The influence of 5-10 kHz audio frequency on the power dissipation in ac discharge of argon gas was studied experimentally, at pressures 50-80 mTorr and electrodes separation 10 cm (pd range 0.5-0.8 Torr.
cm). The measurements have shown that the discharge behavior in the ac circuit is equivalent to a series RC circuit. It is observed that the variation curve of discharge power P with the frequency f is approximately has a Gaussian shape. It is also observed that the curve of Pm- pd is the inverse of Paschen curve, where Pm is the maximum power in the frequency range. The time of breakdown is estimated from the curve of P- f.
In this study; a three-dimensional model was created to simulate groundwater in Al-Haydariyah area of the governorate of Al-Najaf. A solid model was created to utilize the cross sections of 25 boreholes in the research region, and it was made out of two layers: sand and clay. The steady-state calibration was employed in six observation wells to calibrate the model and establish the hydraulic conductivity, which was 17.49 m/d for sand and 1.042 m/d for clay, with a recharge rate of 0.00007 m/day. The wells in the research region were reallocated with a distance of 1500 m between each well, resulting in 140 wells evenly distributed throughout the study area and with a discharge of 5 l/s, and the scenarios were run for 1000
... Show Morebased on the importance of public relations in companies, I will discussed the issue of public relations and its role in marketing national products, given what these companies represent of great importance in terms of providing products and services to large segments of Iraqi society, which necessitated the need to search and investigate the role and importance of activities that Provides public relations in Iraqi companies in all categories( public, private and mixed).
the study tables and theirinterpretations, results and recommendations, and the studyreachedseveralresults, including the positive and the negative, the positive including the success in marketing the products by the number of companies in the Fairswhere the level of
This study was undertaken to prepare Nano zinc oxide (ZnO) by precipitation and microemulsion methods. Scanning electron microscopy (SEM), X-ray diffraction (XRD), FTIR spectrometry, atomic force microscopy (AFM), and Brunauer Emmett Teller (BET) surface area were the techniques employed for the preparation. The particle size of prepared nano ZnO was 69.15nm and 88.49nm for precipitation and microemulsion methods, respectively, which corresponded to the BET surface area 20.028 and 16.369m2/g respectively. The activity of prepared nano ZnO as a photocatalyst was estimated by the removal of ampicillin (Amp) under visible light. This study, therefore, examined the effect of pH in the range of 5-11, initial concen
... Show MoreBackground: Recently with improvement of dental implantology science, osseointegrated implants show a considerable durability, however; failures are not completely avoidable. Matrix metalloproteinase-2 (MMP-2) expression is disturbed in many pathological conditions such as peri-implantitis and periodontitis. This study was carried out to investigate the tissue expression of MMP-2 in the extracellular matrix of osseointegrated and diseased implants. Subjects and methods: Gingival biopsies were collected from six patients having osseointegrated or working implants and twenty with diseased or non osseointegrated implants and (6) controls having no implants. In situ hybridization technique was used to analyze the changes in immunoreactivity of
... Show MoreThe researchers aim of this research to analyze the reality of educational services in the city of Ramadi in order to reveal the efficiency of the spatial distribution of schools at the level of residential neighborhoods and the requirements of the population, based on the standards and indicators for this service.
The research problem related to the educational function of the city of Ramadi was formulated by asking about the efficiency of the spatial distribution of educational services and whether there is a balance in the distribution of schools to residential neighborhoods in a way that meets the requirements of the population, and in order to answer the research problem, the research hypothesis was formulated that there is
... Show MoreThe current research aims to assess the Brief Book of the Modern and Contemporary History of Asia from the perspective of the students in the Department of History, University of Baghdad. The study is carried out in Iraq and the research group has included students of the Department of History in the College of Education--Ibn Rushd and the College of Education for Women- University of Baghdad. The chosen sample of the assigned research consisted of (72) students from third stage in the Department of History, which equals (0.38%) of the total group members amounted (188) female and male students representing (40) students from the College of Education--Ibn Rushd, and 32 students from
... Show MoreThis research cancellations in life insurance policies and their impact on the solvency of the insurance companies (Applied Research in the Iraqi general insurance company), The study was descriptive approach in identifying and addressing variables which consists of {cancellations in life insurance} independent variable, the financial solvency of insurance companies as the dependent variable, and for the purpose of achieving the objectives of the research were formulated one hypothesis has been tested in the Iraqi insurance company, the researcher used the financial statements in the collection data needed for the study and information . The research found a number of conclusions highlighted that inflation, as well as economic variables
... 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
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