The effect of thermal treatment on optical constants of pure PMMA and with addition (15 and 35) ml of coumarin at different temperatures (100, 110 and 120) C0 for 1 hour were investigated. Cast method used to prepares films of pure PMMA and PMMA with (15 and 35) of coumarin. UV/VIS spectrometer technique used to measure the absorption spectra for these films. The optical constant (absorption spectra and absorption coefficient) don’t changes after applied temperatures in pure PMMA film but the optical constant (absorption spectra and absorption coefficient) in PMMA with (15 and 35) ml of coumarin increased with applied temperatures. The optical energy gap of pure PMMA and PMMA with (15 and 35) ml of coumarin slightly decreased after applied temperature up to 1200 C.
In this work the effect of annealing temperature on the structure and the electrical properties of Bi thin films was studied, the Bi films were deposited on glass substrates at room temperature by thermal evaporation technique with thickness (0.4 µm) and rate of deposition equal to 6.66Å/sec, all samples are annealed in a vacuum for one hour. The X-ray diffraction analysis shows that the prepared samples are polycrystalline and it exhibits hexagonal structure. The electrical properties of these films were studied with different annealing temperatures, the d.c conductivity for films decreases from 16.42 ? 10-2 at 343K to 10.11?10-2 (?.cm)-1 at 363K. The electrical activation energies Ea1 and Ea2 increase from 0.031 to 0.049eV and
... Show MoreThe experiment was carried out in College of Agricultural Engineering Sciences, University of Baghdad during November 1, 2019 to June 1, 2020. The experiment was designed according to a randomized complete block design. Each block contained 18 experimental units that included the three study factors. The first factor interaction between two inoculum densities and application methods, three levels control, treatment of seeds inoculation with 5g plant and treatment of seedlings inoculation whith 30g plant . The second factor was three -1 -1concentrations of spraying of kinetin 0, 75 and 150 mg L , and third factor include two levels of organic manure) and addition of fertilizer 2% of -1 the weight of the soil (O2). The results showed a signif
... Show MoreThe enrollment of students in the university represents a new stage in their life that differ from the previous educational stages that student has previously established. It should be noted that students with special needs at the University of Baghdad are not large numbers. It appears that these students have an excel role in their colleges most often, That is, the handicap was not a barrier to their scientific progress, but rather an incentive for them to excel. The most important conclusion reached by the researcher is that the University of Baghdad had no role in caring for people with special needs and caring for them financially, socially, psychologically, healthily and economically, they need to pay attention to them and take care
... Show MoreThe research aims to show the role or extent of the impact of financing in its various forms on the municipal performance before and after the financial deficit through relying on the analytical research methodology of the research community represented by the Directorate General of Municipalities and the Directorate of Maysan municipalities as a sample of research (13) municipal institutions for a period of (8) years, Considering the completion of the final accounts of these years, which provides the necessary data for the study, in addition to the variation in the quality and amounts of grants allocated to municipal institutions during these years, which gives a clearer and more comprehensive picture of the reality of allocatio
... Show MoreShell-and-double concentric tube heat exchanger is one of the new designs that enhance the heat transfer process. Entransy dissipation is a recent development that incorporates thermodynamics in the design and optimization of heat exchangers. In this paper the concept of entransy dissipation is related to the shell-and-double concentric tube heat exchanger for the first time, where the experiments were conducted using hot oil with temperature of 80, 100 and 120°C, flow rate of cold water was 0.667, 1, and 1.334 kg/m3 respectively and the temperature of inlet cold water was 20°C. The entransy dissipation rate due to heat transfer and to fluid friction or pressure drop was studied.
Abstract: Despite the distinct features of the continuous wave (CW) Terahertz (THz) emitter using photomixing technique, it suffers from the relatively low radiation output power. Therefore, one of effective ways to improve the photomixer emitter performance was using nanodimensions electrodes inside the optical active region of the device. Due to the nanodimension sizes and good electrical conductivity of silver nanowires (Ag-NWs), they have been exploited as THz emitter electrodes. The excited surface plasmon polariton waves (SPPs) on the surface of nanowire enhances the incident excitation signal. Therefore, the photomixer based Ag-NW compared to conventional one significantly exhibits higher THz output signal. In thi
... Show MoreThis study aimed to find out the impact of work-life balance on employee satisfaction in five-star hotels in Amman, Jordan based on a descriptive analytical approach. The questionnaire of the survey was designed and distributed to a sample of participants in order to collect the necessary data for this study and they were analyzed later through the SPSS V22 program. The study population was the hotel sector in Jordan, while the study sample included the five-star hotels in the capital, Amman, and the sampling unit included the employees of the middle and lower levels of management in the five-star hotels in Amman. The study showed a number of results, including the existence of a good level of work-life balance by employees in top manage-me
... 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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