http://starc.stthomas.ac.in:8080/xmlui/xmlui/handle/123456789/239 Mon, 20 Apr 2026 14:23:43 GMT 2026-04-20T14:23:43Z http://starc.stthomas.ac.in:8080/xmlui/xmlui/handle/123456789/354 Physicochemical, electrochemical and quantum mechanical evaluations on organic and inorganic inhibitors for metal deterioration Binsi M Paulson; Joby Thomas K Mon, 01 Apr 2019 00:00:00 GMT http://starc.stthomas.ac.in:8080/xmlui/xmlui/handle/123456789/354 2019-04-01T00:00:00Z http://starc.stthomas.ac.in:8080/xmlui/xmlui/handle/123456789/327 Synthetic and natural organic inhibitors for metal corrosion physicochemical electrochemical morphological and quantum mechanical investigations Vidhya Thomas K; Joby Thomas K In recent years, the regulation of metal corrosion has been a great interest in the field of scientific research. The best and favourable method to reduce metal degradation is the usage of corrosion inhibitors. Natural products can be used as green corrosion inhibitors due to their ecofriendliness, low cost and availability. In the present work, plant extracts have been used as green corrosion inhibitors for mild steel in acid media. Microbial induced corrosion (MIC) is the destruction of a metal by the activity of living organisms either directly by enhancing the electrochemical reactions or indirectly because of their metabolic products. Natural products have some antimicrobial effects in situ. So, in this work synthetic inhibitors are used as MIC inhibitors. Schiff bases good example for synthetic organic compounds with potent corrosion inhibition activities. The thesis deals with physicochemical, electrochemical, morphological and quantum mechanical investigations on some selected natural corrosion inhibitors for mild steel in acid medium and on some synthetic inhibitors for microbial induced corrosion of mild steel in marine environment. The thesis spreads into nine main chapters. Chapter 1 deals with the introduction about corrosion, especially microbiologically influenced corrosion, mechanism of corrosion and corrosion control methods. This chapter also deals with the detailed literature, aim and scope of the work. Chapter 2 provides an account of the materials, methods and instruments used in this investigation. Chapter 3 brings out the corrosion inhibitory activity of lxora coccinea extract on mild steel in 1M HCl and 0.5M H2SO4 using various corrosion monitoring methods. The study revealed the excellent inhibition efficiency of the extract. Theoretical calculations and statistical analysis have also been performed. Chapter 4 depicts the corrosion inhibition studies of Croton persimilis extract on mild steel. Chapter 5 contains the results of the application of Tinospora cordifolia extract as a corrosion inhibitor for mild steel in 1M HCl and 0.5M H2SO4. The surface morphological studies have been performed using AFM to ascertain the adsorption performance of the inhibitor on the mild steel. Chapter 6 illustrates the similar studies on mild steel under the same conditions using Garcinia cambogia extract. Chapter 7 deals with inhibitive action of Clerodendrum infortunatum leaf and root extracts (CILE and CIRE) on mild steel in 1 M HCl and 0.5 M H2SO4 using various techniques. Chapter 8 is devoted to anticorrosion studies of Dioscorea bulbifera extract. The final chapter includes isolation and identification of bacterium from sea water and microbial induced corrosion studies using synthetic organic inhibitors derived from pyridine carbonyl compounds. Mon, 01 Nov 2021 00:00:00 GMT http://starc.stthomas.ac.in:8080/xmlui/xmlui/handle/123456789/327 2021-11-01T00:00:00Z http://starc.stthomas.ac.in:8080/xmlui/xmlui/handle/123456789/315 Multicomponent pesticide residue analysis on selected spices Ramesh Babu N; Joby Thomas K The use of chemical pesticides as crop protection agents is an indispensable feature of modern agriculture, which helps to ensure global food security. However, extended and indiscriminate use of these pesticides results in the accumulation of traces of these chemicals in the agricultural produce, termed as pesticide residues, which in turn cause harmful effects upon consumption of such produce. This makes pesticide residues a major food safety concern. Many countries across the world have issued increasingly stringent regulations of maximum residue limits (MRLs) for pesticide residues in various food commodities to ensure consumer protection. In this context, testing of pesticide residues in food is important to ensure compliance of food commodities with such regulations.Spices are considered difficult matrices to analyse because of their complex chemical composition, with significant concentrations of active compounds that contribute to their special properties like colour, flavour and aroma. These compounds can potentially interfere with analysis of pesticide residues. Spices are also very diverse, and belong to different classes like dried fruits, seeds, floral parts, roots etc. which are distinct from one another. It is practically difficult to use a single analytical method to cover all major classes of spices. Thus, modern analytical methods for spices need to be sufficiently general to aid easy implementation but also have to be fine-tuned with respect to different classes of spices to ensure analytical performance. Development of such methods using UPLC MS/MS and GC-MS/MS, covering different classes of spices, is documented in this thesis. Fri, 01 Jul 2022 00:00:00 GMT http://starc.stthomas.ac.in:8080/xmlui/xmlui/handle/123456789/315 2022-07-01T00:00:00Z http://starc.stthomas.ac.in:8080/xmlui/xmlui/handle/123456789/249 Structural, corrosion inhibition and biological investigations of schiff bases containing sulphur and their metal chelates Reeja Johnson; Joby Thomas K Sun, 01 Aug 2021 00:00:00 GMT http://starc.stthomas.ac.in:8080/xmlui/xmlui/handle/123456789/249 2021-08-01T00:00:00Z