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Ni coating was electroplated on carbon steel substrate to protect carbon steel.

During electroplating, the ultrasonic irradiation (UI) (1 kHz) action was in situ used with different frequency. The influence of UI on the microstructure, mechanical and electrochemical performance of the coating was studied with scanning electron microscopy, X-ray diffraction, microhardness measurement, polarization curves and electrochemical impedance spectroscopy.

The results show that comparing that without UI imposition, UI during electroplating can refine the coating grain and decrease the micro-pores in the coating, resulting in improvement of the coating corrosion and hardness.

The imposition of UI action during electroplating Ni coating can remove intrinsic pores in the coating and compact the coating. The potential bimetallic cell between substrate and plating layer can be insulated to enhance the corrosion resistance of Ni coating. The imposition of UI action during electroplating Ni coating can refine Ni coating grain size and improve the coating haredness.

Application of rare earth (RE) salts as a corrosion inhibitor was first proposed by Goldie and McCarrol in 1984. They showed that, with the addition of 0.001 M of Ce(NO₃) or La(NO₃) to 3.5% NaCl solution, the inhibition efficiencies were 91 and 82% for carbon steel, respectively. The aim of this paper is to study the inhibition of a mixture of Ce and La cations on the corrosion prevention of St37 carbon steel in aerated NaCl solutions using weight loss, potentiodynamic polarization, open circuit potential and constant potential measurements.

In this study, St37 steel was used as an experimental sample. The applied inhibitor was a powder mixture of Ce and La oxides with the ratio of Ce/La = 2/1. Each gram of this powder was dissolved in 4 cc acetic acid because of their insolubility in water. Steel samples were polished with 120 to 800 grit SiC polishing papers, deoxidized in 15 per cent HCl, and then ultrasonically cleaned in ethanol. They were degreased in acetone and were dried in a flow of hot air.

It has been shown that a mixture of RE cations (Ce and La) can be used as a corrosion inhibitor for carbon steel in NaCl containing solutions. The optimum inhibitor concentration was found to be 500 ppm with a maximum inhibition efficiency of 76%. An increase in Cl⁻ ion concentration and a rise in temperature from room temperature to 70°C can have an adverse effect on corrosion inhibition efficiency.

The results obtained from various experiments indicated that the mixture of Ce and La cations could be considered as a suitable inhibitor for carbon steel in low to medium chloride‐containing solutions. Owing to their non‐toxic nature, they may be suitable to use in potable water pipelines.

The purpose of this study is to improve the corrosion resistance of the transmission towers by Zinc-aluminum-magnesium (Zn-Al-Mg) coatings doped with rare earths lanthanum (La) and cerium (Ce) (denoted as Zn-Al-Mg-Re) in Q345 steel.

The phase structure of Zn-Al-Mg-Re composite coatings has been determined by X-ray diffraction, whereas their surface morphology and cross-sectional microstructure as well as cross-sectional elemental composition have been analyzed by scanning electron microscopy and energy-dispersive spectrometry. Moreover, the corrosion resistance of Zn-Al-Mg-Re composite coatings has been evaluated by acetic acid accelerated salt spray test of copper strip.

Experimental results show that doping with La and Ce favors to tune the composition (along with the generation of new phase, such as LaAl₃ or Al₁₁Ce₃) and refine the microstructure of Zn-Al-Mg galvanizing coatings, thereby significantly improving the corrosion resistance of the coatings. Particularly, Zn-Al-Mg-Re with 0.15% (mass fraction) La exhibits the best corrosion resistance among the tested galvanizing coatings.

Zinc-aluminum-magnesium (Zn-Al-Mg) coatings doped with rare earths lanthanum (La) and cerium (Ce) (denoted as Zn-Al-Mg-Re) have been prepared on Q345 steel substrate by hot-dip galvanizing so as to improve the corrosion resistance of the transmission towers, and to understand the corrosion inhibition of the Zn-Al-Mg-Re coating.

This paper aims to study microstructure and high temperature tribological performance of hypo-eutectic CoCrWC hardfacing alloy (Stellite 12) deposited on steel substrate by plasma-transferred arc (PTA) welding technique.

Microstructural characterization of the deposited coating was made using electron probe microanalysis, X-ray diffraction and microhardness tester. Dry sliding wear tests were carried out with a ball-on-disc type tribometer at room and elevated temperature. Worn surfaces of the samples were examined by the EDX equipped SEM and Raman spectroscopy.

Results revealed that at room temperature and 300°C plasticity dominated wear mechanism was operative. Under oxidation dominated wear conditions (400, 500, 600 and 700°C), testing temperature plays a crucial role on the characteristics of the oxide tribolayers formed on worn surfaces. Development of Cr2O3 in the tribolayer at 600 and 700°C was beneficial in increasing wear resistance of examined coating.

While the sliding wear performance of Stellite alloys at room temperature has been investigated in details, published studies on tribological behavior of Stellite alloys with varying temperature are scarce. Therefore, the present work was undertaken to study the wear mechanisms and the type of tribolayers formed during sliding wear of PTA welding deposited hypo-eutectic Stellite 12 coating with increasing temperature up to 700°C.

Friction stir welding (FSW) butt-joining involving the use of a dissimilar filler metal insert between the retreating and advancing portions of the workpiece is investigated computationally using a combined Eulerian-Lagrangian (CEL) finite element analysis (FEA). The emphasis of the computational analysis was placed on the understanding of the inter-material mixing and weld-flaw formation during a dissimilar-material FSW process. The paper aims to discuss these issues.

The FEA employed is of a two-way thermo-mechanical character (i.e. frictional-sliding/plastic-work dissipation was taken to act as a heat source in the energy conservation equation), while temperature is allowed to affect mechanical aspects of the model through temperature-dependent material properties. Within the analysis, the workpiece and the filler-metal insert are treated as different materials within the Eulerian subdomain, while the tool was treated as a conventional Lagrangian subdomain. The use of the CEL formulation within the workpiece insert helped avoid numerical difficulties associated with excessive Lagrangian element distortion.

The results obtained revealed that, in order to obtain flaw-free FSW joints with properly mixed filler and base materials, process parameters including the location of the tool relative to the centerline of the weld must be selected judiciously.

To the authors’ knowledge, the present work is the first reported attempt to simulate FSW of dissimilar materials.

Plasma transferred arc (PTA) coating is a novel method for surface-coating applications. In this method, the substrate is melted using a plasma arc, and surfacing agents such as carbides are introduced to the melt pool. The purpose of this study is to investigate the effect of boron carbide (B₄C) in nickel-based coating on AISI 4140 steel.

Samples were tested on a ball-on-disc wear device, and the microstructure, as well as wear properties, were investigated using SEM and XRD.

The effect of B₄C addition was shown to be linear, with a p-value of 0.0248, indicating strong evidence. The reason for this increase was found to be the increase in third-body generation resulting from hard phases that form couples with the soft base material, nickel. It was concluded that using 6 per cent B₄C was the optimal solution.

In the literature, the effect of neither low temperature on a nickel coating with B₄C nor B₄C as a single surfacing agent in a nickel base has been investigated.

This study proposes a DfMA (Design for Manufacture and Assembly) based on unmanned aerial vehicle (UAV) and uses Iranian-Islamic Muqarnas as the main case study due to their geometric modularity. In Islamic architecture, different geographic regions are known to have used various design and construction methods of “Muqarnas”, a type of decorated dome.

The paper presents a study on parametric analysis of the Iranian-Islamic Muqarnas and analyses its components, geometric relations and construction methods that should be considered when constructing one. This study aims to use the Muqarnas analysis as a driver to generate a DfMA basis on the UAVs and parametric fabrication. In Islamic architecture, different geographic regions use various design and construction methods of Muqarnas. There are four main parameters of the Muqarnas that define their classification; first, their three-dimensional shape, that provides volume. Second, the size of their modules is variable. Third, their own specific generative process-algorithm, and finally, the two-dimensional pattern plan that is used as a basis in the design. Thus, the authors present a global analytical study that drives a generative system to construct Muqarnas, through a careful balance of the four parameters.

This study thus presents a global analytical study that drives a generative system to construct Muqarnas, through a careful balance of four specifications. The paper reports the result of using a parametric tool, Grasshopper and parametric plugins, for creating a generative system of several types of Muqarnas. This synthetic translation aims at expanding our understanding of parametric analysis and synthesis of traditional architecture, advancing our understanding towards using parametric synthesis, with the scope to fabricate and assemble modules towards UAV-based fabrication of Muqarnas. To do so, the authors are taking advantage of their inherent repetition and recursion.

In the first step, this paper reviews studies on traditional Muqarnas (both Iranian and non-Iranian) and relevant parametric approaches. In the second step, the study aims to create a general generative system for Muqarnas. The creation of a generative system for Muqarnas is driven towards the creation of three-dimensional fabrication of their components so that these are assembled automatically using a swarm of UAVs. This particular drive imposes specific constraints in the parametric system, as the assembly of the final components, the authors posit, can only take place in a pick and place fashion.

The purpose of this study is to investigate the relationship between natural gas consumption and economic growth of France.

To analyze the relationship, an extended Cobb–Douglas production function is used. The auto-regressive distributive lag bounds testing approach is applied to test the existence of the long-run relationship between the series. The vector error correction model Granger causality approach is implemented to detect the direction of causal relation between the variables.

The results show that variables are cointegrated for the long-run relationship. They also indicate that natural gas consumption, exports, capital and labor are the contributing factors to economic growth in France. The causality analysis indicates that feedback hypothesis is validated between gas consumption and economic growth. The bidirectional causality is also found between exports and economic growth, gas consumption and exports and capital and gas consumption.

The feedback hypothesis between gas consumption and economic growth implies that adoption of energy conservation policies should be discouraged; rather, gas consumption and economic growth policies should be jointly implemented.

This study is an original work for France and shows the results of the relationship between natural gas consumption and economic growth. In line with the results of this study, new direction for policy makers is opened up to formulate a comprehensive energy policy to sustain long-term economic growth in France.

This study aims to investigate time-harmonic wave propagation in a chiral porous thermoelastic solid under strain gradient theory (SGT), focusing on identifying and characterizing distinct wave modes within the medium.

Using Iesan's gradient theory, which incorporates chiral effects and accommodates second sound phenomena, the authors derive mathematical formulations for the velocities and attenuations of eight propagating waves: four dilatational waves and two pairs of coupled shear waves (one left circularly polarized, the other right). Numerical simulations are performed for a specific model, exploring the influence of various parameters on wave propagation.

The authors establish that the medium supports four dilatational waves, including a microstretch-associated wave, and four shear waves, distinguished by their chiral-induced characteristics. The results highlight the frequency-dependent dispersive nature of all propagating waves and establish connections with existing theoretical frameworks, demonstrating the broader applicability of our findings.

The characteristics of wave propagation in chiral media examined here can enhance our understanding of chiral medium behavior. This knowledge is crucial for developing materials with pronounced chiral effects, surpassing those found in natural chiral materials like bone, quartz, sugar and wood. Advances in artificial chiral materials are driven by their superior toughness, durability and other beneficial properties. Consequently, this study has potential applications across various fields, including the design of chiral broadband absorbers and filters, the production of artificial bones and medical devices, aeronautical engineering and beyond.

This research extends existing theories and deepens the understanding by exploring wave behaviors in chiral media, advancing this emerging field.

The purpose of this paper is to study the influential factors in changing customers’ behaviors from online banking to mobile banking based on Tiller and Tad model.

A quantitative method was used. This study is a practical research work by using 400 people, among whom 384 participants were selected based on simple random sampling.

The results indicated that the perceived advantage of using mobile banking, the influence of peer groups, source facilitator conditions as well as technology had the highest correlation. Among the influential components on attitude, the highest level belongs to perceived advantage of using mobile bank. Among the effective factors on behavioral control, source facilitator conditions and technology facilitator conditions had the highest correlation.

It is suggested that the provided services be expanded via mobile banking and more customers be encouraged to use mobile banking services. For instance, the transaction of currency, stock, etc. via mobile banking is suggested. It is recommended that mobile banking software should be designed in a way that the process of mobile banking services is very easy for customers. Bank staff and employees should be trained to be active promoters of mobile banking services not only inside branch locations, but in other places and work environments as informers, messengers and models of using mobile banking.

It is recommended that bank managers should make use of the mass media such TV, billboard, radio, press, etc., in order to increase public awareness of mobile banking, and try to take effective steps in creating positive attitude in their customers on using mobile banking.

Mobile banking has evolved as a wireless communication interface for producing value by customers in banking transactions. Todays, one of the substantially remarkable modern techniques in providing banking services is the provision of financial and banking services by using smart phones (mobiles). Although the life of using smart phones for banking and financial operations is not too long, significant advancements have been observed in this area within a short time, which could highly promise the extensive development of this modern electronic banking technique in future.

During the last decade, information technology has had tremendous impacts on banking industry through guiding and introducing new financial products with a specific delivering to its customers, enabling the banks to be able to provide distinguished products and special services to their customers safely and reliably. It is more than 200 years since banks have served their customers through their branch systems. However, with the emergence of various types of technology, the nature of providing financial services has greatly changed, with the increasing growth in electronic commerce.