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Corrosion poses a significant threat to the longevity and integrity of metallic structures, leading to substantial economic losses globally. Traditional corrosion protection methods often have drawbacks, such as increased thickness, altered physical properties, and environmental concerns. In recent years, superhydrophobic coatings have emerged as promising solutions for corrosion protection due to their exceptional water-repellent properties. This research investigates hydrophobicity and corrosion resistance enhancement in eco-friendly copper-coated aluminium through further modification with polypropylene/myristic acid (PP/MA). Electrodeposition of copper on aluminium substrate resulted in a distinctive rose flower-like micro-order rough structure, elevating the contact angle from 58° to 140° (highly hydrophobic) when voltage varying up to 10 V, with the highest hydrophobicity observed at 8 V. Subsequent modification with PP/MA (4:1) further increased the contact angle to 148° (superhydrophobic) and reduced the surface energy, enhancing hydrophobicity. Measurements of corrosion resistance exhibited substantial enhancements, with anti-corrosion efficiency achieving 99%, polarisation resistance at 91200 Ω cm2, and a minimal corrosion rate of 0.000132 mm/year. The enhanced corrosion resistance is due to the rough structure, which reduces electrolyte contact and minimises the surface area exposed to the electrolyte. The stability studies demonstrated that the altered superhydrophobic coating retained a contact angle exceeding 120° even when subjected to severe conditions such as elevated temperatures (up to 180 °C), high pressure, and a 52-day submersion in a 3.5% NaCl solution. The stability of polypropylene is due to the presence of strong metallic and coordination bonds, as well as the inertness and strength of the material itself. These results indicate that the modified coating producing long-lasting hydrophobic and corrosion-resistant characteristics, making it suitable for various industrial applications.

The Hartha Formation (Late Campanian-Maastrichtian) has been recognized as a potential reservoir for hydrocarbons in various oilfields within the Mesopotamian basin in central Iraq. The formation has conformable upper contact with the overlying Shiranish Formation but unconformable lower contact with the underlying Mushorah Formation. This formation has been stratigraphically divided into two main parts. The lower part is particularly significant as it is recognized as an important stratigraphic unit due to the presence of oil shows. Five subsurface sections and many thin sections of the Hartha Formation (Late Campanian-Maastrichtian) were studied to unravel the depositional facies and environments. The sedimentary microfacies of the Hartha Formation in the Balad oil field include mudstone, wackestone, wackestone to packstone, packstone, Packstone to Grainstone, and Rudstone. These depositional microfacies have been subdivided according to their primary and diagenetic constituents into six sub-microfacies. The microfacies have been deposited in deep shelf margin, open shelf, and foreslope of varying salinities and energy levels. Cementation, dolomitization, compaction and pressure solution (stylolitization ), and dissolution are observed affecting variably both ground mass and particles. These diagenetic processes have both positive and negative effects on porosity types, causing fluctuations in porosity levels. The primary pore types identified within the study wells include interparticle porosity, intercrystal porosity, moldic porosity, vuggy porosity, channel porosity, and fracture porosity.

An exceptional method of incorporating Sn ions into Zinc Oxide (ZnO) using a tandem system of Pulsed Laser Deposition (PLD) and Radio-Frequency Magnetron Sputtering (RFMS) to synthesize and functionalize ZnO nanostructures is demonstrated in this study for gas-sensing application. The RFMS power was varied up to 50 W to sputter a pure Sn metal target, while simultaneously or successively growing ZnO nanostructures on a templated MgO substrate and on an Au-plated Al2O3 gas sensor, via PLD process at the substrate temperature of 700 °C in 100–500 millitorr oxygen/argon gas background. The morphologies of the grown Sn-ZnO nanostructures were characterized by Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), and X-ray Diffraction (XRD), and while their chemical/oxidation states and optical properties were analyzed by X-ray photospectroscopy (XPS) and photoluminescence (PL), respectively. For simultaneous deposition, the resulting (0002)-dominated 2D grain-like ZnO nanostructures were influenced by the interaction of the dynamic PLD plasma with static RFMS plasma at different powers. For successive growth, at 50 W-RF power, a remarkable increase in the sensor response to 50-ppm carbon monoxide (CO) gas was observed at 250 °C, which could be attributed to the creation of more adsorption sites in the Sn-ZnO depletion region caused by the replacement of some Zn sites with Sn ions in the ZnO matrix. This study, therefore, exhibits the viability of this hybrid system to design, synthesize, and functionalize Sn-ZnO nanomaterials, either by simultaneous/successive deposition, for gas-sensing applications.

This study investigates solid-state diffusion bonding between two INCONEL 617 alloy samples using field-assisted sintering technology (FAST). The study focuses on analyzing the faying surface validating the theoretical alloy design modeling done by the CALculation of PHAse Diagrams (CALPHAD) approach followed by experimental validation. Varying kinetics’ limitations enabled phase stability and phase control governed by the CALPHAD approach alloy design. The alloy design contains a pseudo-binary phase diagram assisted with thermal mapping of a property phase diagram to obtain the optimum temperature of solid-state diffusion bonding while understanding phase fields and their evolution through Molybdenum (Mo) increasing content and temperature increase. The FAST parameters recommended by CALPHAD were 800 °C under 10 MPa pressure with a holding time of 30 min. The investigation observations were promising in a way that the faying surface contains gamma ( γ ) only, while the further region on the alloy contains γ and gamma prime ( γ ′). It is worth mentioning that FAST joining resulted in fine faying surface thickness of around 10 μ m and a controlled heat affected zone (HAZ) leading to relevant reduction in the recrystallization zone yielding an average grain size of 60–100 μ m before and after diffusion bonding. Furthermore, two modes of metal carbide (MC) have been found; MC formed under the faying surface and micro-MC pools formed around the faying surface.

The microstructural and mechanical properties investigation on powder metallurgy (PM) Ti-Zr composite alloys dispersed with TiC particles via sintering and hot rolling process was carried out in this study. PM Ti-Zr-TiC composites were fabricated from the pre-mixed pure Ti, metal Zr and TiC powders, and heat treatment was applied to the sintered materials to homogenize Zr solid-solution in α-Ti matrix. XRD analysis results of these rolled composite materials indicated complete solid-solution of Zr elements. Microstructures observation clarified the binary Ti-(10-20%)Zr alloys had a mean grain size of around 4 μm, which was much smaller compered to pure Ti material with 10 μm grain diameter. According to the tensile test results, Ti-Zr alloys showed a remarkable increment of tensile strength due to Zr solid-solution and α-Ti grain refinement, and also had a large elongation. On the other hand, since Young’s modulus gradually decreased with increased in Zr content, TiC particles were added into Ti-10%Zr alloy to improve the modulus. The uniform dispersion of (2.5-5 wt%)TiC particles in the matrix resulted in the increase of both Young’s modulus and tensile strength. The experimental values of Young’s modulus showed a good agreement with the calculated ones by using the law of mixture. [ABSTRACT FROM AUTHOR]

In this paper, a unique hybrid approach to design and synthesize 2D/3D Al2O3-ZnO nanostructures by simultaneous deposition is presented. Pulsed laser deposition (PLD) and RF magnetron sputtering (RFMS) methods are redeveloped into a single tandem system to create a mixed-species plasma to grow ZnO nanostructures for gas sensing applications. In this set-up, the parameters of PLD have been optimized and explored with RFMS parameters to design 2D/3D Al2O3-ZnO nanostructures, including nanoneedles/nanospikes, nanowalls, and nanorods, among others. The RF power of magnetron system with Al2O3 target is explored from 10 to 50 W, while the ZnO-loaded PLD’s laser fluence and background gases are optimized to simultaneously grow ZnO and Al2O3-ZnO nanostructures. The nanostructures are either grown via 2-step template approach, or by direct growth on Si (111) and MgO substrates. In this approach, a thin ZnO template/film was initially grown on the substrate by PLD at ~300 °C under ~10 milliTorr (1.3 Pa) O2 background pressure, followed by growth of either ZnO or Al2O3-ZnO, using PLD and RFMS simultaneously under 0.1–0.5 Torr (13–67 Pa), and Ar or Ar/O2 background in the substrate temperate range of 550–700 °C. Growth mechanisms are then proposed to explain the formation of Al2O3-ZnO nanostructures. The optimized parameters from PLD-RFMS are then used to grow nanostructures on Au-patterned Al2O3-based gas sensor to test its response to CO gas from 200 to 400 °C, and a good response is observed at ~350 °C. The grown ZnO and Al2O3-ZnO nanostructures are quite exceptional and remarkable and have potential applications in optoelectronics, such in bio/gas sensors.

This research is aimed at the up-gradation of indigenous Pakistani iron ore, i.e., Dilband iron ore (hematite), by utilizing common metallurgical processes. First, the magnetic properties of the ore were determined. Initially, the iron ore samples contained 34 wt. % Fe in addition to other gangue materials. Therefore, the ore was subjected to a high-temperature reduction roasting process between 800 °C and 1000 °C. Additionally, the magnetic separation process was also employed. The influence of different roasting parameters, such as the reduction time, coal-to-ore ratio, and temperature, was examined. This was followed by characterization techniques using XRD (X-ray diffraction analysis), the Rietveld method, wet chemistry analysis, and a VSM (Vibrating Sample Magnetometer). The results suggest an excellent reduction at 900 °C for a coal/ore ratio of 20 wt. %, which was achieved within 2 h of the process. The Fe concentration increased tremendously from 34 to 56 wt. %, and in conjunction, magnetic properties were also induced (1.5 emu). The recovery was found to be substantial for the ore when the Fe content was 75 wt. %. Additionally, the economic feasibility of the processed ore was also studied, followed by an extensive analysis of the roasting and magnetic separation processes.

This work focuses on preparing TiO2, CdS, and composite TiO2:CdS thin films for photovoltaic applications by thermal evaporation. The suggested materials exhibit very good optical and electrical properties and can play a significant role in enhancing the efficiency of the device. Various microscopy and spectroscopy techniques were considered to investigate the optical, morphological, photoluminescence, and electrical properties. FTIR confirms the material identification by displaying some peaks in the fingerprint region. UV Vis spectroscopy yields high transmission (80–90%) and low absorbance (5–10%) within the spectral region from 500 nm to 800 nm for the composite thin films. The optical band gap values for CdS, TiO2, and TiO2:CdS thin films are 2.42 eV, 3.72 eV, and 3.6 eV. XRD was utilized to analyze the amorphous nature of the thin films, while optical and SEM microscopy were employed to examine the morphological changes caused by the addition of CdS to TiO2. The decrease in the bandgap of the composite thin films was determined by the Tauc plot, which is endorsed due to the band tailing effects. Photoluminescence spectroscopy depicts several emission peaks in the visible region when they are excited at different wavelengths, and the electrical measurement enhances the material conductivity. Furthermore, the proposed electron transport materials (TiO2, CdS, TiO2:CdS) were simulated with different perovskite materials to validate their design by employing the SCAPS-1D program and assess their performance in commercial implementation. The observed results suggest that TiO2:CdS is a promising candidate to be used as an ETM in PSC with enhanced productivity.

Nickel-supported hierarchical zeolite catalysts were prepared through a desilication reassembly process under optimized conditions and applied in one-pot menthol synthesis. In this work, the hierarchical zeolite-supported metal bifunctional catalysts were prepared with the help of desilication re-assembly and wetness impregnation techniques and applied in menthol synthesis via citral hydrogenation. The prepared catalysts were characterized using PXRD, BET, FE-TEM, NH3-TPD, H2-TPR, pyridine adsorption, and ICP-OES techniques. As a result, the physicochemical and acidic properties, such as mesopore surface area, metal dispersion, acidity, catalytic activity, and strong Lewis acid sites of pure microporous ZSM-5/USY zeolites, were significantly improved. Consequently, with the occurrence of superior physicochemical and acidic properties, the Ni/HZ-0.5 M catalyst exhibited outstanding catalytic activity (100% conversion, TOF 7.12 h−1) and menthol selectivity (83%, 4 h) with uniform stability at 100 °C, 1.0 MPa hydrogen. Similarly, the cracking rate decreased with the decrease in Bronsted acid sites.

Globally, the petroleum industry plays a very significant role in producing oil to fulfil the demand of the growing population. The improper management of abandoned quantity of petroleum sludge that is one of the byproducts of petroleum industry has posed many environmental as well as socio-economic issues in most of the developing countries. The petroleum sludge contains various toxic substances, like minerals, oil, and other chemicals which are very harmful for biotic as well as abiotic environment. Meanwhile, a huge quantity of livestock manure, especially buffalo dung, is produced in villages and burned as fuel after drying in open atmosphere for domestic application without any treatment which generates indoor air pollution. This study was formulated to analyze the biochemical methane potential of buffalo dung with petroleum sludge at different mixing ratios (i.e., 1:1, 1.5:0.5 and 0.5:1.5) through batch digestion system. The substrates were prepared and characterized before and after batch digestion by using standard methodology. The maximum methane was obtained as 268 Nml/gVS, followed by 326 Nml/gVS and 191 Nml/gVS at mixing ratios of 1:1, 1.5:0.5 and 0.5:1.5, respectively. The results and findings of the study indicated that the co-digestion of buffalo dung with petroleum sludge at mixing ratio of 1.5:0.5 through continuous batch digestion would be the best option to enhance methane production. [ABSTRACT FROM AUTHOR]

Abstract The enhanced sensitivity of up-conversion luminescence is imperative for the application of up-conversion nanoparticles (UCNPs). In this study, microfibers were fabricated after co-doping UCNPs with polymethylmethacrylate (PMMA) and silver (Ag) solutions. Transmission losses and sensitivities of UCNPs (tetrogonal-LiYF4:Yb3+/Er3+) in the presence and absence of Ag were investigated. Sensitivity of up-conversion luminescence with Ag (LiYF4:Yb3+/Er3+/Ag) is 0.0095 K−1 and reduced to (LiYF4:Yb3+/Er3+) 0.0065 K−1 without Ag at 303 K under laser source (980 nm). The UCNP microfibers with Ag showed lower transmission losses and higher sensitivity than without Ag and could serve as promising candidate for optical applications. This is the first observation of Ag-doped microfiber via facile method.

Aluminum nitride (AlN) is a semiconductor material possessing a hexagonal wurtzite crystal structure with a large band gap of 6.2 eV. AlN thin films have several potential applications and areas for study, particularly in optoelectronics. This research study focused on the preparation of Ni-doped AlN thin films by using DC and RF magnetron sputtering for optoelectronic applications. Additionally, a comparative analysis was also carried out on the as-deposited and annealed thin films. Several spectroscopy and microscopy techniques were considered for the characterization of structural (X-ray diffraction), morphological (SEM), chemical bonding (FTIR), and emission (PL spectroscopy) properties. The XRD results show that the thin films have an oriented c-axis hexagonal structure. SEM analysis validated the granular-like morphology of the deposited sample, and FTIR results confirm the presence of chemical bonding in deposited thin films. The photoluminescence (PL) emission spectra exhibit different peaks in the visible region when excited at different wavelengths. A sharp and intense photoluminescence peak was observed at 426 nm in the violet-blue region, which can be attributed to inter-band transitions due to the incorporation of Ni in AlN. Most of the peaks in the PL spectra occurred due to direct-band recombination and indirect impurity-band recombination. After annealing, the intensity of all observed peaks increases drastically due to the development of new phases, resulting in a decrease in defects and a corresponding increase in the crystallinity of the thin film. The observed structural, morphological, and photoluminescence results suggest that Ni: AlN is a promising candidate to be used in optoelectronics applications, specifically in photovoltaic devices and lasers.

There are two common categories of implants that are used in medical sciences, i.e., orthopedic and dental ones. In this study, dental implant materials are focused such as Ti6Al4V alloys that are used for the replacement of lost teeth due to their high strength and biocompatibility. However, they cause infections in nearby tissues due to elemental release (potentially Al and V). Thus, manganese is selected to be incorporated into the alloy since it is also present in the human body in the form of traces. Different sets of implants were produced, i.e., Ti5Mn and Ti10Mn (where 5 and 10 describe the percentage of Mn) by using the powder metallurgy technique. This was followed by characterization techniques, including X-ray fluorescence spectroscopy (XRF), X-ray diffractometer (XRD), optical microscope (OM), and nanoindenter. The very aim of this study is to compare the microstructural evolutions, density, and mechanical properties of reference alloys and the ones produced in this study. Results show the microstructure of Ti6Al4V consists of the alpha (α) and beta (β) phases, while Ti5Mn and Ti10Mn revealed the beta (β) phases. The Ti5Mn alloy showed excellent mechanical properties than that of the Ti6Al4V counterpart. Extensive discussion is presented in light of the observed results. The relative density of Ti5Mn alloy was found to be enhanced than that of reference alloy.

Sheets of aluminum 7075 and titanium Ti-6Al-4V alloys were successfully joined using the spark plasma sintering (SPS) process. A copper foil was placed as an interlayer between the two surfaces. The bonding was made at 480 °C, 500 °C, and 520 °C with a holding time of 10 min and under a uniaxial pressure of 5 MPa and 10 MPa. The obtained bonds were analyzed by scanning electron microscopy, energy dispersive spectroscopy (SEM/EDS), and wavelength dispersive spectroscopy (WDS). It was found that copper diffused away through Al7075 and formed Al2Cu intermetallics but was not present at the joint region. The investigation of the fractured surfaces using X-ray diffraction (XRD) showed that the joint region contained TiAl3, TiAl2, and Ti3Al intermetallic compounds. The presence of the Cu foil was believed to hinder the formation of Al3Ti observed in previous studies by allowing more Ti to diffuse into the Al side.

Introduction: Impairment in kidney function leads to disturbed thyroid physiology. All levels of the hypothalamic-pituitary-thyroid axis may be involved, including alterations in hormone production, distribution, and excretion, and even CKD progress with hypothyroidism. Aim of Work: To assess the prevalence of hypothyroidism among chronic kidney disease patients. Materials and Methods: A cross-sectional analysis was conducted in the nephrology department of security forces hospital from January 2015 to February 2018. Biochemical tests (includes blood urea, serum creatinine, PTH, total T4, TSH) were carried out to all participants. Results: Out of 255 CKD patients in the present study, 166 patients had no hypothyroidism, 43 had subclinical hypothyroidism, and 46 had hypothyroidism. The percentage of hypothyroidism among CKD patients was 34.9%, including dialysis patients and 17.66% after exclusion. Out of 24 peritoneal dialysis patients in the current study (P = 0.03), 7 had subclinical hypothyroidism and another 7 had hypothyroidism. In addition, out of 139 hemodialysis patients (P = 0.02), 20 patients had subclinical hypothyroidism and 18 had hypothyroidism. The majority (67.36%) of CKD patients were in CKD stage 5 and had no hypothyroidism (45.10%). Only 29 (11.37%) patients in CKD stage 5 had hypothyroidism and 28 (10.89%) patients had subclinical hypothyroidism. T4 was higher in nondialysis patients, whereas TSH and PTH were higher in dialysis patients. Conclusion: The prevalence of hypothyroidism among chronic kidney disease patients was high and increased with the decrease in estimated GFR.