The influence of the grounded electrode area on the ignition voltage in capcitively coupled radio frequency discharge at 13.56 MHz in argon gas is studied experimentally. The results indicate a systematic decrease of the breakdown voltage with increasing grounded electrode area for the same pd value. Results show that the secondary ionization coefficient γ increases with the increase of grounded electrode area. Furthermore, results also the discharge current at the breakdown voltage increases almost linearly with the increase of electrode area suggesting an almost constant current density.
The effects of poles distances of a discharge tube (cathode and anode) were investigated. The distances(90,95,100,110,115,120,130,140)mm are considered. The influence of (25mT) parallel and (2mT) normal magnetic fields with respect to the discharge tube on electron temperature under a pressure of (6pascal) and (900volt) was studied by implementing double Langmuire probe into plasma. Curves fitting were performed to find the optimum values of electron temperature for all cases in this work.We found that the electron temperature as a function of poles distances is exponential form
Gold, silver and nickel used as electrodes in the fabrication of perovskite solar cell by using thermal evaporation deposition method with direct structure FTO\ TiO2\ MAPbI3\ spiro-MeOTAD\ metal electrode. The cell efficiency was compared between the electrodes material as a function of time to explaining the effect of these metals electrode on cell performance, X-ray diffraction pattern showed that the samples that contain gold and nickel do not contain a compound indicating the interaction of the metal with the components of the cell or the formation of a new compound, while in the cell containing silver it was found that silver iodide is fo
Electrical Discharge Machining (EDM) is a widespread Nontraditional Machining (NTM) processes for manufacturing of a complicated geometry or very hard metals parts that are difficult to machine by traditional machining operations. Electrical discharge machining is a material removal (MR) process characterized by using electrical discharge erosion. This paper discusses the optimal parameters of EDM on high-speed steel (HSS) AISI M2 as a workpiece using copper and brass as an electrode. The input parameters used for experimental work are current (10, 24 and 42 A), pulse on time (100, 150 and 200 µs), and pulse off time (4, 12 and 25 µs) that have effect on the material removal rate (MRR), electrode wear rate (EWR) and wear ratio (WR). A
... Show MoreThis research is devoted to design and implement a Supervisory Control and Data Acquisition system (SCADA) for monitoring and controlling the corrosion of a carbon steel pipe buried in soil. A smart technique equipped with a microcontroller, a collection of sensors and a communication system was applied to monitor and control the operation of an ICCP process for a carbon steel pipe. The integration of the built hardware, LabVIEW graphical programming and PC interface produces an effective SCADA system for two types of control namely: a Proportional Integral Derivative (PID) that supports a closed loop, and a traditional open loop control. Through this work, under environmental temperature of 30°C, an evaluation and comparison were done for
... Show MoreIn this work, seven soil samples were brought brought to study and analyses the element concentrations from different southern regions of Iraq using laser-induced breakdown spectroscopy (LIBS) technique. It has been documented as an atomic emission spectroscopy (AES) technique. Laser-induced plasma utilized to analyze elements in materials (gases, liquids, and solids). In order to analyze elements in materials (gases, liquids, and solid). The Nd: YAG laser excitation source at 1064 nm with pulse width 9 ns is used to generate power density of 5.5 x 1012 MW/mm2, with optical spectrum in the range 320-740 nm. From this investigation, the soil sample analysis of the southern cities of Iraqi, it is concluded that the rich soil element of P, Si,
... Show MoreIn this work, different soil samples were brought to study and analyse the element concentrations from different middle regions of Iraq (such as, Habbaniah, Garmah, Fallujah, and Tarmiah cities). Using laser-induced breakdown spectroscopy (LIBS) has been documented as an atomic emission spectroscopy (AES) technique. Laser-induced plasma utilized to analyse elements in materials (gases, liquids, and solids) in order to analyse elements in materials (gases, liquids and solid). The Nd:YAG laser excitation source at 1064nm with pulse width and pulse duration of 9ns is used to generate power density of 5.5 x 1012 MW/mm2, with optical spectrum in the range 320 -740 nm.
The soils of Habbaniyah and Garmah citi
... Show MoreComsol multiphysics software is established to make a simulation that is comparable with experimental device. by utilizing comsol, the positive column domain of direct-current glow discharge with argon is considered for both of different applied voltage and working gas pressure. The calculations are exhibited by using a precise collision cross sections and Townsend coefficients for the argon. The impacts of voltage and pressure on the Debye length, number of particles in Debye sphere and plasma frequency are calculated and graphically delineated. With this regard to the dependence of plasma parameters on the applied voltage and pressure, some of them are found to be compatible with the experimental
... Show MoreThe appearance of Mixed Mode Oscillations (MMOs) and chaotic spiking in a Light Emitting Diode (LED) with optoelectronic feedback theoretically and experimentally have been reported. The transition between periodic and chaotic mixed-mode states has been investigated by varying feedback strength. In incoherent semiconductor chaotically spiking attractors with optoelectronic feedback have been observed to be the result of canard phenomena in three-dimensional phase space (incomplete homoclinic scenarios).
The microwave induced plasma jet (MIPJ) system was built using local materials and based on a tapered waveguide. The parameters of this plasma were determined like electron temperature Te, electron density ne. the other parameters such as plasma frequency( fp), the Debye length( λD), and the number of particles in the Debye sphere( Nd) It has also been studied. The study were done at different Ar flow rate ranging from (2-10) l/m and a discharge tube diameter ranging from (2-10) mm. all of these parameters were determined depending on the MIPJ spectrum. it turned out that there is a high possibility of controlling the parameters of MIPJ through manipulating these parameters.