Effect Of Al2O3 Nanoparticles Research Articles

Toxic Kidney Damage in Rats Following Subchronic Intraperitoneal Exposure to Element Oxide Nanoparticles.

Chronic diseases of the urogenital tract, such as bladder cancer, prostate cancer, reproductive disorders, and nephropathies, can develop under the effects of chemical hazards in the working environment. In this respect, nanosized particles generated as by-products in many industrial processes seem to be particularly dangerous to organs such as the testes and the kidneys. Nephrotoxicity of element oxide particles has been studied in animal experiments with repeated intraperitoneal injections of Al2O3, TiO2, SiO2, PbO, CdO, CuO, and SeO nanoparticles (NPs) in total doses ranging from 4.5 to 45 mg/kg body weight of rats. NPs were synthesized by laser ablation. After cessation of exposure, we measured kidney weight and analyzed selected biochemical parameters in blood and urine, characterizing the state of the excretory system. We also examined histological sections of kidneys and estimated proportions of different cells in imprint smears of this organ. All element oxide NPs under investigation demonstrated a nephrotoxic effect following subchronic exposure. Following the exposure to SeO and SiO2 NPs, we observed a decrease in serum creatinine and urea, respectively. Exposure to Al2O3 NPs caused an increase in urinary creatinine and urea, while changes in total protein were controversial, as it increased under the effect of Al2O3 NPs and was reduced after exposure to CuO NPs. Histomorphological changes in kidneys are associated with desquamation of the epithelium (following the exposure to all NPs except those of Al2O3 and SiO2) and loss of the brush border (following the exposure to all NPs, except those of Al2O3, TiO2, and SiO2). The cytomorphological evaluation showed greater destruction of proximal sections of renal tubules. Compared to the controls, we observed statistically significant alterations in 42.1% (8 of 19) of parameters following the exposure to PbO, CuO, and SeO NPs in 21.1% (4 of 19)-following that, to CdO and Al2O3 NPs-and in 15.8% (3 of 19) and 10.5% (2 of 19) of indicators, following the exposure to TiO2 and SiO2 nanoparticles, respectively. Histomorphological changes in kidneys are associated with desquamation of epithelium and loss of the brush border. The cytomorphological evaluation showed greater destruction of proximal sections of renal tubules. The severity of cyto- and histological structural changes in kidneys depends on the chemical nature of NPs. These alterations are not always consistent with biochemical ones, thus impeding early clinical diagnosis of renal damage. Unambiguous ranking of the NPs examined by the degree of their nephrotoxicity is difficult. Additional studies are necessary to establish key indicators of the nephrotoxic effect, which can facilitate early diagnosis of occupational and nonoccupational nephropathies.

Effect of Al2O3 Nanoparticles in the Antiwear Properties of a Base Vegetal Lubricant.

Effect of Al2O3 Nanoparticles in the Antiwear Properties of a Base Vegetal Lubricant.

Inhibition of asphaltene deposition by Al2O3 nanoparticles during CO2 injection

Carbon dioxide flooding is of interest due to its high oil-sweep efficiency for enhanced oil recovery and contribution to the reduction of greenhouse gas emissions. However, when CO2 is injected into deep geological strata, asphaltene may precipitate. In this work, the effect of Al2O3 nanoparticles on the deposition of asphaltene was examined by assessing the variations of bond number and interfacial tension at different pressures and a temperature of 60 °C. The asphaltene onset point and intensity were characterized using the bond number, which proved a better indicator of changes in oil droplet shape and interfacial tension with gravity. Synthesized mixtures of toluene and n-heptane that contained two different kinds of asphaltenes were used as M and D oil samples. A 0.06 mass% addition of Al2O3 nanoparticles, which worked best for reduction of interfacial tension, was also applied at various pressures. Addition of nanoparticles to the oils prevented asphaltene precipitation in both synthetic samples by altering the slope of the plot of interfacial tension with pressure by 49.7% for the M sample and 9.0% for the D sample. The Al2O3 nanoparticles were found to be more effective at inhibiting asphaltene precipitation for the M oil sample due to its lower H/C ratio and higher nitrogen content.

Effect of Al2O3 Nanoparticles on the Compression Ignition Performances and Emitted Pollutants of a Diesel Engine

Effect of Al2O3 Nanoparticles on the Compression Ignition Performances and Emitted Pollutants of a Diesel Engine

Effect of Al2O3 Nanoparticles on Performance and Emission Characteristics of Diesel Engine Fuelled with Diesel–Neem Biodiesel Blends

Indagation in the sphere of nanoparticle utilisation has provided commendatory upshots in discrete areas of application varying from medicinal use to environmental degradation alleviation. This study incorporates alumina nanoparticles as additives to diesel and biodiesel blends. The prime objective of the present study was the scrutinisation of the denouement of Al2O3 nanoparticle incorporation in diesel–biodiesel blends on a diesel engine’s performance and emission characteristics. Test fuel samples were prepared by blending different proportions of biodiesel and dispersing two concentrations of alumina nanoparticles (25 and 50 ppm) in the diesel. Dispersion was made without the use of a nanoparticle stabiliser to meet real-world feasibility. High-speed shearing was employed to blend the biodiesel and diesel, while nanoparticles were dispersed in the blends by ultrasonication. The blends so devised were tested using a single-cylinder diesel engine at fixed RPM and applied load for three compression ratios. Upshots of brake-specific fuel consumption (BSFC) and brake thermal efficiency (BTE) for fuel samples were measured with LabView-based software, whereas CO emissions and unburnt hydrocarbon (UBHC) emissions were computed using an external gas analyser attached to the exhaust vent of the engine. Investigation revealed that the inclusion of Al2O3 nanoparticles culminates in the amelioration of engine performance along with the alleviation of deleterious exhaust from engine. Furthermore, the incorporation of alumina nanoparticles assisted in the amelioration of dwindled performance attributed to biodiesel blending. More favourable results of nanoparticle inclusion were obtained at higher compression ratios compared to lower ones. Reckoning evinced that the Al2O3 nanoparticle is a lucrative introduction for fuels to boost the performance and dwindle the deleterious exhaust of diesel engines.

Synthesis and Characterization UV-Curable Waterborne Polyurethane Acrylate/Al2O3 Nanocomposite Coatings Derived from Jatropha Oil Polyol

A new UV-curable waterborne polyurethane acrylate/alumina (UV-WPUA/Al2O3) coatings were successfully developed. The waterborne polyurethane acrylate (WPUA) dispersion was synthesized by reacting jatropha oil polyol (JOL) with isophorone diisocyanate (IPDI), 2,2-dimethylol propionic acid (DMPA), and 2-hydroxyethyl methacrylate (HEMA) via in-situ and anionic self-emulsifying methods. The WPUA/Al2O3 dispersion was formulated by various sonicating concentrations of alumina nanoparticles (0.3, 0.6, 0.9, and 1.2 wt%) into WPUA dispersion. The UV-WPUA/Al2O3 coatings were obtained with 75 wt% oligomers, 25 wt% monomer trimethylolpropane triacrylate (TMPTA), and 3 wt% of a commercial photoinitiator (benzhophenol) for UV-curing were used. The effect of Al2O3 nanoparticles on WPUA coatings was analyzed by FTIR, surface morphology, and coating performance properties such as pendulum hardness, pencil hardness, scratch resistance, and adhesion test. FTIR revealed the formation of JOL, neat UV-WPUA, and UV-WPUA/Al2O3 coatings, respectively. FESEM/EDX demonstrated that Al2O3 nanoparticles at the lower loading (up to 0.6 wt%) were well-dispersed correlated with contact angle (CA). The hardness property can reach 63.4% at the lower concentration of the Al2O3 addition 0.6 wt%. The adhesive strength, scratch hardness, and scratch resistance were greatly improved to 5B, 5H, and 2N, respectively. The preparation method offered in this study is an effective and convenient approach to producing UV-WPUA/Al2O3 coatings. The enhancement of the properties with the lesser concentration of Al2O3 nanoparticles (≤ 0.6 wt%) addition in this study shows a new promising potential as surface coating application for several major industrial areas, such as marine, transportation, and biomedical field with major economic and environmental benefits.

Effect of Al2O3 Nanoparticles as Reinforcement on the Wear Properties of A356/Al2O3 Nanocomposites Produced by Powder Metallurgy

Abstract In this study, microstructure and wear properties of A356 aluminum matrix nanocomposites reinforced with nano-Al2O3 particles were investigated. The powder metallurgy method was used for the production of 1 wt% and 2 wt% nano-Al2O3 particle reinforced nanocomposites. After 1 h of mechanical milling of A356 and nano-Al2O3 powders, green compacts were obtained by cold pressing. Green compacts were sintered at 550 °C in a vacuum environment (10−6 mbar) for 1 h. Samples were characterized by density, hardness measurements, scanning electron microscopy investigations, and wear tests. As the reinforcement ratio increased, there was a decrease in the densities of the nanocomposites, as well as an increase in the porosity. The highest hardness and the lowest weight loss values were obtained in 1 wt% Al2O3 reinforced nanocomposites. A decrease in hardness was measured at 2 wt% Al2O3 reinforced nanocomposites.

Effect of Al2O3 nano-particles on Ba(Zr0.95Ti0.05)O3 ceramics prepared by mixed oxide method

In this study, the effect of Al2O3 nano-particles on Ba(Zr0.95Ti0.05)O3 or BZT ceramics prepared by mixed oxide method with various amount of Al2O3 were investigated. The BZT powders were calcined at 1100 °C for 3 h with heating rate of 5 °C/min. The sintering procedure of BZT + x wt.% Al2O3 nano-particles (x = 0.3, 0.7 and 1.0) was carried out at 1300 °C for 2 h with heating rate of 5 °C/min. The results showed that, all XRD patterns of BZT + x wt.% Al2O3 nano-particles ceramics could be matched with a JCPDS data file number 06-0399. The BZT + 0.7 wt.% Al2O3 nano-particles ceramic was showed the highest density about 5.9 g/cm3, Vickers micro-hardness was 8.9 GPa, dielectric constant was 2005 and dielectric loss was 0.01 at 1 kHz frequency.

Effect of Al2O3 Nanoparticles and Heat Treatment on the Wear Resistance of Electrodeposited Ni-W/Al2O3 Composite Coatings

Effect of Al2O3 Nanoparticles and Heat Treatment on the Wear Resistance of Electrodeposited Ni-W/Al2O3 Composite Coatings

The Electro-optical study of Al2O3 nanoparticles doped polymer dispersed liquid crystal films

ABSTRACT The electro-optical characteristics of nanoparticles-doped polymer dispersed liquid crystals (PDLCs) have been investigated for display applications. The PDLC samples were obtained by polymerisation induced phase separation of the nematic liquid crystal LC-nanoparticles-prepolymer mixtures under UV illumination with a constant intensity. The effect of Al2O3 nanoparticles doping on the PDLC system was studied. It was seen that the electro-optical characteristics of PDLC were dependent on the amount of Al2O3 nanoparticles used. The effect of morphology on the electro-optical properties was examined, and the experimental results indicated that the driving voltage was affected considerably by the amount of Al2O3 nanoparticles. The results showed that the nanoparticles concentration can be optimised to obtain promising electronic materials with a minimum threshold for display applications.

Effect of Al2O3 nanoparticles on the corrosion behavior of aluminum alloy in simulated vehicle coolant

The use of nanofluids as vehicle coolant can significantly improve the heat exchange efficiency, but it is necessary to understand its corrosiveness to metals before use. Corrosion behavior of aluminum alloy in simulated vehicle coolant (SVC), nano Al2O3 coolant (SVC-Al2O3), simulated coolant containing sodium dodecyl benzene sulfonate (SVC-SDBS) and nano Al2O3 coolant containing SDBS (SVC-Al2O3-SDBS) was investigated by electrochemical impedance spectroscopy, polarization curve, weight loss analysis and surface analysis in this paper. The results showed that in the three media of SVC, SVC-SDBS and SVC-Al2O3-SDBS, the impedance modulus at the frequency of 10 mHz |Z|0.01, the charge transfer resistance Rct and the film resistance Rf of aluminum alloy electrode increased with the immersion time. Compared with the three media, the aluminum alloy in SVC-Al2O3 medium had the lowest |Z|0.01, Rct and Rf, and had the highest corrosion current density, implying that Al2O3 nanoparticles promoted the corrosion of aluminum alloy in SVC, and the corrosion products formed on the alloy surface were Al2O3, Al(OH)3, AlOOH, which were loose and not protective. The Rf values of aluminum alloy electrode increased significantly with time in the media containing SDBS. The aluminum alloy exhibited the best corrosion resistance in the medium of SVC-SDBS and no obvious loose corrosion products but compact passivation film could be seen on the alloy surface. SDBS exhibited a good corrosion inhibition effect on aluminum alloy, which may be due to the adsorption of SDBS on the metal surface and the fact that SDBS promoted the formation of the passive film by preventing the transformation of alumina film to loose AlOOH layer. In the medium containing both SDBS and Al2O3 nanoparticles, the corrosion inhibition effect of SDBS was weakened. This maybe due to the electrostatic attraction of positively charged Al2O3 nanoparticles and negatively charged SDBS, which reduced the adsorption of SDBS on the metal surface, thereby weakening the protective effect of SDBS on the metal surface.

The Effect of Al2O3 Nano Particles on Characteristics of Mg-Al-5TiB Grain Refiner Composites Produced by Stir Casting Method

High needs for light material with good mechanical characteristics made magnesium and its alloys as an alternative choice because of magnesium’s low density, 1.74 gr/cm3. However, its use is limited by its low strength and ductility. In this experiment, a fabrication process of the composite which is Mg-Al-5TiB as Matrix with the addition of Nano Al2O3 as a reinforced with volume fraction varied from 0.10 Vf-% to 0.25 Vf-% by stir casting method. The composites then were characterized by both microstructure and mechanical properties. The microstructure was analyzed by an optical microscope and scanning electron microscope link to energy-dispersive spectra to analyze the phases present in composites and confirmed by X-Ray Diffraction. The XRD shows some phases such as Mg, MgO, MgAl2O4, and B2O3. The optimum mechanical properties of composites were obtained at the addition of 0.2 Vf-% Al2O3, where the tensile strength, elongation, wear rate and impact strength were 46.1 MPa, 14%, 0.3x10-5 mm3/s, and 0.06 J/mm2. The hardness of composites was value, 40.1 HRH. The porosity maximum was found at the addition of 0.25 Vf-% with the value of 9.37% caused by nano Al2O3 particle forming clustering (porosity is related to clustered particles) and inhibiting liquid metal moving rate. The addition of grain refiner makes solidification went faster and refined the grains.

Simultaneous reduction of emissions as well as fuel consumption in CI engine using water and nanoparticles in Diesel - Biodiesel blend

ABSTRACT Stringent emission norms along with the drastic change in climate lead the direction of research in enhancing the engine combustion to decrease the consumption of fuel and also emissions. Blending fuel with additives leads to improve fuel activity, which helps to overcome these challenges. In present work, the combined effect water and aluminum oxide nanoparticles as a fuel blend was considered. The blended fuel tested on a single cylinder, four-stroke diesel engines. The (compression ignition) CI engine was tested for its performance, emission and combustion characteristics. The results showed that B10W8N100 showed better brake thermal efficiency than B10W8 and B10, i.e., 7.6% and 10.72% increase, respectively. Carbon monoxide (CO) was decreased by 13.5% and 24.4% compared to B10W8 and B10, respectively. The catalytic effect of Al2O3 nanoparticles leads to improved combustion. The addition of nanoparticles in the fuel decreased the Nitric oxide (NO) emissions. It was less compared to conventional fuel by 50%.

Vpliv dodajanja Al2O3 nanodelcev na tribološke lastnosti nerjavnega jekla

Vpliv dodajanja Al2O3 nanodelcev na tribološke lastnosti nerjavnega jekla

EFFECT OF AL2O3 NANOPARTICLES ON CORROSION BEHAVIOR OF ALUIMNUM ALLOY (AL-4.5 WT% CU-1.5 WT% MG) FABRICATED BY POWDER METALLURGY

In this research the effect of Al2O3 nanoparticles on corrosion behavior of aluminum base alloy (Al-4.5 wt% Cu-1.5 wt% Mg) has been investigated. Nanocomopsites reinforced with variable contents of 1, 3 and 5 wt% of Al2O3 nanoparticles were fabricated using powder metallurgy. All samples were prepared from the base alloy powders under the best powder metallurgy processing conditions of 6 hr of mixing time, 450 MPa of compaction pressure and 560 °C of sintering temperature. Density and micro hardness measurements, and electrochemical corrosion tests are performed for all prepared samples in 3.5 wt% NaCl solution at room temperature using potentiostate instrument. It has been found that density and micro hardness of the nanocomposite increase with increasing of wt% Al2O3 nanoparticles to Al matrix. It was found from Tafel extrapolation method that corrosion rates of the nanocomposites reinforced with alumina nanoparticles were lower than that of base alloy. From results of corrosion test by potentiodynamic cyclic polarization method, it was found the pitting corrosion resistance improves with adding of Al2O3 nanoparticles. It was noticed that the pits disappear and the hysteresis loop disappears also from anodic polarization curve.

Adjustment of morphological and dielectric properties of ZnTiO3 nanocrystalline using Al2O3 nanoparticles

The effect of Al2O3 nanoparticles on the crystalline phase, morphology and adjustment of dielectric properties of ZnTiO3 nano-powder has been investigated. The structural and morphological properties were investigated by X-ray diffraction (XRD), field emission-scanning electron microscope (FE-SEM) and Fourier Transform infra-red (FTIR) spectroscopy. The average particle size of the rhombohedral perovskite structure ZnTiO3 and Al2O3/ZnTiO3 is about 61 nm and 53 nm, respectively. Introduction of Al2O3 NPs induces structural and morphological modifications, causes an adjustment in pore structure and textural characteristics of ZnTiO3 nano-powder. In addition, the dielectric results have appeared that the dielectric constant and dielectric loss, [tan(δ)] are decreased with introducing the Al2O3 NPs in the crystalline nano-sized ZnTiO3 powders. The gained results are presented in detail.

Effect of Al2O3 nanoparticles on laminar, transient and turbulent flow of isopropyl alcohol

The laminar, transient and turbulent heat transfer and hydrodynamic of a new nanofluid isopropanol/Al2O3 is investigated in a closed flow loop with a horizontal mini-channel test section (3.5 mm inner diameter) under uniform heat flux conditions. The experiments performed at various inlet temperatures (15, 25, 35 °C), mass flow rates (from 0.00076 to 0.041 kg/s) and nanoparticle concentrations (0.387, 0.992, 3.12, 4.71 mass%). We found that despite the pressure drop increases with Reynolds number and nanoparticles mass fraction the dependence of friction factor for the isopropanol/Al2O3 nanofluid remains the same as for the base fluid. The heat transfer performance of isopropanol/Al2O3 nanofluid was evaluated in two ways (i) depending on the Reynolds number and (ii) product of the mass flow rate and specific heat capacity. The first approach indicates to significant enhancement of the heat transfer coefficient with addition of nanoparticles in all range of experimental parameters. The second approach shows no effect of nanoparticles on the heat transfer coefficient in laminar flow and its deterioration in transient and turbulent flows. Both effects of nanoparticles on the heat transfer are attributed to change in intensity of the turbulence in nanofluids compared to the base fluids. Finally, an influence of nanoparticles on the start of laminar-turbulent transition was examined.

Effect of Al2O3 nanoparticles and strontium addition on structural, mechanical and tribological properties of Zn25Al3Si alloy

Nanocomposites were synthesized via compocasting using Zn25Al3Si and Zn25Al3Si0.03Sr alloys as the matrices and nanoparticles of Al2O3 (1 wt%) as the reinforcement. Structure of the nanocomposites was examined, and their basic mechanical and tribological properties were tested. Distribution of primary silicon particles in the structure of nanocomposites has been improved compared to their distribution in the Zn25Al3Si matrix alloy due to the presence of Al2O3 nanoparticles and strontium. The primary silicon particles in the structure of the nanocomposites were found to be more fine-grained compared to the same particles in the structure of the as-cast Zn25Al3Si alloy. Tested mechanical properties of the nanocomposite with Zn25Al3Si alloy matrix are improved, compared to the matrix alloy. The nanocomposite with Zn25Al3Si0.03Sr alloy matrix is characterized with slightly higher value of compressive yield strength and a slightly lower hardness value compared to the as-cast Zn25Al3Si alloy. Both nanocomposites showed lower wear rate and higher coefficient of friction, compared to the matrix alloy, in sliding under the boundary lubricating regime. However, the nanocomposite with Zn25Al3Si alloy matrix showed better tribological properties than the nanocomposite with Zn25Al3Si0.03Sr alloy matrix.

Electron backscattered diffraction analysis of friction stir processed nanocomposites produced via spark plasma sintering.

In the present study, Spark Plasma Sintered (SPSed) aluminium matrix composites were severely deformed through Friction stir processing (FSP). Pure aluminium powders and bimodal sized Al2 O3 particles (80 nm and 25 μm) were firstly mixed by ball milling and then consolidated by spark plasma sintering. The effect of the heat input as well the bimodal particle size of the alumina on the materials' microstructure and texture development was evaluated by electron back scattered diffraction (EBSD) analysis. The EBSD analysis clearly showed that the SPSed nanocomposites possessed bimodal aluminium matrix grain structure as well as a crystallography characterised by random texture. In addition, microstructural examination revealed that the partial recrystallisation occurred during SPS for all the nanocomposites. Also, it is revealed that the Zener pinning effect of Al2 O3 nanoparticles retarded recrystallised grain growth following recrystallisation during FSP and then leading to grain refinement of the aluminium. The results revealed that the heat generated during FSP has a remarkable effect on the grain distribution as well as on the crystallographic orientation. Also, a mixture of {112} <110> shear elements and an ideal strong B/B¯ component were observed. The microstructural changes, occurred during FSP in the stir zone region for Al-Al2 O3 nanocomposites, were attributed to both the discontinuous along with the continuous recrystallisation (DDRX/CDRX). It should be pointed out that with increasing the heat input, recrystallised grains portion increased.

Structural, morphological, thermal, dielectric, and electrical properties of alumina nanoparticles filled PVA–PVP blend matrix‐based polymer nanocomposites

Alumina (Al2O3) nanoparticles filled poly(vinyl alcohol) (PVA) and poly(vinyl pyrrolidone) (PVP) blend matrix (50/50 wt%) based polymer nanocomposite (PNC) films (i.e., [PVA–PVP]–x wt% Al2O3; x = 0, 1, 3, and 5) have been prepared by solution‐cast method. X‐ray diffraction study has confirmed that the structures of these PNC materials are predominantly amorphous. The formation of miscible blend, polymer–polymer and polymer–nanoparticle interactions, and the effect of Al2O3 nanoparticles on the thermal properties of PVA–PVP blend matrix have been examined by Fourier transform infrared, differential scanning calorimetry and scanning electron microscopy measurements of the PNC films. The dielectric and electrical spectra of these PNC films have been measured from 20 Hz to 1 MHz using dielectric relaxation spectroscopy. It has been found that the dispersion of merely 1 wt% Al2O3 nanoparticles in the PVA–PVP blend matrix significantly reduces the crystalline phase and enhance the melting phase transition temperature of the PNC material, while the dielectric permittivity greatly decrease due to nano confinement effect. The real parts of dielectric permittivity and the impedance of these PNC films decrease linearly with the increase of the frequency, whereas the ac electrical conductivity has increased. A nonlinear increase of dielectric permittivity has been found with an increase of the temperature of PNC film and its dc electrical conductivity obeys the Arrhenius behavior. The dielectric and electrical properties of these PNC materials confirm their suitability as flexible nanodielectric of frequency tunable permittivity. POLYM. COMPOS., 39:E1788–E1799, 2018. © 2018 Society of Plastics Engineers