This paper presents environment friendly refrigerant R290 as a solution to the environmental concerns like depletion of ozone layer and rise in global warming because of wide use of synthetic refrigerants R22 and R134a. The water cooler is the widely used refrigeration application in warm climatic countries. Refrigerant R22 and R134a are predominantly used refrigerants in water cooler refrigera...

This paper presents the results of a study random copolyethersulfone sulfides based on 4,4-dichlorodiphenylsulfone, 1,1-dichloro-2,2-di(4-hydroxyphenyl)ethylene, and sodium sulfide. The synthesis with different ratios polyethersulfone polyphenylenesulfone sulfide units was carried out by high-temperature polycondensation reaction nucleophilic substitution in N,N-dimethylacetamide medium using p...

Non-halogenated “all-in-one” flame retardant HDPE.

A new processing protocol based on non-halogenated solvent and additive is developed to produce polymer solar cells with power conversion efficiencies better than those processed from commonly used halogenated solvent-additive pair. Morphology studies show that good performance correlates with a finely distributed nanomorphology with a well-defined polymer fibril network structure, which leads ...

Antibodies against cytochromes P-450a, P-450b + P450e, P-450c, and P-450d and epoxide hydrolase were utilized in a radial immunodiffusion assay to measure the concentration of these inducible, xenobiotic-metabolizing enzymes in liver microsomes from rats treated with Aroclor 1254, fireMaster BP-6, or one of 41 individual polychlorinated and polybrominated biphenyl isomers and congeners. Cy...

This paper describes the development of a computer simulation model of an integrated supermarket refrigeration and heating system using natural refrigerants (namely ammonia and hydrocarbons). Initial resultS of the model's performance are presented, showing the influence of some of the operating parameters on system thermal efficiency. This will be validated using data collected from monitoring...

This paper presents an analytical evaluation of isobutane (R600a), propane (R290), R134a, R22, R410A, and R32 in a vapor compression system used for comfort cooling applications. The evaluation method was based on a system simulation model that was complimented with an evolutionary computation module for the optimization of refrigerant circuitries in the evaporator and condenser. The evaluation...

This review presents the nucleate/convective boiling performance for a variety of important low global warming potential (LGWP) alternatives to commonly used high-global (GWP) refrigerants (such as R-134a, R404A, and R-410A, etc.). Efforts are stressed on assessment their evaporation pressure drop heat transfer coefficient (HTC) characteristics. These include R-1234ze(Z), R-1234ze(E), R-1233zd ...

Prediction methods to evaluate liquid dynamic viscosity and thermal conductivity along the saturation line are presented in this paper for pure and mixed refrigerants. The thermal conductivity correlation presented here is an extension to the new refrigerants of an equation previously proposed by one of the authors. The viscosity correlation has been improved upon a previous version in order to...