Hand-lay up method was used to prepare the samples made of epoxy (EP) as a matrix reinforced with chopped carbon fibers (CCF). The fatigue behavior of epoxy resin /chopped carbon fiber composites was studied with different weight percentage of chopped carbon fibers (2.5%,5%,7.5%,10%,12.5%). The fatigue test was carried out under alternate bending method, which was made by applying sinusoidal wave with constant displacement (15mm), stress ratio R=-1,and loading frequency 10Hz, which is believed to give a negligible temperature rise during the test. The results of the maximum stress, fatigue strength, fatigue limit and fatigue life of the tested composites are calculated from stress(S)-number of cycles(N) (S-N) curves.
It was shown that increasing weight percentage of chopped carbon fibers increase the values of maximum stress for all composites, while the values of fatigue strength, fatigue limit and fatigue life increasing for all composites except the composite with reinforcing weight 12.5%, which was subjected to rapid failure (fracture). This failure could be due to the debonding of the chopped carbon fibers from the matrix epoxy.
Granulation Technique for Gamma Alumina Catalyst Support was employed in inclined disk granulator (IDG), rotary drum granulator (RD) and extrusion – spheronization equipments .Product with wide size range can be produced with only few parameters like rpm of equipment, ratio of binder and angle of inclination. The investigation was conducted for determination the optimum operating conditions in the three above different granulation equipments.
Results reveal that the optimum operating conditions to get maximum granulation occurred at ( speed: 31rpm , Inclination:420 , binder ratio:225,300% ) for the IDG,( speed: 68rpm , Inclination: 12.50 , binder ratio: 300% ) for the RD and ( speed:1200rpm , time of rotation: 1-2min )for the Caleva
Self- curing is the potential of lightweight aggregate to absorption great amount of water thru mixing which prominently can moves to the paste during hydration process. Self- curing empowers a water to be distributes more evenly act out the cross section. Whereas, the external curing water is only able to penetrate several millimetres into concrete with low water cement ratio. Brick dust accumulates in the demolish site creates serious environmental contamination. This study investigates the effect of brick dust recovered from construction site on the Properties of mortar cured in three curing conditions. Mortar in this study produced using BD as cement additive with (2, 4, 6, and 8) % by weight of cement. BD was used a
... Show MoreAeromonas hydrophila have been isolated as a cause of a cute gastroenteritis in 23 (5.6%) of 410 patients. Other bacterial enteropathogens have been isolated from 387 patients with diarrhea, were 19 different strains. A. hydrophila occurred more commonly in children with acute diarrhea, the results showed that 18(78.26%) isolates of A. hydrophila found in children under 10 years old ,distributed to 10(43.47%) in male and 8(34.78%) in female ,and in adults with diarrhea 5 (21.73%). In the other hand, we noticed frequency of isolation was higher in male 14(60.86%) when compared with 9(39.14%) in female. Six strains of A. hydrophila have been observed to have bacteriocin activity against 12 of 23 different A. hydrophila ,as well as Staphy
... Show MoreMedicinal plants contain bioactive substances that are highly bioavailable in extracts or pure molecules, making them promising for therapeutic applications and precursors for chemo-pharmaceutical semi-synthesis. Harpagophytum procumbens (Devil’s Claw) is widely recognized as one of the most potent therapeutic herbs. This study aimed to extract seeds from H. procumbens using two types of solvents and to assess both qualitative and quantitative aspects of the extracts. The two extracts were evaluated for antibacterial and anti-biofilm activities using agar well diffusion assays against four bacterial isolates and two yeast isolates. Qualitative analysis identified the presence of alkaloids, flavonoids, tannins, saponins, and terpen
... Show MoreAs cultures are mainly divided into collectivistic and individualistic, members tend to emphasize, through communication, either their position as part of their group or their independence from the group. This emphasis is manifested in using the pragmatic concepts of positive politeness and negative politeness. The present study looks into the reflection of these two cultures in Rockstar’s renowned video game, Red Dead Redemption 2 (2018). It aims at identifying the two cultures as present in the game and showing their significance to its narrative. It fills the gap in the studies of language used within video games as well as its cultural reflections. The study addresses the following question: What are the positive and negative
... Show More