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Herein, aluminum matrix composites were successfully fabricated with friction stir processing using the Al alloy 5083 as the matrix, and Ti3SiC2 MAX phase as the reinforcing particulates. The composites were fabricated using different tool rotational speeds and multi-pass approach. The microhardness and wear resistance of the AA5083/Ti3SiC2 composites were highly related to the processing parameters. The mechanical performance was directly related to the processing defects and particle distribution. Microstructural analysis using optical and scanning electron microscopy revealed that increasing the number of passes results in a more uniform distribution of Ti3SiC2 particles. The composites showed a wear rate reduction by one order of magnitude and a hardness increase from 80 to 140 Hv mean value. The wear mechanism of the AA5083 changed from severe adhesive to predominantly abrasive wear for the AA5083/Ti3SiC2 composites. Ti3SiC2 particles promoted the material transfer from the sliding counterpart; coupled with tribo-oxidation, anti-wear tribo layers were formed. [ABSTRACT FROM AUTHOR]

Muhammad Iqbal’s cultural, literary, and philosophical influence on the Indian subcontinent, especially his impact on the events that led to the birth of the state of Pakistan cannot be denied. Prior to visiting Europe, Iqbāl had gained profound understanding of Islamic teachings. While in Europe, he acquired deep knowledge of Western scholarship and was also exposed to Western philosophical thought, which he acquired from his Western mentors. He synthesized these two worldviews in his own work and thought. The principle concept in Iqbal’s thought is the idea of the self, which he gleaned not only from Islamic sources but also from the works of philosophers such as Schopenhauer, Nietzsche, and Bergson. This paper addresses the influence of these European philosophers on the development of Iqbal’s thought.

Kuwait Bay's southern shore is home to several facilities used for various purposes, impacting the beaches' ecosystems and coastal environment. Furthermore, the presence of numerous stormwater outfalls on Kuwait Bay's southern shores may be one of the sources of pollutants that are discharged from these outfalls. This research aims to evaluate the microbiological quality of seawater near 5 selected stormwater outfalls located on Kuwait Bay's recreational water by measuring the levels of microbial bacteria such as fecal coliform (FC), and Escherichia Coli. (E. Coli), and fecal streptococci (FS), and water quality parameters including temperature, pH, electrical conductivity (EC), and dissolved oxygen (DO). The analytical results were compared with Kuwait Environmental Public Authority (EPA) requirements for water discharge to Kuwait Bay to assess the suitability of the beaches for recreational activities. The field results revealed the presence of mildly alkaline seawater samples, a range of fresh to saline water types, and various DO levels from very low to acceptable levels. noteworthy, the microbial indicators were extremely high and far beyond EPA guidelines, demonstrating extensive microbiological pollution at these locations. The mean FC/FS ratios of C18 had the greatest mean FC/FS ratio (16.75), signifying human contamination. C3 and C5 indicated human waste in mixed pollution with averages of (3.45 and 2.34 respectively), whereas C8 and C10 showed human contamination with average values (of 5.98, and 4.21 respectively). It is suggested that the seawater quality close to wastewater outfalls be frequently evaluated and treated using efficient onsite treatment technologies to decrease the amount of polluted wastewater discharged directly to the beaches. [ABSTRACT FROM AUTHOR]

In this study, wear and friction behavior of two based‐composites from the Ti‐Si‐C system, (40 wt% TiC; 28 wt% Ti5Si3; 17 wt% Ti3SiC2) and (18 wt% TiC; 26 wt% Ti5Si3; 41 wt% Ti3SiC2) reinforced by 15 wt% of large size SiC (100‐150 µm) particles were investigated. The four‐phase composites exhibited approximatively the same friction coefficient (µ ~ 0.9) under high loads (10 N and 7 N). The composite with high Ti3SiC2 showed higher wear rate values by one order of magnitude. However, under 1 N, the composite with high TiC content showed a higher running‐in period and a lower steady state µ value (0.37 after 1000 m sliding distance). Scanning electron microscopy, Energy Dispersive X‐Ray and Raman spectroscopy analysis of the worn surfaces of the two composites revealed that oxidation was the dominant wear mechanism. The oxidation process and the removal kinetics of the oxides during sliding controlled the tribological behavior of the composites. The influence of processing variables on microstructures development and wear mechanisms of the composites is discussed. [ABSTRACT FROM AUTHOR]

A study was carried out to determine the optimum soil depth for the removal of coliphage viruses from treated wastewater. Treated wastewater containing viruses was passed through soil columns filled with soil collected from Sulaibiya area, Kuwait. The soil column experiments were under operation for eight months during the period from August 2004 to March 2005. Three soil depths were used in these experiments. These are 0.1, 0.2, 0.4, and 0.8m of natural Sulaibiya soil. For each experimental condition, two identical columns were set up, so that the changes of the results can be evaluated, producing total of eight columns. For all columns, the coliphage tests were studied only under alternating 1 d flooding and 1 d drying conditions. Influent and effluent coliphage samples were collected and analyzed following cycles of flooding periods. The coliphage virus count in the treated wastewater ranged between 0 and 62,800 pfu/100 ml. The laboratory results revealed that coliphage removal for Sulaibiya soil ranged between 58 and 100% for soil depth of 10 cm, and the viruses were completely removed after passing 20 cm thickness of soil. Also, the results indicated that no virus breakthrough occurred at soil depths of 40 and 80 cm. [ABSTRACT FROM AUTHOR]

A laboratory study was carried out to determine the best domestic water filter with respect to cost, volume of treated water, and effectiveness in improving the quality of potable water. Six types of filters were tested including sand, five micron cartridge, ceramic, carbon block, ultra violet (UV) sterilization unit, and reverse osmosis combined filters. Water samples were collected upstream and downstream of each type of filter. These samples were analyzed for pH, EC, TDS, TSS, turbidity, TOC, chlorine concentration, and various bacteria. Also, the volume of treated water produced by each type of filter was measured. The laboratory results indicated that inlet water had low salinity (TDS value 275–438 mg/l), low TSS (0–7 mg/l), chlorine (0.13–0.78 mg/l) contents, and high content of bacteria (1–1212 MPN/100 ml). The results revealed that the membrane of the RO combined filter set was exposed to severe damage by the residual chlorine in the water, rendering the membrane unable to reduce water salinity effectively and causing high total bacteria counts in the filtered water. Additionally, a biological slime layer formed at the surfaces of cartridge filters, and produced high values of TSS and bacteria in the filtrate samples. The results showed that the best type of filter was the five micron filter on the basis of cost, volume of filtered water, and improvement in water quality. [ABSTRACT FROM PUBLISHER]

Laboratory and field experiments have been carried out to find an optimum method for the treatment of hydrogen sulfide-rich groundwater that often occurs at comparatively shallow depths (15-40m from the surface) in the urban areas of Kuwait City and is pumped to the surface during dewatering of the construction sites. The treatment would be necessary to remove the gas from the pumped groundwater before its disposal, either on the surface or to the stormwater network, to avoid health and environmental hazards created by the release of the hydrogen sulfide gas, which is toxic, to the atmosphere or to the sea. Based on these experiments, it has been recommended that an economic and reliable hydrogen sulfide treatment facility for groundwater pumped at the study area should consist of sand filters, followed by aeration units for the removal of major part (60-70%) of hydrogen sulfide. Chlorination or activated carbon adsorption can be utilized as a polishing process to remove the residual hydrogen sulfide, depending on its concentration in the water after the aeration treatment and the rate of groundwater pumping. [ABSTRACT FROM AUTHOR]

Abstract: The structural properties of polycrystalline silicon films, prepared by plasma enhanced chemical vapor deposition system, with different flow rates of SiH4/SiF4 mixtures at 300°C were investigated. This study indicates that the low hydrogen coverage on the growing surface, under optimum fluorine radicals, will be leaded to an improvement of crystallized area as compared with case of high hydrogen coverage surface. Moreover, the studies of the role of SiH4 and SiF4 radicals show that the SiH4 radicals are important in the nucleation and growth of grains. However, SiF4 radicals are effective in the structural change of grain boundaries regions and by this way, in the present system, establish the growth of grains under the dominant 〈110〉 direction. The stress investigation indicates that addition of high flow rate of SiF4 in amorphous film, results in the nearly stress free films. Finally, we found that the changes in g-value reflect the changes in the intrinsic compressive and tensile stress in the both polycrystalline and amorphous silicon films. [Copyright &y& Elsevier]

Advanced oxidation technologies are a friendly environmental approach for the remediation of industrial wastewaters. Here, one pot synthesis of mesoporous WO 3 and WO 3 -graphene oxide (GO) nanocomposites has been performed through the sol–gel method. Then, platinum (Pt) nanoparticles were deposited onto the WO 3 and WO 3 -GO nanocomposite through photochemical reduction to produce mesoporous Pt/WO 3 and Pt/WO 3 -GO nanocomposites. X-ray diffraction (XRD) findings exhibit a formation of monoclinic and triclinic WO 3 phases. Transmission Electron Microscope (TEM) images of Pt/WO 3 -GO nanocomposites exhibited that WO 3 nanoparticles are obviously agglomerated and the particle sizes of Pt and WO 3 are ~ 10 nm and 20–50 nm, respectively. The mesoporous Pt/WO 3 and Pt/WO 3 -GO nanocomposites were assessed for photocatalytic degradation of Methylene Blue (MB) as a probe molecule under visible light illumination. The findings showed that mesoporous Pt/WO 3 , WO 3 -GO and Pt/WO 3 -GO nanocomposites exhibited much higher photocatalytic efficiencies than the pure WO 3 . The photodegradation rates by mesoporous Pt/WO 3 -GO nanocomposites are 3, 2 and 1.15 times greater than those by mesoporous WO 3 , WO 3 -GO, and Pt/WO 3 , respectively. The key factors of the enhanced photocatalytic performance of Pt/WO 3 -GO nanocomposites could be explained by the highly freedom electron transfer through the synergetic effect between WO 3 and GO sheets, in addition to the Pt nanoparticles that act as active sites for O 2 reduction, which suppresses the electron hole pair recombination in the Pt/WO 3 -GO nanocomposites. [ABSTRACT FROM AUTHOR]