Hybrid solar still with addition of charcoal and oil palm fiber ash for seawater desalination

Solar still is an evaporator where solar energy is used to produce fresh water from saline or brackish water but suffer low thermal efficiency and low yield. Therefore, a solar still with biomass application as alternative solar thermal energy storage is attractive to explore because it is a simple technique for desalination, cheap, low energy consumption and environmentally friendly. The objective of this research is to study the effect of solar still cover inclination angle, water depth and biomass (charcoal and oil palm fiber ash (OPFA)) application in solar still for seawater desalination. The solar still was designed and fabricated. The biomass, charcoal and OPFA, was used as thermal storage. The effect of depth of seawater (1cm to 4 cm,) the cover inclination angle (10 to 40) and biomass to seawater mass ratio (1:50, 1:100 and 1:500) were investigated. The experiment was carried out under sunny daylight for seven hours from 10.00 a.m. to 5.00 p.m. The water quality of spend seawater and evaporated water was analyzed by determining the pH, conductivity, total dissolve solid (TDS), Chemical Oxygen Demand (COD) and turbidity. The fresh and spent biomass were characterized by using Brunauer Emmet Teller (BET), X-Ray Detector (XRD) and Scanning Electromagnetic Microscope (SEM). The OPFA has high carbon and metal oxides content including SiO2, K2O, CaO and other traceable oxides. Meanwhile, the charcoal has high content of carbon and large pore sizes. The surface of charcoal and OPFA was stable after testified in the seawater. Without biomass application, it is found that 30º cover inclination angle contributed to the highest yield of evaporated water production (6.68 wt%). The depth of seawater at 1cm has the highest temperature (51 °C) and yielded 6.14 wt% of evaporated water. The present of charcoal and OPFA in solar still significantly enhanced the performance of solar still. It is found that highest yield of evaporated water was achieved when the biomass to seawater mass ratio was at 1:100. Addition of charcoal produces more fresh water than OPFA. A 17% of evaporated water yield and seawater temperature of 60 °C were achieved when charcoal was used in hybrid solar still. Meanwhile, 11.6 wt % of evaporated water yield and 53 °C of seawater temperature was achieved when OPFA was used. A 60 % and 58.5% reduction of COD was also obtained when charcoal and OPFA was used respectively. The pH, conductivity, COD and turbidity of the evaporated water that produced from solar still complied with drinking water quality standard. In conclusion, charcoal and OPFA application are able to increase the water temperature, produce more evaporated water and reduce the impurities in polluted water

Skull stripping of MRI brain images using mathematical morphology

Skull stripping is a major phase in MRI brain imaging applications and it refers to the removal of its non-cerebral tissues. The main problem in skull-stripping is the segmentation of the non-cerebral and the intracranial tissues due to their homogeneity intensities. As morphology requires prior binarization of the image, this paper proposed mathematical morphology segmentation using double and Otsu’s thresholding. The purpose is to identify robust threshold values to remove the non-cerebral tissue from MRI brain images. Ninety collected samples of T1-weighted, T2-weighted and FLAIR MRI brain images are used in the experiments. The results showed promising use of double threholding as a robust threshold value in handling intensity inhomogeneities compared to Otsu’s thresholding

Effect of Calcination Temperature on Performance of Photocatalytic Reactor System for Seawater Pretreatment

Conservative desalination technology including distillation requires high energy and cost to operate. Hence, pretreatment process can be done prior to desalination to overcome energy demand and cost reduction. Objective of this research is to study the effect of calcination temperature of hybrid catalyst in photocatalytic reactor system in the seawater desalination, i.e. salt removal in the seawater. The catalyst was synthesized via wet impregnation method with 1:1 weight ratio of TiO2 and activated oil palm fiber ash (Ti:Ash). The catalyst was calcined at different temperature, i.e. 500 oC and 800 oC. The study was carried out in a one liter Borosilicate photoreactor equipped with mercury light of 365 nanometers for two hours with 400 rpm mixing and catalyst to seawater sample weight ratio of 1:400. The Chemical Oxygen Demand (COD), pH, dissolved oxygen (DO), turbidity and conductivity of the seawater were analyzed prior and after the testing. The fresh and spent catalysts were characterized via X-Ray Diffractogram (XRD and Nitrogen physisorption analysis. The calcination temperature significantly influenced the adsorption behaviour and photocatalytic activity. However, Ti:Ash which calcined at 800 oC has less photocatalytic activity. It might be because the surface of fiber ash was sintered after calcined at high temperature. The Ti:Ash catalyst that calcined at 500 oC was found to be the most effective catalyst in the desalination of seawater by reducing the salt concentration of more than 9 % compared to Ti:Ash calcined at 800 oC. It can be concluded that catalyst calcination at 500 °C has better character, performance and economically feasible catalyst for seawater desalination.

Deep Learning on Wound Segmentation and Classification: A Short Review and Evaluation of Methods Used

The abundance of research on wound segmentation suggests that it is significant in order to provide a good analysis and assistance in the medical field. Although there is some relative dearth of wound segmentation on other approaches, this review finds that deep learning is central to the objective of image segmentation. Here, the review informs on the methods that are credible towards wound segmentation, training, classification, validation of datasets, data collection, and evaluation of segmented images. While the literature establishes a clear connection between the segmentation algorithms of the object, therefore this study seeks to find the segmentation algorithm directly applicable to wound assessment

Oil palm fiber ash characterization and application in solar evaporator for seawater desalination

Solar evaporator is a non-conventional technology, cheapest, cleanest process and simplest technique for seawater desalination. However, low thermal efficiency is the main problem in solar evaporation process. The objective of this paper is to study the effect of oil palm fiber ash application in seawater evaporation of seawater to produce clean water. The spent and fresh oil palm fiber ash were characterized by using Nitrogen Adsorption (BET), X Ray Detector (XRD) and Scanning Electromagnetic Microscope (SEM). The investigation was conducted in a 0.4m x 0.45m x 0.15m basin type solar evaporator. The oil palm ash to seawater mass ratio was varied from 1:50 to 1:500. The investigation was carried out for eight hours in sunny daylight. The water qualities including pH, conductivity, total dissolve solid (TDS), chemical oxygen demand (COD) and turbidity of the seawater and the evaporated water were determined. It was found that the addition of oil palm fiber ash in the seawater increased the seawater temperature to 57 °C when the oil palm ash to seawater mass ratio of 1:100 was used. The maximum temperature was achieved at 1:00 pm. About 12 % of evaporated was produced at the same condition. Interestingly, the COD value of seawater reduced drastically when oil palm fiber ash was used. The pH of the seawater increased slightly after the investigation might be due to the mineral content of oil palm fiber ash content which rich in CaO. It can be concluded that the application of oil palm fiber ash improve the performance of the solar evaporator and increase the production of evaporated water

A study of nanoparticles as a drug carrier on the wall of Stenosed Arteries

The influences of nanoparticles as drug carriers on the walls of stenosed arteries are presented. In this study, three nanoparticles namely Fe3O4 , TiO2 and Cu were used. It is observed that the addition of Fe3O4 nanoparticles tends to reduce the resistance impedance of blood temperature in bell shaped stenosed arteries. The blood temperature increases slightly in the streamwise direction before the throat region. Thereafter, the blood temperature increases at a higher rate and reaches its maximum value at the stenosis throat. It is found that the temperature distribution is heavily dependent on parameters such as periodic body acceleration and Prandtl number

Statistical Texture Mean-Windowing Feature of Snake Identification

Snake identification has been explored in various domains such as the image processing domain. In Malaysia, many of the snake species are non-venomous but still dangerous to the human. Conventionally, snake identification is evaluated by collecting the information from the patient. However, it is very hard and difficult to recognize the venomous and non-venomous snake types. Also, doctors need to inject the anti-venom into the patient which produced the side effect. Therefore, this paper classified the venomous snake of Naja Kaouthia and other venomous snake species. All the image datasets have been captured at Malacca Butterfly & Reptile Sanctuary, Melaka. The statistical vectors are extracted by using the normalized mean-moving windows. The taxonomical statistical texture vectors of snake region features are classified using Tree, K-Nearest Neighbor, Support Vector Machine, and Naïve Bayes classifiers. Results showed that most of the classifiers produced an accuracy rate of 100%

Mesoporous Ce-doped Ti:Ash Photocatalyst Investigation in Visible Light Photocatalytic Water Pretreatment Process

The treatment of organic pollutants in water including semiconductor photocatalysis is a promising approach to disinfect water. The objective of this study is to investigate the effect of Ce loaded on mesoporous Ti:Ash catalyst for water pretreatment process. The mesoporous Ti:Ash catalyst that doped with Ce was synthesized through wet impregnation method with 5%, 10%, and 15% weight percentage of Ce doped on 40:60 Ti:Ash. The photocatalytic properties were characterized through X-ray powder diffraction, scanning electron microscopy with energy-dispersive X-ray spectroscopy, N2 adsorption-desorption studies and diffuse reflectance UV–vis absorption spectroscopy. It is found that the Ti:Ash nanocomposites doped with Ce shifted the light absorption band-edge position to the visible region. Moreover, the Ce doped Ti:Ash has large surface area and pore diameter. The Ce doping could significantly improve the absorption edge of visible light and adjust the cut-off absorption wavelength from 404 nm to 451, 477 and 496 nm for 5%, 10% and 15% Ce-doped mesoporous Ti:Ash catalysts, respectively. As the Ce doping ratio increased, the band gaps decreased from 3.06 eV to 2.53 eV. The most contaminant reduction up to 45% was achieved when Ti:Ash:Ce 40:55:5 was used. Higher Ce loading on the photocatalyst may reduce the photocatalyst performance because supernumerary metal loading on TiO2 can block TiO2 defect sites which are necessary for the adsorption and photoactivation. The OPFA also acts as an adsorbent for some pollutants besides, reducing the water salinity. It can be deduced that the hybrid TiO2 photocatalyst that synthesized with OPFA and doped with Ce has huge potential to treat seawater prior to commercial seawater desalination process. Copyright © 2020 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Controlling the blood flow in the stenosed porous artery with magnetic field

The unsteady blood flow in the stenosed porous artery subjected to a magnetic field was studied analytically. Oscillating pressure gradient and periodic body acceleration were imposed on the flow field. The effects of the magnetic field and the permeability of the stenosed artery on the blood velocity were studied. The results showed that the magnetic field affected the flow field significantly which can be beneficial for some practical problems

Pulsatile blood flow through a constricted porous artery

In this paper a speculative study of an incompressible Newtonian blood flow through a constricted porous channel and pulsatile nature is inspected. Porosity parameter λ is incorporated in the momentum equation. Governing nonlinear differential equations are numerically evaluated by employing the perturbation method technique for a very small perturbation parameter ε 1 such that ε ≠ 0 and with conformable boundary conditions. Numerical results of the flow velocity profile and volumetric flow rate have been derived numerically and detailed graphical analysis for different physical parameters porosity, Reynolds number and stenosis has been presented. It is found that arterial blood velocity is dependent upon all of these factors and that the relationship of fluid velocity and flow is more complex and nonlinear than heretofore generally believe. Furthermore the flow velocity enhanced with Reynolds number, porosity parameter and at maximum position of the stenosis/constriction