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An indirect electrochemical reduction and dyeing with indigo were carried out here to solve problems of low dye reduction rate and poor dyeing depth in the current electrochemical dyeing process.

Response surface analysis tests were performed to evaluate the effects of ferrous sulfate concentration, medium concentration, sodium hydroxide concentration and reduction time on the reduction efficiency of indirect electrochemical reduction of indigo.

The conditions obtained by design-expert optimization showed that the concentration of FeSO₄·7H₂O has the most significant effect on the reduction performance of dye liquor. Under the optimized electrochemical reduction dyeing process, the rate of dye reduction could be reached 91.21 per cent and the K/S value of indirect electrochemical dyeing of indigo can be achieved to 12.96, which is increased by about 9.56 per cent compared with that of Na₂S₂O₄ dyeing with the same color fastness basically.

The recyclability and biodegradability of the dye remain to be explored.

The strategy presented here can be developed to replace a substantial part of electrochemical dyeing with optimized product quality and reduced environmental pollution in denim production.

The strategy presented here can be developed to replace a substantial part of electrochemical dyeing with optimized product quality and reduced environmental pollution in denim production.

Application of the Fe(II)-DGS-Abal B complex media system in the indirect electrochemical reduction of indigo.

This paper aims to elucidate the geochemical characteristics of the hydrothermally altered rocks with gold mineralization and the elemental transfers in hydrothermal alteration hosted in alkaline complex in Hongshan area, Taihang Orogen, North China, and preliminarily discuss the relationship between the gold mineralization and the hydrothermal alteration.

Based on detailed field investigation, sampling and petrographical observation, major oxides and trace elements of nine rock samples are analyzed, and the method of mass balance equation is used in calculation of the elemental transfer.

Three alteration stages in the Hongshan area are identified, which are the early, main and late alterations. The early one is characteristic of extensive pyritization in the complex, which is related to the mantle-derived magmas and occurs before gold mineralization. The main one is characterized by developing a great deal of altered rock in fracture zones with the gain of many elements and the loss of a few elements. The late one is dominated by limonitization, that is limonite replacing the early pyrite or Fe₂O₃ replacing FeO in rocks. In the main alteration, the altered rocks obviously gain fluid component (LOI, i.e. loss on ignition) and elements such as V, As, Rb, Au, La, Ce and Nd and total rare earth elements (REEs). Elements such as K, Fe, Cu, Zn, Y, Mo, Sb, W, Re and U are gained in some altered rocks. Na and Sr are lost in all altered rocks, and Th and Bi are lost in some ones in the meantime. The following elements: Si, Mg, Mn, Ca, Li, Sc, Cr, Co, Ni, Zr, Ag, Ba and Hg show either gain or loss in different altered rocks. Au is notably enriched in the hydrothermal alteration. The elemental gain or loss in the altered rocks indicates that the main mineralization develops extensive de-alkalinization, local potassic metasomatism, silicification or desilicification.

Thin coatings are of great importance to minimize corrosion attack of steel in different environments. A review of recent work on electrodeposition and corrosion performance of Zn-Ni-based alloys for sacrificial corrosion protection of ferrous substrates is presented. The purpose of this study is to provide a systematic comparison of the corrosion resistances of Zn-Ni alloy coatings. The review contains key and outstanding comparisons of references for the period from 2007 to 2017. Binary and ternary Zn-Ni-based alloys were compared and contrasted to provide a good knowledge basis for selection of best coating system to steel substrates.

This article is a review article.

Zn-Ni-(X) alloys show great potential for replacing Cd metal in corrosion protection of steel substrates.

The research on plating of binary Zn-Ni alloys from aqueous electrolytes is now well advanced and these alloys show improved corrosion resistance compared to pure Zn. Pulse plated and compositionally modulated multilayer Zn-Ni alloy coatings showed enhanced corrosion properties compared to direct plated Zn-Ni coatings of similar composition.

The work on electrodeposition of Zn-Ni based alloys from ionic liquids is still scarce, yet these liquids show great promise in improving corrosion resistance and reducing coating thickness when compared to aqueous electrolytes. Advanced plating techniques in ionic liquids such as electromagnetic, compositionally modulated multilayer, pulse plating, ternary alloys and composites should be considered as these electrolytes avoid water chemistry and associated defects.

The purpose of this study to investigate the synthesis of new Cr(III), Fe(III), Ni(II) and Cu(II) Schiff base complexes by a simple technique (microwave technique). The evaluation of the prepared complexes as pigments as corrosion resistant was also explored.

The Schiff base complexes were prepared by using microwave method (green chemistry), and then, the physico-chemical requirements according to standards for the synthesised pigments were investigate.

The prepared complexes exhibit good physical, mechanical and corrosion properties as pigments in paint formulations.

The simple technique used for synthesis of metal complex pigments will significantly increase the cost saving for the manufacturing of such pigments category. Also, the used technique is considered a green method (eco-friendly), as there no organic solvent was used.

The evaluation of the prepared complex pigments as corrosion resistants was also studied.

It is a simple technique, green synthesis (no solvent used) is involved and high yield is obtained.

A plethora of publications have reported several cytotoxic effects associated with chronic consumption of thermoxidized palm oil. This research aims to investigate the effects of garlic and Aloe vera on liver function and hepatic cytoarchitecture in rats fed thermoxidized palm oil diet.

Thirty-five male albino Wistar rats weighing 150-180 g were used for this study. They were randomly assigned into five groups (n = 7): control, thermoxidized palm oil diet fed (TPO), TPO plus garlic juice (TPO + G), TPO plus Aloe gel (TPO + A) and TPO plus garlic/Aloe gel (TPO + G + A). The TPO diet was prepared by mixing 15 g of cooled thermoxidized palm oil with 85 g of rat feed. The juice and gel were orally administered at doses of 2.00 ml/kg and 19.12 ml/kg, respectively. After 3 months of feeding and administration, the animals were sacrificed using standard methods and blood collected via cardiac puncture for analysis.

Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase were significantly increased (p < 0.001) in the TPO group compared to the control. This increase was reduced (p < 0.001) in all the treated groups compared to TPO, with the greatest decrease (p < 0.001) seen in TPO + A. Total bilirubin was increased (p < 0.001) in the TPO group compared to the control, whereas there was a significant decrease (p < 0.001) in all the treated groups. Serum proteins and plasma fibrinogen were lowered (p < 0.001) in the TPO group compared to the control but increased progressively in all the treated groups. TPO induced prominent histopathological derangements of the liver tissues. However, there were marked improvements following treatment with garlic and Aloe vera.

The results obtained in this study have revealed that chronic consumption of thermoxidized palm oil is hazardous to health by inducing hepatotoxicity, as seen in increased ALT, AST and total and unconjugated bilirubin and decreased total protein. However, these debilitating effects were seen to be greatly ameliorated following garlic juice and Aloe vera gel administration. If these results are to be extrapolated to humans, then the chronic consumption of thermoxidized palm oil diet should be seriously discouraged.

In the production and overhaul of aero engines chemical and electrolytic surface treatment processes such as electrolytic degreasing, chemical and electrochemical etching, chemical descaling and chemical stripping of thermally sprayed coatings are used. In the course of some of these processes the heat resistant nickel and cobalt base alloys found in the “hot end” of the newer gas turbines are attacked. These superalloys have a common characteristic, namely, they are precipitation hardened. The alloying elements added for this purpose give rise to intermetallic compounds (carbides, nitrides, carbonitrides) which appear as inclusions of various shapes and sizes within the grain or at the grain boundaries. The conclusion from this work is that these intermetallics present as separate phases can be dissolved out by oxidative attack leaving pits. The separate processes and their objectives are detailed. It is shown in which process stages and in which solutions attack occurs. The inclusions have been analysed and the nature of the attack is illustrated. We conclude from this work, which has embraced seven nickel and cobalt base materials, that certain processes or process steps cannot be permitted on these alloys. For cleaning and etching alternative processes are given. For descaling a new compatible process was evaluated and will be discussed in a second report.

To study the changes occurring in lac‐polyvinyl butyral (PVB) resin blends at molecular levels on baking the blends at 200°C for different intervals of time. It was also to ascertain the changes in key physico‐chemical parameters of these blends, before and after applying thermal stress on these blends.

Films of lac‐PVB blends, applied on tin panels were baked at 200°C for different time intervals. The FTIR spectra of the blends were recorded using specular reflectance spectroscopic techniques. The results obtained were compared and reported. The blends were also tested for different physico‐chemical parameters such as scratch hardness, flexibility, adhesion, acid resistance, etc.

On baking the blends of lac‐PVB resin at 200°C for different time intervals; fragmentation reaction, that is breakdown of products into small molecules, takes place in lac‐PVB blends. Side products such as acetic acid emerge on baking the blends. Probably hydrolysis of oxirane ring also takes place leading to the release of free alcoholic groups. The lac‐PVB blends do not show any improvement in scratch hardness and are also not resistant to the action of acids. The blends made by lac‐PVB resin baked at 200°C do not seem to be compatible as no improvement in any of the physico‐chemical parameters was seen.

Mixtures of solvents were tried for dissolving the PVB resin. In most of the solvent mixtures, PVB resin forms big lumps and is not soluble so there is a need for universal solvent for dissolving the PVB resin. The spectral studies on lac‐PVB blends were conducted qualitatively, although desirable, quantitative studies could not be carried out, due to the inherent difficulties in handling the resins.

The parent resins in lac‐PVB blends (baked at 200°C) do not seem to be compatible with one another as there was no improvement in any of the physico‐chemical parameters of the lac‐PVB blends. For making lac‐PVB blends, low range of baking temperature may be tried.

In literature, there is not much evidence of making lac‐PVB blends. This paper is the first one in attempting to obtain and correlate FTIR spectra of the lac‐PVB blends with physico‐chemical changes of the blends. This paper also highlights the convenience of the method and the scope of sophisticated data analysis such as derivative spectrometry.

The purpose of this paper is to synthesize some new azobenzene dyestuffs clubbed with thiazolidinone moiety and their solicitation in dyeing polyester fabrics representing their antibacterial evaluation.

Herein, the authors report the synthesis of new thiazolidinone moiety after the coupling of diazotized 4-aminoacetophenone with resorcinol. The newly synthesized dyes were characterized by IR, elemental analysis, mass spectroscopy and proton nuclear magnetic resonance (1H NMR) spectral studies. The characteristics of dyeing of these dyestuffs were evaluated at optimum conditions. Concurrent with dyeing of polyester fabric for synthesized dyes with their antibacterial activity was estimated. Antimicrobial activity of the dyed fabrics at different concentrations was evaluated against gram-positive and gram-negative bacteria.

Synthesized azobenzene dyestuffs clubbed with thiazolidinone dyes were applied on polyester fabrics. It was remarked that the modified dyes exhibited better colourfastness properties. Furthermore, the synthesized dyes revealed antimicrobial activity against gram-positive and gram-negative bacteria.

The synthesized azobenzene dyes for polyester dyeing were not bore earlier.

The azobenzene dyes were accountable for giving improved colourfastness properties on polyester fabrics.

The synthesized azobenzene derivatives are sensibly expensive and applicable dyes accompanied with good antimicrobial and anticancer activities.

A common process could be affording textiles of colour and antibacterial assets. The newly synthesized dyes containing thiazolidinone moieties with azobenzene coupler showed interesting disperse colourant for polyester with good antibacterial activity.

The purpose of this paper is to study to minimize the self‐corrosion rate of Type 57S aluminium containing (97.7 per cent Al, 2 per cent Mn and 0.03 per cent Mg) in 2 M NaOH solution containing 0.2 M zinc oxide and 700 ppm of polyaniline.

The approach is used to measure weight loss and polarization measurements.

Results obtained show that as the amount of polyaniline is increased, the self‐corrosion rate of Alloy 57S aluminium decreases appreciably. Additionally, the open circuit potential is more in the case of 700 ppm level of polyaniline (−1.630 V) compare to 600 ppm level of polyaniline (−1.587 V). From this paper, it is also observed that the anodic polarization is greater than the cathodic polarization, thereby indicating that the overall corrosion of Alloy 57S 2 M NaOH containing 0.2 M ZnO and 700 ppm of polyaniline is under anodic control.

The results of the study clearly reveal that the overall corrosion of Alloy 57S aluminium in 2 M NaOH containing 0.2 M ZnO and 700 ppm of polyaniline is under anodic control. Hence, the 57S grade aluminium can be used as a potential candidate (anode) in alkaline batteries.

Tannic acid (TA) is one of the green corrosion inhibitors for mild steel; its anti-corrosive performance in alkaline water on mild steel when it is used together with polyaspartic acid (PASA) still has not been investigated. The purpose of this study is to develop an effective, biodegradable and environment-friendly novel corrosion inhibitor based on TA and PASA as an alternative to the conventional inorganic inhibitors for mild steel in decarbonised water, which is common in cooling systems.

Corrosion inhibition mechanism is investigated by electrochemical techniques such as polarisation measurements and electrochemical impedance spectroscopy, and results were evaluated to determine the optimum inhibitor concentration for industrial applications. Additionally, practice-like conditions are carried out in pilot plant studies to simulate the conditions in cooling systems. Thus, the efficiencies of the inhibitors are evaluated through both weight loss and linear polarisation resistance measurements. Moreover, the corrosion product is characterised by scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX) and Fourier-transform infrared spectroscopy (FTIR) analysis.

TA shows high inhibition efficiency especially towards pitting corrosion for mild steel in decarbonised water. PASA addition in the cooling systems improves the inhibition efficiency of TA, and at lower concentrations of TA + PASA, it is possible to obtained better inhibition efficiency than TA alone at higher inhibitor amounts, which is essential in economic and environmental aspect.

A blended inhibitor program including TA and PASA with suggested concentrations in this work can be used as an environmental friendly treatment concept for the mild steel corrosion inhibition at cooling systems.