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
The investigation of the effect of tempering on thermal analysis of
Al-Ti-Si alloy and its composites with MgO and SiC particles was
performed. Thermal analysis was performed before and after
tempering by DSC scan. Optical microscopy was used to identify the
phases and precipitations that may be formed in base alloy and
composites. X-ray diffraction test indicated that the Al3Ti is the main
phase in Al-Ti-Si alloy in addition to form Al5Ti7Si12 phase. Some
chemical reactions can be occurred between reinforcements and
matrix such as MgO.Al2O3 in Al-Ti/MgO, and Al4C3 and Al(OH)3 in
Al-Ti/SiC composite. X-ray florescence technique is used to
investigate the chemical composition of the fabricated specimens.
H
Soils at Al-Koot-Btera were choosen to determine their sedimentary
environments. It is found that there are , five soil series and as mentioned :
MF11-MW9-DM97-DM57-DF95 . The five found soil series are of internal
well drained ,moderate and imperfect. Their textures vary in moderately,fine
and moderately fine.
indicating that sediments rang from poorly to very poorly sorting. Values of median
diameter Md Ø range between 4.11-7.80 Ø .The relation between the sorting
and median diameter shows that 95.24% of samples is a sedimentary
environment of aquite river , while 4.76% is aeolian sediments.
The values of meso to platy kurtic of most horizon materials rang
between 0.67-1.26 Ø .That is to say the samples
In this study, genetic algorithm was used to predict the reaction kinetics of Iraqi heavy naphtha catalytic reforming process located in Al-Doura refinery in Baghdad. One-dimensional steady state model was derived to describe commercial catalytic reforming unit consisting of four catalytic reforming reactors in series process.
The experimental information (Reformate composition and output temperature) for each four reactors collected at different operating conditions was used to predict the parameters of the proposed kinetic model. The kinetic model involving 24 components, 1 to 11 carbon atoms for paraffins and 6 to 11 carbon atom for naphthenes and aromatics with 71 reactions. The pre-exponential Arrhenius constants and a
... Show MoreIn this study, the four tests employed for non-linear dependence which is Engle (1982), McLeod &Li (1983), Tsay (1986), and Hinich & Patterson (1995). To test the null hypothesis that the time series is a serially independent and identical distribution process .The linear structure is removed from the data which is represent the sales of State Company for Electrical Industries, through a pre-whitening model, AR (p) model .From The results for tests to the data is not so clear.
The educational function of television is one of the basic functions in light of the technical development that included the specialized satellite channels in all its fields, including the educational field, as its role became parallel to the role of educational institutions. These studies are among the descriptive studies in terms of the type of study methodology that describes the phenomenon, interprets its and extract the results and relationships between the variables. The study sample was multistage (random and intentional) included the students of the sixth academic and literary preparatory stage in the city of Baghdad.
The study problem was summarized by the following main question:
( What are the motives for the exposure of
Abstract
The current research problem includes a variety of research motivations to serve the private health sector, which is witnessing a great competition from internal and external environments. In this regard, private medical clinics are increasingly seeking to attract and retain customers through the quality of their service offerings represented by health services. Innovative and effective marketing methods to improve performance and stay in competition, by relying on the physical evidence of the product as a component of the marketing mix of services and its role in particular in packaging and supporting the health service with concrete evidence that affects the customer an
... Show MoreBackground: Pressure ulcers remain a serious complication for immobile patients and a burden for healthcare professionals. Objectives: To assess health behavior prevention among critical care nurses regarding pressure ulcer prevention for hospitalized patients and to find out the relationship between critical care nurses health behavior prevention and sociodemographic variables. Methods: A cross-sectional design study was carried out in critical care units at three teaching hospitals. The study period extended from November 1, 2022, to January 28, 2023. Non-probability purposive sampling, whose target population was 100 nurses who work in critical care units in Baghdad, Iraq. The data were collected using a self-administered questio
... Show MoreHydraulic fracturing is considered to be a vital cornerstone in decision making of unconventional reservoirs. With an increasing level of development of unconventional reservoirs, many questions have arisen regarding enhancing production performance of tight carbonate reservoirs, especially the evaluation of the potential for adapting multistage hydraulic fracturing technology in tight carbonate reservoirs to attain an economic revenue.
In this paper we present a feasibility study of multistage fractured horizontal well in typical tight carbonate reservoirs covering different values of permeability. We show that NPV is the suitable objective function for deciding on the optimum number