Materials Science and Engineering

This work was centered on investigating the influence of mercerization treatment of sisal fiber on the mechanical
properties of reinforced polypropylene (PP) composites and modeling of the mechanical properties. The sisal fiber was
sourced from their plantation and was extracted by soil retting process. The extracted fibers were divided into three from
where two parts were subjected to mercerization treatment with sodium hydroxide (NaOH) and potassium hydroxide (KOH)
in a shaker water bath at 50oC for 4 hours respectively. The third part was left as untreated fibers. Both the treated and
untreated fibers were cut into 10 mm lengths and were used for the production of the composites. The fibers and the
polypropylene were blended in predetermined proportions in a randomly dispersed mode and were subjected to heat and
pressure in a heating compression molding machine maintained at 170 oC for 10 minutes. Tensile and flexural properties were observed from universal testing machine and a mathematical response surface methodology model (RSM) was developed. From the flexural and tensile results, it was observed that, KOH treated sisal fiber reinforced polypropylene composites gave the best flexural and tensile properties when compared to NaOH treated sisal fiber reinforced polypropylene composites and untreated sisal fiber reinforced polypropylene composites. The developed RSM models reveal high degree of correlation between the experimental values and the predicted values. This implies that, the model can be used to predict the mechanical properties of the sisal fiber reinforced polypropylene composite materials.

steel tend to have corrosion properties, which is a chemical phenomenon occurs due to the reaction into ions on metal surfaces in contact directly with the aqueous environment and oxygen. Corrosion of reinforcing steel is chemical or electrochemical reaction between the steel reinforcement with the environment.
The title of this paper is "Determine the cause of corrosion In Reinforced Concrete Structures" which aims to explain the concept of corrosion of steel and concrete damage, and how to prevent corrosion in reinforced concrete structures.
The research method using case study, with the literature study instrument. Systematic of writing starts from the First chapter Introduction, including: background, problem, the purpose of writing, and the benefits of writing. Followed Second makes review of the literature, The Third Chapter makes analysis and systematic, and the fourth chapter contains conclusions and recommendations.
The conclusion of this paper is corroded reinforcing steel, which is the beginning of concrete deterioration, which overall will shorten the life of the construction, The process of corrosion of reinforcing steel in concrete occurs carbonation, degradation by sulfate and chloride. Circle of corrosion in reinforced concrete cracked and broken concrete result (construction destroyed) and causes the most dangerous is the sea water and groundwater because it contains sulfate ions.
How to prevent corrosion can be done in various ways: Coating, Chatodic protection, Make alloy or metal alloy that is resistant to rust, Tin plating, Galvanization, Cromium Plating, Sacrifical Protection, and lubrication with oil and grease.

This paper centered on the effects of alkali treatments of sponge fiber (luffa cylindrica) on mechanical and water absorption properties of reinforced polypropylene composites. The sponge fiber was obtained from the plantation and extracted by mechanical decortication. The strands were washed and sun dried before cutting into 10 mm lengths. Alkali treatments were carried out on the sponge fiber using NaOH and KOH respectively. This was done by immersing the fibers in different beakers containing solutions of 1 M NaOH and 1 M KOH, conditioned for 4 hours at 50 0C in a shaking water bath. The composites were produced by dispersing the fibers randomly in the polypropylene before it was fabricated in a heating compression molding machine where the composite was produced. Representative samples were produced for the various fiber contents of; 2, 4, 6, 8 and 10 wt%. Tensile and flexural properties were observed from universal testing machine while water absorption test was carried out on the samples for 7 day. It was deduced from the results, that both treatments can be used to improve the mechanical and water absorption properties of the homopolymer polypropylene matrix by incorporating 2-6 wt% of NaOH treated sponge fiber and 10 wt% of KOH sponge fiber reinforcements respectively.

We present a graphene plasma doping method using chlorine radicals generated in an inductively coupled plasma (ICP) with a
double mesh grid system. Raman spectroscopy and sheet resistance measurement showed that this doping method is non-destructive and controllable approach for the p-type graphene layer doping method. And, by using a chlorine trap-doping method, the sheet resistance could be decreased to 76% at an optimized condition for the tri-layer graphene

This study focuses on the development of epoxy/luffa composites and the investigation of their mechanical and acoustical properties. The fibers underwent an alkalization treatment, and its effects on the mechanical and sound absorption properties of the composites were measured utilizing a universal testing machine and two-microphone transfer function impedance tube methods. The effects of chemical modifications on the fibers were studied using a scanning electron microscope (SEM). The thermal analyses of composites were conducted using thermo-gravimetric analysis (TGA). The composite’s functional group was identified and evaluated using Fourier transform infrared spectroscopy (FTIR). The sound absorption coefficient of untreated and treated composites across a range of frequencies was very similar. Untreated composites appeared to perform better than those that were treated. Compared with untreated fiber composites, there was an improvement in the tensile strength of the treated fiber composites. The SEM characterization showed that the alkaline treatment changed the morphology of the fibers, resulting in a decrease in the sound absorption coefficients of the composites. The thermal characterization of composites showed that dehydration and degradation of lignin occurred in a temperature range of 40 to 260 °C, and the maximum percentage of cellulose was found to decompose at 380 °C.

The development of the polymer gel dosimeter evaluation focused mainly on magnetic resonance
imaging (MRI) techniques. A new alternative imaging technique which is x-ray CT imaging has emerged from a
current research. The study focused on the dose response, the dose sensitivity and the accuracy of the MAGAT gel
dosimeter using two different imaging modalities. The MAGAT gel dosimeter was irradiated at 1, 5 and 10 Gy 24-h
post-manufacturing. The imaging of MAGAT gel dosimeter by MRI and x-ray CT were done a day post-irradiation
using an optimized protocol. The dose sensitivity of the gel obtained by the MRI technique was 0.7157 s-1Gy-1, whereas
the dose sensitivity obtained by the x-ray CT technique was 0.6177 HGy-1.

Rouging, which describes the presence of a surface layer of iron oxide, is a phenomenon that often affects pharmaceutical and hospital water systems constructed from stainless components. Rouging presents a particular risk to high-purity water systems, such as Water-for-Injections or Purified Water (produced by either distillation or reverse osmosis.)

The risk that arises from rouging is that product contamination, through the presence of particulates, could occur. To add to this, there is an impact on water quality for rouge may be the source of contaminants that lead to the chemical deterioration of water quality. Furthermore, buildups of rouge byproducts can lead to operational problems including blockages in filters. If more severe localized corrosion (pitting) occurs, this can lead to more serious operational issues.