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Single-Phase and Three-Phase Distribution Systems
Published in Dale R. Patrick, Stephen W. Fardo, Brian W. Fardo, Electrical Power Systems Technology, 2021
Dale R. Patrick, Stephen W. Fardo, Brian W. Fardo
However, a longer section of electrical conductor has a higher resistance. Therefore, it is sometimes necessary to limit the distance a conductor can extend from the power source to the load that it supplies. Many types of loads do not operate properly when a value less than the full source voltage is available.
Direct Current (dc) Electronics
Published in Dale R. Patrick, Stephen W. Fardo, Electricity and Electronics Fundamentals, 2020
Dale R. Patrick, Stephen W. Fardo
A material through which current flows is called a conductor. A conductor passes electric current very easily. Copper and aluminum wire are commonly used as conductors. Conductors are said to have low resistance to electrical current flow. Conductors usually have three or fewer electrons in the outer orbit of their atoms. Remember that the electrons of an atom orbit around the nucleus. Many metals are electrical conductors. Each metal has a different ability to conduct electric current. Materials with only one outer orbit or valence electron (gold, silver, copper) are the best conductors. For example, silver is a better conductor than copper, but it is too expensive to use in large amounts. Aluminum does not conduct electrical current as well as copper, but it is commonly used, since it is cheaper and lighter than other conductors. Copper is used more than any other conductor.
Electrical Power Systems/Improved Efficiency
Published in Dale R. Patrick, Stephen W. Fardo, Ray E. Richardson, Brian W. Fardo, Energy Conservation Guidebook, 2020
Dale R. Patrick, Stephen W. Fardo, Ray E. Richardson, Brian W. Fardo
However, a longer section of electrical conductor has a higher resistance. Therefore, it is sometimes necessary to limit the distance a conductor can extend from the power source to the load which it supplies. Many types of loads do not operate properly when a value less than the full source voltage is available. This situation can reduce the energy efficiency of equipment.
Drilling of titanium alloy (Ti6Al4V) – a review
Published in Machining Science and Technology, 2021
Chua Guang Yuan, A. Pramanik, A. K. Basak, C. Prakash, S. Shankar
This machining process can be done on almost any type of material, provided that the material is an electrical conductor (Ramasawmy and Blunt, 2004). Similar to laser drilling, workpiece does not make direct contact with electrode during the electrical discharge machining (EDM) process. Since workpiece and cutter are not mechanically contacted, not only frictional heat is very much eliminated, mechanical stresses and vibrations from workpiece are eliminated as well (Ho and Newman, 2003; Pramanik and Basak, 2018). EDM is widely applicable to dies and mold forming. Due to the simplicity and superior advantages of EDM over conventional machining, micro-EDM drilling is widely applied by industries performing fabrication of micro-holes (Sapkal and Jagtap, 2018). Although micro-EDM drilling process shown superior quality over CD for titanium alloy, several constraints and limitations are reported to decrease efficiency of EDM drilling process (Abbas et al., 2007). It is reported that quality and surface integrity of holes drilled on titanium alloy are greatly affected by MRR and electrode wear (EW) rate (Jabbaripour et al., 2012; Tiwary et al., 2015).
Robust modelling and prediction of the COVID-19 pandemic in Canada
Published in International Journal of Production Research, 2021
Soheyl Khalilpourazari, Hossein Hashemi Doulabi
SFS starts optimisation by initiating a set of particles (random solutions in the solutions space). Then, it assigns a specific amount of electric energy to each particle as follows: In this relation, stands for the number of particles, E represents the total initial energy, and shows the amount of electric energy assigned to particle . SFS utilised the diffusion process to produce new solutions around each solution in the initial set to create new solutions. The diffusion process is inspired by the dielectric breakdown process in which an electrically insulating material abruptly converts to an electrical conductor under immense voltage. The phenomenon allows the electric current to go through it, creating fractal shapes.
Development of a new vacuum impregnation method at room atmosphere to produce silver–copper oxide nanoparticles on activated carbon for antibacterial applications
Published in Environmental Technology, 2020
Flávia Sayuri Arakawa, Quelen Letícia Shimabuku-Biadola, Marcela Fernandes Silva, Rosangela Bergamasco
XRD patterns of the impregnated samples (CuO:Ag(1:0.3), CuO:Ag(1:0.3)t, CuO:Ag(1:0.5), and CuO:Ag(1:0.5)t) indicated that the temperature reduction at 350°C and room atmosphere was effective at converting metal salts of precursors into their respective metallic or oxide states. The crystalline phases identified showed that silver nitrate was reduced to silver metallic crystals. Silver metal is an electrical conductor, and thus crystals can grow by Ag+ reduction on a silver crystallite surface [48]. Diffraction peaks were found in all modified samples at 2θ angles of 38.1° and 44.2° and assigned to the (111) and (200), respectively, and can be assigned to planes of silver metal as reported by Khare, Sharma [16], Park and Jang [49]. Copper impregnation onto AC was also confirmed and corresponded to copper oxide (CuO). Additionally, it was found in the metallic copper phase. Higher copper impregnation in the raw material led to the enrichment of copper oxide on the surface of the AC, indicating that copper salt impregnation determined the amount of copper oxide product on the surface after thermal decomposition had completed. Two characteristic peaks were observed at 2θ angles of 35.4° and 61.2° corresponding to the (111) and (202) crystalline planes of the CuO phase [50].