As a star explode as a supernova its ejecta will directly interact with relativelylow density interstellar medium with high shock wave velocity, and due to thisinteraction many of forbidden emission lines will give a raise from both theexcitation and ionization of the atom in the region. So, the study of these emissionlines can reveal many physical properties of the region, in this case the remnant ofthe supernova, such as temperature, density, composition, and many other importantphysical processes. In this paper the optical spectrum of the young galacticsupernova remnant which is the Crab Nebula has used, in order to calculate it’selectron temperature (Te) and electron density (ne) by using the [OIII] and [SII]forbidden lines. From the obtained results it’s found that, the remnant has Te reach to17,000 500°K that raises from high shock velocity according to the intensity ratioof which is found to be , although the remnant has suchhigh Te and high shock velocity it’s found that, only about 64% of pre-shock heliumis fully pre-ionized in the remnant. In addition to that when the intensity ratio ofboth [ ] and [SII] lines has taken it’s found that, the remnant is an intermediatedensity remnant which has ne equal to 1300 10 cm-3
Background: Recurrent aphthous ulceration (RAU) is an inflammatory condition of unknown etiology characterized by painful recurrent (single or multiple) ulcerations of the oral mucosa. It is one of the most common and poorly understood mucosal disorders. It occurs more frequently in times of stress. Local and systemic conditions, genetic, immunologic, microbial factors, and oxidative stress may play a role in the pathogenesis of RAU. The objective of this study was to evaluate the free radical metabolism and antioxidant activity of RAU patients treated by lavender or flax oil paint.
Materials and Methods: Sixty-six RAU patients were enroll
... Show MoreThe species of Cr (III), Cr (VI) in biological samples and V(IV), V(V) in foods & plants samples were determined by spectrophotometric methods. Integrated spectral studies of complexes [Cr (III, VI)-DPC], [Cr (VI)-bipy], [VO-SH], [V (V)-8-HQ] which included a study of the optimum conditions for the complexes formation by the investigation of the chemical and physical variables affecting each complex formation, the nature of complexes, the preparation of calibration curves of the complexes and treated the resulted data by modern statistical methods and study the interfering species. Interferences were removed to explain the reactions thermodynamically by determining Ecell, Keq. and ∆G values and includes a study of
... Show MoreCO2 laser (10.6 μm) is the most often used laser in the oral surgery due to its high absorption by water of the oral tissues. Several benefits of the use of CO2 laser have been reported for oral surgical procedures. This study aims to evaluate the effect of CO2 laser on soft and hard oral tissues (in vitro study). This study was done on fresh tissues from sheep’s head. CO2Surgical Laser with different operation modes was used; 0.2 mm spot size using different laser parameters on the tongue, and bone making holes, incisions and cutting. The depths and widths of holes and incisions were measured using endodontic file under magnification. The speed of incisions was calculated and the required time for cutting was measured using sport clo
... Show MoreAbstract
In the present work, thermal diffusivity and heat capacity measurements have been investigated in temperature range between RT and 1473 K for different duplex stainless steel supplied by Outokumpu Stainless AB, Sweden. The purpose of this study is to get a reliable thermophysical data of these alloys and to study the effect of microstructure on the thermal diffusivity and heat capacity value. Results show the ferrite content in the duplex stainless steel increased with temperature at equilibrium state. On the other hand, ferrite content increased with increasing Cr/Ni ratio and there is no significant effect of ferrite content on the thermal diffusivity value at room temperature. Furthermore, the heat capacity of all sam
... Show MoreThe global oil market is one of the most important markets in the world and occupies especially for countries consuming and producing countries, and the status of understanding of the mechanism for determining prices in the market help to stand on many factors affecting oil demand and supply of oil and geopolitical factors, climate and alternative sources of energy .. etc. factors, and that the main objective of the research is to study the causes and results left behind by the oil price shocks in the world market, and the movement of these factors be through a cycle of energy that explain the strength of competition between these factors and their effects on prices, when demand increases evolution Large image leads to significan
... Show MoreBackground: The aims of this study were to evaluate the effect of implant site preparation in low-density bone using osseodensification method in terms of implant stability changes during the osseous healing period and peri-implant bone density using CBCT. Material and methods: This prospective observational clinical study included 24 patients who received 46 dental implants that were installed in low-density bone using the osseodensification method. CBCT was used to measure the bone density pre- and postoperatively and implant stability was measured using Periotest® immediately after implant insertion and then after 6 weeks and 12 weeks postoperatively. The data were analyzed using paired t-test and the probability value <0.05 was conside
... Show MoreThe Ground Penetrating Radar (GPR) is frequently used in pavement engineering
for road pavement inspection. The main objective of this work is to validate
nondestructive, quick and powerful measurements using GPR for assessment of subgrade
and asphalt /concrete conditions. In the present study, two different antennas
(250, 500 MHz) were used. The case studies are presented was carried in University
of Baghdad over about 100m of paved road. After data acquisition and radar grams
collection, they have been processed using RadExplorer V1.4 software
implementing different filters with the most effective ones (time zero adjustment and
DC removal) in addition to other interpretation tool parameters.
The interpretatio
The finite element method has been used in this paper to investigate the behavior of precast reinforced concrete dapped-ends beams (DEBs) numerically. A parametric investigation was performed on an experimental specimen tested by a previous researcher to show the effect of numerous parameters on the strength and behavior of RC dapped-end beams. Reinforcement details and steel arrangement, the influence of concrete compressive strength, the effect of inclined load, and the effect of support settlement on the strength of dapped-ends beams are examples of such parameters. The results revealed that the dapped-end reinforcement arrangement greatly affects the behavior of dapped end beam. The failure load decreases by 25% when
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