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Modeling of Electron and Lattice Temperature Distribution Through Lifetime of Plasma Plume
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When employing shorter (sub picosecond) laser pulses, in ablation kinetics the features appear which can no longer be described in the context of the conventional thermal model. Meanwhile, the ablation of materials with the aid of ultra-short (sub picosecond) laser pulses is applied for micromechanical processing. Physical mechanisms and theoretical models of laser ablation are discussed. Typical associated phenomena are qualitatively regarded and methods for studying them quantitatively are considered. Calculated results relevant to ablation kinetics for a number of substances are presented and compared with experimental data. Ultra-short laser ablation with two-temperature model was quantitatively investigated. A two-temperature model for the description of transition phenomena in a non-equilibrium electron gas and a lattice under picosecond laser irradiation is proposed. Some characteristics are hard to measure directly at all. That is why the analysis of physical mechanisms involved in the ablation process by ultra-short laser pulses has to be performed on the basis of a theoretical consideration of `indirect' experimental data. For Copper and Nickel metal targets, the two-temperature model calculations explain that the temperature of the electron subsystem increased suddenly and approached a peak value at the end of laser pulse. In addition, the temperature profile of lattice temperature subsystem evolution slowly, and still increasing after the end of laser pulse. A good agreement prevails when a comparison between the present results and published results.

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Publication Date
Wed Jun 01 2011
Journal Name
Journal Of Engineering
ESTIMATION OF RELATIONSHIP BETWEEN COEFFICIENT OF CONSOLIDATION AND LIQUID LIMIT OF MIDDLE AND SOUTH IRAQI SOILS
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In this paper, a relationship between the liquid limit and the coefficient of consolidation of Iraqi soils are studied. The samples of soil used in study are undisturbed silty clay. These samples are taken from different locations and depths of Middle and South of Iraq by cooperation with Consulting Engineering Bureau- University of Baghdad- College of Engineering. The depth reached about 20 meters. The experimental work is made to calculate the liquid limit and the coefficient of consolidation. From these sites, 280 points are obtained. The relationship between the liquid limit and the coefficient of consolidation is drawn as a curve. This curve is studied and compared with the curve that obtained from other studies. From these curves, it

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Publication Date
Sun Sep 04 2016
Journal Name
Baghdad Science Journal
Surface-Subface Geochemical and Mineralogical Study of Gypcrete in Alexandria Area Central Iraq
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Gypsiferous soil deposits (Gypcrete) are weakly consolidate earthy mixture of secondary gypsum, sand and clay. It is formed in arid and semi- arid area with annual precipitation rainfall less than 400mm. These sediments occur in surface and subsurface in region of little rainfall and rapid evaporation. This research deals with the study of gypcrete in Alexandria to improve the mineralogical and geochemical properties of the gypcrete. The gypcrete soil is used as raw material to produce the plaster for building purposes. Three samples of gypcrete were chemically and geochemically analyzed. The common mineral is howed in 0-0.5m Gypsum followed by Calcite in 0-1m and Quartz in 1-1.5m due to leaching and infiltration by rainfall as well as it

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Publication Date
Wed Sep 30 2020
Journal Name
College Of Islamic Sciences
Arabization and its contemporary applications A jurisprudential study of the provisions and certifications of Arabization and migration
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The place in which the person lives and his geographical and social environment have a great impact on building his personality, belief and culture, Islam has alerted the importance of the Muslim to make sure to choose the appropriate place in which he resides and dwells in that it is compatible with his religion and belief in order to ensure communication with Islamic knowledge in a way that enhances his belief Arabization occurs when a person makes himself an Arab by living the life of the Bedouins, and creates the morals of the Bedouins from the inhabitants of the Badia with its harshness, cruelty, ignorance and lack of understanding in religion and far from the sources of knowledge of Islamic knowledge. Blasphemy and polytheism, and

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Publication Date
Sun Dec 31 2017
Journal Name
College Of Islamic Sciences
Sections of beliefs and area of endeavor
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Research summary

 


The researcher in theological sects finds that the controversial issues between the owners of the sects are many, filled with the books of the sects, articles and creeds, and when examining these books it became clear to us that the dispute is related, some of it is related to the meaning and some of it is related to the words and it is many, explained to us by rhetorical terminology such as guidance and delegation, Interpretation and others, and part of it is what is called the verbal disagreement, and sometimes it is by using common possible expressions of truth and falsehood, as in the saying of the Kharijites, “The judgment is only for God,” and some of it is related to something outside th

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Publication Date
Tue Sep 01 2015
Journal Name
Journal Of Engineering
Experimental Study on the Effect of Using Metallic Brushes on the Charging and Discharging Time of Thermal Energy Storage Unit
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Phase change materials are known to be good in use in latent heat thermal energy storage (LHTES) systems, but one of their drawbacks is the slow melting and solidification processes. So that, in this work, enhancing heat transfer of phase change material is studied experimentally for in charging and discharging processes by the addition of high thermal conductive material such as copper in the form of brushes, which were added in both PCM and air sides. The additions of brushes have been carried out with different void fractions (97%, 94% and 90%) and the effect of four different air velocities was tested. The results indicate that the minimum brush void fraction gave the maximum heat transfer in PCM and reduced the time

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Publication Date
Thu Apr 25 2019
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
SEPARATION OF PROTEIN AND LACTOSE FROM WHEY DISPOSED FROM ABO-GHRAAB DAIRY FACTORY BY USING MEMBRANE TECHNOLOGY: SEPARATION OF PROTEIN AND LACTOSE FROM WHEY DISPOSED FROM ABO-GHRAAB DAIRY FACTORY BY USING MEMBRANE TECHNOLOGY
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In this research, the performance of a two kind of membrane was examined to recovering the nutrients (protein and lactose) from the whey produced by the soft cheese industry in the General Company for Food Products inAbo-ghraab.Wheyare treated in two stages, the first including press whey into micron filter made of poly vinylidene difluoride (PVDF) standard plate type 800 kilo dalton, The membrane separates the whey to permeate which represent is the main nutrients and to remove the fat and microorganisms.The second stage is to isolate the protein by using ultra filter made of polyethylsulphone(PES)type plate with a measurement of 10,60 kilo dalton and the recovery of lactose in the form of permeate.
The results showed that the percen

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Publication Date
Sun Apr 01 2018
Journal Name
Journal Of Educational And Psychological Researches
Problems and needs of Baghdad university students from perspective of college of political sciences and college of engineering’s students
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The current research aims to identify the problems and needs for both college of political science and college of engineering’s students. The sample was (100) male and female student. The results showed bunch of problems which could be organized descendingly, the scientific domain ranged between (2 - 2.42), the mean of the psychological domain was (2.85), the moral domain ranged between (2.2 – 2.28)m the problems of study earned (2.30), the material domain got (1.95), the medical and social domain obtained (1.925), and finally, the family domain received (1.887).

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Publication Date
Tue Jun 14 2005
Journal Name
Iraqi Journal Of Laser
Design and Operation of Mini-TEA CO2 Laser and Investigation of Preionization Effect
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A Mini-TEA CO2 laser system was designed and operated to obtain a pulse at 10.6 μm. Output energy of 30 mJ, with preionization pins, and pulse duration of 100ns were obtained. While an output energy of 6mJ and pulse duration of 100 ns in absence of pre-ionization were obtained. The system was operated with Ernest profile main-discharge electrodes. Dependencies of supply voltage and output laser energy on the pressure inside laser cavity were investigated as well as dependencies of supply voltage and output energy on the main capacitor(8CO2 : 8N2 : 82He :2CO). Efficiency of was calculated to be 4.4%.

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Publication Date
Sun Jun 01 2008
Journal Name
Baghdad Science Journal
Effect of Nitrogen Fertilizer and Plant Density on Yield and Growth of Sunflower
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The effect of nitrogen fertilizer and the planting distance on growth and yield of the sunflower cultivar (Taka) was investigated. The experiment was conducted in the field using five nitrogen fertilizer levels (0, 50, 100, 150, 200) kg/donum and three planting distances (10, 20, 30) cm/plant. The experiment design was split-plot by using RCBD with four replicates. The level of fertilizer as the main plot, while the planting distance as the sub plot. Plant high and yield components were measured. Results indicated that using 200 kg/donum of nitrogen and 30 cm/plant of planting distance gave the highest rate of 1000 seeds weight and the number of seeds/ head. While using 200 kg/donum of nitrogen fertilizer with 10 cm/plant of planting dista

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Publication Date
Fri Dec 01 2023
Journal Name
Lxxvi Международная научно-практическая конференция «Научный форум: филология, искусствоведение и культурология»
Comparative analysis of the concept and types of homonyms in Russian and Arabic
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Abstract: This article is a comparative analysis of the concept and types of homonyms in Russian and Arabic. Homonyms are lexical units that have the same sound but different meanings. The study of homonymy in different languages can help reveal the features of the semantic structure and syntactic rules of each language. The article discusses the main aspects of homonymy in Russian and Arabic, as well as a comparative analysis of the types of homonyms that exist in both languages. The study includes an analysis of the semantic meanings of homonyms, their use in context, and possible differences in syntactic features that may affect their interpretation and perception by native speakers of these languages. The purpose of the article is to id

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