Bragg Reflectors consist of periodic dielectric layers having an optical path length of quarter wavelength for each layer giving them important properties and makes them suitable for optoelectronics applications. The reflectivity can be increased by increasing the number of layers of the mirror to get the required value. For example for an 8 layers Bragg mirror (two layers for each dielectric pair), the contrast of the refractive index has to be equal to 0.275 for reaching reflectivity > 99%. Doubling the number of layers results in a reflectivity of 99.99%. The high reflectivity is purely caused by multiple-interference effects. It can be analyzed by using different matrix methods such as the transfer matrix method (TMM) which is the simplest method to study the characteristic of devices with different alternating layers.
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The research aimed to study the decision-making of the administrative bodies of sports clubs participating in the Iraqi Football Premier League for the 2022-2023 season. The researchers used the descriptive approach (survey study) to suit the nature of the research. The research community is represented by members of the administrative bodies of the sports clubs participating in the Iraqi Premier Football League for the 2022-2023 season, who number (177) members of the administrative body. The researchers used the questionnaire to collect the necessary data to achieve the goal of researching The method of applying a questionnaire aimed to identify the decision-making of the administrative bodies of sports clubs. The most important r
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This research is based on monitoring the local and environmental technologies in the design of the temporary hotel units (nomadic tents) in the desert in the south of Jordan in order to air condition them in summer and winter, maintaining the Jordanian identity, that they are presented with the form and technologies of the age in order to get to the universality.
The research adopted the descriptive analytical method and the researcher conducted the analysis of SWOT specified for the analysis of the positive and negative aspects in the design of the temporary hotel units and comparing them with the case studies available in the chosen research area "the Jordanian golden triangle", through the elements of the case under study. The res
The compound [K1] was synthesized from the reaction of dichloromethane with linear alkyl benzene (Lab9) using ethanol as a solvent, and from(chloro methyl)-4-nonylbenzene) [K1] it was possible to synthesize the compound Z(4-(nonan-3-yl)phenyl) methane amine) [K2] containing the amine group by synthesized from [K2] reaction with appropriate phenolic aldehydes and using Ethanol as a solvent in the preparation of vinyl chloride4-(((4-nonylbenzyl)imino)methyl)phenol-4-(((4-nonylbenzyl)imino methyl)benzene-1,3diol) [K3-K4] bases has been used. Preparation of a number of Phenolic polymers4-(2- hydroxy-3.5-dimethylbenzyl)-2-methyl-6-(((4-4-(2hyroxy-3, 5-dimethylbenzyl)-2-methyl-6(((4 nonylbenzyl) imino) methyl) benzene-phenolnonylbenzyl) imino) me
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Abstract
Coronavirus has affected many people around the world and caused an increase in the number of hospitalized patients and deaths. The prediction factor may help the physician to classify whether the patient needs more medical attention to decrease mortality and worsening of symptoms. We aimed to study the possible relationship between C reactive protein level and the severity of symptoms and its effect on the prognosis of the disease. And determine patients who require closer respiratory monitoring and more aggressive supportive therapies to avoid poor prognosis. The data was gathered using medical record data, the patient's medical history, and the onset of symptoms, as well as a blood sample to test the
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