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The lightweight die-casting Al-alloys have become a more appropriate material in many industrial applications. However, the product’s quality has been affected due to existing internal casting defects and the impregnation technique used to overcome drawbacks and improve alloys’ useability. This paper discusses the use of microfocus X-ray computed tomography (XCT) to examine Al-alloy’s die-casting internal deformity, identify the impregnation technique’s effectiveness in sealing porosity non-destructively. Also, we recognize the presence of low atomic number polymer resin (P601) inside the alloy’s defects quantitatively. 3D CT images with transparent effects were generated with a direct conversion X-ray flat panel detector to visualize internal casting defects in the entire samples. The gray-value contrast of 2D slice CT images was excellent to distinguish the resin material in the alloy samples qualitatively. The dimensional analysis shows that the impregnated resin does not seal the casting cavity homogeneously, and some air bubbles appeared inside the defects. The dual-energy X-ray CT technique with a photon-counting detector was executed to characterize the impregnant resin in die-casting cavities by its effective atomic numbers. The outcome shows that the resin material present in alloy’s defects is identical to the solid P601 super-sealant impregnant resin, with a 1.81% error margin. Hence, the XCT technique with a direct-conversion CdTe detector can be used as a rapid and detailed non-destructive inspection technique in die-casting industries and improve the impregnation process’s performance.

This paper describes the use of X-ray computed tomography (XCT) to inspect the internal defects of industrial Aluminum alloys die-casting, to justify the adequateness of super sealant resins in filling tiny holes, and to reduce the casting porosity of metals by the impregnation process. High-resolution 2D slice images were generated by a microfocus X-ray CT system with direct conversion Cadmium Telluride (CdTe) flat panel detector (FPD). Moreover, we were able to visualize the internal defects of the two different shapes of casting objects. The gray-value contrasts of the CT images were excellent to distinguish the resin material in the alloy samples after impregnation treatment. Furthermore, to determine the dimensions of internal defects, virtual sectioning was carried out to view the cross-section of the metal samples and dimensions of internal defects. Dual-energy X-ray computed tomography (DXCT) was used with an energy differentiation type 64-pixel linear array photon-counting line sensor for the material characterization. The impregnated resin part inside the castings defects was verified based on the effective atomic number with a 2.92% low error margin. Hence, this will be a useful qualitative and quantitative advancement to rapid and detailed non-destructive analysis within the die-casting industries in improving the quality of the impregnation process.

A novel Spray Pyrolysis (SP) technique, known as Pulsed Atomized Spray Pyrolysis (PASP), was developed and deployed to prepare thin films of various nanotechnological architectures of fluorine-doped tin (IV) oxide (FTO) layers on glass surfaces. This technique allows for the perfect control of morphology of nanotechnological architectures of FTO, which can be achieved simply by controlling spray duration. As such, 0-D nanocrystallites, 1-D uncapped nanorods and 1-D capped nanorods; all in 2-D thin layers, and extensively cross-linked 3-D nanotechnological architectures of FTO can be prepared, on soda lime glass surfaces. This is the first time report on kinetically-controlled growth of different nanotechnological architectures of FTO, using the same technique. X-Ray Diffraction (XRD), Scanning Electron Microscopic (SEM) and X-Ray Photoelectron Spectroscopic (XPS) data show excellent correlations. As evident from XPS data, FTO uncapped nanorods were found to contain more Sn 2 + sites on their surfaces when compared to those of other nanotechnological architectures. ATR-FT-IR spectrum shows F Sn F and F Sn stretching vibrations in all forms of FTO nanostructures. Thin layers have optical transmissions in the range 70% to 85%, in the visible range of the electromagnetic spectrum. This technique is versatile and is not limited only to fabricate FTO nanostructures, but, it can also be used to fabricate thin layers of nanotechnological structures of different dimensionalities of various materials on various substrates, which is capable to withstand required pyrolytic temperatures.

In this study the novel spray pyrolysis technique, known as rotational, pulsed and atomized spray deposition method was used to fabricate vertically aligned and well separated FTO One-dimensional nanostructures on glass substrate. It was confirmed that spraying at low angle to the substrate is mandatory for the crystal growth of vertically aligned nanorods. The preferential orientation of nanorods crystallites along the (101) direction and prepared nanorods thin film showed an excellent transparency of 84.8% and a low resistance of 26.7 Ω/sq.

This paper describes the preparation and characterization of optically-transparent thin films of fluoride-doped tin oxide (FTO) nanoparticles, nanotubes and nanorods grown using purpose-built, novel and advanced version of spray pyrolysis technique, known as Rotational, Pulsed and Atomized Spray Pyrolysis. Uniform and crack-free FTO1-D nanostructured thin films over 50 mm × 50 mm soda lime glass substrate have been routinely achieved. This technique allows a perfect control of morphology of nanostructures of FTO layer simply by adjusting the spray conditions. Formed 1-D FTO nanostructures on the glass substrate show an excellent optical transparency in the visible light range. XRD (x-ray diffraction) and SEM (scanning electron microscope) data show excellent correlations.

Trehalose is known to protect cells from various environmental assaults; however, its role in the ethanol tolerance of Saccharomyces cerevisiae remains controversial. Many previous studies report correlations between trehalose levels and ethanol tolerance across a variety of strains, yet variations in genetic background make it difficult to separate the impact of trehalose from other stress response factors. In the current study, investigations were conducted on the ethanol tolerance of S. cerevisiae BY4742 and BY4742 deletion strains, tsl1Delta and nth1Delta, across a range of ethanol concentrations. It was found that trehalose does play a role in ethanol tolerance at lethal ethanol concentrations, but not at sublethal ethanol concentrations; differences of 20-40% in the intracellular trehalose concentration did not provide any growth advantage for cells incubated in the presence of sublethal ethanol concentrations. It was speculated that the ethanol concentration-dependent nature of the trehalose effect supports a mechanism for trehalose in protecting cellular proteins from the damaging effects of ethanol.