient thermal and nonlinear transient thermo-structural analysis on the Nosecap have been carried out using finite element software NASTRAN.Failure indices have been established for the identified performs,identification of suitable 3D composite based on parametric studies on strength properties and recommendation of this material for Nosecap of RLV based on structural performance have been carried out in this Study.Based on the 3D failure theory the best perform for the Nosecap has been identified as 4-axis 15degree braided composite.
Description:
Dept.of Ship Technology,Cochin University of Science and Technology
Unnikrishnan, K P; Jayan,Thomas; Nampoori, V P N; Vallabhan, C P G(Elsevier, April 1, 2002)
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Abstract:
Third order nonlinear susceptibility χ(3) and second hyperpolarizability (γ) of a bis-naphthalocyanine viz. europium naphthalocyanines, Eu(Nc)2, were measured in dimethyl formamide solution using degenerate four wave mixing at 532 nm under nanosecond pulse excitation. Effective nonlinear absorption coefficient, βeff and imaginary part of nonlinear susceptibility, Im(χ(3)) were obtained using open aperture /Z-scan technique at the same wavelength. Optical limiting property of the sample was also investigated. The role of excited state absorption in deciding the nonlinear properties of this material is discussed.
This manuscript describes the first example of silver ion complex of a dendritic tetranitrile ligand catalyzed
one-pot three component Mannich reaction and 1,5-benzodiazepine synthesis. The catalyst can be separated from the
products by a change in the solvent. The catalyst is reusable.
In this paper we try to fit a threshold autoregressive (TAR) model to time series data of monthly coconut oil prices at Cochin market. The procedure proposed by Tsay [7] for fitting the TAR model is briefly presented. The fitted model is compared with a simple autoregressive (AR) model. The results are in favour of TAR process. Thus the monthly coconut oil prices exhibit a type of non-linearity which can be accounted for by a threshold model.
Dakshinamurti,K; Paulose,C S; Thliveris,J A; Vriend,J(Department of Biotechnology, August 15, 1984)
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Abstract:
In pyridopaminedoxine-deficient young rats hypothalamic serum TSH concentration was detected. Highly signifiserotonin
was decreased with no changes in the cant decreases in the content of pituitary TSH and in
and noradrenaline content. Serum the number of pituitary thyrotroph secretory granules
and tri-iodothyronine concentrations were were found. These results suo
mmuuchch lower in the deficient rats as compared to thyroidism of suggest that the hypocontrols.
No significant of hypothalamicp yorirdigoxinin.e -deficient young rats might bbee
difference between deficient and control groups in the
Shivaprasad,Amaravayal; Dr.Revichandran,C(Cochin University Of Science And Technology, May , 2013)
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Abstract:
Hydrodynamic characteristics of an estuary resulting from
interaction of tide and river runoff are important since problems
regarding flood, salinity intrusion, water quality, ecosystem and sedimentation are ubiquitous. The present study focuses on such
hydrodynamic aspects in the Cochin estuary.
Most of the estuaries that come under the influence of Indian
Summer Monsoon and for which the salinity is never in a steady
state at any time of the year are generally shallow and convergent,
i.e. the width decreases rapidly from mouth to head. In contrast,
Cochin estuary is wider towards the upstream and has no typical
river mouth, where the rivers are joining the estuary along the length
of its channel .Adding to the complexity it has dual inlets and the
tidal range is 1 m which is lower than other Indian estuaries along
west coast. These typical physical features lead to its unique
hydrodynamic characteristics. Therefore the thesis objectives are: I)
to study the influence of river runoff on tidal propagation using
observations and a numerical model ii) to study stratification and
property distributions in Cochin estuary iii) to understand salinity
distributions and flushing characteristics iv) to understand the
influence of saltwater barrage on tides and salinity v) To evaluate
several classification schemes for the estuary
Description:
National Institute of Oceanography, Regional centre, Cochin- 18
Suresh, V N; Dr.Wilson, P R(Cochin University of Science And Technology, June , 2000)
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Abstract:
Poor project planning, implementation and control and the subsequent cost and time overruns are ubiquitous features that have been posing serious concern at all levels - state, national and international. It results in wastage of the nation's scarce resources and retards the socio-economic progress. Although several studies peripheral on project overruns have been made at the national level, no serious attempt has been made at the state level to identify the magnitude of overruns, their causes and impacts on industrial projects. The present study "Time and Cost Overruns of Industrial Projects in Kerala" is an earnest attempt to probe in depth the time and cost overruns and their impact on industrial projects. The study places emphasise on the identification of the real reasons behind the cost and time overruns. It also covers the present project management practices of industrial projects in Kerala.
Description:
School of management studies, Cochin University of Science And Technology
Padmaja, G; Ravi Kumar, A V; Vidyalal, V; Radhakrishnan, P; Nampoori, V P N; Vallabhan, C P G(IOP Publishing, 1989)
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Abstract:
In order to characterise the laser ablation process from high-Tc superconductors, the time evolution of plasma produced by a Q-switching Nd:YAG laser from a GdBa2Cu3O7 superconducting sample has been studied using spectroscopic and ion-probe techniques. It has been observed that there is a fairly large delay for the onset of the emission from oxide species in comparison with those from atoms and ions of the constituent elements present in the plasma. Faster decay occurs for emission from oxides and ions compared with that from neutral atoms. These observations support the view that oxides are not directly produced from the target, but are formed by the recombination process while the plasma cools down. Plasma parameters such as temperature and velocity are also evaluated.
Harilal, S S; Bindhu, C V; Nampoori, V P N; Vallabhan, C P G(Springer Berlin / Heidelberg, 1998)
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Abstract:
Laser radiation at 1.06 µm from a pulsed Nd:YAG
laser was focused onto a multielement YBa2Cu3O7 target in
vacuum and the plasma thus generated was studied using
time-resolved spectroscopic techniques. Line broadening of
the Ba I emission line at 553.5 nm was monitored as a function
of time elapsed after the incidence of a laser pulse on the
target. Measured line profiles of barium species were used to
infer the electron density and temperature, and the time evolution
of these important plasma parameters has been worked out.