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Cultivation of Microalgae Chlorella vulgaris in Airlift photobioreactor for Biomass Production using commercial NPK Nutrients
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Airlift reactors are widely used in the chemical and biochemical applications as effective contactors for mass and heat transfer. The main advantages of airlift contactor compared with simple bubble column are ease of construction, low shear rate, high capacity, good mixing and liquid circulation without mechanical agitators and circulating pumps.

In this work, growth characteristics of Chlorella vulgaris microalgae were studied in an internal loop airlift photobioreactor for biomass production. The bioreactor operated under batch and semi-continuous culture mode using commercially available 20:20:20+TE NPK fertilizer as nutrients. The experiments were conducted to evaluate the growth rate and biomass productivity of Chlorella vulgaris microalgae as affected by several factors such as nutrients concentration (20-80 mg/L), inlet air flow rate (2-8 LPM), and harvesting ratio (10-30 vol.%). The growth rate and biomass productivity of Chlorella vulgaris was determined as changes in optical density using UV-spectrophotometer. The results of batch operation showed that the growth rate of Chlorella vulgaris microalgae was increase with increasing of NPK nutrient concentration used but the access to the stationary phase of growth was delayed. The rate of growth was also increase with the increase in air flowrate to a limit then decrease. On the other hand the airlift photobioreactor can be operated in semi- continuous mode successfully by choosing the optimum conditions from the batch step which was 40 mg/L NPK nutrients concentration and 6 LPM and air flowrate. Several ratios of reactor content were harvested and the maximum biomass productivity was 0.142 g/L.day when harvested 10 vol.% every two days.

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Publication Date
Thu Jul 07 2011
Journal Name
Arabian Journal Of Geosciences
Mineralogy, geochemistry, and reserve estimation of the Euphrates limestone for Portland cement industry at Al-Najaf area, South Iraq
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Publication Date
Thu Sep 30 2021
Journal Name
Iraqi Journal Of Science
Analysis of Methods and Techniques Used for Speaker Identification, Recognition, and Verification: A Study on Quarter-Century Research Outcomes
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The theories and applications of speaker identification, recognition, and verification are among the well-established fields. Many publications and advances in the relevant products are still emerging. In this paper, research-related publications of the past 25 years (from 1996 to 2020) were studied and analysed. Our main focus was on speaker identification, speaker recognition, and speaker verification. The study was carried out using the Science Direct databases. Several references, such as review articles, research articles, encyclopaedia, book chapters, conference abstracts, and others, were categorized and investigated. Summary of these kinds of literature is presented in this paper, together with statistical analyses

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Publication Date
Mon Dec 24 2018
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
FAUNISTIC REVIEW OF THE GENUS CHAITOPHORUS KOCH, 1854 (APHIDIDAE, CHAITOPHORINAE, CHAITOPHORINI) WITH NEW RECORD SPECIES FOR IRAQ APHID FAUNA
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    A faunistic review of the genus Chaitophorus Koch, 1854, including four species in Iraq is given; the distribution data of each species and their hosts have been recorded. In this investigation the poplar leaf aphid Ch. populialbae (Boyer de Fonscolombe, 1841) is recorded here for the first time in Iraq on popular trees Populus euphratica Oliv. during the period from November 2016 to April 2017 in Baghdad province.

 

    A brief description for apterous viviparous female of this species is given; and a  key to the species of the genus Chaitophorus is constricted.

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Publication Date
Thu Jan 27 2022
Journal Name
Nanomaterials
Improving the Melting Duration of a PV/PCM System Integrated with Different Metal Foam Configurations for Thermal Energy Management
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The melting duration in the photovoltaic/phase-change material (PV/PCM) system is a crucial parameter for thermal energy management such that its improvement can realize better energy management in respect to thermal storage capabilities, thermal conditions, and the lifespan of PV modules. An innovative and efficient technique for improving the melting duration is the inclusion of an exterior metal foam layer in the PV/PCM system. For detailed investigations of utilizing different metal foam configurations in terms of their convective heat transfer coefficients, the present paper proposes a newly developed mathematical model for the PV/PCM–metal foam assembly that can readily be implemented with a wide range of operating condition

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Publication Date
Mon Oct 01 2018
Journal Name
Iraqi Journal Of Physics
Study of matter density distributions, elastic charge form factors and size radii for halo 11Be, 19C and 11Li nuclei
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In this work, the calculation of matter density distributions, elastic charge form factors and size radii for halo 11Be, 19C and 11Li nuclei are calculated. Each nuclide under study are divided into two parts; one for core part and the second for halo part. The core part are studied using harmonic-oscillator radial wave functions, while the halo part are studied using the radial wave functions of Woods-Saxon potential. A very good agreement are obtained with experimental data for matter density distributions and available size radii. Besides, the quadrupole moment for 11Li are generated.

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Publication Date
Wed Oct 20 2021
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Some Topological and Polynomial Indices (Hosoya and Schultz) for the Intersection Graph of the Subgroup of〖 Z〗_(r^n )
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         Let  be any group with identity element (e) . A subgroup intersection graph of  a subset  is the Graph with V ( ) =  - e and two separate peaks c and d contiguous for c and d if and only if      , Where  is a Periodic subset of resulting from  . We find some topological indicators in this paper and Multi-border (Hosoya and Schultz) of   , where    ,  is aprime number.

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Publication Date
Wed Mar 29 2023
Journal Name
Journal Of The College Of Education For Women
The Omani Sultanate of Zanzibar between Unity and Separation for the Period between (1223-1275 AH/ 1806-1861 A)
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Sultan Said bin Sultan bin Ahmed bin Said Al-Busaidi (1223-1273 AH / 1806-1856 AD) was able to rule Oman and Zanzibar in a unified Arab-African state during his reign. However, it was separated for several reasons. Thus, the study aims to clarify the efforts made by Sultan Said for annexing Zanzibar to Oman, establishing the Arab-African Sultanate, and shedding light on the role played by Britain in dividing the Arab-African Sultanate and separating Zanzibar from the Omani rule in (1275 AH-1861 AD). The study has adopted the historical descriptive analytical approach. The study has reached several conclusions, such as: The economic motivators  were the most important factors that pushed Sultan Said to move his capital from Muscat to

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Publication Date
Fri Nov 15 2024
Journal Name
Iraqi Journal Of Science
Comparative Analysis for the Seasonal Variations of the IF2 and T Ionospheric Indices during Solar Cycles 23 and 24
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In this work, a comparative analysis for the behavior and pattern of the variations of the IF2 and T Ionospheric indices was conducted for the minimum and maximum years of solar cycles 23 and 24. Also, the correlative relationship between the two ionospheric indices was examined for the seasonal periods spanning from August 1996 to November 2008 for solar cycle 23 and from December 2008 to November 2019 for solar cycle 24. Statistical calculations were performed to compare predicted values with observed values for the selected indices during the tested timeframes. The study's findings revealed that the behavior of the examined indices exhibited almost similar variations throughout the studied timeframe. The seasonal variations were

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Publication Date
Mon Apr 03 2023
Journal Name
Journal Of Educational And Psychological Researches
The Effectiveness of a Training Program Based on Connectivism Theory in Developing E-Learning Competencies among Teachers of Islamic Education in Dhofar Governorate
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Abstract

The study aims to build a training program based on the Connectivism Theory to develop e-learning competencies for Islamic education teachers in the Governorate of Dhofar, as well as to identify its effectiveness. The study sample consisted of (30) Islamic education teachers to implement the training program, they were randomly selected. The study used the descriptive approach to determine the electronic competencies and build the training program, and the quasi-experimental approach to determine the effectiveness of the program. The study tools were the cognitive achievement test and the observation card, which were applied before and after. The study found that the effectiveness of the training program

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Publication Date
Thu Jan 16 2025
Journal Name
Al–bahith Al–a'alami
TOPICS OF PEACEFUL COEXISTENCE IN FOREIGN SATELLITE CHANNELS DIRECTED IN THE ARABIC LANGUAGE: (A Research Drawn from Master Thesis)
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This research deals with issues of peaceful coexistence in foreign satellite channels directed in the Arabic language, trying to get acquainted with the most prominent of these topics dealt with the programs subject to analysis and the method of dealing with them and the most used journalistic arts in that.

The research adopted the descriptive approach and the method of content analysis for the purpose of studying the research community represented by the program «Shabab Talk» “Youth Talk” in the German channel Deutsche Welle (DW) and the program «Beina Sam wa Amar» “between Sam and Ammar” in the American free channel, by designing the content analysis form to subject

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