@article { author = {}, title = {دراسة تأثير الفيض الحراري في الاهتزاز الناتج عن جريان مائع خلال أنبوب يحتوي على حاجز في منتصفه}, journal = {Engineering and Technology Journal}, volume = {26}, number = {10}, pages = {401-416}, year = {2008}, publisher = {University of Technology-Iraq}, issn = {1681-6900}, eissn = {2412-0758}, doi = {10.30684/etj.26.10.15}, abstract = {In this work theoretical study is carried out to the effect of heat flux on inducedvibrations from a fluid flow in a simply and flexible supported pipe with arestriction.The water flow in the pipe is assumed to be fully developed region . Thedynamics of a pipe conveying fluid is described by the transfer matrix approach. Itprovides a numerical technique for solving the equations of motion of forced and freevibrations for simply and flexible support .The pipe is divided into (21) nodes and (20)element along its length.Then, from the pipe analysis equation, a fortran Languagecomputer program has been built to embrace the theoretical and analytical work. Andthen to ensure that the program developing is suitable, it has been compared withanother program called (ANSYS Ver.9) which it use FEM.The Obtained results showthat the transfer matrix method is a suitable technique to compute the eigen modes inaddition to the natural frequency of vibration systems.From this research it has beenfound that the heat flux affects the natural frequencies and the amplitude of vibration .So the increasing the thermal force results in the decreasing of the magnitude of thenatural frequencies. The amplitudes of vibration along the pipe increase as the excitationfrequency is so close to the natural frequencies of the system, and this effect ispredominate than the effect of the heat flux .}, keywords = {Effect of Heat Flux On Induced Vibrations,Fluid Flow In A pipe With A Restriction At Mid The Pipe}, url = {https://etj.uotechnology.edu.iq/article_26860.html}, eprint = {https://etj.uotechnology.edu.iq/article_26860_4a3885e2d72381c482151fcea79d4c00.pdf} } @article { author = {}, title = {Computer aided design of runner & gate in die casting}, journal = {Engineering and Technology Journal}, volume = {26}, number = {10}, pages = {417-430}, year = {2008}, publisher = {University of Technology-Iraq}, issn = {1681-6900}, eissn = {2412-0758}, doi = {10.30684/etj.26.10.14}, abstract = {Die Casting is a high tolerance process due to the high Accuracy of Data to reduce theerror factor as much as possible the objective of this paper is to design an AluminumA380 thermo-fan, Aluminum is a low Density ,High Thermal Conductivity & the lowHeat in solidification makes the runner design more difficult, computer Solution inVisual Basic is needed to make a Model of the necessary Equations to CalculateLength ,Depth of Runner , Gate's width & Solidification time Porosity , ComputerGraphic is also Aided by drawing the die & making 3D Solid Model Done withAutoCAD so that later will be linked to the program , Creation of DXF Files wasperformed}, keywords = {}, url = {https://etj.uotechnology.edu.iq/article_26861.html}, eprint = {https://etj.uotechnology.edu.iq/article_26861_122cb2f0651da4cf3f61de98f8b36e34.pdf} } @article { author = {abdul-Majid Nima, Zeid and Sakhi Jabier, Majid and Ismaeel Wagi, Raghidah and Abd Al-Kareem Hussain, Huda}, title = {Extraction, Identification and Antibacterial activity of Cyperus oil from Iraqi C. rotundus}, journal = {Engineering and Technology Journal}, volume = {26}, number = {10}, pages = {1156-1163}, year = {2008}, publisher = {University of Technology-Iraq}, issn = {1681-6900}, eissn = {2412-0758}, doi = {10.30684/etj.26.10.1}, abstract = {Cyperus rotundus has many different uses and these were based on the differentparts of plant. The medical uses of cyperus have been used in medicine forthousands of years. The parts of the cyperus used are its leaves, seeds and oil. TheExtraction process was carried out by steam distillation. Optimum organicextractant determined. The collected oil was identified via Thin LayerChromatography (TLC) using a mixture of Ethylacetate: toluene (1:9) aschromatographic eluent . This study was designed to extract and identify ofessential cyperus oil from C. rotundus .The Antibacterial activity of Cyperus oilwas studied for various microorganisms (Staphylococcus aureus , Klebsiellapneumoniae, Proteus vulgaris, Streptococcus pyogenes , Eschirichia coli andPseudomonas aeruginosa ) using inhibition zone method (Aromatogram). TheMIC and MBC for each microbe were estimated. The oil of C. rotundus was showna remarkable activity against gram-positive bacteria, less antibacterial activity wasfound against gram–negative bacteria and no activity was observed with the oilagainst Pseudomonas aeruginosa and Proteus vulgaris. Novel method forextraction and identification of chemical composition for Iraqi cyperus oil wasconducted. The study of the biological activities of this oil is very importantbecause of needing to be determined whether there is any correlation between thebiological activities and one or more of the chemical compounds purified from C.rotundus oil.}, keywords = {cyperus oil,antibacterial activity,Thin layer chromatography}, url = {https://etj.uotechnology.edu.iq/article_26847.html}, eprint = {https://etj.uotechnology.edu.iq/article_26847_0b72651bdcdd970342a5f4b5d0ef8590.pdf} } @article { author = {Z. Yahiya, Khalid}, title = {High-Speed Response Si PIN Photodetector Fabricated and Studied for Visible and Near Infrared Spectral Detection}, journal = {Engineering and Technology Journal}, volume = {26}, number = {10}, pages = {1164-1170}, year = {2008}, publisher = {University of Technology-Iraq}, issn = {1681-6900}, eissn = {2412-0758}, doi = {10.30684/etj.26.10.2}, abstract = {In the present work , PIN photodetector has been fabricated by vacuum evaporationtechnique, Al was evaporated on top side of an intrinsic – type silicon and In was evaporatedon down side and doped for each sides of an intrinsic silicon with thermal diffusion techniqueusing a furnace system, in this method PIN photodetector is made.The optoelectronic and electrical properties of photodetector were studied ,PIN hasspectral responsivity in visible and near infrared region and has peak responsivity atwavelength 900nm ,I-V characteristic under dark condition the ideality factor is 3.2 and builtin-potential was determined by extrapolation of the curve (1/C3) to a point 1/C3=0 equal 0.8v.a high speed response for the photodetector was determined , it is equal less than 2.35nS.}, keywords = {Photodetector,Vacuum evaporation,Thermal diffusion}, url = {https://etj.uotechnology.edu.iq/article_26848.html}, eprint = {https://etj.uotechnology.edu.iq/article_26848_2bcd68c4a0239948a88ab1614a39219c.pdf} } @article { author = {Y. Fattah, Mohammed and F. Aswad, Mohammed and M. Mahmood, Mohammed}, title = {Evaluation Of The Method Of Stress Characteristics For Estimation Of The Soil Bearing Capacity}, journal = {Engineering and Technology Journal}, volume = {26}, number = {10}, pages = {1171-1184}, year = {2008}, publisher = {University of Technology-Iraq}, issn = {1681-6900}, eissn = {2412-0758}, doi = {10.30684/etj.26.10.3}, abstract = {The classical bearing capacity theories rely on the superposition of three separatebearing capacities – a technique that is inherently conservative – but they also rely ontabulated or curve-fitted values of the bearing capacity factor, Nγ, which may beunconservative. Further approximations are introduced if the footing is circular(multiplicative shape factors are used to modify the plane strain values of , Nc, Nq and Nγ) orif the soil is non-homogeneous (calculations must then be based on some representativestrength). By contrast, the method of stress characteristics constructs a numerical solutionfrom first principles, without resorting to superposition, shape factors or any other form ofapproximation.In this paper, the validation of the method of stress characteristics is tested by solvinga wide range of bearing capacity problems. The results are compared with classical bearingcapacity theories; namely, Terzaghi, Myerhof, Hansen and Vesic methods.It was concluded that the bearing capacity predicted by the method of stresscharacteristics for the case of a circular footing in clay ranges between (3.7 – 4.0) greater thanTerzaghi, Meyerhof, and Vesic methods. This means that the method is not conservative forthis case and can be dependent for economic design of foundations. The bearing capacitypredicted by this method increases linearly with (D/B).For all values of the angle of friction, φ, the method reveals bearing capacity values forsmooth footings greater than Terzaghi and Hansen and smaller than Meyerhof and Vesictheories. Considering the foundation to be rough, the method gives bearing capacity valuesgreater than all other methods. The difference increases as the angle of internal friction(φ) increases. This makes the method unreliable for rough foundations.}, keywords = {bearing capacity,Stress characteristics}, url = {https://etj.uotechnology.edu.iq/article_26849.html}, eprint = {https://etj.uotechnology.edu.iq/article_26849_d78dc1e98761c4e0a7dcc5db14b172f8.pdf} } @article { author = {Hikmat Bakir, Husam and Hassan Rahil, Falah and Yousif Fattah, Mohammed and Abullateef Al-Neami, Mohammed}, title = {Effect Of Soil Consistency On Flow Characteristics Of Acids Through Cohesive Soils}, journal = {Engineering and Technology Journal}, volume = {26}, number = {10}, pages = {1185-1200}, year = {2008}, publisher = {University of Technology-Iraq}, issn = {1681-6900}, eissn = {2412-0758}, doi = {10.30684/etj.26.10.4}, abstract = {The consistency of cohesive soil depends to a large extent on the structure of soil particleswhich may be arranged in two systems; dispersed or flocculated. The presence of salts oracids between the soil particles will alter the arrangement of particles through affecting theattractive and repulsive forces.In this paper, a program of laboratory tests is carried out at the University ofTechnology/ Baghdad on cohesive soils of different values of Atterberg limits. Samples ofthese soils were tested for grain size distribution (sieve analysis and hydrometer). Thefalling head permeability test was carried out to determine the coefficient of permeability ofthe soils to HCl acid.The soil parameters determined in the laboratory will be used in the numericalanalysis.The aim of this study is to apply the finite element method to study the steady flowof pollutants (acids) in a confined aquifer. The program (MULAT) is used for this purpose.The path of flow of the acid through the soil is traced.The basic problem solved in this paper is a one of linear flow in a single confinedaquifer. It represents the case of leakage of acids from storage tank and flow of the acidsthrough the foundation soil. It was concluded from the finite element results that themaximum head caused by the flow of the acid through the soil decreases with the increase ofthe coefficient of permeability and the plasticity index of the polluted soil.}, keywords = {Pollution,Cohesive soil,Acid,Finite elements}, url = {https://etj.uotechnology.edu.iq/article_26850.html}, eprint = {https://etj.uotechnology.edu.iq/article_26850_2078929ab20a6adf7876f5ef3b1fe175.pdf} } @article { author = {Z. Yahia, Khalid}, title = {Study Optoelectronic Properties of Ag2O Heterojunction Prepered by Thermal Oxidation Technique}, journal = {Engineering and Technology Journal}, volume = {26}, number = {10}, pages = {1201-1209}, year = {2008}, publisher = {University of Technology-Iraq}, issn = {1681-6900}, eissn = {2412-0758}, doi = {10.30684/etj.26.10.5}, abstract = {Highly (101)-oriented p-Ag2O thin film with high electrical resistivily was grown bythermal oxidation (TO) on clean monocrystalline p-type Si without any post- depositionannealing. From optical transmittance and absorptance data, the direct optical band gapwas found to be 1.4eV. The electrical and photovoltaic properties of Ag2O/Si isotopeheterojunction were examined in the absence of any buffer layer. Ideality factor ofheterojunction was found to be 3.9. Photoresponse result revealed that there are two peakslocated at. 750 nm and 900nm .}, keywords = {Heterojunction,Thermal oxidation,photovoltaic}, url = {https://etj.uotechnology.edu.iq/article_26851.html}, eprint = {https://etj.uotechnology.edu.iq/article_26851_5ed081ecc6ab4ec6a67433e4e09c9e37.pdf} } @article { author = {Z. Khelifa, Muhannad and Moasa Al-Shukri, Hayder}, title = {Fatigue Study Of E-Glass Fiber Reinforced Polyester Composite Under Fully Reversed Loading And Spectrum Loading}, journal = {Engineering and Technology Journal}, volume = {26}, number = {10}, pages = {1210-1224}, year = {2008}, publisher = {University of Technology-Iraq}, issn = {1681-6900}, eissn = {2412-0758}, doi = {10.30684/etj.26.10.6}, abstract = {Study of the fatigue behaviors experimentally and theoretically of a compositematerial manufactured for this paper by stacking four layers of E-glass fiber indifferent angle orientations (0o, ± 45o, 0o/90o) immersed in polyester resin with totalthickness 4 mm. They were tested under two types of dynamic loads in fully reversibletension-compression load at (R=-1) and spectrum load as fatigue testing, to estimate lifecurves and microscopic an examination was carried out for stress affected and fractureareas. Finite Element Analysis (FEA) using ANSYS Workbench™ was used toevaluate the composite behaviour under fatigue conditions. The results of the fatiguetest show that the uniaxial [04] composite has the highest strength and the fatiguedegradation is also the highest. The high magnification optical microscopy methodshows that the failure of laminas at ± 45oand 0o/ 90o is due to matrix failure in thedirection of the fiber, whereas for the unidirectional lamina at 0o, the failure is due tofiber breakages.}, keywords = {Glass fiber,Composite material fatigue,Spectrum Loading,Fully reversed Loading,Compression}, url = {https://etj.uotechnology.edu.iq/article_26852.html}, eprint = {https://etj.uotechnology.edu.iq/article_26852_00e5fb90021500f291cf1163e01e3386.pdf} } @article { author = {J.Haider, Adawiya and J.Jawad, Hind and N.Saleh, Saleh}, title = {Simulation of the Acousto-optic Interaction in an Optical Bistable Device}, journal = {Engineering and Technology Journal}, volume = {26}, number = {10}, pages = {1225-1234}, year = {2008}, publisher = {University of Technology-Iraq}, issn = {1681-6900}, eissn = {2412-0758}, doi = {10.30684/etj.26.10.7}, abstract = {In this paper, a computer-aided simulation of the relation between peak phase delay and laserintensity ,at different values of the Klein-Cook parameter of the fourth order diffraction, waspresented. The numerical results describing the sound-light interaction in LiNbO3 crystal withand without feedback were presented and discussed. Also, the relations between laserintensities and the acousto-optic frequency and the values of Klein-Cook parameter werestudied. The results were applied to an optical bistable device using MATLAB software.}, keywords = {Sound,light interaction,Acousto,optic,peak phase delay,Bistable Optical Device}, url = {https://etj.uotechnology.edu.iq/article_26853.html}, eprint = {https://etj.uotechnology.edu.iq/article_26853_b53615c184ad1765bdb62d25f4c24e57.pdf} } @article { author = {R. Areef, Sheelan}, title = {THE STUDY OF SOLUTION ABSORPTION AND DIFFUSION COEFFICIENT IN EPOXY COMPOSITE REINFORCED WITH GLASS FIBERS}, journal = {Engineering and Technology Journal}, volume = {26}, number = {10}, pages = {1235-1240}, year = {2008}, publisher = {University of Technology-Iraq}, issn = {1681-6900}, eissn = {2412-0758}, doi = {10.30684/etj.26.10.8}, abstract = {Diffusivity behavior and diffusion coefficient was investigated in this paper for epoxy compositereinforced with glass fibers (woven roven and random direction) together as a sandwich with volumefraction (44). The samples were immersed in different solution for equal time at constant temperature(room temperature ±18oC). The result show that the relative mass gain increased with increasing theimmersion time till they tend saturation moisture mass (M∞) after that the relative mass gain decreased.The result show that the samples immersed in (kerosene) solution had higher mass gain while thesamples immersed in distill water had lower mass gain and the samples immersed in other solution(Benzene, HNO3, KOH, H2O as received) had relatively mass gain between them.Also the results show that the samples immersed in benzene has maximum diffusion coefficient(30.219mm2/day) which means minimum absorption resistance while the samples immersed in (H2O asreceived) has minimum diffusion coefficient (0.191mm2/day) (maximum absorption resistance).}, keywords = {}, url = {https://etj.uotechnology.edu.iq/article_26854.html}, eprint = {https://etj.uotechnology.edu.iq/article_26854_211dbe6ae4b11352f926e3bc971cf729.pdf} } @article { author = {K. Ali, Jawad}, title = {A New Compact Size Microstrip Patch Antenna with Irregular Slots for Handheld GPS Application}, journal = {Engineering and Technology Journal}, volume = {26}, number = {10}, pages = {1241-1246}, year = {2008}, publisher = {University of Technology-Iraq}, issn = {1681-6900}, eissn = {2412-0758}, doi = {10.30684/etj.26.10.9}, abstract = {A new reduced size single probe fed microstrip patch antenna with irregular slitshas been presented to be used as a receiving antenna for Global Positioning Systems(GPS) integrated with cellular handheld mobile wireless systems. The proposed design isbased on the nearly square microstrip patch antenna with two pairs of orthogonal slitscut from the edge. It has been found that this antenna offers further reduction in sizewith good radiation properties required for GPS system. The resulting circularpolarization bandwidth (with axial ratio ≤ 3 dB) has been found to meet that required forthis application. The proposed antenna possesses an average gain of 4.5 dB overall theGPS L1 operation.}, keywords = {GPS Microstrip Antenna,Antenna Miniaturization,Circular Polarization,axial ratio}, url = {https://etj.uotechnology.edu.iq/article_26855.html}, eprint = {https://etj.uotechnology.edu.iq/article_26855_d711c83af50030345349d5c3d4148573.pdf} } @article { author = {Al-Khashab, Mohammad and Al-Hayalee, Mohammed}, title = {Stabilization of Expansive Clayey Soil Modified by Lime with an Emulsified Asphalt Addition}, journal = {Engineering and Technology Journal}, volume = {26}, number = {10}, pages = {1247-1262}, year = {2008}, publisher = {University of Technology-Iraq}, issn = {1681-6900}, eissn = {2412-0758}, doi = {10.30684/etj.26.10.10}, abstract = {This study deals with the possibility of the stabilization of expansive clayey soilpre-treated by lime, with an emulsified asphalt addition.Soil from the "2nd Kafaat" District in Mosul was chosen it is classified as medium tohigh expansiveness in naturally.The pre-treated soil was performed with (0.5, 1.0, and 1.5%) lime addition byweight. After short period, emulsified asphalt was added with different percentagesnamely (2, 4, 6 and 8) by weight, for optimum percentages of an emulsified asphalt togive the most useful stabilization aspects.The test result of lime addition alone showed that there was a considerable reduction insoil plasticity, 1.5% of lime addition converted the clayey soil towards non-plastic types.The emulsified asphalt addition to the mixture, caused slight increase in the plasticitybut, their values in the whole, remained below the value of the natural soil.The specific gravity decreased with the emulsified asphalt addition as well as, a generalreduction, compatible with the increase in the optimum moisture contents.The absorption values of the treated soil with the emulsified asphalt showed consequentreduction as compared with the original one.A significant reduction in swelling pressure and swelling percent were obtained as wellas an improvement in some values of the unconfined compressive strength were realizedat low percentages of emulsified asphalt addition, compatible with reduction in values ofthe high percent additions}, keywords = {}, url = {https://etj.uotechnology.edu.iq/article_26856.html}, eprint = {https://etj.uotechnology.edu.iq/article_26856_9aa575e9c8eeff98329444131c05d51a.pdf} } @article { author = {N. A, Samira and Alhelaly, Amel and J. Saleh, Najat and Alsalhy, Qusay}, title = {Effect of Alcohol as Additives on the Morphology and Separation Performance of Polyethersulfone (PES) Hollow Fiber Ultrafiltration Membranes}, journal = {Engineering and Technology Journal}, volume = {26}, number = {10}, pages = {1263-1273}, year = {2008}, publisher = {University of Technology-Iraq}, issn = {1681-6900}, eissn = {2412-0758}, doi = {10.30684/etj.26.10.11}, abstract = {Hollow fiber ultrafiltration (UF) membranes were prepared usingPolyethersulfone (PES), alcohol (n-Propanol) as additive and N, N-dimethylacetamide(DMAc) as a solvent. Asymmetric hollow fiber UF membranes were spun by wet phaseinversion method from 17 wt% solids of PES/additive/NMP solutions. The alcoholadditive was n-Propanol while the external coagulant was water. Effects of n-Propanolconcentrations in the dope solution on morphology and separation performance of PEShollow fiber UF membranes were investigated. UF membranes were characterized interms of scanning electron microscope (SEM) while UF experiments were conductedusing polyethylene glycol (PEG20,000MW) and poly (vinyl pyrrolidone) (PVP40,000MW), as a solute. It was found that the PES UF membrane morphology changedfrom long two finger-like structure through a short two finger-like structure to the twovoid-like structure as n-propanol concentration in the dope solution increased from 5 to20 wt % using water as a bore fluid; pure water permeation fluxes (PWP) increased from47 to 201 L/m2.h.bar while rejections of PEG MW20,000 and PVP MW40,000 for wetspunPES hollow fiber membranes were decreased with the increasing of n-propanolconcentration up to 20%. Using above method, PES hollow fiber UF membrane withhigh pure water permeation flux could be prepared while the molecular weight cut-off ofPES hollow fiber membranes is approximately 20,000.}, keywords = {Ultrafiltration membrane,hollow fiber,phase inversion method,polyethersulfone,alcohol additive}, url = {https://etj.uotechnology.edu.iq/article_26857.html}, eprint = {https://etj.uotechnology.edu.iq/article_26857_1a57a70bf6e1165900728ab0dcfcac58.pdf} } @article { author = {M. Ismail, Muayed}, title = {Mathematical Correlations Between The Effective Diameter Of Soil And Other Properties}, journal = {Engineering and Technology Journal}, volume = {26}, number = {10}, pages = {1274-1281}, year = {2008}, publisher = {University of Technology-Iraq}, issn = {1681-6900}, eissn = {2412-0758}, doi = {10.30684/etj.26.10.12}, abstract = {The equivalent or the “effective” diameter or size is a well-known parameter in soilclassification and permeability determination. Hazen (1892) on the basis of his study offilter sands found that the diameter that which 10% by weight of soil grains are finer maycause same effects as the given soil. Denoted as D10, Hazen called this diameter the“effective diameter”.The goal of this study is to determine the value of the percent finer that correspondsto the equivalent diameter of soil grains that may be used directly to calculate as accurate aspossible the surface area of the soil solids. The equivalent or the effective diameter wouldcertainly vary according to the gradation of the soil grains, the wider the range of particlediameters included in the soil matrix the smaller would be the effective diameter.It was concluded that the effective particle diameter of a soil can be related to othersoil properties such as the liquid limit, plasticity index, the unconfined compressive strengthand the standard penetration test number of blows (N).}, keywords = {}, url = {https://etj.uotechnology.edu.iq/article_26858.html}, eprint = {https://etj.uotechnology.edu.iq/article_26858_c33aa4df068f3de3f1c90f8ded71b6ce.pdf} } @article { author = {Abbas Abdulmajeed, Basma and Sabri, Ali}, title = {Theoretical and Numerical Analysis of Fuel Droplet Combustion Parameters via Different Combustion Models}, journal = {Engineering and Technology Journal}, volume = {26}, number = {10}, pages = {1282-1300}, year = {2008}, publisher = {University of Technology-Iraq}, issn = {1681-6900}, eissn = {2412-0758}, doi = {10.30684/etj.26.10.13}, abstract = {The study introduces a theoretical analysis and numerical solution for the combustionof two kinds of hydrocarbon fuel droplet inside the combustion chamber. The study employsthree mathematical models to analyze the combustion process, conventional (classical) model,transient model, and moving droplet model. The combustion process of a stagnant droplet inthe steady state was analyzed in the classical model, while, in the transient model, it wasassumed that there is a period of time in the stages of the droplet combustion in which thedroplet is heated before combustion, For the moving droplet model, the film boundaryapproximation was incorporated to express the effects of the relative motion on the combustionprocess parameters. The effect of change in temperature on the thermo-physical properties ofthe fuel was adopted through the three models. For the classical and moving droplet models, aconvenient approximation was adopted for the heat transferred inside the droplet.Computer programs were created to evaluate the required properties, solving theordinary differential equations evaluated from heat and mass transfer balances, and thenconstruct systems of non-linear equations.The three models show that thermo physical properties are strong functions toreference temperature. The transient model shows that the period of droplet heat up is mosteffective. For the moving droplet combustion model it was shown that the relative movementbetween droplet and ambient surrounding gas enhanced the mass burning rate and reduced thedroplet lifetime. The film theory approach was adopted in moving droplet model.}, keywords = {Combustion,fuel droplet,models of combustion}, url = {https://etj.uotechnology.edu.iq/article_26859.html}, eprint = {https://etj.uotechnology.edu.iq/article_26859_fa31a807172361145d048e7bfa1d65c8.pdf} }