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.
This study aims to know the role of strategic leadership to achieving competitiveness in industrial establishments by identifying the respondents’ perceptions about the level of availability of dimensions of leadership strategies (creativity and innovation, risk tolerance, available opportunities) in Bashir Al-Siksek & Partners Company for the manufacture of sanitary and plastic ware in Gaza strip
To achieve this, a questionnaire was developed and distributed to a sample of managers, auditors, accountants, and administrative employees in the study sample company. The questionnaire tool was distributed to 60 employees and employees, of which (52) were retrieved, or 86.6%, and (8) were excluded for la
... Show MoreFrançois Mauriac’s novel The Desert of Love (1949) puts the reader before an experienced sociologist who is skillfully able to analyze the most mysterious human emotions and feelings. The writer's starting point is that people are similar in feelings but different in behavior. He severely criticized the aristocratic class and uncovered its defects and faults.
The novelist presents Courege's family as an example of the aristocratic class. It is a family torn by hatred, selfishness and disagreements due to absence of intimacy and love. This poisoned environment pushes the father and his son, Raymond, to search away for emotional ventures and banned relations
... Show MoreOriganum majorana (Majorana hortensis), an evergreen herbaceous plant belonging to the Lamiaceae family, has been well known for being used for gastrointestinal, cardiac, respiratory, rheumatologic and many other illnesses, but in wounds management hasn’t been qualified scientifically yet. The goal of the study was to evaluate the wound healing properties of sterols in n-hexane and phenols in ethyl acetate extract fractions of the Iraqi Origanum majorana L aerial parts by contrasting their wound healing abilities with those of commercially available MEBO ointment in a rat excised wound repair model. At various periods, the size of the wounds was measured and skin tissue samples were taken for histopathology. When compared to positive and
... Show MoreAt the time when many important political events and evolutions took place, the cinema has been pretty active, and witnessed the historical events before and after the two world wars and the cold war. During the first half of the 20th century, the cinema had great interest from the major countries and their politicians, as well as the commercial turnout of large companies to invest in that field for the profits. In the beginning of the 20th century, the major powers like the Soviet Union, the United States, Germany, Italy, England, and France started to compete in the development of their film industry and the investment of the new medium and the transformation of some famous works of fiction into films that perpetuate their cultur
... Show MoreIn the name of of Allah the Merciful
Research Summary
This rule is one of the common rules between the sciences of the principles of jurisprudence and the jurisprudence rules. It is originally a fundamental rule because it relates to one of the topics of the science of the principles of jurisprudence, which is ijtihad. The ruling on reversing his ijtihad is permissible or not (1), and for this reason Ibn Al-Subki titled it in his book Al-Ishbah wa Al-Nazaer by saying: “What invalidates the judge’s judgment and what does not invalidate it.” ([2]).
The importance of this rule comes from the need for it by the judge, the mufti and the imitator, for the judge needs it to know the matters in which the ruling base
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