Evolution of single-particle morphology and composition from typical bituminous coal combustion under different temperatures

Phase-Field Modeling and Simulations of Lipid Membranes Coupling Composition with Membrane Mechanical Properties

Simulations of the Morphological Evolution of Lipid Bilayer Membranes Using a Phase-Field Method

Simultaneous evolutions in composition, structure, morphology, and upconversion luminescence of BiOxFy:Yb/Er microcrystals and their application for ratiometric temperature sensing

The biomorphic Silicon Carbide (BioSiC) ceramic with highly interconnected porous three-dimensional (3D) structure was fabricated by utilizing balsa wood cellulose nanofibers aerogel as the biotemplate and polycarbosilane (PCS) as the preceramic precursor. Evolution of morphology, composition, and pore properties from untreated wood to porous BioSiC was investigated systemically. The shrinkage and weight gain during pyrolysis was discussed. It was found that the structure of as-synthesized BioSiC was related to the microstructure of wood aerogel template and the concentration of PCS precursor. The proper microstructure of cellulose skeleton which was essential for the infiltration process could obtained by removing lignin and hemicellulose appropriately. The optimum PCS content was 40 wt. % for easy infiltration and proper SiC content. The results revealed that the dredged skeleton of cellulose was reproduced perfectly by PCS ceramization. The obtained BioSiC presented high porosity (61.03%) and low density (0.86 g/cm3) with good Darcy permeability (19.22 mD).

Electrocatalytic oxygen evolution activities of metal chalcogenides and phosphides: Fundamentals, origins, and future strategies

In this study, nanocrystalline (NC) aluminum (Al) and magnesium (Mg)-doped Al bulk components were fabricated using a hybrid manufacturing process that combines cryomilling and high-pressure cold spray (HPCS) additive deposition techniques. Yttria-stabilized zirconia (YSZ) was also added during the HPCS process to improve deposition efficiency and build-up thickness via peening. The evolution of morphology, crystallite size, and elemental composition of both cryomilled powders and cold-sprayed (CS’ed) components was systematically characterized using X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM). Mechanical characterization was performed using Vickers microhardness and uniaxial tensile testing, while the tribological behavior was assessed using sliding wear tests under dry/lubricated conditions. XRD analysis revealed that increased cryomilling duration led to significant crystallite refinement, which directly correlated with enhanced hardness and strength. This mechanical strengthening was accompanied by an increase in coefficient of friction (COF) and lower wear rates. The results also showed that the Mg-doped Al exhibited superior hardness, tensile strength, and tribological performance compared to pure Al. The study further explores the underlying mechanisms responsible for these enhancements, highlighting the potential of solute-assisted grain boundary stabilization in tailoring high-performance NC Al alloys.

pH-assisted shape-controlled synthesis of homogeneous hybrid CdS-cystine composites

Construction of γ-MnS/α-MnS hetero-phase junction for high-performance sodium-ion batteries

The Aluminium Bronzes are successfully used in heat exchanger tubes, particularly in chemical and oil industries, where they are subjected to sligthly acid conditions or higher temperatures and stresses than other copper alloys allow. For a maximun resistance to corrosion an understanding of the effects of composition and metallurgical structure is desirable. This work study the different precipitates appearing in ASTM B148-C95800 complex Al bronze alloy, due to the structural development in as cast,forged and heat treated conditions, the presence of Fe and Ni as additions enhance the presence of many different precipitates all over the structure, changing the corrosion resistance and mechanical properties. In this type of alloy the non-stoichiometric β phase breaks down progresively during cooling from high temperatures: 750° - 950°C to give a finely divided iron - nickel - aluminium “kappa” (κ) phase in a copper rich (α) matrix. Such α + κ alloys generally can contains small quantity of β and none γ2 (deleterious to all properties), showing excellent corrosion resistance combined with high tensile strength.

Microstructure and optical dispersion characterization of nanocomposite sol–gel TiO2–SiO2 thin films with different compositions

Formation of nanocrystalline TiN at low temperatures was demonstrated by combining Pulsed Laser Deposition (PLD) and ion implantation techniques. The Ti films of nominal thickness approximatly 250 nm were deposited at a substrate temperature of 200 degrees C by ablating a high pure titanium target in UHV conditions using a nanosecond pulsed Nd:YAG laser operating at 1064 nm. These films were implanted with 100 keV N+ ions with fluence ranging from 1.0 x 10(16) ions/cm2 to 1.0 x 10(17) ions/cm2 The structural, compositional and morphological evolutions were tracked using Transmission Electron Microscopy (TEM), Secondary Ion Mass Spectrometry (SIMS) and Atomic Force Microscopy (AFM), respectively. TEM analysis revealed that the as-deposited titanium film is an fcc phase. With increasing ion fluence, its structure becomes amorphous phase before precipitation of nanocrystalline fcc TIN phase. Compositional depth profiles obtained from SIMS have shown the extent of nitrogen concentration gradient in the implantation zone. Both as-deposited and ion implanted films showed much higher hardness as compared to the bulk titanium. AFM studies revealed a gradual increase in surface roughness leading to surface patterning with increase in ion fluence.

Phase engineering of Cu@Cu2O core-shell nanospheres for boosting tandem electrochemical CO2 reduction to C2+ products

Characterization of highly corrosion-resistant nanocrystalline Ni coating electrodeposited on Mg–Nd–Zn–Zr alloy from a eutectic-based ionic liquid

This study is focused on characterization of microstructural changes linked to deformation and crack formation mechanisms in duplex Ti-6Al-4V specimens used in displacement controlled fretting only experiments. In particular, the effect of slip displacement amplitude and number of fretting cycles on the evolution of grain morphology, grain orientation, misorientation distribution, composition, and microhardness is investigated using electron backscatter diffraction (EBSD), energy dispersive X-ray analysis (EDX) and nanoindentation. A strong basal microtexture and significant oxygen diffusion were observed in the Ti-6Al-4V specimen that exhibited the most significant cracking. A critical slip amplitude threshold may exist for which a combination of mechanisms such as plastic deformation, grain reorientation, and oxygen diffusion occur during fretting that make conditions ideal for crack formation. The results provide insights for development and validation of computational crystal plasticity models with application to fretting and sliding contact problems. New fretting damage assessment measures have also been identified and have application for components that suffer from fretting wear and/or fatigue related failures.

This study is focused on characterization of microstructural changes linked to deformation and crack formation mechanisms in duplex Ti-6Al-4V specimens used in displacement controlled fretting-only experiments. In particular, the effect of slip displacement amplitude and number of fretting cycles on the evolution of grain morphology, grain orientation, misorientation distribution, composition, and microhardness is investigated using electron backscatter diffraction (EBSD), energy dispersive X-ray analysis (EDX), and nanoindentation. A strong basal microtexture and significant oxygen diffusion were observed in the Ti-6Al-4V specimen that exhibited the most significant cracking. A critical slip amplitude threshold may exist for which a combination of mechanisms, such as plastic deformation, grain reorientation, and oxygen diffusion, occur during fretting that make conditions ideal for crack formation. The results provide insights for development and validation of computational crystal plasticity models with application to fretting and sliding contact problems. New fretting damage-assessment measures have also been identified and have application for components that suffer from fretting wear and/or fatigue related failures.