The paper presents an overview of theoretical aspects of small radio telescope antenna parameters. The basic parameters include antenna beamwidth, antenna gain, aperture efficiency, and antenna temperature. These parameters should be carefully studied since they have vital effects on astronomical radio observations. The simulations of antenna parameters were carried out to assess the capability and the efficiency of small radio telescopes to observe a point source at a specific frequency. Two-dimensional numerical simulations of a uniform circular aperture antenna are implemented at different radii. The small diameter values are chosen to be varied between (1-10) m. This study focuses on a small radio telescope with a diameter of 3 m since this telescope is very common in the world. The simulated results of this study illustrated that the power pattern of a 3 m antenna has a half-power beamwidth of approximately 5 degrees. Also, the maximum peak antenna temperature is estimated to be more than 3000 K. All of these results were in good agreement with observations of the neutral hydrogen spectral line at the frequency of 1.42 GHz using a small radio telescope.
Multilevel models are among the most important models widely used in the application and analysis of data that are characterized by the fact that observations take a hierarchical form, In our research we examined the multilevel logistic regression model (intercept random and slope random model) , here the importance of the research highlights that the usual regression models calculate the total variance of the model and its inability to read variance and variations between levels ,however in the case of multi-level regression models, the calculation of the total variance is inaccurate and therefore these models calculate the variations for each level of the model, Where the research aims to estimate the parameters of this m
... Show MoreAcrylic polymer/cement nanocomposites in dark and light colors have been developed for coating floors and swimming pools. This work aims to emphasize the effect of cement filling on the mechanical parameters, thermal stability, and wettability of acrylic polymer. The preparation was carried out using the casting method from acrylic polymer coating solution, which was added to cement nanoparticles (65 nm) with weight concentrations of (0, 1, 2, 4, and 8 wt%) to achieve high-quality specifications and good adhesion. Maximum impact strength and Hardness shore A were observed at cement ratios of 2 wt% and 4 wt%, respectively. Changing the filling ratio has a significant effect on the strain of the nanocomposites. The contact angle was i
... Show MoreThere is currently a significantly larger concentration of toxins in our environment than there was in the past. This is mostly attributable to the expansion of modern industry. This investigation was conducted in order to investigate various haematological and biochemical changes in order to determine the effects of Cd on the liver and kidney. Because of its long biological half-life, it is considered hazardous to human health. The effect of sub-lethal doses (40, 80 and 120 mg\Kg) of Cadmium (Cd) on male mice were evaluated for 4 weeks, and analysis was done to estimate their biochemical parameters and antioxidant enzymes. The results showed that Cd-treated mice had considerably lower packed cell volume, red blood cells, and haemoglobin. W
... Show MoreIn this work, spinel ferrites (NiCoFe2O4) were prepared as thin films by dc reactive dual-magnetron co-sputtering technique. Effects of some operation parameters, such as inter-electrode distance, and preparation conditions such as mixing ratio of argon and oxygen in the gas mixture, on the structural and spectroscopic characteristics of the prepared samples were studied. For samples prepared at inter-electrode distance of 5 cm, only one functional group of OH- was observed in the FTIR spectra as all bands belonging to the metal-oxygen vibration were observed. Similarly, the XRD results showed that decreasing the pressure of oxygen in the gas mixture lead to grow more crystal planes in the samples prepare
... Show MoreThis research was conduct to evaluate the cytotoxic effect of exotoxin A (ETA) produced by Pseudomonas aeruginosa on mice in comparison with (phosphate buffer saline (PBS) as a negative control. The effect of the toxin was measured by employing the cytogenetic analysis which included (the mitotic index (MI), chromosomal aberrations (CAs), micronucleus (MN) and sperm abnormalities) parameters. In order to specify the cytotoxic effect of the toxin, three doses of ETA (125, 250 and 500 ng/ml) were used. Results showed that ETA was found to cause a significant decrease in mitotic index (MI) percentage, while significant increase in micronucleus (MN), chromosomal aberrations (CAs) and sperm abnormalities parameters in compression with control wa
... Show MoreIncremental Sheet Metal Forming (ISMF) is a modern sheet metal forming technology which offers the possibility of manufacturing 3D complex parts of thin sheet metals using the CNC milling machine. The surface quality is a very important aspect in any manufacturing process. Therefore, this study focuses on the resultant residual stresses by forming parameters, namely; (tool shape, step over, feed rate, and slope angle) using Taguchi method for the products formed by single point incremental forming process (SPIF). For evaluating the surface quality, practical experiments to produce pyramid like shape have been implemented on aluminum sheets (AA1050) for thickness (0.9) mm. Three types of tool shape used in this work, the spherical tool ga
... Show MoreIn this study, the possible protective effects of daidzein on ifosfamide-induced neurotoxicity in male rats were examined by the determination of changes in selected oxidant–antioxidant markers of male rats’ brain tissue.
Twenty-eight (28) apparently-healthy Wistar male rats weighing (120-150gm) allocated into 4 groups (n=7) were used in this study. Rats orally-administered 1% tween 20 dissolved in distilled water/Control (Group I); rats were orally-administered daidzein suspension (100mg/kg) for 7 days (Group II); rats intraperitoneally-injected with a single dose of ifosfamide (500 mg/kg) (Group III); rats orally-administered for 7 days with the daidzein (100mg/
... Show MoreThe acoustic efforts of the glass were found in the meanings mixed with other linguistic, grammatical and morphological issues, as the glass was not allocated to the detective or separate chapters in the meanings. The glass-walled in the audio lesson according to the doctrine of the optical, has stated so in several places of its meaning. Glass is interested in mentioning the strong qualities that have a great impact in the chorus and replacements such as loudness, dishes, arrogance, whistling, repetition, and richness. Glass was concerned with the phenomenon of diphtheria great care, and explained its purpose of seeking lightness and ease of pronunciation, and Siboe agreed in its origins and issues, and the glass used three criteria in
... Show MoreAbstract
The Research "Surah At-Talaq between Commentators and Jurists" is summarized in the objectives of the Surah, clarifying the meanings of the verses of the rulings contained therein by mentioning the statements of the commentators, with mentioning the most acceptable of those meanings when a difference arises, explanation of the provisions of the Surah, with a statement of sayings of the four religious schools of Islamic jurisprudence, in summary, due to the narrowness of the place, and the most acceptable of them.
The research addresses (9) topics, which are: the objectives of Surah At-Talaq, prohibition of divorce during menstruation, testifying retract and divorce, irrevocably divo
... Show MoreBackground: Saliva is one of the most important etiological host factors in relation to dental caries. It affects the carious process by its organic and inorganic constituents; in addition to its physiological functions as (flow rate, pH and buffer capacity). The aims of this study were to determine the concentrations of major elements (calcium and phosphorus) and trace elements (ferrous iron, nickel, chromium and aluminum) in saliva among a group of adolescent girls, and to explore the relation of these elements, flow rate and pH with dental caries. Material & Methods: The study group consisted of 25 girls with an age of 13-15 years old. Dental caries was diagnosed by both clinical and radiographical examinations following the criteria of
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