In this research the effect of cooling rate and mold type on mechanical properties of the eutectic
and hypoeutectic (Al-Si) alloys has been studied. The alloys used in this research work were (Al- 12.6%Si
alloy) and (Al- 7%Si alloy).The two alloys have been melted and poured in two types of molds with
different cooling rates. One of them was a sand mold and the other was metal mold. Mechanical tests
(hardness, tensile test and impact test) were carried out on the specimens. Also the metallographic
examination was performed.
It has been found that the values of hardness for the alloys(Al-12.6%Si and Al-7%Si) which poured in
metal mold is greater than the values of hardness for the same alloy when it poured in a heated metal
mold at different temperatures or in sand mold. The strength and impact resistance for the alloys (Al-
12.6%Si and Al-7%Si) are greater when these were poured in a metal molds than that when it poured in a
sand mold.
Furthermore, the higher cooling rates enhance the strength, hardness and impact resistance for the
two alloys, while the low cooling rates reduces these mechanical properties.
The percentage of elongation and the amounts of formed porosity decreased when the cooling rates
increased
Aspergillus fumigatus considered to be the most important species to cause respiratory infection cases in both humans and animals especially in cats in the last decades. In this study, we focused on the isolation and identification of Aspergillus fumigates by collecting 40 samples in deferent veterinary clinics and stray cats in Baghdad city, during the period (October 2021 to January 2022), all samples were cultured on Sabouraud dextrose agar and malt extract agar. The isolates identified by the laboratory methods, it’s depend on macroscopic and microscopic appearance. The results showed that (40) swaps taken from the pharynx of infected cats, included: Aspergillus fumigatus 16 (40%), Aspergillus spp. 7 (17.5%), Aspergillus niger
... Show MoreSubjects took physical fitness for health imposed on the area of research that have become an important and clear answer to the many problems resulting from the nature of dealing with modern life current actions that were needed to be hours of manual work has become accomplished by modern technology circumstance minutes, and mediated equipment And machinery. The lack of traffic rights and further burdens the intellectual and psychological pressures and the typical method of work has led to the identification of kinetic activity, thereby threatening public health in many ways stands at the forefront of these threats the problem of smoking, which causes many types of cancers, notably lung cancer. The most important reasons that led to This dr
... Show MoreBackground: Understanding the pathogenesis and molecular basis of Oral Squamous Cell Carcinoma (OSCC) has increased rapidly over the past few years that is essential to improve patient's prognosis and treatment modalities. The purpose of this study to evaluate the Immunohistochemical expressions of AKT, ATM, AND Cyclin E in oral squamous cell carcinoma Materials and methods: This study was performed on a forty formalin-fixed paraffin-embedded blocks which histopathologically diagnosed as Oral Squamous Cell Carcinoma. All cases were collected from the Histopathological Laboratory from patients treated surgically at Maxillofacial surgery Department at Ramadi Teaching Hospital, Iraq. Results: The immunohistochemical staining of AKT showed pos
... Show MoreRasheed Street has had great importance by the nature of what was seen as being of vital events of a key facility in the Iraqi capital Baghdad since ancient times until now .
And such as cultural and historical memory-rich street for Iraq, pulsating nerve since the beginning of the last century thanks to the commercial and intellectual stature, as well as being a tourist landmark frequented alleys most of the tourists coming to Iraq , which counted for them a source of tourist attraction, given the religious diversity of fungal who excelled by the street, as we find in exchange for his Church of the Virgin Mary, the time which was built in the middle of the Caliphs Mosque towering minarets and promised that the oldest and largest of t
Our scientists Arabs old efforts in achieving texts that led to the foundations of general
rules they have set for this work in accordance with the systematic context is based on the
study, analysis and precision in dealing with this work, which became the basis for each
investigator to the present day, which was to them careful consideration manuscripts and
work to be closer to the image by its author, so produced their efforts in this area several
books provided the technical wizards of this science, which did not leave a gap in which only
gave her treatments and suggestions each and every one of the point made by and gave her
what produced the expertise in this direction in accordance with the formulations
meth
The research involves preparing gold nanoparticles (AuNPs) and studying the factors that influence the shape, sizes and distribution ratio of the prepared particles according to Turkevich method. These factors include (reaction temperature, initial heating, concentration of gold ions, concentration and quantity of added citrate, reaction time and order of reactant addition). Gold nanoparticles prepared were characterized by the following measurements: UV-Visible spectroscopy, X-ray diffraction and scanning electron microscopy. The average size of gold nanoparticles was formed in the range (20 -35) nm. The amount of added citrate was changed and studied. In addition, the concentration of added gold ions was changed and the calibration cur
... Show MoreCryptosporidiosis is an intestinal protozoan parasitic disease that infects human and animals, caused by apicomplexan parasite belong to the genusof Cryptosporidium. The current study was done to record the infection rate of cryptosporidiosis in human and cattle, and genotype the clinical isolates of Cryptosporidium in Baghdad Province. A total of 265 stool sample were collected (150 from human and 115 from cattle) during the period from December 2016 to the May 2017. Cryptosporidial infection was detected using modified acid fast stain. DNA of the parasite was extracted from oocysts of positive fecal samples and nested PCR method was used for partial 60 kDa glycoprotein (gp60) gene amplification then sequence analysis for selected samples.
... Show MoreThe ligand Schiff base [(E)-3-(2-hydroxy-5-methylbenzylideneamino)- 1- phenyl-1H-pyrazol-5(4H) –one] with some metals ion as Mn(II); Co(II); Ni(II); Cu(II); Cd(II) and Hg(II) complexes have been preparation and characterized on the basic of mass spectrum for L, elemental analyses, FTIR, electronic spectral, magnetic susceptibility, molar conductivity measurement and functions thermodynamic data study (∆H°, ∆S° and ∆G°). Results of conductivity indicated that all complexes were non electrolytes. Spectroscopy and other analytical studies reveal distorted octahedral geometry for all complexes. The antibacterial activity of the ligand and preparers metal complexes was also studied against gram and negative bacteria.