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The purpose of this paper is to investigate the synthesis of calcium-based group of mixed metal oxide (MMO) pigments. The evaluation of these pigments as heat and corrosion resistant was also explored.

Two simple synthesis techniques, namely, co-precipitation and solid-state calcination method, were used to synthesise nanosized MMO pigments. And then the physico-chemical requirements according to standards for the synthesised pigments are investigated.

The prepared MMO pigments were mainly in the single phase double oxide forms. The prepared oxides exhibited good heat (up to 600°C) and corrosion resistance properties (in 5 per cent NaCl for 500 h).

This paper investigates the physico-chemical properties of synthesised calcium-based group of MMO pigments. And then evaluate it as heat and corrosion resistant paints. The simple techniques used for synthesis of nanosized MMO pigments will significantly improve the research and development of pigments’ structure and performance.

Calcium-based MMO pigments can be used as heat and corrosion resistant pigments. The easy synthesis of the mixed oxide pigments will open the door for further vital special industrial uses and applications.

Low cost, simple techniques and using naturally abundant material can be used for mass production of some other low-cost nanosized materials.

The purpose of this paper is to study the patterns of formation of anti-corrosion properties, the development of compositions for pigments by using the method of co-precipitation and subsequent heat treatment.

To obtain co-precipitated hydroxides, aqueous solutions of salts were used. The conditions of synthesis varied according to the following parameters: the nature of the starting salts of metals; and the ratio of metal cations. The anticorrosive activity of the pigments was evaluated by the potentiodynamic method, by comparing the anodic and cathodic polarization curves, and calculated potentials and corrosion currents on the basis of regions of Tafel on curves. Polarization curves were obtained by using Potentiostat/Galvanostat/ZRA Gamry, which connected to the PC, and by using the program Gamry Framework. The measurement results were processed by using the method of simplex-lattice planning. X-ray diffractograms of pigments were recorded on a DRON – 2.0 diffractometer (monochromatic copper radiation with a nickel filter).

The paper deals with the results of research the dependence of colour characteristics and anticorrosion properties of synthesized compositions on their nature and composition. The presence of aluminium cations leads to the formation of solid solutions of ferrum and aluminium oxyhydroxides.

The main technological properties of pigments are determined by the anionic and cationic composition. Colour characteristics are determined by the cation-chromophore. The anti-corrosive properties of non-calcined pigments are determined to a greater extent by the presence of the formed hydroxyl ions and the composition of the compounds. The greatest protective effect is observed when using double compounds of metals, the dissociation constants of which differ significantly. The protective effect is mainly determined by the slowdown of the anode process. Anions containing aluminium atoms accelerate the corrosion processes.

It is essentially valuable to use simpler methods for making the protected pigment by inclusion of hematite in a transparent zirconium silicate crystal. The purpose of this paper is to compare solution combustion and co‐precipitation methods as two different routes for synthesis of zircon‐based coral pigment.

X‐ray diffraction, scanning electron microscopy and simultaneous thermal analysis were used to characterise and evaluate the precipitated zircon and Fe₂O₃ phases. The synthesised samples were incorporated into a suitable ceramic glaze and then their L*, a* and b* colour parameters were measured via Commission Internationale de I'Eclairage colorimetric method.

The results revealed that partial reduction of hematite (α‐Fe₂O₃) to maghemite (γ‐Fe₂O₃) destroyed the quality of the pigment obtained from the combustion processing method. Nevertheless, it is found that co‐precipitation would be an appropriate method for synthesis coral pigment.

It is found that the solution combustion method is not able to directly synthesise a zircon‐based coral pigment during combustion reaction. Furthermore, the presence of carbon has led to partial reduction of hematite resulting in unwanted crystalline maghemite phase. This reveals that solution combustion method is not suitable to obtain zircon‐based coral pigment.

The conventional method to synthesise ceramic pigments is a solid‐state reaction that requires high temperature and long processing time. The products are usually coarse and inhomogeneous so this method requires further processing like wet or dry milling in order to produce fine powders. Diffusion barrier in solid‐state processing prevents the control of the microstructure and the reactivity of the system. Soft‐chemical routes such as solution combustion and co‐precipitation methods are better choices to get finer powders and to achieve the desired phases at lower temperatures in shorter time as well.

Co‐precipitation synthesis of iron‐zircon coral pigment using sodium silicate (water glass) as Si source and its comparison with solution combustion method is valuable and has not been reported until now.

The purpose of this work is to study the patterns of pigment colour formation and to develop metal compositions for obtaining spinels using the precipitation and heat treatment methods.

Precursor materials were prepared using co-precipitation method. Phase composition of pigments were determined by X-ray diffraction. Colour of pigments was determined spectrophotometry. Modelling of colour formation was performed using simplex method. Planning in the future to carry out full synthesis of pigments of blue, red and yellow colours.

The paper deals with the results of theoretical and experimental research on the synthesis pigments of blue, red and yellow colours based on Fe-Co-Al-O spinel. The influence of the chromophore cation content and the heat treatment temperature on optical and colour characteristics of pigments were studied.

The resulting composition-property diagrams make it possible to evaluate the effect of chromophore cations and heat treatment on the colour formation for Fe₂O₃-Al₂O₃-CoO system. Crystal-phase composition of the pigments is installed and its relationship with the optical colour characteristics. That makes it possible carry out targeted synthesis of pigments blue, red and yellow colours in further. The phase composition of pigments and its relationship with optical and colour properties has been established thus enabling the directed synthesis of blue, red and yellow pigments.

The purpose of this paper is to focus on the removal of copper(II) ions from aqueous model salt solution by using chitosan-coated magnetite nanoparticles.

The chitosan-coated magnetite nanoparticles were characterized using X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy and thermogravimetric differential thermal analysis. The adsorption of Cu(II) by using magnetite nanoparticles as an adsorbent was investigated under different adsorption conditions. The parameters studied were contact time, adsorbent dose and initial concentrations.

The sorption capacities of prepared samples were studied for the removal of Cu²⁺ ions from aqueous model solutions with varying experimental conditions of the initial metal concentration, contact time and dosage. It is found that the removal percent of Cu²⁺ ions increases with an increase in initial metal concentration, contact time and amount of dosage.

Based on the obtained results, this study recommends that chitosan-coated magnetite nanoparticles can also be applied for removal of some heavy metal ions and/or organic compounds in aqueous solution. It is recommended that this study be shared with the polymer-based nanomaterial researchers, especially material science.

In this Chapter, cerium (III) oxide nanoparticles were prepared by co-precipitation method using hydrogen peroxide as the precipitant in slightly alkaline medium which is greener and environmentally suitable, cheap and best as compared to other conventional methods. Here, hydrogen peroxide acts as precipitating, reducing and stabilizing agents. Since studies worldwide reveal a very strong, significant positive association between air pollution and COVID-19 cases, hence, this environment-friendly synthesis process will prove to be most economically effective one to combat the COVID situation. The synthesized cerium (III) oxide nanoparticles were initially noted through visual color change from colorless pale yellow cerium (III) to light yellow cerium (IV). Moreover, the formation and size of cerium (III) oxide nanoparticles were evidenced by the X-ray diffraction, transmission electron microscopy and UV-VIS spectroscopy studies. The very high surface area and very small average crystallite sizes of these prepared cerium (III) oxide nanoparticles (5–20) nm in size is mainly responsible for their catalytic properties and hence can be effectively used for the removal of hazardous toxic pollutant gases such as carbon dioxide and sulfur dioxide from the environment with a view to combat the pollution within the environment to increase sustainability and also ensure a better, healthy and safe environment, particularly, in context of COVID in globalized world. This chapter, as its main objective, mainly focuses on utility of the nanotechnology and its beneficiary in creating a sustainable environment in economic world, particularly for gender development. Since the gas sensors will detect and reduce gaseous toxic pollutants from the environment, so lower the pollution greater will be sustainable environment development in terms of human development index and hence higher will be overall economic development in favor of Gender Development Index across world. However, as major findings, developing countries have been successful in maintaining a sustainable human development, in spite of higher Per Capita Income (PCI) growth, as compared to the role of least developing countries, with lower PCI in this global world, in favor of their respective gender development.

The purpose of this paper is to synthesize the manganese ferrite nanoparticle MnFe₂O₄ and to investigate the structure, size and to study the electronic and the magnetic properties of MnFe₂O₄ nanoparticles.

The co-precipitation method is used to synthesize the MnFe₂O₄. The structure and size were investigated by X-ray diffraction. The superconducting quantum interference device is used to determine the some magnetic ground. From theoretical investigation point of view self-consistent ab initio calculations, based on density functional theory approach using full potential linear augmented plane wave method, were performed to investigate both electronic and magnetic properties of the MnFe₂O₄. The high temperatures series expansion (HTSE) is used to study the magnetic properties of MnFe₂O₄.

The saturation magnetization, the coercivity and the transition temperature varied between 21-43 emu/g, 20-50 Oe and 571-630 K, respectively, have been studied. The gap energy of MnFe₂O₄ has been deduced. The critical temperature and the critical exponent have been obtained using HTSEs.

In the present work, the authors study the electronic and magnetic properties of MnFe₂O₄. The results obtained by the experiment and by ab initio calculations were used in HTSE as input to deduce other physical parameters.

The purpose of this paper is to study the process of coprecipitation of polyhydroxocomplexes of nickel and aluminum from solutions of nickel (Ni) (II) sulfate and aluminum (Al) (III) sulfate with caustic soda and to study the conversion process to nickel aluminate and to check its properties.

For the thermodynamic analysis of the precipitation process, the software package MEDUSA was used. The dependences of the electrical conductivity, pH and residual concentrations as functions of the OH/Me ratio were obtained. Using X-ray phase analysis, spectroscopic analysis and derivatographic analysis, the properties of the products obtained were studied. The effects of OH/Me ratio and molar ratio cation of reagents on the physicochemical properties of the products were analyzed.

The paper deals with the results of theoretical and experimental research on the synthesis pigments of blue and green colors based on Ni-Al spinel. The influence of the molar ratio cation content on optical and color characterise of pigments were studied.

The original complex method of studying the processes of co-precipitation of cations in the form of hydroxides is proposed. pH precipitation of aluminum hydroxide and nickel are different. It is interesting to study their co-precipitation. The resulting single-phase product is a precursor of nickel aluminate over a wide range of cation ratios. The dependences of the electrical conductivity, pH and residual concentrations as functions of the OH/Me ratio were obtained.

The spinel NiFe₂O₄ has been identified as being a potentially successful anti‐corrosion ceramic that can be used in aluminium electrolysis under molten salt corrosive conditions (970°C). The evaluation and fabrication processing of NiFe₂O₄ has been studied in this paper. According to the analysis and comparison of material properties, it has been concluded that fabrication technology for making anti‐corrosion electrode material would not be exceptionally difficult and therefore that the material has a strong potential for use in this service.