In this work a Nd:YVO4 thin disc laser setup is designed and fabricated. The disk laser system
is designed to be compact. The laser crystal was pumped by a 808 nm diode laser. The effect of input
current and pulse frequency on the output energy at pulse operation mode, and the effect of the input
current on the output power at CW mode operation are tested. At the pulsed mode, the output energy
increased linearly with the input current and decreased with pulse frequency. The threshold current
increased with increasing pulse frequency increasing. The maximum output energy from the thin disc
laser was 0.98 μJ at 1.3 kHz frequency, with 0.49A. A minimum threshold current for CW mode of
operation. The maximum output power from the disc laser was 22 mW.
Observed mosques with the advent of Islam under the auspices of care being the houses of God Almighty, and I like parts of the ground to him, the center of radiation spiritual, intellectual and ideological in the lives of Muslims, was the most important cultural and architectural evidence built by Muslims voicing their deep faith and serenity Aqidthm.valmsadjad better reflecting the reality of communication between the person and his Lord, because he is the most important building of permanence and survival, making it imperative designed the best visual forms both externally and internally.Mosques have been characterized in the United Arab Emirates distinct characteristics in terms of building elements of construction in general, and the
... Show MoreIn this paper, the deterministic and the stochastic models are proposed to study the interaction of the Coronavirus (COVID-19) with host cells inside the human body. In the deterministic model, the value of the basic reproduction number determines the persistence or extinction of the COVID-19. If , one infected cell will transmit the virus to less than one cell, as a result, the person carrying the Coronavirus will get rid of the disease .If the infected cell will be able to infect all cells that contain ACE receptors. The stochastic model proves that if are sufficiently large then maybe give us ultimate disease extinction although , and this facts also proved by computer simulation.
Background Epilepsy is one of the most widespread neurological illnesses in the world with a prevalence rate of 2.8–19.5 per 1000 of the general population, and it is more prevalent in childhood. The understanding of the teachers about epilepsy has a significant impact on the academic performance and social skills of schoolchildren with epilepsy. Aim of Study This study aimed to assess teachers’ knowledge, attitude, and practice regarding epilepsy in schoolchildren and the association of certain studied variables with the level of schoolteachers’ knowledge, attitude, and practice. Subjects and Methods This was a cross-sectional study that included 402 participants and was conducted in Al-Rusafa/Baghdad during the period from November
... Show MoreThe current research addresses the psychological disobedience in general and disobedience in post-modernism arts in specific. The research problem is summarized by the following question: does disobedience have representations in the graffiti art? The research objective is to identify disobedience and its representations in the graffiti. The research limits are set and the terms used are identified. As for the theoretical framework, it consists of three sections: the first: the psychological disobedience, whereas the second: disobedience in post-modernism arts. The third section addresses graffiti art. Then come the research procedures followed by the results, conclusions, recommendations, and suggestions. The two researchers arrived at
... Show MoreThe main objective of the audit is The asset is maintained and operated efficiently and is done through to detect fraud and errors in the financial statements and to verify the accuracy and accuracy of the information contained therein and to give a neutral technical opinion on the basis of that, thus the auditor has a professional responsibility in achieving this goal, and that the effects of issuing a wrong opinion works on The loading of the beneficiaries is significant damage, And therefore the presence of any error or bias of the auditor when taking personal judgments in relation to the determination of the relative importance and the selection of audit samples and determine the adequacy and validity of evidence and implemen
... Show MoreZinc oxide (ZnO) nanostructures were synthesized through the hydrothermal method at various conditions growth times (6,7 and 8 hrs.) and a growth temperature (70, 90, and 100 ºC). The prepared ZnO nanostructure samples were described using scanning electron microscopy (SEM) and X-ray diffractometer to distinguish their surface morphologies and crystal structures. The ZnO samples were confirmed to have the same crystal type, with different densities and dimensions (diameter and length). The obtained ZnO nanostructures were used to manufacture gas sensors for NO2 gas detection. Sensing characteristics for the fabricated sensor to NO2 gas were examined at different operating temperatures (180, 200, 220, and 240) ºC with a low gas concentrati
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The aim of this research is to identify the Andalusia poet Abu Izac Al-Zauali , whose most of his poetry and biography had been lost, as well as many Andalusia poets. So this research is hoped to be the first step to shed the light on the poet’s life and poetry and to document his poetry as other writers do. It is also hoped that this research would pave the way , God willing , to the steps of finding more references about this poet .
Key Words: (Al-Zauali, Cordoba, Al-Ruaini choices, Andalusia Poetry , Almuahdi Era).
Thin films of pure polycarbonate (PC) with anthracene doping PC films for different doping ratios (10, 20, 30, 40, 50 and 60 ml) were prepared by using a casting method. The influence of anthracene doping ratio on photo-fries rearrangement of polycarbonate was systematic investigated. Furthermore, pure PC and anthracene doping PC films were irradiated via UV light at a wavelength (254 nm) for different periods (5, 240, 288, and 360 hrs). The photo-fries rearrangement occurring in pure PC and anthracene doping PC films were monitored using UV and FTIR spectroscopies. The photo-fries rearrangement leads to scission the carbonate linkage and formation phenylsalicylate and dihydroxybenzophenes. The result of the UV spectrum confirms disappea
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