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Theoretical Prediction of Optimum Chilled Water Distribution Configuration in Air Conditioning Terminal Unit
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 The distribution of chilled water flow rate in terminal unit is a major factor used to evaluate the performance of central air conditioning unit. In this work, a theoretical chilled water distribution in the terminal units has been studied to predict the optimum heat performance of terminal unit. The central Air-conditioning unit model consists of cooling/ heating coil (three units), chilled water source (chiller), three-way and two-way valve with bypass, piping network, and pump. The term of optimization in terminal unit ingredient has two categories, the first is the uniform of the water flow rate representing in statically permanents standard deviation (minimum value) and the second category is the maximum heat transfer rate from all terminal units. The hydraulic and energy equations governing the performance of unit solved with the aid of FORTRAN code with considering the following parameters: total water flow rate, chilled water supply temperature, and variable valve opening. It was found that the optimum solution of three-way valve case at 8°C water supply temperature, 0.12 kg/s total water flow rate and valve opening order (valve 1: 100%, valve 2: 100% and valve 3: 75%) with total heat rate (987.92 Watt) and standard deviation (1.181E-3). Also, for the two-way valve case the results showed that the optimum condition at 8°C water supply temperature, 0.12 kg/s total water flow rate and valve opening order (valve 1: 75%, valve 2: 75% and valve 3: 50%) with total heat rate and standard deviation (717Watt) and (5.69E-4) respectively.

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Publication Date
Fri Jun 24 2022
Journal Name
Iraqi Journal Of Science
Theoretical Study of New Derivative of Cefotaxime-Amic Acid as a Corrosion Inhibitor
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PM3 and DFT quantum mechanical calculations were employed to give further
insight into the inhibition efficiency of the newly prepared cefotaxime amic acid
derivative. The calculated physical properties and quantum chemical parameters
correlated to the inhibition efficiency such as EHOMO (highest occupied molecular
orbital energy), ELUMO (lowest unoccupied molecular orbital energy), the energy gap
(ΔE(HOMO-LUMO)), hardness (η), softness (S), dipole moment (μ), electron affinity
(EA), ionization potential (IE) and active site absorption..…etc., all studied and
discussed at equilibrium geometry in the gas phase and at its right symmetry (C1).
Experimentally the newly prepared cefotaxime derivative could be abso

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Publication Date
Fri Sep 01 2023
Journal Name
Energy Reports
Effect of solvents on performance of Alq3/ZnO solar cells: A theoretical approach
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Successfully, theoretical equations were established to study the effect of solvent polarities on the electron current density, fill factor and efficiencies of Tris (8-hydroxy) quinoline aluminum (Alq3)/ ZnO solar cells. Three different solvents studied in this theoretical works, namely 1-propanol, ethanol and acetonitrile. The quantum model of transition energy in donor–acceptor system was used to derive a current formula. After that, it has been used to calculate the fill factor and the efficiency of the solar cell. The calculations indicated that the efficiency of the solar cell is influenced by the polarity of solvents. The best performance was for the solar cell based on acetonitrile as a solvent with electron current density of (5.0

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Publication Date
Fri Jun 24 2022
Journal Name
Iraqi Journal Of Science
Optimum conditions for fibrinolytic enzyme (Nattokinase) production by Bacillus sp. B24 using solid state fermentation
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The present study was aimed to screen the ability of local isolates of Bacillus spp. (56 isolates) for nattokinase production using solid state fermentation, then optimize the nutritional conditions for enzyme production. The isolates were subjected to the primary and secondary screening process to select the Bacillus isolate which give the highest production of enzyme. It was found that Bacillus sp. B24 had the highest productivity of the enzyme (25.58U/mg protein). The optimum conditions for nattokinase production were performed by the solid state fermentation and found that the wheat bran was the best medium at initial moisture ratio 1.0:1.0 (w/v) using distilled water as moisturizing solution with initial pH of 7.0 after inoculation

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Publication Date
Thu Dec 01 2022
Journal Name
Journal Of Engineering
The Optimum Reinforcement Layer Number for Soil under the Ring Footing Subjected to Inclined Load
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The primary components of successful engineering projects are time, cost, and quality. The use of the ring footing ensures the presence of these elements. This investigation aims to find the optimum number of geogrid reinforcement layers under ring footing subjected to inclined loading. For this purpose, experimental models were used. The parameters were studied to find the optimum geogrid layers number, including the optimum geogrid layers spacing and the optimum geogrid layers number. The optimum geogrid layers spacing value is 0.5B. And as the load inclination angle increased, the tilting and the tilting improvement percent for the load inclination angles (5°,10°,15°) are (40%,28%, and 5%) respectively. The reduction percent o

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Publication Date
Tue Sep 08 2020
Journal Name
Baghdad Science Journal
The Suggested Reciprocal Relationship between Maximum, Minimum and Optimum Usable Frequency Parameters Over Iraqi Zone
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In this work, the relationship between the ionospheric parameters (Maximum Usable Frequency (MUF), Lowest Usable Frequency (LUF) and Optimum working Frequency (OWF)) has been studied for the ionosphere layer over the Iraqi zone. The capital Baghdad (44.42oE, 33.32oN) has been selected to represent the transmitter station and many other cities that spread over Iraqi region have represented as receiver stations. The REC533 communication model considered as one of the modern radio broadcasting version of ITU has been used to calculate the LUF parameter, while the MUF and OWF ionospheric parameters have been generated using ASAPS international communication model which represents one of the most advanced  and

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Publication Date
Thu Dec 01 2022
Journal Name
Journal Of Engineering
The Optimum Reinforcement Layer Number for Soil under the Ring Footing Subjected to Inclined Load
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The primary components of successful engineering projects are time, cost, and quality. The use of the ring footing ensures the presence of these elements. This investigation aims to find the optimum number of geogrid reinforcement layers under ring footing subjected to inclined loading. For this purpose, experimental models were used. The parameters were studied to find the optimum geogrid layers number, including the optimum geogrid layers spacing and the optimum geogrid layers number. The optimum geogrid layers spacing value is 0.5B. And as the load inclination angle increased, the tilting and the tilting improvement percent for the load inclination angles (5°,10°,15°) are (40%,28%, and 5%) respectively. The reduction percent of the

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Publication Date
Tue Sep 08 2020
Journal Name
Baghdad Science Journal
The Suggested Reciprocal Relationship between Maximum, Minimum and Optimum Usable Frequency Parameters Over Iraqi Zone
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In this work, the relationship between the ionospheric parameters (Maximum Usable Frequency (MUF), Lowest Usable Frequency (LUF) and Optimum working Frequency (OWF)) has been studied for the ionosphere layer over the Iraqi zone. The capital Baghdad (44.42oE, 33.32oN) has been selected to represent the transmitter station and many other cities that spread over Iraqi region have represented as receiver stations. The REC533 communication model considered as one of the modern radio broadcasting version of ITU has been used to calculate the LUF parameter, while the MUF and OWF ionospheric parameters have been generated using ASAPS international communication model which represents one of the most advanced  and accurate HF sky wave prop

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Publication Date
Wed Apr 01 2020
Journal Name
Civil Engineering Journal
Model Development for the Prediction of the Resilient Modulus of Warm Mix Asphalt
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Increasing material prices coupled with the emission of hazardous gases through the production and construction of Hot Mix Asphalt (HMA) has driven a strong movement toward the adoption of sustainable construction technology. Warm Mix Asphalt (WMA) is considered relatively a new technology, which enables the production and compaction of asphalt concrete mixtures at temperatures 15-40 °C lower than that of traditional hot mix asphalt. The Resilient modulus (Mr) which can be defined as the ratio of axial pulsating stress to the corresponding recoverable strain, is used to evaluate the relative quality of materials as well as to generate input for pavement design or pavement evaluation and analysis. Based on the aforementioned preface, it is

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Publication Date
Thu Jun 30 2022
Journal Name
Iraqi Journal Of Science
Prediction of Deleterious Non-Synonymous Single Nucleotide Polymorphisms (Nssnps) of Human TLR7 Gene
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      Toll-like receptors (TLRs) play a key role in innate immune response activation against viruses. TLR7, one of the TLRs family, is potentially important in controlling viral infection and the production of vaccines against the virus. The wide spectrum of discrepancy in response to antiviral drugs among different populations which is emerged by some pandemics like COVID-19 might be due to their different TLR7 single nucleotide polymorphisms (SNPs). The present study aimed to investigate the consequences of 401 non-synonymous missense SNPs (nsSNPs) within TLR7 on its protein structure, stability, and function by using specific bioinformatics tools. Seven bioinformatics tools were used to investigate 401

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Publication Date
Mon Jan 01 2024
Journal Name
Dental Hypotheses
Evaluation of the Impact of Ozonated Water on Water Sorption and Solubility of Heat Cure Acrylic Resin: An In Vitro Study
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Introduction: This study aimed to evaluate the impact of ozonated water on water sorption and solubility of heat-cure acrylic resin. Methods: Thirty-three samples of heat-cured acrylic resin were manufactured and divided into three groups: control, immersion for 10 and 20 minutes in ozonated water. Water sorption and water solubility tests were carried out in line with ADA Standard No. 12 for denture-base acrylic resin. Data were analyzed using one-way ANOVA at a significance level of 5%. Results: There was a nonsignificant difference between the control and experimental groups regarding water sorption (P

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