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The purpose of this study is to examine the effect of calcium-rich ingredients such as sesame, skimmed milk powder, moringa leaves, cumin seeds and finger millet on flour, dough and breads with the objective of developing bread with higher calcium content and to investigate whether it maintains quality traits that guarantee its acceptability by consumers by testing textural, scanning electron microscopy and nutritional and sensorial parameters.

Refined flour was fortified with skimmed milk powder (SMP), sesame, moringa leaves and cumin (T1), SMP, sesame and malted finger millet (T2) and SMP and sesame (T3). Refined flour dough and breads served as control (C). The physicochemical, textural, scanning electron microscopy, nutritional and sensory parameters of flour, dough and breads were evaluated.

Significantly (p < 0.01) higher stickiness values of dough were obtained by refined flour dough-C (50.3 N); refined flour dough fortified with SMP and sesame - T3 (42.2 N); Refined flour dough fortified with sesame, SMP and malted finger millet -T2 (38.4 N); and refined flour dough fortified with sesame, SMP, moringa leaves and cumin -T1 (33.5 N). Oven spring in breads was 1.4 in C and decreased significantly (p < 0.01) to T3-1.0, T1-0.9 and T2-0.8. Chewiness values of T3 (4.1) was similar to C bread, whereas T1 and T2 showed significantly (p < 0.01) lower values. Scanning electron microscopy images of bread microstructure showed fortification of bread resulted in intermittent but more prominent gluten structure in test breads than control. The highest calcium content was observed in T1 (268 mg/100 g), followed by T2 (231 mg/100 g) and T3 (211 mg/100 g). The incorporation of dried moringa leaves and cumin seeds enhanced the appearance, aroma, taste and flavor of T1.

The study shows that texturally and sensorially acceptable nutritious breads can be produced through natural fortification. Nutrients from naturally fortified foods are better absorbed and assimilated by the body. Calcium-fortified breads, each with its own distinctive taste and texture, showed high values in the sensory evaluation test.

The incorporation of calcium and protein-rich ingredients such as SMP, moringa leaves, cumin, malted finger millet and sesame would yield calcium enriched breads superior to the commonly consumed plain refined wheat flour bread with respect to textural, nutritional, functional and sensory attributes and have high potential to alleviate calcium deficiency in vulnerable groups.

This paper offers a brief review of the present use of scanning electron microscopy (SEM) in concrete studies, from the perspective of how research in materials science is translated into applications in construction engineering. It describes the scope of present use of the method, and attempts a prospective for the near future in areas where more work could make productive use of the technology. Selected case studies have also been discussed. The electron microscope has been used as a research tool in understanding the root cause of the differing performance of various types of concrete under various conditions, a development tool in making better concrete, and a diagnosis tool on problems like cracking of concrete. The paper also explains how sample preparation affects the type and quality of information which the SEM can produce.

The composition and thickness of surface oxide of solder particles is extremely important to the quality of interconnect and reliability of packaged system. The purpose of this paper is to develop an observable measurement to research the issue.

AES (Auger electron spectroscopy), XPS (X‐ray photoelectron spectroscopy), TEM (transmission electron microscopy) and STEM (scanning transmission electron microscopy) were employed to examine the oxide layer on microscale solder powders. Conventional techniques and FIB (Focus Ion Beam) were employed for the TEM sample preparation. High angle annular dark field (HAADF) pattern was applied to distinguish the oxide layer and the solder matrix by the contrast of average atomic number. The results were confirmed by AES and XPS measurement.

The solder powders were exposed to air (70% relative humidity) at 150°C for 0, 120 and 240 h for the accelerated growth of oxide. The surface oxide thickness was 6 nm and 50 nm measured by TEM for 0 h and 120 h samples, respectively. It was found that the increase in surface oxide thickness of solder particles is proportional to the rooting of time. The elemental distribution along the oxide was quantified by line scanning using STEM and the atomic ratio of Sn to O in the oxide layer nearer to the outer, the middle, and the inner (adjacent to the solder matrix) was found to be 1:2, 2:3 and 1:1, respectively. The result was validated using XPS which gave Sn to O ratio of 1:2 at 5 nm depth of surface oxide.

This is the first time FIB technology has been used to prepare TEM specimens for solder particles and TEM pictures shown of their surface oxide layer. Though requiring more care in sample preparation, the measurements by TEM and STEM are believed to be more direct and precise.

Three-dimensional (3D) printing is increasingly used to produce orthopaedic components for hip arthroplasty, such as acetabular cups, which show complex lattice porous structures and shapes. However, limitations on the quality of the final implants are present; thus, investigations are needed to ensure adequate quality and patients safety. X-ray microcomputed tomography (micro-CT) has been recognised to be the most suitable method to evaluate the complexity of 3D-printed parts. The purpose of this study was to assess the reliability of a micro-CT analysis method comparing it with reference systems, such as coordinate measuring machine and electron microscopy.

3D-printed acetabular components for hip arthroplasty (n = 2) were investigated. Dimensions related to the dense and porous regions of the samples were measured. The micro-CT scanning parameters (voltage – kV, current – µA) were optimised selecting six combinations of beam voltage and current.

Micro-CT showed good correlation and agreement with both coordinate measuring machine and scanning electron microscopy when optimal scanning parameters were selected (130 kV – 100 µA to 180 kV – 80 µA). Mean discrepancies of 50 µm (± 300) and 20 µm (± 60) were found between the techniques for dense and porous dimensions. Investigation method such as micro-CT imaging may help to better understand the impact of 3D printing manufacturing technology on the properties of orthopaedic implants.

The optimisation of the scanning parameters and the validation of this method with reference techniques may guide further analysis of similar orthopaedic components.

Electron beam is a way of radiation that can induce different reactions on polymers. The purpose of this work is to analyze the effect that the electron beam can produce on polyester fabrics.

Poly(ethylene terephthalate) (PET) fibres were treated at 0, 50, 100, 150, and 200 KGy. Later on surface modification was analyzed by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). Colorimetric and thermal measurements were studied too, as well as traction resistance.

Traction resistance showed no significant variations. As a result the authors could observe some changes in fabric witnesses and cristallinity increase, but no changes in traction resistance were observed. Moreover, when surface was studied, roughness was increased as oligomers moved towards fibre surface because of radiation dose.

The authors could appreciate roughness increased with radiation dose as well as yellowness and crystallinity.

The purpose of this paper is to compare a picture obtained by means of electron microscopy, resulting from the interaction of an electron beam with the material surface, and the numerical mapping of the material surface potentials. This new method has been successfully applied to a composite material and will be checked to describe other complex materials.

This surface potential function is calculated by a numerical approximation of Laplace's equation with three variables reduced to two variables by using the continuity assumptions on the potential.

The results are particularly satisfactory and allow future developments in electron microscopy picture analysis to be forecasted.

This paper demonstrates new approximated operator of the surface potential with good accordance between experimental and calculated values.

The purpose of this study is to understand the inhibitor behavior of specific drug against mild steel corrosion and their adsorption mechanism on the surface.

Corrosion rates are influenced by the formation of inhibitor aggregates at the mild steel surface. Detail surface characterizations of mild steel have been studied before and after adsorption of drugs in 1N HCl solution. Scanning electron microscopy, atomic force microscopy and Fourier transform infrared spectroscopy were used to examine the effect of drug adsorption on steel surface.

Scanning electron microscopy analysis suggested that the metal had been protected from aggressive corrosion because of the addition of the inhibitors. Atomic force microscopy visualization confirmed the formation of protective layer on steel surface, resulting in the decrease in surface roughness with corrosion rates. The nature of metal surface has been analyzed by Fourier transform infrared spectroscopy.

The findings of this study will help us to understand the interaction of specific drugs with mild steel surface and their potential inhibition mechanism.

The objective of this paper is to determine fretting parameters of hoisting rope according to the hoisting parameters in coalmine and to explore the effect of contact load on fretting-fatigue behavior of steel wires.

Based on the mechanical model of hoisting rope in coalmine, the dynamic tension simulation of hoisting rope was performed. Static equations of hoisting rope under tension and torsion and theories of contact mechanics were applied to obtain fretting parameters. Fretting-fatigue tests of steel wires at different contact loads were conducted using a fretting-fatigue test rig. The fretting regime, normalized tangential force and fretting-fatigue life were studied. The morphologies of fretting contact scars and fracture surfaces were observed by scanning electron microscopy and optical microscopy to examine wear and failure mechanisms.

Dynamic tension changes from 0 to 30,900 N. In outer strand layer, contact loads between steel wires in certain wire layers are 60.5 and 38.3 N compared with 378 and 102.7 N between wire layers; relative displacements between wires are 62.5 and 113.2 μm, respectively. Mixed fretting regimes develop in all cases. Increasing contact load decreases the stabilized relative slip and normalized tangential force, reduces the fretting fatigue life, induces accelerated adhesive wear and fatigue wear and results in rougher fracture surface topographies. In all cases, fretting zone induces crack initiation; crack propagation and rupture zones present brittle cleavage and longitudinal splitting, respectively.

This paper presents the systemic study on determination of fretting parameters of hoisting rope according to the hoisting parameters in coalmine and the fretting-fatigue behavior of its internal steel wires. The results of fretting-fatigue tests show that the increase of contact load decreases the stabilized relative slip in mixed fretting regime and normalized tangential force, reduces the fretting fatigue life, induces accelerated adhesive wear and fatigue wear and results in rougher fracture surface topographies.

The authors warrant that the paper is original submission and is not being submitted to any other journal. And the research does not involve confidentiality, copyright infringement, leaks and other issues, all the responsibilities that the authors will take.

A mechanical and microstructural study was performed of 43/43/14 tin/lead/bismuth solder. This alloy melts lower than the commonly used tin/lead solders and therefore holds promise as a useful material in two‐step soldering processes or in processes with thermally sensitive components. Mechanical testing of 43/43/14 tin/lead/bismuth showed a strength comparable to that of tin/lead solders but increased creep rate. Microstructural analysis (scanning electron microscopy/energy dispersive X‐ray) exhibited the same mechanism of fatigue as for tin/lead solders, viz., heterogeneous coarsening. Thermocyclic fatigue demonstrated that the long‐term reliability of 43/43/14 tin/lead/bismuth is comparable to that of tin/lead solders.

The range of applications of the currently available biomass selective laser sintering (SLS) parts is limited and low-quality. This study aims to demonstrate the effects of the various processing parameters on the dimensional accuracy, bending strength, tensile strength, density and impact strength of the Prosopis chilensis/polyethersulfone (PES) composites (PCPCs) that were produced by SLS. The various processing parameters are laser power, scan speed, preheating temperature, scan spacing and layer thickness. In addition, the authors’ studied the effects of PCP particle size on the mechanical properties of the PCPCs.

The PCPC specimens were printed using an AFS SLS machine (additive manufacturing). The bending, tensile and impact strengths of the specimens were measured using a universal tensile tester. The dimensional accuracy of the bending specimens was determined by a Vernier caliper. The formability of the PCPC at various mixing ratios of the raw materials was earlier investigated by single-layer sintering experiments (Idriss et al., 2020b). The microstructure and particle distribution of the various PCPC specimens were analyzed by scanning electron microscopy (SEM).

The mechanical strengths (bending, tensile and impact strengths and density) and the dimensional accuracy of the PCPC SLS parts were directly and inversely proportional, respectively, to the laser power and preheating temperature. Furthermore, the mechanical strengths and dimensional accuracy of the PCPC SLS parts were inversely and directly proportional, respectively, to the scanning speed, scan spacing and layer thickness.

PCPC is an inexpensive, energy-efficient material that can address the drawbacks of the existing SLS parts. It is also eco-friendly because it lowers the pollution and CO₂ emissions that are associated with waste disposal and SLS, respectively. The optimization of the processing parameters of SLS in this study produced high-quality PCPC parts with high mechanical strengths and dimensional accuracy that could be used for the manufacture of the roof and wooden floors, construction components and furniture manufacturing.

To the best of the authors’ knowledge, this study is among the first to elucidate the impact of the various SLS processing parameters on the mechanical properties and dimensional accuracy of the sintered parts. Furthermore, novel PCPC parts were produced in this study by SLS.