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Under impulse voltage, ester-based insulating oil (EO) is more likely to produce fast streamers than mineral insulating oil (MO). This paper explores the generation mechanism of fast streamers from a molecular perspective. First, the energy of EO to reach the first excited state is lower than that of MO, which is achieved through ultraviolet–visible light absorption experiments and molecular computation and is almost unaffected by the electric field. During the discharge process, photons may mainly come from molecular de-excitation, which leads to the neutral oil molecules transition and occurs photoionization. This study established a plasma photoionization model related to the change of first excitation energy and ionization energy at an electric field. Compared with MO, the electric field strength at the streamer head of EO is enhanced by the large number of charged particles produced by photoionization. The higher electric field further promotes the occurrence of photoionization, forming a positive feedback mechanism and accelerating the generation of fast streamers. The simulation results are consistent with the experimental results. It is found that field ionization is one of the main mechanisms that drives the streamers forward, and photoionization may be the cause of the generation of fast streamers in EO. [ABSTRACT FROM AUTHOR]

This study demonstrates a new green rigid polyurethane (PU) based on modified palm oil (MPO) for marine buoy applications. The bio‐polyol based on palm oil was synthesized using hydrogen peroxide and formic acid. The foam formation was by kinetic foaming reaction. The MPO‐based PU foams made with increased water content had closed cells that grew larger with water content to provide a low‐density foam. The resistance to flammability of PU foam was improved by adding triphenyl phosphate (TPP). The PU foam with increased TPP content had enlarged cells, increased water absorption and decreased compressive strength. In addition, carbon black (CB)‐containing foam had uniform, large foam cells, comparatively high density, higher compressive strength, and low water absorption. Moreover, a high CB content gave shorter extinguishing time for PU foam. The PU foams were investigated for buoyancy and compared with a commercial PU foam buoy. The commercial buoy had lower density, providing better‐floating performance than PU foam. Interestingly, CB_8 had an elevated density, but low water absorption rate, similar to the commercial buoy PU foam. The investigations showed that the PU foam from MPO is eco‐friendly, and the buoyancy performance of that foam is improved on adding TPP or CB. [ABSTRACT FROM AUTHOR]

Increasing environmental issues and depletion of fossil resources highlight the need to develop sustainable lubricant production technologies. This study endeavored to produce various biomass-derived furan diesters and evaluate their physical properties against conventional lubricants. Among the synthesized furan diesters, the THFDM-C18 diester, produced via the esterification of THFDM and oleic acid, was identified as a promising candidate for base oils due to its broad applicability as well as environmentally benign properties. Based on our experimental results, which include the hydrogenation of HMF to 2,5-tetrahydrofuran dimethanol (THFDM) using Ru/Al2O3 (achieving a 95.6% yield of THFDM) and subsequent esterification with C18-fatty acids to produce the THFDM-C18 diester using Amberlyst-15 (achieving a 91.0% yield of the THFDM-C18 diester), a simulation model was developed, which showed 62 metric tons per day of the THFDM-C18 diester. Life cycle assessment (LCA) results indicated that this process reduces CO2 emissions by 35.0% compared to fossil fuel-based synthetic lubricant production (9.84 vs. 15.15 kg CO2 eq.). The techno-economic analysis (TEA) revealed a minimum selling price (MSP) of 4.92 USD per kg, with MEG and oleic acid prices being the major cost factors. These findings highlight the potential of biomass-derived lubricants as sustainable alternatives to conventional petroleum-based products and emphasize the importance of further research to enhance process efficiency and reduce costs. [ABSTRACT FROM AUTHOR]

Timely and accurate oil well production warnings are crucial for optimizing oilfield management and enhancing economic returns. Traditional methods for predicting oil well production and early warning systems face significant limitations in terms of adaptability and accuracy. Artificial intelligence offers an effective solution to address these challenges. This study focuses on the ultra-high water cut stage in water-driven medium-to-high permeability reservoirs, where the water cut—defined as the ratio of produced water to total produced fluid—exceeds 90%. At this stage, even small fluctuations in water cut can have a significant impact on oil production, making it a critical early warning indicator. We use statistical methods to classify wells and define adaptive warning thresholds based on their unique characteristics. To further improve prediction accuracy, we introduce a Long Short-Term Memory (LSTM) model that integrates both dynamic and static well features, overcoming the limitations of traditional approaches. Field applications validate the effectiveness of the model, demonstrating reduced false alarms and missed warnings, while accurately predicting abnormal increases in water cut. The early warning system helps guide the adjustment of injection and production strategies, preventing water cut surges and improving overall well performance. Additionally, the incorporation of fracture parameters makes the model suitable for reservoirs with fractures. [ABSTRACT FROM AUTHOR]

In this study, oil sludge from Jilin Petrochemical of China was selected to carry out the Fischer assay and proximate analysis. According to the properties of the Jilin oil sludge and its pyrolysates, the material and heat balance of the pyrolysis process was deduced theoretically based on 1000 kg of received base oil sludge. The results show that the solid heat carrier method can be used in the pyrolysis of oil sludge, and a new process flow is proposed. According to the heat required and heat provided in the rotary reactor and in the fluidized bed, 5940 kg of ash was needed as a solid heat carrier, and 25 kg of liquefied petroleum gas was needed as a supplementary fuel besides the semi-coke and retorting gas. The total input heat and output heat were 13.65 GJ and 10.04 GJ. The loss was 3.61 GJ and the thermal efficiency was 73.6%. [ABSTRACT FROM AUTHOR]

The objective of this work was to develop a highly active hydrotreating catalyst for processing heavy gas oil to provide qualified feedstock for hydroisomerization or a hydrocracking unit. The NiMo/γ-Al2O3 catalysts doped with phosphate were prepared by introducing two kinds of additives, and the influencing factors for highly active hydrodenitrogenation (HDN) were revealed. TEM analysis results showed that the catalyst with a small MoS2 stack length tended to have high activity due to more active sites being exposed. Laser Raman spectroscopy demonstrated that the catalysts contained PMo12O403− metal active phases. For industrial heavy VGO feedstock, the nitrogen content can be reduced to 2 ppm with a hydrotreating process. The VI of the hydrotreated product can be improved from 132 to 145 after hydrotreatment, which is necessary to produce group III base oil as the most valuable base oil type. This work provides an insight into the high activity of hydrotreating catalysts for industrial lubricant hydroprocessing. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to try to develop new, environmentally friendly and efficient lubricating additives; study the compatibility of carbon-based additives with different base oils [Polyalphaolefin (PAO)-3, PAO-20 and NPE-2]; and explore the lubrication mechanism. Design/methodology/approach: Oleylamine modified carbon nanoparticles (CNPs-OA) were prepared and the dispersion stability of CNPs-OA in PAO-3, PAO-20 and NPE-2 base oils was investigated by transmission electron microscopy, Fourier transform infrared, thermogravimetric analysis, energy dispersive spectroscopy and X-ray photoelectron spectroscopy. Universal Mechanical Tester (UMT) platform was used to carry out experiments on the effects of different additive concentrations on the lubricating properties of base oil. Findings: The mean friction coefficient of PAO-3, PAO-20 and NPE-2 reduced by 32.8%, 10.1% and 11.4% when the adding concentration of CNPs-OA was 1.5, 2.0 and 0.5 Wt.%, respectively. Generally, The CNPs-OA exhibited the best friction-reducing and anti-wear performance in PAO-3. Originality/value: The agglomeration phenomenon of carbon nanoparticles as lubricating additive was improved by surface modification, and the lubricating effect of carbon nanoparticles in three synthetic aviation lubricating base oils was compared. [ABSTRACT FROM AUTHOR]

Purpose: Concerns over the pollution caused by internal combustion vehicles have increased owing to population and industrialization increment. Addressing the confrontations, the demand for electric vehicles (EVs) as a combustion engine substitute became necessary in responding to environmental worries from internal combustion. The development of bio lubricant in lubricating the sliding parts of EVs is required to maintain the sustainability idea and to improve the system performance, which this research tends to explore. Design/methodology/approach: In this research, the enhancement of base Jatropha oil was done using polytetrafluoroethylene (PTFE) and hexagonal boron nitrate (h-BN) as additives. Different characterization was conducted on the new formulation to ascertain its anticorrosion tendency. The wear and friction behavior of the formulations on the tribo-pairs surfaces in contact were investigated using ball on flat tribometer to determine their tribological responsiveness as mineral lubricant alternative. To explore the surface topography, surface profilometer, scanning electron microscope and energy dispersive X-ray investigations were PTFE, lubrication and EV carried out. Findings: The test's input parameters were EVs' usual load and sliding speed, and the addition concentrations for PTFE were 0.3 Wt.%, 0.4 Wt.%, 0.5 Wt.% and 0.6 Wt.%, whereas h-BN were 0.4 Wt.%, 0.8 Wt.% and 1.2 Wt.%, respectively. The study on corrosion demonstrated resistance when applied PTFE and h-BN additives in Jatropha oil. The analysis revealed that 0.5 Wt.% PTFE + 0.8 Wt.% h-BN concentrations significantly improved the tribological characteristics when compared to the base Jatropha oil. The application of formulations yielded percentage reduction of 8.67%, 10.98%, 7.34% and 7.35%, respectively, for 0.5% poly + 0.5% h-BN, 0.5% poly + 0.6% h-BN, 0.5% poly + 0.7% h-BN, 0.5% poly + 0.8% h-BN against base Jatropha oil under 20 N. Originality/value: The formulation of PTFE and h-BN for electric transmission with wear and friction effects was accomplished in this paper. The mechanism of particle diffusing at the sliding contact on tribological behavior could be examined based on the created model of operation. Peer review: The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2023-0235/ [ABSTRACT FROM AUTHOR]

This study explores the estimation of solubility-induced elemental fractionation of noble gases in hydrocarbon-based oils through existing empirical and theoretical models, complemented by a novel molecular simulation-based approach. Quantifying such fractionation is essential for a deeper understanding of fluid processes and migration in subsurface geological resources, an area currently lacking in experimental data. To address this, the research introduces a predictive model that employs the Peng-Robinson equation of state and a fugacity-coefficient-based method to assess noble gas elemental fractionation in hydrocarbons, including normal alkanes, cycloalkanes, and aromatics. However, this model struggles with precise quantitative predictions, prompting the introduction of adjusted cross-interaction parameters to enhance its performance. Furthermore, molecular simulations, in conjunction with the refined equation of state, are shown to offer a novel method for calculating noble gas fractionation coefficients across different hydrocarbon solvents. A key finding is the identification of a universal master curve, demonstrating that noble gas solubility fractionation at low pressure in simple hydrocarbon solvents can be quantitatively determined by temperature and density alone, without the need for detailed compositional information. Consequently, a new correlation is proposed for deriving elemental fractionation coefficients based solely on oil temperature and density, offering significant improvements over existing empirical methods for a wide range of temperatures. Although limitations are noted when applying this approach to oils rich in complex heavy components like resins and asphaltenes, it allows to address inconsistencies observed in traditionally used experimental correlations at high temperatures. [ABSTRACT FROM AUTHOR]

In this study we report on the influence of poly(isobutylene) (PIB) and PIB-based dispersants on the high pressure thermodynamic properties and the viscosity of a mineral base oil used in passenger vehicle transmission fluids. Density was measured over a pressure range from 10 to 35 MPa at isotherms of 298, 323, 348, 373, and 398 K using a high pressure variable-volume view cell. The density data were then correlated with the Sanchez-Lacombe Equation of State from which the thermodynamic properties of isothermal compressibility, isobaric expansively and internal pressure were derived. Viscosity was measured over a pressure range from 10 to 45 MPa at 298, 323, 248, and 373 K using a uniquely designed high pressure rotational viscometer. Viscosity data were then correlated with density according to the free volume and density-scaling formalisms to provide further insights into molecular packing and interactions. [ABSTRACT FROM AUTHOR]

The current study aims at eradicating the contaminants from waste lubricating oil by the use of discrete properties of solvents through a solvent extraction–flocculation process for reconditioning spent lubricating oil. This work also emphasizes on comparative assessment of four extracting solvents such as butan-1-ol, methyl ethyl ketone, 2-propanol, and n-hexane on overall performance of recycling waste lubricating oil to achieve higher percentage yield and better quality of refined base stock. Percentage oil yield and percentage sludge removal were explored by varying refining time from 30 min. to 90 min., refining temperature ranging from 30 to 60 °C, and solvent to used oil ratio (2:1–6:1). Result obtained from the experiment shows that when solvent to waste oil ratio increases, the percentage oil yield increases significantly from 78.97 to 84.36; 65.67 to 75.04; 73.91 to 82.45; and 52.31 to 79.50 and percentage removal of sludge significantly increases from 8.29 to 14.95; 2.84 to 5.07; 1 to 11.43; and 0.92 to 1.78 while treated with 1-butanol, 2-propanol, Methyl ethyl ketone, and n-hexane, respectively. Maximum oil yield to the tune of 84.36% at extraction temperature of 50 °C was attained, and maximum sludge removal of 14.95% at extraction temperature of 50 °C was achieved with 1-butanol as the optimal extracting solvent. The physicochemical properties of the recovered base oil using 1-butanol were found comparable with that of virgin lubricating oil. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Geoscience is the property of Natural Gas Geoscience and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

While the oil market‐investors sentiment (IS) has been considerably investigated, almost all studies have focused on the assumption of a constant relationship, and no attention has been given to the causality analysis in a time‐varying approach. To fill this gap, this study investigates the predictive power between IS and oil price based on a time‐varying Granger causality test. Using data over the period 1987–2020, we find evidence of significant bidirectional asymmetric time‐varying causal influences between investor sentiment and oil prices, suggesting that oil prices may predict investor sentiment and vice versa. Besides, the results suggest that bearish (bullish) investor sentiment has positive (negative) influences on oil prices during major economic and political events. In contrast, oil price exerts an influence on the sentiment which switches between positive and negative from one period to another. Further analysis shows that uncertainty related to the oil and equity markets can be a driver of the predictive power of oil prices on the bearish IS. [ABSTRACT FROM AUTHOR]

The rise in power transformer load results in degradation of the condition of the transformer oil and ultimately a deficiency in the distribution of electrical energy. This degradation can be slowed down by reconditioning transformer oil based on oil color detection. This research aims to design, test and validate a transformer oil color testing system based on color sensor and microcontroller. To obtain an accurate system, tests were carried out on selecting the types of sensors, the color of the chamber walls, and the shapes of transformer oil sample vessel used. The oil color scale of the samples was determined visually according to the ASTMD1500, 2009 standard as a benchmark. The test results showed that the TCS3200 color sensor was able to detect the color of all transformer oil samples. White chamber wall and test tube as oil sample containers were chosen to increase system accuracy. Overall, the system is able to detect the color of transformer oil, convert to the ASTMD1500, 2009 standard transformer oil color scale, determine the condition of the transformer oil and conclude the level of transformer oil degradation according to CIGRE-761, 2019. Validation results showed the system had an accuracy level of 92.65%. [ABSTRACT FROM AUTHOR]

Hydrocarbon‐based lubricants are ubiquitous in industrial applications but typically consist of complex mixtures of branched molecules that are challenging to characterize and to relate to their macroscopic properties. Consequently, lubricants are typically optimized empirically for specific applications by blending base oils with organic or inorganic additives. In this study, we report the synthesis and characterization of molecularly defined lubricants via metathesis of branched terminal olefins, followed by hydrogenation. The resulting saturated hydrocarbons are characterized by ultrahigh‐field (28.2 T) 1H and 13C NMR spectroscopies to establish their molecular structures and resolve different stereoisomers, showing the utility of state‐of‐the‐art spectroscopic tools for analyzing structures of branched alkanes. Furthermore, the molecular‐level diffusion and bulk viscosity properties compare favorably to classical synthetic lubricants based on hydrogenated polyalphaolefin (PAO) blends, establishing olefin metathesis as a selective and scalable route to high‐performance lubricant oils with defined molecular structures. [ABSTRACT FROM AUTHOR]

In this study, we model the dynamics of oil prices based on a dynamic heterogeneous agent model. Two types of agents including fundamentalists and chartists trade in the market, and the transaction costs are taken into consideration. The empirical results show that it is useful to improve forecasting performance if the model allows the agents to learn from their past performance and considers the transaction costs. Examination of the agents' dynamic weights shows that fundamentalists and chartists co-existed in the oil market with almost equal weights, and the fundamentalists dominated the market when the oil prices had large deviations from the fundamental level. [ABSTRACT FROM AUTHOR]

The effect of aging on antiwear properties of lubricants based on solutions of zinc and molybdenum dithiophosphates in oils such as I-20A, PAO-6, and VHVI-6 (viscosity grade 32 by ISO) is studied. Zinc dithiophosphate is known as an antiwear and antioxidative agent, and molybdenum dithiophosphate is a high-temperature antifriction agent. Antiwear and antiscuffing properties have been estimated by GOST 9490-75 using a four-ball testing machine. During the first test, fresh lubricants are used; then they are aged by high-temperature catalytic oxidation using technique no. 42/607 dated May 10, 1983, by VNII NP, and the second test is carried out. According to comparison of the tribological test results for fresh and aged lubricants containing the DF-11 antioxidative agent, the acid number does not increase in some cases, which is caused by the introduction of antioxidation additives in such compositions. [ABSTRACT FROM AUTHOR]

The current study systematically explores the potential of nanofluids (NFs) as dielectric media in EDM to enhance the surface integrity of Inconel 825. To achieve this objective, applying nanofluids involves ensuring uniform dispersion of nanoparticles, specifically emphasising efficient heat dissipation, thereby aligning EDM processes. This investigation focuses on utilising MWCNTs NFs, graphene NFs, and hybrid NFs (maintaining a 1:1 ratio of nanoparticles) with a hydrocarbon-based EDM oil as the base fluid. This study marks a pioneering attempt to implement these NFs in the EDM process for Inconel 825. Comprehensive characterizations of NFs have been conducted before their application in the EDM process. These have included assessments of hydrodynamic diameter, zeta potential, dynamic viscosity, thermal conductivity, and breakdown voltage. A comparative analysis has been performed between the outcomes of NFs-based EDM and conventional EDM (using EDM oil). The results show that using graphene NFs, followed by MWCNTs NFs and hybrid NFs, improves thermal conductivity and stability during the EDM process. This results in an enhanced material removal rate and better surface roughness. In-depth examinations of surface irregularities, surface microcracks, recast layer thickness, and grain orientation are carried out using scanning electron microscopy and electron backscattered diffraction. Moreover, residual stress and microhardness are systematically determined to gain further insights into surface integrity. The results indicate that the comparatively higher dispersion of graphene within base dielectric fluid provided better surface integrity for ED-machined parts. [Display omitted] • The current study systematically explores the potential of NFs as dielectric media in EDM to enhance IN825 surface integrity. • This work focuses on utilising MWCNTs NFs, graphene NFs, and hybrid NFs with a hydrocarbon-based EDM oil as the base fluid. • Comprehensive characterisations of NFs have been conducted, encompassing hydrodynamic diameter, zeta potential, etc. • In-depth examinations of surface microcracks, recast layer thickness, and grain orientation are carried out through.·Moreover, residual stress and microhardness are systematically determined to gain further insights into surface integrity. [ABSTRACT FROM AUTHOR]

This paper presents the results of thermal conductivity characterization of six high oleic soybean oil (HOSO) and four high oleic canola oil (HOCO)-based hybrid nanofluids formulated with four types of nanoparticles (Graphene nanoplatelet (xGnP), TiO2, MoS2, and Al2O3) at nanoparticles wt% concentration from 1 % to 7 % in 1 % increment using the two-step method for use in MQL machining of difficult-to-cut metals. Thermal conductivity of the formulated hybrid nanofluids were measured using Thermtest Transient Hot Wire Liquid Thermal Conductivity Meter at temperatures from 25 °C to 75 °C in increment of 10 °C. Obtained results showed that thermal conductivity of all nanofluids decreases linearly with temperature, while the thermal conductivity enhancement increases nonlinearly with increase in wt% concentration, following second order polynomial. At 7-wt% nanoparticle concentration, hybrid nanofluids xGnP-TiO2/HOSO gave the highest thermal conductivity enhancement (109.73 % and 103.31 % at 25 and 75 °C) followed by xGnP-TiO2/HOCO (101.36 % and 97.52 % at 25 °C and 75 °C), xGnP-MoS2/HOCO (101.36 % and 97.52 % at 25 °C and 75 °C), xGnP-MoS2/HOSO (96.3 % and 96.89 % at 25 °C and 75 °C), xGnP-Al2O3/HOCO (91.62 % and 83.23 % at 25 °C and 75 °C), xGnP-Al2O3/HOSO (91.25 % and 83.23 % at 25 °C and 75 °C). xGnP hybrid nanofluids are recommended for MQL machining. TiO2–MoS2/HOSO, TiO2–MoS2/HOCO, MoS2–Al2O3/HOSO, TiO2–Al2O3/HOSO hybrid nanofluids gave the lowest thermal conductivities and are not recommended as base fluids due to their insignificant thermal conductivity enhancement. Thermal conductivity of the hybrid nanofluids is lower than that of mono-nanofluids, but there are other inherent properties that could be beneficial. [ABSTRACT FROM AUTHOR]

Copyright of China Plastics / Zhongguo Suliao is the property of Journal Office of CHINA PLASTICS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Steam-Assisted Gravity Drainage (SAGD) method is recognized as one of the most effective methods for the recovery of heavy oil and natural bitumen. This technology has received several modifications throughout its history designed to improve it. One of the promising modifications is the Single Well-SAGD (SW-SAGD), which allows significantly reducing the CAPEX for drilling a well. However, this method has several disadvantages such as steam breakthrough into the production part and the uneven development of the steam chamber along the well. This article presents the concept of a Single-Well Cyclic SAGD (SWCSAGD), which allows preventing the breakthrough of the injected steam into the production section and the uniform development of the steam chamber along the well. The comparison analysis of the developed modification of SWC-SAGD was carried out using the classical method of 3D hydrodynamic modeling of both options using the example of one of the fields of the Republic of Kazakhstan. The results of the work show the efficiency of the proposed technology in terms of field oil total production. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this study was the evaluation of the production of base oils for lubricants of biological origin using vegetable and used frying oils as feedstock. The production method was based on a two-stage transesterification process. Initially, fatty acid methyl esters were obtained via methanolysis (first stage), and they were used as feedstock for bio-lubricants production by a second-stage transesterification process with the proper long-chain polyols. The produced oleochemical esters were evaluated based on their flow properties and their oxidation stability, as well as their capability of being renewable substitutes for conventional base oils, such as SN-150 and SN-500 mineral oils. The evaluation showed the remarkable physicochemical properties of these bio-lubricants, such as the viscosity, the viscosity index, and the pour, cloud and flash points, which, in combination with their high biodegradability and non-corrosive behavior, make these bio-lubricants ideal for use in special applications of non-recoverable lubrication or of high risk but low heat load and oxidative potential. This is because the oxidation stability of these bio-lubricants is not comparable to that shown by the used mineral oils and therefore they cannot totally substitute for these mineral oils. The reduced oxidation stability can be overcome by blending the bio-lubricants with mineral base oils at proper blending ratios. [ABSTRACT FROM AUTHOR]

Spherical nano-MoS2 (S-MoS2) has excellent lubricating properties and potential application value in engine oil additives. Engine soot can enter the engine oil, so the tribological interaction between S-MoS2 and diesel combustion soot (DCS) should be investigated. In this study, DCS was used to simulate engine soot. The interaction was investigated in dioctyl sebacate (DOS), and the interaction mechanism was full characterized. Results showed that S-MoS2 and DCS had obvious antagonism effects on lubrication. The 0.5% S-MoS2 exhibited good lubricating properties in DOS, which could reduce friction by ∼22% and wear by ∼54%. However, after 0.5% S-MoS2 was added to the 0.5% DCS contaminated DOS, the lubrication performance was not improved and was even worse than that without S-MoS2. When S-MoS2 was added for DOS lubrication, a tribofilm containing MoS2 formed on the friction surface, but simultaneously adding 0.5% DCS resulted in the disappearance of the MoS2 tribofilm. Moreover, under the action of friction heat, DCS and S-MoS2 could form hard MoxCy, thereby increasing abrasive wear. Finally, a preliminary deantagonism method was provided. After 2.0% zinc isooctyl dithiophosphate was added to the above antagonistic system, the friction coefficient did not show visible changes, but the wear recovered to a level close to that when only S-MoS2 was added. The antiantagonism method is not very satisfactory and some more efficient methods need to be further explored. [ABSTRACT FROM AUTHOR]

This article explores the potential of cellulose nanocrystals (CNCs) as a lubricant additive for isopropyl palmitate (IPP) oil to enhance its tribological performance. CNCs, derived from renewable sources, offer a sustainable and environmentally friendly alternative to traditional lubricant additives. A two-step method was used to prepare the nanolubricants, with visual control and dynamic light scattering measurements to assess their temporal stability. The viscous behavior of the nanolubricants, in terms of viscosity and viscosity index, was evaluated at different temperatures. The study assesses the effectiveness of CNC/IPP oil blends as lubricants through tribological tests, including evaluations under pure sliding and rolling–sliding conditions. Studies on worn surfaces were conducted using surface roughness analysis, Raman mapping, and XPS, and the thermal stability was examined to determine their suitability for different operating conditions. CNCs significantly reduce friction by up to 44% and improve wear resistance compared to the neat IPP base oil, presumably due to a self-repairing effect. Furthermore, an improvement of the thermal conductivity of pure IPP base oil has been revealed with increasing CNC concentration. This study enhances the understanding of cellulose nanocrystals as lubricant additives and their potential to transform traditional lubricating oils into high-performance and sustainable solutions. [ABSTRACT FROM AUTHOR]

The control of the vehicle transmission system is of great significance to driving comfort. In order to design a controller for smooth shifting and comfortable driving, a dynamic model of dual-clutch transmission is established in this paper. An optimal control strategy for clutch oil pressure based on linear quadratics is proposed, which is used to optimally control the oil pressure of two clutches in the torque stage and inertia stage. The control strategy selects the slipping work and jerk as evaluation indices of shift quality and establishes an optimization objective function. On the premise of optimizing the input torque, the relative speed difference between the engine and the sliding clutch in the inertia stage is adjusted. Through the optimal trajectory control of the wet clutch oil pressure, slipping work and jerk are reduced, thereby improving driving comfort. The simulation results show that the slipping work and jerk generated by the system during the shift stage are reduced, and the shift quality is improved. Additionally, compared with the controller using the MATLAB particle swarm optimization algorithm, the response speed of the proposed controller is faster, the slipping work and jerk are better reduced, and the shift quality is improved. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Geology & Oilfield Development in Daqing is the property of Editorial Department of Petroleum Geology & Oilfield Development in Daqing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Macroalgae-derived oils offer a sustainable and environmentally friendly alternative to conventional mineral oils and additives in lubricant formulation. Their favorable fatty acid profiles can contribute to mitigating the environmental impacts caused by using fossil-based products. This study evaluates the potential of Sargassum spp. oil, collected from the Mexican Caribbean, as a lubricity-enhancing additive in synthetic base oils. The impact of Sargassum spp. oil on viscosity and tribological performance was analyzed. The results indicated that Sargassum spp. oil has potential as an anti-wear additive since a formulation using 10% v/v Sargassum spp. oil in a synthetic lubricant (PAO6) resulted in a wear scar diameter value of 703.03 ± 15.56 µm, which is about 10% lower than PAO6 used as commercial synthetic control. Additionally, the formulation significantly enhanced the viscosity index, with a value of 169, which was notably higher than the control (137). The parameter of the coefficient of friction was significantly reduced from 0.1 to 0.08 (about 27%) when using the formulation with 10% v/v Sargassum spp. oil. These findings underline the potential of algae oils as additives in synthetic lubricants, promoting a transition towards greener products and reducing the environmental impact derived from conventional formulations of polyalphaolefins and esters. [ABSTRACT FROM AUTHOR]

Retinal detachment is an acute condition in ophthalmology that needs an immediate surgical management. The treatment requires a replacement of the vitreous with a temporary substitute, usually based on a silicone oil. A certain number of patients experience adverse events during the treatment. It seems this phenomenon is related to the formation of emulsions in the affected eye. These appear macroscopically as heterogeneities resembling small droplets with a patchy occurrence in the vitreous substitute. Their existence represents a major complication that may lead to loss of vision. The heterogeneities are transported to regions of the eye in which they cause irreversible damage. The current state of knowledge describes the phenomenon and recommends certain intervention procedures. Here, specific attention is paid to the chemical engineering aspects of the utilization of silicone oils for the treatment of the retinal detachment. It is very likely that the process of tiny droplet formation leading to the development of emulsions is substantially controlled by the hydrodynamic conditions in the eye. The complexity of this statement is examined in this review text. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Renewable lubricant base oils derived from biomass can effectively mitigate environmental challenges while exhibiting exceptional properties. Herein, we propose a novel approach for the synthesis of ester-based and alkane-based renewable lubricant base oils, achieving an impressive yield of up to 99%. This strategy involves the utilization of methyl oleate and biomass-derived aromatics through two distinct chemistries: alkylation and alkylation followed by hydrodeoxygenation (HDO). Among the various Lewis acid catalysts screened, AlCl3 demonstrated superior performance and achieved a remarkable maximum yield of 99% for the alkylation product under the optimized reaction conditions. Subsequent hydrodeoxygenation (HDO) of these alkylation products using the Ir-ReOx/SiO2 catalyst resulted in the production of alkane-based lubricant base oils, with an impressive maximum yield of 96.3%. The molecular size and branching of ester-based and alkane-based products can be finely adjusted by employing diverse aromatic compounds during the alkylation process, thereby enabling tuning of their lubricant properties. The as-synthesized base oils exhibit superior properties to petroleum-derived group III base oils and demonstrate comparable performance to synthetic ester and PAO base oils. The presented strategy for synthesizing renewable base oils offers a sustainable alternative to petroleum-derived counterparts, thereby potentially mitigating greenhouse gas emissions. [ABSTRACT FROM AUTHOR]

The world of lubricants is driven by the constant pursuit of improved performance in response of the requests of new engine generations. Engine oils play a critical role as lubricants in mitigating wear, reducing friction and ensuring optimal engine operation under diverse conditions. Modern commercial engine oils are complex formulations, comprising of a base oil, generally coming from petroleum sources, formulated with specific, important additives able to optimize the viscosity, thickening and shear stress in the operating temperature range. Such additives are produced in the thousand tons per year scale range. The most important class of additives for modern lubrication is made of organic polymers with variable architectures and topologies, generally referred as “viscosity modifiers” (VMs): they act as “moderators” of viscosity at different working temperatures. The tremendous advances in polymer science have been reflected in the realm of VMs, allowing the commercialization of products obtained by controlled polymerization techniques, and the experimentation of a broad variety of different macromolecular architectures and topologies as VMs. In this review we introduce the reader, together with the basic principles of viscosity modification and thermal‐dependent rheological response, to the fascinating chemistry towards the improvement of VMs, through optimization of macromolecular design and architecture. [ABSTRACT FROM AUTHOR]

In light of current high and volatile energy and food prices, we examine the daily dynamics of the conditional variance-covariance matrix and price discovery in European vegetable oils. We find that energy prices chiefly influence vegetable oil trends, while stock-to-use ratios significantly impact variance-covariance dynamics when considering their specific cold filter plugging point (CFPP). This technical detail robustly demonstrates interplays among vegetable oils based on economic principles of complementarity and substitutability, even amid the pandemic and the Russian-Ukrainian conflict. Moreover, both marginal distributions and volatility dependence structures relate to distinct economic fundamentals, enhancing our understanding of the market's complexity. [ABSTRACT FROM AUTHOR]

ABSTRACT ZnO nanoparticle surface‐modified by diisooctyl phosphate (P204) was prepared by liquid‐phase in situ surface modification technique with zinc acetate as the raw material, P204 as the modifier and anhydrous ethanol as the solvent. The morphology and microstructure of the P204‐ZnO nanoparticle were characterised by transmission electron microscopy, X‐ray diffraction and Fourier transform infrared spectrometry. Its thermal stability was evaluated by thermogravimetric analysis; and its tribological properties as the additive in alkylnaphthalene were evaluated with an SRV‐5 friction and wear tester in reciprocal sliding mode. The results show that the as‐prepared P204‐ZnO nanoparticle has an average particle size of about 4 nm and a P204 content of about 42% (mass fraction); and the surface modifier is grafted onto the surface of ZnO nanoparticle by physical adsorption. With a mass fraction of 0.5% in alkylnaphthalene base oil, P204‐ZnO nano‐additive can mildly reduce the friction coefficient and drastically reduce the wear rate of the steel–steel sliding pair. This is due to the formation of the composite tribofilm via the adsorption and deposition of the nano‐additive on rubbed steel surfaces as well as the tribochemical reactions of the modifier P204 yielding phosphate and of steel substrate yielding iron oxides. The as‐formed composite tribofilm with a thickness of about 20 nm, consisting of phosphate and iron oxides as the binder as well as deposited ZnO nanoparticle as the filling phase, is responsible for the excellent friction‐reducing and antiwear abilities of P204‐ZnO nano‐additive for the steel sliding contact. [ABSTRACT FROM AUTHOR]

Quinones are one of the most commonly used drugs for cancer treatment. Combinations of quinoid compounds and other oxidation inducers with flaxseed oil (FO), which is rich in omega‐3 alpha‐linolenic acid, show promise for improving the efficacy of antitumor drugs. Effects of benzo‐, naphtho‐, and anthraquinones, as well as metronidazole and a number of nitro‐1,2,4‐triazoles on the oxidative stability of FO, were studied. To this end, kinetic curves were obtained showing the accumulation of hydroperoxides in FO during storage at 37°C with free access to atmospheric oxygen. The calculated oxidation induction period demonstrates that the majority of the tested quinones intensify the oxidation of FO. Pro‐oxidant activity is maximum for 1,4‐benzoquinone and significantly decreases (p < 0.05) when various substituents are introduced into its ring. A noticeable increase in the concentration of hydroperoxides and the rate of oxidation at the initial stage of the oxidation process is characteristic for 1,4‐benzoquinone and its derivatives. Additives of 1,4‐naphthoquinone and 2‐hydroxy‐1,4‐naphthoquinone (lawsone) do not affect the oxidative stability of FO, while 5‐hydroxy‐1,4‐naphthoquinone (juglone) and 4,6‐di‐tert‐butyl‐1,2‐benzoquinone effectively inhibit the oxidation of FO. The oxidation of FO lipids is accelerated by all investigated nitroazoles; however, 1‐methyl‐3,5‐dinitro‐1,2,4‐triazole has the highest pro‐oxidant activity. Practical Applications: The results of this study may be useful in the development of new methods of antitumor therapy using omega‐3 polyunsaturated substrates in combination with quinoid and nitrotriazole cytostatics. The data obtained can also be used in the development of oxidation‐stable foods based on flaxseed oil, as well as in the production of resins, drying oils, varnishes, paints, and other materials. [ABSTRACT FROM AUTHOR]

In the realm of lubrication, nanoparticles play a pivotal role in enhancing the tribological efficacy of lubricating oils. Unveiling a critical need, the research underscores the necessity for a predictive model capable of anticipating these performance characteristics. This research endeavors to fill this gap by introducing an artificial neural network (ANN) tailored specifically for predicting the behavior of nanolubricants. The optimized neural network structure, at 5 × 8 × 2, attains a remarkable minimum mean square error of 0.00046667, with R-values hovering at impressive proximity to unity (0.99828). During the confirmation phase, the neural network's predictions demonstrate a deviation of 7.51% (negative) and 2.87% (negative) for COF, alongside 0.50% and 1.80% for WSD, further affirming its predictive capacity in assessing lubricant performance characteristics. [ABSTRACT FROM AUTHOR]

The Tesla-type pulsed power generator based on transformer oil is limited by volume and weight, which affects its suitability for mobile platforms. In this paper, a double-width pulse forming line (PFL) based on high-energy-density liquid medium Midel 7131 was designed, and a compact, high-repetitive pulsed power generator was developed. The structural and electrical parameters of the PFL with an outer diameter of 1000 mm were optimized to achieve the highest output power with a fixed load impedance of 60 Ω. This generator employed a double-width forming line, which has an output pulse width of four times of the electrical length of its external line, significantly increasing the output pulse width and making the system more compact. The generator could be finally enveloped with a size of 4 × 1.5 × 1.5 m3 and a weight of 4.7 tons. The experiment showed that the generator could operate reliably under the conditions of 15-GW peak power, 50-ns pulse width, 50-Hz repetition rate, and <1% voltage jitter. The X-band relatively backward wave oscillator driven by this generator yielded a favorable microwave, which demonstrated the high-power driving capability of the generator. [ABSTRACT FROM AUTHOR]

The tribological properties of lubricants containing the same additives often vary with varying hardness and composition of the frictional parts. This means that, in terms of the effectiveness of lubricant additives, most of current researches using GCr15 steel to assemble the frictional pair could not be directly cited by the moving parts made of other materials. Aiming at verifying if RNS‐1A‐PIBSA (referring to amino‐functionalized silica nanoparticle [RNS‐1A] after secondary surface‐capping by polyisobutylene succinic anhydride [PIBSA]) is suitable for multiple frictional parts made of different materials with varying hardness and composition, herein we investigate its applicability an additive in poly‐alpha‐olefin 6 (PAO6) base oil to three types of sliding pairs constructed from GCr15 steel, #45 steel, and ductile iron with much different hardness and composition by SRV‐5. A series of analyses of worn surface morphology and composition demonstrate that, independent of the composition and hardness of the frictional pairs, RNS‐1A‐PIBSA added in PAO6 base oil can form silica deposition film on the rubbed surfaces of the three kinds of sliding pairs, thereby effectively reducing friction and wear. Besides, we also examine the effect of RNS‐1A‐PIBSA on the thermal stability of the PAO6 base oil, and found the nano‐additive RNS‐1A‐PIBSA can delay the thermal decomposition of PAO6 base oil to some extent, which is favourable for its application in lubrication engineering. [ABSTRACT FROM AUTHOR]

Scientific and effective classification of gas wells is conducive to mastering production characteristics of wells and establishing reasonable production measures. Therefore, based on the similarity of time series, and in conjunction with spectral clustering, this paper proposes a new classification model for tight sandstone gas wells: the KF-SDTW-Spectral model. The research results show that the 61 tight sandstone gas wells can be divided into clusters using different classification indicators: two clusters based on monthly gas production, three clusters based on monthly water production, and three clusters based on oil pressure. The model exhibits high clustering quality, surpassing traditional clustering methods. By using this model, the production characteristics of high-yield and low-yield wells are analyzed and corresponding production measures are proposed. This paper provides a new approach on the classification of tight sandstone gas wells, offering valuable guidance for the formulation of production measures in the gas field. [ABSTRACT FROM AUTHOR]

The transition to electric vehicles (EVs) has introduced new challenges in lubrication, demanding innovative solutions to ensure consistent performance. One promising approach is the use of nanoparticle additives, which have the potential to improve lubrication performance significantly. However, achieving a stable suspension of these nanoparticles in lubricating oils remains a critical challenge, as suspension stability is essential for maintaining consistent performance and maximizing the benefits of these advanced additives. In this study, carbon nanoparticles (CNPs) were modified with dodecylamine (DDA) to achieve stable suspension in nonpolar fluids. The successful functionalization was confirmed by the FTIR results, which showed characteristic peaks of various bonding. The suspension stability tests demonstrated that DDA-CNPs remained suspended for over 60 days in the Polyalphaolefin (PAO) oil, whereas unmodified CNPs were sedimented within 3–7 days. The rheological behavior was measured under different shear rates and temperatures. Viscosity measurements indicated that DDA-CNPs maintained a lower value compared to base PAO. The lubricants' friction coefficient (COF) was also determined under various speeds and loads. The addition of DDA-CNPs at a concentration of 0.05 wt.% resulted in a significant reduction in COF, with values decreasing by 26% compared to base PAO oil under a load of 1 N. Additionally, the COF for DDA-CNPs was consistently lower than that of PAO, with reductions ranging from 15% to 18% across all tested speeds. The Stribeck curve further highlighted the improved performance of DDA-CNPs across boundary, mixed, and hydrodynamic lubrication regimes. These findings suggest that DDA-CNPs significantly improve the lubrication performance of PAO oil, making them suitable for advanced lubrication applications in automotive and industrial systems. [ABSTRACT FROM AUTHOR]

Deep eutectic solvents (DESs) are acknowledged as a novel class of functional liquid. DESs share similar physical properties with ionic liquids (ILs) and have the potential to be a novel class of lubricants. In this study, two DESs, namely tetrabutylammonium chloride-decanoic acid DES (C4-DES) and methyl tricaprylmethylammonium chloride-decanoic acid DES (C8-DES), were synthesized, and their physico-chemical properties and tribological performances were evaluated. Post-analysis of the rubbing surfaces used multiple techniques to gain insights into the lubrication mechanisms. Results show that the coefficient of friction (COF) and wear were reduced by approximately 29% and 91% for the C4-DES, and 36% and 94% for the C8-DES, compared to an ester base oil. The friction reduction behavior of the DESs is attributed to the monolayer adsorption of the polar group in the decanoic acid (DEAC), whose effectiveness is affected by the component of the ammonium salts in the DESs and the operating temperatures. In addition to the adsorbed film, worn surface analysis revealed that an ultra-thin tribochemical film with a thickness of 3–7 nm was formed on the surfaces lubricated with the C8-DES. The composition of the film was studied, and the lubrication mechanisms of the two DESs were discussed. [ABSTRACT FROM AUTHOR]

Lubricating oils play a crucial role in modern industrial production, mechanical manufacturing, aerospace, and other fields. This paper provides a review and summary of the entire workflow for molecular simulations of lubricating oils, from molecular modeling, especially the molecular representation of base oils, to simulation calculation methods and result analysis. The application prospects and values of the relevant simulation techniques are discussed in detail. The simulation methods, force fields, and software involved in the modeling and simulation process are also introduced, aiming to provide guidance and insights for more rigorous, rational, and accurate lubricant molecular simulations, so as to accelerate the modification and development of new high-quality lubricants. [ABSTRACT FROM AUTHOR]

In order to ensure the accuracy of oilfield development dynamic data, the author starts from analyzing the characteristics of development dynamic data, and conducts in-depth research on the characteristics of development dynamic data, the algorithm set for accuracy detection of development dynamic data, and comprehensive analysis methods. Firstly, in response to the spatiotemporal heterogeneity in developing dynamic data, combined with the design concept of a multi detector combination algorithm based on spatiotemporal mixed patterns, the accuracy detection algorithm is evaluated and selected. Based on this, the author proposes a development dynamic data accuracy detection method that considers the influence of multiple factors (FAGTN); Secondly, ARIMA, MGLN, STGCN, and FAGTN algorithms were selected as the algorithm sets for developing dynamic data accuracy detection, in order to complete the data accuracy detection based on monthly oil well data as the research object; Then, a combined weighting based analysis method was proposed to comprehensively analyze the accuracy detection results of dynamic data development, and the results showed: The dynamic data accuracy detection method based on ARIMA has the worst performance, with detection accuracy below 70% in different detection attributes, which is relatively not high enough; The development of dynamic data accuracy detection method based on MGLN achieved an accuracy rate of 80.53% when detecting sleeve pressure, but the accuracy rate did not reach 80% when detecting oil pressure, dynamic liquid level, monthly oil and water production, and the detection effect was relatively unstable; The accuracy of developing dynamic data accuracy detection methods based on STGCN fluctuates around 80%; Realize comprehensive evaluation of detection results; Finally, the experiment and evaluation of the comprehensive detection method for developing dynamic data accuracy were completed using real sample data. [ABSTRACT FROM AUTHOR]

Compared with conventional plant oils, diacylglycerol (DAG)‐based fats exhibit a higher melting point and could serve as a solid base oil for preparing specialty fats. In this study, different chain length DAG‐based solid fats were prepared, and the influences of acyl groups on the physical property, crystal microstructure, and crystallization kinetics of the binary solid fat phase were explored. The slipping melting point (SMP) of obtained medium chain‐DAG (MCD‐fats), medium‐long chain‐DAG (MLCD‐fats), and long chain‐DAG (LCD‐fats) fats were 35.67, 40.70, and 52.30°C, and their original β′ crystal content were 46.3%, 56.1%, and 66.9%, respectively. The solid fat content (SFC) profiles and crystallization properties were significantly affected as the fatty acid chain length and acylglycerols compositions changes. The microstructure of crystal in DAG‐fats got denser slowly during storage. DAG can delay the translation of crystal form and stabilize β′ crystal form, which is related to their three‐dimensional crystalline network changes. The hardness of MCD‐fats and LCD‐fats were higher than that of MLCD‐fats because of the acylglycerol compositions as well as fat crystals in DAG‐fats. Applying high melting point DAG as a novel base stock has an immense potential value in the production of specialty fats with low saturated fat, high stability, and decent operability. [ABSTRACT FROM AUTHOR]

AbstractThe experimental study assessed the impact of choline chloride cation-based ionic liquid (IL), on the dispersion stability and wear characteristics of copper (II) oxide (CuO) nanoparticles (NPs) in synthetic base oil (PAO 10). CuO NPs, averaging 50 nm in size, underwent surface modification using varying concentrations of the IL (0.25%, 0.5%, 0.75%, and 1% by weight). The formulations were subjected to sliding wear tests to evaluate their wear behavior. Analysis of the worn surfaces utilized scanning electron microscopy, energy-dispersive x-ray spectroscopy, and atomic force microscopy. The results indicated that the combination of 0.75% IL and 1% CuO NPs provided optimal dispersion and exhibited effective surface mending, enhancing wear protection by 21.1% than that of PAO 10. The formulation containing 1% IL and 1% CuO NPs demonstrated the highest load carrying capacity among all tested compositions. In terms of wear behavior, the nanolubricant formulations with 0.75% and 1% IL outperformed the lubricant formulation containing 1 wt% of the commercial antiwear additive Zinc dialkyldithiophosphates (ZDDP). [ABSTRACT FROM AUTHOR]

Oleogels are semi-solid materials that consist primarily of liquid oil immobilized in a network of organized structural molecules, which provide stability and maintain the oil in the desired shape. Due to their structure, oleogels can stabilize large amounts of liquid, making them excellent carriers for active substances, both lipophilic and hydrophilic. This study presents the synthesis methodology and investigations of olive oil-based oleogels, which are among the healthiest and most valuable vegetable fats, rich in unsaturated fatty acids and antioxidants such as vitamin E. Two types of surfactants were used: TWEEN 80, which lowers surface tension and stabilizes emulsions, and SPAN 80, which acts in oil-dominated phases. The oleogels were enriched with lidocaine, an active substance commonly used as a pain reliever and local anesthetic. This research characterized the obtained oleogels regarding their medical applications, paying particular attention to the influence of surfactant type and amount as well as the active substance on their physicochemical properties. Structural analyses were also conducted using Fourier transform infrared (FTIR) spectroscopy, alongside rheological and sorption studies, and the wettability of the materials was evaluated. The stability of the obtained oleogels was verified using the MultiScan MS20 system, allowing for an assessment of their potential suitability for long-term pharmaceutical applications. The results indicated that SPAN-stabilized oleogels exhibited better stability and favorable mechanical properties, making them promising candidates for medical applications, particularly in pain relief formulations. [ABSTRACT FROM AUTHOR]

In this paper, the effect of random permeability is considered for the real fracture reservoir, hence a stochastic dual-porosity-Navier-Stokes model with random permeability is proposed to simulate shale oil problem based on superhydrophobic material modification. Finite element method and Monte Carlo method are used to deal with discrete physical space and probability space, respectively. The decoupled finite element method with backward-Euler temporal discretization is presented, which allows the coupling problem to be divided into three subproblems in a non-iterative manner. Furthermore, the stability analysis and error estimation of the corresponding partition scheme are given. 2D/3D numerical experiments verify the validity of the theoretical analysis and prove the reliability and applicability of the scheme. [ABSTRACT FROM AUTHOR]

The aim of this study is to evaluate the lubricating performance of various base oils in a hydrogen-enriched environment. Experiments were conducted wherein base oils were emulsified with meticulously calibrated hydrogen concentrations, followed by a series of friction and wear measurements. Elemental analysis was performed on the worn surfaces, providing further insight into the wear mechanism. The findings of this study highlight the pronounced effect of hydrogen on the lubrication of pure water emulsions of Class IV 4 base oils, with the Class V 5-1 base oils showing optimal lubricating performance in hydrogen-enriched conditions. SEM images at high magnification scanning revealed the presence of a protective friction film on the surfaces of the wear scars in each sample. X-ray photoelectron spectroscopy (XPS) identified traces of metal sulfide within the friction film, which may play a role in reducing friction. The formation of this friction film is likely a contributing factor to the enhanced lubricating performance of the base oil. These findings contribute a substantial foundation for the development of standards for evaluating the performance of hydrogen internal combustion engine oils. [Display omitted] • Study on water emulsification of oil in hydrogen internal combustion engine. • The participation of hydrogen plays an anti-wear and anti-friction effect. • The lubrication effect of hydrogen on class IV emulsion is significantly improved. • The lubrication effect of class V emulsion is the best in hydrogen environment. • The participation of hydrogen contributes to the formation of metal sulfide films. [ABSTRACT FROM AUTHOR]