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China shale oil can be classified as interlayer shale oil (in sandstone, carbonate, and diamictite) and genuine shale oil. Considering the characteristics and strong heterogeneity of continental shales, it is recommended to evaluate the interlayer shale oil resources using the elemental volume method based on pore volume, and the genuine shale oil resources using the elemental weight method based on oil content. Four key parameters for genuine shale oil resource evaluation (i.e., S1, TOC, Ro, and shale thickness) and three key parameters for interlayer shale oil resource evaluation (i.e., interlayer thickness, porosity, and oil saturation) are determined, and the lower limits of parameters are defined accordingly. The evaluation results show that the geological resources of genuine shale oil in Qing-1 member of Songliao Basin are 52.23 × 108 t; the geological resources of shale oil in Chang-73 sub-member of Ordos Basin are 66.80 × 108 t, including 27.73 × 108 t interlayer shale oil and 39.07 × 108 t genuine shale oil; the geological resources of shale oil in Lucaogou Formation of Junggar Basin are 15.62 × 108 t, including 11.99 × 108 t interlayer shale oil and 3.63 × 108 t genuine shale oil. This study provides a reference for exploration decision of shale oil in China. [ABSTRACT FROM AUTHOR]

Camellia oil is a high-quality edible vegetable oil with a variety of physiologic functions. To accurately identify the camellia oil, the qualitative and quantitative determination of fatty acids in camellia oil was conducted by gas chromatography. The fatty acids in camellia oil were oleic acid, linoleic acid, palmitic acid, stearic acid and linolenic acid. Among them, the proportion of monounsaturated fatty acid oleic acid was 77.56–82.60%. Based on the gas-chromatography, effective fingerprints were established for 13 camellia-oil samples grown in Zhejiang Province of China. The results of similarity analysis showed that camellia oil grown in this area had a high similarity, the similarity was as high as 0.998. Combining fingerprint analysis with chemometrics, the classification of camellia oil samples based on the difference of fatty acid content could be achieved using the shortest distance method in hierarchical cluster analysis. The key fatty acids, oleic and linolenic acid, were identified through principal component analysis. Indeed, camellia oil from various production areas within a 200-km radius in Zhejiang Province, China, could be distinguished based on the two main fatty acids. The quality of the 13 types of camellia-oil samples was assessed and categorized through scoring, ranging from − 1.69 to 3.72. In this study, gas chromatography fingerprinting technique was combined with chemometrics which allowed to identify camellia oil samples quality and distinguish the samples according to their geographic origin. [ABSTRACT FROM AUTHOR]

Tailoring of organometallics structure toward desirable properties continues to be both fascinating and challenging in the field of materials science. Herein, a novel ferrocene derivative with long straight‐chain alkane mono‐substituent is synthesized and used as multifunctional organometallic additive in the base oil. This ferrocene‐based organometallic compound (MFc) is synthesized via the Friedel‐Crafts acylation of ferrocene with myristyl chloride, followed by reduction with sodium borohydride. The chemical structure, crystallizability, surface morphology, and the thermal properties of the as‐synthesized compound are systematically characterized. As the iron‐containing standard substance, the MFc was preferable dissolve in lubricating oil with the iron element content as high as 2*105 ppm. Resultantly, the MFc/oil solutions exhibited excellent stability even after high‐speed centrifugal treatment, long‐term storage up to 3 months, and ultra‐low temperature treatment at −40°C for 24 h. Moreover, the MFc as a functional lubricant additive could reduce the average wear scar diameter, wear volume, and coefficient of friction with 40%, 73%, and 18%, respectively, as compared to the corresponding pure base oil. This synthetic strategy provides a novel perspective for the design of functional organometallics, and the as‐synthesized novel ferrocene derivative may find a wide range of advanced potential applications in analytical chemistry, tribology, and interfacial science. [ABSTRACT FROM AUTHOR]

This study analysed and discussed the friction and wear properties, as well as the interface evolution behaviour of polycrystalline diamond compact (PDC) under various base oils, through conducting friction experiments on PDC/Si3N4 with different base oils. The friction and lubrication mechanism of PDC under different base oils were examined using scanning electron microscopy (SEM), x‐ray energy dispersive spectrometry (EDS), three‐dimensional white light interferometry, and Raman spectroscopy. The results of the study demonstrated that PDC exhibited the best friction and wear performance when lubricated with synthetic oil PAO, followed by castor oil. The inferior performance of paraffin oil can be attributed to its low viscosity, resulting in a lower presence of ions capable of passivating the carbon dangling bond. Consequently, paraffin oil displayed inadequate oxidation stability and increased susceptibility to oil film destruction, ultimately leading to suboptimal friction and wear characteristics. Overall, this study provides valuable insights for industrial applications, aiding in the selection of appropriate base oils as cutting fluids for PDC cutting tools and enhancing the friction and wear properties of PDC. [ABSTRACT FROM AUTHOR]

Nowadays, researches on the use of alkali metal salts as friction‐reducing and anti‐wear oil additives are continuing. In this study, the tribological effects of heavy metal containing MoS2 and alkali metal salt CaF2 additives on pure engine oil (20W50) were investigated using block‐on‐ring tester configured as surface contact geometry. The tests were performed at various contact loads, revolutions, and additive ratios. The crystal structure of the additives and their effects on surface quality and surface roughness analysed by x‐ray crystallography, scanning electron microscope and profilometry. Moreover, Energy dispersive spectrometry was used for element detection on worn surfaces. Results indicated that additives of MoS2 and CaF2 can reduce the friction, increase the capacity of load‐carrying and the wear resistance of surfaces. The additives improved the operation of the base oil in boundary lubrication zone by increasing the tribofilm forming effect. It was observed that the CaF2 additive exhibited more stable friction behaviour, while the MoS2 additive has better protective effects against scratches on the block surface. [ABSTRACT FROM AUTHOR]

Background: Mentha longifolia L. is a perennial plant belonging to the Lamiaceae family that has a wide distribution in the world. M. longifolia has many applications in the food and pharmaceutical industries due to its terpenoid and phenolic compounds. The phytochemical profile and biological activity of plants are affected by their genetics and habitat conditions. In the present study, the content, constituents and antifungal activity of the essential oil extracted from 20 accessions of M. longifolia collected from different regions of Iran and Iraq countries were evaluated. Results: The essential oil content of the accessions varied between 1.54 ± 0.09% (in the Divandarreh accession) to 5.49 ± 0.12% (in the Khabat accession). Twenty-seven compounds were identified in the essential oils of the studied accessions, which accounted for 85.5-99.61% of the essential oil. The type and amount of dominant compounds in the essential oil were different depending on the accession. Cluster analysis of accessions based on essential oil compounds grouped them into three clusters. The first cluster included Baziyan, Boukan, Sarouchavah, Taghtagh, Darbandikhan, Isiveh and Harir. The second cluster included Khabat, Kounamasi, Soni and Mahabad, and other accessions were included in the third cluster. Significant correlations were observed between the essential oil content and components with the climatic and soil conditions of the habitats. The M. longifolia essential oil indicated antifungal activity against Fusarium solani in both methods used. In all studied accessions, the fumigation method compared to the contact method was more able to control mycelia growth. In both methods, the inhibition percentage of essential oil on mycelia growth increased with an increase in essential oil concentration. Significant correlations were found between the essential oil components and the inhibition percentage of mycelium growth. Conclusion: The studied M. longifolia accessions showed significant differences in terms of the essential oil content and components. Differences in phytochemical profile of accessions can be due to their genetic or habitat conditions. The distance of the accessions in the cluster was not in accordance with their geographical distance, which indicates the more important role of genetic factors compared to habitat conditions in separating accessions. The antifungal activity of essential oils was strongly influenced by the essential oil quality and concentration, as well as the application method. Determining and introducing the elite accession in this study can be different depending on the breeder's aims, such as essential oil content, desired chemical composition, or antifungal activity. [ABSTRACT FROM AUTHOR]

The antiwear properties of tribofilms formed on steel surfaces lubricated with various multi-component lubricants were investigated at an elevated temperature and under load-speed conditions conducive to sliding in the boundary lubrication regime. The lubricants contained base oil, reduced-level (secondary) zinc dialkyl dithiophosphate (ZDDP), and nitrogenous dispersant. The wear resistance of the tribofilms produced from different oil blends was evaluated in the context of the rate of change in the sliding track volume (wear rate for material loss) and the load-bearing capacity, chemical composition, and thickness of the tribofilms. Surface profilometry and scanning electron microscopy were used to quantify the wear performance and detect the prevailing wear mechanisms, whereas X-ray photoelectron spectroscopy elucidated the chemical composition and thickness of the tribofilms. The oil blends without ZDDP did not produce tribofilms with adequate antiwear properties, whereas the oil blends containing ZDDP and dispersant generated tribofilms with antiwear characteristics comparable to those of tribofilms produced from blends with a higher ZDDP content. Although dispersants can suspend oil contaminants and preserve the cleanness of the sliding surfaces, it was found that they can also reduce the antiwear efficacy of ZDDP. This was attributed to an additive-dispersant antagonistic behavior for surface adsorption sites affecting tribofilm chemistry and mechanical properties. Among the blends containing a mixture of ZDDP and dispersant, the best antiwear properties were demonstrated by the tribofilm produced from the blend consisting of base oil, 0.05 wt% ZDDP, and a bis-succinimide dispersant treated with ethylene carbonate. The findings of this investigation demonstrate the potential of multi-component lubricants with reduced-content ZDDP and nitrogen-based dispersant to form effective antiwear tribofilms. [ABSTRACT FROM AUTHOR]

Electric vehicles (EVs) have emerged as a technology that can replace internal combustion vehicles and reduce greenhouse gas emissions. Therefore, it is necessary to develop novel low-viscosity lubricants that can serve as potential transmission fluids for electric vehicles. Thus, this work analyzes the influence of both SiO2 and SiO2-SA (coated with stearic acid) nanomaterials on the tribological behavior of a paraffinic base oil with an ISO VG viscosity grade of 32 and a 133 viscosity index. A traditional two-step process through ultrasonic agitation was utilized to formulate eight nanolubricants of paraffinic oil + SiO2 and paraffinic base oil + SiO2-SA with nanopowder mass concentrations ranging from 0.15 wt% to 0.60 wt%. Visual control was utilized to investigate the stability of the nanolubricants. An experimental study of different properties (viscosity, viscosity index, density, friction coefficient, and wear) was performed. Friction analyses were carried out in pure sliding contacts at 393.15 K, and a 3D optical profilometer was used to quantify the wear. The friction results showed that, for the SiO2-SA nanolubricants, the friction coefficients were much lower than those obtained with the neat paraffinic base oil. The optimal nanoparticle mass concentration was 0.60 wt% SiO2-SA, with which the friction coefficient decreased by around 43%. Regarding wear, the greatest decreases in width, depth, and area were also found with the addition of 0.60 wt% SiO2-SA; thus, reductions of 21, 22, and 54% were obtained, respectively, compared with the neat paraffinic base oil. [ABSTRACT FROM AUTHOR]

Accurately determining the solubility of ethane in oil‐based mud is crucial for assessing the severity of gas kicks and implementing appropriate well control procedures. The key factors influencing the solubility of ethane gas in oil‐based drilling fluids include the content of base oil, pressure, temperature, and the viscosity of the drilling fluid. This study aims to test the solubility of high‐purity ethane in oil‐based mud under simulated downhole conditions in a 5000 m deep well. The test covers a temperature range of 40–140°C and a partial pressure range of 0.17–5.92 MPa. The effects of temperature, pressure, base oil content, and drilling fluid viscosity on the solubility of ethane are analyzed using various experimental data processing methods. The results show that the variation in ethane solubility with pressure and temperature is nearly linear within the specified ranges. Furthermore, the impact of pressure (1.24–2.78%/MPa) on solubility is approximately 50 times greater than that of temperature (−0.013 to −0.049%/°C) in oil‐based drilling mud. Additionally, ethane's solubility decreases as the drilling fluid's viscosity increases. The ethane solubility in 80% and 90% oil‐based muds is roughly 1.6 times and 2.0 times higher than in 70% oil‐based mud under the same testing conditions. Models for predicting ethane solubility have been developed using screening procedures and statistical regression. These models can be incorporated into gas–liquid flow models to analyze flow behavior during gas kicks. [ABSTRACT FROM AUTHOR]

The electronic nose is a non-invasive technology suitable for the analysis of edible oils. One of the practical applications in the olive oil industry is the classification of virgin oils based on their sensory characteristics. Notwithstanding that this technology, at this stage, cannot realistically replace the currently used methods, it is fruitful for a preliminary analysis of the oil quality. This work makes use of this technology to develop a methodology for the detection of the threshold by which an extra-virgin olive oil (EVOO) drops into the virgin olive oil (VOO) category. With this aim, two features were studied: the level of fruitiness level and the type of defect. The results showed a greater influence of the level of fruitiness than the type of defect in the determination of the detection threshold. Furthermore, three of the sensors (S2, S7 and S9) of the commercial e-nose PEN3 were identified as the most discriminating in the classification between EVOO and VOO oils. [ABSTRACT FROM AUTHOR]

Oil shale, as a vast potential resource, is considered an important alternative energy source, and its effective development and economic utilization are of significant importance in alleviating the contradiction between energy supply and demand. Presently, the in situ conversion technology for oil shale has gained significant global attention, with numerous extraction methods undergoing active research and development. One of these methods is the in situ conversion of oil shale based on the hydration reaction of calcium-oxide-based composite material (CaO-CM). This approach harnesses the heat produced by the reaction between CaO-CM and water as a heat source for the pyrolysis of oil shale. This paper conducted experiments to assess the feasibility of temperature associated with this method. The feasibility study mainly includes two aspects: First, it is necessary to investigate whether the temperature generated by the hydration reaction of CaO-CM can meet the temperature requirements for the pyrolysis of oil shale. Through pyrolysis experiments of Xinjiang oil shale, the minimum temperature required for oil shale pyrolysis was determined to be 330 °C. High-temperature and high-pressure reaction vessels were employed to explore the temperature generated by the hydration reaction of CaO-CM. The results show that with the increase in environment pressure, environment temperature, and reaction mass, the maximum temperature generated by the hydration reaction of CaO-CM also increases (reach 455.5 °C), meeting the temperature requirements for the pyrolysis of oil shale. Second, the study evaluates whether the hydration reaction of CaO-CM can induce pyrolysis hydrocarbons of the oil shale. Through the pyrolysis experiments of oil shale based on the hydration reaction of CaO-CM, the changes in the content of pyrolysis hydrocarbons (S2) in oil shale before and after pyrolysis are measured. The results show that under 10 MPa pressure, the content of pyrolysis hydrocarbons in the oil shale decreased from 40.96 mg/g to 0.08 mg/g after pyrolysis. This confirms the feasibility of the temperature conditions for the in situ conversion of oil shale based on the hydration reaction of CaO-CM. [ABSTRACT FROM AUTHOR]

The complex lithology, frequent interbedding and strong heterogeneity of the shale oil reservoir in Lucaogou Formation of the Middle Permian in Jimsar Sag lead to the complexity of litho‐electric parameters and the low accuracy of conventional reservoir saturation evaluation methods. Therefore, in this paper, automatic lithologic identification was firstly performed with the optimization inversion method of mineral components and K‐means clustering algorithm, and then, litho‐electric experiments were carried out to determine the litho‐electric parameters of different lithologies. Furthermore, the shale oil reservoir saturation calculation models of different lithologies were optimized and determined. Then, a composite water saturation model (Composite‐SW) based on complex lithology identification was constructed. Finally, the model was verified and analysed with the experimental results of water saturation. The coefficient of correlation between the calculation results of the Composite‐SW model and the core experiment results reached.88, indicating that the model was much better than conventional models. The model can be widely applied in logging evaluation of the continental mixed shale oil reservoir in the study area. The study provides a new idea for oil saturation evaluation of continental shale oil reservoirs and is significant for evaluating other types of shale oil reservoirs. [ABSTRACT FROM AUTHOR]

Summary: D‐limonene is an important flavouring ingredient with a wide range of applications. However, its high volatility and low stability have severely impacted its application in the food industry. To address these limitations, temperature‐flavour release control system is expected to be established to reduce the loss of D‐limonene during processing and storage, as well as to control its release by temperature. The aim of the current study is to construct an oleogel system to encapsulate D‐limonene using carnauba wax as a gelling agent and palm oils (POs) as the base oil. POs with 24 °C, 38 °C, 42 °C, 48 °C, and 52 °C melting points were selected to systematically investigate the effects of the base oil melting point on the crystal morphology, interactions, physicochemical properties, microstructure, and D‐limonene release of the oleogels. The enthalpy of melting, enthalpy of crystallisation, hardness, stickiness, and gel strength increased in oleogels prepared using POs with a higher melting point. In addition, the oil‐binding capacity (OBC) (>95%) of the oleogels increased with the base oil melting point, while the fat crystal distribution became more homogeneous and denser. Based on the influence that extraction temperature has on the concentration of released D‐limonene (a lower concentration of aroma was released from high‐melting‐point POs oleogels at low temperatures (<1.9 mg mL−1), whereas the control group released >2.5 mg mL−1), suitable POs can be selected to achieve the release or retention of the aroma. These results demonstrate that a temperature‐responsive flavour delivery system can be prepared with different PO melting points. The molecular dynamics of flavour release revealed that storage temperature and fat crystalline state impact the cumulative release rate of D‐limonene. [ABSTRACT FROM AUTHOR]

Controlling friction by light field is a low-cost, low-energy, non-polluting method. By applying ultraviolet light on the surface of photosensitive materials, the properties of the friction pairs or lubricant can be influenced, thus achieving the purpose of reducing friction. In this study, TiO2, an inorganic photosensitive material, was selected to investigate the modulating effect of light fields on friction lubrication when using polyalphaolefin (PAO) base oil as a lubricant, and the modulation law of light fields on the friction lubrication behavior was investigated under different loads (1–8 N), different speeds (20–380 mm/s), and different viscosities (10.1–108.6 mPa·s) of PAO base oil. The experimental results showed that light treatment could reduce the friction coefficient of PAO4 base oil lubrication from 0.034 to 0.016, with a reduction of 52.9% under conditions of 3 N-load and 56.5 mm/s-speed, and the best regulation effect could be achieved under the mixed lubrication condition. After TiO2 was treated with ultraviolet light, due to its photocatalytic property, PAO molecules were oxidized and adsorbed on the TiO2 surface to form an adsorption layer, which avoided the direct contact of rough peaks and thus reduced the friction coefficient. This study combines photosensitivity, photocatalysis, and friction, presenting a method to reduce the friction coefficient by applying a light field without changing the friction pairs or lubricants, which provides a new direction for friction modulation and gives new ideas for practical applications. [ABSTRACT FROM AUTHOR]

The polymeric additives prepared from renewable feedstock having multifunctional applicability attracted significant attention in the lubricant industry. The present research focuses on a comparative study of multifunctional polymeric additives MPA-1 and MPA-2 synthesized via copolymerizing the triglyceride of olive oil and a homopolymer of stearyl methacrylate, respectively, using benzoyl peroxide as a free radical initiator. The synthesized additives were characterized by routine spectroscopic techniques like FT-IR and NMR spectroscopy. In contrast, the molecular weight was determined by gel permeation chromatography (GPC), and thermal stability was analyzed by thermogravimetric analysis (TGA). The additives were also evaluated for rheological analysis using Anton Paar MCR-72 by formulating the additives into mineral base oil (N-150) in three different concentrations, viz. 0.5%, 1.0% and 1.5% w/v. The formulated lubricant was analyzed for physicochemical parameters like viscosity index and pour point by standard ASTM methods. It was observed that both the MPAs additive shows improvement in the physicochemical and rheological properties of the base oil. Thus, the polymeric additives synthesized and formulated with mineral base oil show multifunctional applications. [ABSTRACT FROM AUTHOR]

Recent developments in micro and nanoencapsulation are promising tools to encounter the different limitations of essential oil formulations, enhance their functionalities, and protect them from the external environmental conditions. This review addresses the current studies and progresses related to the development of encapsulated essential oils using different systems and carrier material types. It also focuses on the formation methods used with the subsequent physicochemical characterization of the developed particles. Moreover, this review considers the factors affecting the release of essential oils with the different physicochemical release models. The choice of the appropriate formation method as well as the carrier material types and system forms were shown to highly depend on the intended purpose of the encapsulated essential oil formulation. Micro and nanoencapsulation are used to control essential oils' release properties, enhance the various characteristics of essential oils, and allow to expand applications in different fields. This review provides the optimal conditions for micro and nanoencapsulation of essential oil formulations based on the intended end uses. [ABSTRACT FROM AUTHOR]

The diagenetic facies of tight oil reservoirs reflect the diagenetic characteristics and micro-pore structure of reservoirs, determining the formation and distribution of sweet spot zones. By establishing the correlation between diagenetic facies and logging curves, we can effectively identify the vertical variation of diagenetic facies types and predict the spatial variation of reservoir quality. However, it is still challenging work to establish the correlation between logging and diagenetic facies, and there are some problems such as low accuracy, high time consumption and high cost. To this end, we propose a lithofacies identification method for tight oil reservoirs based on hybrid intelligence using the Fuyu oil layer of the Sanzhao depression in Songliao Basin as the target area. Firstly, the geological characteristics of the selected area were analyzed, the definition and classification scheme of diagenetic facies and the dominant diagenetic facies were discussed, and the logging response characteristics of various diagenetic facies were summarized. Secondly, based on the standardization of logging curves, the logging image data set of various diagenetic facies was built, and the imbalanced data set processing was performed. Thirdly, by integrating CNN (Convolutional Neural Networks) and ViT (Visual Transformer), the C-ViTM hybrid intelligent model was constructed to identify the diagenetic facies of tight oil reservoirs. Finally, the effectiveness of the method is demonstrated through experiments with different thicknesses, accuracy and single-well identification. The experimental results show that the C-ViTM method has the best identification effect at the sample thickness of 0.5 m, with Precision of above 86%, Recall of above 90% and F1 score of above 89%. The calculation result of the Jaccard index in the identification of a single well was 0.79, and the diagenetic facies of tight reservoirs can be identified efficiently and accurately. At the same time, it also provides a new idea for the identification of the diagenetic facies of old oilfields with only logging image data sets. [ABSTRACT FROM AUTHOR]

Polyethers are a class of base oils with good solubility, thermal stability, shear resistance and lubricity and are widely used in chemical, electronic, mechanical and material fields. Polyalkylene glycol (PAG) base oils have attracted much attention in industry for their non-corrosive, non-toxic and structural designability. This review first describes the relationship between structural properties and lubrication characteristics of PAG. Secondly, the main synthesis strategies of PAG are analyzed and reviewed. The industrial applications and their characteristics based on PAG are summarized to support future studies on the formation of high-value-added PAG derivative products. [ABSTRACT FROM AUTHOR]

Nanostructures as an inert additive to the lubricant act as a tiny friction reduction element by providing asperity filling, polishing, and film formation mechanism at the nanoscale dimension under the boundary layer regime. Here, we explore the synthesis and tribology application of iron‐carbon‐based nanoparticles encapsulated multiwall carbon nanotubes (Fe‐C‐CNTs). Three Fe‐C nanoparticles phase that is, Fe3C‐CNTs, Fe3C‐Fe‐CNTs, and Fe‐CNTs are synthesised. In particular, the emphasis here is on the effect of nanoparticle phase variation on the tribology property. The tribology property of the prepared nanomaterials is studied by dispersing it in commercially used Servo gearbox oil. The coefficient of friction and wear is found reduced in all dispersions compared to the base gearbox oil confirming the manifestation of nanoscale mechanisms at the tribo‐interface. It is revealed that the phase variation shows more impact on the alteration of friction coefficient compared to the dispersion concentration variation analysed using ANOVA two‐way technique. Further, the diameter and composition analysis of the wear scar is used to comprehend the underlying mechanism of the encapsulated particle phase variation. The findings suggest that the Fe‐CNTs dispersions are efficient in reducing friction to a larger extent but also promote the interface oxidation leading to enhanced wear and roughness whereas, Fe3C‐CNTs and Fe3C‐Fe‐CNTs are chemically stable providing smooth sliding and less wear. [ABSTRACT FROM AUTHOR]

Rationale: Fully formulated oils (FFOs) are chemically complex petrochemical products composed of base oil and additive mixtures that are employed in automotive engines to provide lubrication. In particular, the additive portion of FFOs is often precisely controlled to tailor the resultant formulation to a specific role. Analysis of the additive composition of both used and unused FFOs is therefore of great importance within the petroleum, automotive, and wider engineering industries. Methods: A simple and rapid reversed‐phase high‐performance liquid chromatography–tandem mass spectrometry method is reported herein for the analysis of a range of additives commonly encountered in FFO samples. Mass spectrometry was performed using an LTQ Orbitrap XL instrument using both positive‐ and negative‐ion electrospray ionization. Tandem mass spectra were acquired in the data‐dependent mode. FFO samples were analysed with minimal sample preparation, limited in this case to simple dilution steps. Results: The reported method permits analysis of a range of antioxidant, detergent, and antiwear chemistries from various FFO samples in under 10 min. Additionally, it is demonstrated that additive confirmation can be performed and some structural information obtained using the data‐dependent tandem mass spectrometry method. Furthermore, analysis of additives and corresponding degradation products within a used FFO is reported. Conclusions: The results obtained using the reported methodology are of demonstrable use in numerous industries and applications, and readily return an abundance of information on the additive composition of a range of FFO samples. Anticipated applications of the methodology include but are not limited to quality control, suspected counterfeit analysis, and FFO degradation analysis. [ABSTRACT FROM AUTHOR]

The complex dynamics of tribofilm formation on boundary-lubricated steel surfaces were investigated in real time by combining in situ measurements of the temporal variation of the coefficient of friction and contact voltage. Sliding experiments were performed with various blends consisting of base oil, zinc dialkyl dithiophosphate (ZDDP) additive, and two different dispersants at an elevated oil temperature for a wide range of normal load and fixed sliding speed. The evolution of the transient and steady-state coefficient of friction, contact voltage, and critical sliding distance (time) for stable tribofilm formation were used to evaluate the tribological performance of the tribofilms. The blend composition affected the load dependence of the critical sliding distance for stable tribofilm formation. Tribofilm friction was influenced by competing effects between the additive and the dispersants. Among various formulations examined, the tribofilm with the best friction characteristics was found to be the blend consisting of base oil, a small amount of ZDDP, and a bis-succinimide dispersant treated with ethylene carbonate. The results of this study demonstrate the effectiveness of the present experimental approach to track the formation and removal of protective tribofilms under boundary lubrication conditions in real time. [ABSTRACT FROM AUTHOR]

A simple and accessible method has been developed for the preparation of copper‐containing nanocomposites by thermolysis of a copper(II) complex with a Schiff base based on 3‐formyl‐4‐hydroxycoumarin and octadecylamine at 500 °C. The resulting nanoparticles with a particle size of up to 85 nm were used as additives to lubricants. It has been established that copper oxide nanoparticles with a concentration of 0.5 % and 1 % increase the anti‐wear and anti‐friction properties of the lubricant. [ABSTRACT FROM AUTHOR]

During the development of a sand-conglomerate reservoir, there is a huge variation in rock grain size and different åmineral compositions of different-sized sand grains. The mineral composition and microstructure of the rock both have an impact on the characteristics of the remaining oil in the reservoir. The stripping mechanism of a surfactant system on sand-conglomerate surface crude oil with varied grain size minerals was explored in this paper. Sand-conglomerate was classified and analyzed to determine their wettability and stripping oil effects. The optimization of the surfactant solution system and molecular dynamics simulation revealed the surfactant stripping mechanism on crude oil on distinct sandstone minerals. The results of the study showed that montmorillonite minerals are more readily adsorbed by surfactants. The crude oil within them is more likely to compete for adsorption and to be stripped off, and then extracted with the recovery fluid. The surfactant solution system can increase the hydrophilicity of the rock surface, make the crude oil on the rock surface shrink and gather, and enhance the transportation ability of the displacement fluid. And the emulsification seals part of the pore in the reservoir, increases the displacement pressure, and improves the overall wave volume. The results of this paper are of great significance for the efficient development of sand-conglomerate reservoirs. [ABSTRACT FROM AUTHOR]

Heavy oil holds a pivotal position in the global energy landscape and plays a significant role in meeting the increasing energy demand worldwide. The utilization of multi-thermal fluids(comprising supercritical steam, CO2, and N2) in cyclic solvent injection (CSI) techniques overcomes the challenges associated with conventional steam flooding techniques such as high energy consumption, low heat utilization and poor performance, and becomes a promising technique for enhancing heavy oil recovery. However, the presence of surface-active substances in heavy oil and the complex composition of multi-thermal fluids leads to the formation of complex and stable emulsions during the cyclic multi-thermal fluids injection process, which poses challenges to subsequent demulsification. This study first elucidates the properties of heavy oil based on heavy oil component analysis, microscopic examination of asphaltene morphology and functional groups. Subsequently, the stability of emulsion generated during the cyclic multi-thermal fluids injection process is investigated based on water segmented ratio and particle size distribution of emulsion droplets. Furthermore, the stability mechanisms of emulsion are studied using scanning electron microscopy and infrared spectroscopy techniques. Finally, the effect of the polyether-type demulsifier on facilitating the dehydration of heavy oil emulsion is evaluated. The findings of this research provide theoretical insights to guide the development of efficient demulsifiers for cyclic multi-thermal fluid injection process. [ABSTRACT FROM AUTHOR]

Background and Aim: The objective was to evaluate the effect of a cream based on the essential oil of Origanum vulgare on skin lesions induced in Mus musculus Balb/c. Materials and Methods: The experimental animals were divided into four groups of 6 specimens each, in which skin lesions of approximately 1 cm in diameter were induced. Group I (Control) received no treatment, Group II (0.1% Origanum vulgare cream), Group III (0.5% Origanum vulgare cream), and Group IV (1% Origanum vulgare cream) received treatment for eight days. Skin lesions were measured on days 4 and 7. At the end of treatment, they were euthanized using sodium pentobarbital 60 m/kg v.ip. Skin samples were obtained and preserved in 10% formalin for histopathological analysis. Results: When measuring the size of the skin lesions induced in the study groups, it was observed that in the control group, the decrease in the length of the lesions occurred on the fifth day; in group II, III, and IV, the lesions length decrease occurs on the second day. At the end of the experience, the measurements of the lesions were much smaller for the III and IV groups (0.33 and 0.41, respectively) compared to the control group (0.40 cm). On day seven, statistically significant difference was found on skin lesion measure between Group IV and the Control, with a significance level of p<0.05. Conclusion: It is concluded that the 1% Origanum vulgare essential oil-based cream has a healing effect on dermal lesions induced in Mus musculus Balb/c. [ABSTRACT FROM AUTHOR]

Oil-water interfaces that are created by confining a certain amount of oil in a square shaped pixel (∼200 x 200 μ m 2 with a height of ∼10 μm) topped by a layer of water, have a curvature that depends on the amount of oil that happens to be present in the confining area. Under the application of an electric field normal to the interface, the interface will deform due to inhomogeneities in the electric field. These inhomogeneities are expected to arise from the initial curvature of the meniscus, from fringe fields that emerge at the confining pixel walls and, if applicable, from interfacially adsorbed particles. We model the shape of the confined oil-water interface invoking capillarity and electrostatics. Furthermore, we measure the initial curvature by tracking the position of interfacially adsorbed particles depending on sample tilt. We found that the pixels exhibited meniscus curvature radii ranging from 0.6-7 mm. The corresponding model based minimum oil film thicknesses range between 0.7 and 9 μm. Furthermore, the model shows that the initial meniscus curvature can increase up to 76 percent relative to the initial curvature by the electric field before the oil film becomes unstable. The pixel wall and particles are shown to have minimal impact on the interface deformation. • Deformation by an electric field of a confined liquid-liquid interface is modeled. • The meniscus curvature can be increased up to 76% by the applied electric field. • The curvature was quantified by tracking the position of interfacially adsorbed particles. • Fringe fields and colloidal particles have no significant impact on global curvature. [ABSTRACT FROM AUTHOR]

The evaluation of shale reservoir quality is of great significance for the exploration and development of shale oil. To more effectively study the distribution characteristics of shale reservoir quality, thin-section observation, scanning electron microscopy and pressure-controlled porosimetry were used to obtain the pore structure characteristics of shale in Chang 7, including pore types, pore size distribution, etc. In addition, the fractal dimensions of the shale samples were calculated based on pressure-controlled porosimetry data. The results show that residual interparticle pores, dissolution pores and clay-dominated pores were the main pore types. The overall pore size was mainly distributed between 3 nm and 50 μm. The pore system was divided into four types using fractal features, and the shale reservoir was divided into four types based on the proportion of different types of pore system. In different types of reservoirs, the production capacity of exploration wells varies significantly, as does the production capacity of horizontal wells. The classification of shale reservoirs using mercury intrusion fractal analysis proved to be suited for the efficient development of Chang 7 shale oil reservoirs. [ABSTRACT FROM AUTHOR]

Derivatives of 2,4-dimethyldihydrocyclopentadiene were prepared, characterized by NMR spectroscopy, which was applied to 1-decene oligomerization. A two-step activation method in which both triisobutylaluminium (TIBA) and methyl aluminoxane (MAO) were co-used in sequence particularly been developed for N-doped ligand catalyst. N-doped catalyst had a very high polymerization conversion at 60–110 °C by varying the reaction temperature at 20 eq. of TIBA and 100 eq. of MAO, reaching 89.95% at 80 °C. In addition, oligomers with different viscosity grades could be obtained by adjusting the temperature. At optimized reaction conditions 75 °C, 10 eq. of TIBA and 50 eq. of MAO activation, the single pass conversion of 91.33% was achieved. The obtained oligomers had a high viscosity index above 170 at KV100 = 6. In addition, the two-step activation method was used to compare with the conventional one-step activation method on catalysts with three different ligands of zirconium chloride. A high catalytic productivity was achieved by the two-step activation process. Depending on the nature of the ligands used, β-hydride elimination, 2,1 insertion and 1,2 rearrangement were detected as main chain release mechanisms. Meanwhile, the pathways of oligomer formation were also summarized. In brief, N-doped complex is promising catalysts for the production of high quality lubricant base oils due to their high catalytic activity and high thermal stability. [ABSTRACT FROM AUTHOR]

This paper analyses the attributes and the significance of the roughness of oil market volatility. We employ unspanned stochastic volatility models driven by rough Brownian motions that yield semi-analytical prices for future options entailing efficient calibration applications. By performing a Monte Carlo simulation study, we show that the semi-analytical pricing performs well thus establishing its efficiency for calibration applications. Thus we calibrate option prices written on oil futures and provide empirical evidence of the roughness in oil volatility. Introducing just one additional parameter, the Hurst parameter, indicating the roughness of the volatility improves the calibration by almost a factor of 10. The calibrated option-implied Hurst parameter varies over time, but the entire set of parameters becomes more stable than in the non-rough case corresponding to a fixed Hurst parameter 1/2. These results underscore the importance to model the time dependency of the roughness of oil market volatility. [ABSTRACT FROM AUTHOR]

Due to the high viscosity of Jimsar crude oil and the lipophilicity of the reservoir, CO2 has an excellent performance in development of Jimsar shale oil. However, previous studies mostly focused on CO2 fracturing, but the replacement of crude oil by CO2 is rarely reported. Therefore, we conducted research on oil replacement by CO2 through systematical experiments. Firstly, we designed an experimental approach based on nuclear magnetic resonance to quantify the replacement ratio of oil. Next, a series of experiments were conducted for analyzing the effect of pressure, soaking time, permeability, and fractures on replacement ratio. Finally, oil-water imbibition experiments were conducted to compare its development effect with CO2 replacement for target reservoir. The study shows that the replacement capacity of CO2 for crude oil increases with pressure. In the experiment, the replacement ratio increases from 27.46% (10 MPa) to 56.70% (40 MPa) after 24 hours. On the microscopic scale, the crude oil in large pores is replaced out firstly, then the smaller pores. And on the macroscopic scale, the replacement of crude oil is from outside to inside. High permeability and fractures in the core promote the intrusion of CO2 into the core, raising the replacement ratio significantly. Since Jimsar reservoir is oil-wet, the oil recovery of oil-water imbibition is far less than that of CO2 replacement. The minimum pore through which oil can be exploited by oil-water imbibition is 1 μm, while for CO2 replacement the value is 0.08 μm. This study provides fundamental for CO2 increasing oil recovery in Jimsar shale oil. [ABSTRACT FROM AUTHOR]

Engine oil oxidation is one of the major reasons for oil aging which can result in variations in the physical and chemical properties of oil. Organic acids generated by oil oxidation can react with water to form inorganic acids and acidic substances (including organic and inorganic acids) that corrode engine parts, resulting in the generation of rust or damage to engine parts. This is one of the important reasons why oil should be regularly changed. One of the most commonly applied methods for judging the aging degree of engine oil is monitoring its acid number (AN). However, generally, the effect of oil water content on acid value measurement is not considered. When oils are used in engines, they are often contaminated by water due to condensation, which accelerates engine oil aging. Therefore, it is crucial to explore the water content effect on AN in the process of engine oil aging. In this research, a water content sensor was applied to characterize moisture content in oxidized oil samples. The sensor could also obtain oil sample electrical conductivity which corresponded to its dielectric constant. Using a mid-infrared spectrometer to measure oil sample AN at this point to obtain the variation in AN with oxidation time, oil sample AN was connected in series with the water content, dielectric constant and electrical conductivity. These parameters were monitored through sensors, and the effect of water content on AN was studied. Experimental results revealed that with the increase in oxidation time, the water content, electrical conductivity, dielectric constant increase and AN of oil were increased. At the same time, since the temperature had a greater effect on electrical conductivity, the application of an air-conditioned constant-temperature environment removed the effect of temperature change on electrical conductivity. [ABSTRACT FROM AUTHOR]

The behavior of oil sunflower seeds penetrating screen holes is an important factor that affects the screening performance of oil sunflower seeds. In this study, a double-deck reverse-motion vibrating screening device for oil sunflower seed screening was designed. The force condition and motion law of the oil sunflower seeds on the screen surface were analyzed. This study compared the effect of particle filling amount of discrete element model of oil sunflower seeds on the simulation effects. The screening process was numerically simulated using the coupled Discrete Element Method and Multibody Dynamics (DEM-MBD) technique with the screening percentage of oil sunflower seeds as the index. The influence of the operating parameters of the vibrating screen on the screening effect was analyzed using a multiparameter collaborative optimization scheme. The results of this study can provide a reference for the numerical simulation of crop screening behavior and the development of screening devices. [ABSTRACT FROM AUTHOR]

Summary: The presence of trans fatty acid in food is often reduced through the use of fat replacers or oleogel technology. However, these alternatives typically encounter a scarcity of resources, specifically vegetable oil, which serves as the primary raw material. In fact, oil derived from marine, particularly fish oil by‐products, can be valorised as a colloidal architecture. Therefore, this study aims to assess the optimal type of oleogelator by applying different concentrations of beeswax (BW) and rice bran wax (RBW) in the generating of oleogel based on fish oil by‐product. Oleogel thermogram showed a shift in the melting point with increasing temperatures for concentrations of 5%, 10% and 15%. Oleogel containing 15% BW and 5% BW had the highest (99.27 ± 0.55%) and lowest (78.20 ± 2.54%) oil binding capacity, respectively. The rheology evaluation showed dynamic shifts in oleogel system as the type and concentration of oleogelator were altered, underscoring the importance of G′ and G″. The use of a 10% oleogelator generated preferable results for both BW and RBW in terms of melting point, OBC, viscous behaviour and appearance of oleogel. Furthermore, this selected oleogel strategy exhibited similar textural properties to commercial margarine when used in a sponge cake as the food model system. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the production of mayonnaise containing oleogel prepared based on sesame oil and organogelators of ethyl cellulose and carnauba wax and to evaluate its physicochemical and organoleptic properties. In this research, the optimization of oleogel production was done based on the hardness and oil migration rate, and the treatment containing 7.41 grams of carnauba wax and 4.41 grams of ethyl cellulose was selected as the optimal treatment. Then 5 types of mayonnaise samples were prepared and physicochemical and sensory tests were performed on them on days 1, 30 and 60. During the storage period, the amount of replaced oleogel had an inverse relationship with peroxide index, thiobarbituric acid and the amount of released oil and a direct relationship with the emulsion stability of the samples. Also, the results showed that the storage time has no significant effect on the color characteristics of the samples; But with increasing amount of oleogel, the *L component of the samples decreases, but the *a and *b components of the samples increase. In the organoleptic evaluation, at the end of the shelf life, all the treatments were in the optimal and moderate range. Therefore, the results showed that mayonnaise with desirable physicochemical and sensory properties can be prepared using oleogels based on sesame oil and organogels of ethylcellulose and carnoba wax. [ABSTRACT FROM AUTHOR]

The walnut oil oleogels prepared by beeswax and monoglyceride was used as the research object and the effects of ultrasound treatment before or after complex oleogelators melting on the structure and properties of the walnut oli oleogels were explored. The research results indicated that when the mass ratio of beeswax to monoglyceride was 3:7, the formed walnut oil oleogels had an oil bonding capacity (OBC) of over 95% and a smooth and stable surface morphology. All walnut oleogels showed solid-like elastic properties within a certain shear strain range, and the walnut oil oleogels prepared with 100 W-30 s parameters had the strongest mechanical properties. Ultrasound treatment could improve the crystal structure of walnut oil oleogels, produce more compact and fine crystal morphology, and effectively enhance OBC and thermal stability of walnut oil oleogels. The oleofoams obtained by whipping the oleogels exhibited excellent decorative performance, and ultrasound treatment could significantly increase the overrun of the walnut oil oleogels. In sum, ultrasound treatment could improve the structure and properties of walnut oil oleogel, and make it a good substitute for margarine. Key words:walnut oil oleogel;beeswax;monoacylglycerol;ultrasound treatment [ABSTRACT FROM AUTHOR]

As conventional oil reservoirs are gradually being depleted, researchers worldwide are progressively shifting their focus towards the development and comprehensive study of tight oil reservoirs. Considering that hydraulic fracturing is one of the main approaches for developing tight sandstone reservoirs, it is of great significance to explore the mechanism of spontaneous imbibition and waterflooding behavior after hydraulic fracturing in tight oil reservoirs. This research delves into the analysis of tight sandstone core samples obtained from the Shahejie Formation in the Bohai Bay Basin. All core samples are used for a series of experiments, including spontaneous imbibition and water flooding experiments. An additional well-shut period experiment is designed to understand the impact and operational dynamics of well shut-in procedures in tight reservoir development. Utilizing nuclear magnetic resonance (NMR) technology, the pore sizes of a sample are divided into three types, namely, macropores (>100 ms), mesopores (10–100 ms), and micropores (<10 ms), to thoroughly assess the fluid distribution and changes in fluid signals during the spontaneous imbibition and water flooding stages. Experimental outcomes reveal that during the spontaneous imbibition stage, oil recovery ranges from 12.23% to 18.70%, predominantly depending on capillary forces. The final oil recovery initially rises and then falls as permeability decreases, while the contribution of micropores progressively grows as the share of mesopores and macropores deceases. With water flooding processes carried out after spontaneous imbibition, enhanced oil recovery is observed between 28.26% and 33.50% and is directly proportional to permeability. The well shut-in procedures can elevate the oil recovery to as high as 47.66% by optimizing energy balance. [ABSTRACT FROM AUTHOR]

The limited dispersion stability of graphene in lubricating oils and the high cost of chemical deposition method to prepare SiO2/GO composite materials. The samples were analyzed by X-ray diffraction, Raman spectroscopy, thermogravimetric analysis, transmission electron microscopy, scanning electron microscope. The test results demonstrate the ideal anchoring of SiO2 materials on GO surfaces. The tribological properties of SiO2/GO nanomaterials as the base oil additive were investigated using a four-ball tribometer. The addition of SiO2/GO nanocomposites to the lubricating oil enhances its lubrication performance, resulting in a significant reduction of 38.6% and 29.7% in friction coefficient and wear scar diameter compared to the base oil. The prominent lubrication properties of SiO2/GO nanocomposites are attributed to their excellent dispersion and ultra-thin shape, which enable them to enter contact surfaces and act as protective films that prevent direct contact with each other. Compared with the previous research, the rheology was innovatively introduced, the rheological test of the lubricating oil was conducted, and its results were correlated with the friction data. The rheological data were fitted to analyze and understand the lubrication mechanism, providing a novel perspective for studying lubricating oils. SiO2/GO composites exhibited excellent performance due to their low cost and lubrication, which is the future direction of commercial lubricant development. It can be extensively utilized in the domains of automotive engines and heavy machinery, which exhibits promising potential applications. SiO2 nanomaterials were grown fully on the layered GO nanoflakes prepared by the sol–gel method, giving rise to a novel microstructure of SiO2/GO as additives materials for lubricating oil. The character of the SiO2/GO is easily deposition on friction interface. [ABSTRACT FROM AUTHOR]

[Display omitted] Hydrogel coatings have received great attention in the field of such as medical devices, water treatment membranes, flexible electronics, and marine antifouling. However, when it comes to lubrication of hydrogel materials, though it has great potential applications in the field of industrial and medical drag reduction, some restrained properties are urgently needed to overcome for releasing the practical potential. Durability of high lubrication was revealed from the sliding test during the long-term storage, as well as the long-distance sliding. Some variables which possibly affect the lubrication performance were examined to demonstrate that excellent lubricity of the coating would not be easily influenced by load, frequency, friction pair and temperature. The microstructure and mechanical characterization of the lubricative coating indicate that the resistance to harsh running conditions is premised on enough hydration extent and robustness. The formulae of Possion ratio and ball-on-disk contact stress which apply to soft matter were used for calculating contact stress values in tribology tests. Anti-swelling and bio-compatibility are also verified. This work found a route of achieving superior lubrication and coexisting with stability in lubrication, which can be used for drag reduction in medical devices and shipbuilding industry. [ABSTRACT FROM AUTHOR]

In this work, we aim to understand and predict the thermal properties of automotive lubricants using non-equilibrium molecular dynamics. After a previous study on model materials for the mechanical parts of a car engine, we now focus on the thermal conductivity κ of the poly- α -olefin base oil (PAO4) using the well-known sink and source method to study the response of the system to an imposed heat flux. We present a detailed methodology for the calculation of κ , taking into account specific constraints related to the system under study, such as large steady-state fluctuations and rapidly growing stationarization times. We provide thermal conductivity results using four different force fields, including OPLS-AA, PCFF and COMPASS, in a temperature range of 300 to 500 K, which corresponds to the typical operating range of a car engine. The results are compared to experimental measurements performed on the commercial compound using the laser flash method. Agreement at room temperature is shown to be excellent for our in-house force field. [ABSTRACT FROM AUTHOR]

Frequent diaphragm rupture of diaphragm compressors is a severe issue in hydrogen refueling stations, generally occurring when the diaphragm collides violently with the oil plate. The oil pressure exhibits distinct properties in different working conditions, due to the oil-gas cooperative working characteristics of diaphragm compressors. This paper proposes a diagnosis method to identify the state of the diaphragm, separating the maximum and minimum oil pressures from the complex working parameters as characteristic signals. Especially, this method can forewarn the collision. The precise reason for the failure can also be identified combined with the overflowed oil flow. Several common fault types were reproduced and evaluated to verify this method's reliability. Experimental results confirmed that this method could accurately identify the diaphragm states, and can issue a collision warning 25 min in advance for a 45 MPa diaphragm compressor even in accelerated tests. [Display omitted] • A diagnosis method was proposed to identify the diaphragm state. • This method is based on dynamic oil pressure and overflowed oil flow. • This method can issue a warning of a collision and analyze the fault reasons. • Experimental validations are performed and prove the reliability of this method. [ABSTRACT FROM AUTHOR]

Most regions of the world, including the Algerian desert (southeast of Algeria, the El-Oued region in particular) suffer from pure water scarcity, although there is a huge stockpile of groundwater, it is salty water. Solar stills are one of the best solutions to the problem of freshwater shortages because it depend on solar energy, which is abundant throughout the year in southeastern Algeria. Due to the low productivity of solar stills, the current experimental study aims to create simple and inexpensive solutions to improve the productivity of solar stills. This was done by manufacturing the absorption basin from a concrete layer, with the addition of cement cylindrical fins and which were used as energy storage materials in addition to the use of cylindrical fins helped to increase the heat transfer area between the absorption surface (thermal storage materials) and basin water. To achieve this goal, two single-slope solar distillers were built and tested in this article, the first is Single Slope Solar Distiller with a Cement Layer (2 cm) placed as absorbent at the bottom base of the basin (SSSD-CL) and the second is a Single Slope Solar Distiller with Cement Layer (2 cm) and Cement Cylindrical Fins (SSSD-CL&CCF). Cylindrical fins are made of cement with a diameter of 1.5 cm and a length of 3 cm. The results showed that SSSD-CL&CCF produced drinking water at a rate of 4.52 kg/m²/day while SSSD-CL produced only 3.46 kg/m²/day, which is 30.64% more compared to SSSD-CL&CCF. These results demonstrated that the drinking water produced by SSSD-CL improved by incorporating the cement cylindrical fins with the cement layer as low-cost and available sensible thermal energy storage materials. Also, Cement cylindrical fins were used, which increased the thermal and exergy efficiency by 31% and 56.7%, respectively. [ABSTRACT FROM AUTHOR]

Assessment of the aging of oil‐paper insulation is analyzed in this article, based on an improved fractional Poynting‐Thomson model, which includes dc and hopping conductivity (P‐T model2). Based on samples of oil paper produced in laboratories with different thermal aging times, it has been found that the proposed improved model provides a better fit and a higher index of coincidence concerning the measured values than the traditional P‐T model and the model that only incorporates the effect of dc conductivity (P‐T model1). Nevertheless, comparing the proposed improved P‐T model with the traditional Cole–Cole (C‐C), Davidson–Cole (D‐C), and Havriliak–Negami (H‐N) models, the improved P‐T model2 also demonstrated a superior fit for the measured value and a higher coincidence index than another model. In addition, there was an excellent exponential relationship between the quantities εa, εb and τ of the improved model and the furfural content of the samples. Consequently, these characteristic quantities could be utilized to estimate the furfural content in the oil‐paper insulation and evaluate the insulation's condition. © 2023 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Supramolecular gelator functionalized liquid metal (Gelator@GLM) exhibited excellent tribological properties due to the synergistic effect of GLM nanodroplets and the gel generating protective film. [Display omitted] • Supramolecular gelator functionalized liquid metal nanodroplets were prepared by self-assembly and radical polymerization. • The Gelator@GLM nanodroplets displayed effective anti-wear and friction reduction properties as lubricant additives. • The lubrication performance is attributed to the synergistic effect of GLM nanodroplets and the gel generating protective film. In this work, dopamine n -butenylamide (DBA) modified GLM nanodroplets were prepared via directional ultrasound of bulk liquid metal in ethanol aqueous solution as well as DBA self-assembly, followed by grafting with urea-based gelators via radical polymerization to obtain GLM-based supramolecular gelators (Gelator@GLM). The grafting gelators can impart their good compatibility between the GLM nanodroplets and the base oil, so that the Gelator@GLM nanodroplets can be dispersed in the base oil uniformly and stably for more than 3 weeks. Meanwhile, the tribological properties of Gelator@GLM nanodroplets was significantly enhanced, with a reduction of coefficient of friction (COF) and the wear volume of 41.18% and 92.13%, respectively, when compared with the base oil. Furthermore, Gelator@GLM additives exhibited stable lubrication performance even under variable temperature and frequency conditions. The synergistic effect of GLM nanodroplets and the gels generating a physical adsorption film and a chemically protective film (containing iron and chromium oxides, nitrides and carbides) can be credited with the improved tribological performance. [ABSTRACT FROM AUTHOR]