This work studies the impact of input machining parameters of Electrical Discharge Machining (EDM) on the machining process performance. Tool steel O1 was selected as the workpiece material, copper as the electrode material, and kerosene as the dielectric medium. Experimental runs have been carried out with a Design of Experiment (DOE) technique. Twenty tests are accomplished with the current range of (18 to 24 Ampere), a pulse duration range of (150 to 200 µs), and a pulse-off time range of (25 to 75 µs). Based upon the experimental study's output results, the EDM parameter's effect (voltage of power supply, discharge current, pulse duration, and pulse pause interval) on the responses of the process represented by surface roughness value Ra and Metal Removal MR rate. The results obtained by the DOE approach are analyzed by STATISTICA software. It has been concluded that an increase in the current and pulse duration maximizes both metal removal rate and surface roughness. At the same time, they are minimized by maximizing the pulse pause interval.
A new ligand [3(3(2chloroacetyl) thioureido)pyrazine-2-carboxyliIcacid](CPC)was synthesized by reaction of rized by imicro elmental analysis C.H.N.S.,FT-IR,UV-Vis and 1H-13CNMR spectra, some transition metals complex ofIthis ligand were Prepared and characterized byiFT-IR,UV-Vis spectra conductivity measurements magnetic susceptibility and atomic absorption. From the obtained results the molecular formula of all prepared complexes were[M(CPC)2](M+2i=Mn. Co, Ni, Cu, Zn, Cd and Hg),the proposedi geometrical structure for all complexes were as tetrahedral geometry except copper complex has square planer geometry.
The study aims to examine the problem of forced displacement and its social and economic problems in light of the Syrian crisis. Such an aim helps to know the difficulties and challenges facing the children of displaced families in learning, and the reasons for their lack of enrolment. It also clarifies whether there are significant statistical differences at among the attitudes of the children of the displaced families towards education regarding the following variables: (the work of the head of the family, the economic level of the family, and the work of the children). The study has adopted the descriptive-analytical approach; a questionnaire was adopted as a tool to collect information. The study was applied to a sample o
... Show MoreAcidity constants at 30co and 0.125 ionic strength have been determined for the Nitrogous bases of nucleic acid; cytocine, uarcil and thymine, and found to be 3.55 x10-19 , 1.44 x10 -19 and 7.24 x10 -20 respectively. Stability constants of these bases with Thorium and uranyl ions have been determined. Results showed that metal ions Thorium and uranyl ions behave as hard acids and the nitrogenum bases behave as Hard bases according to Pearson's definition .Hardness – softness parameters for these ligands were calculated ,stability constants of complexes with metal ions could be arranged as follows :- Cytosine > Uracil > Thymine .
High-power density supercapacitors and high-energy–density batteries have gotten a lot of interest since they are critical for the power supply of future electric cars, portable electronic gadgets, unmanned aircraft, and so on. The electrode materials used in supercapacitors and batteries have a significant impact on the practical energy and power density. Metal–organic frameworks (MOFs) have the outstanding electrochemical ability because of their ultrahigh porous structure, ease of functionalization, and great specific surface area. These features make it an intriguing electrode material with good electrochemical efficiency for high-storage batteries. Thus, this review summarizes current developments in MOFs-based materials as an elec
... Show MoreThe researchers of the present study have conducted a genre analysis of two political debates between American presidential nominees in the 2016 and 2020 elections. The current study seeks to analyze the cognitive construction of political debates to evaluate the typical moves and strategies politicians use to express their communicative intentions and to reveal the language manifestations of those moves and strategies. To achieve the study’s aims, the researchers adopt Bhatia’s (1993) framework of cognitive construction supported by van Emeren’s (2010) pragma-dialectic framework. The study demonstrates that both presidents adhere to this genre structuring to further their political agendas. For a positive and promising image
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