Preferred Language
Articles
/
6xaZHooBVTCNdQwCHJAn
A review of ultra-high temperature materials for thermal protection system
...Show More Authors
Abstract<p>Ultra-High Temperature Materials (UHTMs) are at the base of entire aerospace industry; these high stable materials at temperatures exceeding 1600 °C are used to manage the heat shielding to protect vehicles and probes during the hypersonic flight through reentry trajectory against aerodynamic heating and reducing plasma surface interaction. Those materials are also recognized as Thermal Protection System Materials (TPSMs). The structural materials used during the high-temperature oxidizing environment are mainly limited to SiC, oxide ceramics, and composites. In addition to that, silicon-based ceramic has a maximum-use at 1700 °C approximately; as it is an active oxidation process over low temperature and water vapor environment condition. However, a great emphasis is required for developing structural materials in oxidation and rapid heating environment where the temperature is greater than 1700 °C. This review covers briefly all main types of Thermal Protection Systems (TPSs) and all the materials are used to fabricate them with the maximum operational temperatures. Also, it covers the promised UHTMs (SiC, ZrB<sub>2</sub>, HfB<sub>2</sub>, SiB<sub>6</sub> and B<sub>4</sub>C) which are currently using for several aerospace applications, especially for TPS. Besides, it discusses the oxidation of SiC, B<sub>4</sub>C, SiB<sub>6</sub>, ZrB<sub>2</sub> and HfB<sub>2</sub>. Therefore, the carbides and borides of the transition metals, Zr and Hf have a high-melting temperature and good stability in forming high-melting temperature oxides.</p>
Scopus Clarivate Crossref
View Publication
Publication Date
Tue Mar 28 2017
Journal Name
Archives Of Polish Fisheries
Meristic character variability among populations of Silurus triostegus Heckel, 1843 from the Euphrates, Tigris, and Shatt al-Arab Rivers, Iraq
...Show More Authors
Abstract<p>Variation in the numbers of pectoral fin spines and rays, pelvic fin rays, gill rakers on the first gill arch, anal fin rays, and the number of vertebrae of Silurus triostegus Heckel were examined in specimens from 16 localities that span its entire distribution range in the Tigris, Euphrates, and Shatt al-Arab rivers in Iraq. The mean number of the six meristic traits increases toward high latitudes with maximum and minimum values in the north and south of Iraq. Based on cluster analysis and PCA, the Mesopotamian river samples were clearly separated into three distinct groups. The upper Tigris populations were isolated from those of the middle and southern populations of this river and from those of</p> ... Show More
View Publication
Scopus (5)
Crossref (8)
Scopus Crossref
Publication Date
Mon May 31 2021
Journal Name
Indian Journal Of Ecology
Identification and Antimicrobial Susceptibility Profiles of Salmonella spp. Isolated from Chicken Flocks and their Feed and Water in Karbala, Iraq
...Show More Authors

The objective of study was determining the most prevalent Salmonella spp. and their antimicrobial susceptibility in broilers and laying chickens and their feed and drinking water in five chicken farms in Karbala, Iraq over the period from August to October 2020. A total of 289 samples, including 217 cloaca swabs, 46 water and 26 feed samples were collected. Salmonella spp. was identified firstly by routine diagnostic methods, followed by applying the API 20E kit, the Vitek2 system, and serology. There was significant differences in Salmonella prevalence among different types of samples, mainly cloaca swabs reported a high isolation rate (21.7%). In contrast, feed samples were completely free of contamination. The highest rate of isolation w

... Show More
Preview PDF
Publication Date
Fri Sep 01 2023
Journal Name
Journal Of Optics
Structural and optical properties of C60-ZnO thin films synthesized by spray pyrolysis technique with plasma treatment as antibacterial activity
...Show More Authors

Spray pyrolysis technique was used to make Carbon60-Zinc oxide (C60-ZnO) thin films, and chemical, structural, antibacterial, and optical characterizations regarding such nanocomposite have been done prior to and following treatment. Fullerene peaks in C60-ZnO thin films are identical and appear at the same angles. Following the treatment of the plasma, the existence regarding fullerene peaks in the thin films investigated suggests that the crystallographic quality related to C60-ZnO thin films has enhanced. Following plasma treatment, field emission scanning electron microscopy (FESEM) images regarding a C60-ZnO thin film indicate that both zinc oxide and fullerene particles had shrunk in the size and have an even distribution. In addition

... Show More
View Publication
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Sat Sep 01 2018
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The role of risk management programs in Dealing With risks at international airports: An Applied research at Baghdad International Airport
...Show More Authors

The objective of the research is to identify the efficiency of risk management in various names at Baghdad International Airport in the face of various risks (financial - technical - human - natural ..) facing the sample of the search of the General Establishment of Civil Aviation and the Iraqi Airways Company where the researcher identified the hypothesis that summarizes There is a significant significant correlation between risk management, risk management and risk review and assessment. The researcher used the means of research from observation and interviews with the relevant officials in this field, as well as used the questionnaire and distributed a sample of 170 employees in the field of risk management (SMS Department) in Iraqi A

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Oct 10 2017
Journal Name
مجلة كلية التربية الاساسية/الجامعة المستنصرية
Detection of some major elements and protein in Fusarium wilt disease infected tomato(Lycopersicon esculentum) treated with Arbuscular mycorrhizal fungi
...Show More Authors

Abstract The present study was Conducted to evaluate the effect of amixture of three species of arbuscular mycorrhizal fungi ( Glomus etunicatum , G. leptotichum and Rhizophagus intraradices ) in Influence on the percentage of the components of NPK and protein of tomato leaves and roots infected with Fusarium oxysporum f.sp. Lycopersici wich cause Fusarial wilt disease , planted for 8 weeks in the presence of the organic matter ( peatmose) , using pot cultures in aplastic green house , Results indicated significant increase in the percentage of the elements of NK and protein of tomato leaves and roots In the control treatment (C), While the percentage of the element P was after infection with the pathogen 4 weaks after mycorrhiza

... Show More
Publication Date
Fri Jun 30 2023
Journal Name
Journal Of The College Of Education For Women
Developing Tenth Grade Female Students' Attitudes in Critical Reading Skills Using the Reflective Thinking Method in the Sultanate of Oman
...Show More Authors

        This study aimed to developing the skills of critical reading for the tenth basic school female students through a training program using the reflective thinking method. The study sample consisted of (64) students. To achieve the objective of the study, the researcher uses the quasi-experiment approach consisting of a control group (32 students) and an experimental group (32 students). The researcher used three research inventories as follows: 1) A list of critical reading skills included (30) skills within three aspects (Recognition – Deduction – Evaluation and Judgment). 2) An executive program using reflective thinking for developing critical reading skills. 3) Achievement test to measure

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Jun 30 2015
Journal Name
College Of Islamic Sciences
From the responses of Imam Abi Zakaria al-Nawawi 676 AH on the grammarians in his commentary on Sahel Muslim
...Show More Authors

From the responses of Imam Abi Zakaria al-Nawawi 676 AH on the grammarians in his commentary on Sahel Muslim

View Publication Preview PDF
Publication Date
Sat Feb 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
Application Effect of the Conflict Management Strategies On Increasing Workers Productivity at the Electricity Company (IGEC) (Field Study Irbid Governorate)
...Show More Authors

Research aimed to explore the Application Effect of the Conflict Management Strategies by the managements to solve conflict between and inside the conflicted parties within (IGEC) to increase the productivity of the workers. To collect data, 110 questioners had been distributed among managers and heads of departments of all managerial levels, 102 answered questioners regained, 5 of them were disqualify for statistical analytic, only 97 were taking in consideration   for statistical analysis presenting 93% of the retained number.

SPSS Program supported with a group of statistical tools, had been used for analysis purposes such as Kronbach Alpha test to assure the validity & stability of the t

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Feb 07 2019
Journal Name
Iraqi Journal Of Laser
An In Vitro Histological Study of Human Skin Wound Soldering Using 980 nm Diode Laser in Continuous versus Pulsed Modes.
...Show More Authors

Laser skin wound soldering offers many distinct advantages over conventional closure and laser welding techniques. Objective : to compare the histological effects of human skin wound soldering using 50 % human albumin solder and compound charcoal photosensitiser with 980 nm diode laser acting in various modes of action and parameters. Study Design/Materials and Methods: In this in vitro experimental study , Multiple 3-4 cm long full thickness incisions in a specimen of human skin were soldered using a 4 mm spot diameter beam of 980 nm diode laser(at different laser parameters and modes of action) with 50 % human albumin solder mixed with the compound charcoal at 5 % W/V concentration .After obtaining a successful wound soldering , the wo

... Show More
View Publication Preview PDF
Publication Date
Wed Sep 01 2021
Journal Name
Iraqi Journal Of Physics
Matter Density Distributions, Root-mean Square Radii and Elastic Electron Scattering Form Factors of Some Exotic Nuclei (17B, 11Li, 8He)
...Show More Authors

The two-neutron halo-nuclei (17B, 11Li, 8He) was investigated using a two-body nucleon density distribution (2BNDD) with two frequency shell model (TFSM). The structure of valence two-neutron of 17B  nucleus in a pure (1d5/2) state and in a pure (1p1/2) state for  11L and 8He nuclei. For our tested nucleus, an efficient (2BNDD's) operator for point nucleon system folded with two-body correlation operator's functions was used to investigate nuclear matter density distributions, root-mean square (rms) radii, and elastic electron scattering form factors. In the nucleon-nucleon forces the correlation took account of

... Show More
View Publication Preview PDF
Crossref