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A review of ultra-high temperature materials for thermal protection system
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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>
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Publication Date
Sun Feb 24 2019
Journal Name
Iraqi Journal Of Physics
Design and evalution of a solar PV system
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PV connected systems are worldwide installed because it allows consumer to reduce energy consumption from the electricity grid. This paper presents the results obtained from monitoring a 1.1 kWp. The system was monitored for nine months and all the electricity generated was fed to the fifth floor for physics and renewable energy building   220 V, 50 Hz. Monthly, and daily performance parameters of the PV system are evaluated which include: average generated of system Ah per day, average system efficiency, solar irradiation around these months. The average generated kWh per day was 8 kWh/day, the average solar irradiation per day was 5.6 kWh/m2/day, the average inverter efficiency was 95%, the average modules efficien

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Publication Date
Mon Apr 20 2026
Journal Name
Journal Of Mechanics Of Continua And Mathematical Sciences
TRANSIENT THERMAL–MECHANICAL SIMULATION AND EXPERIMENTAL VALIDATION OF RESIDUAL STRESS IN HIGH-SPEED END MILLING OF STEEL USING ADAPTIVE MESH REFINEMENT AND DESIGN OF EXPERIMENTS BASED PROCESS OPTIMIZATION
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This study presents a transient thermo-mechanical finite element framework for high-speed end milling of AISI 4340 steel. The model couples moving heat sources, rate- and temperature-dependent plasticity, and adaptive mesh refinement (AMR) triggered by temperature gradient, plastic strain rate, and contact pressure. It is integrated with a design of experiments/response surface methodology using cutting speed (VC), feed per tooth (fZ), radial depth of cut/width of cut (ae), axial depth of cut (ap), and coolant mode. Responses include peak interface temperature per tooth (Tpeak), predicted surface residual stress (?_xx^"surf" ), and depth of compressive residual stress layer (dcomp). Experiments provide X-ray diffraction-based surfac

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Publication Date
Thu Nov 08 2018
Journal Name
Iraqi National Journal Of Nursing Specialties
Evaluation of National Standards for Exposure to Chemical Materials and Dusts in the State Company for Drugs Industry in Samarra
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Objective: Evaluation the national standards for exposure to chemical materials and dusts in The State
Company for Drugs Industry in Samarra.
Methodology: A descriptive evaluation design is employed through the present study from 25th May 2011
to 30th November 2011 in order to evaluate the national standards for exposure chemical materials and dusts
in The State Company for Drugs Industry in Samarra. A purposive (non-probability) sample is selected for the
study which includes (110) workers from the State Company for Drugs Industry in Samarra. Data were
gathered through the workers` interviewed according to the nature of work that they perform. The evaluation
questionnaire comprised of three parts which include the w

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Publication Date
Sun Jul 01 2012
Journal Name
Journal Of Educational And Psychological Researches
Self Protection and it's Relation with the social ignorance OF UNIVERSITY STUDENTS
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The aim of this research is to find a relation between self-protection and the social - ignorance of the univresity students. In applying the aims of the reaearch, the ressearcher has constructed two scales to measure
self - protection and the social - ignorance. After finding their validity and stability and their discriminative power, the researcher has applied them on a sample of (200) male and female. University students, who were selected randomly. The results of the research has arrived at finding a positive relation between self-protection and social - ignorance.

The researcher has recommended a concentration on the role of parents in raising their childern depending on themselves and making f

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Publication Date
Fri Apr 01 2022
Journal Name
Baghdad Science Journal
Protection of Galvanized steel from corrosion in salt media using sulfur nanoparticles
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                The characteristics of sulfur nanoparticles were studied by using atomic force microscope (AFM) analysis. The atomic force microscope (AFM) measurements showed that the average size of sulfur nanoparticles synthesized using thiosulfate sodium solution through the extract of cucurbita pepo extra was 93.62 nm. Protecting galvanized steel from corrosion in salt media was achieved by using sulfur nanoparticles in different temperatures. The obtained data of thermodynamic in the presence of sulfur nanoparticles referred to high value as compares to counterpart in the absence of sulfur nanoparticles, the high inhibition efficiency (%IE) and corrosion resistance were at high temperature, the corrosion rate or weig

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Publication Date
Sun Mar 01 2009
Journal Name
Al-khwarizmi Engineering Journal
Mass Transfer Coefficient During Cathodic Protection of Low Carbon Steel in Seawater
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The aim of this research is to calculate mass transfer coefficient, kd, during cathodic protection of low carbon steel in neutral seawater (3.5% W/V NaCl in distilled water with pH = 7). Two types of cathodic protection were used:

First: Sacrificial anode cathodic protection (SACP) were a pipeline of steel carrying seawater  using zinc as a sacrificial anode and with variable temperatures ranged (0 – 45oC) and volumetric flow rate ranged (5 – 900 lit/hr). It was found that the kd increases with increasing temperature and volumetric flow rate of seawater, where kd ranged (0.24×10-6 – 41.6×10-6 m/s).

Second: Impressed current cathodic pr

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Publication Date
Wed Nov 01 2023
Journal Name
Solar Energy
Optimizing performance of water-cooled photovoltaic-thermal modules: A 3D numerical approach
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To evaluate and improve the efficiency of photovoltaic solar modules connected with linear pipes for water supply, a three-dimensional numerical simulation is created and simulated via commercial software (Ansys-Fluent). The optimization utilizes the principles of the 1st and 2nd laws of thermodynamics by employing the Response Surface Method (RSM). Various design parameters, including the coolant inlet velocity, tube diameter, panel dimensions, and solar radiation intensity, are systematically varied to investigate their impacts on energetic and exergitic efficiencies and destroyed exergy. The relationship between the design parameters and the system responses is validated through the development of a predictive model. Both single and mult

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Publication Date
Wed Feb 01 2023
Journal Name
Baghdad Science Journal
Synthesis, Characterization, and Thermal Analysis of a New Acidicazo Ligand's Metal Complexes
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The researchers wanted to make a new azo imidazole as a follow-up to their previous work. The ligand 4-[(2-Amino-4-phenylazo)-methyl]-cyclohexane carboxylic acid as a derivative of trans-4-(aminomethyl) cyclohexane carboxylic acid diazonium salt, and synthesis a series of its chelate complexes with metalions, characterized these compounds using a variety technique, including elemental analysis, FTIR, LC-Mass, 1H-NMRand UV-Vis spectral process as well TGA, conductivity and magnetic quantifications. Analytical data showed that the Co (II) complex out to 1:1 metal-ligand ratio with square planner and tetrahedral geometry, respectively while 1:2 metal-ligand ratio in the Cu(II), Cr(III), Mn(II), Zn(II), Ru(III)and Rh(III)complexes

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Publication Date
Thu Oct 01 2020
Journal Name
Engineering Science And Technology, An International Journal
Thermal performance improvement based on the hybrid design of a heat sink
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Publication Date
Mon Jan 02 2023
Journal Name
Baghdad Science Journal
Synthesis, Characterization, and Thermal Analysis of a New Acidicazo Ligand's Metal Complexes
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The researchers wanted to make a new azo imidazole as a follow-up to their previous work. The ligand 4-[(2-Amino-4-phenylazo)-methyl]-cyclohexane carboxylic acid as a derivative of trans-4- (aminomethyl) cyclohexane carboxylic acid diazonium salt, and synthesis a series of its chelate complexes with metalions, characterized these compounds using a variety technique, including elemental analysis, FTIR, LC-Mass, 1H-NMRand UV-Vis spectral process as well TGA, conductivity and magnetic quantifications. Analytical data showed that the Co (II) complex out to 1:1 metal-ligand ratio with square planner and tetrahedral geometry, respectively while 1:2 metal-ligand ratio in the Cu(II), Cr(III), Mn(II), Zn(II), Ru(III)and Rh(III)complexes with octahed

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