Search Results (91)

The Paleozoic strata in the Kongxi slope zone of the Dagang oilfield, Huanghua depression, exhibit significant hydrocarbon exploration potential. Although bitumen is widely present in the Paleozoic reservoirs, its formation process and genetic mechanism remain poorly understood. This study systematically investigates the occurrence, maturity, origin, and evolutionary processes of Paleozoic reservoir bitumen in the Kongxi zone through core observations, microscopic analyses, geochemical testing, and thermal simulation experiments. The results reveal that reservoir bitumen in the Kongxi slope zone is characteristically black with medium to medium-high maturity. In core samples, bitumen occurs as bands, veins, lines, and dispersions within partially filled fractures and breccia pores. Petrographic analysis shows bitumen partially occupying intergranular pores and intergranular pores of Lower Paleozoic carbonate rocks and Upper Paleozoic sandstones, either as complete or partial pore fills. Additional bitumen occurrences include strip-like deposits along microfractures and as bitumen inclusions. Dark brown bitumen fractions were also identified in crude oil separates. The formation and evolution of Paleozoic reservoir bitumen in the Kongxi slope zone occurred in two main stages. The first-stage bitumen originated from Ordovician marine hydrocarbon source rocks, subsequently undergoing oxidative water washing and biodegradation during tectonic uplift stage. This bitumen retains compositional affinity with crude oils from Lower Paleozoic carbonate rocks. Second-stage bitumen formed through the thermal evolution of Carboniferous crude oil during deeper burial, showing compositional similarities with Carboniferous source rocks and their oil. This two-stage bitumen evolution indicates charging events in the Paleozoic reservoirs. While early uplift and exposure destroyed some paleo-reservoirs, unexposed areas within the Dagang oilfield may still contain preserved primary accumulations. Furthermore, second-stage hydrocarbon, dominated condensates derived from Carboniferous coal-bearing sequences since the Eocene, experienced limited thermal evolution to form some bitumen. These condensate accumulations remain the primary exploration target in the Paleozoic Formations. Full article

Oil spills represent a significant environmental hazard, particularly in marine ecosystems, where their impacts extend to coastal infrastructure, biodiversity, and economic activities. This study utilizes GNOME v.47.2 (General NOAA Operational Modeling Environment) and ADIOS2 v.2.10.2 (Automated Data Inquiry for Oil Spills) to simulate and analyze oil spill dynamics in the Romanian sector of the Black Sea, focusing on trajectory prediction, hydrocarbon weathering, and shoreline contamination risk assessment. The research explores multiple spill scenarios involving different hydrocarbon types (light vs. heavy oils), vessel dynamics, and real-time environmental variables (wind, currents, temperature). The findings reveal that lighter hydrocarbons (e.g., gasoline, aviation fuel) tend to evaporate quickly, while heavier fractions (e.g., crude oil, fuel oil #6) persist in the marine environment and pose a higher risk of coastal pollution. In the first case study, a spill of 10,000 metric tons of medium oil (Arabian Medium EXXON) was simulated using GNOME v.47.2, showing that after 22 h, the slick reached the shoreline. Under forecasted hydro-meteorological conditions, 27% evaporated, 1% dispersed, and 72% remained for mechanical or chemical intervention. In the second simulation, 10,000 metric tons of gasoline were released, and within 6 h, 98% evaporated, with only minor residues reaching the shore. A real-world validation case was also conducted using the December 2024 Kerch Strait oil spill incident, where the model accurately predicted the early arrival of light fractions and delayed coastal contamination by fuel oil carried by subsurface currents. These results emphasize the need for future research focused on the vertical dispersion dynamics of heavier hydrocarbon fractions. Full article

Phase change materials (PCMs) have the advantage of using the latent thermal heat as energy storage. Coconut oil (CO) has attracted much attention as PCM due to its high stability against oxidation. Although the viscosity of CO-based dispersions has extensively been studied, little research has been performed on time-dependent flow behaviors. In this work, the rheological properties of fumed silica dispersed in CO at fractions of 1, 2, 3, and 4 vol.% were investigated. All suspensions showed shear-thinning behavior, which became more Newtonian at temperatures above the phase change. The 3 and 4 vol.% suspensions showed gel-like microstructures. The thixotropic properties of the 3 vol.% suspension at 30 °C and 35 °C were mainly studied through stepwise changes in the shear rate. The results were consistent with thixotropic behavior, with a complete recovery of the microstructure. The sweep frequency of this sample demonstrated the dominance of the elastic modulus at both temperatures. Therefore, a thixoelastic nature of this gel could be inferred. This gel-like material flowed under high stress, providing superior thermal damping capabilities compared to conventional fluids. A reduction of 8.65 °C was confirmed after 30 min. of the laptop power supply operation. Full article

The Baltic Sea blue mussel (Mytilus trossulus) plays a crucial role in this brackish water ecosystem, filtering water and accumulating pollutants. This study investigated how exposure to crude oil and dispersants affects the microbiome of M. trossulus at two salinities (5.6 and 15) over 21 days. Results showed that dispersant use significantly increased the accumulation of polycyclic aromatic hydrocarbons (PAHs) in mussel tissues, particularly at lower salinity. The microbial communities in gills and digestive glands were notably affected, with shifts towards hydrocarbon-degrading bacteria like Shewanella and Acinetobacter in samples exposed to chemically enhanced water accommodated fraction of crude oil (CEWAF). Salinity was a key factor in determining both PAH accumulation and microbial diversity, with lower salinity leading to reduced bacterial diversity in dispersant treatments. This study highlights the need for a cautious use of dispersants in sensitive environments like the Baltic Sea, emphasizing the ecological implications of altered microbial communities. Full article

This study investigated the capabilities of Yarrowia lipolytica strains to grow in media with different hydrophobic wastes from the meat industry. The yeast growth, cellular lipid accumulation, production of lipases, and degree of utilization of liquid and solid lipid wastes were studied in shaken cultures in media with organic and inorganic nitrogen sources. The effects of the type of waste, initial concentration of carbon source, Yarrowia strain, and inoculum size were investigated in two experimental sets using the Latin Square 5 × 5 design method. Post-frying rapeseed oil from chicken frying was selected as the carbon source to promote biomass growth. In contrast, the solid lipid fraction from meat broths promoted efficient lipid accumulation and yeast lipolytic activity. An initial concentration of the carbon source at 8% m/v stimulated efficient lipid biosynthesis and lipase production, while 2.5% v/v inoculum provided optimal conditions for the growth and utilization of hydrophobic substrates. No significant differences were observed in the particle dispersion of the liquid and solid wastes in the culture media (span = 2.51–3.23). The maximum emulsification index (62%) was observed in the culture of the Y. lipolytica KKP 323 strain in the medium with post-frying rapeseed oil from chicken frying, which was correlated with biosurfactant synthesis. It was concluded that the type of waste, its structure, and its composition affected various physiological yeast responses. Full article

This work studies the stabilization of Pickering-like emulsions using dispersions of interpolyelectrolyte complexes (IPECs) formed by chitosan (CS) and sodium alginate (ALG), two polymers from natural resources, as the aqueous phase and soybean oil as the oil phase. The ability of these bio-based IPECs to form stable emulsions was evaluated by varying the compositional ratio of CS to ALG (Z-ratio) and the oil volume fraction (ϕ_o). Turbidity, zeta potential, and dynamic light scattering measurements revealed the dependence of IPEC properties on the Z-ratio, with phase separation observed near stoichiometric ratios. Phase diagram analysis showed that stable oil-in-water (O/W) and water-in-oil (W/O) emulsions could be obtained under certain combinations of the Z-ratio and ϕ_o. Emulsion stability increased with higher Z-ratios due to increased interfacial activity of the complexes and reduced coalescence. Emulsions with high ϕ_o exhibited transitions from discrete droplets to bicontinuous interfacially jammed emulsion gels (bijels), suggesting tunable morphologies. These results highlight the potential of CHI-ALG IPECs as eco-friendly and efficient stabilizers of Pickering-like emulsions for applications in food, cosmetics and pharmaceuticals. Full article

This study investigates the rheological behavior of oil well cement pastes (OWCPs) modified with core/shell TiO₂@SiO₂ (nTS) nanoparticles and polycarboxylate-ether (PCE) superplasticizers at different temperatures (25, 45, and 60 °C). Results show that nTS particles increased static and dynamic yield stresses and the apparent viscosity of the cement slurries due to an increased solid volume fraction and reduced free water availability. The increase in the slurry dispersion by adding PCE superplasticizers enhanced the effect of the nanoparticles on the rheological parameters. Oscillation rheometry demonstrated that nTS nanoparticles enhanced the structural buildup, while PCE retarded hydration. Furthermore, slurries hydrated at 60 °C experienced higher initial values of the elastic modulus and a faster exponential increase in this rheological parameter due to the acceleration of the cement hydration. Full article

To improve lubricant performance and extend the service life of machinery, the friction reduction and anti-wear performance of nano-cerium oxide (nano-CeO₂) and nitrogen-containing heterocyclic borate (BNH2) composite additives were studied in this work, with the goal of obtaining better lubrication effects than a single additive. The results showed that the nano-CeO₂ modified with Span80 had good dispersion stability in the base oil. The optimal addition mass fractions of single nano-CeO₂ and BNH2 were 0.6 wt% and 1.0 wt%, respectively. Compared with the base oil, 0.6 wt% nano-CeO₂ reduced the coefficient of friction by 44.9% and the wear spot diameter by 27.8%, while 1.0 wt% BNH2 reduced the coefficient of friction by 49.1% and the wear spot diameter by 32.8%. Compared with the single additions of nano-CeO₂ and BNH2, the compound nano-CeO₂/BNH2 further improved the friction reduction and anti-wear performance of the lubricating oil. Compared with the base oil, the 0.8 wt% nano-CeO₂/1.0 wt% BNH2 composite additive reduced the coefficient of friction by 55.9% and the diameter of the abrasive spot by 48%. Physicochemical analysis of the wear surface revealed that the combination of nano-CeO₂ and BNH2 had excellent synergistic effects. The generated lubricant films of nano-CeO₂/BNH2 contained a chemical reactive layer of organic nitride (C–N), Fe₂O₃, FeO, and B₂O₃ and a physical adsorbent layer of CeO₂ that provided great friction reduction and anti-wear effects during friction. Full article

A detailed understanding of the interactions between wax and asphaltenes with other components of crude oils and the effect of treatments with paraffin inhibitors (PIs) and asphaltene dispersants (ADs), with a focus on identifying specific structure-activity relationships, is necessary to develop effective flow assurance strategies. The morphological and rheological consequences of treating wax and asphaltenes in oils of differing composition with a series of ADs having structural features in common with an alpha olefin-maleic anhydride (AO-MA) comb-like copolymer PI were assessed alone and in combination with said PI. Of the four ADs studied, two were identified as being effective dispersants of asphaltenes in heptane-induced instability tests and in a West Texas (WT) crude. The degree to which a low concentration of asphaltenes stabilizes wax in the absence of treatment additives is lessened in oils having greater aromatic fractions. This is because these stabilizing interactions are replaced by more energetically favorable aromatic–asphaltene interactions, increasing oil viscosity. Treatment with AD alone also reduces the extent of wax–asphaltene interactions, increasing oil viscosity. In concert with the PI, treatment with the AD having greater structural similarity with the PI appears to improve wax solubility in both the presence and absence of asphaltenes. However, the viscosity of the treated oils is greater than that of the oil treated with PI alone, while treatment with AD having lesser structural similarity with the PI does not adversely affect oil viscosity. These data suggest that rather than treating both wax and asphaltenes, AD may poison the function of the PI. These data illuminate the pitfalls of designing flow assurance additives to interact with both wax and asphaltenes and developing treatment plans. Full article

The contamination of the water bodies by diesel oil (DO) and its water-soluble fraction (WSF) represents one of the most challenging tasks in the management of polluted water streams. This paper contains data related to the synthesis and characteristics of the plum stone biochar material (PmS-B), which was made from waste plum stones (PmS), along with its possible application in the sorption of the WSF of DO from contaminated water. Techniques applied in sample characterisation and comparisons were: Elemental Organic Analysis (EOA), Scanning Electron Microscopy−Energy Dispersive X-ray Spectroscopy (SEM-EDX), Fourier Transform Infrared Spectroscopy (FTIR), pH (pH_sus) and point of zero charge (pH_pzc). In order to increase the overall efficiency of the removal process, sorption and bioremediation were subsequently combined. Firstly, PmS-B was used as a sorbent of WSF, and then the remaining solution was additionally treated with a specific consortium of microorganisms. After the first treatment phase, the initial concentration of diesel WSF was reduced by more than 90%, where most of the aromatic components of DO were removed by sorption. The sorption equilibrium results were best fitted by the Sips isotherm model, where the maximum sorption capacity was found to be 40.72 mg/g. The rest of the hydrocarbon components that remained in the solution were further subjected to the biodegradation process by a consortium of microorganisms. Microbial degradation lasted 19 days and reduced the total diesel WSF concentration to 0.46 mg/L. In order to confirm the non-toxicity of the water sample after this two-stage treatment, eco-toxicity tests based on a microbial biosensor (Aliivibrio fischeri) were applied, confirming the high efficiency of the proposed method. Full article

Consumers are concerned about employing green processing technologies and natural ingredients in different manufacturing sectors to achieve a “clean label” standard for products and minimize the hazardous impact of chemical ingredients on human health and the environment. In this study, we investigated the effects of gelatinized starch dispersions (GSDs) prepared from six plant sources (indica and japonica rice, wheat, corn, potatoes, and sweet potatoes) on the formulation and stability of oil-in-water (O/W) emulsions. The effect of gelatinization temperature and time conditions of 85–90 °C for 20 min on the interfacial tension of the two phases was observed. Emulsification was performed using a primary homogenization condition of 10,000 rpm for 5 min, followed by high-pressure homogenization at 100 MPa for five cycles. The effects of higher oil weight fractions (15–25% w/w) and storage stability at different temperatures for four weeks were also evaluated. The interfacial tension of all starch GSDs with soybean oil decreased compared with the interfacial tension between soybean oil and water as a control. The largest interfacial tension reduction was observed for the GSD from indica rice. Microstructural analysis indicated that the GSDs stabilized the O/W emulsion by coating oil droplets. Emulsions formulated using a GSD from indica rice were stable during four weeks of storage with a volume mean diameter (d_4,3) of ~1 µm, minimal viscosity change, and a negative ζ-potential. Full article

Tung oil (TO) microcapsules (MCs) with a poly(urea-formaldehyde) (PUF) shell were synthesized via one-step in situ polymerization, with the addition of graphene nanoplatelets (GNPs) (1–5 wt. %). The synergistic effects of emulsifiers between gelatin (gel) and Tween 80 were observed, with gel chosen to formulate the MCs due to its enhanced droplet stability. SEM images then displayed an increased shell roughness of the TO-GNP MCs in comparison to the pure TO MCs due to the GNP species on the shell. At the same time, high-resolution transmission electron microscopy (TEM) images also confirmed the presence of GNPs on the outer layer of the MCs, with the stacked graphene layers composed of 5–7 layers with an interlayer distance of ~0.37 nm. Cross-sectional TEM imaging of the MCs also confirmed the successful encapsulation of the GNPs in the core of the MCs. Micromanipulation measurements displayed that the 5% GNPs increased the toughness by 71% compared to the pure TO MCs, due to the reduction in the fractional free volume of the core material. When the MCs were dispersed in an epoxy coating and applied on a metallic substrate, excellent healing capacities of up to 93% were observed for the 5% GNP samples, and 87% for the pure TO MC coatings. The coatings also exhibited excellent corrosion resistance for all samples up to 7 days, with the GNP samples offering a more strenuous path for the corrosive agents. Full article

The study focuses on the flow patterns and pressure drop characteristics of three crude oils and water in a horizontal pipe. The experimental results showed that the transformation boundary of the flow pattern and phase inversion water fraction were related to the flow parameters. Comparing the three oils, it was found that the viscosity and composition of the oil also significantly influence the flow performance, which can be explained by the adsorption properties of the asphaltenes at the oil-water interface. In particular, the droplet size in water-in-oil dispersion flow was observed and measured. It showed that the water droplet size decreased with the increase of oil viscosity, the decrease of water content, the drop of temperature, and the growth of mixing velocity, probably due to higher shear stress and lower frequency of collision and coalescence between droplets. The apparent viscosity of water-in-oil emulsions was calculated by the rheological model, and the qualitative relation between flow parameters and interfacial area concentration on apparent viscosity was obtained. Taking the influence of interfacial area concentration into consideration, a simple and accurate viscosity model was established based on dimensional analysis, which is of great significance for process design in gathering and transportation systems. Full article

Organogels have importance for topical applications because they can be used to deliver drugs in a controlled and prolonged fashion. These are materials consisting of a three-dimensional network of organic molecules dispersed in a solvent. Recent studies have demonstrated that the solvent could be replaced by oils from non-conventional biologic sources. There is a diversity of not-explored species in the Amazon that are promising sources of vegetable oils with a promising composition. This study developed an organogel with buriti (Mauritia flexuosa L.f) and cacay (Caryodendron orinocense Karst.) oils, using cetostearyl alcohol as an organogelator due to its compatibility, stability, security, affordability, and it is readily available. The oils were characterized, and the organogels were synthesized by studying their crystal evolution and oil-binding capacity. The microstructure was evaluated with polarized light microscopy, fractal dimension, FTIR spectroscopy, XRD, and thermal and rheological analyses. It was found that the critical gelation concentration was higher for cacay oil as it possessed a higher amount of polyunsaturated triacylglycerols. The crystals of the buriti organogel had a smaller lamellar shape, a greater surface area, and physical and thermal stability; although, it presented a slower crystal evolution due to the low number of minor compounds and a greater number of saturated triacylglycerols. The polar fraction of the organogelators as well as triacylglycerol and minor polar compounds are important in forming crystallization nuclei. The study showed that Amazonian oils in crystallization processes form microstructures with differentiating physicochemical properties. Full article

Plant-based seafood analogs are gaining increasing popularity as replacements for traditional fish and other seafood products due to environmental (stock depletion, pollution, and bycatch issues) and health (bioaccumulated toxins, norovirus, and allergies) concerns associated with them. Several companies have launched plant-based fish products, but the market still lacks alternatives to shellfish and other sea delicacies. In this study, a plant-based sea foie gras (monkfish liver product) analog was developed using duckweed RuBisCO protein and omega-3-rich flaxseed oil to form emulsion gels. These gels consisted of a high concentration of flaxseed oil droplets dispersed within a gelled RuBisCO protein network. It was hypothesized that the high disperse phase volume fraction of the oil droplets and the heat-set gelation properties of the RuBisCO proteins would enable us to create emulsion gels that mimicked the properties of sea foie gras. A natural pigment (β-carotene) was incorporated into the oil phase of the emulsions to mimic the red-orange color of conventional sea foie gras. The structural, textural, and optical properties of real and plant-based sea foie gras analogs were characterized using scanning electron microscopy, confocal microscopy, dynamic shear rheology, texture profile analysis, and colorimetry. Emulsion gels prepared using 40% flaxseed oil and 10% RuBisCO proteins produced plant-based products that closely simulated the texture and color of the real products. Rheological analysis suggested that the oil droplets acted as active fillers within the protein gels. Our results suggest that emulsion gels may be used to create more sustainable and healthier plant-based seafood products. Full article