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The purpose of this paper is to study the effect of temperature on Zn–Ni alloys in ChCl–Urea.

Based on cyclic voltammetry experiments, the deposition behavior and kinetics of the Zn–Ni alloy are studied. The nucleation process of the Zn–Ni alloy is studied in detail via chronoamperometry experiments. The effects of the deposition temperature on the microstructure, Ni content and phase composition of Zn–Ni alloy coatings are investigated via scanning electron microscopy and X-ray diffraction (XRD) combined with classical thermodynamics.

The results show that with increasing temperature, the reduction peak shifts toward a more positive electric potential, which is beneficial for the co-electric deposition process, and the diffusion coefficient is estimated. With increasing temperature, the nucleation process of the Zn–Ni alloy becomes a three-dimensional instantaneous nucleation, the typical kinetic parameters are determined using the standard 3D growth proliferation control model and the Gibbs free energy is estimated. The Zn–Ni alloy coatings are prepared via normal co-deposition. With increasing temperature, the degree of crystallinity increases, the coating gradually becomes uniform and compact and the XRD peak intensity increases.

The nucleation process of the Zn–Ni alloy at different temperatures is analyzed. The diffusion coefficient D and Gibbs free energy are calculated. The contribution of the three processes at different temperatures is analyzed. The effect of temperature on the morphology of the Zn–Ni alloy coatings is studied.

The purpose of this paper is to present the optimisation of protocols for the immersion coating of silver onto copper‐track printed circuit board (PCB) assemblies, using a novel class of ionic liquid and to show the implementation of the scale up process.

Various conditions (temperatures and silver concentrations) are studied individually under laboratory conditions and then optimised for a pilot scale demonstrator line that is used to process British Standard test coupons.

The use of these novel liquids for the immersion coating of silver produces silver dip coatings that are bright and even and which give solderability that is as good as the commercial aqueous, nitric acid based, electroless process without any solder‐mask interface etching.

The combined technology has been optimised for an immersion silver coating line. Further development work should be undertaken to tailor the technology for gold immersion coating of PCB assemblies.

The paper details a process in which no solder‐mask interface etching is observed; that does not require the use of strong inorganic acids or expensive catalysts to sustain deposition and which does not appear to be light sensitive in contrast to other processes.

Textile industry is considered to be one of the largest consumers of water. There needs to be an alternative for water in textile wet processing. Solvent dyeing can be an approach to replace the use of water in dyeing for water conservation.

In this study, the dyeing of polyester was carried out using conventional and solvent dyeing methods. The solvent used was non-aqueous, deep eutectic solvent (DES) prepared using choline chloride and urea. Dyeing parameters such as time, temperature and pH were optimized for a concentration of dye using the solvent and were compared with the conventional dyeing.

The prepared solvent was characterized in terms of Fourier-transform infrared resonance and ¹H and ¹³C nuclear magnetic resonance to analyze the reaction between choline chloride and urea. Dyeing performance in terms of K/S and fastness properties of dyed fabrics were evaluated and found to be at par against conventional dyeing.

Use of DES as a dyeing medium is a novel approach in the textile industry.

Dyeing of silk fabric was studied to increase dye uptake using eco-friendly glycerine based eutectic solvent (GES), which acts as a swelling agent.

The swelling behaviour of silk fabric in GES was analyzed using three-dimensional laser scanning microscope. Dyeing parameters such as time, temperature and GES concentration were optimized using design of experiments.

In total, 5.34 F-value and 0.0014 p-value of ANOVA represent that the model is significant. An optimized GES assisted dyeing was carried out with two different classes of dyes such as Acid Blue 281 and Acid Red 151 and further compared with that of conventional aqueous dyeing method.

At 70°C, silk fabric achieves desired colour strength after 35 min of dyeing (10 min lesser than conventional) using GES assisted dyeing method. % Dye exhaustion of GES assisted dye bath was carried out and found to be very good. Fastness properties such as washing, light and rubbing fastness of conventional and GES assisted dyed silk fabric showed comparable results.

This paper aims to investigate the electrolytic deposition of corrosion-resistant chromium coatings from a trivalent chromium plating bath based on deep eutectic solvent, a new generation of room temperature ionic liquids.

The electrolyte contained chromium (III) chloride, choline chloride and the additive of extra water. The surface morphology was estimated by means of SEM technique. The microstructure of as-deposited and annealed coatings was studied using X-ray diffraction method. The kinetics of the chromium electrodeposition and the corrosion electrochemical behavior of the coatings were investigated by cyclic voltammetry technique.

Chromium coatings with an amorphous type of microstructure are electroplated from this bath. Some carbon and oxygen are included in deposits obtained. The step-wise mechanism of the electrochemical reduction of Cr(III) ions to Cr(0) is detected. The current efficiency in this system sufficiently exceeds that typical of usual aqueous electrolytes. The coatings fabricated using plating bath based on deep eutectic solvent showed enhanced corrosion resistance in an acidic medium: there is no current peak of active dissolution in polarization curve and the corrosion potential shifts to more positive values as compared with “usual” chromium.

The electrodeposition of chromium coatings from an environmentally acceptable trivalent chromium electrolyte, a deep eutectic solvent containing chloride choline and extra water additive has been investigated for the first time.

This paper aims to propose a simple, effective and environmentally benign method for the synthesis of commercially important pigment copper phthalocyanine (PC) blue has been developed using deep eutectic solvent (DES).

DES prepared from choline chloride and urea is used as a reaction medium, as well as a source of ammonia. The design of the experiment and factorial design study has proved that the milder reaction conditions with high yields and reusability of DES are the key features of the present study.

The synthesized pigment is obtained at milder reaction conditions with excellent yield, which can be seen from the design of experiments done for the optimization of results.

The synthesized pigment was used as a colorant in epoxy-based paint and in screen ink, which gave satisfactory results with respect to color values and stability.

The screen ink prepared was formulated considering environmental aspects to avoid the use of solvents. Biodegradable components were added to the colorant to make the ink environment friendly.

Reactions occur at moderate temperatures without affecting the time factor, thus, it saves energy. A simple, effective and environmentally benign method for the synthesis of commercially important copper PC has been developed using DES. After the first batch, DES synthesized can be reused as a reaction medium where only a stoichiometric amount of urea is to be added. Simple work up, high yield and purity are achieved.