Texture evolution and fraction of favorably oriented fibers in commercially pure aluminum processed to 16 ECAP passes

Texture evolution in 1050 commercial purity aluminum severely deformed by equal channel angular pressing (ECAP) is investigated by electron back scattered diffraction (EBSD). Pole figures and orientation distribution function (ODF) plots are generated for samples processed to 1, 2, 4, 8, 12 and 16 passes. The processing was done using route B_C, in which the samples were rotated by 90° in the same sense between subsequent pressings. Two different sized scans were performed on the flow plane of the processed samples. The orientations constituting the favorably oriented fibers are depicted and crystal orientation maps are generated. The spatial distribution of grains having these orientations are revealed through these maps. The fraction of the main texture fibers for a 5° spread around the specified orientations is experimentally calculated and a quantitative idea on the evolution of texture is presented. The results ascertained that the texture intensity around the main fibers generally weakens with number of ECAP passes.     

Adsorption desalination of chloride ions on composite natural–synthetic materials: An approach for the reduction of chlorine corrosion in electrodeionization units

The release of chlorine in the electrodeionization (EDI) unit causes corrosion in the EDI unit, damaging ion exchange membranes and creating a safety risk for the workers. In this work, adsorption desalination of Cl^? ions on low-cost composite synthetic–natural Jordanian materials were investigated as an approach to prevent the release of corrosive chlorine gas at the positive electrode. The percentage removal reaches 25% at 25 min shaking time to 55% at 120 min, in a single batch experiment. The values of ΔH⁰, ΔS⁰, and ΔG⁰ indicate the favorability of physisorption. Zeolite and Pozzolana represent potential adsorbents of chloride.     

Effects of Plasticizers，Antioxidants and Burning Rate Modifiers on Aging Performance of the HTPB/ HMDI Composite Solid Propellant

The effects of plasticizers,antioxidants and burning rate modifiers on the aging performance of the composite solid propellant based on hydroxyl-terminated polybutadiene(HTPB)/hexamethylene diisocyanate(HMDI)were explored by apply-ing an accelerated aging program for 90 day at 70 ℃. The HTPB propellant matrix with the diisooctyl sebacate(DOS)as plasti-cizers and diisooctyl azelate(DOZ), antioxidants as N,N ′-Diphenyl-p-phenylenediamine(AO) and 2,2′-methylenebis(4-methyl-6-tert-butylphenol)(cyanox 2246)and burning rate modifiers as barium ferrite(BF),copper chromites(CC)and fer-ric oxide(FO)were varied. Results show that sample(S1)which based on DOS decreases the stress value and increases the strain value which considered to be an excellent start for aging program. Sample(S3)containing AO presents the higher resis-tance to oxidation showing the better performance that reflects on increasing the shelf life of the composite solid propellant mo-tor. Sample(S5)which based on BF enhances the ballistic performance among over the other tested two samples. The accelerat-ed aging program allowed us to estimate the motor in-service lifetime.     

Maximizing lifetime of large-scale wireless sensor networks using multi-objective whale optimization algorithm

Telecommunication Systems - The sink nodes in large-scale wireless sensor networks (LSWSNs) are responsible for receiving and processing the collected data from sensor nodes. Identifying the...     

Synthesis of mordenite zeolite in absence of organic template

Mordenite is a zeolite that has been used as a selective adsorbent and as a catalyst. Mordenite zeolite with crystal diameter 65 nm and crystal length 7 μm was successively synthesized in the absence of organic template by hydrothermal method at 180 °C for 5 days after stirring at high speed and aging in the synthesis mixture with the molar composition of 12Na₂O:100SiO₂:2Al₂O₃:500H₂O. The produced samples were investigated using XRD, SEM, FT-IR, EDS, DTA/TG and BET surface area. The prepared sample, crystallized in needle shape crystals. Total (BET) surface area was 52.14 m²/g whereas, total pore volume was 0.2 cm³/g. Average pore diameter was 24.16 Å. Thermogravimetry analysis (DTA/TG) showed that, at room temperature to 800 °C, mordenite mass loss is 6%.     

Construction and Testing of an Innovative Concrete Bridge Deck Totally Reinforced with Glass FRP Bars: Val-Alain Bridge on Highway 20 East

The Val-Alain Bridge, located in the Municipality of Val-Alain on Highway 20 East, crosses over Henri River in Québec, Canada. The bridge is a slab-on-girder type with a skew angle of 20° over a single span of 49.89?m and a total width of 12.57?m. The bridge has four simply supported steel girders spaced at 3,145?mm. The deck slab is a 225-mm-thick concrete slab, with semi-integral abutments, continuous over the steel girders with an overhang of 1,570?mm on each side. The concrete deck slab and the bridge barriers were reinforced with glass fiber reinforced polymer (GFRP) reinforcing bars utilizing high-performance concrete. The Val-Alain Bridge is the Canada’s first concrete bridge deck totally reinforced with GFRP reinforcing bars. Using such nonmetallic reinforcement in combination with high-performance concrete leads to an expected service life of more than 75?years. The bridge is well instrumented with electrical resistance strain gauges and fiber-optic sensors at critical locations to record internal strain data. Also, the bridge was tested for service performance using calibrated truckloads. Design concepts, construction details, and results of the first series of live load field tests are presented.