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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 Feb 04 2019
Journal Name
Journal Of The College Of Education For Women
The eloquence of the poetic image in the poetry of the Andalusian son of Labanism is a stylistic approach
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The resort to the eloquence of the poetic image as a style reveals the poet's creativity and creativity in dealing with external influences, and reflect them with emotional images express a sense of intense emotional imagination, and this imagination stems from the experience of a poetic sense of truth, tasted by the recipient before the creator of the poetic text.

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Publication Date
Wed Aug 03 2022
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The adequacy of foreign reserves and their role in the stability of the exchange rate of the Iraqi dinar
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Many countries are very important in their interest not only in diversifying foreign reserves, but in determining and planning their volume in accordance with the goals set, namely facing potential external shocks, as the research aims to determine the extent of the strength of foreign reserves in the possession of the Central Bank in relation to every influential variable in the Iraqi economy. , in order to determine the minimum level of reserves that requires reconsideration of the exchange rate, as the research adopted the inductive analytical method in analyzing real (Quantitative data) for the research variables in the years of study, as the research adopted a set of analytical indicators approved by the International Moneta

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Publication Date
Tue Dec 11 2018
Journal Name
Iraqi National Journal Of Nursing Specialties
Impact of Adolescents' Family Meal Eating Patterns upon their Weight Control Behaviors at Secondary Schools in Baghdad City
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Objective: The study aimed to identify the adolescents' family meal eating patterns, and find out the relationship between adolescents' family meal eating patterns and their weight control behaviors. Methodology: A descriptive study was conducted on impact of adolescents' family meal eating patterns upon their weight control behaviors in secondary schools at Baghdad city, starting from 20th of April 2013 to the end of October 2014. Non- probability (purposive) sample of 1254 adolescents were chosen from secondary schools of both sides of Al-Karkh and Al-Russafa sectors. Data was collected through a specially

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Publication Date
Sun Apr 03 2016
Journal Name
Journal Of Educational And Psychological Researches
The Level of Computer Literacy of the Students at Al Quds Open University in Tulkarm Branch
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The purpose of this study is to assess the level of computer literacy of the students at AlQuds open university in Tulkarm Branch. The study investigates the effects of the variables of gender, specialization, academic level, owning a personal computer, internet communication, and own an email account on the level of computer literacy. A test of computer literacy was constructed by the researchers consisting of (37) multiple choice items with a reliability rate (0.85). The study population consisted of (4100) students, while the sample contained (352) students. The study revealed that the level of computer literacy of the students at AlQuds Open University in Tulkarm Branch was (66.2 %) which is educationally acceptable. It also

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Publication Date
Sat Apr 10 2021
Journal Name
المؤتمر العلمي الدولي الثالث - المجلة الامريكية الدولية للعلوم الانسانية والاجتماعية
Public Governance and Sustainable Development - A descriptive study of the reality of public institutions in Iraq
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In light of crises, the need for efficient and flexible public administrations to make quick and decisive decisions, also institutions capable of directing the internal elements and components of them and adapting them to the requirements of rapid change due to crises and disasters, which led to scarce resources becoming scarcer and economic, political and social problems becomes more prominent. For the majority of developing countries, including Iraq, the increasing need for the importance of moving towards enhancing the efficiency of the performance of public institutions while trying to predict their future, can only be achieved. Through solid mechanisms and principles of governance that enhance the ability of institutions and make them

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Publication Date
Fri Sep 30 2022
Journal Name
Journal Of Economics And Administrative Sciences
The impact of digital leadership in the effectiveness of organizational crisis management by mediating strategic vigilance
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The current research aims to verify the impact of digital leadership as an independent variable, in the effectiveness of crisis management as a response  variable through centralizing strategic vigilance in the faculties of the University of Baghdad and its departments, and to investigate the level of interest of its leaders and subordinates in research variables, as well as coming up with recommendations that contribute to strengthening the practices of the three variables. In the university under study, and based on the researcher’s  interest  to diagnose the influence relationship between the variables, because of their importance in the university’s headquarters and its members on the one hand, and its refl

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Publication Date
Mon May 27 2019
Journal Name
Al-khwarizmi Engineering Journal
Investigation the Optimization of Machining Parameters to Surface Roughness in Free Form Surface of Composite Material
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The aim of this research is to investigation the optimization of the machining parameters (spindle speed, feed rate, depth of cut, diameter of cutter and number of flutes of cutter) of surface roughness for free-form surface of composite material (Aluminum 6061 reinforced boron carbide) by using HSS uncoated flat end mill cutters which are rare use of the free-form surface. Side milling (profile) is the method used in this study by CNC vertical milling machine. The purpose of using ANFIS to obtain the better prediction of surface roughness values and decreased of the error prediction value and get optimum machining parameters by using Taguchi method for the best surface roughness at spindle speed 4500 r.p.m, 920mm/rev feed rate, 0.6mm de

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Publication Date
Wed Jun 01 2011
Journal Name
Journal Of Economics And Administrative Sciences
The effect of losing one view of the independent variableAnd its location in simple regression analysis
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The objective of the research , is to shed light on the most important treatment of the problem of missing values of time series data and its influence in simple linear regression. This research deals with the effect of the missing values in independent variable only. This was carried out by proposing missing value from time series data which is complete originally and testing the influence of the missing value on simple regression analysis of data of an experiment related with the effect of the quantity of consumed ration on broilers weight for 15 weeks. The results showed that the missing value had not a significant effect as the estimated model after missing value was consistent and significant statistically. The results also

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Publication Date
Tue Feb 14 2023
Journal Name
Journal Of Educational And Psychological Researches
Logical Intelligence and its Relationship to the Sensitivity of Sensory Processing of Students in Distinguished Schools
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Abstract

The research aims to identify the logical intelligence of distinguished students and to identify the extent of the contribution of the fields of logical intelligence to the sensitivity of students' sensory processing in distinguished schools. The research sample consisted of (400) male and female students selected by the stratified random method with the proportional method. The scale that was prepared according to the theoretical framework and the adopted theory was applied after being subject to the psychometric properties of validity and reliability, Logical thinking (observation, interpretation, mathematical and arithmetic operations) contributed to sensory processing. The results showed that disting

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Publication Date
Wed Apr 01 2020
Journal Name
Journal Of Economics And Administrative Sciences
The effect of credit risk indicators on the profitability of banks in the Arab gulf countries
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The purpose of this study is to investigate the effect of credit risk indicators on the Arab Gulf countries' banks Profitability over the period of 2015 to 2017.  The banking credit risk was calculated using non-performing loans ratio affecting banks profitability indicators like net income and by using fixed effect and random effect model analyses, the study found that increasing in non-performing loans ratio will decrease the net income in gulf banks, the study also found that personal loans represent the largest share of loans granted in gulf banks. Also, the study recommends the importance of developing the capabilities of credit departments in commercial banks in dealing with bad loans, and studying the financial statem

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