The C4=C5 double bond of 2-aminooxazole serves as dienophile in the course of inverse electron-demand Diels- Alder reactions with 1,2,4-triazines. The primary tricyclic adducts would lose dinitrogen molecule to form fused oxazolopyridine core whose aminooxazoline moiety undergoes extrusion of HOCN species, which finally leads to 3- or 4-aminopyridines. The regioselectivity of the process is governed by the substitution pattern of the triazine core.
Research on sustainable energy storage and conversion techniques is advancing due to rising energy use. Supercapacitors, high-power-density capacitors, are in high demand due to their quick energy release and absorption capabilities. In this study, NiO/Co3O4/BaO/Al2O3 (NCBA) and NiO/Co3O4/BaO/Al2O3@g-C3N4 (NCBACN) nanocomposites were synthesized, characterized, and their electrochemical performance was checked as a supercapacitor and for photodegradation of dyes. The NCBA and NCBACN nanocomposites were prepared using co-precipitation and ultra-sonication methods. The NCBACN electrode had a higher specific capacitance (2190 F/g) than the NCBA electrode (476 F/g). NCBACN demonstrated superior efficiency in reducing Rhodamine-B and Congo red dyes, with 97
In this paper, we consider the continuous mode of volumetric crystallization with mass/heat exchange with the surrounding medium. A nonlinear mathematical model of kinetic and balance equations, boundary and initial conditions, taking into account the diffusion mechanism of particles in the space of their sizes, the removal of product crystals and mass/heat inflow/outflow is formulated. An exact analytical solution describing steady-state mode of continuous crystallization is derived with allowance for the Heaviside step classification functions that specify the size dependence of product removal and fines dissolution. The steady-state crystal-size distribution and growth rate of crystals are compared with the experimental data for lactose and sucrose crystallization. The theory is in good agreement with the experimental data.
In this paper, we analyze the population-balance model for the evolution of numerous particles of different sizes during the intermediate step of volumetric phase transition. We use the approximation of spherical particle shapes and neglect interactions between them, considering the average interparticle distance to be much greater than the characteristic radius of the particles. The population-balance model under consideration includes a second-order Fokker–Planck equation for the distribution function, an integro-differential equation for mass conservation, initial and boundary conditions. This model is analytically solved in the case when the growth rate of particles solely depends on their radius. The particle-radius distribution, solution supersaturation, and the moments of the distribution function are derived analytically for various mass flows entering and leaving the solution during product crystal growth. Numerical calculations are carried out for the growth of insulin crystals in the case of two-step crystallization mechanism.
The development of low-temperature solid oxide fuel cells (LT-SOFCs) is of significant importance for realizing the widespread application of SOFCs. This has stimulated a substantial materials research effort in developing high oxide-ion conductivity in the electrolyte layer of SOFCs. In this context, for the first time, a dielectric material, CaCu3Ti4O12 (CCTO) is designed for LT-SOFCs electrolyte application in this study. Both individual CCTO and its heterostructure materials with a p-type Ni0.8Co0.15Al0.05LiO2−δ (NCAL) semiconductor are evaluated as alternative electrolytes in LT-SOFC at 450–550 °C. The single cell with the individual CCTO electrolyte exhibits a power output of approximately 263 mW cm−2 and an open-circuit voltage (OCV) of 0.95 V at 550 °C, while the cell with the CCTO–NCAL heterostructure electrolyte capably delivers an improved power output of approximately 605 mW cm−2 along with a higher OCV over 1.0 V, which indicates the introduction of high hole-conducting NCAL into the CCTO could enhance the cell performance rather than inducing any potential short-circuiting risk. It is found that these promising outcomes are due to the interplay of the dielectric material, its structure, and overall properties that led to improve electrochemical mechanism in CCTO–NCAL. Furthermore, density functional theory calculations provide the detailed information about the electronic and structural properties of the CCTO and NCAL and their heterostructure CCTO–NCAL. Our study thus provides a new approach for developing new advanced electrolytes for LT-SOFCs.
