Exploring the biodiesel potentials of waste avocado fruit oil
February 2024
The biodiesel potential of waste avocado fruit was investigated. This study is essential for utilizing the enormous waste generated from avocado cultivation in Nigeria. Biodiesel was produced using a two-step acid-base catalyzed transesterification process. The acid catalyzed esterification step was required to convert the free fatty acids present in the oil to methyl esters. Important biodiesel properties such as flash...
Computational fluid dynamics (CFD) simulation of a gas-solid fluidized bed: Residence time validation study
December 2022
In this work, the business Computational Fluid Dynamics (CFD) is used for the numerical simulations of an air-solid fluidized bed container in the solid phase involving a multi-fluid Eulerian multiphase model and the Kinetic Theory of Granular Flow (KTGF). The height of the fluidized bed setup is 1.5 m while its diameter is 0.2 m. With it, a series of experimentations were obtained using Helium tracer to determine the...
Assessment of the quality of hand dug well used for drinking and agricultural activities at Blama, Small-Bo Chiefdom, Eastern, Sierra Leone
April 2022
This research investigates the microbial and physicochemical characteristics of five local hand dug wells used for drinking and agricultural activities in Blama, Small-Bo Chiefdom, in the Kenema District, Eastern Province of Sierra Leone. These five local hand-dug wells were randomly selected based on the availability of water in them throughout the year. The physical characteristics examined are: pH, turbidity,...
Structural properties of high density polyethylene matrix composites reinforced with open air and furnace rice husks ash
December 2021
In this work, rice husks ash (RHA) was introduced to pure and recycled high density polyethylene (HDPE) matrix, at varying ration (0-50%) to formulate rice husks ash High density polyethylene (RHA-HDPE) composite. RHA was obtained by burning fresh rice husks either by open-air burning (oRHA) or furnace calcination at 700°C (fRHA). The composite samples were made by melt-mixing the HDPE in an oven at a...
Physicochemical characterization of Grewia species biopolymer, a potential coagulation-flocculation agent
July 2021
Powdered Grewia species barks was extracted in water and one part of the extract was precipitated with absolute ethanol. Both the crude water extract and the ethanol precipitate were freeze dried, pulverized into powder and subjected to physicochemical analyses. Amongst others, proximate composition, morphology and metal contents by Scanning Electron Microscopy with Energy Dispersive X-Ray (SEM-EDX), functional group by...
Analysis of the effect of feed composition and thermal conditions on distillation plant performance using a computer model
July 2021
This paper presents the effect of feed composition, xF, and feed thermal conditions on benzene-toluene distillation plant performance. An interactive computer model was developed to simulate the process using vapor-liquid equilibrium (VLE) data, mass and energy balances and McCabe-Thiele method. The feed thermal conditions studied were vaporized feed (VF), feed at its boiling point (FBP) and subcooled liquid (SCL) feed....
Extraction and characterization of chitin and chitosan from Callinectes amnicola and Penaeus notialis shell wastes
February 2021
In the current investigation, chitin and chitosan are extracted from Callinectes amnicola (crab) and Penaeus notialis (shrimp) shell wastes using predetermined optimization conditions. The shrimp shell produces higher chitin yield (26.08%), higher chitosan yield (16.93%) and higher degree of deacetylation (DDA) of 89.73% than the yields of chitin (19.36%), chitosan (13.29%) and the DDA from crab shell (84.20%). The...
Purification of cobalt solutions in several solvent extraction steps: Using MEXTRAL and D2EHPA as extractants
January 2021
A sulphate solution of cobalt (18.93 g/L Co2+) containing major impurities such as copper (1.35 g/L Cu2+), iron (0.28 g/L Fetot), zinc (0.70 g/L Zn2+) and manganese (4.83 g/L Mn2+) was purified through the solvent extraction method using two extractants; MEXTRAL and D2EHPA for the removal of copper and for the removal in two stages of a zinc-iron-manganese complex respectively....
Characterization of rice husk ash prepared by open air burning and furnace calcination
October 2020
Rice husk (RH) is an agricultural waste, and easily available in rice growing areas. The husk is mostly burnt as a way of getting rid of it. The ash obtained after burning or calcination may have economic application, mainly dependent on its properties. These properties in turn depend on the calcination method. However, for commercial viability, and for many applications, the calcination method should not only be as...
Synthesis and characterization of hemp and flax fiber reinforced geopolymer composites
July 2020
Reinforced Ordinary Portland Cement (OPC) has for a long time been a viable binder until the realization of its huge contribution to the excess carbon dioxide emitted in the atmosphere during its fabrication. The aim of this research work is to synthesize and characterize Collie fly ash based geopolymer composites reinforced with flax and hemp fibers. It was shown in this work that fiber reinforced geopolymer composites...
Akbari-Ganji’s method “AGM†to chemical reactor design for non-isothermal and non-adiabatic of mixed flow reactors
May 2020
In this paper, the chemical reactor with the energy changing (non-isotherm) and non-monotonic reactions in a mixed flow is investigated and also the sets of complex nonlinear differential equations obtained from the reaction behavior in these systems are solved by a new method. The set of differential equations are consisted of the mass equilibrium and energy (temperature) changing at concentration governing the...
Effect of plasma magnet power supplies operating temperatures on the thermal life of space-vehicles
May 2019
The galactic and solar radiation effect on astronauts in space during manned-space missions is one of the issues that scientists are dealing with to overcome this disaster. Furthermore, in space missions to Mars, Titan, and beyond, a powerful propulsion system is required. Recently, with the enhancement of technology in plasma generation, scientists tried to design and build a plasma radiation shield and plasma...
Finding the safest planet for carbon structures in terms of thermal life
April 2019
With achieving higher technologies, and as the population of our planet grows and sources of Earth consume every day, scientists are trying to find an alternative planet to build a second home for mankind. During the last decades, Mars seemed to be the first planet as a candidate for second home of human. Nevertheless, a few years ago a new planet has been discovered to be suitable for human life. Titan, Saturn’s...
Objects impact effect on thermal fatigue life of unidirectional T700 Carbon Fiber/Epoxy
February 2019
The main objective of this study is to investigate the effect of meteorites and debris impact on thermal fatigue life of unidirectional T700 carbon fiber/epoxy composite material. This composite material may be applied in space structures for space missions. These structures are exposed to thermal cycles as they go in and out of the planet’s shadow. If in this environmental condition, meteorites and debris impact...
Thermal life of space Elevators
December 2018
Since the introduction of space elevators by Tsiolkovsky in 1895, many researchers, engineers, and designers stepped forward to suggest theories for the construction of space elevators. Based on the investigations made by many authors for building space elevators, Earth-to-space, Lunar space, and Mars-to-space elevators can contribute for future space exploration and colonization. In the presented study, the aim is to...
Super reinforcement of MWCNT/Epoxy by considering thermal fatigue resistance management technology
November 2018
Strengthening fibers and layers in nanocomposites can make these materials suitable for many applications such as automobile, sport goods, aerospace, etc. Currently, scientists are still looking for materials with higher strength, but still lightweight because of consuming less fuel and energy in industries such as automobile and aerospace. In this research, by considering thermal fatigue resistance management...
Critical temperature estimation method for triple-walled carbon nanotubes (CNTs)/epoxy resin composite material
October 2018
The main objective of this research is to estimate the critical temperature for triple-walled carbon nanotubes (CNTs)/epoxy resin. Critical temperature in this study is the temperature that inter-laminar shear stress in interfaces of triple-walled CNTs and epoxy resin is the maximum value. At maximum inter-laminar shear stress, the stress concentration between triple-walled CNTs and epoxy resin is the maximum. This...
Effects of artificial aging heat treatment on mechanical properties and corrosion behaviour of AA6XXX aluminium alloys
September 2018
In this study, the effects of artificial aging heat treatment on mechanical properties and corrosion behaviour of AA6XXX alloy were investigated. The effects of artificial aging time on microstructure and mechanical properties of alloy were analysed and at the same time corrosion behaviour was determined by corrosion tests. For experimental investigations, the alloy samples prepared in appropriate sizes were heated to...
Production of bioethanol from stems of Sorghum saccharatum monitoring kinetic parameters of fermentation
September 2018
The objective of this study was to evaluate the performance of three stumps of Saccharomyces cerevisiae in the ethanol bioconversion of the diluted stems of sweet sorghum (Sorghum saccharatum L.) and to monitor the kinetic parameters of fermentation. Therefore, different initial concentrations of three stems from S. cerevisiae are used to ferment the juice. The juice obtained was formulated from one kilogram (1 kg) of...
Cycle numbers to failure for magnesium and its alloys in human body fluid
March 2018
The fundamental goal of this research is to provide a method to predict the fatigue life of Magnesium and its alloys in human body fluid environment. Estimation of fatigue life of Magnesium and its alloys in human body fluid environment can help doctors and patients to choose the best biomaterial for implantation surgery. This fact is true due to the reason that based on the fatigue life of these materials it can be...
Thermal fatigue life of carbon nanotube wire and unidirectional carbon fiber/epoxy composite (UCFEC) in earth orbit
November 2017
The most important target of this study is to develop a method to compare the materials’ degradation due to thermal fatigue and temperature variation between the carbon nanotube wire and unidirectional carbon fiber/epoxy composite (UCFEC). In the presented study, by using experimental results data, thermal fatigue life of carbon nanotube wire and unidirectional carbon fiber/epoxy was compared after being exposed...
Fatigue life prediction of unidirectional carbon fiber/epoxy composite on Mars
November 2017
In the presented study, by applying analytical methods and using experimental data, equations are achieved to predict the fatigue life of unidirectional carbon fiber/epoxy composite (UCFEC) that is applied in aerospace structures. The experimental data used to obtain these equations are achieved by low earth orbit (LEO) environment simulation experiment and other experiments. By employing convex curves analytical...
Failure of Nickel-based super alloy (ME3) in aerospace gas turbine engines
October 2017
The significant goal of this study is to develop a system to determine the margin of safety for ME3 super alloy in aerospace gas turbine engines. This margin of safety can be defined as critical temperature, force stress, exposure time, and cycles. In this research, by applying analytical solutions and using experimental data, equations are obtained to predict the life of a nickel-base super alloy in aerospace gas...
Mechanical properties of natural fiber reinforced polymer (NFRP) composites using anahaw (Saribus rotundifolius) fibers treated with sodium alginate
October 2017
Natural fiber reinforced polymer (NFRP) composites have been a focus of various research projects because of their advantages compared to traditional fiber reinforced plastics. In this study, Anahaw (Saribus rotundifolius) was used as fiber source because it is abundant in the Philippines. The fibers were treated by immersing in a sodium alginate solution and then in a calcium chloride solution. The treated fibers were...
Production of aluminium casting with open-cell aluminium foam core
August 2017
This research aims to investigate the influence of production conditions on the quality of aluminium casting with open-cell aluminium foam core. Open-cell aluminium foams were produced using vacuum pressure to aid molten metal to be fill into space of water-soluble space holders to obtain aluminum foams with specific pore sizes. The produced foams were then used as cores for castings. Optical microscope was employed...
Effect of nano-carbon percentage on properties of composite materials
July 2017
The presented study aims to investigate the role of nano-carbon percentage on material properties of different composites. Recently, nano-carbon composites are used in different industries like aerospace. Thus, it seems necessary to determine the best amount of nano-carbon in composite materials. The best percentage of nano-carbon can be defined as the amount that causes an increase in some of the useful...
Crack growth as a function of temperature variation in carbon fiber/epoxy
June 2017
The main objective of this paper is to develop a method to predict the crack length and crack growth rate in unidirectional carbon fiber/epoxy composite as a function of temperature variation. In order to measure the crack length and crack growth rate, a new analytical method by applying experimental procedure data is developed. By the novel analytical method, relations are achieved to predict the crack length and crack...
Photocatalytic oxidation of 17 α-Ethinylestradiol by UV-activated TiO2 in batch and continuous-flow reactor
May 2017
In this study, the photocatalytic oxidation by UV-activated TiO2 was investigated for the degradation of a 15 mgL-1 solution of 17 α-ethinylestradiol (EE2) in an ultra-pure water matrix. The TiO2 adsorption, solution pH and catalyst TiO2 concentration were evaluated. Operating as a batch reactor, the system showed a 90% removal, with a 40-min retention time, a pH value of 8 a TiO2 concentration of 0.1 gL-1, and a...
Addition of carbon tetrachloride as propulsion to the thermal cracking reactor based on the amount of coke formed in different coil outlet temperatures (COT)
January 2017
Nowadays, polyvinyl chloride (PVC) is the most usual plastic. Therefore, to make PVC, its monomer called vinyl chloride (VCM) must be produced first. It is a severely endothermic reaction that is done in an ethylene dichloride thermal cracking reactor within a temperature range of 680 to 758°K and pressure range of 2500000 Pascal. Thus, this cracking reaction changes into hydrochloric acid and VCM. In production...
A constitutive model on flow stress prediction from the contribution of twin and grain refinement, strain and strain rate during surface mechanical attrition treatment of metals
September 2016
A new constitutive equation is developed to model the flow stress on a metal surface undergone high speed impacts that result in strain hardening. The new equation is based on the Johnson-Cook model and has considered the effects of strain, strain rate, grain refinement, twin formation and twin spacing. Two mechanisms for the strain hardening are proposed: Grain refinement or twin formation, depending on the strain...
Preliminary research on strength of polymer modified concrete with copolymer natural rubber as concrete additives
August 2016
Polymer modified concrete is one of the alternative material of construction to obtain better performance in strength and durability of concrete. There are some types of PMC such as natural rubber, synthetic rubber, modified rubber and asphalt. In this work, copolymer of natural rubber styrene and copolymer of natural rubber methacrylate were used as PMC added to Portland cement concrete and Portland Pozzolan...
Development of leucite glass-ceramics for non-metallic dental product
August 2016
The objective of this study was to determine the potential of using Malaysian silica sand as the SiO2 raw material in producing leucite (SiO2-Al2O3-K2O) glass-ceramics. The crystallization, mechanical and biological properties of the glass-ceramic was studied. A starting glass composition in the system of leucite was melted in an electric furnace, quenched in deionized water and dry milled to obtain glass powder. The...
The effect of chitosan on physical and mechanical properties of paper
July 2016
Chitosan is a natural polymer gotten from shrimp and crab skeleton; chemical structure of chitosan is similar to cellulose where hydroxyl (OH) in glucose molecule in cellulose is replaced by amine (–NH2) in chitosan. From the chemical structure and its properties, chitosan can be used as a filler and adhesive to replace the traditional materials and it will improve several properties of papers such as to increase...
Effect of induced stress on the corrosion rate of medium carbon steel in saline environment
September 2015
This study investigated how 0.33% medium carbon steel is affected by induced stress in a saline environment. Three geometries namely U-bend, C-ring and I-shape samples were formed representing varying degrees of stress level induced on the samples. The test specimens were subjected to static loading in saline environment containing 15.0 wt.%, 10.0 wt.% and 3.5 wt.% of sodium chloride (NaCl) for a typical exposure time...
Chemical reactivity between CaCO3 and Ca(OH)2 in acid mine drainage (AMD) with mixing and shaking techniques during the destabilization-hydrolysis of the AMD
August 2015
The acid mine drainage (AMD) was poured into five 500 ml glass beakers. The samples were dosed with synthetic af-PFCl of Ca(OH)2 and af-PFCl of CaCO3 polymers respectively. The samples were treated in a jar test and a shaker at 250 rpm for 2 min, and thereafter were allowed to settle for an hour after which the pH, conductivity and turbidity (TSS) were measured. A similar second set of experiments was conducted by...
Comparison between mixing and shaking techniques during the destabilization-hydrolysis of the acid mine drainage (AMD) using Ca(OH)2 and Mg(OH)2
August 2015
Acid mine drainage (AMD) is detrimental to both humans and the ecosystem, and contains sulphuric acid and heavy metals, which have to be removed by dosing the coagulants. A 200 mL sample of AMD, emanating from a mining area in South Africa was poured into 500 mL glass beakers or Erlenmeyer flasks and were dosed with 0.043 M Ca(OH)2, 0.043 M Mg(OH)2 and synthetic 0.043 M CaMg.2(OH)2 and treated in a jar test or shaking...
Preparation of phosphoric acid activated carbons from Canarium Schweinfurthii Nutshell and its role in methylene blue adsorption
July 2015
Activated carbons were prepared by phosphoric acid activation of Canarium Schweinfurthii spent nutshell. The activation conditions for particles with average diameter of 2.36 mm, conducted in nitrogen chamber, were evaluated at 40 and 60% acid concentration, substrate/activating agent (impregnation) ratio of 1:1 to 1:4, activation time of 20 to 60 min and temperatures of 200 and 400°C. The results showed that...
Effects of mass transfer resistance and coking on yield during fluid catalytic cracking of heavy hydrocarbon fractions
April 2015
A transient model for an industrial fluid catalytic cracking (FCC) riser is here presented. The FCC riser models of previous researchers were mostly based on the assumption of negligible mass transfer resistance. This assumption reduced the accuracy of the models. In this work, the effects of mass transfer resistance and coking on the yield of FCC reactions were modeled and simulated. A five-lump reaction scheme was...
Effect of dioctyl phthalate (DOP) modified matrix on the thermal stability of glass fiber reinforced composite
October 2014
Unsaturated polyester was modified with dioctyl phthalate (DOP) and used as matrix in glass fiber reinforced composite. The effect on the thermal stability of the composite was studied in this work. The results of the modification showed that modified matrix had the best thermal stability at 5 wt% DOP with temperature of 373°C at 20% weight loss as compared with unmodified of temperature of 346°C at the same...
Steel making experience in the use of Nigerian Iron Ore at the Delta Steel Company, Nigeria
September 2014
The production of steel from the locally available Itakpe Iron Ore in Nigeria was achieved in the Delta Steel Direct Reduction-Electric Arc Furnace Plant. The ore was originally thought to be unsuitable for use in the direct reduction process due to its low total iron content, less than 64% and high gangue content which was in excess of 4% and above the maximum acceptable limit of 3.5%. Pilot and Plant tests were...
Antoine vapor pressure correlation: Generalization and prediction of coefficients of normal Alkanes
August 2014
This work presents two developments in Antoine vapor pressure correlation: (1) Generalization of the correlation using the principle of corresponding state; (2) Prediction of the Antoine coefficients form molecular weight. The coefficients of the generalized correlation are correlated to molecular weight (r2=0.99) for the group of normal alkanes (C1 to C20). The method is validated using experimental data obtained from...
Remediation of a simulated petroleum polluted water using pulverised used: Water sachet (Polyethylene)
July 2014
The potential of using used-water-sachets, a synthetic polymeric waste, which is not only readily available but indiscriminately littered around Nigerian urban and rural areas, as an adsorbent in removal of oil spilled on water was investigated. Used-water-sachets, a waste generated all over the country, has been converted into a low cost adsorbent. The sachets were collected, pretreated and pulverised to adsorb crude...
Utilization of Co-Zeolite imidazolate frameworks (Co-ZIF) as catalyst for organic transformations
June 2014
An excellent conversions of benzaldehyde was obtained under solvent and solvent free conditions by utilizing Co(im)20.5 DMA as catalyst for the synthesis of benzylidene malononitrile. The catalytic prospect of this crystalline porous framework was extended to oxidation reactions involving ethylene glycol (EG) and ethylbenzene (EB). Unexpectedly, EG was totally oxidized to oxalic acid; which demonstrates the catalyst...
Development and corrosion behaviour (Electrochemical Polarization Method) of aluminium alloy (LM-13) reinforced with Nano-ZrO2 chilled metal matrix composites (CNMMCs)
June 2014
This paper presents the results obtained and the discussion made from a series of corrosion experiments involving aluminum alloy (LM 13) reinforced with Nano-ZrO2, size of the particles dispersed varies from 100 to 200 nm and amount of addition varies from 3 to 15 wt.% in steps of 3 wt.%. The resulting CNMMCs are solidified under the influence of copper chill of 25 mm thickness to study the effect of corrosion behavior....
Characterization of palm kernel shell for materials reinforcement and water treatment
May 2014
As developing nations strive for economic sustainability, effort is geared towards exploiting biomass materials that could have alternative uses to their conventional low valued uses in order to achieve this goal. It is because of this that palm kernel shell, a byproduct of oil palm processing, is characterized for its application in construction and water treatment industries. The materials physical and chemical...
Inter-provincial cooperative control of air pollution in China
December 2013
Based on the status of the air pollution in China, three basic assumptions are proposed. The China’s inter-provincial cooperative control of air pollution (ICCAP) model is established by the combination of national optimization model and allocation model of cooperation benefit. A case study for the pollutant SO2 control in China shows that the proposed model is superior to the current command-order regulation. Our...
Extreme pressure property of Carbon Nano Tubes (CNT) based nanolubricant
December 2013
The paper predicts the exceptional extreme pressure properties of multi walled carbon nano tube as compared with traditional mineral oil which also contained some additives and graphite. The extreme pressure property was predicted by four ball tester. In the test the load bearing capacity of the newly developed nano oil was predicted to have a better value than the commercial available mineral oil. The weld load of the...
Time dependent mathematical model of air pollutants emitted from time-dependent elevated line source into a stable atmospheric boundary layer
December 2013
A time dependent atmospheric model is represented for chemically reactive primary pollutants emitted from an elevated line source into a stable atmospheric boundary layer, over rough surface terrains. The time dependent model was obtained through an analytical solution from a multiple Inverse Laplace transform of the atmospheric diffusion equation with the parabolic eddy-diffusion coefficient (exchange coefficient) and...
Characterization and optimization of poly (3-hexylthiophene-2, 5- diyl) (P3HT) and [6, 6] phenyl-C61-butyric acid methyl ester (PCBM) blends for optical absorption
November 2013
Thin films were developed, characterized, and optimized for optical absorbance from blends of organic polymer poly (3-hexylthiophene-2, 5- diyl) (P3HT) and the fullerene derivative [6, 6] phenyl-C61-butyric acid methyl ester (PCBM). The materials of both pristine and blends were analyzed using X-ray diffraction spectroscopy and high resolution transmission electron microscopy for structural properties, and fourier...
Solar photocatalytic degradation of phenol using nanosized ZnO and α-Fe2O3
November 2013
This work focuses on the solar photocatalytic degradation of phenol using nanosized ZnO and α-Fe2O3 synthesized via precipitation route. The synthesized ZnO and α-Fe2O3 were characterized using XRD, UV/Vis and surface area analysis. α-Fe2O3 was found to exhibit better solar photocatalytic activity than ZnO under identical experimental conditions due to the larger surface area and low band gap of...
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