The harmful effects of various substances on the marine environment were reviewed by collecting and studying the relevant literature. Various sources for the pollution of marine environment were identified and the causes for the same are understood. Many of the pollutants that are let into the sea are directly or indirectly by human activities. Some of these substances are biodegradable, while some are not. Several laws and policies have been taken in preventing marine pollution at the national and international levels. Simulation of oil spills has been done by developing models in some parts of the world. The pollution off the shore is increasing at an alarming rate and to address this problem of pollution in the oceans is a difficult task, and a variety of approaches are urgently required. In this paper, the definition of coastal pollution, causes of coastal pollution, its impacts and preventive measures are discussed.

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In this study, thin films of polymer poly(methyl methacrylate) were prepared using a drop casting method. Two newly synthesized aldehyde derivatives, 2‐bromomalonaldehyde and 5,6‐dihydroimidazo[2,1‐b]thiazole‐2‐carbaldehyde, were used at different concentrations to dope the films. The prepared films were transparent and therefore studied for application in photonics. Optical characterization of the samples was carried out using different spectroscopy techniques. Absorption spectra for both samples were obtained using a UV–vis light spectrophotometer. Other significant optical parameters, such as refractive index, extinction coefficient, and band gap energies, were calculated from the absorption spectra. The effect of doping concentration on these parameters was studied. Emission spectra were obtained using a fluorescence spectrophotometer and the effect of doping was observed. Fourier transform infrared spectra of the doped films were obtained and compared with the pure compound to note changes in peak values and peak intensity. This present work studied the effect of doping on optical properties and examined the application of the samples for photonics.

With the advances in the plasma technology in several fields as waste management, space technology and medical applications, non-thermal plasmas have become popular. They replace the combustion fuels for stationary hall thrusters and require minimal voltage to sustain longer duration. Generally, non-reactive gases such as Xenon, Argon, Krypton in a pure or mixture form is used to generate plasma, in order to have overall better performance of the system. Hence, the study of these gases and its properties becomes very crucial for further improvement in any kind of application. Xenon has proven to be most efficient in Hall thruster as compared to the other gases, but its limited availability and high cost has led to the idea of replacing it with other gases that are in abundant. As the DC glow discharge is considered to be canonical problem of interest, the paper focuses on modelling and simulation of 1-D and 2-D. DC glow discharge tubes using Argon and Xenon as gases to generate plasma and study its properties. The trend in distribution of electron density, electron temperature and electric potential have shown little variation. However, the magnitude on electron density is slightly higher for Argon relative to Xenon for given operating conditions in 1-D simulation and in the case of 2-D simulation the diffusive nature in lateral direction has shown higher peak value for Xenon.

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