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Production of Spindle Palm Petiole Fiber Reinforced High Density Polyethyele Composites

100%

Nneka E. L. , Monday O. , Nnaemeka O. B. , Uzoma E. R.

World News of Natural Sciences

2021

tom 38

98-119

The work is on the production of spindle palm petiole fiber reinforced high density polyethylene (HDPE) composites. The Spindle Palm Petiole Fiber (SPPF) and HDPE composites were produced using injection molding machine. SPPF were characterized to determine their chemical compositions. Central Composite Design (CCD) was applied as an optimization tool of RSM for cellulose and tensile strength. The chemical composition of the SPPF is cellulose (65%), hemicelluloses (17.1%) and lignin (14.1%). Surface modifications of the fiber enhanced the properties of the fiber. Quadratic model adequately described the relationship between percentage cellulose yield and variables: chemical concentration, mass/volume ratio and time. The cellulose content at optimal level is 60.3% at 3.5wt% concentration, 4g/l mass/volume ratio and time of 16hr. Also for the composite, the quadratic model described the relationship between tensile strength and temperature, fiber/polymer ratio and time. The optimum tensile strength of 42.0 Mpa was obtained at fiber/polymer ratio of 29wt%, temperature of 172 °C and time of 10 min. Water absorbed by the untreated fiber was high compared to the chemically treated fiber. The chemical treatment created a better interfacial bonding of SPPF/HDPE and this could be responsible for the observations.

Gravimetric study of corrosion inhibition of mild steel in H2SO4 environment using watermelon (Citrullus lanatus (Thunb.) Matsum. & Nakai) leaf extract as inhibitor

88%

Monday O. , Tony G. B. , Okorie O. , Azuka E. J. , Ogechukwu A. S.

World News of Natural Sciences

2024

tom 53

17-31

ABSTRACT This work presents gravimetric study of corrosion inhibition of mild steel in H2SO4 environment using watermelon (Citrullus lanatus) leaf extract as inhibitor. The extract was characterized in terms of phytochemical status and functional groups. Its efficiency in the corrosion inhibition was optimized using response surface methodology (RSM). In the RSM, interactive effects of inhibitor concentration, temperature and time on the efficiency of the extract were monitored using central composite design of design expert software. Analysis of the results show that watermelon leaf extract successfully inhibited corrosion of mild steel in H2SO4 environment. Predominant functional groups of watermelon leaf include; C-H stretch (2851.4 cm-1), N-H symmetric and asymmetric stretch (3267.7 cm-1), C=H stretch (2195.4 cm-1), =C-O-C stretch (1241.2 cm-1), C=O symmetric and asymmetric stretch (17722.0 cm-1), C-F (1155.5 cm-1) and =C-H bend (674.0 cm-1). It contains polar atoms of nitrogen and oxygen. Its major phytochemicals are alkaloids (243.14 ±0.03 mg/100g) and tannins (216.32 ±0.02 mg/100g). The extract possesses good inhibitive properties. Weight loss, corrosion rate, inhibition efficiency and degree of surface coverage were influenced by time of immersion of the mild steel, temperature and concentration. The watermelon leaf extract exhibited high inhibition efficiency. Hence, it can be used to inhibit corrosion of mild steel in H2SO4 solution. Quadratic equation reliably connects the inhibition efficiency with the considered factors. Optimum Inhibition efficiency of 92.96% was attained by the watermelon leaf extract.

Optimization of protein content of fish feed formulated using compositions of groundnut cake, milk powder, lemon grass and corn cob

88%

Monday O. , Amaoge O.-O. I. , Ejike I. F. , Okorafor-Nwosu A. E. , Dymphna N. N.

World News of Natural Sciences

2024

tom 57

170-186

This work presents the optimization of protein content of fish feed formulated using compositions of groundnut cake, milk powder, lemon grass and corn cob. The ingredients (precursors of the feed) were characterized in terms of proximate analysis, and they were used for the formulation fish feed. Functional groups of the feed were ascertained using Fourier transform infrared spectroscopy. The protein content of the feed was optimized using response surface methodology. From the analyses of the results, ash contents of 2.78 %, 6.74%, 3.53%, and 4.91% were recorded for groundnut cake, milk powder, lemon grass and corn cob respectively. It indicates high content of minerals. Also, there high protein contents, 21.69%, 35.13%, 31.02% and 3.40% for groundnut cake, milk powder, lemon grass and corn cob samples respectively, which show that the samples are suitable for the fish feed formulation. The major functional groups of the fish feed are; C-H stretch, O-H stretch, N-H symmetric, C-H stretch, ≡C-H stretch, N-H bend, CH(CH3)2, C-F stretch, C-O-C sym, =C-H bend and C-H bend. It revealed the presence of alkane and alkyls and carboxylic acids. Heteroatoms (O, N) are present in the feed. Quadratic equation represents the relationship between the feed protein content and the compositions of the feed raw materials. The predicted protein content (33.68%) compare significantly with the experimental protein content of 33.88%, with percentage deviation of 0.59% (< 5%). Thus, the feed’s protein content obtained at appropriate quantities of groundnut cake, milk powder, lemon grass and corn cob was successfully optimized.