Malaysian Journal of Microscopy

FACILE SYNTHESIS OF CNT COTTON/ZNO NANOCOMPOSITE USING WASTE COOKING OIL AS THE BIOTEMPLATE VIA HYDROTHERMAL/CALCINATION PROCESS

Wed, 20 Dec 2023 02:22:14 +0000

One of the common domestic wastes that are abundantly available is waste cooking oil (WCO) where improper disposal will create problems such as clogging the drain and/or related sewage system. Whether this carbon-rich waste can be up-converted for the formation of CNT and/or as a biotemplating agent for the formation of ZnO-CNT nanocomposite is the subject of interest of this research work. Therefore, the focal point of this work is to use this carbon-rich waste material, WCO as a biotemplate of ZnO growth onto the surface of carbon nanotube cotton (CNTC) for the formation of CNTC/ZnO nanocomposite. The results from the physicochemical analyses showed that WCO plays a dual role; as a carbon precursor for the formation of CNTC and as a templating agent to grow ZnO in the preparation of CNTC/ZnO nanocomposite. In the latter, the WCO was attached to the surface of CNTC and acted as the nucleation site for the ZnO growth which then formed the CNTC/ZnO nanocomposite, as indicated by the presence of the COO-Zn bond in their FTIR spectra. XRD studies showed the presence of the carbon, ZnO and iron oxide phases, confirming that the resulting nanocomposite is composed of CNTC and ZnO as the main components, while the presence of iron oxide is due to the catalysts that were used for the synthesis of the CNTC. The degradation of the sp2 graphitic phase was observed in the Raman spectra, indicating the defects of sp3 became prominent, due to the formation of the COO-Zn bond.

EFFECT OF GAMMA 60Co IRRADIATION ON MORPHOLOGY OF CARBON/SODIUM LAURYL SULPHATE (CARBON/SLS) USING A NOVEL SEM-EDS

Dhita Ariyanti, Deni Swantomo, Sidik Permana, Asril Pramutadi, Andi Mustari — Wed, 20 Dec 2023 00:00:00 +0000

Activated carbon is a material that has many benefits both in the health, energy such as storage materials and fuel cells, and industrial sector. Highly benefit of carbon material encourages researchers to activate it by various efficient methods. Activation carbon methods consist of two, by chemical and physical activation. Using chemical compounds, both acids, bases, and salts can increase carbon activity. Degradation of cellulose structure in natural materials by chemical compounds can increase its surface area. However, the presence of chemical compounds like acids and bases can pollute the environment. Another methods of activation carbon is electromagnetic waves used. In this research, electromagnetic wave irradiation will be carried out on carbon. The electromagnetic waves used gamma exposure from Cobalt-60 sources. Gamma electromagnetic exposure is clean energy without residual chemical compounds. This preliminary experiment aims to determine effect of 60Co gamma irradiation on the morphology of carbon materials at dose of 40 kGy using Scanning Electron-Energy Dispersion Spectroscopy Microscopy (SEM-EDS). The results showed that effect of irradiation exposure 60Co gamma on the morphology of Carbon/SLS was unsmooth particles formation, which indicates that Carbon/SLS can be used as adsorbent. Moreover, the presence of surfactant causes the carbon particles not to agglomerate or to be easily dispersed. 60Co gamma irradiation also causes carbon become rich in oxygen which comes from free radicals.

THREE-DIMENSIONAL YARN BALL-LIKE NICKEL COBALT OXIDE AS AN ELECTROCATALYST MATERIAL FOR FUEL CELL APPLICATION

Nor Fatina Raduwan, Norazuwana Shaari — Wed, 20 Dec 2023 00:00:00 +0000

The shape, size and specific surface area play a major contribution in determining the catalytic activity of an electrocatalyst. In order to control them, hydrothermal reaction time is one of important parameter tailoring the desired morphological and structures. Through this facile method, nickel cobalt oxide (NiCo2O4) has been successfully synthesized with various reaction time (6, 12, 18, 24h). The cubic spinel crystal of all the synthesized NiCo2O4 is obtained according to the standard pattern. The smallest crystallites size of 19.12 nm is obtained by powder synthesized for 18 hours based on the Scherrer formula calculation from X-ray diffraction (XRD) analysis. The field emission scanning electron microscopy (FESEM) micrograph demonstrates all the synthesized NiCo2O4 consists of three-dimensional (3D) nanoflakes that interconnected to each other and resemble a yarn ball with deteriorated structures when the reaction time is increasing. From Brunauer–Emmett–Teller (BET) analysis, the 3D yarn ball-like structures synthesized for 6 hours yield a very high specific surface area. The ultrathin nanoflakes provide a large surface area to accelerate the electrochemical reaction of the catalyst thus increase the performance of a fuel cell system. Hence, this 3D yarn ball-like NiCo2O4 synthesized by hydrothermal can be a promising electrocatalyst material for fuel cell application.

CHEMICAL AND MICROSCOPIC ANALYSIS OF WATER TREATMENT SLUDGE (WTS) FROM BUKIT SEBUKOR WATER TREATMENT PLANT

Tue, 19 Dec 2023 17:27:22 +0000

In the process of water treatment plant (WTP), a by-product known as water treatment sludge (WTS) are being accumulated in the landfills and thus will become a major concern in the near future. WTS has been examined to look into the potential reuse and rejuvenation. It is known that each WTP produces a different chemical composition which depends on the raw water intake and the treatment process. Thus, in this study, the chemical composition of the WTS will be assessed consistently for a period of 6 months. The samples were then examined using x-ray diffraction (XRD) and scanning electron microscopy with energy dispersive x-ray (SEM-EDX). Peaks observed in the XRD patterns of WTS were associated with the presence of zirconium, oxygen, aluminium, silicon, and sulphur. The results of SEM-EDX revealed that the WTS contained 29.94% to 47.65% of oxygen with aluminium in the range of 20.57% to 23.43%, silicon at 23.88% to 27.79%, and iron ranges from 4.48% up to 19.24%. The same elements were found in all WTS gathered during the six-month period. However, the results are slightly different from our preliminary data. Based on the results, it is concluded that the WTS is a clay with 70-90% purity. Further investigation is needed to find the sources iron and zirconium elements in the WTS.

FABRICATION OF WATER FILTER FROM RICE HUSK WASTE PRODUCT VIA COLD ISOSTATIC PRESSING (CIP) METHOD

Wed, 20 Dec 2023 00:00:00 +0000

Many researchers are interested in exploring the practical ways to expand the usage of RH waste. The objective of fabricating the silica water filter is to remove contaminants from the well water. The fabrication process involves burning Rice Husk (RH) waste at 550 °C, which produces black RH ash that contains a generous amount of amorphous silica. The silica water filter was fabricated with varying the compositions of silica rice husks which were 78 wt.%, 84 wt.%, and 88 wt.%. Porcelain and PVA has been added in the mixture and acting as a binder. The mixture of amorphous silica and binders have been used to fabricate the silica water filter by using Cold Isostatic Pressing (CIP) method. The CIP pressure used was 8 kPa and the mold used was rubber plastic. After compaction using the CIP method, the samples were sintered at a temperature of 1200 °C. The results obtained from the Scanning Electron Microscope (SEM) analysis provide visual insights into the pore structure of the sample under examination. Apparent porosity, and bulk density were recorded for each sample. The results obtained for the composition of 78 wt.%, 84 wt.% and 88 wt.% for the bulk density are 0.43861 g/cm3,0.3729 g/cm3 and 0.35143 g/cm3, respectively. The result for apparent porosity for every composition of 78 wt.%, 84 wt.% and 88 wt.% are 54%, 60% and 68%, respectively. The results indicate that the 78 wt.% silica composition produces the best silica water filter. Overall, our findings demonstrate a promising approach for repurposing RH waste and producing a sustainable water filtration solution.

PROPERTIES OF NATURAL HYDROXYAPATITE (HAp) EXTRACTED FROM BLACK TILAPIA FISH (BONE AND SCALE) USING CALCINATION APPROACH

Wed, 20 Dec 2023 00:00:00 +0000

Natural HAp was used from the bone and scales of Black Tilapia (Oreochromis Niloticus) fish, because it is less expensive than HAp made synthetically and safer than the mammalians bone. In this research, the calcination method at 1000 ºC was used to prepare and examine the characteristics of natural HAp from the black tilapia fish's bones and scales. Prior to heat treatment, grinding process was done in order to produce the natural HAp fine powder. The sample was characterized using Thermal Gravimetric Analysis (TGA) for thermal stability, Field Emission Scanning Electron Microscopy (FESEM) for morphological analysis, X- rays Diffraction (XRD) for phase identification, and Energy Dispersive X-rays spectroscopy (EDX) for chemical composition. From the result, TGA shows the extracted HAp had a relatively high thermal degradation temperature and the peaks of the HAp were visible on XRD. Additionally, the weight loss was tracked and used to validate that the sample’s organic components had been eliminated during the thermal calcination process. The morphological analysis from FESEM shows the particles have rod-like shape HAp crystals and EDX result showed a Ca/P molar ratio of both samples is close to stoichiometric HAp (1.67) which is 1.69 for fish bone and 1.73 for fish scale. Therefore, the calcination approach is an effective way to extract the natural HAp from fish waste.

COMPARATIVE ANALYSIS OF COATING METHODS ON MORPHOLOGICAL STRUCTURES AND BREATHABILITY OF TIO2 COATED FABRICS

Wed, 20 Dec 2023 00:00:00 +0000

TiO2 (titanium dioxide) has found diverse applications in textile products for self-cleaning and antimicrobial. To optimize the adherence of TiO2 on textiles, several coating methodologies have been implemented on cotton fabric surfaces. However, the effects of these coating techniques on the breathability characteristics of the fabric samples remain largely unexplored. To address this research gap, the present study elucidates the breathability attributes and morphology of TiO2 coated textiles. The polydimethylsiloxane (PDMS) was used as a binder to increase the adherence of TiO2 on cotton yarn. The study investigated three coating methods denoted as "after"(A), "before"(B), and "simultaneous"(S) methods, respectively. The analysis reveals that the (A) coating method exhibited strong TiO2 adherence to yarn surfaces, accompanied by minimal yarn weight loss (0.11%) compared to the (B) and (S) methods. The SEM micrographs showed that the PDMS was seen to coat over the TiO2 nanoparticles, making the particles trapped and bound to the cotton yarn surface. The presence of TiO2 and PDMS within the coated fabric was confirmed by EDX analysis. The study also found that TiO2 can enhance the breathability properties such as air permeability and water vapour permeability. The (A) method exhibited the highest air permeability with approximately (2577.3 mm/s + 3.3) compared to the (B) and (S) methods. Moreover, the A method and B methods demonstrated good water vapour permeability at about 503.5 g/m2/hr and 442.3 g/m2/hr, respectively. By undertaking this study, an enhanced property of cotton yarn was developed which is suitable for sportswear and casual wear.

GROWTH AND MORPHOLOGICAL FEATURES OF LOCALLY ISOLATED MICROALGAE CYCLOTELLA AND PAVLOVA

Siti Nor Ani Azaman, Fatimah M. Yusoff, Nur Maisarah Abd Rahim — Wed, 20 Dec 2023 00:00:00 +0000

Microalgae are a vast class of simple unicellular or multicellular autotrophic life forms with non-complex growth demands. Two factors that are important in preliminary assessments of microalgae are their growth profile and morphological characteristics. This study aimed to analyze the growth profile and the morphological characteristics of two local microalgae; Cyclotella meneghiniana and Pavlova noctivaga. Both microalgae were grown in Bold’s Basal Medium (BBM) with 10% inoculation and incubated at constant room temperature (25±1 °C) under the light (100 μmol photons m-1 s-1) in a 12h dark/12h light cycle for 21 days. Growth parameters such as specific growth rate and generation time were determined and their morphological feature was investigated using a light microscope and scanning electron microscope (SEM). From this study, C. meneghiniana showed 0.811 day-1 specific growth rate and 0.854 day-1 generation time, while P. noctivaga showed specific growth rate and generation time at 0.506 day-1 and 1.37 day-1, respectively. Preliminary morphological characterization using a scanning electron microscope for P. noctivaga showed a spherical shape with two unequal flagella. Meanwhile, C. meneghiniana showed a cylindrical shape under the light microscope. Besides, there are 12 radiating striae with indistinctive fultoportula in the center region, at both ends of the Cyclotella cell which was clearly seen under the scanning electron microscope. The information gained from the growth profiling study such as the growth rate, doubling time, specific growth rate and the morphology of the microalgae can be used and manipulated for future research.

EVALUATION OF TILAPIA FISH (OREOCHROMIS NILOTICUS) SKIN COLLAGEN HYDROGEL POTENTIAL AS BURN WOUND HEALING AGENT

Wed, 20 Dec 2023 00:00:00 +0000

Tilapia collagen consists of a complex structural protein that possesses biomaterial to accelerate wound healing activity. The aim of this study is to evaluate the potential effects of Oreochromis niloticus collagen hydrogel, as a burn wound healing agent. Collagen hydrogel of concentrations 0.05 mg/ml and 0.1 mg/ml were prepared via acid soluble collagen extraction and crosslinked with Carboxymethylcellulose. Sprague Dawley rats were used as test subjects and were grouped into negative control (with normal saline), positive control (using 1% silver sulfadiazine cream), two treatment groups (using 0.05 mg/ml and 0.1 mg/ml collagen hydrogel) and a normal group. A second degree burn wound was induced on the rats by using an electrical heater (at 100 °C), and collagen hydrogel of both concentrations were given daily for 14 days. The wound size, gross and histopathological changes were recorded. The burn wound treated with the collagen hydrogel of both concentrations had shown a decrease in size with an average diameter of 4 cm on day 0, and 2 cm at day 14, which was significant with p<0.05. The gross examination showed a decrease in diameter of the wound from day 0 to day 14. Histopathology result showed an increase of fibroblast presence, regeneration of hair follicles and sebaceous glands, decrease in inflammatory cells, increase in blood vessels, and restored epidermis layer on the 14th day of the treatment groups compared to the 14th day of the positive control. As a conclusion, the collagen hydrogel extracted from the skin of O. niloticus had displayed its potential as a burn healing agent, primarily by reducing inflammation and facilitating rapid proliferation of fibroblast.

MORPHOLOGY AND SIZE DISTRIBUTION OF PALM OLEIN CRYSTALS DURING FRACTIONAL CRYSTALLIZATION WITH BEHENIC ACID

Elina Hishamuddin, Mei Huey Saw — Wed, 20 Dec 2023 00:00:00 +0000

Fractional crystallization of palm olein is industrially practiced to produce superolein and soft palm mid fraction for food and non-food products. This process, however, is frequently complicated by prolonged nucleation induction times, sluggish crystal growth rates and inconsistent crystal sizes, often requiring seeding agents for process improvement. This study examined the morphology and size distribution of palm olein crystals during isothermal fractional crystallization at 15 °C with 0.25%, 0.5%, 0.75% and 1% behenic acid using optical microscopy and focused beam reflectance measurement (FBRM). Results showed that the addition of 1% behenic acid to palm olein significantly reduced the nucleation induction time to 30 min compared to 170 min in the control palm olein. Crystal size distribution analysis depicted that the highest crystal population was observed at 0.75% behenic acid concentration, with a mean crystal size of 31 µm. Above this concentration, the count rate decreased and crystal sizes exceeded 100 µm due to crystal growth and agglomeration. Furthermore, the addition of 1% behenic acid accelerated palm olein crystallization and increased the solid fat content of the crystallizing slurry to 22% from 15% in the control palm olein. Microscopic images revealed that behenic acid acted as heterogeneous nuclei, forming the cores of dense spherulites within the bulk oil. The findings from this study have demonstrated the potential role of behenic acid as a nucleation enhancer and crystallization rate promoter in facilitating palm olein fractional crystallization.

HISTOLOGICAL EVALUATION OF THE WOUND HEALING ACTIVITY OF ALLIUM AMPELOPRASUM METHANOL EXTRACT

Maryam Hameed Alwan, Ban A. Ghani — Wed, 20 Dec 2023 00:00:00 +0000

Allium ampeloprasum extract has the potential to facilitate wound healing due to its anti-inflammatory, antioxidant, and antibacterial properties. In this study, we aimed to investigate the potential wound-healing activity of the methanol extract derived from Allium ampeloprasum. Using 30 healthy male Wester rats; control group: 15 rats; normal saline applied locally instead of plant-extract. Experimental group: 15 rats received a daily local application of 200 mg/kg of the plant extract. Then, for each healing period of 0, 5, or 10 days, each group was divided into three-subgroups: A, B, and C, each with five rats. There was a significant difference in the percentage of wound contraction between the control and experimental groups (p 0.02). Moreover, at the 5 and 10 days healing periods, there was a significant difference in the inflammatory cell count, the experiment group showed a greater reduction in the inflammatory cells compared to the control group. Measuring the epithelial thickness revealed that the experiment group had considerably thicker epithelial layers (p 0.04). Allium ampeloprasum extracts have shown promising activity as wound-healing promoters. These extracts have many benefits in the management of acute wounds due to their capacity to increase wound contraction, minimise inflammatory cell infiltration, and boost epithelization.

ULTRASTRUCTURAL MORPHOLOGY STUDY AND OPTIMIZATION OF GROWTH CONDITIONS FOR LEPTOSPIRA INTERROGANS

Kok Xin Fang, Maizah Mohamed Yatim, Norefrina Shafinaz Md Nor — Wed, 20 Dec 2023 00:00:00 +0000

Leptospirosis is one of the often-neglected fatal zoonotic diseases endemic to most developing countries. The disease transmits mostly through contact of rodent urine contaminated with pathogenic Leptospira in the environment. The objectives of this study were to observe and understand the varied Leptospira interrogans ultrastructures, and to optimise the growth condition of the bacterium to better prepare for further evaluation and making of treatments against the bacterium. The ultrastructure of the bacterium was investigated using transmission electron microscopy. In this study, we have documented the varied terminal regions (hooked-end, entangled end, and horseshoe structure), Gram-negative-like cell wall, protoplasmic cylinder with or without flagella, detached flagella, cytoplasmic membrane, cytoplasmic formations extruding the cell wall, a variety of bud and outer membrane vesicle formations, and other peculiar features unique to Leptospira. These ultrastructures could be influencing the pathogenicity of a Leptospira strain but information on them is not well reported, hence the need for more morphological studies on this genus of bacteria. Furthermore, we investigated the growth of the bacterium by comparing the growth curves under different conditions. The necessity of serums and shaking incubation for faster growth and higher Leptospira yield were determined. It was observed that shaking incubation was essential for its optimum growth as the bacterium is aerobic. This study focuses on the many basics of Leptospira interrogans that were not much mentioned or discussed in other studies and would pave way for more detailed investigations of these characteristics and ultimately help in understanding possible approach for diagnostic and treatment in future.

ALUMINIDE COATING CHARACTERIZATION ON 304 SS USING SLURRY ALUMINIZING PROCESS

Wed, 20 Dec 2023 00:00:00 +0000

The application of aluminide coatings using the slurry aluminizing process has attracted significant attention in industry to enhance the corrosion resistance of structural materials exposed to severe environmental conditions. Nevertheless, several challenges have emerged, including the migration of aluminium from the coating into the substrate and mismatched in the coefficient of thermal expansion (CTE). To address these issues, 304 SS was chosen as the substrate due to its superior compatibility with the coating in terms of CTE. The objective of this project is to investigate the influence of various temperatures and durations on the formation of aluminide coatings containing alumina. The aluminide coating was created through a slurry aluminizing procedure, which involved mixing a slurry composed of 70% Al and 30% Al2O3 with polyvinyl alcohol (PVA). This coating was uniformly applied to the substrate. Subsequently, the coated samples underwent different heat treatment conditions, specifically at temperatures of 650 °C, 680 °C, and 700 °C, for durations ranging from 4 to 10 hrs. Detailed characterization of aluminide coating morphology, energy-dispersive X-ray (EDX), phases, porosity, and corrosion behaviour were evaluated using scanning electron microscope (SEM), X-ray diffraction (XRD), optical microscope (OM) and linear polarization (NOVA 1.7 software). Analysis using energy-dispersive X-ray (EDX) and X-ray diffraction (XRD) techniques revealed the presence of FeAl3 formation at the outermost layer and the development of the FeAl phase within the interdiffusion zone (IDZ). Remarkably, the samples that underwent heat treatment at 700 °C for 10 hours displayed significantly enhanced corrosion resistance. Consequently, the aluminide coating developed on 304 SS, characterized by the presence of the FeAl phase, demonstrates substantial potential for use as an effective protective coating.

FABRICATION AND CHARACTERIZATION OF FISH-DERIVED COLLAGEN SCAFFOLD LOADED WITH METRONIDAZOLE NANOPARTICLE FOR PERIODONTAL BONE REGENERATION

Wed, 20 Dec 2023 02:25:59 +0000

Periodontal disease poses a significant challenge to oral health, affecting the tissue and bone supporting the teeth. Tissue engineering emerges as a promising approach for restoring periodontal tissue and preventing bone loss using scaffolds. However, concern arises when using collagen sourced from mammals like porcine and bovine in scaffolds regarding halal status and disease transmission. Additionally, conventional treatment involves systemic antibiotics to control infection, leading to adverse side effects. This study aims to develop a scaffold using fish-derived collagen incorporated with metronidazole nanoparticles (MNP) and analyze scaffold properties while indirectly addressing safety and halal concerns. The scaffold was fabricated by physically cross-linking collagen derived from the tilapia fish (Tilapia mossambica) and chitosan, with metronidazole nanoparticles (MNP) incorporated into the blend. The scaffold underwent analysis of its physical characteristics, morphology, and pore size using a scanning electron microscope (SEM), swelling, and biodegradability in phosphate buffer solutions (pH 7.4, 37 °C). The fish-derived collagen-chitosan exhibited a consistent three-dimensional (3D) physical structure and optimal pore sizes (>100 µm). Scaffolds with MNP concentrations ranging from 0 to 40 w/t% displayed excellent swelling ability and biodegradability, exceeding 80%. As the concentration of MNP increased, the scaffold’s biodegradation rate slowed, suggesting potential as a controlled drug release vehicle aligned with the rates of new bone formation in vivo. In conclusion, the 3D porous scaffold with metronidazole nanoparticles met important criteria for physical structure, pore size, swelling ability, and biodegradability. These halal-compliant scaffolds hold promising potential for applications in tissue engineering and drug delivery and are subject to further in vivo and in vitro studies.

HYDROPHOBIC SURFACE OF Zn-Al-WO3 HOT DIPPED GALVANISED COATING MODIFIED WITH DIFFERENT MOLARITY OF STEARIC ACID

Wed, 20 Dec 2023 02:28:36 +0000

Hot dip galvanizing is the oldest and most cost-effective corrosion resistance method for steel, acting as both a physical barrier and a sacrificial effect. Galvanised steel, on the other hand, corrodes when exposed to harsh environments over time. Thus, increasing the hydrophobicity of galvanised steel can reduce corrosion rates and increase service life. The purpose of this study is to investigate the effect of stearic acid on the formation of a hydrophobic structure of Zn-Al-WO3 on mild steel. Hot dip galvanizing was used to coat the Zn-Al-WO3 on mild steel. The coated sample was surface treated with stearic acid in varied molarities ranging from 0.002 to 0.05 M. The surface treated coating was analyzed using scanning electron microscopy (SEM), field emission scanning electron microscopy (FESEM) equipped with energy dispersive X-ray (EDX), water contact angle (WCA), and atomic force microscopy (AFM). The corrosion resistance after surface treatment was assessed using the potentiodynamic polarization method in a 3.5% NaCl solution. The results demonstrate that the 0.008 M stearic acid had a greater WCA at 122.29o with a surface energy of 10.42 mJ.m-2. This 0.008 M stearic acid also provided the best surface roughness and corrosion rate, with minimum values of 21.30 nm and 0.707 mmyr-1, respectively. This study found that 0.008 M is the ideal concentration of stearic acid for modifying the hydrophobic surface and can be employed for Zn-Al-WO3 galvanised coating.

MICROSTRUCTURE EXAMINATION AND TENSILE PROPERTIES OF Al-20%Mg2Si-XZRO2 HYBRID COMPOSITES

Hamidreza Ghandvar, Tuty Asma Abu Bakar, Mostafa Abbas Jabbar — Wed, 20 Dec 2023 02:32:08 +0000

Due to the unique properties of aluminium hybrid metal matrix composites (Al hybrid MMC) such as physical, mechanical, and tribological properties, these materials recently achieved considerable attention particularly in automotive and aerospace applications. These unique properties are the result of the presence of two or more reinforcement particles in the composite matrix. In the present study, various concentrations of Zirconium oxide (ZrO2) particles were introduced to the Al-Mg2Si composite via stir casting technique. The influence of various concentrations of ZrO2 on the structural and tensile properties of the Al-Mg2Si composite was examined using Scanning Electron Microscope (SEM) and tensile tests, respectively. The findings showed that the introduction of ZrO2 to Al-Mg2Si decreased the average mean size of primary Mg2Si particulates. Adding ZrO2 particles up to 10 wt.% had a decent distribution in the Al-Mg2Si matrix; however, increasing the ZrO2 content to 15 % led to agglomeration of ZrO2 particles. Furthermore, tensile results demonstrated that Al-Mg2Si composite with 10% ZrO2 addition demonstrated the highest Ultimate Tensile Strength, UTS (75.35 MPa) and elongation, El % (0.69 %) compared to other fabricated composites. Hybrid composite fracture surface with 10% ZrO2 revealed a more ductile fracture mode compared to other fabricated composites. This study can be beneficial to tailor new composites with refine structure and high mechanical properties.

PETROGEOCHEMISTRY OF RARE EARTH ELEMENTS (REE) FROM HULU LANGAT AND BALING, MAIN RANGE GRANITE PROVINCE, MALAYSIA

Wed, 20 Dec 2023 02:33:47 +0000

The research focused on the petrogeochemistry of potential weathered granitoids containing rare earth elements (REEs) in Peninsular Malaysia's Main Range Granite, specifically in the Hulu Langat and Baling region. Through mineralogical and geochemical analyses using methods like petrographic examination, XRF, XRD, and ICP-MS. Both regions are in the Western Belt Main Range S-type granitoids, Peninsular Malaysia. However, the mineralogy and geochemistry characteristics of the rock will be different. Thin sections were done to study the rock petrology which indicates, samples are granite rocks. There are minerals like quartz, biotite, and mica in rock samples, indicating limited weathering. There were six samples from Hulu Langat which is 1A, 2A, 2B, 2C, 3B and 4A while seven samples from Baling which is 1A, 2A, 3A, 4B, 6C, 8E and 9E. Selected samples from Baling were carried out several analyses. XRD analyses from Hulu Langat shown that presents of clay minerals like kaolinite, nacrite, quartz, microcline, muscovite while Baling samples shown that present of kaolinite which was formed from the weathering process. XRF analysis shown that both samples consist of major oxide compounds such as Al2O3 and SiO2 in the high concentration. ICP-MS results indicates that the TREE concentration of 8.583 ppm in sample 1A from Hulu Langat while 6.863 ppm in sample 1A from Baling. The lowest concentration 0.227 ppm in sample 3B.

OBSERVATION OF THE SILK-GLAND SYSTEM IN ARGIOPE MODESTA: A POTENTIAL SOURCE FOR BIOMATERIAL SCAFFOLD

Wed, 20 Dec 2023 02:35:12 +0000

Spider silk, which contains spidroin, is a biomaterial widely used in regenerative medicine. Argiope modesta, an orb-web spider found in Indonesia, produces silk via its glands. However, the structure of the gland has not yet been explored. The purpose of this study was to examine the silk gland system, including the morphology of the spider fiber of Argiope modesta. The ultrastructure of the silk gland system surface was observed using scanning electron microscopy. The histological structure of the seven glands in the spider was observed using hematoxylin-eosin staining. Scanning electron microscopy revealed the structure and morphology of the spider fiber, spinneret, and spinning tubes. The diameter of the spider fibers was 850 µm. The minor ampullate, major ampullate, aggregate, flagelliform, tubuliform, pyriform, and aciniform spinning tubes were observed on the anterior, median, and posterior spinnerets of Argiope modesta via scanning electron micrographs. Histological analysis revealed the structure of the spider silk glands. The aggregate, flagelliform, aciniform, and tubuliform glands were clearly visible. This study revealed that the silk-gland system of Argiope modesta, which is responsible for producing spider silk, has distinct properties. Further studies are needed to analyze the chemical components of spider silk produced in different glands of Argiope modesta.

CHARACTERIZATION OF POLYMETALLIC-GOLD DEPOSIT OF EASTERN MANSON’S LODE, ULU SOKOR, KELANTAN

Wed, 20 Dec 2023 02:36:26 +0000

Polymetallic gold in Manson’s Lode pit and Ulu Sokor Gold Mine in Kelantan are hosts to significant gold (Au) and base metal deposits. The deposit is hosted in Permo-Triassic meta-sedimentary and subordinate volcaniclastic rocks. Field observation and geochemistry sampling of ore zones have been carried out in Manson’s Lode Eastern pit to determine the type of sulphide minerals and ore composition in the ore body. The Eastern Pit is the hard rock extension below the main ore body, and this condition provides good samples for geochemistry sampling. Selected samples were collected and prepared for lab analysis using Scanning Electron Microscope (SEM) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to confirm field observations of ore mineral composition. The polymetallic ores were subdivided into three main zones of mineral association. The upper zone is sheared carbonaceous host rock with pyrite-galena veins localized along the shear zone. The middle zone is rich with sphalerite-galena-pyrite within quartz carbonate veins and hosted within meta-siltstone. The lowest zone is dominated by pyrite with localised sphalerite. ICP-MS analyses of six ore samples indicate the average content of elements is 103,333 ppm iron (Fe), 4,031.7 ppm lead (Pb), 5,000.0 ppm zinc (Zn), 1,937.3 copper (Cu), and 0.6 ppm gold (Au), which represent the sulphide minerals pyrite, galena, sphalerite, chalcopyrite, and gold, respectively. However, Cu and gold are erratic across the ore zone and much higher grade in the upper zone. The gangue minerals include quartz and carbonates consisting of calcite, siderite, and dolomite. The Pearson correlation coefficient matrix shows the relationship between the elements in this deposit. The correlation determined for 20 elements shows that Au is well correlated with Cu, Bi, Sb, Sn, Te, Co, and Ni.

POLYANILINE/GRAPHENE NANOPLATELETS-SILVER (PANI/GNPs-Ag) NANOCOMPOSITES TREATED VIA NON-COVALENT SURFACE FUNCTIONALIZATION METHOD

Wed, 20 Dec 2023 02:38:23 +0000

PANI/GNPs is one of the most promising conductive polymer nanocomposite materials due to its unique properties, easy synthesis, and low cost. The main aim of this study was to prepare and characterize the morphological and non-covalent functionalization of GNPs nanofiller for improving the matrix-filler interaction between the PANI matrix and GNPs nanofiller. PANI/GNP nanocomposites were prepared via oxidation polymerization of aniline with various GNP nanofiller loadings at 0.25 wt.% into 1.00 wt.% of non-covalently treated GNPs. Subsequently, the PANI/GNPs nanocomposite with excellent conductor of electricity has been selected for producing PANI/GNPs-Ag hybrid-filled nanocomposites with variable Ag nanofiller loadings. The resulting PANI nanocomposite filled with 1.00 wt.% weight percent Ag nanofiller and non-covalently treated GNPs has been characterized by SEM, TEM, and FTIR analysis. SEM micrographs show that GNPs nanofillers show good interaction and dispersion within the PANI matrix. Transmission electron microscopy (TEM) demonstrated the non-covalent surface treatment influencing polymer chains in suspensions and preventing the re-agglomeration of GNPs. FTIR peaks confirmed the formation of the C-N stretching band of aromatic amine, the C-C stretching vibration in the quinoid and benzenoid rings and the C-C stretching vibration of the pyrene ring and carboxylic acid. Overall, it has been proven that the combination of conductive polymer and metal-GNP hybrid composite could change the functional group and physical characteristics of PANI-based nanocomposites.

INFLUENCE OF CuO, Ag AND Zn ADDITIVE MATERIALS ON THE PROPERTIES OF BARIUM STRONTIUM COBALT FERRITE CATHODE FOR SOLID OXIDE FUEL CELL APPLICATION: A SHORT REVIEW

Wed, 20 Dec 2023 02:40:14 +0000

Alternative energy sources are necessary to meet the world’s energy needs. One of the most capable technologies for energy conversion in the future is solid oxide fuel cells (SOFCs). The development of SOFCs has attracted great attention worldwide, particularly for intermediate low-temperature applications. The commercialisation of SOFCs can be accomplished after satisfying a few system requirements and discovering suitable material candidates. Hence, this review was constructed to study the current approach of material development for intermediate-temperature SOFCs and the influence of additive materials on the properties of barium strontium cobalt ferrite (BSCF)-based cathodes. This article discussed three types of additive materials, i.e. copper oxide (CuO), silver (Ag) and zinc (Zn), focusing on their chemical, physical, thermal and electrochemical characteristics. The additive material was substituted in the B-site of the BSCF cathode to improve cell performance. In addition, the additive materials have remarkably improved the cathode performance and chemical stability. The addition of CuO was intended to increase chemical bonding and enhance the cathode’s electrochemical reaction activity. On the one hand, the addition of Ag offers improved oxygen surface adsorption and dissociation of molecular oxygen into atomic oxygen. On the other hand, the addition of Zn can provide excellent thermal stability and good oxidation resistance and enhance the electrocatalytic activity of the oxygen reduction process. Therefore, this review focuses on identifying the influence and suitable additive material for BSCF perovskites regarding their chemical and physical properties for outstanding SOFC performance.

FABRICATION AND CHARACTERIZATION OF RICE HUSK SILICA WATER FILTER: A SHORT REVIEW

Putri Syalabiah Abdul Rahim, Hamimah Abdul Rahman, Sufizar Ahmad — Wed, 20 Dec 2023 00:00:00 +0000

Due to the high demand for water filtration technology in developing countries, various materials have been used for water filter fabrication. However, silica derived from rice husk was believed to be a low-cost agro waste due to the abundant production of the waste material has several benefits needed by industries due to its chemical and physical properties. Researchers were interested in using rice husk-derived materials for water purification in variety forms such as biochar, activated carbon, silica, and hydrogels. In order to fabricate effectively filter water, it is important to consider its morphology, structure, chemical composition, and surface area, which draws scientists to develop new technologies. Therefore, this review is carried out to see how things are currently done to the excellent technique for ceramic filter made up husk-based silica and their characteristics. In this article, two types of manufacturing processes, namely dry pressing and slip casting, and their morphology, porosity and density, and phase analysis were studied. The analysis showed that the sintering temperature and the composition of the raw material significantly improve the morphology and porosity of a silica water filter. However, the technology of silica water filters still needs to be improved and modified so that it can be used to treat various environmental pollutants.

PROPERTIES OF SAMARIUM STRONTIUM COBALT OXIDE BASED COMPOSITE CATHODE WITH DIFFERENT ELECTROLYTES FOR INTERMEDIATE TEMPERATURE SOLID OXIDE FUEL CELL: A SHORT REVIEW

Wed, 20 Dec 2023 00:00:00 +0000

Solid oxide fuel cell (SOFC) is a promising technology for energy conversion efficiency. Electrochemical processes convert the chemical energy of a variety of substances into direct current power. Typically, these reactions occur at temperatures between 400 and 1000 °C. In recent years, a substantial quantity of research has been conducted on intermediate temperature SOFCs (IT-SOFCs), with a particular emphasis on the cathodes. However, the effect of electrolyte on composite cathodes has not been studied as thoroughly. Current SOFC research focuses on enhancing cell performance by decreasing operating temperature. It is crucial in this context to analyze the efficacy of various electrolytes. Gadolinium-doped ceria (GDC) and samarium-doped zirconia (SDC) are two such electrolytes that can be coupled with samarium strontium cobalt oxide (SSC) cathodes. In SSC-based cathodes, the electrolyte material strengthens the triple phase boundary, thereby enhancing cell performance. Chemically compatible with altered ceria electrolyte materials, SSC is appropriate for SOFCs operating at intermediate temperatures. Specifically, SSC nanofiber-GDC electrolyte composite cathodes exhibit superior thermal stability. In addition, their cathode polarization resistance at 650 °C is only 0.024 cm2. This review indicates that perovskite SSC is a formidable candidate for use in IT-SOFCs. To optimize cell efficacy, however, additional research is required. This research should center on the chemical, physical, and electrochemical compatibility of cathode materials. In conclusion, the future of SOFCs depends on the optimization of these factors, and the potential of SSC-based cathodes in this sector is an exciting prospect.