The earth-air heat exchanger (EHX) has a promising potential to passively save the energy consumption of traditional air conditioning systems while maintaining a high degree of indoor comfort. The use of EHX systems for air conditioning in commercial and industrial settings offers several environmental benefits and is capable of operating in both standalone and hybrid modes. This study tests the performance and effectiveness of an EHX design in a sandy soil area in Baghdad, Iraq. The area has a climate of the subtropical semi-humid type. Ambient air temperatures and soil temperatures were recorded throughout the months of 2021. During the months of January and June, the temperatures of the inlet and outflow air at varying air velocities were monitored concurrently in 10-min increments at each location. Further numerical and thermodynamical analyses of the measurements were conducted to reveal the influencing performance parameters. The highest temperature rises of air between the input and exit sections were determined as 12.3°C (January) and 17.2°C (June). It is found that the maximum values of effectiveness are 0.80 and 0.81, while coefficients of performance are 1.6 and 1.8 for January and June, respectively. It is also found that the EHX shows good functionality and effectiveness, with potential energy savings for equipment for cooling and heating under different weather conditions.
Background: Denture cleansing was an important step that could prevent the spread of infection and improve a patient's health, the durability of the dentures, and the overall quality of life; therefore, it was necessary to choose a suitable cleanser that, in addition to being effective, did not have an unfavorable effect on the qualities of the denture base resin itself when used for an extended period. For this purpose, this study aimed to evaluate the effect of tea tree oil (TTO) on Candida albicans adhesion and the surface roughness property of poly(methyl methacrylate) denture material after immersion in TTO. Methods: A total of 55 heat-cured acrylic resin specimens were used for C. albicans adherence and surface roughness tests. The
... Show MoreAmino acids have the role in the process of proteins synthesis. They are an essential source of nitrogen atoms that have a role in the pathways of synthetic reaction pathways. The carbon skeletons of the amino acids are the source of energy in addition to their role as precursors in the paths of interactions. The amino acids analysis for the brain of the quail bird in different stage of development (10-16 days of incubation) in addition to the hatching stage (17th day) and the adult. Materials and Methods: Amino Acids Analysis The amino acids were separated from the embryos and adult brains of the quail bird Coturnix coturnix and were diagnosed based on standard amino acids, using high performance liquid chromatographic device (H.P.L.C.). R
... Show MoreThe process of granting loans by banks is the confidence they give to their customers, but this trust should not be a cornerstone in granting loans even if granted these loans on the basis of sound banking should involve risks that may be exposed to the bank because of the failure of the client to meet The bank's financial obligations to the bank due to the unexpected economic conditions affecting the customers, which makes them in a state of faltering, which weaken the ability of banks to provide loans, which are the most important sources of revenue and profits, so the problem of non-performing loans is one of the main problems facing most of the banks Which impede the functioning of its work and the reasons that led to the agg
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Codes of red, green, and blue data (RGB) extracted from a lab-fabricated colorimeter device were used to build a proposed classifier with the objective of classifying colors of objects based on defined categories of fundamental colors. Primary, secondary, and tertiary colors namely red, green, orange, yellow, pink, purple, blue, brown, grey, white, and black, were employed in machine learning (ML) by applying an artificial neural network (ANN) algorithm using Python. The classifier, which was based on the ANN algorithm, required a definition of the mentioned eleven colors in the form of RGB codes in order to acquire the capability of classification. The software's capacity to forecast the color of the code that belongs to an ob
... Show MoreCodes of red, green, and blue data (RGB) extracted from a lab-fabricated colorimeter device were used to build a proposed classifier with the objective of classifying colors of objects based on defined categories of fundamental colors. Primary, secondary, and tertiary colors namely red, green, orange, yellow, pink, purple, blue, brown, grey, white, and black, were employed in machine learning (ML) by applying an artificial neural network (ANN) algorithm using Python. The classifier, which was based on the ANN algorithm, required a definition of the mentioned eleven colors in the form of RGB codes in order to acquire the capability of classification. The software's capacity to forecast the color of the code that belongs to an object under de
... Show MoreSeveral stress-strain models were used to predict the strengths of steel fiber reinforced concrete, which are distinctive of the material. However, insufficient research has been done on the influence of hybrid fiber combinations (comprising two or more distinct fibers) on the characteristics of concrete. For this reason, the researchers conducted an experimental program to determine the stress-strain relationship of 30 concrete samples reinforced with two distinct fibers (a hybrid of polyvinyl alcohol and steel fibers), with compressive strengths ranging from 40 to 120 MPa. A total of 80% of the experimental results were used to develop a new empirical stress-strain model, which was accomplished through the application of the parti
... Show MoreSewage water is a mixture of water and solids added to water for various uses, so it needs to be treated to meet local or global standards for environmentally friendly waste production. The present study aimed to analyze the new Maaymyrh sewage treatment plant's quality parameters statistically at Hilla city. The plant is designed to serve 500,000 populations, and it is operating on a biological treatment method (Activated Sludge Process) with an average wastewater inflow of 107,000m3/day. Wastewater data were collected daily by the Mayoralty of Hilla from November 2019 to June 2020 from the influent and effluent in the (STP) new in Maaymyrh for five water quality standards, such as (BOD5), (COD), (TSS), (TP)
... Show MoreTo limit or reduce common microbial contamination occurrence in dairy products in general and in soft cheese in particular, produced in locally plants, this study was performed to demonstrate the possibility of implementing HACCP in one of dairy plants in Baghdad city
HACCP plan was proposed in soft cheese production line. A pre-evaluation was performed in soft cheese line production, HACCP Pre-requisites programs was evaluated from its presence and effectiveness. The evaluation was demonstrated risk in each of: Good Manufacturing Practice (GMP) program, evaluated as microbial and physical risk and considered as critical r
... Show MoreA simple, economic, rapid, reliable, and stability-indicating high-performance liquid chromatography (HPLC) method has been developed and validated for the simultaneous determination of paracetamol (PCM) and caffeine (CF) in solid dosage form. The chromatographic separations were achieved with a Waters Symmetry® C18 column (5 μm, 4.6 × 150 mm), using a mixture of methanol and water (40:60, v/v) as a mobile phase, under isocratic elution mode with a flow rate of 0.8 mL/min, and ultraviolet (UV) detection was set at 264 nm. The oven temperature for the column was set and maintained at 35 °C. The method was validated according to International Conference on Harmonization (ICH) guidelines, and it demonstrated excellent linearity, wi
... Show MoreThe research sought to identify the objective trends of postgraduate students at the College of Political Science - University of Baghdad for the period from 2000-2012 through the objective trends of university theses and dissertations and what are the most and least studied topics, with a re-adjustment of previously studied topics towards topics that serve issues of concern to society and avoiding topics that have been studied a lot to avoid repetition. The research came out with the following results, the most prominent of which are: The total number of what was accomplished in this college is 401 theses and dissertations, and the dissertations had the largest share of them, as their percentage reached 69%, with 275 theses compared to 126
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