The Experts below are selected from a list of 42 Experts worldwide ranked by ideXlab platform
Sherif El Safty - One of the best experts on this subject based on the ideXlab platform.
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synthesis of ultrahydrophobic and thermally stable inorganic organic nanocomposites for self cleaning foul release coatings
Chemical Engineering Journal, 2017Co-Authors: Mohamed S Selim, Mohamed A Shenashen, Ahmed Elmarakbi, Nesreen A Fatthallah, Shinichi Hasegawa, Sherif El SaftyAbstract:A conformal novel and low-cost series of elastomeric high-molecular weight polydimethylsiloxane (PDMS)/controlled SiO2-doped ZnO nanocomposites were accurately synthesized via hydrosilation curing. Different concentrations of doped nanospheres were inserted in the nanocomposite via in situ technique. The synergetic effect of micronanobinary scale roughness and controlled fouling on different kinds of substrates was determined. The hydrophobicity, roughness, and free-energy properties were investigated as self-cleaning and fouling release (FR) factors. The nanocomposites were also subjected to various tests on surface adhesion and mechanical properties, such as impact, T-bending, crosscut, and abrasion resistance. The anticorrosive features of nanocomposites were investigated through salt spray test. The mechanical tests and salt spray test exhibited the most profound effect by incorporation of 0.5% SiO2-doped ZnO nanospheres, indicating well distributed SiO2-doped ZnO nanofillers (0.5%). Results indicate that the nanocomposites retained the Nanostructure Characteristics under thermal and irradiation treatments. Furthermore, microfoulants of chosen bacterial progenies were applied on vinyl-ended PDMS/spherical SiO2-doped ZnO nanocomposites for about one month of laboratory assessments. These studies indicated the importance of good distribution of doped nanofillers on enhancing FR ability in the modeled nanocoatings. A particular increase in contact angle (CA, 167° ± 2) and the decrease in free energy of surface (9.24 mN/m) and microroughness indicated the FR functionality of these nanocomposites. Our findings show evidence that the developed nanocomposites demonstrated inert and nonwettable properties, superior physical Characteristics, surface innerness and lotus effect, long-term durability under UV radiation, and thermal stability and resistance against a wide range of pH solutions, making them promising as efficient environment-friendly self-cleaning for coating of ship hulls.
Mohamed S Selim - One of the best experts on this subject based on the ideXlab platform.
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synthesis of ultrahydrophobic and thermally stable inorganic organic nanocomposites for self cleaning foul release coatings
Chemical Engineering Journal, 2017Co-Authors: Mohamed S Selim, Mohamed A Shenashen, Ahmed Elmarakbi, Nesreen A Fatthallah, Shinichi Hasegawa, Sherif El SaftyAbstract:A conformal novel and low-cost series of elastomeric high-molecular weight polydimethylsiloxane (PDMS)/controlled SiO2-doped ZnO nanocomposites were accurately synthesized via hydrosilation curing. Different concentrations of doped nanospheres were inserted in the nanocomposite via in situ technique. The synergetic effect of micronanobinary scale roughness and controlled fouling on different kinds of substrates was determined. The hydrophobicity, roughness, and free-energy properties were investigated as self-cleaning and fouling release (FR) factors. The nanocomposites were also subjected to various tests on surface adhesion and mechanical properties, such as impact, T-bending, crosscut, and abrasion resistance. The anticorrosive features of nanocomposites were investigated through salt spray test. The mechanical tests and salt spray test exhibited the most profound effect by incorporation of 0.5% SiO2-doped ZnO nanospheres, indicating well distributed SiO2-doped ZnO nanofillers (0.5%). Results indicate that the nanocomposites retained the Nanostructure Characteristics under thermal and irradiation treatments. Furthermore, microfoulants of chosen bacterial progenies were applied on vinyl-ended PDMS/spherical SiO2-doped ZnO nanocomposites for about one month of laboratory assessments. These studies indicated the importance of good distribution of doped nanofillers on enhancing FR ability in the modeled nanocoatings. A particular increase in contact angle (CA, 167° ± 2) and the decrease in free energy of surface (9.24 mN/m) and microroughness indicated the FR functionality of these nanocomposites. Our findings show evidence that the developed nanocomposites demonstrated inert and nonwettable properties, superior physical Characteristics, surface innerness and lotus effect, long-term durability under UV radiation, and thermal stability and resistance against a wide range of pH solutions, making them promising as efficient environment-friendly self-cleaning for coating of ship hulls.
Hanyu Chen - One of the best experts on this subject based on the ideXlab platform.
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a comprehensive study of fuel composition combustion and soot Nanostructure Characteristics of a diesel light hydrocarbons premixed charge compression ignition engine
Fuel, 2020Co-Authors: Hanyu Chen, Xi Wang, Zhixiang PanAbstract:Abstract The present research concentrates on the fuel properties and engine operating conditions on combustion and emission Characteristics especially for morphology and nano-structure of a light hydrocarbons PCCI engine. The experiments were conducted by using gas chromatography-mass spectrometry, thermogravimetric analysis and high-resolution transmission electron microscopy. Additionally, the performance, combustion and gaseous pollutant emissions Characteristics were also performed. The results indicate that the carbon chain length of main compounds in light hydrocarbons sample is shorter and the volatile matter content is higher. TG/DTG curves of light hydrocarbons move to a lower temperature region compared to diesel, which is due to lower decomposition temperature and higher volatility of light hydrocarbons. The performance Characteristics show that BSFC is higher and BTE is lower in light hydrocarbons PCCI engine compared to conventional diesel engine. The combustion and emission Characteristics show that the in-cylinder peak pressure of light hydrocarbons PCCI engine is reduced by 18.1%, and the pressure rise rate and heat release rate present a consistent variation trend compared to conventional diesel engine. Light hydrocarbons PCCI engine exhibits higher THC emission with respect to different engine load, while CO and NOx emissions are lower. Compared with conventional diesel engine, the soot aggregate of light hydrocarbons PCCI engine exhibits more sparse, and it appears more chain-like. Additionally, the primary particles in light hydrocarbons PCCI engine represent more ordered graphitic and fullerenic Nanostructure.
Ristovski Zoran - One of the best experts on this subject based on the ideXlab platform.
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The impact of chemical composition of oxygenated fuels on morphology and Nanostructure of soot particles
'Elsevier BV', 2020Co-Authors: Verma Puneet, Pickering Edmund, Jafari Mohammad, Stevanovic Svetlana, Brown Richard, Rahman S M Ashrafur, Dowell Ashley, Ristovski ZoranAbstract:Over the years, oxygenated fuels such as biodiesel and alcohol fuels have been useful in reducing particulate matter (PM) emissions of diesel engines. The presence of oxygen in the fuel impacts the soot oxidation process and thus the morphology and nanostructural Characteristics of soot particles change. The Nanostructure Characteristics of soot particles hold an importance for their oxidation reactivity and toxicity. Higher reactivity and exposure of soot particles to oxygen will affect the regeneration and filtration efficiency of diesel particulate filters. In this study, we investigate the impact of oxygen functional groups on morphology and Nanostructure of soot particles by blending different types of essential oil in diesel. The test fuels were prepared by mixing orange oil, tea tree oil, eucalyptus oil and coconut biodiesel to keep an overall oxygen content of 0 and 2.2%. Transmission electron microscopy was used to investigate the physical changes in the Nanostructure of soot particles. The primary particle diameter decreases, and fractal dimension of soot aggregates increases for oxygenated fuels. Microscopy reveals that the arrangement of carbon lamellae within the soot particles changes significantly with use of oxygenated as observed by the changes in fringe length, fringe tortuosity and fringe separation distance. Lower fringe length, higher fringe tortuosity and fringe separation distance shows disordered arrangement of carbon layers with more possibility of oxygen attack. The different structural Characteristics for oils having same oxygen content shows that formation and structure of soot particles strongly depend upon chemical structure and composition of the fuel
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Influence of fuel-oxygen content on morphology and Nanostructure of soot particles
'Elsevier BV', 2019Co-Authors: Verma Puneet, Pickering Edmund, Jafari Mohammad, Yi Guo, Stevanovic Svetlana, Fernando Joseph, Golberg Dmitri, Brooks Peter, Brown Richard, Ristovski ZoranAbstract:The share of biofuels in the fuel market has increased over the last several decades. This is related to their potential to reduce the emissions including particulate matter. It has been frequently reported that the fuel oxygen content is the main reason for the reduction in particulate matter emissions. To understand the effect of fuel oxygen content on morphology and Nanostructure Characteristics of soot particles, different fuels such as diesel, coconut biodiesel and triacetin were tested in a diesel engine with various mixing proportions. The fuel blending was done in such a way that overall oxygen content of fuel was kept in range of 0% to 14% (wt.%). The soot particles were sampled from the engine exhaust system and analysed with a transmission electron microscope (TEM) at low and high spatial resolution. The TEM images were post-processed with the help of an in-house developed image analysis program to determine the morphology and Nanostructure Characteristics. The results show that oxygenated fuel blends emit smaller sized soot particles forming compact aggregates. The investigation of the internal structure of soot particles show disordered arrangement of graphene layers for fuels up to 11.01% fuel oxygen content (pure biodiesel); however, the opposite trend was observed for fuel blends with triacetin which could be related to the presence of oxygen in a different chemical functional group
Malek A H Muhi - One of the best experts on this subject based on the ideXlab platform.
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Nanostructure Characteristics of bi2o3 al2o3 thin films and the annealing temperature effect on morphological optical and mechanical properties
Superlattices and Microstructures, 2020Co-Authors: Kadhim R Gbashi, Ammar T Salih, Aus A Najim, Malek A H MuhiAbstract:Abstract In this work, Bi2O3:Al2O3 thin films were prepared on a glass substrate by pulsed laser deposition (PLD) then thermally treated by annealing at temperatures 300, 400, and 500 °C. XRD analysis reveals that all films have a polycrystalline structure of Bi2Al4O9 with the presence of secondary phases of Bi2O3 and Al2O3, the degree of crystallinity increased with annealing temperature, we observed a significant decrease in crystallite size after annealing. SEM and AFM measurements show the films are homogeneous and free of voids and cracks with spherical nanoparticles and relatively high roughness. The optical Characteristics show a redshift in the bandgap with increasing annealing temperature. Vickers micro-hardness increased with annealing temperature, the optimum condition is recorded in the films annealed at 500 °C where the highest micro-hardness is recorded and found to be comparable to those of soda-lime glass. These Characteristics prove this composite is a promising material in the glass manufacturing process, optoelectronics, and smart windows.
