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Free Vibration Analysis of Laminated Composite Plates with General Boundary Elastic Supports Under Initial Thermal Load
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Free vibration behavior was developed under the ratio of critical buckling temperature of laminated composite thin plates with the general elastic boundary condition. The equations of motion were found based on classical laminated plate theory (CLPT) while the solution functions consists of trigonometric function and a continuous function that is added to guarantee the sufficient smoother of the so-named remaining displacement function at the boundaries, in this research, a modified Fourier series were used, a generalized procedure solution was developed using Ritz method combined with the imaginary spring technique. The influences of many design parameters such as angles of layers, aspect ratio, thickness ratio, and ratio of initial in- plane thermal load in addition to different boundary conditions on the natural frequencies of laminated plate is analyzed. In general, the changes of fundamental natural frequency is inversely proportional with the ratio of thermal buckling load, also most parameters aspect ratio effect on the natural frequency about 35 – 40%. The present results were compared with those obtained by other researchers, and show good agreement.

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Publication Date
Mon May 22 2023
Journal Name
Proceedings Of The 1st International Conference On Frontier Of Digital Technology Towards A Sustainable Society
Effect of thermal annealing on the structural and optical properties of Sb2Se3 thin films
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In this paper the effect of thermal annealing on the structural and optical properties of Antimony Selenide (Sb2Se3) is investigated. Sb2Se3 powder is evaporated on clean amorphous glass substrates at room temperature under high vacuum pressure (4.5×10-6 mbar) to form thin films. The structural investigation was done with the aid of X-ray diffraction (XRD) and atomic force microscopy (AFM). The amorphous to polycrystalline transformation of these thin films was shown by X-ray diffraction analysis after thermal annealing. These films' morphology is explained. (UV-Vis ) spectra in ranges from 300 to 1100 nm was used to examine the optical properties of the films .The absorption coefficient and optical energy gap of the investigated films are

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Publication Date
Sun Jun 01 2008
Journal Name
Baghdad Science Journal
Study of Spectral and thermal properties of Selenium Diatomic Halides by Semi-empirical Treatment
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The spectroscopic properties, potential energy curve, dipole moments, total charge density, Electrostatic potential as well as the thermodynamic properties of selenium diatomic halides have been studied using code Mopac.7.21 and hyperchem, semi-empirical molecular orbital of MNDO-method (modified neglected of differential overlap) of parameterization PM3 involving quantum mechanical semi-empirical Hamiltonian. The relevant molecular parameters like interatomic distance, bond angle, dihedral angle and net charge were also calculated.

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Publication Date
Sat Oct 19 2024
Journal Name
Baghdad Science Journal
Synthesis, Characterization and Study of Thermal Properties of New Silicone Polymers and Their Nanocomposites
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الهدف من الدراسه تحضير فئه جديده من بوليمرات السليكون P1-P4  والتي تمت على اساس استحدام ثنائي مثيل ثنائي كلورو سيلان((DCDMS مع بعض المركبات العضويه التي تحتوي مجاميع الهيدروكسيل  الطرفيه والتي حضرت لاول مره M1-M4،  بأستخدم البلمره التكثيفيه .كما تم تحضير متراكباتها النانويهP′1-P′4  بوجود جسيمات الفضه النانويه (Ag-NPs)  باستخدام طريقة صب المحاليل. شخصت جميع التراكيب للمونمرات والبوليمرات المحضره باستخدام  مطيافية

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Publication Date
Tue Mar 31 2015
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Production and Evaluation of Liquid Hydrocarbon Fuel from Thermal Pyrolysis of Virgin Polyethylene Plastics
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   Pyrolysis of virgin polyethylene plastics was studied in order to produce hydrocarbon liquid fuel. The pyrolysis process carried out for low and high-density polyethylene plastics in open system batch reactor in temperature range of 370 to 450°C.

   Thermo-gravimetric analysis of the virgin plastics showed that the degradation ranges were between 326 and 495 °C. The results showed that the optimum temperature range of pyrolysis of polyethylene plastics that gives highest liquid yield (with specific gravity between 0.7844 and 0.7865) was 390 to 410 °C with reaction time of about 35 minutes. Fourier Transform Infrared spectroscopy gave a quite evidence that the produced hydrocarbon liquid fuel consisted ma

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Publication Date
Sun Jul 01 2012
Journal Name
Journal Of Educational And Psychological Researches
Under the title "ideas to demonstrate and prove some new insight into the measurement of psychological and educational assessment"Paragraphs of the psychometric analysis between the logical and virtual (for arbitrators experts and specialists) and the sta
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   Thsst researcher problem of delays faced by researchers are all waiting to evaluate their standards by the experts who must take their views to extract the truth Virtual important step first step in building standards whatsoever, then the difference of opinion among experts about the paragraphs Whatever the scope of their functions, leading to confusion in maintaining these paragraphs or delete? Or ignore the views and opinion of the researcher to maintain the same? Or as agreed upon with the supervisor if he was a student? Especially if the concepts of a modern new building.
   Therefore, the researcher sought to try to find a solution to her problem to conduct an experiment to test building steps

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Publication Date
Sun Dec 06 2015
Journal Name
Baghdad Science Journal
Synthesis and Characterization of Some New Benzodiazepinium Salt Derivatives under microwave Irradiation
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An attempt to synthesize the benzoimidazol derivatives from the reaction of o-phenylenediamine and benzoic acid derivatives in the presence of ethanol and various ketones under microwave irradiation, 1 , 5 - benzodiazepinum salt derivatives were obtained instead of them. Unexpected reaction was happened for synthesis a new series of benzodiazepinium salt derivatives in a selective yield . The reaction mechanism was also discussed. The new compounds were purified and identified their structures were elucidated using various physical techniques like; FT- IR spectra, micro elemental analysis (C.H.N) and 1H NMR spectra.

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Publication Date
Mon Jan 01 2024
Journal Name
Baghdad Science Journal
Estimating the Parameters of Exponential-Rayleigh Distribution under Type-I Censored Data
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     This paper discusses estimating the two scale parameters of Exponential-Rayleigh distribution for singly type one censored data which is one of the most important Rights censored data, using the maximum likelihood estimation method (MLEM) which is one of the most popular and widely used classic methods, based on an iterative procedure such as the Newton-Raphson to find estimated values for these two scale parameters by using real data for COVID-19 was taken from the Iraqi Ministry of Health and Environment, AL-Karkh General Hospital. The duration of the study was in the interval 4/5/2020 until 31/8/2020 equivalent to 120 days, where the number of patients who entered the (study) hospital with sample size is (n=785). The number o

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Publication Date
Thu Feb 27 2020
Journal Name
Iraqi Journal Of Science
Gene Expression of pelA and pslA in Pseudomonas Aeruginosa under Gentamicin Stress
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     Pseudomonas aeruginosa produces an extracellular biofilm matrix that consists of nucleic acids, exopolysaccharides, lipid vesicles, and proteins. Alginate, Psl and Pel are three exopolysaccharides that constitute the main components in biofilm matrix, with many biological functions attributed to them, especially concerning the protection of the bacterial cell from antimicrobial agents and immune responses. A total of 25 gentamicin-resistant P. aeruginosa selected isolates were enrolled in this study. Biofilm development was observed in 96% of the isolates. In addition, the present results clarified the presence of pelA and pslA in all the studied isolates. The expression of these genes was very low. Even though all biof

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Publication Date
Sun Sep 01 2013
Journal Name
Baghdad Science Journal
Induction of antioxidant enzymes in wheat (Triticum spp.) grown under salt stress
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A pot culture experiment was conducted at the greenhouse of soil and water resources department in College of Agriculture, University of Baghdad in Abo-Ghraib at season 2009-2010 to investigate the effects of using foliar application of some macro and micronutrients in induce antioxidant enzymes in wheat grown under salt stress . Doar85 planted under three levels of salt stress, and three combinations of foliar application were used from nutrients (K+ Ca) at 3000 and 1500 mg.L-1 respectively, and (Fe + Zn + Mn) at 30, 20, and 10 mg.L-1 respectively , and ( K+ Ca) + (Fe+ Zn + Mn). The results showed that increasing levels of sodium chloride in the irrigation of water significantly increased at p<0.05 level SOD and POD activity

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Publication Date
Sun Jan 01 2017
Journal Name
Pakistan Journal Of Biotechnology
Role of bio fertilization on wheat and water productivity under water scarcity
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Field experiment was conducted by using two fertilization systems (i.e.) biofertilizers (inoculation with Pseudomonas putida and with Azotobacter chroococcum and non - inoculation) and chemical fertilization (100%, 50% and 25% of recommended by Ministry of Agriculture) to study the influence of these system and interaction on water and grain yield productivity, some growth phytohorones and number of bacterial cells in soil rizosphere of root of wheat crop under water scarcity. The result showed that the integrate fertilization (inoculation with Pseudomonas putida and Azotobacter chroococcum bacterial + 50% of the recommended chemical fertilizer) recorded 5.70 and 5.55 t ha-1, respectively with reducing the chemical fertilizer app

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