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Statistical Design based on Response Surface Methodology to Optimize the Production of a Yellow Pigment by Streptomyces thinghirensis AF7
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Although its wide utilization in microbial cultures, the one factor-at-a-time method, failed to find the true optimum, this is due to the interaction between optimized parameters which is not taken into account. Therefore, in order to find the true optimum conditions, it is necessary to repeat the one factor-at-a-time method in many sequential experimental runs, which is extremely time-consuming and expensive for many variables. This work is an attempt to enhance bioactive yellow pigment production by Streptomyces thinghirensis based on a statistical design. The yellow pigment demonstrated inhibitory effects against Escherichia coli and Staphylococcus aureus and was characterized by UV-vis spectroscopy which showed lambda maximum of 449. The FTIR and GC-MS analysis showed that the colorings in this type of product are due to the presence of chromo peptides. Furthermore, the GC-MS measurement determined the presence of 4 compounds, as it gave 4 different retention times within this yellow pigment, but with different percentages, except for the compound BHT when the retention time was 17.86 minutes. Starch casein broth (SCB) was selected as an optimized medium for yellow pigment production. The optimization process was first started with one factor at time method, revealing that maltose and casein were the best carbon and nitrogen sources. Response surface methodology based on central composite design was conducted to obtain the optimal combinations of maltose and casein concentrations, pH, and inoculum size for maximum production of yellow pigment. The results showed that casein was the most effective parameter with F-value 393.1 and the model exhibited good fitting with a correlation coefficient of 0.946. Moreover, the actual maximum yellow pigment product 0.80 nm which aggregated with a predicted value 0.835 nm at maltose concentration 8 g/L, casein 5 g/L, KNO3 0.01 g/L, pH 6 and inoculum size 5%.

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Publication Date
Sun Jun 01 2014
Journal Name
Baghdad Science Journal
(?m 10.6) Design study for Reserve of laser CO2
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In this paper , the CO2 laser receiver system is designed and studied, with wavelength laser 10.6 ?m in room temperature , and to evaluate the performance and discussion it via the package of optical design (ZEMAX), from its output the Spot Diagram is measured through RMS ,and from the Ray fan plot , the aberrations is found which is the normal error for the best focus named (under corrected ) , the other output was the Geometric Encircled Energy in the spot diagram . and found that the radius of spot diagram at 80% (R80%) from the total energy ,and focal shift .The designed system have high efficiency and low cost .

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Publication Date
Tue Nov 01 2011
Journal Name
International Journal Of Mechanical And Materials Engineering
Simulation and design optimization of magneto rheological control valve
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Magneto-rheological (MR) Valve is one of the devices generally used to control the speed of Hydraulic actuator using MR fluid. The performance of valve depends on the magnetic circuit design. Present study deals with a new design of MR valve. The finite element analysis is carried out on this valve to optimize its design. The design of the magnetic circuit is accomplished by magnetic finite element software such as Finite Element Method Magnetic (FEMM). The Model dimensions of MR valve, material properties and the circuit properties of valve coil are taken into account. The results of analysis are presented in terms of magnetic strength and magnetic flux density. The valve can be operated with variable flow rate by varying the current. It i

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Scopus
Publication Date
Sun Sep 07 2008
Journal Name
Baghdad Science Journal
Design of Immersion Electrostatic LensOperated under Zero Magnification Condition
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The inverse problem is important method in the design of electrostatic lenses which is used in this work, with new technique by suggesting an axial electrostatic potential distribution using polynomial functions of the third order. The paraxial-ray equation is solved to obtain the trajectory of particles that satisfy the suggested potential function.In this work design of immersion electrostatic lens operated under zero magnification condition. The electrode shape of sthe electrostatic lens was the dermined from the solution of laplace equation and plotted in two deimensions . The results showed low values of spherical and chromatic aberrations , which are considered as good criteria for good desigh.

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Publication Date
Mon Jul 10 2023
Journal Name
Journal Of Engineering
Design and Implementation of Single-Phase Boost PFC Converter
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In this paper, a single-phase boost type ac-dc converter with power factor correction (PFC) technique is designed and implemented. A current mode control at a constant switching frequency is used as a control strategy for PFC converter. The PFC converter is a single-stage singleswitch boost converter that uses a current shaping technique to reshape the non-sinusoidal input current drawn by the bulky capacitor in the conventional rectifier. This technique should provide an input current with almost free-harmonics, comply with the IEC61000-3-2 limits, and a system operates with near unity power factor. The other function of the boost converter that should be
accomplished is to provide a regulated DC output voltage. The complete designed

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Publication Date
Mon Feb 04 2019
Journal Name
Journal Of The College Of Education For Women
Computer-Aided-Design of low aberration electrostatic Immersion lens
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A computerized investigation has been carried out to design an immersion lens
with low aberration operating under zero magnification condition using inverse problem.
The aberration is highly dependent on the shape of electrodes, for a preassigned electron
beam trajectory the paraxial-ray-equation is solved to determine the electrostatic potential
and field distribution.
From the knowledge of the potential and its first and second derivative the
electron optical properties were computed, the electrode geometry was determined from
the solution of Laplace equation.

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Publication Date
Mon Mar 25 2019
Journal Name
Al-academy
Effectiveness of Interpretation in Graphic Design: سحر علي سرحان
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The interpretation is one of the means used to by the designer to construct his perceptions of the world in which he lives, either to better understand or rediscover or reproduce the new thing and the creative thing which is characterized by novelty and originality. The design innovations in the political posters, achieved by the designer, result from his perceptions for the response towards a certain subject through what he has of practical experience to interpret his ideas and his desire to achieve harmony with the reality and compatibility with his aims in visible visual effects that will be established in the recipient's memory and stimulate his senses in the realization of the content of the media message. The political poster has a

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Publication Date
Mon Apr 01 2024
Journal Name
Latin American Journal Of Pharmacy
The protective effect of iraqi Juniperus oxycedrus plant on acute kidney injury induced by lipopolysaccharide in mice model
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Inflammatory control is essential to diminish injury and make renal injury treatment simpler. Proposed therapeutics have primarily targeted pro-inflammatory variables. Juniperus oxycedrus was frequently used to treat a variety of infectious disorders, hyperglycemia, obesity, TB, bronchitis, inflammation, and pneumonia. Juniperus oxycedrus twigs and leaves were defatted with n-hexane using Soxhlet apparatus then the residue of plant material dried and re-extracted sequentially by two different solvents Ethylacetate and methanol. The pro-inflammatory markers IL-1 and iNOS, as well as the potential kidney biomarker KIM-1, TNF-α, and transcription factor NF-KB were measured using the RealTime Quantitative qPCR method. The results showed that J

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Publication Date
Mon Jun 01 2020
Journal Name
Iraqi Journal Of Physics
Effect depositions parameters on the characteristics of Ni0.5Co0.5Fe2O4 nanocomposite films prepared by DC reactive magnetron Co-Sputtering technique
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In this work, spinel ferrites (NiCoFe2O4) were prepared as thin films by dc reactive dual-magnetron co-sputtering technique. Effects of some operation parameters, such as inter-electrode distance, and preparation conditions such as mixing ratio of argon and oxygen in the gas mixture, on the structural and spectroscopic characteristics of the prepared samples were studied. For samples prepared at inter-electrode distance of 5 cm, only one functional group of OH- was observed in the FTIR spectra as all bands belonging to the metal-oxygen vibration were observed. Similarly, the XRD results showed that decreasing the pressure of oxygen in the gas mixture lead to grow more crystal planes in the samples prepare

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Publication Date
Wed Jun 30 2021
Journal Name
Journal Of Economics And Administrative Sciences
Management by roaming and self-efficacy and their impact on the excellence of hotel service: An applied study
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      This research investigates the type and the significant relationship between roaming management and self-efficacy and its impact on excellence in providing hotel service. To achieve this, the applied approach was adopted through  A questionnaire was designed and developed for the collected data. It has consisted of three parts. The firsts section included nine questions to measure the dimensions of management by roaming. The second section includes nine questions to measure the effectiveness of the two employees. The last section includes   12   questions to measure the excellence of the hotel service. The research sample included  43  employees' responding to this

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Crossref
Publication Date
Sat Oct 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
Strategic planning of human resources and its impact on the stages of a career path :A field research in the Ministry of Health
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Abstract

The objective of this research is to analyze the relationship between the strategic planning for human resources and career path, and I have tested Search the Ministry of  Health and some health centers headquarters in the Karkh district, that is applied in sample Consist of (45) Deputy Director, Head of Depts, Departmental Manager, and health center Manager.

Find interested in studying the two subjects are important and vital, at the level of organizations at the present time, namely the strategic planning of human resources and career path. To achieve the objectives of the research was designed Qusestionnair (31) items to collect  Primary data. and collected t

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