The Department of Energy is studying alternative heat pumping technologies to identify possible cost effective alternatives to electric driven vapor compression heat pumps, air conditioners, and chillers that could help reduce C02 emissions. Over thirty different technologies are being considered including: engine driven systems, fuel cell powered systems, and alternative cycles. Results presen...

Improving the efficiency of room air conditioners (RACs) could provide significant energy and associated emissions savings, particularly in emerging economies with hot climates where cooling demand is expected to increase dramatically. To help accelerate improvements, this study identifies “best-in-class” high-efficiency RAC components products. The findings show that manufacturers tend minimiz...

Fluorinated gases (F-gases) used as refrigerants in air conditioners have a significant global warming effect, so their release into the atmosphere must be minimized. The purpose of this study was to evaluate and compare environmental impact two treatment methods: reclamation destruction after refrigerant recovery. Plant data for R410A, R32, R134a, R22 were collected from Japan Europe evaluated...

Models for unitary air conditioners and heat pumps typically have difficulties in providing accurate predictions for the following situations: 1) charge modeling over a large range of charge levels, 2) two-phase refrigerant entering fixed-orifice expansion devices, 3) two-phase refrigerant entering compressors, and 4) non-uniform refrigerant mass flow allocation among evaporator circuits at low...

This study examined the antimicrobial/antifungal ability of a tissue conditioner containing a photocatalyst for Escherichia coli, Streptococcus mutans, Staphylococcus aureus and Candida albicans. The photocatalyst was mixed with tissue conditioners powders at concentrations of 0, 10, 15, and 20 wt%. Tissue conditioners powders containing a photocatalyst were mixed with liquid to make test speci...

The success of a complete denture depends on the fit of the denture, occlusion, esthetics, and other factors. A poorly fitting denture, irritation and other discomforts currently are treated by dentists with the use of tissue conditioners and soft liners.i-3 It is desirable for tissue conditioners to adapt to the oral mucosa as it heals and also to absorb stresses during mastication. Soft liner...