Based on an effective energy conversion method between gas enthalpy and thermal radiation, a multi-layered type of porous air heater has been proposed. In the five layered structure which is analyzed in this work, there are five porous layers which are separated by four quartz glass windows. The main layer operates as a porous radiant burner that products a large amount of thermal radiative ene...

introduction cr-39 detectors are widely used for radon and progeny measurement in the air. in this paper, using the monte carlo simulation, the possibility of using the cr-39 for direct measurement of radon and progeny in water is investigated. materials and methods assuming the random position and angle of alpha particle emitted by radon and progeny, alpha energy and angular spectrum that arri...

ZnSn1-x Gex N2 direct bandgap semiconductor alloys, with a crystal structure and electronic structure similar to InGaN, are earth-abundant alternatives for efficient, high-quality optoelectronic devices and solar-energy conversion. The bandgap is tunable almost monotonically from 2 eV (ZnSnN2 ) to 3.1 eV (ZnGeN2 ) by control of the Sn/Ge ratio.

Nitrogen fixation is essential for the synthesis of many important chemicals (e.g., fertilizers, explosives) and basic building blocks for all forms of life (e.g., nucleotides for DNA and RNA, amino acids for proteins). However, direct nitrogen fixation is challenging as nitrogen (N₂) does not easily react with other chemicals. By dry ball-milling graphite with N₂, we have discovered a simple, ...

This paper proposes a small wind energy conversion system comprises permanent magnet synchronous generator (PMSG), uncontrolled rectifier, conventional H-Bridge inverter and dc-dc bi-directional converter. The dc link capacitor is connected to a storage system through Bi-directional power flow link. A hybrid pulse width modulation (HPWM) controller is used to regulate the ac load voltage and fr...

We observe electron emission when vibrationally excited NO molecules with vibrational state v, in the range of 9 < or = v < or =18, are scattered from a Cs-dosed Au surface. The quantum efficiency increases strongly with v, increasing up to 10(-2) electrons per NO (v) collision, a value several orders of magnitude larger than that observed in experiments with similar molecules in the ground vib...

In this paper, the endothermic methanol decomposition reaction is used to obtain syngas by transforming middle and low temperature solar energy into chemical energy. A two-dimensional multiphysics coupling model of a middle and low temperature of 150~300 ◦C solar receiver/reactor was developed, which couples momentum equation in porous catalyst bed, the governing mass conservation with chemical...

The direct conversion of concentrated high temperature solar heat into electrical energy was demonstrated with a series of four–leg thermoelectric oxide modules (TOM). These temperature stable modules were not yet optimized for high efficiency conversion, but served as proof-of-principle for high temperature conversion. They were constructed by connecting two p(La1.98Sr0.02CuO4) and two n-type ...

Interfacing converters utilized in connecting energy storage systems like ultra capacitors and battery banks to wind generation systems introduce additional cost and power losses. This paper thus presents an immediate integration theme for ultra capacitors utilized in mitigating short-run power fluctuations in wind generation systems. This theme uses a dual electrical converter topology for eac...

This paper describes a high-efficiency, spectrum-splitting photovoltaic module that uses an off-axis volume holographic lens to focus and disperse incident solar illumination to a rectangular shaped high-bandgap indium gallium phosphide cell surrounded by strips of silicon cells. The holographic lens design allows efficient collection of both direct and diffuse illumination to maximize energy y...