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This paper aims to investigate the eco-friendly neodymium tartrate (NdTar) inhibitor for mild steel in sodium chloride (NaCl) solution.

The mild steel 1010 coupon was considered for the current study. Weight loss and the electrochemical methods were used to evaluate the inhibitory effects of neodymium chloride (NdCl₃) and NdTar on mild steel in NaCl solution. Scanning electron microscopy, energy-dispersive X-ray analysis and attenuated total reflectance-Fourier transform infrared spectroscopy measurements were carried out to study the morphology and composition of the film, nature of deposits and corrosion products formed in test media on the corroded steel, with the objective of further analyzing the observed behavior of the two inhibitors.

Of the two, NdTar performs better than NdCl₃ because it shields mild steel surfaces for longer. According to the results, when NdCl₃ is present in a corrosive solution, the protective film only comprises Nd/Fe oxide/hydroxide/carbonate. However, when neodymium is coupled with the tartrate group (an organic group) and then added to the NaCl solution, the inhibitor film comprises both bimetallic complexes (Fe-Tar-Nd) and metal oxide/hydroxide/carbonate, which results in a more compact film and has higher inhibition efficiency.

This study evaluated the combined effects of inorganic and organic inhibitors with those of an inorganic inhibitor used alone for mild steel in NaCl solution.

This study aims to dye silk with natural pigments extract of Coreopsis tinctoria, by treating the fabrics with appropriate mordant under suitable dyeing conditions, to achieve good dyeing depth, fastness and ultraviolet (UV) protection.

Firstly, single factor experiments were used to determine the basic dyeing conditions of Coreopsis tinctoria. The optimal process conditions for direct dyeing were determined through orthogonal experiments. After that, the dyeing with mordant was used. Based on the previously determined optimal process conditions, silk fabrics were dyed with different mordanting methods, with different mordants and mordant dosages. The dyeing results were compared, in terms of the K/S values of the dyed fabrics, to determine the most appropriate dyeing conditions with mordant.

The extract of Coreopsis tinctoria can dye silk fabrics satisfactorily. Good dyeing depth and fastness can be obtained by using suitable dyeing methods and dyeing conditions, especially when using the natural mordant pomegranate rind and the rare earth mordant neodymium oxide. The silk fabrics dyed with Coreopsis tinctoria have good UV resistance, which allows a desirable finishing effect to be achieved while dyeing, using a safe and environmentally friendly method.

The composition of Coreopsis tinctoria is complex, and the specific composition of colouring the silk fibre has not been determined. There are many factors that affect the dyeing experiment, which have an impact on the experimental results.

The results of this study may help expand the application of Coreopsis tinctoria beyond medicine.

To the best of the authors’ knowledge, this paper is the first report on dyeing silk with the extract of Coreopsis tinctoria achieving good dyeing results. Its depth of staining and staining fastness were satisfactory. Optimum dyeing method and dyeing conditions have been identified. The fabric dyed with Coreopsis tinctoria has good UV protection effect, which is conducive to improving the application value of the dyeing fabric. The findings help offer a new direction for the application of medicinal plants in the eco-friendly dyeing of silk.

The project Climbing Robot Cell for Fast and Flexible Manufacture of Large Scale Structures seeks to modernise and take into the future the technology of the manufacture of large fixed welded structures. It creates a transportable manufacturing cell consisting of a team of cooperating climbing robot work tools whose activities are coordinated and integrated through a central intelligence. The purpose of this paper is to present a wheeled robot, called NDT robot, designed for the real time inspection of long weld lines simultaneously with the welding process.

Neodymium permanent magnets are used for adhesion, which are capable of producing a maximum adhesion pressure of 4 × 104 Nm⁻² at a 20 mm air gap. The strong neodymium magnets give the robot a high payload carrying capability. The arrangement of the magnet array increases its performance at large air gaps so that the robot has excellent capability to overcome obstacles, such as weld caps. The design of the wheeled robot with two sections jointed by a hinge joint has the advantage of high speed and good manoeuvrability, as well as working on curved surfaces and transferring between angled adjoining surfaces.

The NDT robot has been developed with the capability of climbing on steel walls carrying the specified payload and the ability to overcome the obstacles. The robot is also able to climb on curved surfaces with excellent manoeuvrability, and transfer between angled adjoining surfaces.

The arrangement of the magnet array enables the robot to retain a strong holding force at big air gap, so that the ability of the robot to overcome obstacles and work on curvatures is strengthened. The two‐section design improves the robot's performance on curvatures and enables it to transfer between angled adjoining surfaces.

The purpose of this paper is to elaborate an algorithm and the software for the rotor structure optimization of the permanent magnet synchronous motor (PMSM) with a magnet composed of two materials made with the use of different technologies: sintered Neodymium magnets and powder dielectromagnets. To execute of optimization of selected motor structure using the non-deterministic procedure.

The mathematical model of the devices includes: the equation of the electromagnetic field, the electric circuit equations and equation of mechanical motion. The numerical implementation is based on finite element method and step-by-step algorithm. The genetic algorithm has been applied in the optimization procedures. The computer code has been developed.

The elaborated computer software has been applied for the optimization and design of PMSMs. The elaborated algorithm has been tested and a good convergence has been attained. The parameters of two optimal structures of PMSM motors have been compared.

The presented approach and computer software can be successfully applied to the design and optimization of different structure of PMSM with different type of rotors.

Guanidine stearate will function as a lubricant for melamine/formaldehyde resins (and guanamine/formaldehyde resins), and glyceryl monostearate can improve the mechanical properties of the former. Laurie acid can be applied to the production of high grade baking enemel resins in combination with melamine. Stearic acid can be used in the manufacture of melamine resins, e.g. by reaction with formaldehyde and butanol, to give resins for lacquers, and to yield moulding resins. Sodium myristate is usable as a chain transfer agent in the emulsion polymerisation of methyl methacrylate. Copolymerisation of methacrolein dibutyrate and methyl methacrylate has given resins that can be moulded or used in varnishes, and reaction products of stearic acid with methacrylic acid and neodymium oxide has given transparent optical resins. Cellulose laurate can produce extensibilities of nitrocellulose of the order of 100%, and cetyl acetate can act similarly in film, having little tendency to yellowing, but it has also little stability to exterior exposure. When ethylene glycol monmethyl ether acetyl ricinoleate is incorporated into nitrocellulose as a plasticizer, it gives films that are clear, tough and flexible. Stearic acid can act as a stabilizer for nitrocellulose. Lauryl phosphate has been applied as a catalyst in the modification of olefinic petroleum results, by reaction with acrylic resins, and distearyl pentaerythritol diphosphite can function as a heat stabilizer in petroleum resins.

The purpose of this paper is to explore, for the first time, the relationship between the prices of rare earth materials and economic growth. Renewable technologies and many high-demanded technologies need significant supplies of such materials.

The paper uses a panel of the six most significant rare earth producers around the globe, as well as certain panel methodologies.

The empirical analysis indicates the presence of a positive impact of such minerals prices on economic growth. Causality methodologies also indicate unidirectional causality between GDP and the prices of rare earth materials, with the causality running from these prices to economic growth. The findings survive a number of robustness checks.

The claim that natural resources are a curse that makes the countries worse off is not supported for the case of rare earth materials. The results are expected to be of high importance, because these particular rare earth materials are extensively used in a huge list of technological products with high demand and low costs, while they are hard to be replaced.

This paper aims to present an experimental investigation of improving the surface corrosion resistance of sintered neodymium-iron-boron (NdFeB) magnets by electrical discharge machining (EDM) in different dielectric fluids.

Scanning electron microscope and X-ray diffraction were used to analyze the surface morphology and chemical structure of recast layers formed by EDM using kerosene and distilled water as the dielectric fluids. Polarization scans and electrochemical impedance spectroscopy were applied to investigate the post-machining corrosion resistance.

The test results indicated that the recast layer produced during EDM had amorphous characteristics, and the newly formed amorphous structure could improve the corrosion resistance of the NdFeB material. The corrosion resistance of the recast layer formed in kerosene was better than that formed in distilled water.

Surface corrosion modification of sintered NdFeB magnets by means of electrical discharge with an ordinary copper electrode is proposed in this paper. The layer formed by EDM exhibits different behavior to that of the interior of the bulk material and improves the anti-corrosion performance of NdFeB magnets.