The fluorine doped cadmium oxide samples have been deposited at 250
°C by ultrasonic spray pyrolysis method. X-ray diffraction patterns of the CdO:F samples have revealed that the samples are ...polycrystalline with cubic sodium chloride structure. The texture coefficients calculated for various planes at different fluorine concentrations indicate that the samples have exhibited (1
1
1) and (2
0
0) preferential orientations. The lattice parameters for cubic structure of each diffraction plane have been calculated. The crystallite size of the samples being nearly constant until 4% of fluorine doping showed reasonable decrease above this concentration value. The macro strain and dislocation density vary with fluorine concentrations.
Neural differential equations have recently emerged as a flexible data-driven/hybrid approach to model time-series data. This letter experimentally demonstrates that if the data contains ...oscillations, then standard fitting of a neural differential equation may result in a "flattened out" trajectory that fails to describe the data. We then introduce the multiple shooting method and present successful demonstrations of this method for the fitting of a neural differential equation to two datasets (synthetic and experimental) that the standard approach fails to fit. Constraints introduced by multiple shooting can be satisfied using a penalty or augmented Lagrangian method.
Cobalt oxide films have been produced by chemical bath deposition technique at various bath temperatures for different deposition times onto glass substrates. The as-grown Co3O4 films were annealed ...at 300 °C for 1 h and investigated via x-ray diffraction, field emission scanning electron microscopy. The x-ray diffraction patterns have revealed that the annealed samples are polycrystalline with face-centered-cubic structure. The cubic phase is clearly seen in the form of long rods from micrographs. The band gap of the Co3O4 thin films was determined using absorption spectra. The samples have exhibited direct transition with the band gap values lying in the range between Eopt1 = 1.40–1.49 eV and Eopt2 = 2.02–2.19 eV. The refractive index and extinction coefficient as a function of wavelength were investigated from reflectance spectrum by applying the envelope method. The optical parameters of the Co3O4 film, such as dielectric constants, plasma frequency, and carrier concentration, were also evaluated. The electrical properties of the samples constructed planar structure have been measured in the dark at room temperature by applying the voltage values between 1 and 100 V.
•Preparation of Co3O4 films by chemical bath deposition.•Cubic Co3O4 nanorods were produced.•Effect of bath temperature and deposition time on the crystal structure.•Five obvious optical transitions were identified.•Optical parameters were evaluated from reflectance spectrum by applying the envelope method.
•A wide range of reported, experimental data were used to compare mechanisms.•All the mechanisms are found to be inaccurate.•The most plausible mechanism has a selectivity error of 17%.
Numerous ...mechanisms have been proposed for the direct, homogeneous, partial oxidation of methane to methanol system. No thorough comparison of them to experimental data, and to each other, has been reported. In this work six mechanisms are tested against over 200 operating points from published literature. All the examined mechanisms are found to be inaccurate, with the most accurate mechanism, MVedeneev,C1 (Arutyunov et al., 1996), having an average selectivity error of 17%. In addition, it was found that some mechanisms showed behaviour that was not observed in the literature and were deemed unsuitable for the reaction system. As such all of the available mechanisms do not adequately describe the gas phase methane to methanol system.
This work reviews and expands upon the previous fluorination processes for in situ production of oxygen and silicon from lunar regolith. The process units were simulated and a flow sheet was ...developed to determine the product distribution and energy requirements. Our results show that 0.21 kg silicon and 0.32 kg oxygen can be produced per kg regolith processed with a total cooling duty of 17 MJ/kg regolith and electrical duty of 29 MJ/kg regolith. The payload mass required for the process is estimated as 16 kg/kg regolith processed per day.
Neural differential equations have recently emerged as a flexible data-driven/hybrid approach to model time-series data. This work experimentally demonstrates that if the data contains oscillations, ...then standard fitting of a neural differential equation may result in a flattened out trajectory that fails to describe the data. We then introduce the multiple shooting method and present successful demonstrations of this method for the fitting of a neural differential equation to two datasets (synthetic and experimental) that the standard approach fails to fit. Constraints introduced by multiple shooting can be satisfied using a penalty or augmented Lagrangian method.
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