The research targets study of influence of additives on sand mold’s properties and, consequently, on
that of carbon steel CK45 casts produced by three molds. Three materials were selected for addition
to sand mix at weight percentages. These are sodium carbonates, glycerin and oat flour. Sand molds
of studied properties were produced to get casts from such molds. The required tests were made to
find the best additives with respect to properties of cast. ANSYS software is used to demonstrate
the stresses distribution of each produced materials. It is shown that the mechanical properties of
casts produced is improved highly with sodium carbonates and is less with oat flour and it is seem a
few with glycerin additives. It can be concluded that the sodium carbonates let to get the cast
produced with highly mechanical properties.
This study was designed to evaluate the antimicrobial effect of Cymbopogon citratus and Mentha spicata essential oils, separately and mixed, against the microorganisms in yogurt, as well as study the possibility of these essential oils (EO) as natural preservatives and flavors additives/enhancers in yogurt product. Yogurt samples were treated with lemongrass and spearmint EOin different concentrations (250, 500, 1000 ppm: 6250µg/50 ml yogurt, 12500 µg/50 ml yogurt and 25000 µg/50 ml yogurt respectively). The control and treated samples were preserved both at room (25°C) and refrigerator (5°C) temperatures. In control, the contamination was observed through 2 weeks at 25°C and for about one month at 5°C
... Show MoreThis work study the effect of laser surface heat treatment on physical properties (green density, density after sintering, theoretical density and porosity)of a composite material of an Al powder as a matrix with different percentage of B4C powder as additive material. This work was done by two stages: First stage: Production the maincomposite material which is contain Al powder with grain size 24μm as a matrix and B4C powder with grain size 50μm as additive with different weight percentage (5%,10%,15%,20%,25%,30%), and the powders Maxined for suitable time 15min, after that the mixture compacted with 2ton and sintered at 550C0. Second stage: Laser surface treatment was done for the productive composite material after sintering by usin
... Show MoreIn the recent years, some of the newly constructed asphalt concrete pavements in Baghdad as well as other cities across Iraq showed premature failures with consequential negative impact on both roadway safety and economy. Frequently, load associated mode of failure (rutting and fatigue) as well as, occasionally, moisture damage in some poorly drained sections are the main failure types found in those newly constructed road.
In this research, hydrated lime was introduced into asphalt concrete mixtures of wearing course in two methods. The first one was the addition of dry lime on dry aggregate and the second one was the addition of dry lime on saturated surface dry aggregate moisturized by 2.0 to 3.0 percent of wa
... Show MoreBulk polycrystalline samples have been prepared by the two-step solid state reaction process. It has been observed that as grown Tl2-xHgxSr2Ca2Cu3O10+δ (with x = 0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.8, 1) corresponds to the 2223 phase. It has been found that Tc varies with Hg content .The optimum Tc is about 120K for the composition Tl1.6Hg0.4Sr2Ca2Cu3O10+δ.The microstructure for Tl1.6Hg0.4Sr2Ca2Cu3O10+δ observed to be most dense and this phase exhibits the highest stability.
The nanocomposite on the base of synthesis Copper iodide
nanoparticles and polyvinyl alcohol (PVA/CuI) with different
concentration of CuI were obtained using casting technique.
PVA/CuI polymer composite samples have been prepared and
subjected to characterizations using FTIR spectroscopy, The FTIR
spectral analysis shows remarkable variation of the absorption peak
positions with increasing CuI concentration. The obtained results by
X-ray diffraction indicated the formation of cubic CuI particles. The
effects of CuI concentrations on the optical properties of the PVA
films were studied in the region of wavelength, (190-1100) nm.
From the derivation of Tauc's relation it was found that the direct
allowed t
This study was conducted in the Faculty of Agricultural Engineering Sciences - University of Baghdad in the field of sheep and goats in the Department of Animal Production. Effect of different concentrations of bovine albumin on some semen characteristics of frozen rams. Used in this experiment, 3 rams and their ages ranging from 2.5-3 years. The sample of the semen was diluted with Tris dilution with the addition of 10 ml of egg yolk per 100 ml, the sample by 1:1 with the tris and then the collection of sperm samples (Pooling) after the semen was divided into four treatments Control and bovine albumin at concentrations of 5, 7.5 and 10% and then complete dilution 10: 1, at 5C, dilution 20: 1, containing 5% glycerol per 100 ml. The results
... Show MoreOptical fiber technology is without a doubt one of the most significant phases of the communications revolution and is crucial to our daily lives. Using the free version (2022) of RP Fiber Calculator, the modal properties for optical fibers with core radii (1.5−7.5) μm, core index (1.44−1.48) and cladding index (1.43−1.47) have been determined at a wavelength of 1000 nm. When the fiber core’s radius is larger than its operating wavelength, multimode fibers can be created. The result is a single-mode fiber in all other cases. All of the calculated properties, it has been shown, increase with increasing core radius. The modes’ intensity profiles were displayed.
Tool wear is a major problem in machining operations because the resulting material loss gradually changes of the machine tool. There many factors may leads to material loss like; friction, corrosion, and also it’s happened by rubbing during machining processes between the work piece and the tool. Dimensional accuracy of the work piece, and also the surface finish will be reducing by tool wear. It can also increase cutting force. In this study, we focused on the effect of the coating process on crater wear problems. Crater wear is caused by the flow between the chip and the rake face of the tool, whereas flank wear is caused by the contact between the tool and the work piece. In reducing crater wear, aluminum titanium nitride (AlTiN) u
... Show MorePM3 and Unrestricted Hartree Fock (UHF) quantum mechanical methods are carried out for the estimation of reaction path for the breakage of (R-O) bond rupture energies, for twelve ampicillin ester prodrugs derivatives, at their calculated equilibrium geometries, in addition to some physical properties such as heat of formation, total energy, dipole moment and the energy difference of EHOMO and ELUMO (ΔEHOMO-LUMO) energy levels, using the Gaussian-03 program. Comparisons were done between the total energies of the reactants, products, activation energies and transition states. The results show non possible use of some substituted organic groups as a carrier linkage for acidic ampicillin drug, whereas others show possible use as a carrier
... Show MoreQuantum mechanical computations is conducted using DFT (Density Functional Theory) and PM3 (Parameterized Model 3), also, using DFT of (B3LYP) with a 6-311++G (d, p) with G09 application. These molecular three components include structure, electronic charge density and energetic characteristics of chosen phytomedicine compounds. The impact of functional groups on physical characteristics were studied using myricetin, linebacker, and flavone because of their chemical structures. For phytomedicine compounds, we utilized quantum mechanical simulations to estimate bond length, energy, vibration(vib.) modes, charge density and mechanical properties (cruelty, strength, stiffness, for the measurements of the lengths and energy of the
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