Bismuth-based nanoparticles and nanocomposites: synthesis and applications.

In the vast landscape of materials science, bismuth emerges as a compelling element with unique properties and diverse applications. Its intriguing characteristics and advancements in nanotechnology have propelled bismuth-based nanoparticles to the forefront of scientific exploration, promising breakthroughs in various disciplines. This comprehensive review explores diverse methods for synthesizing bismuth-based nanoparticles and nanocomposites, ranging from conventional approaches such as hydrothermal and sol-gel to innovative techniques such as microwave-assisted, microemulsion, and green synthesis.

Plugging performance and mechanism of an OBDF oil-absorbing resin (MMA-SMA-St) plugging agent.

To treat the issue of increased resource wastage due to the higher plugging tendencies of oil-based drilling fluids (OBDF) relative to water-based drilling fluids, this study synthesized a ternary composite oil-absorbing resin and optimized its synthesis parameters. The influence of temperature variations on the resin's oil absorption capacity was assessed. Techniques such as infrared spectroscopy, scanning electron microscopy, TGA-DSC measurements, crosslinking degree analysis, contact angle analysis, X-ray photoelectron spectrometry analysis and examination of the resin's plugging mechanism were employed to investigate its molecular structure, oil absorption properties, and plugging efficiency.

Molecular dynamics study on defect evolution during the plastic deformation of nickel-based superalloy GH4169 single crystal under different rolling temperatures.

Nickel-based superalloy GH4169 is widely used as an important material in the aviation field. The rolling forming process can improve its surface quality and performance. Therefore, conducting an extensive investigation into the microscopic plastic deformation defect evolution process of nickel-based single crystal alloys during the rolling process is crucial.

Preparation and characterization of a self-suspending ultra-low density proppant.

A self-suspending ultra-low density proppant (UDP) was developed based on the polymerization of the unsaturated carbon double bond. Its performance was characterized by FT-IR and SEM, and the sphericity and roundness, diameter distribution, density, mechanical properties, the conductivity of the propped fracture, and mass loss of different fluids were measured. The test results indicated that the UDP no longer contained the unsaturated carbon double bond and the polymerization took place in the raw material.

Promoting the stability and adsorptive capacity of FeO-embedded expanded graphite with an aminopropyltriethoxysilane-polydopamine coating for the removal of copper(ii) from water.

In this study, three magnetic graphites, namely, EGF, GAF, and GFA + KH550, were prepared, which were loaded either with FeO or with FeO and PDA or with FeO, PDA, and KH550 onto expanded graphite. ATR-FTIR, XRD, XPS, SEM, TEM, and TGA characterization results showed that EGF, GAF, and GFA + KH550 were successfully prepared. Under the same initial copper concentration, the removal rates of copper ions by EGF, GFA, and GFA + KH550 were 86.

Theoretical design of bis-azole derivatives for energetic compounds.

Bis-azole derivatives are a new class of energetic materials with features that include high nitrogen content, high heat of formation (HOF), high detonation performance and insensitivity to external stimuli. In this paper, 599 new bis-azole compounds were designed in a high-throughput fashion using bis-azole molecules of high density and high thermal decomposition temperature as the basic structure, and high energy groups such as nitro (-NO) and amino groups (-NH) as substituents. The molecular geometry optimization and vibration frequency analysis were performed using the DFT-B3LYP/6-311++G(d,p) method.

A study on the local corrosion behavior and mechanism of electroless Ni-P coatings under flow by using a wire beam electrode.

The local corrosion behavior and mechanism of Ni-P coatings in a 3.5 wt% sodium chloride solution with different flow speeds (0 m s, 0.5 m s, 1 m s) were investigated through a wire beam electrode (WBE) with morphological, elemental and electrochemical analyses as well as numerical simulations.

Enhancing the Vickers hardness, melting point and thermodynamic properties of hafnium dodecaboride.

Although HfB is a promising surperhard material because of the boron cuboctahedron cage, the Vickers hardness of HfB remains controversial. We apply first-principles calculations to investigate the influence of a transition metal on the structural stability, Vickers hardness and thermodynamic properties of HfB. The Vickers hardness of HfB is 39.

Curing kinetics of phenolphthalein based polyphosphazene towards thermal stability and flame retardancy of polybenzoxazine.

Phenolphthalein type polyphosphazene (PZPT) microspheres were synthesized by an ultrasound assisted precipitation polymerization method, and their structures were confirmed by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. Benzoxazine/PZPT (Ba/PZPT) hybrid materials were fabricated and cured to prepare polybenzoxazine/PZPT (PBa/PZPT) composites. The effects of PZPT microspheres on the curing kinetics and behaviors of Ba were systematically analyzed and supported by differential scanning calorimetry (DSC) and FTIR.

Effect of molecular flexibility on the rheological and filtration properties of synthetic polymers used as fluid loss additives in water-based drilling fluid.

The effect of molecular flexibility on the rheological and filtration properties of synthetic polymers used as fluid loss additives in water-based drilling fluid was investigated. A new synthetic polymer (PAANS) comprising acrylamide (AM), 2-acrylamido-2-methyl-1-propane sulfonic acid (AMPS), -vinyl-2-pyrrolidone (NVP) and potassium 2,5-dihydroxybenzenesulfonate (DHBS) was synthesized, in which phenyl groups were introduced in the backbone. Two other comparative polymers, PAAN and PAANS, were also prepared following the same synthesis procedure.

Insight into the electronic and thermodynamic properties of NbSi from first-principles calculations.

The electronic and thermodynamic properties of NbSi with four structures (C40, C11, C54 and C49) were studied in terms of first-principle calculations. The band structure and density of states of four NbSi are calculated. Those disilicides show electronic properties because the band gap between the conduction band and the valence band is near the Fermi level.

Simultaneous enhancement of electrical conductivity and interlaminar fracture toughness of carbon fiber/epoxy composites using plasma-treated conductive thermoplastic film interleaves.

Multiwalled carbon nanotube (MWCNT)-doped polyamide 12 (PA12) films with various nanofiller loadings were prepared a solution casting method to simultaneously improve the electrical conductivity and fracture toughness of carbon fiber/epoxy (CF/EP) composites. The films were interleaved between CF/EP prepreg layers and melted to bond with the matrix during the curing process. To improve the interfacial compatibility and adhesion between the conductive thermoplastic films (CTFs) and the epoxy matrix, the CTFs were perforated and then subjected to a low temperature oxygen plasma treatment before interleaving.

DFT prediction of a novel molybdenum tetraboride superhard material.

Although transition metal borides (TMBs) are promising superhard materials, the research and development of new TMB superhard materials is still a great challenge. Naturally, the Vickers hardness of TMBs is related to the 3D-network chemical bonding, in addition to the valence electron density and covalent bonds. In this paper, we apply calculations to explore the structural stability, Vickers hardness and hardening mechanism of MoB tetraboride.

Predicting sulfur solubility in hydrogen sulfide, carbon dioxide, and methane with an improved thermodynamic model.

During development of high sulfur-content natural gas fields, gaseous sulfur is likely to precipitate and deposit in the reservoir and transmission pipelines owing to changes in the temperature, pressure, and gas components. It is important to accurately predict the elemental sulfur solubility in hydrogen sulfide, carbon dioxide, and methane because these are the three main components of high-sulfur-content natural gas. The binary interaction coefficients between sulfur and hydrogen sulfide, carbon dioxide, and methane are the key parameters for predicting the sulfur solubility with a thermodynamic model.

Synthesis and characterization of comb-shaped copolymer as a filtration reducer and comparison with counterparts.

A comb-shaped copolymer of 2-acrylamide-2-methyl propane sulfonic acid (AMPS), allyl polyoxyethylene ether (APEG), -vinyl-2-pyrrolidone (NVP) and sodium styrene sulfonate (SSS) was synthesized by free-radical polymerization. The structure of the comb-shaped copolymer was characterized by Fourier transform infrared (FTIR) spectroscopy, and its molecular weight was determined by gel permeation chromatography (GPC). FTIR measurements and environmental scanning electron microscopy (ESEM) analysis were used to characterize the working mechanism of different filtrate loss reducers.