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In this work, simulation-based equations to calculate propagation constant in uniform or periodic structures (SES) are deduced and verified through simulations in various types of structures. The modeling of those structures are essentially based on field distributions from a driven-mode solver, and the field distributions are used as the input parameters of the FPPS. It allows the separation of forward and backward waves from a total wave inside such a uniform or periodic structure, and thus it can be used to calculate the propagation constants inside both uniform and periodic structures even with a strong reflection. In order to test the performance and function of the FPPS, it has been applied to a variety of typical structures, including uniform waveguides, lossfree closed structures, lossy closed structures, and open radiation structures, and compared with the results of eigenmode solvers, equivalent network methods, and spectral domain integral equation methods. The comparison shows the easy-to-use and adaptable nature of the FPPS. the FPPS. This FPPS could be also applied to open radiating structures, and even multi-dimensional periodic/uniform structures., Comment: 10 pages, 13 figures

Methanol decomposition on Ni(111) surfaces has been studied in the presence and absence of oxygen using temperature-programmed desorption and temperature-dependent sum frequency generation spectroscopy. Under both conditions the C–H and O–H bonds break, forming carbon monoxide and atomic hydrogen on the surface. No C–O bond scission was observed, limiting the number of reaction pathways. The O–H bonds break first (>150 K), forming surface methoxy, followed by C–H bond breakage (>250 K). All atomic hydrogen desorbs from the surface as H2 through H+H recombinative desorption. H2 desorbs at a higher temperature in the presence of oxygen (>300 K) than the absence of oxygen (>250 K) as the oxygen on the surface stabilizes the H atoms, forming surface hydroxide (OH). The surface oxygen also appears to stabilize the O–H and C–H bonds, leading to slightly higher dissociation temperatures. The CO molecules occupy both the bridge sites and the top sites of the Ni atoms as surface H appears to force the CO molecules to the top sites. There is a slight blueshift in the C–O bond vibration for both the O covered and O free surfaces due to CO being more mobile. On the O free surface, the C–O peak width broadens as low-frequency modes are activated. Finally, CO desorbs between 350 and 400 K.

Discussion can be an important and powerful tool in efforts to build a more diverse, equitable, and inclusive future for STEM (i.e., science, technology, engineering, and mathematics). However, facilitating discussions on difficult, complex, and often uncomfortable issues, like racism and sexism, can feel daunting. We outline a series of steps that can be used by educators to facilitate productive discussions that empower everyone to listen, contribute, learn, and ultimately act to transform STEM.

Catalysis provides pathways for efficient and selective chemical reactions through the lowering of energy barriers for desired products. Gold nanoparticles (AuNP) show excellent promise as plasmonic catalysts. Localized surface plasmon resonances are oscillations of the electron bath at the surface of a nanoparticle that generate energetically intense electric fields and rapidly decay into energetically excited electrons. The excited electrons have the potential to destabilize strongly bound oxygen atoms through occupation of accessible anti-bonding orbitals. Tuning the anti-bonding orbitals to make them accessible for occupancy will be achieved by coating the AuNP in a thin layer of another transition metal, such as ruthenium, silver, or platinum, creating a bimetallic nanoparticle. We will initially study the carbon monoxide (CO) oxidation reaction, where the oxygen species is strongly bound and limits reactivity, in the presence of ruthenium-gold bimetallic nanoparticles (Ru-AuNPs). The bond between oxygen and ruthenium is typically strong, which inhibits reaction rates. Excited electrons from the AuNPs can transfer to the oxygen-ruthenium anti-bonding orbital. Electrons occupy the anti-bonding orbital, weakening the bond between the atomic oxygen and the Ru-AuNPs and making the atomic oxygen much more reactive. We will be studying the physical and chemical characteristics of the synthesized Ru-AuNP catalysts with spectroscopic and microscopic techniques including: UV Vis spectroscopy, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and transmission electron microscopy (TEM).

The paper presents a comparative study of two types of remote area power supply (RAPS) systems, which are the existing photovoltaic-based (PV) configuration and the proposed thermoelectric-based (TE) configuration. Both RAPS systems are solar-based power generators and sized according to Melbourne weather conditions (latitude 37.5o S). In this study, the RAPS system designs for both PV and TE have no backup generator and the batteries are the only device for electrical energy storage. Battery storage is used for storing solar energy during the available days for meeting the energy demand as required. The presented RAPS systems for this comparative study are PV/Battery and TE/Battery configurations. Generally, both PV and TE cells are solar-based power generating cells but they have different pre-conversion inputs. For electrical power generation, PV uses sunlight as input energy while the TE uses concentrated solar heat. The results show that the total setup cost for TE/Battery system is 66% higher than PV/Battery system under similar design requirements. Despite having higher setup cost, the TE/Battery system has the potential to harness both electrical and thermal energy for domestic purposes

Graphitic carbon nitride (g-C3N4) contains a high C/N ratio of 3/4; however, utilizing nitrogen atoms in pseudocapacitive energy storage systems remains a challenge due to the limited number of edge nitrogen atoms and inherent poor electrical conductivity of this semi-conductor material. 3D oxidized g-C3N4 functionalized graphene composites (GOOCN24), in which reduced graphene oxide providing high electron conductivity acts as a skeleton and hybridises with oxidized g-C3N4 segments, were synthesized using a facile two-step solution-based method. Due to the pre-oxidation treatment of g-C3N4, which breaks the polymeric nature of g-C3N4 and increases in the proportion of edge nitrogen atoms and the subsequent solubility in water, the GOOCN24 composites used as electrodes for supercapacitors show a specific capacitance as high as 265.6 F g−1 in acid electrolyte and 243.8 F g−1 in alkaline electrolyte in three-electrode configuration at a current density of 1 A g−1. In addition, low internal resistance, excellent rate performance of over 74% capacitance retention (over a 50-fold increase in current density), and outstanding cycling stability of over 94% capacitance retention after 5000 cyclic voltammetry cycles in both alkaline and acid electrolytes was attained. This translated into excellent energy density with appropriate power density when demonstrated in a symmetrical device.