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Using no-core optical fiber (NCF) and conventional single-mode fiber (SMF), this research needs to increase the sensitivity of temperature and relative humidity measurements for radiology device applications. Operating on the Mach-tender Interferometer (MZI) principle, the sensors make use of surface plasmon resonance. Traditional sensing technologies sometimes confront difficulties in reaching high sensitivity and accuracy, especially in demanding environments like radiology facilities. In order to increase the sensitivity of four relative humidity sensors constructed from SMF, TNCF, and SMF, a 2 cm NCF segment was incorporated. To enhance sensitivity, the sensors have been coated with a variety of substances, such as gold nanoparticles (AuNPs), silica nanoparticles (PVN/PVP), and a layer-by-layer technique. The sensor coated with AuNPS exhibited the greatest sensitivity with respect to temperature, attaining 0.486 db/°C. The fiber optic sensors that have been developed exhibit great potential for utilization in biomedical and environmental domains. Experimental tests are carried out to assess the performance of the proposed sensing system, including sensitivity, accuracy, and reaction time. [ABSTRACT FROM AUTHOR]

This study was carried out to determine the Flexural Strength of (ABS) Acyroonitrile Butadiene Styrene and the Flexural Strength of (ABS) composites with silica nanoparticles. There were 20 specimens for each group of sample that served as an experimental group that had ABS with filler and a control group comprised of ABS without filler. The sample size was decided at the 80% power, at 0.05 alpha per set. The base materials incorporated were Acrylonitrile Butadiene Styrene with the Silica nanoparticles filler added. This is testified by the fact that the Flexural Strength of ABS Composite in contrast with ABS Composite with 2% volume fraction of novel silica nanoparticles filler was higher. The P value was determined as 0.00 (p<0.05), which is statistically significant and denoting a difference between the two groups. Statistically, the value of ABS with 2% filler was also seen as an observation variable. Hence, the conclusion being that the superior flexural strength of ABS with Novel Silica nanoparticles fillers composite was reached without the introduction of Novel Silica nanoparticles fillers. Indeed the findings are restricted by the small sample size and laboratorial conditions. [ABSTRACT FROM AUTHOR]

In this study, the removal of pharmaceutical waste products from aqueous solutions has been investigated using oil palm frond based mesoporous silica nanoparticles (MSN) synthesized via modification of sol-gel process. The removal and adsorption study using MSN were tested toward three type of pharmaceutical product which are paracetamol, ibuprofen and aspirin. The performance study was performed and shown that ibuprofen give the highest removal percentage up to 97%, followed by paracetamol and aspirin with the percentage removal of 67% and 50% respectively. The result was confirmed that mesoporous silica nanoparticle (MSN) might be utilised as a low-cost adsorbent with excellent pharmaceutical product removal in aqueous solution. [ABSTRACT FROM AUTHOR]

Utilization of nanoparticles in oil and gas sector has gained a significant interest. Silica nanoparticles is often considered as a promising chemical to improve the Enhanced Oil Recovery (EOR) process. The objective of this work was to provide a mini review to address the effect of silica nanoparticles addition in a chemical EOR. In this work, we have reviewed the influence of nanoparticles to reduce Interfacial Surface tension (IFT), to alter wettability, to reduce oil viscosity, to improve fluid rheology, and to alter structural disjoining pressure. We expect that this review may provide a useful guidelines for the development of silica nanoparticles in Indonesia. [ABSTRACT FROM AUTHOR]

The perfect adsorbent should be simple to make, low-cost to create and have a high adsorptive capability for adsorbents. We have scientifically documented all research efforts on Mesoporous Silica Nanoparticles (MSNPs) in this review paper on (MSNPs) DNA adsorption and release, production, and applications. Furthermore, we have contrasted the adsorption capacities of variously modified mesoporous silica nanoparticles. Additionally, by using a cool (50°F) atmosphere synthetic approach and a dual surfactant system, several measures of silica and nanoparticles with regulated distances between 75 to 250 nm, and the same (20.0 nanometers) hole size were made. The material's final textural characteristics are attained by a further hydrothermal treatment that produces tall hole amount (MSNPs) by finally the greatest hole entry length of the hole or width (17.0 nanometers) (20 nm) until that time noted. Mesoporous Silica Nanoparticles (MSNPs) may perform a wide range of drug-delivery functions and Mesoporous silica nanoparticle applications. [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]

Exploiting oil reserves has been a priority in recent years due to the high demand for energy. One method proposed to overcome the drawbacks of standard chemical enhanced oil recovery is the usage of emulsion flooding. Enhancing emulsion stability is important to ensure its performance. Moreover, the viscosity should be maintained to ensure its capability in pushing the reservoir oil. Synergistic effect between surfactants and nanoparticles has been suggested to achieve the intended viscosity and stability for emulsions. This article reviews this effect between nonionic surfactant (Triton X-100) and silica nanoparticles (SNP) in enhancing the emulsion viscosity and stability with varying the weight ratio of SNP to Triton X-100. The apparent viscosity of the emulsion was measured, and bottle test was used to investigate emulsion stability. It was observed that emulsion viscosity has peaked to 87 cP with weight ratio of 0.5 compared to 12 cP with no added SNP. Moreover, the 0.5 weight ratio of SNP to Triton X-100 was proved to be the most stable emulsion among the investigated samples in this article; where emulsion phase height percentage has experienced a decrease (measure of emulsion stability) up to 40% compared to 55% decrease in the case of using Triton X-100 surfactant only. This has shown that nonionic surfactant and nanoparticles (NPs) with the usage of a proper weight ratio can be used in enhancing the emulsion viscosity and stability. Hence, these emulsions could be used applications of utilizing emulsion as a flooding method where the stability of the emulsion and its viscosity is crucial. [ABSTRACT FROM AUTHOR]

Nowadays, engineers generally prefer phase change materials (PCM) for study and for usage as heat storing materials. This is due to these materials accumulate and deliver a significant quantity of latent heat throughout the melting and freezing processes, which includes transitioning from one phase to another. Engineers may employ this feature of PCM in a variety of ways, including heat energy storage, which allows engineers to store heat or cooling from one operation and use it later or in multiple places. To boost the thermal conductivity of PCM, a heat conductive component viz., nanoparticles is included; these materials are referred to as n-PCM. To investigate the characteristics of produced composites, characterization tests such as transmission electron microscopy (TEM), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and thermal conductivity tests were performed. The ideal features of n-PCM, its thermophysical properties, as well as the obstacles and future directions of this novel material are discussed in this paper. This study examined and presented various applications and basic properties of n-PCM with alumina/silica. This investigation enhanced the thermal conductivity of n-PCM. This n-PCM demonstrates the enormous potential inherent in thermal energy storage systems. [ABSTRACT FROM AUTHOR]

The study aims to evaluate the roundness error in drilling of Novel Hybrid glass/luffa/epoxy composites by addition of silica nanoparticles in comparison with plain luffa natural fiber composites. he plain luffa natural fiber composite reinforced with epoxy/glass fiber taken as control group(N=20). The luffa/glass material is reinforced along with an epoxy matrix mixed by addition of silica nanoparticles filler taken as an experimental group(N=20). The control group and experimental group are conducted by using a hand lay-up method. Roundness in drilling is conducted as per ASTM standards. Roundness error during drilling was calculated by using the imageJ software and the damaged area was compared for both groups. The G power test was used to assess the number of samples in each group. Glass fiber with plain luffa without filler epoxy composite laminate exhibited a decrease of 64.66% in damage area than the 2% volume fraction of silica nanoparticles luffa/glass laminates. The significant value of P is 0.043 (<0.05). Within the limits of study, glass fiber/luffa fiber reinforced with epoxy material without filler exhibits a significant reduction in the roundness error during the drilling process. [ABSTRACT FROM AUTHOR]

Nanoscale drug delivery systems have been found to increase drug loading efficiency and avoid the body's immune response. In this research, magnetic mesoporous nanosilica was developed as a drug carrier by utilizing Kulon Progo iron sand's natural resources as the material. Magnetic mesoporous nanosilica was synthesized by the coprecipitation method using NH4OH as the precipitant. The synthesis was carried out in three stages to see the effect of adding silica and surfactant at each stage. The first stage was Fe3O4 synthesis from iron sand. The second stage included the synthesis of Fe3O4@SiO2 by adding Tetraethyl Orthosilicate (TEOS) as the silica precursor. The last stage was the synthesis of Fe3O4@SiO2−CTAB, in which Cetyltrimethylammonium Bromide (CTAB) was the surfactant used. Each of the materials synthesized was characterized using X-Ray Diffraction (XRD) and Energy Dispersive X-Ray (EDX). The crystalline size calculation results using XRD data show that the particles are in nano size, the particle size of Fe3O4@SiO2−CTAB nanoparticles obtained 6.77 nm. Simultaneously, the % crystallinity also shows better crystal quality results after the addition of the two compounds. This influence can also be seen from the EDX analysis, where Fe decreases and new compositions, namely Si and Br, are present. [ABSTRACT FROM AUTHOR]

In today's world, scientists are focusing on developing new materials that provide lower costs, environmental sustainability or increased capabilities. One way to develop new materials is to modify conventional types already established in industry. An example is the development of composite materials with different types of matrices or fillers. In the last two decades, scientific work has mainly focused on the incorporation of nanofillers into conventional and used matrices such as resins, thermoplastics such as polyethylene or others. One of the issues in performing these modifications is the process of incorporation of nanoparticles into matrices, which is problematic in many aspects. This paper focuses on the effect of silica nanoparticles with different incorporation methods into polyester-imide resin (PEI). The main objective of this experiment was to find the optimal way of the process of mixing nanoparticles with the resin. Thus, this optimal process can be used in follow-up experiments to develop a new type of insulating material for high voltage applications. In this experiment, conventional dielectric parameters such as relative permittivity, dissipation factor, volume resistivity and dielectric strength were diagnosed. [ABSTRACT FROM AUTHOR]

As the era of 'easy oil' is coming to an end the oil and gas industry is being propelled towards the state of the art nanotechnology to overcome challenges. On one hand the ease with which the hydrocarbon was extracted is getting reduced day by day while the demand keep on increasing exponentially. The next step would be to provide the required results along with mitigating the risk associated. The recent advancements and applications of the nanotechnology in the oil and gas industry are extremely diverse and can lead to open new frontiers in the exploration and development of the various hydrocarbon bearing sedimentary basins. The aim of the current paper is to discuss the advancements and applications of nanotechnology in enhancement of oil and gas production in a cost economic way. This analytic study provides the detailed information of the implementation of nanoparticles such as silica, Graphene, Carbon nanotubes which can improve well productivity. [ABSTRACT FROM AUTHOR]

The silica nanoparticles have been successfully synthesized from sugarcane bagasse using the sol-gel method. Sugarcane bagasse contains abundant silica, so it can used as an alternative source of silica nanoparticles. Sugarcane bagasse was calcined at 650 °C for 2 hours, then it was extracted using NaOH to obtain sodium silicate solution. The solution was titrated with HCl for gelling process. The synthesized of silica nanoparticles from sugarcane bagasse were characterized using FTIR and XRD. Based on the XRD characterization, the results showed that the silica had an amorphous phase, and the FTIR spectra has siloxane and silanol groups. The synthesized silica nanoparticles have an average size of 53 nm which was calculated using Scherrer Formula. From the data obtained, sugarcane bagasse can used as a source of silica nanoparticles. [ABSTRACT FROM AUTHOR]

ZnO nanoparticles have interesting characteristics and potential applications in various lines of life. However, its size and weak compatibility can cause aggregation. Therefore, ZnO nanoparticles are composited with silica aerogel as a buffer matrix to enhance the potential function of ZnO to form ZnO/silica aerogel nanocomposites. The nanocomposite was synthesized using the molten salt method by involving the main precursor ZnCl2 which was calcined at 450 °C together with a silica aerogel buffer matrix in various calcination time variations. The success of synthesis based on FT-IR analysis is shown by the presence of vibration groups of silanol (Si-OH), siloxane (Si-O-Si), and Zn-O vibrations from the ZnO lattice. The inclusion of ZnO nanoparticles in the silica aerogel matrix is indicated by the presence of a peak in the XRD test that relates to ZnO standard peak (JCPDS No.36-1451). The analysis results based on X-Ray Fluorescence showed that the optimum percentage of ZnO formation in the silica matrix occurred at 40 minutes of calcination time. Mapping of the synthesized results showed the presence of ZnO nanoparticles scattered on the silica aerogel matrix. ZnO nanoparticles experienced a fairly homogeneous distribution on the silica aerogel matrix with 70% of Zn composited with the size of the nanocomposite particles produced ranging from 25-72 nm. [ABSTRACT FROM AUTHOR]

The present work is concerned with the preparation of Nano silica from Iraqi sand and studies the influence of different organic and inorganic acids on characteristics using the chemical precipitation method. The materials included silica - sand, sodium hydroxide, sulfuric acid, hydrochloric acid, acetic acid, and distilled water. Three samples of silica nanoparticles were collected and characterized by X-Ray Diffraction (XRD). Structure analysis revealed that all the samples of Nano silica powder had an amorphous structure in nature. They also have a wide peak at 2Θ= (22 - 23°) for each sample. The particle size distribution was measured using an Atomic Force Microscope (AFM), and the results revealed that the best average diameter was 61 nm, with a dimension range of 35-80 nm. While Brunner Emmett Teller (BET) for three samples analysis confirms a high surface area of approximately 560.86 m²/g. The inclusion of hydrogen-bonded silanol groups (Si–O–H) and siloxane groups (Si–O–Si) in the Fourier Transform Infrared spectra (FTIR) experimental results demonstrated the high purity of silica nanoparticles. Thermogravimetric Analysis (TGA) study findings demonstrated the thermal stability of the Nanosilica by a lower overall weight loss of 11.74%. [ABSTRACT FROM AUTHOR]

In this work, varying sizes of silica nanoparticles (∼12 nm and 40 nm) are dispersed into room temperature ferroelectric liquid crystal (KCFLC 10R). Dielectric and optical studies have been done to explore the effect of nanoparticle's size on the properties of host material. Variation in the energy band gap with the dispersion of silica nanoparticles is noticed.Frequency dependence dielectric behavior in the frequency range 20Hz-10MHz is also studied in pure and silica doped samples. [ABSTRACT FROM AUTHOR]

Enhanced Oil Recovery (EOR) is one of promising method to increase the national oil production in Indonesia. Chemical EOR by adding surfactant to reservoir may decrease the interfacial tension (IFT) values, alter the wettability of rock and hence may increase the production. In this work, the influence of Silica Nano Particle (SNP) addition to the IFT of commercial EOR surfactant has been investigated. We found that without addition of surfactant, the liquid sample with only containing SNP gave high IFT value at ca. 10-1 dyne/cm. Addition of surfactant has decreased the IFT and variation of surfactant concentration gave the value of CMC value after dilution of 10x. The effect of adding silica nanoparticles (SNPs) to commercial surfactants showed that addition of SNP may decrease the IFT value from 3.10-3 dyne/cm to 5.10-4 dyne/cm. The photograph from IFT measurement also indicated that SNP gave more stable mixture during IFT measurement. By varying the volume of SNP added to the system, it was found that finding optimum volume is important as excessive addition of SNP may result in higher IFT values. This study may provide a further pathway to investigate the influence of SNP addition to large scale EOR Project in Indonesia. [ABSTRACT FROM AUTHOR]

Gadolinium oxide-doped mesoporous silica nanoparticles (Gd2O3-MS) were synthesized using CTAB as surfactant template via sol-gel method. The generated Gd2O3-MS nanoparticles were characterized for phase using X-ray diffraction (XRD) measurement, functional groups were determined by Fourier-transform infrared spectroscopy (FTIR), morphology and element composition were revealed by scanning electron microscope (SEM) and Energy-dispersive X-ray (EDAX) analysis, nitrogen adsorption-desorption isotherms, and magnetic properties were conducted by vibrating-sample magnetometer (VSM). The analysis results confirm that Gd2O3-MS nanoparticles were successfully synthesized in spherical form with diameter sized∼90 nm. Gd2O3-MS nanoparticles has the BET surface area value of 468.2 m2/g with total pore volume of 0.5867 ml/g and three kind of pore size distributions, namely, 1.8 nm, 2.9 nm and 3.3 nm. These Gd2O3-MS nanoparticles possess magnetic and mesoporous properties that may act as contrast agent and can accept organic molecules (for drug delivery) with further research. [ABSTRACT FROM AUTHOR]

Silica has entrenched surface chemistry which allows for the surface functionalization with various functional groups, including those of biomolecules. In this study, the aim is to modify fluorescent natural silica nanoparticles (FSNP) with E.coli antibody. The precursor for fluorescent natural silica-based nanoparticles (FSNP) was obtained from a silica precipitate of geothermal power plant in Central Java, Indonesia. This offers a more cost-effective and environmentally friendly route towards the preparation of such nanomaterials. FSNP was synthesized using the sol-gel method to produce impurity-free fluorescent nanoparticles, then activated the groups to conjugate with E. coli antibodies. The surface functionality of the amines is obtained by reacting FSNP with an aminosilane crosslinker (APTES). To produce aldehyde functionality, it is further treated with glutaraldehyde. These aldehyde groups react with the amine groups of biomolecules such as antibodies to form amine bonds. Based on the BraunerEmmett-Teller (BET) analysis, the average surface area is 134.32 m2/g FTIR results showed the formation of NH2 groups after modification of FSNP with APTES at a wavelength of 1635 cm−1. The intensity of FSNP modified FSNP and APTES measured using fluorescence spectroscopy at the FSNP intensity was 688,430 a.u while the intensity of the APTES modified FSNP was 450,474 a.u. The approach of conjugating E.coli antibodies to fluorescence natural silica-based nanoparticles via the APTES crosslinker opens up the possibility of future use of the system as a biosensing platform, particularly the detection of E. coli. [ABSTRACT FROM AUTHOR]

Small Angle Neutron Scattering (SANS) experiments have been carried out to investigate the modification in the structure of nanoparticle and mixed cat-anionic surfactants complex with respect to individual surfactant (cationic or anionic). In absence of nanoparticles, individual surfactants (cationic DTAB or anionic SDS) self-assemble to form micelles and their mixed system forms large unilamellar vesicles. There is no physical interaction of anionic surfactant micelles with anionic silica nanoparticles, whereas cationic surfactant micelles are strongly adsorbed on anionic nanoparticles leading to aggregation. The vesicles of mixed surfactant system rearrange themselves to form a bilayer around the nanoparticles. Contrast variation SANS is employed to get the structural parameters of these multi-components systems. [ABSTRACT FROM AUTHOR]

Silica nanoparticles are one of the nanomaterials that are used quite extensively because of some of their unique characteristics. The synthesis of silica nanoparticles is usually made from tetraethyl orthosilicate (TEOS) as the precursor but because of the price is quite expensive it will be replaced with sodium silicate. In this study silica nanoparticles will be synthesized by using Sol-Gel and Heat Injection Method by varying the temperature operation. Ammonia and ethanol solutions are the solvents which will be injected by sodium silicate. The result silica nanoparticles were characterized to know crystal structure and morphology using X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). In this study, the structure formed from nanosilica powder is amorphous. The analysis results show that the shape of nanosilica in general is spherical. [ABSTRACT FROM AUTHOR]

Silica-coated CuFe2O4 nanoparticles were synthesized by the conventional stöber process. Tetragonal structure of CuFe2O4 was retained even after silica coating with crystallite size ~ 14.8 nm. A small characteristic broad hump was observed in the XRD spectrum in the range 20-25°, due to the presence of amorphous silica. Spherical formation of nanoparticles and presence of silica were also confirmed by Transmission Electron Microscope (TEM) as well as Fourier Transform Infrared (FTIR) spectroscopy. Cell-Viability (%) values of uncoated and silica-coated nanoparticles, as analyzed by Trypan blue exclusion assay on C6 cells were obtained to be 67.7% and 72.5%. Effect of silica coating on the optical properties was studied at different concentrations of silica. In UV-Vis plots, the maximum absorbance was obtained at ~ 970 nm with energy band gap of ~1.16 eV and ~1.19 eV. Silica enhanced the biocompatibility of copper ferrite nanoparticles, thus making them a promising tool for biomedical applications. [ABSTRACT FROM AUTHOR]

Silica scaling is formed by separation process in the geothermal brine transport. Its existence is considered unfavorable because it disturbs efficiency of the geothermal industry. On the other hand, the application of colloidal silica nanoparticles is widely used. As the consequences the natural silica obtained from scaling process are possible to be examined and utilized. One of the practical forms for various application is colloidal silica. In this study the colloidal silica was developed from natural silica formed by geothermal scaling of Dieng power plant, West Java, Indonesia. In colloidal form the colloid stability is very important. It can be improved by the addition of surfactants and by beads milling process to reduce the particle size. The main objective of this study was to determine the most effective type of surfactant to stabilize colloidal silica. By reviewing the zeta potential value of colloids, adding cationic, anionic, and nonionic surfactants, and determined the effect of the milling time on the size distribution of the colloid particles. Determination of overall stability is done by zeta potential and particle size analyzer (PSA). The results showed that the optimum stability was obtained by the addition of 0.1% PEG 6000 nonionic surfactant with a zeta potential -32.7 mV. Through the beads mill method, 134 nm diameter of silica particles suspended in water was observed, obtained through milling for 3 hours and the optimum stability was obtained through milling for 5 hours, with zeta potential -41 mV. [ABSTRACT FROM AUTHOR]

The silica (SiO2) particle was synthesized using the precipitation method of sodium silicate (Na2SiO3) precursor by additional HCl as precipitant. In this paper, the precipitant was mixed directly to the solution of sodium silicate (Na2SiO3) in contrast to the conventional dropwise technique which prevented a high production rate. The dropwise of HCl was carried out to know the effect of pH at two different temperature 25 °C (T20) and 80 °C (T80) on the obtained particles. It was obtained that the optimized process was at temperature 25 C. Subsequently, the mixing technique of HCl (conventional dropwise and direct mixing) were investigated at temperature 25 °C. The result showed that direct mixing technique resulted in high production rate with acceptable size and dispersion of silica nanoparticles. It is also highlighted that the proposed direct mixing technique of HCl received a simple and faster-precipitated process in large scale production. Therefore, it is proposed that for the scale-up production of silica nanoparticle by precipitation of the sodium silicate (Na2SiO3) precursor with additional of HCl may be prepared by direct mixing method at pH 7 in temperature 25°C. [ABSTRACT FROM AUTHOR]

Spodoptera litura is one of the major potato pests that feeds on leaves during the vegetative and generative phases. This pest may cause low quality as well as quantity of potato production. Entomopathogenic fungi can be used to control plant pests. Beauveria bassiana has been reported as pathogenic to many insect pests. However, its effectiveness in controlling S. litura is low. To increase the effectiveness, it can be mixed with plant micro nutrients such as silica, which also protects plants from biotic stress, and a carrier material. Silica Nps. (silica nanoparticles) and carbon fiber as a carrier were used in this study. The experiment was objected to evaluate the effect of application of the mixture of B. bassiana + silica Nps. in various concentrations + carbon fiber on the mortality of S. litura. There were 16 treatments, i.e. the application of single B. bassiana, single carbon fiber, mixture of B. bassiana + carbon fiber, mixture of silica Nps. at 1, 3, and 5% + B. bassiana, mixture of silica Nps. at 1, 3, and 5% + B. bassiana + carbon fiber, mixture of silica Nps. at 1, 3, and 5% + carbon fiber, single silica Nps. at 1, 3, and 5%, and a control. The treatments were applied on the larvae of S. litura by infesting the larvae with the suspension of the S. litura spores. The concentration of the B. bassiana was 108 spores/ml. Mortality of S. litura larvae was assessed up to eighteenth days after application. The results showed that the application of the mixture of B. bassiana + silica Nps. 5% + carbon fiber caused the highest mortality of S. litura larvae (53.33%), compared with 6.67% mortality on the treatment of single B. bassiana. Although, 1% of silica Nps. was adequate. [ABSTRACT FROM AUTHOR]

Geothermal sludge is a waste from geothermal power plants (PLTP) with very high silica content. Geothermal sludge waste is potential as a basic material in the synthesis of silica nanoparticles. The research was conducted using FeCl3 salt as Fe ions precursors forming the silica magnetic nanoparticles. This was obtained by reacting silica waste with NaOH 1,5 N at 90 °C, added with 1,6 gr FeCl3 and subsequently adding 2N HCl solution to form a gel at pH 5 and aging for 18 hours. The calcination temperature of the samples were varied at 400°C, 500°C, 600°C and 700°C. Characterization of magnetic silica nanoparticle included Brauner Emmet Teller (BET) to determine the surface area, X-Ray Diffraction (XRD) for phase identification and morphology of the nanoparticles was characterized Transmition Electron Mycroscope (TEM). The results showed that samples calcined at 400 °C was in its amorphous phase and has the highest surface area of 658.11 m²/g. [ABSTRACT FROM AUTHOR]

Polystyrene/Silica Nanocomposites (PS/Si NCs) are attractive material due to their stability (chemical and thermal), low toxicity, the probability from controlling their particle size, ability to be functionalized with a range of molecules and polymers, biocompatibility, degradability below physiographic statuses and low-cost production of materials. In that paper now, The procedure to fabricate polystyrene/silica (PS/SiO2) hybrid hollow spheres did successfully combine by precipitation technique, which was then used to react with silica nanoparticles that were prepared by the sol-gel method to fabricate PS/SiO2 nanocomposite. Four Point Probe, Transition electron microscopy (TEM), and XRD are used to analyze the physical, chemical, optical properties and electric of polystyrene/SiO2 nanocomposites. The experimental effects indicate the possibilities for PS/SiO2 to be used as biomaterials, coating and catalyst materials. [ABSTRACT FROM AUTHOR]

Hollow core-shell silica nanoparticles (HCSNs) with desirable interior space have attracted intensive interest in the field of controlled drug delivery. In the present research work facile two-step method was employed to synthesize HCSNs by using sacrificial polystyrene (PS) template. Monodispersed spherical polystyrene nanoparticles with size range 200-250 nm were synthesized by emulsion polymerization method. Silica was coated on PS template using TEOS as precursor and cetyltrimethyl ammonium bromide (CTAB) as the shell structure directing agent. Complete removal of the template particles was achieved by calcination at 550 °C confirmed by fourier transform infrared spectroscopy (FTIR). Variation in pore size was attained by altering ethanol/water volume ratio and visualized in scanning electron microscope (SEM). Average specific surface area of HCSNs verified by Brunauer Emmett Teller (BET) method observed to be 842.57 m²/g. Drug release behavior was investigated using doxorubicin as model drug by varying pore size of HCSNs, displayed a pore size dependent release. HCSNs with reduced pore size (2.2 nm) showed maximum delay in the doxorubicin release, demonstrated the potential application of HCSNs in targeted drug delivery. [ABSTRACT FROM AUTHOR]

In this research, six different types of rice husk ash (RHA) were developed through various synthesis methods, in order to obtain a high concentration of silica for future applications in zeolite synthesis processes as a silicon base. The as-synthesized samples were characterized by X-ray fluorescence (XRF) to calculate the elemental composition, by scanning electron microscopy (SEM) to observe the microstructure and the particle size, and by laser granulometry to determine particle size distribution. Based on these analyses, it was verified which of the obtained RHA samples present higher silica concentration and the optimal microstructure, in order to capitalize them in the proposed applications. For all RHA samples, silica concentration exceeded 85%, although, the approached synthesis routes had a high influence on the physico-chemical characteristics of the resulting powders. [ABSTRACT FROM AUTHOR]

Concentration gradient of colloidal dispersion during drying of its solvent in a porous substrate has been probed by small-angle X-ray scattering (SAXS). Silica nanoparticles of two different sizes have been considered to study its deposition behavior in a cellulose sheet. After completion of solvent drying, the fibrous sheet has been line scanned by SAXS at different positions with a step size of 0.5 mm along a horizontal line. The spread of the colloids i.e. its concentration gradient has been found to be strongly dependent on colloidal size. The dried pattern of such colloids forms fractal network in the porous sheet. [ABSTRACT FROM AUTHOR]

Cement based silicate materials, utilized in the radioactive waste disposal system, may attain high pH value after contact with groundwater. The dissolution of the silicates under high alkaline environment may compromise the integrity of the immobilized radioactive waste. Thus, understanding of dissolution kinetics of amorphous silica at high pH condition is very crucial. Small-angle X-ray scattering (SAXS) is a non destructive method that can provide quantitative structural information in mesoscopic length scale. Here, we report real time SAXS investigation on the structural modification of silica nanoparticles during the dissolution reaction of silica with NaOH at pH value of ∼12. The scattering intensity due to silica nanoparticles reduces with increase in reaction time owing to the decrease in the size of the particles because of dissolution reaction. The temporal dependence of particle size and the fraction dissolved have been revealed. Signature of existence of silica in the form of nanoparticles was found to be ceased beyond one hour. [ABSTRACT FROM AUTHOR]

Mesoporous silica nanoparticles (MSN) offer so many advantages as drug carrier, including large surface area, controllable pore size and morphology, and ease surface modification. Chitosan modified MSN has been synthesized to obtain drug carrier with pH dependent properties. Chitosan itself has been used in many studies as drug carrier due to its biocompatibility. In the present study, we combined MSN and chitosan in order to take advantage the high surface area and pore volume of MSN, and also the specific characteristics of chitosan at different pH values. The modification enables optimization of drug release at a low pH. The chitosan attachment on the surface of MSN was characterized by using FTIR. The release study of chitosan modified MSN at a variety of pH showed that the modification creates a controlled release profile of drug molecule (curcumin). At a high pH value, the accumulation release was low compared to that at a low level of pH. The release profile of chitosan-modified MSN at different concentrations of chitosan was also studied. The chitosan-MSN showed a controlled release profile. [ABSTRACT FROM AUTHOR]

This experiment study the effect of nanoparticles blended in biodiesel on combustion characteristic of single-cylinder four-stroke diesel engine. Biodiesel used in this experiment was palm oil methyl ester (POME) and nanoparticles used was aluminum oxide (Al2O3) and silicon dioxide (SiO2). Both nanoparticles was dispersed in POME by using an ultrasonicator with the dosage of 50 ppm. The fuel was labelled as PS50 for POME + SiO2 fuel blend and PA50 for POME+Al2O3 fuel blend. These fuel was tested with a YANMAR TF120M model diesel engine with load variation from zero engine load until 28 N.m engine load with constant engine speed at 1500 rpm. Results shows that peak pressure of PS50 fuel was higher than PA50 fuel at all engine loads operations and the significant difference was at zero load engine operations, where the difference was 2.89%. In addition, exhaust gas temperature of PS50 blend recorded also shows that it was lower than PA50 blend at all engine load operations by 2.71 %, 2.42 %, 3.47 %, 5.65 % and 4.12 %. [ABSTRACT FROM AUTHOR]

The paper considers the elastic properties of epoxy composites reinforced by 6 types of silica nanoparticles with different average diameter at the same weight concentration of 1.1%. The addition of silicon nanopowders increases the modulus of elasticity. For powders of the same origin, with an increase of the modulus of elasticity, a decrease in the characteristic diameter of the filler particles at a constant concentration is observed. It is shown that the characteristic average particle size is not the only factor determining the growth of the elastic modulus, since the growth of the modulus is significantly different for powders of different producers. [ABSTRACT FROM AUTHOR]

Silica geothermal is abundantly available as side products or waste from the production of energy from Geothermal Power Plants. These inexpensive waste materials was used to produce silica nanoparticles which in return increased the value of silica geothermal. The purpose of this research is to synthesize nanoparticle silica from geothermal waste following the sol-gel method. This was conducted by reacting silica waste with NaOH 1.5 N and subsequently the addition of 2N HCl solution to form a gel at pH 5. The ageing time of the gel were varied from 18 to 72 hours and the specific surface area were characterized by the Brauner Emmett Teller (BET) Adsorption. Aging time at 18 hours showed the highest specific surface area of 289 m²/g. The surface chemistry of the silica nanoparticles were performed using Fourier Transform Infra Red (FTIR) which showed that silanol dan siloxane groups were prominent. In contrast with its precursor, the silica geothermal waste, which was in its amorphous phase, the X-Ray Diffraction (XRD) of the silica nanoparticles showed high crystallinity. [ABSTRACT FROM AUTHOR]

In this research, the means of image processing techniques are utilized to calculate the effective average surface porosity size for to zirconium samples that enforced by nano-silica with two different additive rate (80% and 60%), the surface cross-section of the two samples acquired with SEM scanner machine. Different pre-processing image enhancement techniques (median, thresholding and morphological operator) are used to prepare the image in order to calculate the porous size. The calculated average effective porous size decreased with the nano-silica rate. [ABSTRACT FROM AUTHOR]

This paper aims to investigate the influence of replacement of cement with nano silica, micro silica and silica gel admixtures on pozzolanic activity, the replacement ratio waslO% for all admixture, silica gel used in two forms (beads and crushed powder). Also, the water absorption test was investigated for obtaining the durability properties of concrete, in specimens for this test admixtures were added in four different dosages 1%, 2%, 3% and 4% by weight of the cementitious material into the concrete mixture. Experimental investigations of modified concrete were conducted after 28 days of water curing. Results showed that mixes of nano silica and crushed silica gel showed a higher pozzolanic activity index. For the water absorption test, all mixes incorporating nano silica, micro silica and silica gel showed lower absorption than control mixes best result were noticed with crushed silica gel and nano silica mixes. DTA analysis confirms the results for both poisonous activity and water absorption. [ABSTRACT FROM AUTHOR]

Nano-silica (SiO2) with a different additive of zirconia to form a composite material has a thickness of 1.5mm for all obtained specimens. The effect of nano-silica with different additive rates on the dielectric strength, voltage rise rate and number of voltage breakdown period is studied. Results showed that 80% nano-silica additive rate is the most effected rate on the properties of the ceramic-ceramic composite material (zirconia-nano-silica composite). [ABSTRACT FROM AUTHOR]

Sodium alginate/gelatin hydrogels are promising materials for 3D bio-printing due to its good biocompatibility and biodegradability. Gelatin is used for thermal crosslinking and its cell adhesion properties. Hence patient specific sodium alginate/gelatin hydrogel scaffolds can be bio-fabricated in a temperature range of 4-14 oC. In this study we made an attempt to introduce silica (SiO2) nanoparticles in the polymer network of sodium alginate (2.5%)/gelatin (8%) hydrogel at different concentrations (w/v) as 0%, 1.25%, 2.5%, 5%, and 7.5%. The effect of silica nanoparticles on viscosity, swelling behavior, and degradation rate are analyzed. Hydrogels with 5% silica nanoparticles show significantly less swelling and degradation when compared to other concentrations. The viscosity of the hydrogels gradually increases up to 5% addition of silica nanoparticles enhancing the stability of 3D printed structures. [ABSTRACT FROM AUTHOR]

We present the studies on the structural properties of monolayer Bidisperse silica (SiO2) nanoparticles (BDS) on Silicon (Si-100) substrate using spin coating technique. The Bidisperse silica nanoparticle was synthesised by the modified sol-gel process. Nanoparticles on the substrate are generally assembled in non-close/close-packed monolayer (CPM) form. The CPM form is obtained by depositing the colloidal suspension onto the silicon substrate using complex techniques. Here we report an effective method for forming a monolayer of bidisperse silica nanoparticle by three step spin coating technique. The samples were prepared by mixing the monodisperse solutions of different particles size 40 and 100 nm diameters. The bidisperse silica nanoparticles were self-assembled on the silicon substrate forming a close-packed monolayer film. The scanning electron microscope images of bidisperse films provided in-depth film structure of the film. The maximum surface coverage obtained was around 70-80%. [ABSTRACT FROM AUTHOR]

We report on self-assembled nanodisc formations of silica nanoparticles on a surface modified silicon substrate using modified Langmuir-Schafer deposition technique (stamping). The size, inter-particle separation as well as the packing of the silica nanoparticles within the nanodiscs formed spontaneously can be tuned by the surface pressure applied on the water surface. We obtain self-assembled nanodiscs of silica nanoparticle arranged in a hexagonal symmetry. We also observe that by varying the surface pressure of deposition at the water-molecule-air interface we obtain such 2D disc-shaped structure with varying sizes and a packing ratio of the silica nanoparticle. [ABSTRACT FROM AUTHOR]

The advancement of nanoparticle-based approaches such as quantum dots (QDs), metallic (Au and Ag) NPs, silica NPs and other types of nanomaterial have led to a large variety of biomolecular imaging and labelling reagents with controlled size and shaped to overcome the limitation of conventional organic dye. In this study, the yellowish green color of fluorescein dye was encapsulated into colloidal silica nanoparticles by using micelle entrapment approach. Two different size of silica nanoparticles encapsulated fluorescein dye (27.7 ± 5.6 and 46.73 ± 4.3 nm) with spherical and monodispered of nanoparticles were synthesised by varying the volume of co-solvent during the synthesis process. The particles size, particles morphology, absorption spectrum and the photostability of fluorescein dye was measured by using dynamic light scaterring (DLS), Transmission Electron Microscope (TEM) and UV-Vis spectrometer. Furthermore, the effect of photostability of of silica nanoparticles encapsulated fluorescein dye was measured under radiation of 200 W of Halogen lamp for 60 minutes. The silica nanoparticles encapsulated fluorescein dye was more stable compared to bare fluorescein dye after the exposure. In conclusion, the photostability of silica nanoparticles encapsulated fluorescein dye was improved compared to bare fluorescein dye, thus silica nanoparticles encapsulation successfully provides protection from the photobleaching and photodegradation of fluorescein dye. [ABSTRACT FROM AUTHOR]

Despite the increasing applications of nanoparticles in enhanced oil recovery (EOR), there is not enough information about the mechanisms and microscopic aspects of nanoparticles' effects. Therefore, in this research, molecular dynamics simulation is used to provide the molecular-scale insight for investigation of the silica nanoparticles effects on the oil adsorption on calcite surface for the first time. The surface interacts with the mixture of heptane and decane as the oil phase with mole ratio of 1/2 and silica nanoparticles are dispersed in distilled water with concentration of 7000 ppm. Based on the simulation results, by using nanoparticles surface adsorption behavior have been changed to hydrophilic and the oil molecules departed from the calcite. This result is based on the oil-calcite binding energy calculation which is decreased from 5224 kcal/mol to 3278 kcal/mol by using silica nanoparticles. In addition, calculation of radial distribution functions showed that after adding silica nanoparticles, the picks fall which means increasing in average distance between oil and calcite surface. [ABSTRACT FROM AUTHOR]

Sulfur functionalized silica nanocapsules (S-SiNC) was successfully synthesized and characterized as a potential adsorbent for industrial applications. The synthesis of S-SiNC was carried out using the mircoemulsion templating method using cetyltrimethylammonium bromide (CTAB) as cationic surfactant, toluene as co-solvent, ammonia solution as catalyst, and tetraethylorthosilicate (TEOS) as the silica base. The S-SiNC adsorbent was characterized using Transmission Electron Microscope, Fourier Transformed Infra Red spectroscopy and nitrogen adsorption/desorption analysis. The physical and chemical properties of the SiNC changed as a result of the functionalization, hence affecting the extent of Hg(II) adsorption. The S-SiNCs were also tested in mercury ion [Hg(II)] adsorption via batch adsorption process with variation in initial Hg (II) concentration. It was found that there is a significant improvement in Hg(II) adsorption performance after being functionalized with elemental sulfur. The highest Hg(II) adsorption capacity was obtained for SSiNC (107.875 mg/g), which significantly outperformed the blank SiNC. The experimental data obtained was found to be fitting well to the Langmuir isotherm model (R²= 0.979) compared to Freundlich isotherm model. Thus, the results demonstrated the potential application of sulfur functionalized silica nanocapsules as adsorbent in industrial applications. [ABSTRACT FROM AUTHOR]

Fluorescence dyes are based on small organic molecules have become of interest in chemical biology and widely used for cell and intracellular imaging. However, fluorescence dyes have limitations such as photo bleaching, poor photochemical stability and has a short Stokes shift. It is less valuable for long-term cell tracking strategies and has very short lifetime. In order to overcome the problems, dye-incorporated nanomaterials become of interest. Nanomaterials encapsulation provides a protection layer around the fluorescence dye which improves the stability of fluorescence dye. In this study, silica nanoparticles encapsulated with 1,1%-dioctadecyl-3,3,3%,3%-tetramethylindocarbocyanine perchlorate (Dil) was successfully synthesised by using micelle entrapment method to investigate the effect of encapsulation of nanoparticles towards the properties of fluorescent dye. The synthesised nanoparticles (SiDil) was characterised by particle size analyser, Transmission Electron Microscopy (TEM), UV-Vis spectrometer and Fluorescent spectrometer. Observation using TEM showed spherical shape of nanoparticles with 53 nm diameter. Monodispersed and well nanoparticles distribution was confirmed by low polydispersity index of 0.063 obtained by particle size analyser. Furthermore, the photoluminescence properties of the SiDil were evaluated and compared with bare Dil dye. Both SiDil and bare Dil was radiated under 200 W of Halogen lamp for 60 minutes and the absorbance intensity was measured using UV-Vis spectrometer. The result showed more stable absorbance intensity for SiDil compared to bare Dil dye, which indicated that Si nanoparticles encapsulation improved the photostability property. [ABSTRACT FROM AUTHOR]

The experimental and numerical investigations of synthesis of silica (SiO2) nanoparticles from premixed gaseous silicon tetrachloride (SiCl4) and oxygen of dry air in the high-temperature nitrogen flow of plasma-chemical reactor have been carried out. The regime of counter flow jet quenching of high-temperature heterogeneous flow has been utilized. The latter provided a rapid cooling of silica particles under nonequilibrium conditions with substantial temperature gradients. Synthesized silica particles were amorphous, with surface-average size being about 28 nm. The results of numerical calculations are found to agree qualitatively with experimental data. [ABSTRACT FROM AUTHOR]

Membrane technology has long been applied for waste water treatment industries due to its numerous advantages compared to other conventional processes. However, the biggest challenge in pressure driven membrane process is membrane fouling. Fouling decreases the productivity and efficiency of the filtration, reduces the lifespan of the membrane and reduces the overall efficiency of water treatment processes. In this study, a novel membrane material is developed for water filtration. The developed membrane incorporates silica nanoparticles mainly to improve its structural properties. Membranes with different loadings of silica nanoparticles were applied in this study. The result shows an increase in clean water permeability and filterability of the membrane for treating activated sludge, microalgae solution, secondary effluent and raw sewage as feed. Adding silica into the membrane matrix does not significantly alter contact angle and membrane pore size. We believe that silica acts as an effective pore forming agent that increases the number of pores without significantly altering the pore sizes. A higher number of small pores on the surface of the membrane could reduce membrane fouling because of a low specific loading imposed to individual pores. [ABSTRACT FROM AUTHOR]

Silica nanoparticles have been great attention as it being evaluated for used in abundant fields and applications. Due to this significance, this research was conducted to synthesis silica nanoparticles using local agricultural waste, sugarcane bagasse. We executed extraction and precipitation process as it involved low cost, less toxic and low energy process compared to other methods. The Infrared (IR) spectra showed the vibration peak of Si-O-Si, which clearly be the evidence for the silica characteristics in the sample. In this research, amorphous silica nanoparticles with spherical morphology with an average size of 30 nm and specific surface area of 111 m2/g-1 have been successfully synthesized. The XRD patterns showed the amorphous nature of silica nanoparticles. As a comparison, the produced silica nanoparticles from sugarcane bagasse are compared with the respective nanoparticles synthesized using Stöber method. [ABSTRACT FROM AUTHOR]

Colloidal crystals are closely related to photonic crystals as both of them can be considered as composite materials with a spatial distribution of building blocks. The first step in fabricating such a crystal is the development of highly monodisperse spherical nanomaterials. In this work silica nanoparticles with fine spherical shapes were prepared by following a seeded growth method. The effect of different fabrication conditions on the shape and monodispersity of the prepared spheres were analyzed with the help of scanning electron microscopy and dynamic light scattering systems. The use of the prepared sample for colloidal crystal growth is analyzed using UV-Vis spectra. [ABSTRACT FROM AUTHOR]

Rheological properties are influenced by many factors ranging from the characteristics of the carrier fluid (poly(vinyl butyral)), solvent (methanol) and a filler (fumed silica nanoparticles) to the flowing conditions. There is compared rheological characterization of the neat PVB solution with the PVB/silica suspension. This characterization is confronted with quality of the corresponding nanofibrous mats and a role of elasticity is discussed. It is shown that in this case a role of elasticity is rather limited. [ABSTRACT FROM AUTHOR]