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Electromagnetic Compatibility
Published in Ahmad Shahid Khan, Saurabh Kumar Mukerji, Electromagnetic Fields, 2020
Ahmad Shahid Khan, Saurabh Kumar Mukerji
Electromagnetic compatibility refers to the ability of an electrical or electronic system to operate properly in a disturbing electromagnetic environment and without disturbing the operation of other systems or components of other equipment. It basically addresses the issues of “emission” and “susceptibility” or “immunity”. Emission refers to the unwanted generation of electromagnetic energy by various sources, and the required countermeasures. These measures are required to reduce such generation and to prevent the escape of energy into the external environment. Susceptibility (or immunity) refers to the correct operation of electrical equipment (the “victim”) in the presence of electromagnetic disturbances. To achieve electromagnetic compatibility, both of these issues are to be properly addressed. Interfering sources must be suppressed and the potential victims fortified. In addition, the coupling paths between the sources and victims are also to be thoroughly studied and addressed so as to minimize electromagnetic interference.
Catalytic Surfaces and Catalyst Characterization Methods
Published in James J. Carberry, Arvind Varma, Chemical Reaction and Reactor Engineering, 2020
W. Nicholas Delgass, Eduardo E. Wolf
While the detailed physics of electron emission by photoexcitation, is quite complex, the basic principle is straightforward and has been known for decades. Emission of electrons occurs when matter is exposed to or excited by electromagnetic radiation or photons. If the photons have energies in the ultraviolet range, they cause ejection of the less tightly bound valence electrons that emerge at discrete energies [ultraviolet photoelectron spectroscopy (UPS)]. If the incoming photons are x rays of suitable energies (1 to 3 keV or soft x rays), ejection of inner or core electrons occurs. If the energy of the incoming photons is known, analysis of the energy of the emitted electrons permits calculation of core electron binding energies. Since the electron binding energies are quantized, the emitted electrons have discrete energies that reflect the electronic structure of the parent atom and thus identify the irradiated element.
Elemental Ferromagnetic Nanomaterials
Published in Sam Zhang, Dongliang Zhao, Advances in Magnetic Materials, 2017
Suneel Kumar Srivastava, Samarpita Senapati
The rapid growth of wireless communication, information technology, high- frequency circuit devices (in the GHz range), and radar stealth systems also contribute toward environmental pollution. This is due to the emission of EM irradiations causing the malfunctioning of electronic devices as well as an adverse effect on biological systems [139,435]. Therefore, the soft metallic magnets remain the most preferred choice for EM wave absorption at high frequency over the gigahertz range due to high saturation magnetization and Snoek’s limit [436]. As a consequence, nanoparticles of Fe [14,139,254,437–440], Co [323], Ni [441], Fe@C [442–446], Fe@ ZnO [447,448], Ni–P-coated Fe [449], Fe/SiO2 [14,142,274], Ag-coated Fe/SiO2 [14], Fe/SnO2 [450], C-coated Co [451], polymer-protected Co [31], C-coated Ni [446,452], CuO/Cu2O-coated Ni [453], Ni/polypyrrole [28], Ni/graphene [29,30], Fe/Fe2O3, and Ni/NiO [326] have been investigated as EM wave absorbing materials.
Hydrolysis of carbonyl sulfide over modified Al2O3 by platinum and barium in a packed-bed reactor
Published in Chemical Engineering Communications, 2021
K. Nimthuphariyha, A. Usmani, N. Grisdanurak, E. Kanchanatip, M. Yan, S. Suthirakun, S. Tulaphol
Pulverized coal-fired technology has been applied for electricity generation for several years. This process directly combusts pulverized coal to produce high-pressure steam to generate electricity. This technology provides the net efficiency only 50%, approximately (Bugge et al. 2006). To utilize the energy more efficient, an alternative technology like “integrated gasification combined cycle (IGCC)” has been introduced. It has shown an excellent performance compared to the pulverized coal-fired process. IGCC is the high-pressure gasification process to produce synthetic gas combined with gas turbine combined cycle (GTCC) (Descamps et al. 2008). The high heating value syngas is utilized in steam turbine for generating electricity. After the gas cleaning units, H2 separated from the syngas can be further utilized in fuel cell units. The process provides more advantage by including pre and post CO2 capture units to reduce global warming emissions. However, carbonyl sulfide (COS) emission generated from gasification could be one of drawbacks of this technology. COS, produced from sulfur content in coal, can harm the fuel cell system. The emission can harm human health and environment (Zulkefli et al. 2019). As a result, COS in the exhaust stream should be taken care of.
Synthesis, crystal structure, vibrational, optical properties, and a theoretical study of a new Pb(II) complex with bis(1-methylpiperazine-1,4-diium): [C5H14N2]2PbCl6·3H2O
Published in Journal of Coordination Chemistry, 2019
Mohamed Lahbib Mrad, Souhir Belhajsalah, Mohammed Said M. Abdelbaky, Sergio García-Granda, Khaled Essalah, C. Ben Nasr
Supporting Information Figure S11 shows the emission spectrum of [C5H14N2]2PbCl6·3H2O. The sample exhibits one strong peak at 500 nm (2.48 eV) when excited at 370 nm (3.35 eV) (Supporting Information Figure S11), which can even be observed with the naked eye at room temperature. Previous work on various organic inorganic hybrid compounds has revealed that the strong luminescence arises from an exciton state [59]. The luminescence originates from electronic transitions within the inorganic portions. The peak at 500 nm arises from exciton recombination within the inorganic portions [60]. Under excitation, an electron is excited from the valence band (VB) to the conduction band (CB), leaving a hole in the valence band. The electron transition back to the ground state, that is the recombination of the electron and hole, yields an emission.
A profile on the CardioMEMS HF system in the management of patients with early stages of heart failure: an update
Published in Expert Review of Medical Devices, 2023
Rohit Vyas, Mitra Patel, Samer J. Khouri, George V. Moukarbel
Abbott has also found that certain CardioMEMS patient electronic systems (Models CM1000, CM1010, and CM1100) and CardioMEMS hospital electronics systems (Model CM3000 only) may emit radiofrequencies at levels that are higher than those listed in the instructions for use. These higher-level emissions have the potential to cause interference with other medical devices such as pacemakers, implantable defibrillators, or neurostimulators. Since 2014, there have been only two reported instances of potential interference with no resultant patient harm or adverse events. Based on testing and evaluation performed by Abbott, higher-level emissions do not appear to impact the ability of the device to accurately read sensor data [47].