The ionospheric characteristics exhibit significant variations with the solar cycle, geomagnetic conditions, seasons, latitudes and even local time. Representation of this research focused on global distribution of electron (Te) and ion temperatures (Ti) during great and severe geomagnetic storms (GMS), their daily and seasonally variation for years (2001-2013), variations of electron and ion temperature during GMS with plasma velocity and geographic latitudes. Finally comparison between observed and predicted Te and Ti get from IRI model during the two kinds of storm selected. Data from satellite Defense Meteorological Satellite Program (DMSP) 850 km altitude are taken for Te, Ti and plasma velocity for different latitudes during great and severe geomagnetic storms from years 2001 to 2013 according to what is available appeared that there is 22 events for severe and great geomagnetic storms happened during years 2001-2005 only from years selected, from maximum solar cycle 23. From data analysis, in general the temperature of the electron is greater than the temperature of the ion, but there are some disturbances happened during the storm time, in the day there is fluctuation in values of Te and Ti with the value of Ti greater than Te. Through the Dst index, Te and Ti do not depend on the strength of the geomagnetic storm. Plasma velocity variation shows the same profile of Te and Ti variation during the storm time and there is a linear relation between (Te) & (Ti) and plasma velocity. The variation of electron and ion temperature with geographic latitude during severe and great storms appears that as the latitude increases the temperature of ions increases reaches its maximum value approximately 80000K at poles.
From comparing the predicted Te and Ti values calculating from IRI model during the great and severe storms with observed values, it’s found that the predicted values from IRI model much less than the observed values and the variation was nonlinear along 24 hours, from this we can conclude that the model must be corrected for Te and Ti for these two kinds of storms.
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Finite element modeling of transient temperature distribution is used to understand physical phenomena occurring during the dwell (penetration) phase and moving of welding tool in friction stir welding (FSW) of 5mm plate made of 7020-T53 aluminum alloy at 1400rpm and 40mm/min.
Thermocouples are used in locations near to the pin and under shoulder surface to study the welding tool penetration in the workpiece in advance and retreate sides along welding line in three positions (penetrate (start welding) , mid, pullout (end welding)).
Numerical results of ANSYS 12.0 package are compared to experimental data including axial load measurements at different tool rotational speeds (710rpm.900rpm.1120rpm and 1400rpm) Based on the experiment
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Inelastic longitudinal electron scattering form factors for second
excited state C42 in 42Ti nucleus have been calculated using shell
model theory. Fp shell model space with configuration (1f7/2 2p3/2
1f5/2 2p1/2) has been adopted in order to distribute the valence
particles (protons and neutrons) outside an inert core 40Ca. Modern
model space effective interactions like FPD6 and GXPF1 have been
used to generate model space vectors and harmonic oscillator wave
function as a single particle wave function. Discarder space (core
orbits + higher orbits) has been included in (core polarization effect)
as a first order correction in microscopic theory to measure the
interested multipole form factors via the model
Liquid membrane electrodes for the determination iron(III) were constructed based on chloramphenicol sodium succinate and iron(III) CPSS-Fe(III) as ion pair complex, with four plasticizers Di-butyl phosphate (DBP); Di-butyl phthalate (DBPH); Di-octyl phthalate (DOP); Tri-butyl phosphate (TBP); in PVC matrix . These electrodes give Nernstian and sub-Nernstian slopes (19.79, 24.60, 16.01 and 13.82mV/decade) and linear ranges from (1x10-5-1x10-2 M, 1x10-5-1x10-2 M, 1x10-6-1x10-2 M and 1x10-5-1x10-2 M) respectively. The best electrode was based on DBP plasticizer which gave a slope 19.79 mV/decade, correlation coefficient 0.9999, detection limit of 9×10-6 M, lifetime 37 day displayed good stability and reproducibility and used to determine
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Several industrial wastewater streams may contain heavy metal ions, which must be effectively removal
before the discharge or reuse of treated waters could take place. In this paper, the removal of copper( II)
by foam flotation from dilute aqueous solutions was investigated at laboratory scale. The effects of
various parameters such as pH, collector and frother concentrations, initial copper concentration, air flow
rate, hole diameter of the gas distributor, and NaCl addition were tested in a bubble column of 6 cm inside
diameter and 120 cm height. Sodium dodecylsulfate (SDS) and Hexadecyl trimethyl ammonium bromide
(HTAB) were used as anionic and cationic surfactant, respectively. Ethanol was used as frothers and the
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The mechanical properties and microstructure of hot-rolled steel are critical in determining its performance in industrial applications, particularly when exposed to elevated temperatures. This study examines the effects of varying temperatures and soaking times on these properties through a series of controlled experiments. The primary objective was to optimize the key response parameters, including tensile strength, yield strength, and elongation, by analyzing the influence of temperature and time. A full factorial design approach was used, applying the desirability function theory to explore all possible combinations and identify optimal processing conditions. The experimental results showed that the soaking time played a critica
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