In this research, the electrical characteristics of glow discharge plasma were studied. Glow discharge plasma generated in a home-made DC magnetron sputtering system, and a DC-power supply of high voltage as input to the discharge electrodes were both utilized. The distance between two electrodes is 4cm. The gas used to produce plasma is argon gas which flows inside the chamber at a rate of 40 sccm. The influence of work function for different target materials (gold, copper, and silver), - 5cm in diameter and around 1mm thickness - different working pressures, and different applied voltages on electrical characteristics (discharge current, discharge potential, and Paschen’s curve) were studied. The results showed that the discharge current and potential increase by increasing the applied voltage ranging between 300-700 V. Discharge current increased as working pressure increased in the beginning, and then semi-stabilized (slight increase) starting from 1×100 mbar, while discharge potential decreased at the beginning as working pressure increased and then semi-stabilized at the same point at which discharge current stabilized. The Paschen’s curves were compared with each other. It was concluded that the lower breakdown voltage was associated with lower work function of the (Au, Cu, and Ag) cathode material. Breakdown voltages were (395, 398, and 420) for Ag, Cu and Au respectively.
The aim of this research is to design and construct a semiconductor laser range finder
operating in the near infrared range for ranging and designation. The main part of the range finder is the
transmitter which is a semiconductor laser type GaAs of 0.904 mm wavelength with a beam expander,
and the receiver with its collecting optics. The characteristics of transmitter pulse width were 200ns and
threshold current 10 Amp. and maximum operating current 38 Amp. The repetition rate was set at 660 Hz
and maximum output power about 1 watt. The divergence of the beam was 0.268o. A special computer
code was used for optimum optical design and laser spot size analysis and for calculation of atmosphere
attenuation.
In this work, the surface of the telescope’s mirror is cleaned using an atmospheric-pressure radio frequency plasma jet (APRFPJ), which is generated by Argon gas between two coaxial metal electrodes. The RF power supply is set to 2 MHz frequencies with three different power levels: 20, 50, and 80 W. Carbon, that has adhered to the surface, can be effectively removed using the plasma cleaning technique, which also modifies any residual bonds. The cleaned surface was clearly distinguished using an optical emission spectroscopy (OES) technique and a water contact angle (WCA) analyzer for the activation property on their surfaces. The sample showed a super hydrophilic surface at an angle of 1° after 2.5 minutes of plasma tre
... Show MoreHuman health can be negatively impacted by exposure to loud noise, which can harm the auditory system. Traffic noise is the leading cause of noise pollution. This paper studies the problem of noise pollution on the roads in Baghdad, Iraq. Due to the increase in vehicle numbers and road network modifications in Baghdad, noise levels became a serious topic to be studied. The aim of the paper was thus to study traffic noise levels and the effect of the traffic stream on noise levels and to formulate a prediction model that identified the guidelines used for designing or developing future roads in the city. Then, the noise levels were measured based on five variables: the functional classification of roads, traffic flow, vehicle speed,
... Show MoreInvestigating the thermal and electrical gains and efficiencies influence the designed photovoltaic thermal hybrid collector (PVT) under different weather conditions. The designed system was manufactured by attaching a fabricated cooling system made of serpentine tubes to a single PV panel and connecting it to an automatic controlling system for measuring, monitoring, and simultaneously collecting the required data. A removable glass cover had been used to study the effects of glazed and unglazed PVT panel situations. The research was conducted in February (winter) and July (summer), and March for daily solar radiation effects on efficiencies. The results indicated that electrical and thermal gains increased by the incre
... Show MoreThe holmium plasma induced by a 1064-nmQ-switched Nd:YAG laser in air was investigated. This work was done theoretically and experimentally. Cowan code was used to get the emission spectra for different transition of the holmium target. In the experimental work, the evolution of the plasma was studied by acquiring spectral images at different laser pulse energies (600,650,700, 750, and 800 mJ). The repetition rates of (1Hz and 10Hz) in the UV region (200-400 nm). The results indicate that, the emission line intensities increase with increasing of the laser pulse energy and repetition rate. The strongest emission spectra appeared when the laser pulse energy is 800mJ and 10 Hz repetition rate at λ= 345.64nm, with the maximum intensi
... Show MoreThe measurements of major and trace elements in different brands of milk powder selected from the Iraqis market via the X-ray fluorescence (XRF) Technique have been studied in the present work. The result of the measurements reveals the high concentrations of sodium, phosphorus, sulfur, chlorine, potassium, calcium and magnesium. Furthermore, low concentrations of aluminum, silicon, iron, bromine, molybdenum, iodine, barium, titanium, manganese, cobalt, chrome, nickel, copper, zinc and lead were detected. Neutron activation analysis (NAA) and Kjeldahl technique were also employed to determine the concentrations of nitrogen. It was found that the nitrogen concentration was in the range of (1.96 - 3.23) % which is within the permissible li
... Show MoreThe increasing complexity of how humans interact with and process information has demonstrated significant advancements in Natural Language Processing (NLP), transitioning from task-specific architectures to generalized frameworks applicable across multiple tasks. Despite their success, challenges persist in specialized domains such as translation, where instruction tuning may prioritize fluency over accuracy. Against this backdrop, the present study conducts a comparative evaluation of ChatGPT-Plus and DeepSeek (R1) on a high-fidelity bilingual retrieval-and-translation task. A single standardize prompt directs each model to access the Arabic-language news section of the College of Medicine, University of Baghdad, retrieve the three most r
... Show MoreThis histological study was carried out to compare between the thyroid gland of mice (as a model of the mammals) and the thyroid tissue of fish. Unlike mice, the thyroid gland of fish can't be recognized by naked eye. The present study revealed that the thyroid of mice varied from that of fish by the location and the histological structure. The study classified the physiological state of the thyroid of mice into three states and that of the fish into only two states. Accordingly, the study concluded that the metabolism of thyroid fish was of moderate type.
Grammatical particles are so important in understanding a text and its meaning in linguistic context. This paper " Grammatical Behavior and Uses of Negative and Prohibitive Particles in Semitic Languages: A Comparative Semitic Study"
tackles a very important topic in Semitic languages. Comparative studies in Semitic languages shed light on phenomena in different languages that are related or have one common origin. No doubt, such studies have their own effects on language study in general especially when studying a specific phenomenon and explaining it by reliance on the one origin, or by investigating the various phases of its historical development.
... Show MoreMany societies have some sports that play a pivotal role in enhancing human physical strength and martial arts and preserving religious values and beliefs. The most prominent of these traditional heroic sports are Zurkhaneh and Sumo, two sports that have their historical origins in the Iranian and Japanese cultural heritage. The research aims at shed light on the historical origins, symbolic rituals, and traditional elements of the sports of Zurkhaneh and Sumo, and to highlight the distinctive characteristics of the sports of Zurkhaneh and Sumo through objective analysis and comparison. The methodology used in this research is the historical approach, using the method of comparative analysis. This method includes analyzing information deriv
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