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The purpose of this paper is to use the bio-based resource as the starting material for the synthesis of azo dye. Cardanol is one of the most used bio-based resources for carrying out the synthesis of various compounds having numerous end applications. The study presents an attempt to develop an azo dye from Cardanol having end applications in pH-responsive dyes.

The cardanol was sulfonated to block the para position by which ortho positioned hydroxyl group after diazotization and coupling will provide necessary pH-sensitivity. The diazotization of two naphthalene derivatives, i.e. 1-naphthol-8-amino-3,6-disulfonic acid (H-acid) and 7-amino-4-hydroxy-2-naphthalene sulfonic acid (J-acid) was carried out using the standard practice, and the diazotized compounds were coupled with the sulfonated cardanol. The obtained dyes were characterized by Fourier transform infrared, nuclear magnetic resonance, carbon-hydrogen-nitrogen-sulfur analysis and hydroxyl value. The colour properties were checked using UV-vis spectrophotometry and density functional theory, while thermogravimetric analysis was used for the thermal degradation studies of both the dyes.

Water-soluble cardanol-based azo dyes were prepared successfully having good thermal stability, and the obtained results are being presented in this paper.

The originality lies between the use of cardanol as a bio-based resource for the synthesis of azo-dye and the obtained azo-dye has the pH-sensitivity.

In this study, the conditions of obtaining neutral calcium sulfonate which is added to engine oils as a detergent‐dispersant was studied. For this purpose, post‐dodecyl benzene sulfonic acid, obtained from post‐dodecyl benzene which remains as the bottom product during the production of dodecyl benzene sulfonate was used as the initial substance. Additionally, the reactor to be used in the production of neutral calcium sulfonate was designed and the amounts of spindle‐oil, toluene, raw sulfonic acid solution and Ca(OH)₂ used during neutralization were determined.

This paper aims to improve the permeability and antifouling of polysulfone (PSF) ultrafiltration membranes, the PSF matrix was modified by incorporating sulfonated polysulfone (SPSF).

Systematic investigations were conducted on the synergistic effects of a pore-forming agent, coagulation bath temperature and SPSF doping in the casting solution on blended ultrafiltration membranes. The chemical composition of the membranes was analyzed using Fourier transform infrared spectroscopy. The morphology and surface roughness of the membranes were characterized using scanning electron microscopy and atomic force microscopy. The hydrophilicity of the membrane surface was analyzed using a contact angle meter. The permeability and antifouling properties of the blended membranes were also investigated through filtration experiments.

The results indicated that the blended ultrafiltration membranes demonstrated an optimal overall performance when PVP-K30 content was 5.0 Wt.%, coagulation bath temperature was 30°C and SPSF content was 2.4 Wt.%. In comparison to a pure PSF ultrafiltration membrane, there was a significant increase in pure water flux (390.7 L·m⁻²·h⁻¹) by 2.2 times, while bovine serum albumin retention slightly decreased to 93.8%. In addition, the flux recovery rate improved by 2.1 times (71.4%) compared to that of the original PSF ultrafiltration membrane.

The method provided a simple and practical solution for improving the antifouling and permeability of PSF ultrafiltration membranes.

SPSF was anticipated to serve as an excellent modification additive for the preparation of ultrafiltration membranes with superior properties.

Zinc is one of the most important nonferrous metals and finds extensive use in metallic coatings. It is resistant to atmospheric attack and corrodes rapidly only in highly polluted air. It is resistant to most fresh waters but its resistance to sea water and to very soft water is lower. In many aerated hot waters, reversal of polarity between zinc and iron occurs at temperatures of 60°C or above. The corrosion products of zinc are readily soluble both in alkalis and acids and protect the metal surface only in neutral media. In neutral solutions, zinc is corroded mainly by oxygen depolarisation. The dissolution rate of zinc in acids is greatly affected by the over‐potential of hydrogen evolution at cathodic inclusions.

Sodium oleic sulfonate (SOS), polyoxyethylene (20) sorbitan monooleate (Tween 80 or T₈₀) and their mixtures have been studied as acid corrosion inhibitors for mild steel in 1M HCl using adsorption and gravimetric techniques. All the data reveal that the compounds act as inhibitors in the acid environment. The adsorption and inhibition efficiency are discussed as a function of the concentration and the nature of mixing the two surfactants. T₈₀ + α_SOS mixtures show a better inhibition effect than SOS + α_T80, that increases with the value of α_SOS. The interaction and synergism of the investigated mixtures are studied by calculating the interaction parameters (β) and the degree of synergism (S) from surface tension‐concentration and corrosion data. The degree of synergism for T₈₀ + α_SOS is higher than that of SOS + α_T80. This is believed to be due to the presence of the small amount of the co‐surfactant SOS which serves as an anchor molecule for the nonionic molecules.

This paper aims to demonstrate the functionalization of polyamide parts made by selective laser sintering (SLS) for application as substrates for chemical analysis by surface-enhanced Raman scattering (SERS).

Fabrication of Nylon 12 (Duraform PA®) samples using two laser power levels and deposition of a layer of gold-coated zinc oxide nanostructures. Performance of these substrates in the detection of a known compound was tested by Raman spectroscopy.

The hydrothermal synthesis proved to be a good method for functionalizing the surface of polyamide parts made by the SLS process. By varying the synthesis temperature, ZnO nanoparticles and nanorods attached to the sample surfaces could be obtained. The degree of sample sintering had an effect on the growth of the nanostructures. The gold-coated functionalized surfaces enhanced the Raman signal from crystal violet by more than three orders of magnitude. ZnO nanorods grown on well-sintered SLS parts showed the best performance from the set of samples tested in this work.

ZnO nanostructures were grown directly on untreated surfaces of SLS-made polyamide. These substrates were used for chemical analysis by SERS.

This teaching case describes a born-global Indian enterprise in R&D that developed and leveraged knowledge-intensive business services in speciality chemicals, custom synthesis of genes and contract research co-evolving dynamic capabilities in partnership with multinationals from Europe and North America. The purpose of this case to explore how emerging market multinationals can leverage factor market strengths for niche positioning in industries generally populated by large players, in this case, the big Pharma companies.

The case describes how the international strategy of the company was rooted in the “Make in India” national policy. The risks and opportunities involved a “springboard” approach of gaining customer confidence in North America, Europe and Japan in incremental steps. Challenges concerned fostering a credible talent management eco-system where scientific spirit and business pathways were pursued around unknown and unfamiliar projects challenging resource-based views of the firm.

An interesting facet of this case is how the nexus of treaties with stakeholding constituents were configured and sustained for strategic management of intellectual capital and organizational knowledge.

The novelty of the case is in demonstrating how small EMNCs can leverage factor market advantages to become world leaders in niche segments. Another interesting feature is how such firms are organized around sustainability of shareholder value without profitability in their initial years.

This paper aims to investigate effect of porous polystyrene microspheres encapsulated inhibitor on the protection performance of epoxy resin coating.

Porous polystyrene (PS) microspheres were synthesized by soap-free emulsion polymerization. The morphology of microspheres was observed by scanning electron microscopy and transmission electron microscopy. Corrosion inhibitor benzotriazole was encapsulated into porous PS microspheres. The protection performance of epoxy resin coating with different contents of PS microspheres was tested by polarization curve.

The findings of electrochemical impedance spectroscopy and scanning vibrating electrode technique showed that addition of corrosion inhibitor to porous PS microspheres further improved the protection performance of the coatings.

Porous PS microspheres could be used as nanocontainer to encapsulate corrosion inhibitor.

Addition of porous PS microspheres with corrosion inhibitor improved the protection performance of the coatings.

The first major nickel alloy introduced to the industry, about 100 years ago, was a Ni‐Cu alloy 400. This alloy is still widely used in a variety of industries and will continue to be used in this current century. Over the past 100 years, especially in the last 50 years, improvements in alloy metallurgy, melting technology, and thermo‐mechanical processing, along with a better fundamental understanding of the role of various alloying elements has led to new nickel alloys. These have not only extended the range of usefulness of existing alloys by overcoming their limitations, but are reliable and cost‐effective and have opened new areas of applications. This paper briefly describes the various nickel alloy systems developed during the last 100 years and comments on what the future holds for the newer alloys developed in the last 20 years and on the competition faced by these alloys in the new millennium. High‐temperature alloys are not discussed in this paper.

This concluding part reviews the actions of inhibitors to acidic, ammonical, organic, atmospheric and miscellaneous product corrosion on aluminium. The comprehensive reference list is also concluded.