Synthesis and Characterization of Alumina-ChitosanHydroxyapatite Biocomposites for Load Bearing Application

This study investigated the influence of reinforcing hydroxyapatite (HA) with alumina (Al) and chitosan nanofiber (CH) to enhance its usefulness in load bearing application. Commercial alumina was used while chitosan fiber and hydroxyapatite were synthesized from cowry shells and limestone respectively. The developed composites were characterized with a view to assessing theirsuitability for use as medical implants in load bearing capacity. It was observed that the optimum compressive strength obtained was 181.73 MPa, tensile strength of 172.67 MPa, hardness value of 529.21 HV, fracture toughness of 7.42 MPa.m1/2 , elastic modulus of 8.23 GPa and bending strength of 175.51 MPa. Increasing volume fractions of Al-CH resulted in decrease in compressive strength, hardness and elastic modulus of hydroxyapatite while its tensile strength, bending strength and fracture toughness increased. The result obtained from the Fourier Transform Infrared Spectrometry revealed that the intermolecular hydrogen bond and chelate interaction between the constituents contribute to the good mechanical properties of the composite. X-Ray Fluorescence analysis result indicates that their chemical compositions contain ions which are found in the physiological environment. The dispersion of the alumina-chitosan nano fiber in the HA matrix as revealed by the Scanning Electron Microscope micrographs result in the formation of interfaces which activates different mechanisms that improve the strength of HA. The optimum mechanical property was obtained at 20-20-60 Al-CH-HA composite. Hence, this composite will be a suitable material for load bearing application

The influence of aluminium metal matrix composite reinforcement - A mini review

The joined influence of fortifying metal matrix composites with separate and numerous particle reinforcing agents like hybrid metal matrix composites are utilized greatly in the manufacturing industry. This is attributed to the enriched mechanical and wears characteristics such as strength, impact and wear resistance. In the present study, a series of research undertakings were carried out. This paper directs the technologists and scientists towards the appropriate collection of materials by their constituents in the field of study and diverse methods used in the fabrication of metal matrix composites, especially on the metallurgical stir casting process

Advancement in engineering materials and the growing concern

Corrosion has been and still the world's worst nightmare which costs hundreds and thousands of dollars for companies to maintain their equipment and repairs. Studies are being done all around the world to create the solution toward preventing the corrosion by surface engineering technology. One of the simplest and most cost effective methods to provide thin film coating for advance application is through electrolytic deposition route. Thus this review looks into the advances of materials and corrosion challenges

Synthesis and Characterization of Cowry and Crab Shells Based Chitosan for Drug Delivery

This work aims to synthesize chitosan from locally available cowry and crab shells for Pharmaceutical application in drug delivery. Chitosan was synthesized from both shells using standard deacetylation technique. The synthesized chitosan, piroxicam and lactose were employed in preparing the drug loaded tablets by direct compression technique and subjected to characterization with the aid of Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Spectroscopy (SEM) and optical microscopy. Finally, the drug release rate was investigated with in vitro drug dissolution test. The results of FTIR spectra confirmed that the biopolymer extract was chitosan and it also shows that there was no interaction between chitosan and the piroxicam. The morphological properties of the samples were found to be suitable for drug delivery. The applied load and composition of tablets influenced the drug release rate

Experimental studies and influence of process factor on zinc-nickel based coating on mild steel

Sulphate-rich electrolytic bath containing ZnSO4.7H2O in NiP solution was used to develop coating with Ni-P-Zn matrix under optimised process parameter. The major considerations are to examine the factor variance and the effect of varying time parameter between 10, 15, 20 and 25 min on the developed coating. Wear loss evolution was examined using reciprocating sliding wear tester with a force of 10 N and 20 N. The microhardness behaviour was examined using durascan microhardness tester with diamond indenter. The change in the structural build-up and the corrosion performance trend was observed using a scanning electron microscope enhanced with energy dispersive spectroscopy and potentiodynamic polarisation route. From the result we observe that time-dependant factors impact maximally on the crystal growth which rightly influences the coating hardness performance. For wear performance, the counter with external forces couldn’t penetrate wholly into the lattice of the developed coating due to the resilient formation of stable flakes. The microstructure formation shows stable dispersed crystal build-up and homogeneous growth. An excellent corrosion resistance characteristic was noticed with Ni-P-Zn-25 min matrix

A Review on Corrosion in Concrete Structure: Inhibiting Admixtures and Their Compatibility in Concrete

The development in marine industry and its effort in building bridges has placed a huge demand on reliability and duration of service of reinforcing steel in concrete. Literature has documented several studies on corrosion of reinforcing steel in concrete induced via carbonation and chloride in marine milieus. Extension of concrete structures service life has been one of the foremost strong worries of the concrete industry, especially for marine industry. Hence, the necessity to employ a cost effect system for shielding the reinforced steel in concrete from corrosion. Studies have shown that one prospective solution in combating corrosion deterioration in reinforced steel in concrete structures is the introduction of corrosion-inhibiting admixtures into concrete. This review discussed at length corrosion in reinforced concrete and corrosion inhibitors in relation to concrete together with the classification of inhibitors based on the method of applications. This review further reports corrosion-inhibiting admixtures in concrete. As a result, the aspects of corrosion inhibitors this manuscript reviewed are corrosion inhibitors employed as admixtures in concrete for new construction in the marine industry. Furthermore, corrosion inhibitors are employed for repairs and maintenances admixed with concrete for patches on marine structures, squirted onto the surface of the concrete or put on the concrete surface via saturation treatment. As a result of the excellent properties of functional nanostructured materials, the advancement in the implementation of functional materials in inhibiting admixtures in concrete is fast growing in marine industry. Hence, the Integration of functional materials in inhibiting admixture and their compatibility were reviewed. The significance of inhibitors employed as admixtures in concrete for practical applications of corrosion are the suppression or mitigation of corrosion process of metals used in marine industry and the patches of already constructed structures. The current problems related to corrosion-inhibiting admixtures in concrete and the future research and development directions were discussed

Utilization of Waste Materials for Eco-Friendly Building Ceilings: An Overview

The pioneers of the industrial revolution, and their successors, left the world’s ecosystem in a devastating state. Global warming became the consequence of activities in the industry that led to climate change, the depletion of the ozone layer, and pollution of the ecosystem. For decades now, concerned researchers have been frantically investigating methods and procedures that can help conserve the ecosystem's left to attain sustainability. The construction industry also poses its challenge as novel solutions to construct sustainable, less hazardous products to the environment and improve human health are diligently investigated and identified yearly. This paper discusses specific steps of this nature and explains how environmentally-friendly construction methods and materials produce ceiling boards

A Review on Corrosion in Concrete Structure: Inhibiting Admixtures and Their Compatibility in Concrete

The development in marine industry and its effort in building bridges has placed a huge demand on reliability and duration of service of reinforcing steel in concrete. Literature has documented several studies on corrosion of reinforcing steel in concrete induced via carbonation and chloride in marine milieus. Extension of concrete structures service life has been one of the foremost strong worries of the concrete industry, especially for marine industry. Hence, the necessity to employ a cost effect system for shielding the reinforced steel in concrete from corrosion. Studies have shown that one prospective solution in combating corrosion deterioration in reinforced steel in concrete structures is the introduction of corrosion-inhibiting admixtures into concrete. This review discussed at length corrosion in reinforced concrete and corrosion inhibitors in relation to concrete together with the classification of inhibitors based on the method of applications. This review further reports corrosion-inhibiting admixtures in concrete. As a result, the aspects of corrosion inhibitors this manuscript reviewed are corrosion inhibitors employed as admixtures in concrete for new construction in the marine industry. Furthermore, corrosion inhibitors are employed for repairs and maintenances admixed with concrete for patches on marine structures, squirted onto the surface of the concrete or put on the concrete surface via saturation treatment. As a result of the excellent properties of functional nanostructured materials, the advancement in the implementation of functional materials in inhibiting admixtures in concrete is fast growing in marine industry. Hence, the Integration of functional materials in inhibiting admixture and their compatibility were reviewed. The significance of inhibitors employed as admixtures in concrete for practical applications of corrosion are the suppression or mitigation of corrosion process of metals used in marine industry and the patches of already constructed structures. The current problems related to corrosion-inhibiting admixtures in concrete and the future research and development directions were discussed

Thermal-emission assessment of building ceilings from agro-industrial wastes

Most of the building ceiling tiles used today from studies, such as polyvinyl chloride (PVC) composite ceilings, cardboard, plywood, particleboard, are flame friendly. Except for asbestos, which is confirmed to emit asbestosis, cancer from asbestos; already warned by the Environmental Protection Agencies and other health standard organizations. Studies have shown inherent harmful elements associated with the use of PVC Ceiling composite, plant-based ceiling, and asbestos, which propagate noxious emission at the instance of fire; their widespread use is quite enormous. The noxious behaviour during an inferno is a representation of the elemental make-up of these ceiling materials. Moreover, their vulnerability due to emission and combustion threat call for alternative materials with eco-friendly constituents for building ceiling applications. Problems associated with these building ceilings during fire include noxious gaseous emissions; fuel for the flame from ignition from other roof frame structures; after flame effect of inhaling poisonous gasses against the recommended exposure limit of 35 ppm by the World Health Organization (WHO). Flame retardance is credited to asbestos. However, for other ceiling tiles, some of the challenges of high heat flux, high thermal conductivity, and combustibility tendencies, are still current issues. The undesirable side effects of using ceiling tiles have necessitated a replacement with suitable flame retardant and eco-friendly influences. This is made to bear by appropriate material selection and by employing industrial wastes and agricultural wastes coupled with suitable binders to solve flame propagation challenges. It is, therefore, necessary to develop a flame retardant ceiling composite that will solve the identified anomalies in the existing ceiling tiles in the market in building industries. The developed materials are tested for thermal and emission characteristics to ascertain their integrity by employing advanced test equipment. The result shows that there are low values in thermal conductivity of the developed building ceiling samples. Sample 2 has the lowest value compared to the developed and existing ceiling tiles, much < 0.0802 W/mK, which is a desirable property in ceiling application. Low thermal diffusivity is required to suppress flame propagation. This is exhibited by sample 1, with a value of 0.85 × 10−8 m2/s as the lowest amongst developed ceiling samples The result showed null and negligible SO2 detection for all samples. The three samples' time to attain pre-set temperature varies in the ascending order of sample 1 at 24 min, sample 3 at 37 min, and sample 2 at 42 min. Sample 3, 0.6Aldr0.34Cmt0.05G0.01OBS; Sample 2, 0.6Aldr0.32Cmt0.05G0.03OBS and sample 1, 0.6Aldr0.3Cmt0.05G0.05OBS are in the order in terms of safe emission characteristics while sample 2 ranks best in terms of flame retardancy. This study has established that the developed building ceiling composite material is flame retardant capable of preventing fire propagation, unlike the flammable polyvinyl chloride (PVC) ceiling composite. The developed building ceiling composite can minimize the emission of harmful elements in the make-up of the ceiling, as revealed in the results. The tiles are alternative to both noxious PVC and asbestos ceiling tiles. Oil beanstalk is a novel material introduced as a reinforcement to the developed composite. The manufacturing industries should explore materials with excellent eco-friendly flame retardant constituents to encourage sustainable building production. PVCpolyvinyl chlorideWHOWorld Health OrganizationOBSOil Bean StalkCmtCementAldrAluminium drossCSHcalcium silicate hydrateCASHcalcium Aluminium silicate hydrateSEMScanning Electron MicroscopeEDSEnergy Dispersive SpecroscopyGCarbon Graphit