Search

Utilizing silicon dioxide (SiO2) & aluminum oxide (Al2O3) as dielectric materials, the capacitance voltage properties of circular MEMS actuators will be modeled and assessed. With twenty people split evenly between the two groups, we are using a pretest power of 80% and an error rate of 0.05. Both dielectric materials had their capacitance voltages (CV) tested at both the pull-in & post-pull-in voltages, and the results are shown. The Al2O3 based MEMS actuator provides mean capacitance at below pull in state is found to be 6.81 x 10−11 F and capacitance at post pull in state is found to be 1.50 x 10−10 F, while the SiO2 based MEMS actuator provides mean capacitance at below pull in state is found to be 2.17 x 10−11 F and capacitance at post pull in state is found to be 4.39 x 10−11 F. The results show significance of 0.0001 (p < 0.05). The capacitance of Al2O3 dielectric material-based MEMS actuators is significantly higher than SiO2. [ABSTRACT FROM AUTHOR]

Utilizing silicon dioxide (SiO2) & aluminum oxide (Al2O3) as dielectric materials, the capacitance voltage properties of circular MEMS actuators will be modeled and assessed. With twenty people split evenly between the two groups, we are using a pretest power of 80% and an error rate of 0.05. Both dielectric materials had their capacitance voltages (CV) tested at both the pull-in & post-pull-in voltages, and the results are shown. The Al2O3 based MEMS actuator provides mean capacitance at below pull in state is found to be 6.81 x 10−11 F and capacitance at post pull in state is found to be 1.50 x 10−10 F, while the SiO2 based MEMS actuator provides mean capacitance at below pull in state is found to be 2.17 x 10−11 F and capacitance at post pull in state is found to be 4.39 x 10−11 F. The results show significance of 0.0001 (p < 0.05). The capacitance of Al2O3 dielectric material-based MEMS actuators is significantly higher than SiO2. [ABSTRACT FROM AUTHOR]

This project aims to find the compressive strength of the recycled AA5051 alloy with and without reinforcing novel SiO2 using the stir casting method. Materials and Methods: The reinforcing particles used were novel silicon dioxide with a particle size of less than 50 nm, and the matrix materials used were recycled AA5051 alloys. To achieve consistent reinforcement distribution in matrix materials, it was casted using a stir cast method at a melting temperature of 720°C and a stirring speed of 500 rpm. Two types of samples were prepared using recycled AA5051 alloy (Control Group 1), Silicon dioxide reinforced AA5051 alloy nanocomposite (Experiment Group). Each group had a sample size of 20, with a pre-test power of 80%, a beta of 0.05 %, and a CL of 95%. The compressive strength of the novel silicon dioxide reinforced recycled AA5051 alloy was analyzed and compared with the control group material by using SPSS-V26 software. It was noted and observed that the significance of synthesized nanocomposites p=0.000 (2-tailed) was attained, which is lower than (p<0.05). This indicates that there is a statistical significance obtained between the control and experimental groups. Within the limitations of present study, it was found that there was an upgrade in the compressive strength of novel silicon dioxide reinforced recycled AA5051 alloy composites improved by 69.9% within the study's limitations. [ABSTRACT FROM AUTHOR]

Due to high demand of energy at present time oil and gas companies start looking to produce from the unconventional reservoirs but due to environmental challenges it is not possible to produce by using the current drilling fluids that where nanomaterial comes in to play due to their unique size which made it possible to come up the harsh environmental challenges such us high temperature and pressure. This study aims to find the effects of silicon dioxide on the properties of water-based drilling fluid. First base mud was created keeping the solvents in mind to make sure that there is no effect of dispersion and silicon completely dissolved in the base mud and reach homogeneity. The results show that there is 18.6% reduction was seen in plastic viscosity, 31% increase yield strength, 25% increase in gel strength, 18.6% reduction in fluid loss and 19.04% reduction in mud cake thickness. [ABSTRACT FROM AUTHOR]

This research work aims to improve the V-I characteristics of a CNTFET (Carbon Nanotube Field Effect Transistor) having Al2O3 (Aluminium oxide) and compare SiO2 (Silicon dioxide) as oxide material by varying the Source/Drain (S/D) length by using nanohub. Al2O3 and SiO2 were chosen as two groups, consisting of 26 samples each. The sample size was calculated with the G power of 80 % and alpha value is 0.05. These V - I characteristics were simulated by varying the Source / Drain of the CNTFET materials using the CNTFET lab tool in NANOHUB. The materials Al2O3 and SiO2 as oxide material have the maximum drain current for 2.5 nm S/D length as 8.862 x 10−7A and 9.332 x 10−7A respectively. The Independent T test was done which reveals that the Al2O3 was found to be statistically significant as 0.000 (p < 0.05). This analysis found that Al2O3 based Novel CNTFET has significantly better voltage current characteristics compared with SiO2 based CNTFET. [ABSTRACT FROM AUTHOR]

Replacement of the contents of concrete mixture with different types of solid waste is considered to be a good solution for sludge disposal. Replacement cement with pulverized brick wastes is a sustainable eco-friendly solution, which has a pozzolanic specification on the concrete mixture. In this study two types of brick powders were used as a partial replacement for cement; Pulverized clay brick waste (PCBW) and pulverized burnt clay brick waste (PBCBW). Brick was ground to produce (PCBW) and burnt to 700°C to produce (PBCBW) with different particle shapes and agglomeration and study its effect on the concrete mixture. The percentage of replacement was 10% for both PCBW and PBCBW, according to many researches this percentage is considered to be the ideal value for the replacement. Then samples are molded in 150 mm cubic, cured for 7 days, and others for 28 days, these periods are expected to be enough to give an indication of the suitability of the brick wastes replacement. Chemical composition, SEM, and EDX were analyzed, furthermore, compressive strength results showed that replacement with PBCBW at 28 days of curing was greater than PCBW, and the higher Ca/Si ratio gives PBCBW more cementitious properties. Furthermore, PBCBW contains a higher ratio of less reactive crystalline silica (SiO2) than highly reactive amorphous silica, which increased the compressive strength of PBCBW at 28 days. [ABSTRACT FROM AUTHOR]

Using sodium borate and silica from oil palm leaves (Elaeis guineensis) (OPL), a low-cost, environmentally friendly alternative method was developed for the synthesis of sodium borosilicate. Calcination at 900 °C was used to afford the product, which was then identified using X-ray difactometry (XRD). The analysis results revealed a broad band at 2θ= 27° and 2θ= 47°, indicating that the prepared glass samples were amorphous. Even though the FTIR analysis did not clearly show the vibration type of Si-O-Si and B-O, it is thought by XRD analysis that sodium borosilicate can be made by mixing sodium borate with silica. [ABSTRACT FROM AUTHOR]

Using the in situ polymerization method, an alternative method was developed for the synthesis of green polyaniline-silica (PANi-SiO2) composites from aniline monomer and bio-silica filler derived from oil palm leaves (Elaeisguineensis) (OPL). The synthesized substances were then characterized with X-ray Diffraction (XRD) and Fourier Transform Infrared (FTIR) and compared to pure PANi. The presence of peaks in the X-ray diffractogram of pure PANi confirmed that the polyaniline formed was amorphous. The PANi-SiO2 composite X-ray diffractogram displayed a new signal, indicating the presence of amorphous silica. In addition, the FTIR spectrum changes also support the presence of the silica compound in the composite. According to the findings of this study, SiO2 was identified in the PANi-SiO2 composite. [ABSTRACT FROM AUTHOR]

Amorphous silica (SiO2) made from natural sand has been synthesized through the precipitation method. The natural sand used comes from the coast of Bangka Belitung and the Lumajang river. The process parameters in this amorphous silica study were variations in NaOH concentrations of 6M, 7M and 8M. Characterization of the formation of amorphous silica includes XRD and XRF tests. Preliminary analysis using XRD shows that both types of sand are in the quartz phase. After extraction using NaOH and 2M HCl there was a change in the distribution angle of the two types of samples. The results of characterization and XRD analysis showed that the silica formed was in an amorphous phase. The highest purity of silica was produced at a concentration of 8M NaOH with an average percentage of 96.7% for Bangka Belitung beach sand and 96.2% for Lumajang river sand. [ABSTRACT FROM AUTHOR]

This study made observations on mineralogy, petrological, and petrographic textures related to diagenesis and traces of methane presence in cuttings samples in sedimentary rock in well XS-01, Makassar Strait, Indonesia. The research methods carried out included a description of the cuttings sample, XRD, and petrography aimed at obtaining information on mineralogy, petrology, and diagenesis aspects of rocks, as well as documenting petrographic texture of the presence of methane in samples that prove the presence of methane in the recent past. The results showed that the identified mineralogy are calcite, quartz, amorphous silica, kaolinite, and montmorillonite. The rock types include claystone, siltstone, wackestone, packstone, and crystalline limestone. There are three (3) petrographic textures related to diagenesis: fracturing, calcite cementation, and silicification. Cement is drusy calcite and amorphous silica, representing the diagenesis stage of mesogenesis. The micrite petrographic texture shows as clotted peloidal micrite in wackestone, which was interpreted as a product of microbial activity during carbonate mineral precipitation stimulated by the Anaerobic Oxidation of Methane (AOM) process. This texture indicates the remnant of methane that characterizes the biogenic gas from the chimney gas zone. The gas chimney is common geological structures within the subsurface realm, which is recorded on the seismic sections.very easy to see or easily distinguished from other geologic features on the seismic section. However, the characterization of mineralogy, petrology, and petrographic textures is still rarely found in the literature due to limited accessibility to the interior of gas chimneystill quite rare. In this study, observations were made on mineralogy, petrological, and petrographic textures related to diagenesis and traces of methane gas presence in cuttings samples in sedimentary rock in well XS-01, Makassar Strait, Indonesia. The research methods carried out included a description of the cuttings sample, XRD test, and thin-section petrography aimed at obtaining information on mineralogy, petrology, and diagenesis aspects of rocks, as well as document-ing petrographic textures of traces of the presence of methane gas in samples that prove the presence of methane gas in the recent past. The results showed that the identified mineralogy are calcite, quartz, amorphous silica, kaolinite, and montmorillonite. The rock types include claystone, siltstone, wackestone, packstone, and crystalline limestone. There are three (3) petrographic textures related to diagenesis, namely fracturing, calcite cementation, and silicification. Cements are, with the types of cement including drusy calcite and amorphous silica which represent the diagenesis stage of mesogenesis. The micrite petrographic texture shows as clotted peloidal micrite in wackestone which were interpreted as a product of microbial activity during carbonate mineral precipitation stimulated by the Anaerobic Oxidation of Methane process. This texture is an indicator of remnant of methane that characterizes the biogenic gas from the chimney gas zone. [ABSTRACT FROM AUTHOR]

The main aim of this research work is to simulate, analyze the drain current characterizes for GFET (Graphene Field Effect Transistor) device. To improve the drain current by varying the top gate oxide device in the Sio2 (silicon dioxide) and Hfo2 (Hafnium oxide) device. There are two groups (Sio2 and Hfo2) consider for this work with a simple size of 20 each is calculated using a pretest power of 80% with an error rate of 0.05. The GFET (Graphene Field Effect Transistor) using Hfo2 (Mean 2.1440) has a better drain current compared with Sio2 (Mean 0.4884) with its statistical significance value of 0.014 (p<0.05). This paper revealed that using Hfo2 to have better performance then that of Sio2. [ABSTRACT FROM AUTHOR]

The purpose of this study is to improve the drain current of a metal-oxide-semiconductor field-effect transistor (MOSFET) by using nanotechnology to reduce the oxide thickness from bulk to nanoscale and comparing it with conventional MOSFETs. Conventional and novel nanoscale MOSFETs were selected as a group of 24 samples each. Silicon oxide (SiO2) and hafnium dioxide (HfO2) are the oxide materials of choice for both conventional and nanoscale MOSFETs. The 24 samples were calculated with a pretest power of 80% and an alpha of 0.05. The maximum drain current for the silicon dioxide layer for conventional and nanoscale MOSFETs is 4.16 mA (100 nm thickness) and 8.34 mA (10 nm thickness). For hafnium dioxide as the oxide layer, the maximum currents of conventional MOSFET and nanoscale MOSFET are 36.41mA (100nm thickness) and 72.85mA (10nm thickness), respectively. Analysis independent samples t-test, significance reached 0.000 (p<0.05). The drain current of the new nanoscale MOSFET (average drain current - 40.67 mA) is significantly better than conventional MOSFETs (average drain current - 19.94 mA) with various gate oxide materials and thicknesses. [ABSTRACT FROM AUTHOR]

Silica extracted from clay of Kendari Bay has been studied. The clay was first rinsed with deionized water and dry under daily sunlight. The dried clay was then crushed and sieved of 60 meshes. Silica was obtained by leaching method using hydrochloric acid (HCl) with concentration varied from 4M to 10M with increment of 2M. During leaching process, the mixture was left for stirring at 100°C for 5 h, rinsed until neutral pH and filtered. The samples were characterized using X-ray Fluorescence (XRF) to know chemical composition of clay, X-ray Diffraction (XRD) for structural properties and Fourier Transform Infra-Red (FTIR) for functional groups. The results showed that the optimal condition for silica extraction is 6 M of 64.588%. XRD result revealed that the Bragg peak with high intensity situated at 2 = 26,6° is identified as SiO2 with Miller index of 101 of quartz type. FTIR result shown that the peak situated on 1.050 cm−1 was identified as Si-O-Si functional groups. The, we concluded that the clay of Kendari Bay was became the source of silica. [ABSTRACT FROM AUTHOR]

In modern days, electrical and electronic systems use capacitors in various ways. It's very rare for an electrical product not to contain a capacitor. Metal oxide semiconductor (MOS) capacitors are a good energy source in modern times due to their special properties. A metal oxide semiconductor (MOS) capacitor consists of a substrate, Indium-Tin Oxide (ITO), and the conducting side of this Indium-Tin Oxide (ITO) is coated with an efficient metal oxide (like Silicon dioxide (SiO2), Zinc oxide (ZnO)). Zinc oxide is among the most viable metal oxide semiconductors because of its large band gap. In this report we mainly focus on the structural, vibrational, and morphological study of Zinc oxide (ZnO). To synthesize and characterize the zinc oxide nanostructure, we utilize the most feasible method possible, which is the sol-gel method. The research mainly centers on the comparison study between the Nano and microparticles of Zinc oxide (ZnO) and metal oxide semiconductor (MOS) capacitor applications of both. [ABSTRACT FROM AUTHOR]

The current research work aims to improve the quality of silica rock from Grade C (SiO2=98.75%) to Grade A (SiO2=99.8%) to fulfil the requirements for high specification products. The raw silica rock was characterized with 98.75% SiO2, 0.410% Fe2O3, 0.1750% Al2O3, and 0.067% TiO2. The Fe2O3 content has been successfully reduced to less than 0.008% and 0.002% for Class B and Class A product applications, complying with the requirement of MS701:2017. To enhance the recovery of silica, the removal of impurities from the silica rock was investigated. The leached specimens were characterized by wet method, inductively coupled plasma atomic emission spectroscopy (ICP-AES), and scanning electron microscopy (SEM). Among the different extractants used, sulphuric acid (H2SO4) demonstrated the highest recovery of SiO2 at 99.85% with significant reduction of undesirable impurities present in the silica rock e.g., Al, Cr, Ti, and Fe. In comparison, oxalic acid (C2H2O4) and citric acid (C6H8O7) as organic extractants yielded relatively lower silica recovery, where 99.53% purity silica was achieved using citric acid at 0.25M concentration, constant leaching temperature of 60 °C of 150 rpm., and constant speed of agitation of 150 rpm. [ABSTRACT FROM AUTHOR]

Silica in amorphous form is a promising material for many applications such as fillers, sensors, catalytic materials, and biomedical fields. This research aim is to fabricate amorphous silica from silicone oil using a gradually roasting process. The roasting process is carried out in stages starting from the breakdown of the silicone oil as precursor material at a temperature of 300°C followed by the second stage of the roasting process at a temperature of 700°C. The characterization of amorphous silica obtained from silicone oil was carried out using the X-ray diffraction technique (XRD) to determine the structure of the composition of the compound, electron microscopy-energy dispersive X-ray (SEM-EDX) to determine the morphology of the resulting product, and X-ray fluorescence (XRF) analysis to determine the level of product composition and level of purity. The results of the XRD characterization showed that the amorphous silica was formed. The results of the characterization with SEM have a soft white spherical morphology. The results of EDX silica content resulting from this roasting process showed silica oxide with Si and O elements with no other impurities. The results of the XRF analysis showed that the SiO2 content was above 97.15%. [ABSTRACT FROM AUTHOR]

Ferronickel slag is a by-product of ferronickel processing. The amount of ferronickel slag is comparatively large to ferronickel products with a ratio of 6:1. The content in ferronickel slag that can still be utilized is silica (Si) and magnesium (Mg), its two largest main compositions. With a very high content of up to 50%, Si can be extracted as silica precipitates. Silica precipitates is widely used for various industrial applications such as paints, bitumen, ceramics, glass, absorbents, fillers, and others. The manufacturing process of silica precipitate from ferronickel slag used in this research consists of several stages. The initial stage is the drying of ferronickel slag in an oven at a temperature of 110°C for 8 hours. The next step is to mix the ferronickel slag with sodium carbonate in a ratio of 1:1 (wt.%/wt.%) using a mixer for 1 hour. The roasting process is carried out at a temperature of 900°C in a muffle furnace for 2 hours. The roasting results are then dissolved in water with room temperature variations up to 100°C, a leaching time of 1 to 4 hours, solids: water weight ratio of 1:5, and stirring speed of 500 RPM. The last step is to precipitate silica by titration the sodium silicate solution using hydrochloric acid, filtering the silica precipitate formed, and finally drying the silica precipitate in an oven at a temperature of 110°C for 8 hours. The results of XRD analysis show an amorphous silica reference graph which is an indication of the silica precipitates formation. This is also supported by the results of SEM-EDS mapping which shows the distribution of silica element along with oxygen which is very dominant in a large area. Moreover, the XRF results on silica precipitates also showed that the SiO2 content analyzed is of 96.071%. [ABSTRACT FROM AUTHOR]

Heavy metals can cause long-term environmental hazards due to its feature of toxicity, bioaccumulation, and non-degradable. Heavy metals can be obtained from volcanic dust and human activities such as domestic waste and industrial waste. One of the widespread heavy metals such as lead (Pb) can be detrimental to human health. The removal of Pb in the environment has been carried out through several methods. One of the most efficient methods denotes by using adsorption. Commonly, adsorbents are used to remove Pb including activated carbon, zeolite, and silica. As one of the adsorbent materials, silica is widely used in purification and separation due to its adsorption properties, high surface area, and porosity. Rice husk has the potential to be used as a source of raw material for making silica. Silica from rice husk can be collected using the sol-gel method as a simple way. This review recommends the modification process through the addition of diphenylcarbazide immobilization onto the silica. This modification may increase the adsorption capacity of silica towards Pb. This review finding indicates that modified silica with diphenylcarbazide immobilization could potentially be applied as an adsorbent to remove Pb, implicating a potentially novel application in the treatment of environmental pollution. [ABSTRACT FROM AUTHOR]

Precious metals, such as gold, silver, platinum, palladium, and rhodium, play a significant role in our modern life. Due to the dwindling of natural resources, secondary resources, such as waste, hold significant importance as an alternative resource for these precious metals. Over the years, silica nanoparticle has taken great interest due to their unique properties, high thermal stability, high surface area, and homogenous pore size distribution. Recent studies showed that silica is mainly used in drug delivery, absorbent, hydrogen storage, and chromatography support. Functionalized silica nanosphere was used in the adsorption of Au(III) from an aqueous solution. The adsorbent was characterized by using SEM, XRD, and FTIR. Various parameters were carefully studied, such as pH, kinetic, and isothermal. The functionalization process did not significantly alter the physicochemical characteristic of the silica nanosphere. The results showed that functionalized silica nanosphere exhibit a fast reaction kinetics for the adsorption of Au(III). According to the results, Au(III) was chemically adsorbed onto the adsorbent, and the reaction followed a pseudo-second-order kinetic model. The equilibrium data fitted well with the Langmuir isotherm model with a maximum adsorption capacity of 103 mg g−1. This study highlighted a simple process of functionalizing silica-based adsorbent that could allow the adsorption of precious metals onto the adsorbent. The adsorbent performed excellently in recovering precious metals, providing insight into a sustainable way to acquire precious metals. [ABSTRACT FROM AUTHOR]

Silicon carbide whiskers and fiber-like structures are of keen interest because of their useful mechanical properties at high temperatures, as well as their reinforcing ability in metal and ceramic matrix composites. An interestingly unique approach has been taken in the current work to grow whiskers of silicon carbide-based composite through simultaneous utilization of solution combustion synthesis (SCS) and high-speed temperature scanner (HSTS). In particular, a homogeneous mixture of silicon oxide, carbon and alumina was firstly produced by combustion synthesis of alumina impregnated solution of silicon dioxide gel and alanine in the presence of ammonium nitrate as an auxiliary oxidant. By the next step, the pellet obtained from the SCS product was heated up to 1600oC by HSTS setup leading to the formation of silicon carbide whiskers in the alumina matrix. [ABSTRACT FROM AUTHOR]

We expect to help one more noteworthy type of gentle weight sizeable squares by utilizing minerals which achieves monstrous development in strength. The first explanation for this is to decrease the use of every now and again same substance which significantly increases the force. Basically, new minerals rely on the supply of fabric shut by means of put and particularly behavior of samples. These boundless sorts of mineral samples by means of and through accessibility, these may be replaced as substitute bonding substances, for instance, flutter garbage, flowstones, silicon dioxide exhaust for example earth impact radiator gossan, yet fabric conduct not the slightest bit been richly researched, to analyze the enormous appropriate proportion gentle proportionate substances sizeable squares is what it act & recommend for the power property moreover business endeavor practicality watching out. To focus on their amicability limits of texture when used with aluminum dioxide in the gentle weight standard size squares. [ABSTRACT FROM AUTHOR]

Carbon fibers are one of the most explored fibers which are widely used for various advanced applications in aerospace, nuclear, missile technologies etc. The aim of this work was to deposit amorphous silica on the carbon fiber (Cf) tow using Radio Frequency plasma enhanced chemical vapor deposition method (PECVD) based on bipolar pulse power. The silica (SiO2) was deposited at room temperature using precursor, tetraethyl orthosilicate (TEOS) under the influence of Argon plasma. A 13.56 MHz radio frequency was used to generate the plasma and the plasma power was 250W. The deposited coating on fiber was characterized by using XRD, SEM and EDS for structural identification, morphological studies and elemental composition respectively. The coated Cf was further subjected to thermal oxidation for knowing the thermal resistance of the coated Cf against the oxidation at temperatures from 400-600 °C which could enable its efficient use in advanced composites. [ABSTRACT FROM AUTHOR]

Many researchers are presently investigating the hybridization of aluminium chips due to commercial value, improved properties, and potential applications in aircraft, vehicles, and marine vessel production technologies, as well as to obtain more benefits, such as improved performance, cheaper prices, and less environmental impact. This research examines the effect of alumina (Al2O3) and rice husk silica (RHA) as reinforcement on the recycled aluminium alloy (AA7075) chip using the cold compaction process, in which the sample is compressed in a die using a hydraulic press. The aluminium AA7075 chip was reinforced with i.e., 0.5 wt.%, 3.0 wt.%, 5.5 wt.%, 8.0 wt.% and 10.5 wt.% at 63 µm size of RHA, and alumina powder at the sizes of 1.0 µm, 5.0 µm and 35.0 µm. The microstructure images show the random arrangement and various sizes of Al alloy chips in these matrix composite. The density for the sample 0.5RHA/Al2O3 reinforced AA7075 with a particle size of 35.0 µm of Al2O3 has the highest density at 2.5654 g cm−3, while the sample 3.0 RHA/Al2O3 reinforced AA7075 with a particle size of 1.0 µm of Al2O3 has the lowest of density at 2.3522 g cm−3. The porosity and water absorption were inversely proportional to the density. The porosity and water absorption increased until 3.0 wt.% of RHA and decreased to 10.5 wt.% of RHA. The increment of reinforcement composition causes an increase in the porosity due to clustering and pore nucleation between the matrix and reinforcement. However, the water absorption level corresponds with the presence of porosity inside the specimen. Based on investigation, the combination of agro waste and synthetic reinforcement can improve the properties of AMC. [ABSTRACT FROM AUTHOR]

Additional of metal oxide such as copper oxide, lithium oxide and iron oxide into ceria-based electrolyte had been commercialized to improve the performance of the ceria based material in microstructure modification. In this study, the effect of samarium doped ceria with the addition of rice husk ash silica on its characterization is described. Samarium doped ceria (SDC) with addition of 1.0 wt.% of rice husk ash silica (RHASiO2) was prepared by ball milling method. The SDC-RHASiO2 composite pellets were produced by uniaxial press and were sintered at 700°C. Material characterizations of SDC-RHASiO2 sample were identifying by X-ray diffraction (XRD) for crystalline structures, porosity test and scanning electron microscope (SEM) for surface morphology and microstructures. Based on XRD result obtained, it has been found that the result for SDC-RHASiO2 powder only showed the face-centered cubic lattice structure of (Sm.20Ce.80O1.90) without additional impurity phases. SEM micrographs indicated that the porosity percentage decreases when the RHASiO2 was added into SDC. This mixed material is believed could improve the structure as well as the performance of undoped SDC. [ABSTRACT FROM AUTHOR]

A nanoparticle is a branch of nanotechnology that deals with nano-scale materials with very small particle sizes ranging from 1 to 100 nm. Metal oxide nanoparticles are more promising than the many other nanoparticles available because they have unique physical, chemical, and biological properties. Zinc oxide is one of the abundantly produced metal oxides after silicon dioxide and titanium dioxide. However, these methods of production are typically costly, labour-intensive, and can harm the environment and living organisms. Therefore, green synthesis (biosynthesis) is a good alternative where plants are used to assist nanoparticles synthesis which has eco-friendly benefits compared to chemical and physical methods. This biosynthesis method uses simple procedures, easily accessible raw materials, and a conducive environment for the synthesis process, where the precursors are safe and reduce the possibilities of harmful by-products being produced. Therefore, this review paper is focused on summaries of the biosynthesis of Zinc oxide nanoparticles from leaf extract such as Mangifera Indica (Mango), Ixora Cocconea (Jungle Geranium), Corymbia Citridora (Lemon-scented Gum) as a new development of green technology beneficial to the environment and to the plant itself. It also describes the progress made in the understanding of the mechanism routes reported in this review. [ABSTRACT FROM AUTHOR]

Rice husk is known as one of the popular silica resources. Through the optimum burning condition, such as the combination of appropriate burning temperature and duration of this agricultural waste, rice husk ash (RHA) that contains a high percentage of amorphous silica could be obtained. Therefore, this paper aims to highlight the effect of burning temperature and duration on the content of silica and the colour of the RHA produced, as well as to characterize the properties of white powder obtained from the acid-leached and thermal-treated RHA. The cleaned rice husk was subjected to different burning temperatures in the range of 700°C to 1000°C and different burning duration in the range of 1 hour to 4 hours. These RHA had been characterized through XRF, and the colour of RHA at each parameter had been observed. This study discovered that the optimum burning condition was at 800°C for 4 hours which yielded the whitest powder that contained up to 87.16% of silica. Meanwhile, the powder obtained was characterized by XRD, XRF, FTIR and SEM. High-purity silica powder was obtained by combining acid leaching and thermal treatment of RHA while maintaining its amorphous structure throughout the process. Silica with these properties has high potential and was more in demand in application due to its high reactivity during a reaction. [ABSTRACT FROM AUTHOR]

Additional of metal oxide such as copper oxide, lithium oxide and iron oxide into ceria-based electrolyte had been commercialized to improve the performance of the ceria based material in microstructure modification. In this study, the effect of samarium doped ceria with the addition of rice husk ash silica on its characterization is described. Samarium doped ceria (SDC) with addition of 1.0 wt.% of rice husk ash silica (RHASiO2) was prepared by ball milling method. The SDC-RHASiO2 composite pellets were produced by uniaxial press and were sintered at 700°C. Material characterizations of SDC-RHASiO2 sample were identifying by X-ray diffraction (XRD) for crystalline structures, porosity test and scanning electron microscope (SEM) for surface morphology and microstructures. Based on XRD result obtained, it has been found that the result for SDC-RHASiO2 powder only showed the face-centered cubic lattice structure of (Sm.20Ce.80O1.90) without additional impurity phases. SEM micrographs indicated that the porosity percentage decreases when the RHASiO2 was added into SDC. This mixed material is believed could improve the structure as well as the performance of undoped SDC. [ABSTRACT FROM AUTHOR]

High electronic energy loss of swift heavy ions (SHIs) generates thermal spikes due to their passage through a material. The spatial and temporal evolution of the thermal spike within a metal nanoparticle (NP) embedded in dielectric surroundings can be evaluated using the three-dimensional thermal spike model (3DTSM). In this work, we have utilized this model to investigate the effect of 100 MeV Au ion on a 5 nm Au NP surrounded by silica matrix at two different ambient temperatures of 77 K and 300 K. The temperature evolution of electronic and lattice subsystems is reported. Our result shows that the radius of the ion track in silica is 7.3 nm and 7.8 nm for ambient temperatures of 77 K and 300 K respectively. The ion track form due to melting and subsequent re-solidification of the molten zone in a modified state. The lattice temperature of the Au NP increases by indirect heating as bulk Au is insensitive to thermal spike. The temperature of Au-silica interface increases initially and rapidly moves towards the center due to the high thermal conductivity of Au. The effect of ambient temperature on the evolution of thermal spike is found to be insignificant. Our simulation indicates the temperature of the NP surpasses the melting and vaporization temperature of gold which supports the mechanism proposed to describe experimental findings. [ABSTRACT FROM AUTHOR]

In the research,a study was done the structural and optical properties of pure and doped SiO2 films with Cr, which were manufactured by Sol-Gel technology and deposited by dipping in order to study the characteristics of pure and doped silicon dioxide. The resulting products characterized by X-ray diffraction (XRD), atomic force microscopy (AFM), and UV-visible absorption were studied. Where the X-ray diffraction examination of the pure and doped SiO2 thin film showed a spectrum in the form of a broad band with an equivalent Bragg angle of 2θ = 22.6°, which indicates that the obtained material is amorphous silica. Surface morphology was measured by atomic force microscopy. The surface roughness decreases with the increase of the doping percentage with a minimum value (7%) and through UV-Vis examination, We note that the energy gap has decreased from (5.65-2.51 eV) due to the increase in the percentage of chromium doping for good absorption in the visible and ultraviolet regions. We also note that by increasing the percentage of doping, the minimum energy gap is at a concentration of 3%. [ABSTRACT FROM AUTHOR]

In this study, preparation of two categories of aluminum composite materials by stir casting process one of them is SiO2 particles as a reinforcement embedded in (Al-1%Cu) matrix with added weight percent (2, 4, 6, 8 and 10), while the other is SiO2 particles coated electroless and electroplating with copper embedded in Al-Alloy. The reinforcement weight percent are (2, 4, 6, 8, and 10) after the casting, cut the samples into the suitable dimension according to each test. Mechanical tests such as hardness, compression, XRD, and SEM observation have been conducted. From these results, it is easy to show that the hardness and compressive strength improved by increasing the silicon oxide percentage in the aluminum base. [ABSTRACT FROM AUTHOR]

Recent advancements in hybrid AMC have led to utilizing agro waste derivatives as reinforcement as they are inexpensive, low density, accessible, and reduce environmental pollution. This study focuses on investigating the effect of alumina (Al2O3) and rice husk silica (RHA) as reinforcement on the recycled aluminium alloy (AA7075) chip by cold compaction method. The aluminium AA7075 chip was reinforced with 0.5 wt.%, 3.0 wt.%, 5.5 wt.%, 8.0 wt.% and 10.5 wt.% of RHA with the particles size of 63 µm, and alumina powder with the particle size of 1.0 µm, 5.0 µm and 35.0 µm. The aluminium matrix composite (AMC) samples were tested by mechanical tests. The hardness and compression strength of AMCs decreased with increasing RHA content. The hardness and compression strength of AMC are higher compared to pure aluminium, with an increment of 106.45% and 12% respectively. The best composition for the reinforced composite sample was obtained at 0.5 wt.% RHA, while 5.0 µm Al2O3 provides superior mechanical properties compared to other parameters. Based on the investigation, the addition of RHA and alumina has good potential to improve the mechanical properties of aluminium. [ABSTRACT FROM AUTHOR]

Liquid Crystal (LC) research has steadily shifted its attention to inorganic alignment technology. In this article, Silicon Dioxide (SiO2) Nanoparticles (NPs) coating has been used as an alignment layer on Indium Tin Oxide (ITO) glass substrates using the thermal evaporation technique. Furthermore, Electro-Optical (E-O) and morphological properties have been measured for different concentrations of SiO2 NPs thin film induced homeotropic aligned LC cells. The polarized optical microscopic morphological study showed the black texture in the off-state at 0V, however uniform bright white texture was detected on applied voltage at on state, under crossed polarizer and analyzer. Further, the confirmation of homeotropically aligned LCs was attained by observing the maltease cross under conoscopic view. Consequently, the E-O and morphological results showed that the operating and threshold voltages were reduced with the increase of concentration of SiO2 NPs in the thin film deposited on the substrates and obtained the improved Contrast Ratio (CR). [ABSTRACT FROM AUTHOR]

Thermal insulation, drug delivery, adsorption of spilled oil, and self-cleaning windows are the main applications of silica aerogel. In this work, the production and characterization of superhydrophobic silica aerogels doped with Rhodamine B dye are presented. And investigating the effect of doping on some physical properties and chemical structures has been studied. In the preparation, two procedures were used, with the main goal of obtaining a product with the best characteristics in the shortest amount of time. The first method is known as RH1 and RH2. RH1, the modification procedure when the doped sol is converted to gel RH2, begins with the changed solution being added to the sol. The structural, spectral, and morphological properties were investigated using FTIR, BET, and FESEM, as well as EDS analysis. Results show that RH1 samples have the highest contact angle (146°) surface area (899 m2/g), and lowest particle size compared with RH2 samples. Except for the apparent increase in density, the investigation demonstrates that Rhodamine B dye can advance the structural properties of silica aerogel. This study found when n-hexane is mixed with the sol before converting to gel, the aerogel has better specifications and more improvement than the modified surface that's modified after converting to gel. [ABSTRACT FROM AUTHOR]

The aim of the project is to improve the V-I characteristics of a drain current of La2O3 and compared with SiO2 material by reducing the gate voltage of planar CNTFET. The Lanthanum oxide and silicon dioxide materials were chosen as a group having 20 samples per group respectively. A DFT tool is used to perform the drain current by changing gate v oltage. The independent T-Test was done which reveals that the Lanthanum oxide of a CNTFET (P = 0.222) was found significant compared with the Silicon dioxide material of CNTFET. The analysis found that Lanthanum oxide appeared to have significantly better efficiency than silicon dioxide from drains current. While La2O3 (mean = 105607.2085) has better V-I characteristics of a drain current compared with silicon dioxide (mean = 67911.11838). [ABSTRACT FROM AUTHOR]

The purpose of the project is to advance in some way the electrical characteristics of Aluminum Oxide (Al2O3) Omega FinFET over conventional Silicon dioxide SiO2 material by varying the thickness and its range to be 1nm to 20 nm. DFT tool is used to perform the VI characteristics. The method was performed for the 20 samples per group i.e, Aluminum Oxide (n=20) and SiO2 (n=20). For the two samples, the sample size is the same for the control and experimental group. By adjusting the thickness of the Gate and Drain voltage in the Omega FinFET using the various materials of Al2O3 and SiO2, we were able to get the desired results. Maximum accepted error is fixed is 0.05 and beta is 0.2. From the analysis, Aluminum Oxide (Al2O3) shows better performance with the variations in band gap and dielectric constant with values of 9.8 eV and 7.6 than the SiO2 band gap and dielectric constants with the values of 3.9 eV and 8.4. The significance value is p<0.05. The conventional Aluminum Oxide (Al2O3) Omega FinFET is significantly higher when compared to SiO2 based omega FinFET. The significant value is (P=0.036). [ABSTRACT FROM AUTHOR]

This experimental inquiry aims to develop a novel use of Silicon dioxide (ZnO) nanofluid in flood freezing instead of traditional coolant to boost the rate of removal of material in CNC turning of Inconel 800. While the samples throughout the intervention group are processed employing Silicon dioxide (ZnO) nanofluid, the samples with in control group are machined using conventional coolant. The nanoparticle size of little under 5nm and a concentration of 4percentage silicon dioxide (ZnO) nanopowder were preferred. The required sample size was found to be 24 (12+12). Using G-Power 0.80 as well as an alpha of 0.05, the sample size was determined. The Taguchi standard experimental design was performed by L16. [ABSTRACT FROM AUTHOR]

Increasing the material removal rate in CNC Turning of Inconel 800 with a novel application of Silicon dioxide (CuO) nanofluid in flood cooling instead of Conventional coolant is the aim of this experimental study. Materials and Methods: The control group's samples are machined with conventional coolant and the intervention group's samples are machined with Silicon dioxide (CuO) nanofluid The 4% Silicon dioxide (CuO)Nanopowder concentration and Nanoparticle size less than 5nm size were preferred. The required minimum total sample size was calculated as 24 (12+12). The sample size calculated with the settings of G-Power 0.80 and alpha of 0.05. The near higher Taguchi standard experimental design L16 executed. The material removal rate observed for setting of 32 (16+16) different input combinations. The independent key process variables (inputs) included were: cutting speed, rotational speed, its feed rate, Coolant employed and depth of cut. Results: The group's observations were validated and analysed statistically with SPSS software and found significant (Significant value 0.041<0.05). The output of the proposed method is analysed with ANOVA and also ranked the independent variables based on their influence in the objective. The input parameters optimized (local solution). Mathematical model developed to predict the response of MRR with respect to input levels (global solution). Conclusion: Within the limitations of this study, material removal rate was significantly improved with use of CuONanofluid in wet machining. That is, CuONanofluid improved 45.05% of material removal rate in CNC Turning of INCONEL 800 than conventional coolant. [ABSTRACT FROM AUTHOR]

The effects of rice husk silica (RSi) and vinyltriethoxysilane (VTES) content on cure characteristics, mechanical, morphological, and thermal properties of natural rubber (NR) composites were studied. NR is a renewable material that is widely used in a variety of products. In the production of NR products, several fillers may be used to manufacture a product with the desired properties. However, the majority of fillers are non-environmentally friendly and incompatible with rubber. To solve these issues, rice husk ash (RHA) from biomass power plant was used to produce silica for use as a filler and VTES was used as a compatibilizer. The cure characteristics, mechanical, morphological, and thermal properties of NR/RSi composite at various RSi contents (0, 5, 10, and 20 phr) were studied. The optimal RSi content was used to study the effect of VTES content on mechanical, morphological, and thermal properties of NR/RSi/VTES composite. The increasing RSi content improves mechanical and thermal properties of NR/RSi composites with the optimal RSi loading at 20 phr. While the mechanical properties of NR/RSi/VTES composites show the optimal VTES loading at 0.5 phr. [ABSTRACT FROM AUTHOR]

Graphene is produced using green synthesis approaches from rice husk, called rice husk-derived graphene (GRHA). Due to the high silicon content compared to carbon in raw rice husks, this research will add sodium hydroxide (NaOH) treatment to reduce silica in the resulting GRHA, commonly known as desilication. Rice husk ash (RHA) was mixed with NaOH solution by stirring at 80 °C for 3 hours, followed by filtering, washing, and drying. Variation in NaOH concentration is 0.5, 1.0, and 1.5 M to study the optimal one added between the carbonization and activation at high temperature with potassium hydroxide (KOH). EDS spectra confirmed that the NaOH treatment could reduce silica, and the most optimal concentration was found at GRHA-1.0, as it possessed the highest carbon content of up to 80.27%. SEM images also showed a crumpled structure of layered graphene with a thickness of several nanometers. XRD patterns showed that the three samples still contain silica with a high degree of crystallinity. It is due to the thermal treatment, which is also responsible for converting silica from amorphous to crystalline. This methodology is a promising way to increase the added value of rice husks with a cost-effective process while reducing the wasted as an environmental burden. [ABSTRACT FROM AUTHOR]

Cloud seeding materials for weather modification used today have been around for many decades. This paper is working to design a new cloud seeding material with optimal properties to ensure water vapor condensation occurred effectively and maximize the rainfall achieved by using nanotechnology. The nanotechnology changed the surface of the material to make it more reactive at a lower relative humidity so the water can be absorbed easily and increase the probability of forming water droplets. Due to this reason the present research is focused on the developing sodium chloride (NaCl) nanoparticles fabrication using silica (SiO2) as a coating and anticaking material and then investigated the effect on the particle size reduction of sodium chloride. In this study we have successfully developed and identified sodium chloride (NaCl) nanoparticles fabrication as a potential new cloud seeding material. By using jet milling method for particle size reduction and varied SiO2 percentage (wt%) in the mixture and the cycling number of jet milling parameters has resulted NaCl/SiO2 submicron particles size distribution. Measurement on the jet milling results by a particle size analyzer (PSA) instrument showed that material with 3% SiO2 (wt%) addition and 3 (three) times jet milling cycling were found to contain NaCl/SiO2 mixture with less than 100 nm size distribution [ABSTRACT FROM AUTHOR]

Green tire technology fiercely adopted ecofriendly silica as a reinforcing material in the place of potentially dangerous carbon black, which has higher rolling resistance and fuel consumption. The use of industrial nano silica (NS) as a beneficial and affordable green filler in vulcanizates of natural rubber (NR) and natural rubber latex (NRLX) containing carboxyl-terminated liquid natural rubber (CTNR) as a polymeric plasticizer and coupling agent is discussed in this research. CTNR, a possible plasticizer in NR and NRLX vulcanizates, can be made by a photochemical reaction combining maleic anhydride and depolymerized natural rubber. As compared to amorphous silica filled vulcanizates, the features of the industrial nano silica filled and CTNR incorporated NR and NRLX vulcanizates (NS NR-CTNR & NS NRLX-CTNR) were studied. The improved tensile properties, hardness values, ageing resistance, and water resistance of the NS NR-CTNR and NS NRLX-CTNR vulcanizates can be attributed to the higher bound rubber content facilitated by the improved rubber and the nano-sized filler interaction as well as the ionic cross linking between the-OH group in silica and the-COOH group in CTNR as well as the co crosslinking of CTNR to NR. [ABSTRACT FROM AUTHOR]

In this study, the mechanical properties (impact test and flexural strength) for epoxy composite, and polymer-based composites were prepared by hand casting method. The composite material was prepared from epoxy resin as a base material supported by nano and micro materials from silica (Sio2) and titanium oxide (Tio2) with different weight fractions, the percentages of addition of nano titanium oxide (Ep+nano Tio2) with weights were (0.25, 0.50, 0.75, 1, 1.25) grams, respectively. The percentages of addition of nano-silica (Ep+nanoSio2) with weights: (0.1, 0.2, 0.3, 0.4, 0.5) grams, and the percentages of addition of micro titanium oxide (Ep+ microTio2) with different weights (0.3, 0.6, 0.9, 1.2, 1.5) grams, and the percentages of addition of micro-silica (Ep+microSio2) were (0.3, 0.6, 0.9, 1.2, 1.5 (grams) Weight fractions, and the flexural test (three-point) and the impact test were conducted on them. The results of the research showed that the values of the flexural strength of nanomaterials increase with increasing weight, as well as the impact resistance increases with a non-linear relationship with increasing the weights of the nanomaterial. [ABSTRACT FROM AUTHOR]

Aluminium alloys are more widely used in the automotive and aerospace industries. Aluminium alloys have good weldability characteristics and light in weight. The depth of penetration is the main factor to improve the weld joint efficiency. This research work aimed to study the weld characteristics and depth of penetration at various welding process parameters like voltage, current, and gas flow rate. Activated Flux TIG (A-TIG) welding process is carried out on AA 5083 by applying different activating fluxes. The silicon dioxide and titanium dioxide fluxes are applied as activating fluxes on the workpiece to study the metallurgical and mechanical properties of the weld joints. The impact strength and hardness of the weldments are measured. It is found that ATIG welding of Aluminium alloy with SiO2 flux has more depth of penetration than the TiO2 flux and without flux. The grain structure over the heat-affected zone (HAZ) and the welding zone is observed. The fine grain structure is observed with SiO2 flux which leads to an increase in strength of the weldments. [ABSTRACT FROM AUTHOR]

This current study implies the modification of nano silica in two possible ways which prevent agglomeration and results in proper homogenization of nano silica (NS) particles and its application in enhancement of mechanical properties of a coating. NS was first modified by silane coupling agent by adding equal ratio of nano silica and aminipropyltrimethoxysilane (APTES) and dissolved in toluene and was stirred for 12 hours. Then was centrifuged at 3000 rpm for 10 minutes and washed with ethanol twice. It was then placed in a vacuum oven for 8 hours at 70°C and the modified NS was synthesized. The NS particles are again modified in a different method by using triallyl isocyanurate (TI). NS was first dried at I00°C for 24 hours. NS and isocyanate were taken in ratio 1:0.8 and dissolved in toluene stirred for 12 hours. Then the solution was centrifuged at 4000 rpm for 15 minutes and washed twice with ethanol. It was dried in a vacuum oven for 8 hours at 70°C. The modification process was confirmed by doing FTIR and XRD analysis. Water and ethanol dissolvability as well as grafting % were also studied. Both the modified NS particles were added in acrylic-based polyurethane (PU) coating at an optimized weight% of 0.5 wt% and the enhancement in mechanical coating characteristics were observed by running cross-cut tape test and abrasion test. [ABSTRACT FROM AUTHOR]

Three different nanomaterial, black iron oxide (Fe3O4), copper oxide (CuO), and silicon dioxide (SiO2), are used in various volume percent concentrations (0.1, 0.2, 0.3, 0.4 and 0.5) with water (base fluid) as a cold (nano) fluid, flowing with five different flow rates (100, 150, 200, 250 and 300 cm3/s) in outer tube countercurrently to the hot fluid (water), which is flowing constantly at flow rate of 50 cm3/s in the inner tube of double pipe heat exchanger. There were advantageous effects of adding the nanomaterials to cold fluid, where led to improvement in heat transfer rate and heat transfer coefficient, which was with Fe3O4 the greater than CuO and SiO2 respectively, but with progressive diminution in their slopes. The average percent improvement in heat transfer rate was 12.23, 18.66 and 27.83, whereas for heat transfer coefficients was 15.12, 23.34 and 35.51 with SiO2, CuO and Fe3O4 respectively at concentration of 0.5 vol.%. [ABSTRACT FROM AUTHOR]

This work refers to the purification process of silica rock, particularly through the removal of iron and other trace elements from the silica rock. In the present study, acid leaching treatment was employed as an optimal solution to purify silica rock. The purpose of this study is to improve the quality of silica rock via leaching method. Variable sulfuric acid concentrations (0.125 - 0.410 M) and leaching time (60 – 120 minutes) were considered, in addition to constant speed of agitation (150 rpm) and temperature (60 °C). The content of silica in silica rock after leaching was determined using gravimetric result. Sulfuric acid was found effective in improving the purity of SiO2, where 99.85% purity was successfully achieved at 0.250 M acid concentration. The high purity silica is deemed as a valuable raw material for silicon production and glass making application in particular. [ABSTRACT FROM AUTHOR]

We conducted the desalination process of seawater into clean water using silica produced from natural sediment. The sediment contains Si-O-Si and Si-OH groups in the silica to absorb NaCl substances in the seawater. Silica from natural sediment was purified from heavy metals using acid reflux and then measured physical and chemical characterization. The XRF analysis, calcination process, FTIR and AAS analysis were investigated to produce and optimize silica from a sediment sample. The application of silica was applied to absorb NaCl in Prigi Seawater. The results indicated the white silica adsorbent had a typical peak stretching vibration of Si–OH groups visible at wave number 3200-3400 cm−1 as the potential situs of Na+ ion adsorbent. The effective temperature in the produced silica sediment was at 800°C with adsorbed Na+ ion on the artificial seawater of 25 mg/L (16.7%) while the Prigi seawater sample was 60.8 mg/L (10.7%). The produced silica can reduce the salt content of Prigi Seawater. [ABSTRACT FROM AUTHOR]

Coffee's volatiles was extracted and adsorbed in a silica cellulose matrix. Silica from rice husk ash and cellulose from nata de coco was made adsorbent, from which volatile compounds can be adsorbed and released. Extracts from Arabica coffee types were applied. The objectives were to make an environment-friendly air freshener from coffee extracts and silica cellulose materials. GC-MS was employed to determine the volatiles released at 1st, 2nd, 7th and 14th days of adsorption time. The results showed interesting profiles of Arabica coffee with organic acid and ester components. A study about the surface dynamics of certain volatiles is underway. [ABSTRACT FROM AUTHOR]

The observation of lotus leaves wettability behavior can be applied in various application. Silica has a good characteristic for hydrophobic stability. This objective of the study was to create a hydrophobic surface from a composite material of SiO2 filler and polydimethylsiloxane matrix. Silica is obtained from the purification of natural sand Bancar, Tuban, East Java. The variations of phases used were silica quartz (SQ), silica amorphous (SA), and silica cristobalite (SC). Silica cristobalite (SC) was obtained after calcinate SA at temperature 1200°C for 2 hours. The results of this research showed that the highest contact angle of hydrophobic surface is 126.4° (hydrophobic) at 400°C and the lowest is 72.4 (hydrophilic) at 500°C. The water contact angle (WCA) of the as-prepared hydrophobic coatings reached as high as 148.24° (WCA=148.24°) by applying of the PDMS/SA coating. The transmittance of coatings reached as high as 100%. [ABSTRACT FROM AUTHOR]

A study on the extraction of silicon dioxide (silica) based on biomass was carried out successfully. The biomass used in this study was the palm shells and fibre. The study started with the preparation of bottom ash waste extraction and then continued with the sodium silicate solution from bottom ash waste and the preparation of precipitated silica. The preparation of precipitated silica was carried out with bottom ash dissolved with (1 N, 3 N or 4 N) of NaOH, heated at a temperature of 105 °C, precipitation of silica sol-gel with 3 N H2SO4 to pH=7 with an ageing time of 18 hours. Based on the FTIR characterization test of palm oil shells and fibre, the silica has the absorption peak at wave number 2,901.39 cm−1; 2,167.18 cm−1; 2095.38 cm-1; 1,642.30 cm−1 and 1,408.37 cm−1 that indicated the presence of stretching vibrations of the hydroxyl (-OH) functional group of water (H-O-H) silanol functional group (Si-OH). The absorption peak at wave number ±1100 cm−1 indicated the presence of the strongest bond of the siloxane functional group (Si-O-Si). The absorption peak was 786.24 cm-1; 634.43 cm−1 and 609.85 cm−1 indicated the presence of stretching and bending vibrations of the Si-O functional group of the siloxane (Si-O-Si) functional group. From this NaOH, the highest weight was obtained at NaOH 4 N, 36 grams of precipitated silica from 50 grams of bottom ash was produced. [ABSTRACT FROM AUTHOR]