| URI: | http://dyuthi.cusat.ac.in/purl/1215 |
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| Prabhudeva K N 1988.PDF | (320.3Kb) |
| Abstract: | In this thesis certain important aspects of heavy metal toxicity have been worked out. Recent studies have clearly shown that when experimental media contained more than one heavy metals, such metals could conspicuously influence the toxic reaction of the animals both in terms of quantity and nature. The experimental results available on individual metal toxicity show that, in majority of such results, unrealistically high concentrations of dissolved metals are involved. A remarkable number of factors have been shown to influence metal toxicity such as various environmental factors particularly temperature and salinity, the condition of the organism and the ability of some of the marine organisms to adapt to metallic contamination. Further, some of the more sensitive functions like embryonic and larval development, growth and fecundity, oxygen utilization and the function of various enzymes are found to be demonstrably sensitive in the presence of heavy metals. However, some of the above functions could be compensated for by adaptive process. If it is assumed that the presence of a single metal in higher concentrations could affect the life function of marine animals, more than one metal in the experimental media should manifest such effects in a greater scale. Commonly known as synergism or more than additivity, majority of heavy metals bring about synergistic reaction .The work presented in this thesis comprises lethal and sublethal toxicities of different salt forms of copper and silver on the brown mussel Perna indica. during the present investigation sublethal concentrations of copper and silver in their dent effects on survival, oxygen consumption, filtration, accumulation and depuration on Perna indica. The results are presented under different sections to make the presentation meaningful . |
| Description: | Division of Marine Biology, Microbiology and Biochemistry, School of Marine Sciences, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3223 |
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| Dyuthi-T1197.pdf | (7.001Mb) |
| Abstract: | Asha M. R This thesis Entitled Toxicological effects of copper and mercury on the fish macerones gulio (hamiloton – buchanan).Chapter 1. In this chapter, a broad outline of heavy metal uptake, requirement of a suitable bio — monitoring organism, criteria for a standard test fish, and suitability of Macrones gulig for the toxicological study are given. Chapter 2. This chapter deals with the lethal toxicity bioassays to find the 96 hr LC 50 of copper and mercury for the fish Macrones gglig. The experimental results indicated that of the two metals tested, copper was more toxic than mercury.Chapter 3. The effect of copper and mercury on the haemoglobin, haematocrit, erythrocyte count, MCV, MCH and MCHC was studied.Chapter 4. The glycogen and protein contents of liver and muscle after exposure to copper and mercury were studied. There was a significant decrease of glycogen in the liver and muscle of metal treated fishes.Chapter 5. The histopathological changes of the tissues like liver, kidney and gill after exposure to copper and mercury were studied. |
| Description: | School of Marine Sciences, Department of Marinebiology, Microbiology and Biochemistry, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3035 |
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| Dyuthi-T1009.pdf | (3.102Mb) |
| URI: | http://dyuthi.cusat.ac.in/xmlui/purl/1898 |
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| Dyuthi-T0322.pdf | (9.305Mb) |
| Abstract: | The title of the study is ''Toxicology Literature: An Informetric Analysis".In the field of Toxicology, the interdisciplinary research resulted in 'information fragmentation' of the basic subject to environmental, medical and economic toxicology. The interest in collaborative research resulted in the transdisciplinary growth of Toxicology which ultimately resulted in the scatter of literature.For the purpose of present study Toxicology is defined as the physical and chemical aspects of all poisons affecting environmental, economical and medical aspects of human life. Informetrics is "the use and development of a variety of measures to study and analyse several properties of information in general and documents in particular."The present study fled light on the main fields of Toxicology research as well as the important primary journals through which the results are being published. The authorshippattern, subject-wise scatter, country-wise, language-wise and growth pattern, self-citation, bibliographic coupling of the journals were studied. The study will be of great use in forrnulatinq the acquisition policy of documents in a library. The present study is useful in identifying obsolate journals so that they can be discarded from the collection |
| Description: | Department of Computer Science, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3143 |
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| Dyuthi-T1117.pdf | (5.503Mb) |
| Abstract: | In this thesis T-policy is implemented to the inventory system with random lead time and also repair in the reliability of k-out-of-n system. Inventory system may be considered as the system of keeping records of the amounts of commodities in stock. Reliability is defined as the ability of an entity to perform a required function under given conditions for a given time interval. It is measured by the probability that an entity E can perform a required function under given conditions for the time interval. In this thesis considered k-out-of-n system with repair and two modes of service under T-policy. In this case first server is available always and second server is activated on elapse of T time units. The lead time is exponentially distributed with parameter and T is exponentially distributed with parameter from the epoch at which it was inactivated after completion of repair of all failed units in the previous cycle, or the moment n-k failed units accumulate. The repaired units are assumed to be as good as new. In this study , three different situations, ie; cold system, warm system and hot system. A k-out-of-n system is called cold, warm or hot according as the functional units do not fail, fail at a lower rate or fail at the same rate when system is shown as that when it is up. |
| URI: | http://dyuthi.cusat.ac.in/purl/41 |
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| Dyuthi-T0308.pdf | (3.217Mb) |
| Abstract: | This thesis Entitled Trace metal speciation in the cochin estuary.Natural waters provide a favourable environment for speciation studies because of the prevailing variable chemical matrix and the variety of metal forms which may exist there.An estuary is a mixing zone of riverine and oceanic waters with widely varying compositions where end members interact both physically and chemically. The trace element chemistry in the estuarine environment has been an area of considerable research in the past decades. The trace metal distribution in the Cochin estuary is considerably influenced by the tropical features of the location and by human activities. The lower Periyar river and the Cochin estuary have been particularly selected for this investigation in view of the impact of trace metals on the estuarine ecosystem as well as in attempt quantify the phenomenon of metal speciation in the waters of a tropical coastal plain waterbody. If the concentration in the water media is very low, then, many of the fractions that could be estimated by speciation schemes for metals will fall below the detection limits, a factor which is undesirable.The study would also delineate the features of metal speciation which modify the chemical regime of ionic elements that traverse natural boundaries in aquatic environments, especally in those tropical areas prone to multivariate geographical settings. |
| Description: | Chemical Oceanography Division, School of Marine Sciences, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3117 |
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| Dyuthi-T1091.pdf | (4.663Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/1850 |
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| Dyuthi-T0320.pdf | (8.306Mb) |
| Abstract: | There are various studies conducted on transformational leadership and learning organization. The term gets more importance in current scenario as the technological advancement and many other factors made organization unsustainable without learning culture. The objective of this study was to identify relationship between transformational leadership and learning organizations. The study was conducted in 27 organizations inside Kerala and the tools used for the study are Multifactor leadership questionnaire (MLQ) 21 items by Bernad M Bass and B J Avolio and the Dimensions of learning organizations questionnaire (DLOQ) 43 items by Watkins and Marsick. The study has used confirmatory factor analysis, one way ANOVA, Pearson correlation analysis and Canonical discriminant function analysis for deriving the results. The result of this research proves that, there is a significant relationship between transformational leadership and learning organization. There is a significant positive impact of the factors of Transformational leadership i.e. idealized influence, inspirational motivation, intellectual stimulation, individual consideration, contingent reward, management by exception and laissez faire leadership in discriminating high, medium and low learning organization. |
| URI: | http://dyuthi.cusat.ac.in/purl/5261 |
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| Dyuthi T-2297.pdf | (2.291Mb) |
| Abstract: | Catalysis is a mature field with extensive practical applications in today's society.indeed,the catalysis of petroleum refining,fine chemical synthesis and emission control demands the production of catalysts in bulk quantities.Future improvement of these well established processes is likely to be incremental.On the other hand,the continuous demand for new products will require additional novel and innovative processes.The need for pollution abatement and prevention also imposes new demands on catalysis, and new processes are periodically advanced for the control of emission of gases as well as for remediation processes such as the cleaning of underground waters. The number of problems where catalysis can have a big impact is constantly growing.In general,science stimulated by the technology has enriched the field of catalysis in a way that has had broad and lasting value.The thesis"Transition metal and rare earth metal modified sol-gel titania: a versatile catalyst for organic transformations" accounts the preparation and characterization studies of both transition metals and rare earth metals modified sol-gel titania and its applications in industrially useful organic reactions. |
| Description: | Department of Applied Chemistry, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/2376 |
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| Dyuthi-T0648.pdf | (13.53Mb) |
| Abstract: | Thiosemicarbazones have recently attracted considerable attention due to their ability to form tridentate chelates with transition metal ions through either two nitrogen and sulfur atoms, N–N–S or oxygen, nitrogen and sulfur atoms, O–N–S. Considerable interest in thiosemicarbazones and their transition metal complexes has also grown in the areas of biology and chemistry due to biological activities such as antitumoral, fungicidal, bactericidal, antiviral and nonlinear optical properties. They have been used for metal analyses, for device applications related to telecommunications, optical computing, storage and information processing.The versatile applications of metal complexes of thiosemicarbazones in various fields prompted us to synthesize the tridentate NNS-donor thiosemicarbazones and their metal complexes. As a part of our studies on transition metal complexes with these ligands, the researcher undertook the current work with the following objectives. 1. To synthesize and physico-chemically characterize the following thiosemicarbazone ligands: a. Di-2-pyridyl ketone-N(4)-methyl thiosemicarbazone (HDpyMeTsc) b. Di-2-pyridyl ketone-N(4)-ethyl thiosemicarbazone (HDpyETsc) 2. To synthesize oxovanadium(IV), manganese(II), nickel(II), copper(II), zinc(II) and cadmium(II) complexes using the synthesized thiosemicarbazones as principal ligands and some anionic coligands. 3. To study the coordination modes of the ligands in metal complexes by using different physicochemical methods like partial elemental analysis, thermogravimetry and by different spectroscopic techniques. 4. To establish the structure of compounds by single crystal XRD studies |
| Description: | Department of Applied Chemistry, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3267 |
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| Dyuthi-T1241.pdf | (4.892Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/5203 |
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| Dyuthi T-2238.pdf | (14.24Mb) |
| Abstract: | Schiff base complexes of transition metal ions have played a significant role in coordination chemistry.The convenient route of synthesis and thermal stability of Schiff base complexes have contributed significantly for their possible applications in catalysis,biology,medicine and photonics.Significant variations in cataltytic activity with structure and type are observed for these complexes.The thesis deals with synthsis and characterization of transition metal complexes of quinoxaline based Schiff base ligands and their catalytic activity study.The Schiff bases synthesized in the present study are quinoxaline-2-carboxalidine-2-amino-5-methylphenol,3-hydroxyquinoxaline-2-carboxalidine-2-amino-5-methylphenol,quinoxaline-2-aminothiophenol.They provide great structural diversity during complexation.To the best of our knowledge, the transition metal complexes of quinoxaline based Schiff bases are poorly utilised in academic and industrial research. |
| Description: | Dept.of Applied Chemistry,Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/2364 |
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| Dyuthi-T0636.pdf | (3.783Mb) |
| Abstract: | Metallo-organic chemistry,incorporating the frontiers of both inorganic and organic chemical aspects,is a topic of utility concern.The first exploration of coordinated metal complexes dates back to the ninettenth century,during the days of Alfred Werner.Thereafter,inorganic chemistry witnessed a great outflow of coordination compounds,with unique structural characteristics and diverse applicatons.The diversity in structures exhibited by the coordination complexes of multidentate ligands have led to their usage as sensors,models for enzyme mimetic centers,medicines etc.The liganda chosen are of prime importance in determining the properties of coordination compounds.Schiff bases are compounds obtained by the condensation of an aidehyde or ketone with an amine.The chemical properties of Schiff bases and their complexes are widely explored in recent years owing to their pharmacological activity,their catalytic activities and so on.On the other hand pseudohalides like azide and thiocyanate are versatile candidates for the construction of dimeric or polymeric complexes having excellent properties and diverse applications.So a combination of the Schiff bases and the pseudohalogens for the synthesis of metal complexes can bring about interesting results.An attempt into this area is the besis of this Ph.D theis. |
| Description: | Department of Applied Chemistry, Cochln University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/2543 |
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| Dyuthi-T0687.pdf | (10.30Mb) |
| Abstract: | Coordination chemistry of pentadentate 2,6-diacetylpyridine bis(thiosemicarbazone) Schiff base ligands has been intensively studied due to the versatility of the molecular chain in order to obtain very different geometries as well as their broad therapeutic activity. Metal complexes of thiosemicarbazone with aldehydes and ketones have been widely reported. But there have been fewer reports on potential pentadentate bis(thiosemicarbazones) formed from 2,6-diacetylpyridine. Keeping these in view, we have synthesized four bis(thiosemicarbazone) systems with 2,6-diacetylpyridine. In the present work, the chelating behavior of bis(thiosemicarbazones) are studied, with the aim of investigating the influence of coordination exerts on their conformation and or configuration, in connection with the nature of the metal and of the counter ion. The selection of the 2,6-diacetylpyridine as the ketonic part was based on its capability to form polynuclear complexes with different coordination number. The doubled armed bis(thiosemicarbazones) can coordinate to a metal centre as dianionic ligand by losing its amide protons or it can coordinate as monoanionic ligand by losing its amide proton from one of the thiosemicarbazone moiety or it can also be coordinate as neutral ligand. Hence it is interesting to explore the coordinating capabilities of these ligands whether in neutral form or anionic form and to study the structural variations occurring in the ligands during complexation such as change in conformation. |
| Description: | Department of Applied Chemistry, Cochin university of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/2750 |
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| Dyuthi-T0775.pdf | (3.751Mb) |
| Abstract: | The unusual coordination modes of semicarbazones when bound to metals, the wide applications and structural diversity of metal complexes of semicarbazones provoked us to synthesize and characterize the tridentate ONO and NNO-donor semicarbazones and their transition metal complexes. This work is focused on the studies on complexes of three N4-phenylsemicarbazones synthesized by changing the carbonyl compounds. This work is concerned with the studies of two new semicarbazones, 2- formylpyridine-N4-phenylsemicarbazone (HL1) and 3-ethoxysalicylaldehyde- N4-phenylsemicarbazone (H2L2) and a reported semicarbazone 2-benzoylpyridine-N4-phenylsemicarbazone (HL3) [29]. The compositions of these semicarbazones were determined by the CHN analyses and IR, UV and NMR spectral studies were used for the characterization of these compounds. The molecular structure of 3-ethoxysalicylaldehyde-N4-phenylsemicarbazone (H2L2) was obtained by single crystal X-ray diffraction studies. Also, we have synthesized Cu(II), Cd(II), Zn(II) and Ni(II) complexes of these three semicarbazones. The complexes were characterized by various spectroscopic techniques, magnetic and conductivity studies. We could isolate single crystals of some complexes of all metals suitable for X-ray diffraction studies. This thesis is divided into six chapters. |
| Description: | Department of Applied Chemistry, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3261 |
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| Dyuthi-T1235.pdf | (10.04Mb) |
| Abstract: | The work embodied in this thesis was carried out by the author in the Department of Applied Chemistry, CUSAT, Kochi, during the period 2009-2012. The thesis is an introduction to our attempts to evaluate the coordination behavior of some compounds of our interest. The biological activities of semicarbazones and their metal complexes have been an active area of research during the past years because of their significant role in naturally occurring biological systems. Tridentate NNO and ONO semicarbazone systems formed from heterocyclic and aromatic carbonyl compounds and their transition metal complexes are wellauthenticated compounds in this field and their synthesis, crystal structures and spectral studies are well desirable. Hence, we decided to develop a research program aimed at the syntheses, crystal structures and spectral studies of new N4- phenylsemicarbazones derived from 2-formylpyridine and 3-ethoxysalicylaldehyde and their transition metal complexes and new transition metal complexes of 2- benzoylpyridine-N4-phenylsemicarbazone. In addition to various physicochemical methods of analysis, single crystal X-ray diffraction studies were also used for the characterization of the complexes. |
| URI: | http://dyuthi.cusat.ac.in/purl/5113 |
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| Dyuthi-T 2178.pdf | (10.53Mb) |
| Abstract: | In the present work,the chelating behaviour of thiosemicarbazones of a heterocyclic diketone, 2,6-diacetylpyridine is studied,with the aim of investigating the influence coordination exerts on their conformation and /or configuration, in connection with the nature of the metal and of the counter ion.The various possibilities like unsubstitution,ring incorporation at terminal nitrogen and condensation of one of the ketone group alone have been tried for ligand selection.Mainly first row transition metals like manganese,iron,nickel,copper,zinc and cadmium are studied.Metals like cobalt also were studied but could not result in fruitful isolation of the compound due to solubility problems.Different spectroscopic and characterization techniques have been utilized to reveal the nature of the metal and the ligands in coordinated metal complex. |
| Description: | Department of Applied Chemistry,Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/2790 |
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| Dyuthi-T0811.pdf | (6.089Mb) |
| Abstract: | Cashew is an important commodity traded across the continents and the world cashew industry is the livelihood of more than three million people worldwide, the majority of whom are womenfolk from the socially and economically backward community of the developing nations. Cashew tree was originally planted to prevent soil erosion and it was during the beginning of the 19th century that cashew kernels attained the status of a food item. Further, the cashew kernels attained the status of an international commodity with India exporting its first consignment of cashew kernels to U.S.A. in 1920. India was the first country to hit the world market with cashew as a commodity and it was she who pioneered cashew processing as an industry. For decades together India was enjoying a monopoly in the world cashew industry in the fields of raw nut production (cultivation), processing and the market share in the international trade. The liberalisation of international trade has brought in a big transition in the world of cashew. India started to benefit from the trade policy, that improved her supply positions of raw nuts from other producing countries, accelerated her growth in processing of raw nuts and exports of cashew kernels. On the other side, her domestic consumption started growing up that by the beginning of the new century, she emerged out as the world’s largest consumer of cashew kernels as well. |
| URI: | http://dyuthi.cusat.ac.in/purl/5106 |
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| Dyuthi-T 2172.pdf | (3.044Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/5164 |
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| Dyuthi-T2198.pdf | (9.513Mb) |
| Abstract: | The study documents the long-term trends in financial intermediation by the principal player in Kerala’s credit system i.e., banking. The process of financial intermediation by the banking system, involving mobilization of deposits from savers and disbursal of credit to investors, is considered to be crucial in the process of economic development. The objective of the study is to explore the interrelationship between financial intermediation and economic growth in Kerala. In order to pursue this objective, the study examine, the trends in intermediation by the banking system in Kerala over a long period, the trend and pattern of bank deposits and credit in the State and Kerala’s economic growth, the trend in the growth and performance of financial intermediaries like the All India Financial Institutions, the links between banking and economic variables, and the difference in the growth trends of banking and economic variables between Kerala and India and the probable reasons for the difference |
| URI: | http://dyuthi.cusat.ac.in/purl/100 |
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| Dyuthi-T0309.pdf | (6.923Mb) |
| Abstract: | The present work deals with the complexation of Schiff bases of aroylhydrazides with various transition metal ions. The hydrazone systems selected for study are capable of forming bridged polymeric structures which is one of the fascinating subjects in the crystal engineering of coordination polymers owing to their attractive new topologies and intriguing structural features. Complexation with metal ions like copper, manganese, vanadium, nickel, palladium, zinc and cadmium are tried. Various spectral techniques are employed for characterization. The structures of some complexes have been well established by single crystal X-ray diffraction studies.The work is presented in seven chapters and the last section deals with summary and conclusion. The studies reveal that the aroylhydrazone systems vary in their geometrical configuration depending on the substituents. The coordination modes of the ligands also differ upon chelating with metal ions. One of the hydrazone system selected for study proved that it could give rise to polymeric metal complexes. |
| Description: | Dept.of Applied Chemistry,Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/2992 |
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| Dyuthi-T0972.pdf | (9.698Mb) |
| Abstract: | This thesis entitled triterpenoids as biomarkers of mangrove organic matter in cochin estuarine system.Mangrove forests, known as rainforests of the sea are one of the most important coastal ecosystems in the world in terms of primary production and coastal protection.Estuaries, the important areas of world’s coastal zones link the carbon cycle of the oceans to the continents.Three mangrove ecosystems and three estuarine stations around Cochin region, southwest coast of India were selected for the present study. The thesis is divided into five chapters. Chapter 1 is the Introduction and it deals with the aim and scope of the present study. Chapter 2 is Materials and Methods. This chapter deals with the nature and general geographical features of the study area. It also contains the details of the sampling and analytical methodology.the present study. Chapter 3 is Geochemistry and it includes the seasonal and spatial variations of the geochemical parameters in the surface sediments.Chapter 4 is Biochemical Composition. It covers the biochemical composition of organic matter in the surface sediments to examine the quality and quantity of organic matter.Chapter 5, Triterpenoid Biomarkers in Sediments, characterize the organic matter in the sediments of the mangrove and estuarine ecosystems under study, to assess the possible sources with the help of triterpenoid biomarkers along with other lipid biomarkers. |
| Description: | Department of Chemical Oceanography, School of Marine Sciences, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3104 |
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| Dyuthi-T1078.pdf | (6.312Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/5211 |
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| Dyuthi T-2246.pdf | (13.88Mb) |
| Abstract: | The main purpose of the thesis is to improve the state of knowledge and understanding of the physical structure of the TMCS and its short range prediction. The present study principally addresses the fine structure, dynamics and microphysics of severe convective storms.The structure and dynamics of the Tropical cloud clusters over Indian region is not well understood. The observational cases discussed in the thesis are limited to the temperature and humidity observations. We propose a mesoscale observational network along with all the available Doppler radars and other conventional and non—conventional observations. Simultaneous observations with DWR, VHF and UHF radars of the same cloud system will provide new insight into the dynamics and microphysics of the clouds. More cases have to be studied in detail to obtain climatology of the storm type passing over tropical Indian region. These observational data sets provide wide variety of information to be assimilated to the mesoscale data assimilation system and can be used to force CSRM.The gravity wave generation and stratosphere troposphere exchange (STE) processes associated with convection gained a great deal of attention to modem science and meteorologist. Round the clock observations using VHF and UHF radars along with supplementary data sets like DWR, satellite, GPS/Radiosondes, meteorological rockets and aircrafl observations is needed to explore the role of convection and associated energetics in detail. |
| Description: | Department of Atmospheric Sciences, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/2985 |
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| Dyuthi-T0965.pdf | (30.03Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/5214 |
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| Dyuthi T-2249.pdf | (6.078Mb) |
| Abstract: | The present work is mainly concentrated on setting up a NIR tunable diode laser absorption (TDLA) spectrometer for high-resolution molecular spectroscopic studies. For successfully recording the high-resolution tunable diode laser spectrum, various experimental considerations are to be taken into account like the setup should be free from mechanical vibrations, sample should be kept at a low pressure, laser should be in a single mode operation etc. The present experimental set up considers all these factors. It is to be mentioned here that the setting up of a high resolution NIR TDLA spectrometer is a novel experiment requiring much effort and patience. The analysis of near infrared (NIR) vibrational overtone spectra of some substituted benzene compounds using local mode model forms another part of the present work. An attempt is made to record the pulsed laser induced fluorescence/Raman spectra of some organic compounds. A Q-switched Nd:YAG laser is used as the excitation source. A TRIAX monochromator and CCD detector is used for the spectral recording. The observed fluorescence emission for carbon disulphide is centered at 680 nm; this is assigned as due to the n, p* transition. Aniline also shows a broad fluorescence emission centered at 725 nm, which is due to the p,p* transition. The pulsed laser Raman spectra of some organic compounds are also recorded using the same experimental setup. The calibration of the set up is done using the laser Raman spectra of carbon tetrachloride and carbon disulphide. The observed laser Raman spectra for aniline, o-chloroaniline and m-chlorotoluene show peaks characteristics of the aromatic ring in common and the characteristics peaks due to the substitutuent groups. Some new peaks corresponding to low-lying vibrations of these molecules are also assigned |
| URI: | http://dyuthi.cusat.ac.in/purl/998 |
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| Dyuthi-T0314.pdf | (3.460Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/5486 |
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| Dyuthi T-2533.pdf | (32.06Mb) |
| Abstract: | Ultrasonic is a good tool to investigate the elastic properties of crystals. It enables one to determine all the elastic constants, Poisson’s ratios, volume compressibility and bulk modulus of crystals from velocity measurements. It also enables one to demonstrate the anisotropy of elastic properties by plotting sections of the surfaces of phase velocity, slowness, group velocity, Young’s modulus and linear compressibility along the a-b, b-c and a-c planes. They also help one to understand more about phonon amplification and help to interpret various phenomena associated with ultrasonic wave propagation, thermal conductivity, phonon transport etc. Study of nonlinear optical crystals is very important from an application point of view. Hundreds of new NLO materials are synthesized to meet the requirements for various applications. Inorganic, organic and organometallic or semiorganic classes of compounds have been studied for several reasons. Semiorganic compounds have some advantages over their inorganic and inorganic counterparts with regard to their mechanical properties. High damage resistance, high melting point, good transparency and non-hygroscopy are some of the basic requirements for a material to be suitable for device fabrication. New NLO materials are being synthesized and investigation of the mechanical and elastic properties of these crystals is very important to test the suitability of these materials for technological applications |
| URI: | http://dyuthi.cusat.ac.in/purl/997 |
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| Dyuthi-T0313.pdf | (2.776Mb) |
| Abstract: | The thesis investigated the elastic properties and phase transitions in selected mixed sulphate crystals – Lithium Hydrazinium Sulphate [LiN2H2SO4], Lithium Ammonium Sulphate [LiNH4SO4] and Lithium Potassium Sulphate [LiKSO4] – using ultrasonic technique. The pulse echo overlap technique has been used for measuring ultrasonic velocity and its dependence on temperature along different directions with waves of longitudinal and transverse polarizations. Two major numerical techniques and the corresponding computer programs developed as part of present work are presented in this thesis. All the 9 elastic constants of LHS are determined accurately from ultrasonic measurements and applying misorientation correction refines the constants. Ultrasonic measurements are performed in LAS to determine the elastic constants and to study the low temperature phase transitions. Temperature variation studies of elastic constant of LAS are performed for 6 different modes of propagation for heating and cooling at low temperatures. All the 5 independent elastic constants of LPS is determined using ultrasonic measurements. It is concluded that LPS crystal does not undergo a phase transition near this temperature. A comparison of the three crystals studied shows that LPS has maximum number of phase transitions and LHS has the least number. It is interesting to note that LPS has the simplest formula unit among the three. There is considerable scope for the future work on these crystals and others belonging to the sulphate family. |
| URI: | http://dyuthi.cusat.ac.in/purl/781 |
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| Dyuthi-T0311.pdf | (2.756Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/5423 |
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| Dyuthi T-2464.pdf | (3.869Mb) |
| Abstract: | Underwater target localization and tracking attracts tremendous research interest due to various impediments to the estimation task caused by the noisy ocean environment. This thesis envisages the implementation of a prototype automated system for underwater target localization, tracking and classification using passive listening buoy systems and target identification techniques. An autonomous three buoy system has been developed and field trials have been conducted successfully. Inaccuracies in the localization results, due to changes in the environmental parameters, measurement errors and theoretical approximations are refined using the Kalman filter approach. Simulation studies have been conducted for the tracking of targets with different scenarios even under maneuvering situations. This system can as well be used for classifying the unknown targets by extracting the features of the noise emanations from the targets. |
| Description: | Department of Electronics, Cochin University of Science and Technology. |
| URI: | http://dyuthi.cusat.ac.in/purl/3928 |
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| Dyuthi-T1789.pdf | (4.814Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/5301 |
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| Dyuthi T-2337.pdf | (2.757Mb) |
| Abstract: | The thesis deals with a benchmark study of dissolved and sedimentary sulphur compounds which play prominent roles in the prevailing redox conditions in the selected sites of Cochin estuarine system. Sulphur and its analogues play prominent roles in estuarine biochemical processes. A complete knowledge on the sulphur involvement in these processes is restricted due to the lacking of data on the organic sulphur compounds. Sulphate and sulphide in surface and bottom water and Sulphate, acid volatile sulphide and total sulphur in sediments were studied and correlated to know their interrelations in determining the redox condition of the environment. It also characterises the sediments of the sites on the basis of total organic carbon: total sulphur ratio. The study had attempted to decrease the concentration levels of sulphur in the sedimentary environment by the application of a remedial measure. Knowledge of sulphur uptake by plants from prior literatures has prompted to use phytoremediation for decreasing the sulphur concentration. Phytoremediation is an emerging technology that uses plants to clean up or remediate contaminated soil, sludges, sediments, and ground water through contaminant removal, degradation or containment. The plant selected was wheat grass since earlier studies have shown that wheat grass is effective in remediating pollutants particularly trace metals. So reduction in the concentration of selected trace metals was also focussed. |
| Description: | Department of Chemical Oceanography, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/2409 |
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| Dyuthi-T0657.pdf | (10.36Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/5471 |
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| Dyuthi T-2512.pdf | (1.591Mb) |
| Abstract: | Studies in urban water supply system are few in the state of Kerala. It is a little researched area. In the case of water pricing a number of studies are available. In Kerala state, exception to Jacob John’s study on “Economics of Public Water Supply System”, which is a case study of Trivandrum Water Supply System in 1997, no exhaustive research work has so far come out in this field. loreover no indepth research study has come up, so far, relating to household ater demand analysis and the distribution system of urban piped water supply. he proposed study is first of its kind, which focuses on the distributional and Iailability problems of piped water supply in an urban centre in Kerala state. Hence there is a felt need for enquiring into the sufficiency of )table water supplied to people in urban areas and the efficiency maintained in roviding the scarce resource and preventing its misuse by the consumers. It is in llS backdrop that this study was undertaken and its empirical part was conducted |Calicut city in the state of Kerala. Study is confined to the water supply system ithe city of Calicut |
| Description: | Department of Applied Economics, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3834 |
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| Dyuthi-T1765.pdf | (4.747Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/5322 |
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| Dyuthi T-2358.pdf | (6.781Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/5313 |
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| Dyuthi T-2349.pdf | (9.652Mb) |
| Abstract: | Hindi |
| Description: | Department of Hindi, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/4774 |
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| Dyuthi-T1871.pdf | (5.465Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/5187 |
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| Dyuthi T-2222.pdf | (6.684Mb) |
| Abstract: | The increasing tempo of construction activity the world over creates heavy pressure on existing land space. The quest for new and competent site often points to the needs for improving existing sites, which are otherwise deemed unsuitable for adopting conventional foundations. This is accomplished by ground improvement methods, which are employed to improve the quality of soil incompetent in their natural state. Among the construction activities, a well-connected road network is one of the basic infrastructure requirements, which play a vital role for the fast and comfortable movement of inter- regional traffic in countries like India.One of the innovative ground improvement techniques practised all over the world is the use of geosynthetics, which include geotextiles, geomembranes, geogrids, etc . They offer the advantages such as space saving, enviromnental sensitivity, material availability, technical superiority, higher cost savings, less construction time, etc . Because of its fundamental properties, such as tensile strength, filtering and water permeability, a geotextile inserted between the base material and sub grade can function as reinforcement, a filter medium, a separation layer and as a drainage medium. Though polymeric geotextiles are used in abundant quantities, the use of natural geotextiles (like coir, jute, etc.) has yet to get momentum. This is primarily due to the lack of research work on natural geotextilcs for ground improvement, particularly in the areas of un paved roads. Coir geotextiles are best suited for low cost applications because of its availability at low prices compared to its synthetic counterparts. The proper utilisation of coir geotextilcs in various applications demands large quantities of the product, which in turn can create a boom in the coir industry. The present study aims at exploring the possibilities of utilising coir geotextiles for unpaved roads and embankments.The properties of coir geotextiles used have been evaluated. The properties studied include mass per unit area, puncture resistance, tensile strength, secant modulus, etc . The interfacial friction between soils and three types of coir geotextiles used was also evaluated. It was found that though the parameters evaluated for coir geotextiles have low values compared to polymeric geotextiles, the former are sufficient for use in unpaved roads and embankments. The frictional characteristics of coir geotextile - soil interfaces are extremely good and satisfy the condition set by the International Geosynthetic Society for varied applications.The performance of coir geotextiles reinforced subgrade was studied by conducting California Bearing Ratio (CBR) tests. Studies were made with coir geotextiles placed at different levels and also in multiple layers. The results have shown that the coir geotextile enhances the subgrade strength. A regression analysis was perfonned and a mathematical model was developed to predict the CBR of the coir geotextile reinforced subgrade soil as a function of the soil properties, coir geotextile properties, and placement depth of reinforcement.The effects of coir geotextiles on bearing capacity were studied by perfonning plate load tests in a test tan1e This helped to understand the functioning of geotextile as reinforcement in unpaved roads and embankments. The perfonnance of different types of coir geotextiles with respect to the placement depth in dry and saturated conditions was studied. The results revealed that the bearing capacity of coir-reinforced soil is increasing irrespective of the type of coir geotextiles and saturation condition.The rut behaviour of unreinforced and coir reinforced unpaved road sections were compared by conducting model static load tests in a test tank and also under repetitive loads in a wheel track test facility. The results showed that coir geotextiles could fulfill the functions as reinforcement and as a separator, both under static and repetitive loads. The rut depth was very much reduced whik placing coir geotextiles in between sub grade and sub base.In order to study the use of Coir geotextiles in improving the settlement characteristics, two types of prefabricated COlf geotextile vertical drains were developed and their time - settlement behaviour were studied. Three different dispositions were tried. It was found that the coir geotextile drains were very effective in reducing consolidation time due to radial drainage. The circular drains in triangular disposition gave maximum beneficial effect.In long run, the degradation of coir geotextile is expected, which results in a soil - fibre matrix. Hence, studies pertaining to strength and compressibility characteristics of soil - coir fibre composites were conducted. Experiments were done using coir fibres having different aspect ratios and in different proportions. The results revealed that the strength of the soil was increased by 150% to 200% when mixed with 2% of fibre having approximately 12mm length, at all compaction conditions. Also, the coefficient of consolidation increased and compression index decreased with the addition of coir fibre.Typical design charts were prepared for the design of coir geotextile reinforced unpaved roads. Some illustrative examples are also given. The results demonstrated that a considerable saving in subase / base thickness can he achieved with the use of eoir geotextiles, which in turn, would save large quantities of natural aggregates. |
| Description: | Division of Civil Engineering, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/2816 |
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| Dyuthi-T0836.pdf | (11.46Mb) |
| Abstract: | One of the objectives of the current investigation was to evaluate the effectiveness of Spirodela polyrhiza to remove heavy metals and other contaminants from the water samples collected from wetland sites of Eloor and Kannamaly under controlled conditions .The results obtained from the current study suggest that the test material S. polyrrhiza should be used in the biomonitoring and phytoremediation of municipal, agricultural and industrial effluents because of their simplicity, sensitivity and cost-effectiveness. The study throws light on the potential of this plant which can be used as an assessment tool in two diverse wetland in Ernakulum district. The results show the usefulness of combining physicochemical analysis with bioassays as such approach ensures better understanding of the toxicity of chemical pollutants and their influence on plant health. The results shows the suitability of Spirodela plant for surface water quality assessment as all selected parameters showed consistency with respect to water samples collected over a 3-monitoring periods. Similarly the relationship between the change in exposure period (2, 4 and 8 days) with the parameters were also studied in detail. Spirodela are consistent test material as they are homogeneous plant material; due to predominantly vegetative reproduction. New fronds are formed by clonal propagation thus, producing a population of genetically homogeneous plants. The result is small variability between treated individuals. It has been observed that phytoremediation of water samples collected from Eloor and Kannamaly using the floating plant system is a predominant method which is economic to construct, requires little maintenance and eco friendly. |
| URI: | http://dyuthi.cusat.ac.in/purl/4983 |
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| Dyuthi-T2054.pdf | (12.49Mb) |
| Abstract: | The thesis consists of seven chapters. The first chapter is a general introduction on rice by-products, their composition and utilization at present. The different milling processes adopted in paddy and the major by-products obtained from these processes viz. rice husk, rice bran, rice bran oil and rice husk ash are described. The physical properties and chemical composition of the rice husk and its general uses are given in detail. The chemical composition of the rice bran and its separation from paddy is also included. The details of solvent extraction process used for obtaining rice bran oil and also its chemical constitution is discussed in this chapter. Also described is the preparation and the different uses of rice husk ash. A literature survey is also done on the utilization of rice by-products in rubber and plastics as on today. The scope and objectives of the present study is also included at the end of this chapter. |
| Description: | Department of Polymer Science and Rubber Technology, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3462 |
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| Dyuthi-T1439.pdf | (1.974Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/5206 |
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| Dyuthi T-2241.pdf | (11.07Mb) |
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