Introduction: NASA is evaluating various methods to process lunar and Mars regolith in preparation for future missions. We have performed earlier studies [1-3] to understand the mechanism associated with the lunar regolith’s excellent absorbtion of microwave energy that is useful for microwave processing. Using an upgraded microwave heating facility we have shown that the previously observed [4...

microwave-assisted hydrodistillation (mahd) method has been compared with hydrodistillation (hd) conventional technique for extraction of essential oil from achillea millefolium. microwave-assisted hydrodistillation were examined at three levels of microwave powers (300, 500, and 700 w) .   obtained results show that   mahd offers important advantages over hd in terms of energy savings and extr...

PURPOSE The impact strength and the flexural properties of denture base materials are of importance in predicting their clinical performance upon sudden loading. This study compares the impact and transverse strengths and the flexural modulus of three denture base polymers. MATERIALS AND METHODS The investigation included a relatively new microwave-polymerized polyurethane-based denture mater...

Microwave heating is a dielectric heating process, in which heat is generated via the interaction of dielectric materials with electromagnetic radiation. The dielectric constant is a measure of the material’s capacity to retard microwave energy as it passes through, while the loss factor is a measure of the material’s capacity to dissipate the energy. The materials with high loss factor are eas...

The efficiencies of different transformation methods of E. coli DH5Qalpha train, induced by several cations like Mg2+, Mn2+ Rb+ and especially Ca2+, with or without polyethylene glycol (PEG) and dimethyl sulfoxide (DMSO) were compared using the two commonly used plasmid vectors pCAMBIA1201 and pBI121. The widely used calcium chloride (CaCl2) method appeared to be the most efficient procedure, w...

The material properties of greatest importance in microwave processing of a dielectric are the complex relative permittivity ε = ε′ jε′′, and the loss tangent, tan δ = ε′′/ ε′. The real part of the permittivity, ε′, sometimes called the dielectric constant, mostly determines how much of the incident energy is reflected at the air-sample interface, and how much enters the sample. This paper show...

the composite powders of barium-magnesium ferrite were prepared using sol-gel auto-combustion and microwave methods. the crystal structure and the shape of nanocomposites have been compared. x-ray diffraction (xrd), scanning electron microscope (sem) and vibrating sample magnetometer (vsm) were used to investigate the structural, morphological and magnetic properties of nanopowder. the formatio...

777 Thinking Coherently About the Second Law The efficiency of heat engines has been limited by the Carnot cycle, which states that the efficiency cannot exceed 1 – Tc/Th, where Tc and Th are the absolute temperatures of the cold and hot reservoirs feeding the engine. Scully et al. (p. 862; see the Perspective by Linke) show how this limiting efficiency can be beaten with a coherent heat source...

This study was conducted in an attempt to characterize some of the effects of sublethal microwave radiation on cells of Staphylococcus aureus. Cultures were exposed to microwave radiation for 10, 20, 30, and 40 s. The effects of a conventional heat treatment were also compared by placing flasks containing cultures in a boiling water bath for the amount of time required to reach temperatures equ...

in this work, a thermal energy storage system was designed and equipped with measuring instruments to study heat transfer characteristics and energy storage and release. in this system, a cubic container which is made of plexiglass was filled with dodecanoic acid as a phase change material. in order to transfer heat to the storage container, a constant temperature heat exchanger was designed an...