The term ‘photometry’ refers to the accurate determination of the apparent brightness of an astronomical object. Until roughly 1980, nearly all astronomical photometry was done by means of analog measurements of photographic plates, or by analog or digital (photon-counting) techniques with photomultipliers. These photometers produced brightness readings which were typically displayed on dials, plotted on strip charts or printed on strips of paper, and it was often quite practical to analyse these raw data with pencil, paper and a slide rule or table of logarithms. However, during the late 1970s electronic area detectors for astronomy became more advanced: first, for a brief period, television-type cameras were employed, but these were soon supplanted by CHARGECOUPLED DEVICES (CCDs), which remain overwhelmingly the detector of choice to the present day(Murdin 2001). The spiral galaxy NGC 3351 is chosen to study its photometric properties by using surface photometric techniques with griz-filters which is the main goal of this study. Observations are obtained from the seventh Sloan Digital Sky Survey (SDSS) Data Release (DR7)(Abazajian et al., 2009). All the images are corrected for bias and flat field by SDSS pipeline. We have analyzed the overall structure of the galaxy (a bulge, a disk, a bar), together with isophotal contour maps, luminosity profiles and performed a bulge/disk decomposition of the galaxy images, although we have estimated the disk position angle, ellipticity and inclination of the galaxy, it is favorable for investigating the brightness and color distributions over the disk of the galaxy. It is clear that the galaxy has a bright ring dominates the appearance of the circumnuclear, and a faint disk does not take on a spiral form , and from the position angle, ellipticity and B4 profiles of galaxy isophotes the values of the P.A. and ellipticity are fluctuated because of the bar and ring. The luminosity profile shows that the outer disk of this galaxy is of type II Freeman. Finally, the color indices of the NGC 3351 galaxy are characteristic of a normal spiral galaxy with some irregularity.
Plagiarism Detection Systems play an important role in revealing instances of a plagiarism act, especially in the educational sector with scientific documents and papers. The idea of plagiarism is that when any content is copied without permission or citation from the author. To detect such activities, it is necessary to have extensive information about plagiarism forms and classes. Thanks to the developed tools and methods it is possible to reveal many types of plagiarism. The development of the Information and Communication Technologies (ICT) and the availability of the online scientific documents lead to the ease of access to these documents. With the availability of many software text editors, plagiarism detections becomes a critical
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In this paper, a comparison between horizontal and vertical OFET of Poly (3-Hexylthiophene) (P3HT) as an active semiconductor layer (p-type) was studied by using two different gate insulators (ZrO2 and PVA). The electrical performance output (Id-Vd) and transfer (Id-Vg) characteristics were investigated using the gradual-channel approximation model. The device shows a typical output curve of a field-effect transistor (FET). The analysis of electrical characterization was performed in order to investigate the source-drain voltage (Vd) dependent current and the effects of gate dielectric on the electrical performance of the OFET. This work also considered the effects of the
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This paper is focusing on reducing the time for text processing operations by taking the advantage of enumerating each string using the multi hashing methodology. Text analysis is an important subject for any system that deals with strings (sequences of characters from an alphabet) and text processing (e.g., word-processor, text editor and other text manipulation systems). Many problems have been arisen when dealing with string operations which consist of an unfixed number of characters (e.g., the execution time); this due to the overhead embedded-operations (like, symbols matching and conversion operations). The execution time largely depends on the string characteristics; especially its length (i.e., the number of characters consisting
... Show MoreWaste is one of the most important problems affecting the city’s environment and its urban landscape, which results from the activities and activities of man and the natural environment. Its sources have varied between residential, commercial, industrial, medical and hazardous, and its spread in cities, on roads and on abandoned open lands, has led to significant negative effects and risks to human health and the environment.
Therefore, there were serious attempts to deal with waste and follow sequential steps that formed a waste management system such as (collection, sorting, transport, then treatment and disposal). Preventing and reducing waste, then recycling and recovering by composting or burning, and ending with bu
... Show MoreAwsaj (Lycium barbarum) is a plant belong to family Solanaceae serves as a good source of bioactive compounds like phytosterols which have many important biological activity. Literature survey available so far revealed that there was no studies about Iraqi wild Awsaj phytosterols especially B-sitosterol, there for the objective of this study was to examine the efficiency of ultrasound assisted extraction (probe and bath) as compared to the conventional (Soxhlet) extraction method for extraction of phytosterols especially B-sitosterol from fruits, leaves, stems and roots of Iraqi wild Awsaj plant. This goal was achieved by comparing the extraction mass yield, also by a quick and easy approach for identification and quantification of bioac
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The effect of thickness variation on some physical properties of hematite α-Fe2O3 thin films was investigated. An Fe2O3 bulk in the form of pellet was prepared by cold pressing of Fe2O3 powder with subsequent sintering at 800 . Thin films with various thicknesses were obtained on glass substrates by pulsed laser deposition technique. The films properties were characterized by XRD, and FT-IR. The deposited iron oxide thin films showed a single hematite phase with polycrystalline rhombohedral crystal structure .The thickness of films were estimated by using spectrometer to be (185-232) nm. Using Debye Scherrerś formula, the average grain size for the samples was found to be (18-32) nm. Atomic force microscopy indicated that the films had
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... Show MoreEight different Dichloro(bis{2-[1-(4-R-phenyl)-1H-1,2,3-triazol-4-yl-κN3]pyridine-κN})iron(II) compounds, 2–9, have been synthesised and characterised, where group R=CH3 (L2), OCH3 (L3), COOH (L4), F (L5), Cl (L6), CN (L7), H (L8) and CF3 (L9). The single crystal X-ray structure was determined for the L3 which was complemented with Density Functional Theory calculations for all complexes. The structure exhibits a distorted octahedral geometry, with the two triazole ligands coordinated to the iron centre positioned in the equatorial plane and the two chloro atoms in the axial positions. The values of the FeII/III redox couple, observed at ca. −0.3 V versus Fc/ Fc+ for complexes 2–9, varied over a very small potential range of 0.05 V.
... Show MoreIn this study, we report a statistical study for the relationship between coronal mass ejections (CMEs) and sunspot number (SSN) that were registered during the period 2008-2017 for the solar cycle 24. SSN was extracted from Sunspot Index and Long-term Solar Observations (SILSO), while CMEs number from observations made by the Large Angle and Spectrometric Coronagraph (LASCO) on board the Solar and Heliospheric Observatory mission (SOHO). The present period was adopted to conduct the investigation and obtain the mutual correlation between SSN and CMEs. The relationship between CME, the speed of halo CME, and partial halo CMEs for solar cycle 24 were studied. The analysis of results indicated that the average speed of halo CMEs is almost
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