A metal-assisted chemical etching process employing p-type silicon wafers with varied etching durations is used to produce silicon nanowires. Silver nanoparticles prepared by chemical deposition are utilized as a catalyst in the formation of silicon nanowires. Images from field emission scanning electron microscopy confirmed that the diameter of SiNWs grows when the etching duration is increased. The photoelectrochemical cell's characteristics were investigated using p-type silicon nanowires as working electrodes. Linear sweep voltammetry (J-V) measurements on p-SiNWs confirmed that photocurrent density rose from 0.20 mA cm-2 to 0.92 mA cm-2 as the etching duration of prepared SiNWs increased from 15 to 30 min. The conversion efficiency (ƞ) was 0.47 for p-SiNWs prepared with a 15-minute etching time and 0.75 for p-SiNWs prepared with a 30-minute etching time. The cyclic voltammetry (CV) experiments performed at various scan rates validated the faradic behavior of p-SiNWS prepared for 15 and 30 min of etching. Because of the slow ion diffusion and the increased scanning rate, the capacitance decreased with increasing scanning rate. Mott-Schottky (M-S) investigation showed a significant carriers concentration of 3.66×1020 cm-3. According to the results of electrochemical impedance spectroscopy (EIS), the SiNWs photocathode prepared by etching for 30 min had a charge transfer resistance of 25.27 Ω, which is low enough to enhance interfacial charge transfer.
Highway embankments stability during its service period represents an important factor for the safety of highway users and vehicles. Consequently, the cost of construction of these embankments should be adequate to maintain the safety and durability during this period through proper estimation of the loading on asphalt pavement, slope stability, horizontal and vertical deformation, etc. Slope stability of the embankment mainly depends on the shear strength of the soil layers materials; this shear strength is affected by the water table level through the contribution of the capillary water. Negative pore water pressure above the water table level evolves matric suction in the unsaturated zone above water table; this matric suction increases
... Show MoreIn the present work, asphaltenes and resins separated from emulsion samples collected from two Iraqi oil wells, Nafut Kana (Nk) and Basrah were used to study the emulsion stability. The effect of oil resins to asphaltene (R/A) ratio, pH of the aqueous phase, addition of paraffinic solvent (n-heptane), aromatic solvent (toluene), and blend of both (heptol) in various proportions on the stability of emulsions had been investigated. The conditions of experiments were specified as an agitation speed of 1000 rpm for 30 minutes, heating at 50 °C, and water content of 30%. The results showed that as the R/A ratio increases, the emulsion will be unstable and the amount of water separated from emulsion increases. It was noticed that the em
... Show MoreThe study was conducted to investigate the effect of salinity of irrigation water on seeds quality and seedling growth characters for three oat cultivars (Shifaa, Hamel and Pimula) . It was carried oat in seed technology laboratory, field crops department, College of Agriculture, Baghdad University of Aljadiriya for period of tow years. Seeds of three oat cultivars (Shifaa, Hamel and Pimula) taken from a field experiment conducted during 2014-2015 and 2015-2016 irrigated with three salinity water levels (3, 6 and 9 dS.m-1 ) in addition to river water with salinity level of 1.164 dS.m-1 as control. Seeds were tested in laboratory experiments to estimate their quality, and completely randomized design with three replicates was used. Statistic
... Show MoreThe study addressed the water ecosystems of the marshes of Maysan Governorate as one of the important areas in Iraq in terms of the environmental, economic and tourism aspects. This area was exposed to great environmental changes due to natural and human factors which greatly affected the water ecosystem and made the area susceptible to many problems that affected the biological life of living organisms. The marshes of Maysan Governorate was affected by vital factors and non-vital factors. The marshes of Maysan Governorate was characterized by the UN Organization as one of the most important centers of biodiversity in the world because of the abundance of different and rare living organisms such as birds, fish, and reptiles as well as the e
... Show MoreRates of zinc consumption during cathodic protection of a copper pipeline carrying saline water were measured by the loss in weight technique. The study of sacrificial anode cathodic protection of short copper tube using zinc strip extended axially in the pipe revealed that : (i) The increase of zinc consumption with time of exposure (1-3 h's) at different flow rates (turbulent flow) (300-600 l/hr) while the temperature , solution concentration and the pH were fixed at 20ºC, 3.5%wt NaCl, and pH=8 respectively in absence and presence of bacteria.(ii)Increase of zinc consumption with flow rates (300-600 l/hr) at different temperatures (10-40ºC) while solution concentration and time of exposure were fixed at 3.5 %wt NaCl and 3hr's respect
... Show More