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Effect of Quenching Media Variations on the Mechanical Behavior of Martensitic Stainless Steel
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The purpose of this study is designate quenching and tempering heat treatment by using Taguchi technique to determine optimal factors of heat treatment (austenitizing temperature, percentage of nanoparticles, type of base media, nanoparticles type and soaking time) for increasing hardness, wear rate and impact energy properties of 420 martensitic stainless steel. An (L18) orthogonal array was chosen for the design of experiment. The optimum process parameters were determined by using signal-to-noise ratio (larger is better) criterion for hardness and impact energy while (Smaller is better) criterion was for the wear rate. The importance levels of process parameters that effect on hardness, wear rate and impact energy properties were obtained by using analysis of variance which applied with the help of (Minitab18) software. The variables of quenching heat treatment were austenitizing temperature (985 C˚,1060 C˚),a soaking times (50,70 and 90 minutes) respectively, Percentage of volumetric fractions of nanoparticles with three different levels(0.01, 0.03 and 0.08 %) were prepared by dispersing nanoparticles that are  (α-Al2O3,TiO2 and CuO) with base fluids (De-ionized water, salt solution and engine oil).The specimens were tempered at 700°C after quenching of nanofluids for  (2 hours).The results for ( S/N) ratios showed the order of the factors in terms of the proportion of their effect on hardness, and wear rate  properties as follow: Austenitizing temperature ( 1060 C˚),Type of base media (salt solution), Nanoparticles type (CuO), Percentage of nanoparticles (0.08%) and Soaking time(90min) was the least influence while for the impact energy were as follows: Type of base media (oil), Austenitizing temperature (985C˚), Percentage of nanoparticles (0.01%), Nanoparticles type (α-Al2O3) and last soaking time (50min).

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Publication Date
Wed Mar 30 2022
Journal Name
College Of Islamic Sciences
"Explanation of the Fundamentals for Al-Bazdawi" Study and Investigation (From the beginning of Prohibition Chapter to its End)
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This research addresses: Sharh Usul Al-Bazdawi "Explanation of the Fundamentals for Al-Bazdawi", by studying and investigating, from the beginning of prohibition chapter to its end. The researcher conducted a study about this book stating its significance and introducing the compiler and the commentator. The researcher as well mentioned that the prohibition has a special formula and requires repetition, and he went on explaining that prohibition according to Hanafis does not require absolute corruption of the prohibited matter unless based on an evidence, and that what is condemned as wrong act for itself is considered void and what is condemned as wrong act for external reasons is considered corrupt accor

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Publication Date
Fri Apr 01 2016
Journal Name
Al–bahith Al–a'alami
Trends of University Professors towards the Role of Social Networking Websites in Shaping Public Opinion about the Security Crises
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Social networking sites represent one of the modern communication technologies that have contributed to the expression of public opinion trends towards various events and crises of which security crisis is most important being characterized by its ability to influence the community life of the public. In order to recognize its role in shaping opinions of the educated class of the public that is characterized by a high level of knowledge, culture and having experience in dealing with the media. Its advantage is that they have an active audience by expressing their views on the situations, events, and news published on them as well as expressing their attitudes and sympathy with the events. So a number of questions are included in the ques

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Publication Date
Wed Mar 30 2022
Journal Name
Journal Of Educational And Psychological Researches
Employing electronic supervision applications in developing the teaching performance of teachers in the Sultanate of Oman: a suggested vision
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The study aimed to investigate the employment of electronic supervision applications in developing the teaching performance of teachers in Oman. Based on the qualitative method and the study population consisted of all the teachers of the first cycle in the Governorate of Muscat. The study sample amounted to 24 female teachers. The interview was used as a tool for data collection. The study reached several results, including: There are difficulties in employing electronic supervision applications, which are weak network, density of curricula, lack of experience in applying technology, and the large number of tasks assigned to the teacher. These difficulties can also be overcome by strengthening the network, training teachers, reducing th

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Publication Date
Fri Dec 01 2017
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
SEASONAL POPULATION ABUNDANCE OF THE CHRYSANTHEMUM APHIDS (HOMOPTERA, APHIDIDAE) IN THE MIDDLE OF IRAQ WITH PICTORIAL KEY TO SPECIES
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    This study was based on the determination of aphid species that infested Chrysanthemum sp. (Asterales, Asteraceae) in the middle of Iraq; five aphid species belong to subfamily Aphidinae were recorded: Aphis fabae Scopoli, 1763, Aphis gossypii Glover, 1877,  Coloradoa rufomaculata (Wilson, 1908), Macrosiphoniella sanborni (Gillette, 1908) and Myzus persicae (Sulzer, 1776). A. gossypii was the most dominant species throughout the study period while M. persicae  is the lesser species.

    A summary of  the main taxonomic characters is presented here and a pictorial key which was designed to separate aphi

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Publication Date
Mon Jan 28 2019
Journal Name
Iraqi Journal Of Science
Using of Ground Penetrating Radar (GPR) for investigate the subsurface archaeological features of Babylon, the ancient city (Mounts zoona)
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Ground Penetrating Radar (GPR) method has been used in the province of Babylon, the ancient city  (constituted mounts zoona) archeological site The study area is located South of the city of Hilla by 40 km   between longitudes 44˚ 24΄ 40˝ E to 44˚ 27΄ 00˝ E, and latitudes 32˚ 31΄ 10 ˝ N to 32˚ 33΄ 00˝ N,

The type of GPR that used in the survey fieldwork was of Malå Geoscience / Sweden type (RAMAC /GPR). The constituted mounts zoona  district  are surveyed using Seventy – four  parallel profiles trending S-N ,N-S , E-W and W-E using the available antenna 160 MHz and 450 MHz, with Five meter spacing between each other are acquired the round-trip survey was conducted for ease and speed of

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Publication Date
Wed Dec 14 2016
Journal Name
Journal Of Baghdad College Of Dentistry
Comparison of the Marginal Fitness of the Ceramic Crowns Fabricated with Different CAD/CAM Systems (An In Vitro Study)
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Background: The marginal fit is the most characteristic that closely related to the longevity or success of a restoration, which is absolutely affected by the fabrication technique. The objective of present in vitro study was to evaluate the effect of four different CAD/CAM systems on the marginal fit of lithiµm disilicate all ceramic crowns. Materials and Methods: Adentoform tooth of a right mandibular first molar was prepared to receive all ceramic crown restoration with deep chamfer finishing line (1mm) and axial reduction convergence angle of 6 degree, dentoform model duplicated to have Nickel-Chromiµm master die. Thirty two stone dies produce from master die and distributed randomly in to four groups (8 dies for each group) accor

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Publication Date
Sun Jul 02 2023
Journal Name
Iraqi Journal Of Science
Determination of the Shape and Dimensions of the Sensitive Volume for Solid State Detectors Using Monte Carlo Computer Technique
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In this research the active volume for a number of solid-state detectors of the type of high-purity germanium (HPGe) crystal was evaluated with different radii and depths using scanning method for diagonal (front) and lateral (side). It has been used for this purpose Monte-Carlo efficiency program after its development by adding a subroutine-program for its (subroutine scanning).Also a program has been written to calculate the stopping power and range for incident charged particle on the detector, in order to determine the exact sufficient energy to stop it inside the detector material. The calculations of our results of efficiency were compared with the results of published efficiency and the comparison is very good in terms of improvin

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Publication Date
Mon Mar 07 2022
Journal Name
Journal Of Educational And Psychological Researches
Analytical Study of Mathematics Textbooks in the Basic Education Stage in the Sultanate of Oman According to NCTM Standards
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The present study aimed to identify the availability of the National Council of Teachers of Mathematics (NCTM) standards in the content of mathematics textbooks at the basic education stage in the Sultanate of Oman. The study used the descriptive-analytical approach, adopting the method of content analysis through using a content analysis tool that included (43) indicators distributed on the four NCTM standards related to the field of geometry, after verifying their validity and reliability. The study population consisted of mathematics textbooks (first and second semesters) for ninth-grade students in the Sultanate of Oman in the academic year 2018/2019, while the sample consisted of Geometry units in the content of those books, which a

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Publication Date
Fri Dec 01 2023
Journal Name
Iraqi Journal Of Physics
Study of the Symmetry Energy and the Nuclear Equation of State for 13O -13B and 13N-13C Mirror Nuclei
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In parallel with the shell model using the harmonic oscillator's single-particle wave functions, the Hartree-Fock approximation was also used to calculate the neutron skin thickness, the mirror charge radii, and the differences in proton radii for 13O-13B and 13N-13C mirror nuclei. The calculations were done for both mirror nuclei in the psdpn model space. Depending on the type of potential used, the calculated values of skin thickness are affected. The symmetry energy and the symmetry energy's slope at nuclear saturation density were also determined, and the ratio of the density to the saturation density of nuclear matter and the symmetry energy has a nearly linear correlation. The mirror ener

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Publication Date
Mon Dec 20 2021
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
MORPHOLOGY AND MOLECULAR IDENTIFICATION OF THE LARVAL STAGE OF TWO SPECIES FROM THE GENUS CHRYSOBOTHRIS ESCHSCHOLTZ, 1829 (COLEOPTERA, BUPRESTIDAE)
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The genus of Chrysobothris Eschscholtz, 1829 is one of the most diverse and widespread genera of the family Buprestidae of some 700 described species distributed throughout the world. In Iraq, particularly in the Kurdistan region, about 4 species had been recorded so far, many of these species are sympatric, share larval host plants, and are difficult to reliably separate morphologically. The current study investigates species limits and relationships among the recognized species occurring within the Erbil Province; mitochondrial cytochrome C oxidase (COX I) molecular analysis confirmed the monophyly of two Chrysobothris species, Ch. affinis (Fabricius, 1794) and Ch. chrysostigma (Linnaeus, 1758). Implications of the resultant larval mor

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