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The purpose of this paper is to present the results of some corrosion inhibition studies of brass in 3N HNO3 by gemini surfactants.

Gemini surfactants namely: N‐trimethyl butane‐diyl‐1,2‐ethane‐bis‐ammonium bromide (BEAB), N‐hexane‐diyl‐1,2‐ethane‐bis‐ammonium bromide (HEAB), N‐dodecane‐diyl‐1,2‐ethane‐bis‐ammonium bromide (DDEAB) and N‐hexadecane‐diyl‐1,2‐ethane‐bis‐ammonium bromide (HDEAB) were synthesized in the laboratory and their influence has been investigated for controlling the dissolution of brass in 3N HNO3. Weight loss, potentiodynamic polarization and electrochemical impedance have been employed for the study. Weight loss experiments were performed as per standard method (ASTM, 1987). Potentiodynamic polarization studies were carried out using EG&G PARC potentiostat/galvanostat (model 173), universal programmer (model 175) and X‐Y recorder (model RE 0089) and impedance measurements were carried out with an EG&G PAR (model 5301 A) lock‐in‐amplifier, using an IBM computer.

The inhibition efficiency for all the gemini surfactants increases with increase in concentrations. The maximum inhibition efficiency of each inhibitor was achieved at 250 ppm concentration. The inhibition efficiency of all the inhibitors decreases on increasing the temperature from 30 to 50°C. The results of potentiodynamic polarization studies revealed that all the compounds were mixed type inhibitors and inhibit the corrosion of brass by blocking the active sites of the metal. The adsorption of the compounds on brass surface in 3N HNO3 has been found to obey the Langmuir adsorption isotherm.

The paper provides information regarding corrosion inhibition of brass in 3N HNO3, the mechanism of the inhibition on the basis of molecular structures of the inhibitors, activation energy and free energy of adsorption.

Stainless steel 316 was coated with CeO₂ and Y₂O₃ modified aluminide and titanium aluminide coatings. The coatings were prepared by the pack cementation method and the high temperature oxidation behaviour of the coatings was investigated in an atmosphere containing a limited supply of air. The performance of the coatings was studied by measuring oxidation kinetics, and by scanning electron microscopic techniques. The oxidation rates of these coatings were reduced in the presence of CeO₂ and Y₂O₃ due to better adherence of their oxide scales.

The purpose of the paper was to assess the functional properties vegetable gourds & the validated health claims so as to help the future researchers to locate the gaps. However, emphasizing on the scientifically available reports was required to make information available in a nutshell to the health-conscious consumers, as well as the researcher from the area of functional foods and nutrition.

The paper is a mini-review of scientific findings in different studies on gourd vegetables. The approach to information collection was finding the research gaps and potential areas for future work with a nutritional perspective.

Ash gourd, bitter gourd and bottle gourd have been extensively studied, and several health benefits and functional components have been reported, while ridge gourd, snake gourd and pointed gourd have been sparsely studied for their therapeutic benefits and the validation thereof; hence, there lies a scope for researchers.

The scarcity of scientific reports compared to the traditional usage and folkloric beliefs was a limitation.

Understanding the nutritional potential of gourd vegetables from scientific reports may influence both the work areas and consumers in the appropriate direction.