Bøger af Susai Rajendran

Die Hemmwirkung von sechs Inhibitoren, nämlich Cetyltrimethylammoniumbromid, Natriumdodecylsulfat, Tween 80, Tween 60, Tween 20 und Triton X 100, bei der Bekämpfung der Korrosion von Kohlenstoffstahl in Brunnenwasser wurde mit der Gewichtsverlustmethode bewertet. Die Formulierung, die aus 200 ppm Tensiden und 50 ppm Zn2+ besteht, ergibt 96 %, 92 %, 90 %, 88 %, 85 % bzw. 84 % Hemmungseffektivität. Es besteht ein synergistischer Effekt zwischen Tensiden und Zn2+. Die Polarisationsstudie zeigt, dass das Tensid-Zn2+-System als gemischter Inhibitor funktioniert. Mechanistische Aspekte wurden durch Polarisations- und AC-Impedanzspektren untersucht. AC-Impedanzspektren zeigen, dass sich ein Schutzfilm auf der Metalloberfläche bildet. Aus den FTIR-Spektren geht hervor, dass der Schutzfilm aus einem Fe2+-Tensidkomplex und Zn(OH)2 besteht. Die Bildung der Monoschicht und die hydrophobe Natur wurden durch AFM-, FTIR- und Kontaktwinkelmessungen bestätigt. Mit steigendem Kontaktwinkel nimmt die Hydrophobie und damit die Korrosionsbeständigkeit zu. Die selbstorganisierenden Nanoschichten der Tenside bieten eine bessere Korrosionsschutzwirkung.

L'efficacité d'inhibition de six inhibiteurs, à savoir le bromure de cétyle triméthyle ammonium, le sulfate de sodium dodécyle, le Tween 80, le Tween 60, le Tween 20 et le Triton X 100, dans le contrôle de la corrosion de l'acier au carbone dans l'eau de puits a été évaluée par la méthode de la perte de poids. La formulation composée de 200 ppm d'agents de surface et de 50 ppm de Zn2+ donne respectivement 96 %, 92 %, 90 %, 88 %, 85 % et 84 % d'efficacité d'inhibition. Il existe un effet synergique entre les agents de surface et le Zn2+. L'étude de polarisation révèle que le système tensioactif-Zn2+ fonctionne comme un type d'inhibiteur mixte. Les aspects mécanistiques ont été étudiés par des spectres de polarisation et d'impédance CA. Les spectres d'impédance CA révèlent qu'un film protecteur se forme sur la surface du métal. Les spectres FTIR révèlent que le film protecteur est constitué d'un complexe Fe2+-surfactant et de Zn(OH)2. La formation d'une monocouche et la nature hydrophobe ont été confirmées par des mesures AFM, FTIR et de l'angle de contact. Plus la valeur de l'angle de contact augmente, plus l'hydrophobie s'accroît et plus la résistance à la corrosion augmente. Les nanocouches auto-assemblées des agents de surface offrent une meilleure efficacité d'inhibition de la corrosion.

Corrosion is a naturally occurring phenomenon. To limit the corrosion behavior of rebar steel in concrete (simulated concrete pore solution -SCPS), the use of inhibitors is a significant method. In the present study the following oxyanions were studied as corrosion inhibitors: Potassium permanganate (PP), Sodium molybdate (SM), TriSodium phosphate (TSP), Sodium Potassium Tartrate (SPT), Potassium dichromate (PDC) and Tri Sodium Citrate (TSC). They act as good corrosion inhibitors The mechanistic aspects of corrosion inhibition are based on the results obtained from weight loss method, the polarization study, AC impedance spectra measurements, UV visible absorption spectroscopy, Fluorescence spectroscopy, surface examination techniques like FT-IR spectroscopy, Cyclic Voltammetry, Scanning electron spectroscopy (SEM) and Energy dispersive analysis of X rays (EDAX) and Atomic force microscopy (AFM).The results the weight loss study show that the formulation consisting of 250 ppm of Inhibitor and 50 ppm Zn2+ has greater percentage of corrosion inhibition efficiency (IE), in controlling corrosion of rebar steel immersed in SCPS prepared in well water.

Tamil Nadu , a South Indian state, is famed for its Dravidian-style Hindu temples. In Madurai, Meenakshi Amman Temple has high ¿gopuram¿ towers ornamented with colourful figures. Recently there were many deaths due to dengue fever. Government of Tamil nadu is taking necessary steps to control dengue fever. One of the steps is telling about the importance of ¿NILAVEMBU KASAYAM¿ (Extract of Nilavambu) in the treatment of dengue fever. One of the eminent actors in Tamil nadu Sri Kamal Haasan requested his followers to distribute this extract only after being convinced the medicinal values of this extract. This created more awareness and significance of Nilavembu and Dengue. This motivated the authors to write about the origin of dengue fever, the mosquito, symptoms, treatment, after effects, the significance of nilavembu, its active principles and its medicinal values. This resulted in the publication of this book. Papaya leaves juice is also recommended for the treatment of Dengue fever. World Health Organization has taken necessary steps to control Dengue fever. Development of Immunity is the best way to combat Dengue fever. Food items which develop immunity in body are presented.

The present study deals with the corrosion behaviour of mild steel immersed in simulated concrete pore solution (SCPS) prepared in DD water in the presence of inhibitors such as Tri Sodium Citrate, Potassium Sodium Tartrate, N-Cetyl N,N,N-Trimethylammonium Bromide, Sodium Dodecyl Sulphate in the presence of Cl- ion. The corrosion resistance has been investigated by electrochemical and non-electrochemical methods. The order of IE of the inhibitors is as follows: TSC>SPT>CTAB>SDS. In order to investigate the nature of the protective film, UV-Visible Absorption Spectroscopy, Infrared Spectroscopy, Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM) and Fourier Transform-Infrared Spectroscopy (FTIR) has been used in the present study. The mechanistic aspects of corrosion inhibition are based on the classical weight loss method, the polarization study and different surface examination techniques.

This book discusses various aspects of galvanic corrosion, namely causes, consequences, methods of control, and case studies. It also reports research on the causes of corrosion of the sunken ship, including microbiologically influenced corrosion (MIC) and metallurgical failure.