Preferred Language
Articles
/
ijp-844
Determination of Skip Entry Trajectories for Space Vehicles at Circular and Super Circular Speeds
...Show More Authors

The study of entry and reentry dynamics for space vehicles is very important, particularly for manned vehicles and vehicles which is carry important devices and which can be used again. There are three types for entry dynamic, ballistics entry, glide entry and skip entry. The skip entry is used in this work for describing entry dynamics and determining trajectory. The inertia coordinate system is used to derive equations of motion and determines initial condition for skip entry. The velocity and drag force for entry vehicle, where generate it during entry into earth’s atmosphere are calculated in this work. Also the deceleration during descending and determining entry angles, velocities ratio and altitude ratio have been studied. The circular velocity and super circular velocity are used in this work as initial values. From results we noted the skip entry type has longer flight time compared with other types, and the velocity vehicle is lower at high layer for earth atmosphere, where the density of air is very low. Therefore the skip entry is suitable for space shuttle during entry from space

View Publication Preview PDF
Quick Preview PDF
Publication Date
Sat Jan 01 2022
Journal Name
Optik
Plasma parameters of Au nano-particles ablated on porous silicon produced via Nd-YAG laser at 355 nm for sensing NH3 gas
...Show More Authors

a laser ablation Q-switched Nd: YAG laser with a wave-length of 355 nm at a variety of laser pulse energies (E) and deposited on porous silicon (PS). Optical emission spectrometer was used to diagnosed medium air to study gold plasma characteristics and prepared Au nanoparticles. The laser pulse energy influence has been studied on the plasma characteristics in air. The data showed the emergence of the ionic (Au II) spectral emission lines in the gold plasma emission spectrum. XRD has been utilized to examine structural characteristics. Moreover, AFM results 37.2 nm as the mean value of the diameter that is coordinated in a shape similar to the rod that appears for Au NPs, in addition to that, TEM has been an indication of the fact that syn

... Show More
View Publication
Scopus (38)
Crossref (33)
Scopus Clarivate Crossref
Publication Date
Tue Oct 02 2018
Journal Name
Iraqi Journal Of Physics
Measurement of indoor radon levels and assessment of radiological hazards at Al-Tuwaitha nuclear site and the surrounding area
...Show More Authors

In the present study the radon concentration was measured in indoor places by the RAD7 (radon detector) was in some locations at Al-Tuwaitha nuclear site and some surrounding areas for the duration from 13/10/2016 to 2/1/2017 and the measurement of the indoor radon concentration ranged from (4.96±4.4 to 102±25) Bq/m3. The high value of radon has been found at decommissioning directorate /emergency room, which is lower than the action value recommended by the Environmental Protection Agency (EPA) which is (148 Bq/m3) while the lowest value has been founded in central laboratories directorate \ models room. These values were used to calculate the annual effective dose and the health risks for cells bronchial which caused by the inhalatio

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Oct 02 2013
Journal Name
Journal Of The College Of Basic Education
Excess parameters of binary mixtures of tetrahydrofurfuryl alcohol with cyclopentanol and 1-pentanol at (293.15, 303.15 and 313.15 K)
...Show More Authors

Publication Date
Wed Jun 07 2023
Journal Name
Journal Of Educational And Psychological Researches
The Effectiveness of a Program in Developing Awareness of the Criteria for Judging Electronic Educational Materials Among Students of Teaching Diploma at Dhofar University
...Show More Authors

The study aims to develop the awareness of the criteria for judging electronic educational materials among students of educational qualification at Dhofar University over spreading the Corona pandemic through a program based on mini-educational units. The study was applied to (18) students studying Teaching diploma at Dhofar University for the academic year 2020-2021, and their number. They were chosen intentionally. The study resulted in reaching a list of criteria for judging electronic educational materials, roughly (18) criteria in the selection themes and (15) criteria in the use theme. The level of awareness of the sample members with the criteria for selecting and using electronic educational materials and the effectiveness of the

... Show More
View Publication Preview PDF
Publication Date
Wed Jan 01 2020
Journal Name
Indian Journal Of Forensic Medicine And Toxicology
Continuous Flow Injection Analysis,Turbidmetric and Photometric Determination of Methyldopa Using a New Long Distance Chasing Photometer (NAG-ADF-300-2)
...Show More Authors

A specific, sensitive and new simple method was used for the determination of methyldopa in pure and pharmaceutical formulations by using continuous flow injection analysis. This method is based on formation of ion pair compound between methyldopa and potassium hexacyanoferrate in acidic medium to obtain a yellow precipitate complex using long distance chasing photometer (NAG-ADF-300-2). The linear range for calibration graph was 0.05-35 mmol/L for cell A and 0.05-25 mmol/L for cell B, and LOD 1.4292 µg /200 µL for both cells with correlation coefficient (r) 0.9981 for cell A and 0.9994 for cell B, RSD% was lower than 0.5 % for n=8 for. The results were compared with classical method UV-Spectrophotometric at λ max=280 nm and turbi

... Show More
Scopus (4)
Crossref (2)
Scopus Crossref
Publication Date
Sun Dec 07 2008
Journal Name
Baghdad Science Journal
New Method for Determination of Molybdenum(VI) through Flow Injection Analysis Via the Consumption of Liberated Oxygen from Reaction System Ammonia-Hydrogen peroxide-Molybdenum(VI) in the Presence of Pyrogallol
...Show More Authors

This piece of research work aims to study one of the most difficult reaction and determination due to continuous and rapid variation of reaction products and the reactants. As molybdenum (VI) aid in the decomposition of hydrogen peroxide in alkaline medium of ammomia, thus means a continuous liberation of oxygen which cuases and in a continuous manner a distraction in the measurement process. On this basis pyrogallol was used to absorbe all liberated oxygen and the result is an a clean undisturbed signals. Molybdenum (VI) was determined in the range of 4-100 ?g.ml-1 with percentage linearity of 99.8% or (4-300 ?g.ml-1 with 94.4%) while L.O.D. was 3.5 ?g.ml-1. Interferring ions (cations and anions) were studied and their main effect was red

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Dec 31 2016
Journal Name
Al-kindy College Medical Journal
Dorsal plication during penile orthoplasty with and without neurovascular bundle mobilizationA comparative clinical trial conducted At Ghazy Al-Hariri teaching hospital for surgical specialties (2013 –2015)
...Show More Authors

Background: Dorsal plication on each side of the penis at the 2 and 10-o’clock positions had been a mainstay for correction of ventral penile curvature. However, because only the 12-o’clock position proved to be a nerve-free zone, dorsal plication at the 12-o’clock position can be advocated.

Objectives: To evaluate tunica albuginea plication with and without neurovascular bundle mobilization in patients with ventral penile curvature. Type of the study: A prospective study.

Methods: A 34 patients with a mean age of (4.8 ± 0.54) years, Who still

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Sep 30 2011
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Vapor-Liquid-Liquid Equilibrium (VLLE) Data for the Systems Ethyl acetate + Water, Toluene + Water and Toluene + Ethyl acetate + Water at 101.3 kPa. Using Modified Equilibrium Still
...Show More Authors

Isobaric Vapor-Liquid-Liquid equilibrium data for the binary systems ethyl acetate + water, toluene + water and the ternary system toluene + ethyl acetate + water were determined by a modified equilibrium still, the still consisted of a boiling and a condensation sections supplied with mixers that helped to correct the composition of the recycled condensed liquid and the boiling temperature readings in the condensation and boiling sections respectively. The VLLE data where predicted and correlated using the Peng-Robinson Equation of State in the vapor phase and one of the activity coefficient models Wilson, NRTL, UNIQUAC and the UNIFAC in the liquid phase and also were correlated using the Peng-Robinson Equation of State in both the vapo

... Show More
View Publication Preview PDF
Publication Date
Mon Sep 20 2021
Journal Name
Key Engineering Materials
Heat Treatment at Different Temperatures and its Effect on the Optical Properties of Pure PMMA and PMMA-Coumarin
...Show More Authors

The effect of thermal treatment on optical constants of pure PMMA and with addition (15 and 35) ml of coumarin at different temperatures (100, 110 and 120) C0 for 1 hour were investigated. Cast method used to prepares films of pure PMMA and PMMA with (15 and 35) of coumarin. UV/VIS spectrometer technique used to measure the absorption spectra for these films. The optical constant (absorption spectra and absorption coefficient) don’t changes after applied temperatures in pure PMMA film but the optical constant (absorption spectra and absorption coefficient) in PMMA with (15 and 35) ml of coumarin increased with applied temperatures. The optical energy gap of pure PMMA and PMMA with (15 and 35) ml of coumarin sl

... Show More
View Publication
Scopus (8)
Crossref (5)
Scopus Crossref
Publication Date
Sun Jun 03 2018
Journal Name
Baghdad Science Journal
Degradation of Dazomet by Thermal Fenton and Photo-Fenton Processes under UV and Sun lights at Different Temperatures
...Show More Authors

In this research, the degradation of Dazomet has been studied by using thermal Fenton process and photo-Fenton processes under UV and lights sun. The optimum values of amounts of the Fenton reagents have been determined (0.07g FeSO4 .7H2O, 3.5µl H2O2) at 25 °C and at pH 7 where the degradation percentages of Dazomet were recorded high. It has been found that solar photo Fenton process was more effective in degradation of Dazomet than photo-Fenton under UV-light and thermal Fenton processes, the percentage of degradation of Dazomet by photo-Fenton under sun light are 88% and 100% at 249 nm and 281 nm respectively, while the percentages of degradation for photo-Fenton under UV-light are 87%, 96% and for thermal Fenton are 70% and 66.8% at 2

... Show More
View Publication Preview PDF
Scopus Clarivate Crossref