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This paper aims to investigate the effect of centrifugal disk finishing (CDF) technique on the surface and subsurface characteristics of the fused deposited modeling (FDM) parts in both theoretical and experimental aspects. From theoretical aspect, a novel theoretical model is developed as a function of layer deposition orientation, layer thickness, finishing working time, density ratio and hardness ratio to estimate the surface roughness profile of FDM part at different finishing conditions and finishing time intervals. Meanwhile, from the experimental aspect, an experimental campaign was performed under different mechanical and mechanical-chemical finishing conditions to verify the theoretical model and also assess the surface and subsurface characteristics of the polished parts.

The theoretical model commences with an approximation of surface profile of the FDM part through a sequence of parabola arcs, continues with the calculation of reference line and machined surface profile and leads to a formulation of surface roughness of as-printed and polished surface. In the experimental section, the FDM parts are polished under dry, pure water, 25% and 50% volumetric aqueous acetone solutions finishing conditions through CDF technique.

The comparison between experimental and theoretical results reveals 9% mean absolute error between theoretical and experimental results. Meanwhile, Rq reduction percentage of polished parts under dry, pure water, 25% and 50% aqueous acetone solutions are 66.1%, 54.5%, 56.9% and 67.2%, respectively. The scanning electron microscopy results reveal severe layer damage in dry finishing condition, while the application of 50% aqueous acetone as a polishing solution completely eliminates layer damage. Another promising finding was sticky material phenomenon on the surface of polished part under 25% finishing condition. The Shore hardness test illustrates that the surface hardness improvement of the polished parts under dry, pure water, 25% and 50% aqueous acetone solutions finishing conditions are 8.4%, 2.25%, 4.36% and 10.8%, respectively. The results also revealed that the dimension variation of polished parts under dry, pure water, 25% and 50% aqueous acetone solutions are 0.634%, 0.525%, 0.545% and 0.608%, respectively. The edge profile radius of the as-printed part is 134 µm, while the edge profiles radius of the polished parts under dry, pure water, 25% aqueous acetone solution and 50% aqueous acetone solution are 785.5 µm, 545.5 µm, 623.5 µm and 721.5 µm, respectively, at the polishing time of 720 min.

This paper fulfills an identified need to study the benefits of the mechanical-chemical polishing technique in comparison to mechanical and chemical polishing strategy of the FDM parts for the first time. Beside the experimental campaign, the novel analytical formulation of surface roughness as a function of mechanical properties of abrasive media and FDM part and finishing specifications provides a valuable insight in the case of material-removal processes.

This study aims to study electrochemically and by weight-loss experiments the effect of UAE Rhazya Stricta Decne extract on the corrosion inhibition of mild steel in 1.0 M HCl solution, which will serve researchers in the field of corrosion.

Weight loss measurements were carried out on mild steel specimens in 1.0 M HCl and in 1.0 M HCl containing various concentrations (ranging from 2.0 to 0.002 g/L.) of the UAE Rhazya Stricta Decne extract at temperatures ranging from 303 to 343 K.

The aqueous Rhazya Stricta Decne leaves extract was found to be a highly efficient inhibitor for mild steel in 1.0 M HCl solution, reaching about 90 per cent at 2.0 g/L and 303 K, a concentration considered to be very moderate. Even with one-tenth of that concentration, 0.2 g/L, an inhibition of about 82 per cent was obtained at 303 K. The rate of corrosion of the mild steel in 1.0 M HCl is a function of the concentration of the Rhazya Stricta Decne extract. This rate increases as the concentration of the Rhazya Stricta Decne extract is increased. The percentage of inhibition in the presence of this inhibitor was decreased with temperature which indicates that physical adsorption was the predominant inhibition mechanism because the quantity of adsorbed inhibitor decreases with increasing temperature.

This inhibitor could have application in industries, where HCl solutions at elevated temperatures are used to remove scale and salts from steel surfaces, such as acid cleaning of tankage and pipeline, and may render dismantling unnecessary.

This paper is intended to be added to the family of green corrosion inhibitors which are highly efficient and can be used in the area of corrosion prevention and control.

Aims to investigate the effect of chlorine on corrosion behaviours of stainless steels.

Very complicated thermodynamic calculations are needed to establish the E‐pH diagrams of commercial alloys, because they comprise of many elements. To avoid these complex calculations and facilitate corrosion prevention of AISI 316L stainless steel, the potentiodynamic method was used to construct the E‐pH diagram. The polarization curves were carefully experimented at the scan rate of 0.1 mV/s. The experimental conditions were aqueous solutions saturated with air (oxygen concentration 7.8‐8.5 ppm) containing chloride 0, 50, 500 and 5,000 ppm, pH 2, 4, 6, 8, 10 and 12, and at 25°C. The transpassive or pitting potential, the protection potential, the primary passive potential and the corrosion potential were determined from the polarization curves and plotted with respect to the pH of the solution. The ions in solution were investigated by qualitative chemical analysis and stated in the E‐pH diagrams.

The constructed E‐pH diagrams showed clearly the effect of chloride concentration in the tested conditions on the transpassive or pitting potential, the protection potential of AISI 316L stainless steels. The ion states after pitting corrosion were different at low and high pH. This may be useful information for further investigation of pitting corrosion mechanisms.

The E‐pH diagram was originally based on thermodynamic equilibrium. The potentiodynamic method was kinetically controlled and not in equilibrium. However, the experiments were kept at near stationary state as much as possible. The investigated E‐pH diagrams were limited for the solutions saturated with air containing chloride 0, 50, 500 and 5,000 ppm and at 25°C. The effects of temperature and other ions such as Fe³⁺, Mg²⁺, Ca²⁺, etc. on the transpassive or pitting potential, the protection potential, the primary passive potential and the corrosion potential should be further investigated, because natural water may contain those ions and is at high temperatures which could affect on the corrosion of AISI 316L stainless steels.

The investigated E‐pH diagrams may be applicable to avoid corrosion of AISI 316L stainless steels in similar conditions. The useful application may be for fields where natural water is not able to be treated, as is carried out in industry.

There have been several investigations on the effect of chloride on the corrosion behaviours of AISI 316L stainless steels. However, those investigations were carried out in different conditions. Very few experimental E‐pH diagrams of AISI 304L have been found, but not for AISI 316L stainless steels. The investigated diagrams showed also the ion states in pitting corrosion region which were influenced by pH. This may indicate the different pitting corrosion mechanism at different pH.

The aim of this research was to investigate the use of aqueous extracts of nettle plant (NE) as a green corrosion inhibitor of mild steel in hydrochloric acid solution.

The inhibition efficiency was investigated by weight loss measurements, potentiodynamic polarizations, electrochemical impedance spectroscopy, SEM observations and EDX analysis.

The inhibition efficiency increased with an increase in concentration of NE up to a critical concentration of 1.5×10−3 g · cm−3 where the highest inhibition efficiency of 97 percent was obtained. The adsorption of the inhibitor was spontaneous (reflected by the negative value of ΔG_ads0), supported the mechanism of physical adsorption and obeyed to the Langmuir adsorption isotherm. The inhibition action of the extracts was independent on the storage time; it could be conserved without any specific conditions of time and temperature.

The anticorrosion effect can be better understood when the active compound in the extracts is identified and what is the inhibition efficiency of one component in the presence of another in the mixture (synergetic or antagonist effects).

Nettle is a healthy plant, without particular toxicity that can find possible applications as environmentally friendly inhibitor of mild steel used as materials in food industry.

Aqueous nettle extracts were studied for the first time as corrosion inhibitor and its anticorrosion effect was proven by standard methods.

A corrosion inhibitor may be defined as a material which, when added in small amounts to a corrosive product or environment affecting a metal, effectively decreases its corrosion rate or perhaps prevents it altogether.

This study aims to synthesize Prussian blue {Fe^III₄[Fe^II(CN)₆]₃} pigment by reacting ferric chloride with different ferrocyanides through the same procedure. The influence of the ferrocyanide used on resulting pigment properties is studied.

Prussian blue is commonly synthesized by direct or indirect methods, through iron salt and ferrocyanide/ferricyanide reactions. In this study, the direct, single-step process was pursued by dropwise addition of the ferrocyanide into ferric chloride (both as aqueous solutions). Two batches – (K-PB) and (Na-PB) – were prepared by using potassium ferrocyanide and sodium ferrocyanide, respectively. The development of pigment was confirmed by an identification test and characterized by spectroscopic techniques. Pigment properties were determined, and light fastness was observed for acrylic emulsion films incorporating dispersed pigment.

The two pigments differed mainly in elemental detection owing to the dissimilar ferrocyanide being used; IR spectroscopy where only (Na-PB) showed peaks indicating water molecules; and bleeding tendency where (K-PB) was water soluble whereas (Na-PB) was not. The pigment exhibited remarkable blue colour and good bleeding resistance in several solvents and showed no fading in 24 h of light exposure though oil absorption values were high.

This article is a comparative study of Prussian blue pigment properties obtained using different ferrocyanides. The dissimilarity in the extent of water solubility will influence potential applications as a colourant in paints and inks. K-PB would be advantageous in aqueous formulations to confer a blue colour without any dispersing aid but unfavourable in systems where other coats are water-based due to their bleeding tendency.

This paper aims to propose a simple method for stabilizing silica-coated silver iodide (AgI/SiO₂) core-shell particles, of which a colloid solution functions as an X-ray contrast agent.

A colloid solution of AgI nanoparticles was prepared by mixing silver perchlorate and potassium iodide in water. The AgI/SiO₂ nanoparticles were fabricated by a sol-gel method using NaOH, H₂O and tetraethylorthosilicate in ethanol in the presence of AgI nanoparticles surface-modified with 3-mercaptopropyltrimethoxysilane.

The silica shells of AgI/SiO₂ particles were dissolved near the AgI nanoparticle surface, when they were washed by a process composed of centrifugation, removal of supernatant with decantation, addition of water as a washing solution and a shake with a vortex mixer. In contrast, the shells were not damaged by using ethanol as the washing solution, i.e. ethanol-washing. An X-ray photoelectron spectroscopy spectrum of the silica was changed after the ethanol-washing, which indicated that the ethanol-washing had an effect on the chemical bonds in silica. The effect also acted on the silica shells of AgI/SiO₂ particles, which did not damage the core-shell structure, i.e. controlled the dissolution of shell.

The paper demonstrates that the ethanol-washing is quite useful for stabilizing the core-shell structure composed of the silica shells.

Line widths are rapidly shrinking and the complexities of boards place increased demands on the resolution capabilities of the photoresists. A new technology is emerging that offers the user unparalleled resolution, a completely aqueous system, and complete, uniform, three‐dimensional coverage of the panel. The unique properties of this system result from the extraordinary method of application of the photoresist. Electrophoresis, or electrocoating, allows the deposition of a very thin, uniform, highly chemically resistant photoresist layer. Any exposed conductive surface, including scratches or other panel imperfections, are coated. The combination of a very thin layer and no cover sheet allows the printing of sub‐mil geometries without the need for a collimated light source. This new application offers the user high yields, both from the chemistry and in circuit yields. Even more so, the resolution capabilities offer opportunities beyond the limitations of dry film and other liquid resists. The photoresist no longer needs to be the gating factor in process capability.

Studere Corrosion has been described as a transformation process in which a metal passes from its elementary form to a combined condition. It includes wet and dry corrosion; the former requires an aqueous environment and the latter is oxidation. Deterioration of the metal due to physical causes is not called corrosion, but is known as erosion, galling, wear, etc, depending upon the material and the conditions. Corrosion is the result of the metal chemical or an electrochemical reaction with its environment. Sometimes the chemical reaction is accompanied by physical deterioration, as in fretting corrosion. It should be noted here that the term corrosion is only applied to metals; non‐metals rot, crack or erode. Also it should be appreciated that only ferrous metals can ‘rust’, i.e. form hydrous ferric oxides.

Cationic resin is widely used in decolouring of textile wastewaters. Tonnes of resin are used in sector, and disposal of resin is being a second waste problem. The purpose of this paper is to investigate the adsorption behaviour of the methylene blue cationic dye from aqueous solution on the cation exchanger Lewatit CNP80 to understand the regenerability of cation exchanger resin from textile wastewaters.

Cationic resin was used as an alternative low-cost adsorbent for removing methylene blue dye from textile wastewaters. The adsorption study was carried out in the batch mode. Batch adsorption studies were carried out to examine the effect of parameters such as methylene blue concentration, temperature, pH, resin dose, shaking speed and contact time.

It was observed that dye-removal capacity of resin was reached from 17 mgg⁻¹ to 19.4 mgg⁻¹ at 25 °C temperature, pH 5 in 15 min. At the appropriate range of parameters, it was observed that more than 98% removal efficiency was achieved for methylene blue dye, and also, this study was focussed on whether the resin regenerates. In regeneration studies, our purpose was to recover of non-regenerable exhausted cationic resin by NaOCl. Regeneration of Lewatit CNP80 was performed in five cycles. After regeneration, the authors tried to determine whether the adsorption capacity was affected by regeneration.

In this study, the authors focussed on regeneration studies. The aim is to find easy, low-cost regeneration agent. In conclusion, the authors found that NaOCl is eligible for regeneration studies. The exhausted resin was recovered by NaOCl, and the authors also tested 5th regeneration cycles. Sodium hypochlorite is not a common regeneration agent for adsorption studies. Generally, resin is regenerated by HCl or other regeneration agent products. As a result of that, operational cost was reduced, and the other thing that the authors want to emphasise is textile industry wastewater based high temperature; therefore, this regeneration study can easily work with textile industries.