Abstract: Rheological properties of Gum Habeil collected during three seasons had been studied. Intrinsic viscosity of aqueous solution of Gum Habeil was calculated by Fedor's equation. At a low concentration of aqueous deacetylated gum solution, the G' (viscoelastic) was appeared higher than G'' (viscosity) at frequency ranged from 1 to 10 Hz, but with increases concentration of deacetylated gum solutions G'' line was trend to appear higher than G' line at low frequency region. However, a crossover of G' and G'' lines was observed as the frequencies increased to 1.26, 3.97, and 9.99 Hz for 1.5, 3, and 5% w/w of gum solutions respectively. The concentrated crude gum dispersions 12.5 and 15% w/w were exhibited viscoelastic behavior, in contrast the 10% w/w of crud gum solution in distilled water appeared G'' higher than G' with the crosslink points at the middle of frequency range. The critical concentration C* of deacetylated gum solutions in deionized water, in sodium hydroxide alone, and in alkali with addition salt were determined to be 2.34, 2.37, and 2.41 g/dl respectively. The effect of temperature on rheological behavior was also studied. arabic 8 English 57
Aborawi M. Elgornazi, M. H. Awad, Nouri M. A. Soleiman(2-2020)

Ten vinegar samples were collected from the Libyan local market in the city of Tripoli. The elements have been investigated were:As, Pb, Cu, Fe and Zn. The samples were treated and prepared according to Indian standard IS 14703-1999, and the measurements have been done by using inductively coupled plasm – atomic emission spectroscopy (ICP-AES) available in the Libyan Petroleum Institute. The analysis indicated that the concentration of Arsenic of all the samples was less than 0.02mg/kg whereas, the concentration of lead is less than 0.03mg/kg. The concentration ranges of Cu, Fe and Zn were 0.11-0.59mg/kg, 0.72-2.67mg/kg and 0.08-0.28mg/kg respectively. The concentrations of the elements AS, Pb, Cu, Fe and Zn are within the limits of a variety of standards such as Libyan, Indian and Pakistani ones. arabic 21 English 134
ABUBAKER A BASHIR ATRROG, RAGIAB ALI MOKHTAR ISSA, ِAburawi Mohammed Aburawi Algornazi(11-2020)

The study focused on determining the levels of lead and cadmium in some samples of the best-selling and popular tea and coffee among people in Tripoli city-Libya during the years 2018-2019. Atomic Absorption Spectroscopy (AAS) has been used to determine the concentrate of cadmium and lead ions in different 17 tea samples, and 11 coffee samples. The mean values of cadmium and lead in (mg/kg) in tea samples as follows: The highest value for cadmium was found in Libton tea sample 0.260 ? 0.017, while the lowest value was found in Alkoozi red tea and Alfrdous tea samples 0.037 ? 0.006, with the overall mean was 0.119 ? 0.054. The highest value for lead was found in Alkoozi green tea sample 2.153 ? 0.012, while the lowest value was found in Alzahra tea sample 0.187 ? 0.002, with the overall mean was 1.118 ? 0.612. The results show that there are no significant differences in the values of lead in all coffee samples, which ranged from 1.23 to 1.62 mg/kg with the overall mean was 1.277 ? 0.358, except Sheikh Hbahanbelend coffee sample 0.271? 0.002 mg/kg. While the cadmium concentration in coffee samples ranged from 0.022 to 0.064 mg/kg, with the mean value 0.0514?0.0012. From these results can be noticed that coffee samples have about 11 times higher concentration of cadmium than tea, whereas the concentration of lead in tea is about 22 times higher than that in coffee samples.
ezuldeen mohammed abraheem aboushalloua(1-2022)