(Fe1-xGax)92Zr8 amorphous and nanocrystalline alloys with x = 0.15 to x = 0.36 were investigated to improve the magnetic softness of Galfenol-type alloys and to evaluate their magnetostrictive properties. The samples were prepared by melt spinning of arc melted ingots. The rapidly solidified ribbons were annealed at 823 K for 1 h to produce a nanocrystalline structure. X-ray Diffraction data showed that after annealing, bodycentered cubic (BCC) Fe-Ga phase crystallized for x = 0.15 to x = 0.26. When x exceeded 0.26, the ribbons crystallized into BCC and a ternary intermetallic phase (i.e., ZrFe6Ga6) which has deteriorating effect on saturation magnetization, magnetic softness and magnetostriction coefficient. The annealed ribbons' saturation magnetization value decreases from 126 Am2/kg to 54 Am2/kg as the Ga content increased from x = 0.15 to x = 0.36. The alloy with x = 0.26 annealed at 823 K for 1 h shows a peak magnetostriction of 10 ppm with saturation magnetization of 110 Am2/kg and coercivity of 260 A/m. (c) 2023 Elsevier B.V. All rights reserved.

Activated carbon/titanium dioxide (AC/TiO2) nanohybrids were synthesized by a hydrothermal technique using various weight percent of commercial AC and were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Fourier transform infrared (FTIR) and thermogravimetric analysis (TGA). The synthesized nanohybrids were applied to photodegradation of Reactive Red-35 (RR-35) dye in aqueous solution using sunlight. Due to the synergistic effect of adsorption and photodegradation activity, AC/TiO2 nanohybrids were more efficient in treating the aqueous dye solution than that of AC and TiO2. The maximum (95%) RR-35 dye removal from the water was obtained with 20 wt% AC/TiO2 within 30 min at natural pH of 5.6. The possible photodegradation mechanism of RR-35 dye with AC/TiO2 was discussed from the scavenger test. Moreover, AC/TiO2 was found to be suitable for long-term repeated applications through recyclability experiments. Therefore, AC/TiO2 nanohybrid is a promising photocatalyst for treating azo dyes especially RR-35 from water.

1 School of Chemical and Materials Engineering, National University of Sciences and Technology, Islamabad 44000, Pakistan; adeelriaz03@gmail.com (A.R.); amnaashraf04@hotmail.com (A.A.); hymnataimoor94@live.com (H.T.); sofia.javed@scme.nust.edu.pk (S.J.); aftabakram@scme.nust.edu.pk (M.A.A.); drmmujahid@gmail.com (M.M.) 2 Center of Excellence for Research in Engineering Materials (CEREM), Deanship of Scientific Research, King Saud University, P. O. Box 800, Riyadh 11421, Saudi Arabia; ifahmad@ksu.edu.sa 3 Department of Mechanical Engineering, College of Engineering, King Saud University, P. O. Box 800, Riyadh 11421, Saudi Arabia; khaliduetp@gmail.com * Correspondence: miqureshi@ksu.edu.sa; Tel.: +966-544523909

This study presented a technique to deposit high strength and highly conductive copper thin films on glass substrates at room temperature. In this work, Cu thin films with thicknesses ~500 nm have been deposited on glass substrate by thermal evaporation technique at room temperature. After deposition, these films have been annealed at 200°C for 10 - 40 minutes. The thickness and annealing effect on the structural and morphological properties were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM) respectively. The results showed that by increasing thickness the copper films crystallinity in (111) direction had been increased. Also by varying the annealing time the significant changes were observed in the films crystallinity and surface morphology.

Trichloroethylene (TCE) is found in all mediums of environment in varying concentrations. Over the past 25 years, many engineered systems have been devised for its complete and sustainable degradation. This study reviews the environmental factors that influence the TCE pollution in environment and its biological mineralization via engineered systems. Although at some polluted sites natural attenuation of TCE has been found to occur but generally the natural process is very slow. The use of nanoparticles and composites provides a comparatively novel approach for the treatment of TCE contaminated waters. Biological engineered systems have been found to degrade TCE on much faster rates and higher concentrations. To identify the appropriate microorganisms in any engineered system that can effectively provide a low-cost treatment option for TCE degradation is the pressing need at the moment. Adding a second distinct organic phase to the aqueous medium for degrading fast and high concentration of TCE is recommended. The organic phase, which do not mix with the aqueous phase and can be easily separated, discharged, and reuse, should be selected based on its insolubility, volatility, non-biodegradability by the selected microorganism and the cost of the overall engineered system. Biodegradation offers the potential of cost effective treatment of TCE, however, that engineered systems should effectively use the biodegradative metabolism that nature has evolved.

Arsenic contamination of groundwater in many nations including Bangladesh shows that this is a global problem. Because of the delayed health effects, poor reporting, and low levels of awareness in some communities, the extent of the adverse health problems caused by arsenic in drinking water is at alarming level in Bangladesh. Also, allocating resources such as tube wells efficiently and effectively to mitigate arsenic hazard is a challenging task in Bangladesh. To allocate resources based on different arsenic hazard parameters, we have developed a Decision Support System that enables the user to observe the effect of allocation policy both in tabular and spatial format using statistical models. We have also developed an algorithm for optimal allocation of resources. A Smart User Interface is designed for the users so that they will find an interactive, user-friendly, intelligible, logical, clear, and sound environment to work with. Finally, we have analyzed and demonstrated the efficacy of our algorithm graphically.

Polyamide-6-based composites with pristine or functionalized multi-walled carbon nanotubes were produced using melt extrusion technique. After chemical functionalization, defect formation and attachment of carboxylic (−COOH) or amine (−NH2) groups on carbon nanotubes was confirmed from high-resolution transmission electron microscope and Fourier transform infra-red spectroscope studies. Carbon nanotubes incorporation promoted growth of α-form crystals with enhanced thermal stability through increase in crystallization temperature from 162 to 192℃. Dynamic mechanical thermal analysis (DMTA) indirectly pointed out to a homogeneous, uniform dispersion of nanotubes with reduction in free volume of the polymer, exhibiting a slight increase in glass transition temperature and a significant drop in coefficient of thermal expansion value. Composites containing 0.5 wt% NH2-carbon nanotubes show increases in elastic modulus and tensile strength by ∼60 and 76%, respectively. Uniform dispersion and high interfacial strength was manifested by drop in strain to failure and lack of evidence of carbon nanotubes debonding from the matrix.

ZnO thin films were prepared by sol-gel method. Prepared thin films were then characterized by SEM, XRD, EDX and Hall effect measurements. SEM confirmed the morphological studies of ZnO thin films. Crystallite size is calculated using the Scherrer formula. Crystallite and grain sizes are obtained through XRD and SEM. EDS analysis confirms mass percentage of ZnO deposited. Decreasing trend of magneto resistance with temperature is observed. The optical transmission spectra of the sol gel deposited ZnO thin films showed high transmittance (>70%) in the visible region and indicates that the transmittance of ZnO films gradually decreased as the thickness increased. Decreasing trend of resistivity and sheet resistance with thickness are also observed. The IV characterization of ZnO thin films under influence of UV and dark conditions are reported. The dc electrical resistivity data follow the hoping model.

A study of powder structure and its effect on the sintering tendency of certain alumina-based ceramic systems, that is, Al2O3-SiO2 and Al2O3-ZrO2, was carried out to improve their mechanical strength and fracture toughness. The compacting behavior and the sintering characteristics were optimized through control of various parameters such as composition, compaction pressure, sintering temperature, and time. Best densification was obtained for mixtures prepared using very fine and deagglomerated alumina powders.