An investigation was conducted for the improvement of viscosity index of light lubricating oil fraction (40 stock)
obtained from vacuum distillation unit of lube oil plant of Daura Refinery, using solvent extraction process.
In this study furfural solvent was used to extract the undesirable materials which reduce the viscosity index of raw
lubricating oil fraction.
The studied effecting variables of extraction were extraction temperature range from 70 to 110°C, and solvent to oil
ratio range from 1:1 to 4:1 (wt/wt).
The n-d-M method was used for calculation of carbon distribution and structural group analysis of the raffinate
produced from furfural extraction.
Also the three component phase diagram for a mixed-base oil and furfural at different temperature was drawn.
The results of this investigation show that the viscosity index of lubricating oil fraction increases with increasing
extraction temperature and increasing the solvent to oil ratio and reaches 115.6 at extraction temperature 110°C and
solvent to oil ratio 4:1.
Further more, the results show that the viscosity, refractive index, density, sulfur content and percentage yield of
produced raffinate were decreased as the extraction temperature or solvent to oil ratio increases for extraction process.
Helicobacter pylori (H. pylori) is one of the most common human pathogens in the world. Several studies that have investigated the correlation between H. pylori infection and type 2 diabetes mellitus (DM) found that H. pylori infection is more frequent in the patients, while the results of other studies were unclear. This paper aims to investigate the interrelation between the infection with H. pylori and type 2 DM in Dohuk governorate, Iraq. Eighty four diabetes patients (41 males, 43 females) and 92 healthy controls were involved in this study. H. pylori status was assessed in serum samples by using ELISA test. Out of the 84 patients,
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