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The efficiency of many of conversion-processes in petroleum and industrial improves upon application of materials with the nanosized scale dimension, which is caused by enhancements and advances of improved properties as the particle size decreases. Nickel nanoparticles has numerous applications in petroleum industry with its own catalytic in additional to the magnetic properties. In this study, high purity nanosized magnetic nickel particles has been effectively prepared by chemical reduction of nickel chloride using hydrazine hydrate as reducing agent in aqueous solutions containing ethylene glycol and water and using polyvinylpyrrolidone (PVP) as anti-agglomeration agent. Nanosized Ni particles samples with different hydrazine to nickel chloride mole ratios and PVP to nickel chloride ratios were obtained at constant temperature of 80 °C. The morphology and structural properties of the produced magnetic nickel nanoparticles were characterized by powder XRD and AFM methods. XRD study revealed that the prepared nanoparticles were pure nickel nanoparticles without considerable oxides or other impurity phases. AFM test revealed that all prepared Ni nanoparticles was in nano scale, it was stated that Ni nanoparticles size was very affected by the hydrazine/nickel mole ratio. Experimental results showed that particle size decreases from 94.35 nm to 71.48 nm when increases the [N2H4]/[Ni2+] molar ratio from 15:1 to 45:1.

Chlorodifluoromethane  is used as pure or in mixture for refrigeration (medium-high temperatures). It is also used as a blowing agent for extruded polystyrene and polyurethane foams and a component in sterilant gas mixtures. A new generalized correlation for the physical and psychometric properties of liquid Chlorodifluromethane as a function to temperature are introduced, Equation (1). The new correlation was statistically compared with those previously presented and found to be :           … (1) Where : A, B, C and D are the property constants, T is the temperature in degrees centigrade.