10 research outputs found
Probabilistic Results on the Architecture of Mathematical Reasoning Aligned by Cognitive Alternation
We envision a machine capable of solving mathematical problems. Dividing the
quantitative reasoning system into two parts: thought processes and cognitive
processes, we provide probabilistic descriptions of the architecture
Preparation and Properties of Ce0.8Sm0.16Y0.03Gd0.01O1.9-BaIn0.3Ti0.7O2.85 Composite Electrolyte
Samarium, gadolinium, and yttrium co-doped ceria (Ce0.8Sm0.16Y0.03Gd0.01O1.9, CSYG) and BaIn0.3Ti0.7O2.85 (BIT07) powders were prepared by sol-gel and solid-state reaction methods, respectively. CSYG-BIT07 composite materials were obtained by mechanically mixing the two powders in different ratios and calcining at 1300 °C for 5 h. Samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), as well as electrical properties and thermal expansion coefficient (TEC) measurements. A series of CSYG-BIT07 composite materials with relative densities higher than 95% were fabricated by sintering at 1300 °C for 5 h. The performance of the CSYG-BIT07 composite electrolyte was found to be related to the content of BIT07. The CSYG-15% BIT07 composite exhibited high oxide ion conductivity (σ800°C = 0.0126 S·cm−1 at 800 °C), moderate thermal expansion (TEC = 9.13 × 10−6/K between room temperature and 800 °C), and low electrical activation energy (Ea = 0.89 eV). These preliminary results indicate that the CSYG-BIT07 material is a promising electrolyte for intermediate-temperature solid oxide fuel cells (IT-SOFCs)
Polymer nanocomposite dielectrics for capacitive energy storage
Owing to their excellent discharged energy density over a broad temperature range, polymer nanocomposites offer immense potential as dielectric materials in advanced electrical and electronic systems, such as intelligent electric vehicles, smart grids and renewable energy generation. In recent years, various nanoscale approaches have been developed to induce appreciable enhancement in discharged energy density. In this Review, we discuss the state-of-the-art polymer nanocomposites with improved energy density from three key aspects: dipole activity, breakdown resistance and heat tolerance. We also describe the physical properties of polymer nanocomposite interfaces, showing how the electrical, mechanical and thermal characteristics impact energy storage performances and how they are interrelated. Further, we discuss multi-level nanotechnologies including monomer design, crosslinking, polymer blending, nanofiller incorporation and multilayer fabrication. We conclude by presenting the current challenges and future opportunities in this field
Role of Manganese Oxide in Syngas Conversion to Light Olefins
The
key of syngas (a mixture of CO and H<sub>2</sub>) chemistry
lies in controlled dissociative activation of CO and C–C coupling.
We demonstrate here that a bifunctional catalyst of partially reducible
manganese oxide in combination with SAPO-34 catalyzes the selective
formation of light olefins, which validates the generality of the
OX-ZEO (oxide-zeolite) concept for syngas conversion. Results from
in situ ambient-pressure X-ray photoelectron spectroscopy, infrared
spectroscopy, and temperature-programmed surface reactions reveal
the critical role of oxygen vacancies on the oxide surface, where
CO dissociates and is converted into surface carbonate and carbon
species. They are converted to CO<sub>2</sub> and CH<sub><i>x</i></sub> in the presence of H<sub>2</sub>. The limited C–C coupling
and hydrogenation activities of MnO enable the reaction selectivity
to be controlled by the confined pores of SAPO-34. Thus, a selectivity
of light olefins up to 80% is achieved, far beyond the limitation
of Anderson–Shultz–Flory distribution. These findings
open up possibilities to explore other active metal oxides for more
efficient syngas conversion