Copper and Zinc powders with different particle sizes were subjected to sieving of range (20-100?m) and He-Ne laser system to determine the particle size . 1wt% from each powders was blended carefully with 99wt% from Iraqi oil . Microscopic examination were carried for all samples to reveal the particle size distribution . XRF intensity measurements were conducted for all suspended samples , and the relation between XRF intensity and the particle size was found .
Heat transfer performance of two horizontal parallel plates subjected to discrete heating from the upper plate is studied and analyzed under the condition of different gap size between the heating elements with water as the working fluid. The investigation includes the variation of Reynolds number and the heat flux along with the position of the heating elements to discover the effect of different boundary conditions on the gap size variation. Results show that gap size between the heating elements has a crucial impact on the heat transfer process inside the channel, when the gap size increased a remarkable enhancement is achieved. This result is also confirmed with the investigated range of Reynolds number and the heating value. Results al
... Show MoreThis study was conducted at the Research Experimental Station of the College of Agricultural Engineering/University of Baghdad in the Al-Jadiriyah area during the autumn season of 2022. The study aimed to investigate the effect of phosphorus addition and zinc spraying on the nutrient content and root growth of the cabbage. The experiment included two factors: the first factor was phosphorus with four concentrations (P25%, P50%, P75%, and P100%) of the recommended complete fertilizer dose (135 kg P2O5 per hectare), and the second factor was zinc spraying with three concentrations (0, 30, and 60 mg.L-1) of zinc sulfate (ZnSO4). The results showe
In the present work effect of recycled heating and cooling on the values of concrete compressive strength due to high temperature of 4000C was studied.
The tests show that the percent of reduction in compressive strength of the samples which exposed to a temperature of 4000C for one cycle was 32.5%, while the reduction was 52.7% for the samples which were exposed to recycled heating and cooling of ten times .
Moreover a study of the effect of specimen sizes on the percentages of compressive strength reduction due to high temperature
... Show MoreIn this work, the effect of aluminum (Al) dust particles on the DC discharge plasma properties in argon was investigated. A magnetron is placed behind the cathode at different pressures and with varying amounts of Al. The plasma temperature (Te) and density (ne) were calculated using the Boltzmann equation and Stark broadening phenomena, which are considered the most important plasma variables through which the other plasma parameters were calculated. The measurements showed that the emission intensity decreases with increasing pressure from 0.06 to 0.4 Torr, and it slightly decreases with the addition of the NPs. The calculations showed that the ne increased and Te decreased with pressure. Both Te and ne were reduced by increasing
... Show MoreBackground: Alterations in the microhardness and roughness are commonly used to analyze the possible negative effects of bleaching products on restorative materials. This in vitro study evaluated the effect of in-office bleaching (SDI pola office +) on the surface roughness and micro-hardness of four newly developed composite materials (Z350XT –nano-filled, Z250XT-nano-hybrid, Z250-mico-hybrid and Silorane-silorane based). Materials and methods: Eighty circular samples with A3 shading were prepared by using Teflon mold 2mm thickness and 10mm in diameter. 20 samples for each material, 10 samples for base line measurement (surface roughness by using portable profillometer, and micro-hardness by usingDigital Micro Vickers Hardness Test
... Show MoreThe world is keeping pace with evolution in all its fields as a result of scientists' pursuit of continuous scientific and technological development. This evolution included the sports field, which had a large space in the aspect of development and for all disciplines, Therefore, it's reflected today in what we see of records and advanced achievements in sporting events and activities. The development in the field of sports was the result of scientific research (Hussein and Jawad., 2022), where the interest in the training process has become one of the most important pillars of the development of achievement (Neamah and Altay., 2020). The shooting sport has also witnessed a remarkable development due to the diversity and development of its
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