Recently, microalgae have become a promising source in the production of biofuel. However, the cost of production is still the main obstacle to develop of this type of source. Although there are many extensive studies on the requirements provided for the cultivation of the microalgae, the study of the process, via the variables that affect the cultivation of microalgae, being still one of the important tasks to improve the production of biofuel. The present article is a serious attempt to investigate of use commercial fertilizer NPK (20:20:20+TE N: P: K) as considered a cheap nutrient medium in growth Chlorella vulgaris by comparison with traditional nutrient (Chu.10 medium). In addition, the current study addresses effect of different sparging periods of filtered air on the microalgae production. The experimental data showed that the use of the NPK fertilizer as cultivation medium in Chlorella vulgaris culture gives more growth rate of microalgae than that produced if the cultivation process was operated with Chu.10 medium. For example the maximum biomass concentration reaches to 0.3249 g L-1 when cultivated in NPK fertilizer, whereas reached to 0.212 g L-1 for cells cultivated in Chu.10 medium. In addition, the results proved that the aeration system in the cultivation can plays an important role in the activity of the microalgae with NPK medium, since it creates a convenient environment with low concentration of oxygen in the medium. The study showed that increasing aeration period for such a type of microalgae increases the growth rate.
The quantum chromodynamics theory approach was taken to study the photonic emission from interaction of quark gluon at high at Bremsstrahlung processes. Strength coupling, quark charge 𝑒𝑞 , flavor number 𝑛𝐹 , thermal energy T of system, fugacity of gluon ƛ𝑔, fugacity of quark ƛ𝑞 , critical temperature 𝑇𝐶 and photons energy 𝐸 are taken to calculate photons rate via the quantum system. Photons emission rate studies and calculates via high energy 400MeV to 650 MeV using flavor number 3 and 7 for 𝑢̅𝑔 → 𝑑̅𝑔𝛾 and 𝑐𝑔 → 𝑠𝑔𝛾 systems at bremsstrahlung processes with critical temperature (𝑇𝑐 = 190 and 196) MeV with photons energy (1-10) GeV. The confinement and de-confineme
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Two series of 1,3,4-oxadiazole derivatives at the sixth position of the 2,4-di-
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The quantum chromodynamics theory approach was taken to study the photonic emission from interaction of quark gluon at high at Bremsstrahlung processes. Strength coupling, quark charge 𝑒𝑞 , flavor number 𝑛𝐹 , thermal energy T of system, fugacity of gluon ƛ𝑔, fugacity of quark ƛ𝑞 , critical temperature 𝑇𝐶 and photons energy 𝐸 are taken to calculate photons rate via the quantum system. Photons emission rate studies and calculates via high energy 400MeV to 650 MeV using flavor number 3 and 7 for 𝑢̅𝑔 → 𝑑̅𝑔𝛾 and 𝑐𝑔 → 𝑠𝑔𝛾 systems at bremsstrahlung processes with critical temperature (𝑇𝑐 = 190 and 196) MeV with photons energy (1-10) GeV. The confinement and de-confineme
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The education sector suffers from many problems, including the scarcity of schools that can absorb the increasing number of students in light of the increasing population growth rate, as some regions suffer from a lack of opening of new schools or the expansion of existing schools to increase their capacity so that attention is required. The research sought to identify the level of maturity of project management at the research site (Building Department in Al-Karkh I/ Ministry of Education) Being responsible for educational projects and their implementation and to know that, the ten areas of the knowledge guide to project management PMBOK have been adopted according to the PM3 model (one of the models of maturity
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The research deal with three variables of exceptional importance to organization business firms. These variables are emotional intelligence, transformational leadership, and organizational performance. The aim of this research is to determine the effect of emotional intelligence and transformational leadership on organizational performance at the banking sector, which is represented by Al-Rafidain Bank. The problem of the research is expressed by many questions related with the nature of the interrelationships and effects among research’s variables. The researcher has depended upon the descriptions - analytical approach. on a random sample of (80 ) managers
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This study aimed to investigate the influence of longitudinal steel embedded tubes located at the center of the column cross-section on the behavior of reinforced concrete (RC) columns. The experimental program consisted of 8 testing pin-ended square sectional columns of 150×150 mm, having a total height of 1400 mm, subjected to eccentric load. The considered variables were the steel square tube sizes of 25, 51 and 68 mm side dimensions and the load eccentricity (50 and 150) mm. RC columns were concealed steel tubes with hollow ratios of 3%, 12% and 20% depending on tube sizes used. The experimental results indicated an improvement in the overall behavior of eccentric columns when steel embedded tubes are used. The maximum gain in
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Vibration analysis plays a vital role in understanding and analyzing the behavior of the structure. Where, it can be utilized from this analysis in the design process of the structures in different engineering applications, check the quality and safety of the structure under different working conditions. This work presents experimental measurements and numerical solutions to an out of plane vibration of a rectangular plate with a circular hole. Free edges rectangular plates with different circular holes diameters were studied. The effects of hole location on the plate natural frequencies were also investigated. A finite element modeling (using ANSYS Software) has been used to analyze the vibration characteristics of the plates. A good agree
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The piled raft is a geotechnical composite construction consisting of three elements: piles, raft and soil.
In the design of piled rafts, the load shared between the piles and the raft, and the piles are used up to a
load level that can be of the same order of magnitude as the bearing capacity of a comparable single
pile or even greater. Therefore, the piled raft foundation allows reduction of settlements in a very
economic way as compared to traditional foundation concepts.
This paper presents experimental study to investigate the behavior of piled raft system in sandy
soil. A small scale “prototype” model was tested in a sand box with load applied to the system through
a compression machine. The settlement was
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A cantilever beam is made from composite material which is consist of (matrix: polyester) and (particles: Silicon-Carbide) with different volume fraction of particles. A force is applied at the free end of beam with different values. The experimental maximum deflection of beam which occurs at the point of the applied load is recorded. The deflection and slope of beam are analyzed by using FEM modeling. MATLAB paltform is built to assemble the equations, vector and matrix of FEM and solving the unknown variables (deflection and slope) at each node. Also ANSYS platform is used to modeling beam in finite element and solve the problem. The numerical methods are used to compare the results with the theoretical and experimental data. A good ag
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