Oleo gum resins are plant exudates commonly used in folk medicine for treating several disease
conditions. Anti-cariogenic properties of essential oil (E. oil) and crude extracts obtained from
Boswellia frereana (B. frereana), Boswellia carterii (B. carterii) and Commiphora myrrha
(C. myrrha) were investigated. Methanol and acetone extracts of the three plants inhibited
Streptococcus mutans (S. mutans) and Lactobacillus spp. growth. Hexane extracts showed
low anti-microbial activity. The average microbial inhibition was 14.6 mm for S. mutans and
13.8 mm for Lactobacillus spp. regardless of solvent type. B. frereana produced 8% E. oil
while B. carterii and C. myrrha gave 5% and 6%. B. frereana E. oil inhibited S. mutans and
Lactobacillus spp. more than B. carterii and C. myrrha E. oils.
The use of hybrid composite has increased due to their special mechanical and physical properties.
However, machining of composite materials is extremely difficult due to non-homogeneous,
anisotropic and highly abrasive characteristics. The performance of machined surface quality of
CFRP/Al2024 was described using two level full factorial methodology. Trimming test was performed
under dry conditions using 6mm diameter of burr tools end mills. The factors investigated were spindle
speed(N), feed rate(fr) and depth of cut(dc), furthermore Ra CFRP and Ra Al2024 were the response
variables. This work aims to minimize the machined surface quality of CFRP/Al2024 between 1µm to
2µm. The finding of this empirical study has shown that, the best estimated value of fr should be 500
mm/min to 530 mm/min, N is between and 2313.870 rpm to 2336.042 rpm. For both response spindle
speed is the most significant effect followed by Feed rate and Depth of Cut.