Because of Cadmium selenide quantum dots (CdSe quantum dots) has a tuning energy gap in the visible light range, therefore; it is provided a simple theoretical model for the absorption coefficient of CdSe quantum dots, where the absorption coefficient determines the extent to which the light of a material can penetrate a specific wavelength before it is absorbed. CdSe quantum dots have an energy gap can be controlled through two effects: the temperature and the dot size of them. It is found that; there is an absorption threshold for each directed wavelength, where CdSe quantum dots begin to absorb the visible spectrum at a size of 1.4 nm at room temperature for a directed wavelength 300 nm. It has been observed that; when the wavelength is increasing its absorption threshold is increased. For wavelengths (400, 500, 600) nm, the absorption thresholds for each quantum sizes are (1.8, 2.2. 3.2)nm respectively. On the other hand, a rising of the temperature led to reduces the absorption coefficient value, that at 400 K for all quantum sizes, the absorption coefficient increases >2000cm−1(According to the directed wavelength) than it is at 0 K. CdSe quantum dots can be considered as one of the most promising materials because it has a tuning gap for the visible wavelengthsfor different applications, such as light-emitting diodes in different colors of the visible spectrum. It is found that; there is a good agreement between our theoretical calculations and experimental results.
In a quick reading of the character of Camille Ben Ziad al-Nekha al-Kufi al-Taabi, one of the most sincere companions of Imam Ali (peace be upon him), he enjoyed great status and status because he was one of the people of his people who lived alongside Imam Ali (peace be upon him) since his tribe migrated from Yemen to Kufa To this end, he became loyal during the reign of Imam Ali (peace be upon him), who is also a member of the delegation coming from Kufa to protest against the actions of the Wali of Kufa during the reign of Caliph Uthman ibn Affan. After the death of Caliph Uthman bin Affan, (Peace and blessings of Allaah be upon him) (Duaa kamil), one of the most famous and important supplications in Islamic history, and each one of u
... Show MoreArabic calligraphy has a special status as one of the most important oriental arts, which has been enhanced by the Islamic value. The Arabic fonts have been diverse in their classification into soft lines such as Diwani, thuluth and patch lines and others, and geometrical lines such as Kufic lines and their various types. The contemporary artist was also able to adapt the Arabic calligraphy of all kinds in the construction of the painting or line formations, especially after the development of the artistic digital techniques and computer software. Here comes the role of the industrial designer as being more in touch with the practical, technical and productive life, which requires great care in adapting the line formations of the Arabic
... Show MoreThe problem of the study is to monitor the content presented in the Iraqi satellite channels to identify the nature of the ideas contained in these ads and to identify the values carried by the creative strategies and ad campaigns that use. Where the satellite is one of the most important technological developments in the field of communications in the nineties and the ads in various forms and functions one of the contents provided by satellite channels where these channels are keen to direct their messages in particular and communication, in general, to address a certain audience and convince and influence in order to achieve certain purposes of the source Or the body from which it originates, especially those that result in an in
... Show MoreThroughout history, artists have played many important roles in society.
Generally speaking, the role of the artist is defined by the society he is part of.
Indeed, there are as many ideas as to the role of the artist and, ultimately the purpose
of art in society, as there are types of art. This is, as a matter of fact, neither a new
question- the dialogue has been present within art for centuries- nor probably one
that will ever fully be answered.
Tom Stoppard came to prominence in the mid-sixties, when art and politics
were closely linked, and theatre sought to change the world. Stoppard would have
none of that: his work has no overt message, no political program. In fact,
... Show Moreforty-six patients with asthma were tested for the scrum levels of total sialic and diffrental the results reveled a significant increased in the scra of asthmatic patients
A three species food web model involving a stage structure and cannibalism in the top predator species is proposed and studied. It is assumed that the prey species growth logistically in the absence of predator and the predation process occurred according to theLotka-Volterra functional response. The existence, uniqueness and bounded-ness of the solution of the model are investigated. The local and global stability conditions of all possible equilibrium points are established.The persistence conditions of the model are also determined. The local bifurcation near each of the equilibrium points is analyzed. The global dynamics of the model is investigated numerically and compared with the obtained analytical results. It is observed that the p
... Show Morechronic obstructive pulmonary disease (COPD) is a common respiratory disease with episodes of exacerbation. Variable factors including infectious pathogen can predispose for this exacerbation. The aim of this study is to evaluate the role of intestinal protozoa in COPD exacerbation. A total of 56 patients with COPD were included in this study. Patients were categorized into two groups based on the frequency of exacerbation during the last 6 months: those with ≤1 exacerbation (32 patients) and those with ≥2 exacerbations (24 patients). Stool specimens from each patient were collected two times (one week interval) examined for intestinal parasite. In univariate analysis, rural residence and parasitic infection were more common among patie
... Show MoreBackground: Neonatal macrosomia is defined as a birth weight of more than 4000 g. Significant maternal and neonatal complications can result from the birth of macrosomic infants like hypoglycemia and birth injuries.Objectives: To determine the frequency of hypoglycemia in neonates with macrosomia in Amarah, IraqMethods: The study involved 146 macrosomic newborn neonates delivered in 2 maternity hospitals in Amarah, Iraq during a period from June 2011 to June 2014.Results: Hypoglycemia was observed in 16% of neonates affected by macrosomia. Maternal diabetes was the most common cause of fetal macrosomia (28%).Our results were compared with those from other parts of the world.Conclusion Macrosomia is associated with increase rate ofneonata
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