The problem of microbial resistance continues to increase in all regions of the world, and even though a very large number of antibiotics have been produced in the last 30 years, microbial resistance is maintained because of the wide use of these drugs against many infectious diseases. Thus, natural products are seen as the alternative solution. Based on previous studies, Peganum harmala has been reported to exhibit several biological properties including antibacterial and antifungal. Thus, the main aim of this study is evaluating antibacterial activities of P. harmala against Escherichia coli, Klebsiella pneumoniae and Staphylococcus aureus, which isolated from infected patients in (Alassaba'a hospital, Alassaba'a, west of Tripoli). Agar disk diffusion technique was used for detecting the antibacterial activity, and the minimum inhibitory concentration was tested by serial dilution methods. The results showed that the growth of all tested bacteria were inhibited strongly by methanol extract of seeds at 1.0% with inhibition zones 14.66, 12.00 and 15.33mm against E. coli, k. pneumoniae and S. aureus respectively. Besides, MIC values ranged between 0.625 to 1.25 mg/mL. While, MBC values ranging between 1.25 to 5 mg/mL. On the other hand, methanol extract of leaves was also inhibit the growth of E. coli, k. pneumoniae and S. aureus with inhibition zones 11.00, 9.66 and 10.00mm respectively. As well as, MIC values ranging between 1.25 to 2.5 mg/mL, while MBCs value ranging between 2.5 to 5 mg/mL . In conclusion, methanol extract of P. harmala seeds exhibited strongly antimicrobial activity against E. coli, k. pneumoniae and S. aureus, thus it can be developed as anti-bacterial agent.

The present study was carried out to evaluate the fluoride content of bottled water brands available in the market of Tripoli city and to measure if it is consistent with local standards. A total of 23 commercially available brands were collected and examined for fluoride content. 22 samples were locally produced and one was imported. The average fluoride levels of each sample was determined using the procedure outline in the Palintest photometer method and then compared with the fluoride content printed on the bottle labels. In all bottled water brands investigated, 19 brands of the analyzed samples did not state the fluoride levels on the labels of the bottles. The determined fluoride concentrations ranged from 0 to 2.75 ppm. For each brand, the fluoride level was not similar to the labeled fluoride. 82.6% (19 brands) had a fluoride content lower than the Libyan standards, 1 brands had a fluoride content higher than the Libyan standards, and 7 brands had zero fluoride content. All the samples examined had fluoride content outside the range regulated by Libyan standards. There was a significant variation between the F levels stated by the manufacturer on the bottle labels and the values measured during the investigation

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Abstract  

In some engineering applications soil stiffness only could not be a reliable parameter in accordance with specific standardizations especially, when

dealing with dynamic loading. In other words, foundation soil should be altered regarding its ductility in order to prevent sudden damage due to brittleness. Plenty of researchers have studied the effect of multifilament polypropylene fibers on soil reinforcement. Besides, the alkaline activation method has been adapted to alter the strength properties of soft soil. Furthermore, in a cutting edge method, alkaline activation of soft soil, using fly ash and Potassium hydroxide, coupled with soil reinforcement was adapted to change the post-peak behavior of soft soil. The goal of this novel technique is to increase the ultimate strength and to enhance the failure mode. In this research work alkali activated kaolin soil and alkali-activated reinforced kaolin soil were cured for 28 and 90 days respectively. Compressive stress tests were conducted on both mixtures, namely, SF40 ( Soil +40% fly ash) and SFR0.75 ( Soil+ 39.7% fly ash + 0.75% PP fibers) samples. Results drawn from the tests revealed a drastic increase in Compressive strength for SF40 samples cured for 28 and 90 days, namely, 3680 kPa and 18500 kPa, respectively. Whereas, the strength recorded by the control sample was only 190 kPa. Though a sharp drop was seen when approaching failure. The addition of reinforcing Polypropylene fibers brought about a drastic enhancement in failure mode for both of curing regimes.

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Biosynthesis techniques have a number of advantages over other methods for producing silver nanoparticles (AgNPs), which provide a wide range of applications. The present work highlights the biosynthesis of AgNPs by mixing pear leaf aqueous extract with silver nitrate, and the formation of AgNPs was observed by the change of mixture color from yellow to dark brown and visible spectrophotometry. Moreover, the effect of pH, reaction time, AgNO3 concentration, extract volume and temperature on the suggested approach was also studied. The results showed that pear leaf aqueous extract is an excellent material for the biosynthesis of AgNPs, and by controlling the mentioned parameters that influence synthesis, a large number of AgNPs with small sizes may be produced. Keywords: silver nitrate, silver nanoparticles, pear leaves, biosynthesis 

Biosynthesis techniques have a number of advantages over other methods for producing silver nanoparticles (AgNPs), which provide a wide range of applications. The present work highlights the biosynthesis of AgNPs by mixing pear leaf aqueous extract with silver nitrate, and the formation of AgNPs was observed by the change of mixture color from yellow to dark brown and visible spectrophotometry. Moreover, the effect of pH, reaction time, AgNO3 concentration, extract volume and temperature on the suggested approach was also studied. The results showed that pear leaf aqueous extract is an excellent material for the biosynthesis of AgNPs, and by controlling the mentioned parameters that influence synthesis, a large number of AgNPs with small sizes may be produced.