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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
Mon Jul 01 2019
Journal Name
Journal Of Educational And Psychological Researches
The Level of Academic Achievement and its Relationship with Some Characteristics of Female Students at College of Education for Girls in Baghdad University: The Level of Academic Achievement and its Relationship with Some Characteristics of Female Students at College of Education for Girls in Baghdad University
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Abstract

Personality is one of the most important elements that should be developed in university student. Thus, we have to develop the positive traits and neutralize the negative traits of students as well as we have to pay attention to the level of student achievement at the same time, the researcher designed a scale to measure the traits of study sample. The research come out with a number of recommendations and proposals, the most important of which Enhancing the positive characteristics of university students in order to reach them to the level of mature personality with mental health. Enhancing the positive role of the high level of achievement by motivating the stude

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Publication Date
Mon Jan 01 2024
Journal Name
Journal Of Engineering
Investigate IPD Factors' Effect on Value Engineering for the Communication Sector in Iraq
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Integrated project delivery is collaboratively applying the skills and knowledge of all participants to optimize the project's results, increase owner value, decrease waste, and maximize efficiency during the design, fabrication, and construction processes. This study aims to determine IPD criteria positively impacting value engineering. To do this, the study has considered 9 main criteria according to PMP classification that already covers all project phases and 183 sub-criteria obtained from theoretical study and expert interviews (fieldwork). In this study, the SPSS (V26) program was used to analyze the main criteria and sub-criteria priorities from top to bottom according to their values of the Relative Importance In

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Publication Date
Mon Dec 02 2013
Journal Name
Iraqi Medical Journal
Etiology and Antibiotic Sensitivity for Otitis Media in A Central Pediatric Teaching Hospital.
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Publication Date
Wed Mar 16 2011
Journal Name
Alustath
The Search for Power in C. P. Snow The Light and the Dark
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The Light and the Dark is the fourth novel in a series written by Charles Percy Snow where it tackles a phase of gifted scholar and remarkable individual Roy Calvert as he search for a source of power and meaning in life to relieve his inner turmoil. The character Roy Calvert is based on Snow's friend, Charles Allbery who exposes the message the character of Roy intends to convey in a certain phase of his life and the prophecy the novel carries amid catastrophe so widespread in the thirties of the twentieth century

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Publication Date
Sat Nov 14 2020
Journal Name
Journal Of Information Systems And Telecommunication (jist)
Optical Power Distributions for 4×4 MIMO Visible Light Communications in Indoor Environment
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Visible Light Communication (VLC) has emerged as a powerful technique for wireless communication systems. Providing high data rate and increasing capacity are the major problems in VLC. Recent evidence suggests that Multiple Input Multiple Output (MIMO) technique can offers improved data rates and increased link range. This paper describes the design and implementation of visible light communication system in indoor environment exploring the benefits of MIMO. The specific objective of this research was to implement a 4× 4 Multiple Input (LEDs) Multiple Output (photodetectors)-VLC communication system, where a 16 white power LEDs in four arrays are setting up at transmitter and four RX modules are setting up at receiver side without the nee

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Publication Date
Mon Aug 01 2022
Journal Name
Monatshefte Für Chemie - Chemical Monthly
Al-, Ga-, and In-decorated BP nanotubes as chemical sensors for 2-chloroethanol
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B3LYP density functional is utilized for probing the effect of decorating Al, Ga, and In on the sensing performance of a boron phosphide nanotube (BPNT) in detecting the 2-chloroethanol (CHE) molecule. We predict that the interaction of pure BPNT with CHE is physisorption, and the sensing response (SR) of BPNT is approximately 6.3. The adsorption energy of CHE is about − 26.3 to − 91.1, − 96.6, and − 100.3 kJ/mol, when the Al, Ga, and In metals are decorated on the BPNT surface, respectively. This indicates that the decorated metals significantly strength the interaction. Also, the corresponding SR meaningfully rises to 19.4, 41.0, and 93.4, indicating that by increasing the atomic number of metals, the sensitivity i

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Publication Date
Wed Dec 15 2021
Journal Name
Al-academy
Recycling waste toys to accessories suggested uniform for educational units in kindergarten stages
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This research considers the preservation of environment through recycling old toys. This is achieved by transforming the old toys into educational clothing accessories for kindergarten stages. The research methodology adapts both descriptive and applied approaches. The research questionnaire targeted a sample of 35 teachers to collect information about the waste toys in kindergarten. Also, another sample of 30 teachers and mothers were targeted to measure the suitability of the clothing designs for the early childhood stages. The results shows that both teachers and mothers were well satisfied with clothing accessories designed with the toys waste. This concept contributes to limiting the pollution caused by toys and could save time, eff

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Publication Date
Fri Jun 04 2021
Journal Name
Turkish Journal Of Computer And Mathematics Education (turcomat)
Systems thinking skills included in the mathematics textbook for the third intermediate grade
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Abstract:  The aim of the current research is to find out the extent to which systems thinking skills are included in the mathematics textbook scheduled for the third intermediate grade for the academic year (2020-2021) by answering the main research question: What are the systems thinking skills included in the mathematics textbook for middle third grade?   The analytical descriptive approach was used, and to achieve the goal of the research, a list of the main systemic thinking skills and sub-skills was prepared, and after analyzing the content of the mathematics textbook, the reliability of the analysis was verified through the analysis over time and through others, and it obtained a reliability rate of 98% us

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Publication Date
Fri Nov 29 2019
Journal Name
Iraqi Journal Of Physics
CdSe/CdS core/shell in polyacrylamide polymer matrix for Quantumdots Luminescent solar concentrator
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Luminescent solar concentrator (LSC) are used to enhance       photoresponsivity of solar cell. The Quantumdots luminescent solar concentrator (QDLSC) consists of CdSe/CdS core/shell nanoparticles embedded in polyacrylamide polymer matrix positioned on the top surface of the silicon solar cell. This procedure improves the conversion efficiency of the bare silicon solar cell. The conversion efficiency of the solar cell has increased from 7.3% to 10.3%.  this improvement is referred to the widening of the response spectral region window  of the a- Si. Solar cell.

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Publication Date
Tue Dec 01 2020
Journal Name
Eurasian Journal Of Biosciences
Utilizing remote sensing for studying Al-Saadya Marsh in the period 1987-2017
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The marshes are one of the important environmental features affecting human and animal systems, so the studying of changes they undergo is one of the important topics. This study is concerned with the changes occurring in the Al Saadya marsh for the period from 1987 to 2017 exclusively in the winter season (the marshes’ revival season in Iraq revive). In order to inspect the changes in this marsh, we choose 7 years to cover the study period as a criterion years, namely 1987, 1990, 1995, 2000, 2007, 2014 and 2017. The “Maximum Likelihood” classifier was used to separate the stacked land cover features, where the minimum overall accuracy ratio that recorded for all years of study was 96%. The results revealed that Al-Saadya marsh went t

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