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 c
... Show MoreUrban Samarra City is characterized by high population density and wide variation in land use, has led to many environmental problems, for this purpose the environmental assessment became an urgent need for surface and ground water at study area. Three water samples from Tigris River and six groundwater samples were collected and analyzed for heavy metals as Fe, Mn, Zn, Cd, Cu, Co ,Pb, Ni, Cr, As, Mo, Hg, Al, Li, Be, Se, V, U, Sr. Most heavy metal concentrations have shown higher level than standards, such as Fe, Mn, Cd, Pb, Ni, Cr, As, Mo, Hg, Al ,Li ,Be, Se, V, that might be due to anthropogenic activities such as agricultural and the heavy use of fertilizers, besides other activities amo
... Show MoreThe Jabal Sanam, a piercement salt plug, represents a unique geological phenomenon in southern Iraq. It is a remarkable geological landmark that rises about 141 m above sea level and covers approximately 2 km2, surrounded by flat areas on all sides. A radiological survey was conducted on the Jabal Sanam structure to determine the natural radioactivity levels and related radiation hazard indices. Eleven different rock types from several locations at Jabal Sanam were collected. An optical microscope and X-ray diffraction (XRD) were used to examine and identify the variable rock types in this structure. Natural radioactivity using field and laboratory equipment for these rocks was measured. The findings indicated that the average
... Show MoreAge and growth of a population of Varicorhinus trutta (Heckel) from Tigris river at Salahuldin province have been investigated during the period from September 1999 to August 2000. A total of 156 fishes were collected from two stations at Tigris river using small meshed gill nets. The age data revealed that the species under investigation reached to a maximum age of seven years and approximately 46 cm long. The population of this species in Tigris river at the sites of study was dominated by 3 and 4 years classes. There were no marked differences in growth or longevity between the sexes. Determination of length-weight relationship revealed that the growth of both sexes in the species under investigation was allometric and the values of b
... Show MoreThe amicus curiae is one of the judicial procedures adopted in many judicial and legal systems around the world, under which a person who is not a party to the case, and without having a personal and direct interest in it, intervenes to draw the court’s attention to many factual and legal aspects
Hypothesis Nanofluid flooding has been identified as a promising method for enhanced oil recovery (EOR) and improved Carbon geo-sequestration (CGS). However, it is unclear how nanoparticles (NPs) influence the CO2-brine interfacial tension (γ), which is a key parameter in pore-to reservoirs-scale fluid dynamics, and consequently project success. The effects of pressure, temperature, salinity, and NPs concentration on CO2-silica (hydrophilic or hydrophobic) nanofluid γ was thus systematically investigated to understand the influence of nanofluid flooding on CO2 geo-storage. Experiments Pendant drop method was used to measure CO2/nanofluid γ at carbon storage conditions using high pressure-high temperature optical cell. Findings CO2/nano
... Show MoreA kindergarten teacher is one of the most important elements in the educational process, since she is totally relied upon in kindergartens. Therefore, she could have basic and healthy characteristics to improve the educational process by directing the child towards a perfect growing upEducating and raising up a child should be an organized process that makes desirable changes in the child’s behavior in order to improve different sides of his personality, such as his appearance side, his mental side, and his social side.
This research aims at:
1- Measuring the scientific brilliance in kindergarten teachers.
2- Investigating the statistical significant differences of the scientific brilliance among kindergarten teachers in accor
In this paper, ferric oxide nanoparticles) Fe2O3 NPs( were synthesized directly on a quartz substrate in vacuum by pulse laser deposition technique using Nd:YAG laser at different energies (171, 201,363 mJ/pulse). The slides were then heated to 700o C for 1 hour. The structural, optical, morphological, and electrical properties were studied. The optical properties indicated that the prepared thin films have an energy gap ranging from 2.28 to 2.04 eV. The XRD results showed no lattice impurities for other iron oxide phases, confirming that all particles were transformed into the α-Fe2O3 phase during the heating process. The AFM results indicated the dependence of nanoparticles size o
... Show MoreThe purpose of this work is to determine the points and planes of 3-dimensional projective space PG(3,2) over Galois field GF(q), q=2,3 and 5 by designing a computer program.
Eight soil samples were selected around Najaf governorate at depth levels 40-50 cm. X-Ray Fluorescence (XRF) was used to determine the concentrations of major and trace elements. Liner and mass attenuation coefï¬cient (µ, µÏ) have been determined at gamma energies (662, 1172,1332) keV using NaI (Tl) detector. The range of linear attenuation coefficients for calculated samples were (0.553-1.163) cm-1, (0.122-0.178) cm-1 and (0.049-0.105) cm-1 at (662, 1172,1332) keV respectively. The range of mass attenuation coefficients obtained (0.39-0.76) cm2/gm, (0.087-0.117) cm2/gm and (0.0336-0.074) cm2/gm at (662, 1172,1332) keV respectively. The result
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