Search

The purpose of this study is to investigate the physical and mechanical properties of local carbon materials and the warm compaction method in the production of current collectors for light rail transit (LRT) applications. The problem here is that the current collectors used by the railway industry in Malaysia for the LRT are still imported from foreign countries which is very costly. Furthermore, the production method of commercial current collectors, namely C-Cu composites, is compact and sintered, which also results in relatively high costs. Therefore, this study focuses on replacing the old materials and methods of commercial current collector production with new materials and methods. This study used a local carbon, which is the kernel shell of oil palm as the main carbon for the production of current collectors. The compact and sintered production methods are then replaced by warm compaction and post-heating methods. The current collectors that had been produced are then cut into several samples to allow them to be tested in a number of physical and mechanical tests. Based on the test results, when using these new materials and methods, the density and hardness were observed to be slightly lower at 1.81 g/cm³ and 122.6 HRR compared to the commercial current collectors, which have a density of 2.2 g/cm³ and 126.9 HRR. Meanwhile, in the transverse rupture strength (TRS) and resistivity tests, the warm compaction method based on oil palm kernel shell demonstrated higher values of 175.1 MPa and 1631 Ω-cm, respectively, compared to the commercial current collectors which showed values of 58.71 MPa and 598.77 Ω-cm. In conclusion, there are various advantages and disadvantages between the new current collectors and the commercial current collectors in terms of mechanical as well as physical characteristics. Therefore, various improvements and suggestions need to be made in order to produce physically and mechanically better current collectors to be used in LRT applications. [ABSTRACT FROM AUTHOR]

High internal phase emulsions (HIPEs) are commonly stabilized by a large amount of surfactants that should be removed after the polymerization of the continuous phase, and the resulting polyHIPEs from W/O HIPEs are usually brittle and chalky. Herein we report on an amphiphilic polymerizable polyurethane (PPU) macromolecular surfactant synthesized by polyaddition reaction of diisocyanates and polyols, which can well stabilize up to 88% internal phase volume of W/O HIPE with a content of only 5 wt% based the oil phase. Compared with the HIPEs stabilized by traditional surfactant Span 80, HIPEs stabilized by PPU at either room temperature or 70 °C are much more stable owing to the increased viscosity which can inhibit droplet coalescence. Moreover, the resulting polyHIPEs not only have several times higher mechanical properties than those stabilized by Span 80 but also have higher elasticity. The effects of concentration of PPU on the morphology and mechanical properties of the resulting polyHIPEs were investigated. It was found that with the increase of PPU content, the average void and window sizes decreased, while the compression strength increased. Cyclic compression tests were performed to examine reversible compressibility and durability of these polyHIPEs. The polymerizable polyurethane macromolecular surfactant (PPU) synthesized through the polyaddition reaction of diisocyanates and polyols can solely stabilize high internal phase emulsions (HIPEs), and highly interconnected macroporous polymer produced by the polymerization of HIPE stabilized with PPU, known as polyHIPE, can withstand large deformation compression with no visible cracks. [ABSTRACT FROM AUTHOR]

Efficient cooperative lubrication can be achieved via the introduction of core-shell structure lubricant additives with hard core and soft shell, for obtaining the expected anti-wear performance from the structural changes in the friction process. In this study, C@Ag microspheres with a core-shell structure were prepared by the redox method with carbon spheres as the core and Ag nanoparticles as the shell. Their tribological behaviors as base oil (G1830) additive with different concentrations were investigated in detail. Compared with base oil, the addition of C@Ag particles at 0.5 wt% can reduce the coefficient of friction (COF) and wear volume (Wv) up to 15.5% and 88%, respectively. More importantly, C@Ag particles provide superior lubrication performance to single additive (like carbon sphere (CS) and Ag nanoparticle). C@Ag core-shell particles contribute to the formation of tribo-film by melt bonding of flexible Ag and carbon sphere (CS) toward excellent self-repair performance and high-efficiency lubrication. Hence, core-shell structural nanoparticles with hard-core and soft-shell hold bright future for high-performance lubrication application. [ABSTRACT FROM AUTHOR]

Introducing an additive is a practical approach to improve the lubrication performance of base oil in the field of tribology. Herein, a series of sulfoximine derivatives was synthesized and incorporated into base oil A51 as additives. The tribological properties of these lubricants were evaluated at both room and high temperatures, and the result demonstrated that they displayed excellent friction reduction and wear resistance in the friction process under both test conditions. Moreover, the chemical composition of the worn scar surface was inspected using EDS, XPS and TOF-SIMS to explore the lubricating mechanism. It is reasonable to conclude that the synergistic interaction between the aromatic ring scaffolds and elements like N, F, and S facilitated the adsorption of lubricant on the steel block surfaces and forming a tribofilm during the friction process. This tribofilm has a dominant impact on the system's lubrication performance. This research provides novel oil-soluble lubricant additives, offering a facile approach to formulating high-quality lubricants. [ABSTRACT FROM AUTHOR]

A method for obtaining non-isocyanate polyurethane (NIPU) foams from cyclic carbonate (CC) based on soybean oil was developed. For this purpose, cyclic carbonate was synthesized from epoxidized soybean oil and CO2 using various ionic liquids (ILs) as catalysts. Among the tested ILs, the highest selectivity (100%) and CC yield (98%) were achieved for 1-ethyl-3-methylimidazolium ([emim]Br). Without any purification, the resulting cyclic carbonate was reacted directly with diethylenetriamine as a model crosslinking agent to produce NIPU foams. It was found that the soybean oil-based CC synthesized with bromide imidazolium ionic liquids exhibited significantly shorter gelling times (8 min 50 s for [emim]Br and 9 min 35 s for [bmim]Br) compared to those obtained with the conventional TBAB catalyst (26 min 15 s). A shorter gelling time is a crucial parameter for the crosslinking process in foams. The obtained foams were subjected to mechanical tests and a morphology analysis. [ABSTRACT FROM AUTHOR]

Approximately half of the lubricants sold globally find their way into the environment. The need for Environmentally Acceptable Lubricants (EALs) is gaining increased recognition. A lubricant is composed of a base oil and multiple functional additives. The literature has been focused on EAL base oils, with much less attention given to eco-friendly additives. This study presents the tribological performance and aquatic toxicity of four short-chain phosphonium-phosphate and ammonium-phosphate ionic liquids (ILs) as candidate anti-wear and friction-reducing additives for EALs. The results are benchmarked against those of four commercial bio-derived additives. The four ILs, at a mere 0.5 wt% concentration in a synthetic ester, demonstrated a 30–40% friction reduction and >99% wear reduction, superior to the commercial baselines. More impressively, all four ILs showed significantly lower toxicity than the bio-derived products. In an EPA-standard chronic aquatic toxicity test, the sensitive model organism, Ceriodaphnia dubia, had 90–100% survival when exposed to the ILs but 0% survival in exposure to the bio-derived products at the same concentration. This study offers scientific insights for the future development of eco-friendly ILs as lubricant additives. [ABSTRACT FROM AUTHOR]

Introduction: The traditional partial discharge localization improvement strategy mainly starts from the intelligent algorithm, but fails to consider the influence of core winding and oil temperature on partial discharge positioning. Methods: This paper also considers the influence of the iron core winding and oil temperature. Through finite element simulation, a transformer model was established to analyze the propagation characteristics of ultrasonic signals generated by partial discharge under the interference of gradient oil temperature and winding. The chaotic firefly-particle swarm hybrid algorithm is proposed, and through the calculation of Shubert's multi-peak function. Finally, a partial discharge defect platform based on gradient oil temperature was built to verify the chaotic firefly-particle swarm hybrid localization algorithm. Results: The ultrasonic velocity generated by partial discharge in transformers cannot be fixed, and it is suggested that ultrasonic sensors should be installed near the center of the top of the transformer. The proposed algorithm can be better optimized in the case of multiple local extreme points. Under gradient oil temperature experiments, the algorithm achieves positioning errors less than 100 and 55 mm for cases with and without winding obstruction, respectively, with average positioning errors of 74.2 and 35.2 mm. Discussion: The positioning method in this paper can provide a technical reference for the partial discharge positioning of transformers in actual operation. [ABSTRACT FROM AUTHOR]

Lubricant base oils, traditionally derived from non-renewable petroleum, contribute significantly to greenhouse gas emissions. In contrast, oils sourced from furfural and long-chain ketones through aldol condensation and hydrodeoxygenation present a renewable, cost-effective, and environmentally friendly alternative, offering superior cold flow properties. However, the production of long-chain ketones, a crucial component, currently relies on solvent dewaxing in refineries, which is costly and non-selective. One promising biobased approach involves self-ketonization of long-chain fatty acids derived from coconut or palm kernel oils. This method typically employs high boiling point solvents like dodecane or is done in a batch configuration, limiting its scale and industrial viability. This study addresses this bottleneck by eliminating solvents, transitioning to a continuous flow reactor, and achieving kilogram-scale production of long-chain ketones with exceptional selectivity (90%). The lab-scale setup can yield up to 25 kg of 12-tricosanone per month, utilizing earth-abundant MgO as a catalyst. The catalyst underwent slight deactivation due to carbonate formation. Catalyst stabilization, using mixed metal oxides, and regeneration via simple calcination in air are also discussed. Techno-economic analysis (TEA) indicates a 29% lower minimum selling price than the commercial synthetic poly alpha olefin (PAO). Life cycle assessment (LCA) evaluates the global warming potential (GWP) under different environmental assumptions. Under the carbon-neutral assumption for lauric acid production, an 8.9% reduction in GWP was achieved compared to petroleum-based lubricants. [ABSTRACT FROM AUTHOR]

The present paper illustrates the results of an experimental study aimed at evaluating the effect of lubricant oil features on the emissive behaviour of a heavy duty spark ignition engine fuelled with methane. The activity was performed within a research project between CNR-STEMS and TotalEnergies in which oils with different formulations were characterized, focusing on their potentiality in particle emission reduction. Considering the ultralow particle emission level in the exhaust of gas engines, a specific testing procedure was designed to guarantee highly reliable and accurate results. In particular, the engine was operated under transient conditions, along the World Harmonized Transient Cycle in cold- and hot-start conditions. The results of the test campaign clearly highlight that the lubricant formulation is a key technology for the control of particles, revealing this as an important aspect in view of the upcoming severe regulation limits on particle emissions. The experimental findings show the capability of reformulated oils to drop down the total particle number to 60–70% with respect to a baseline standard oil. The interest in the present study also lies in providing information extendable to more sustainable fuels, like hydrogen or biomethane, nowadays of great interest as alternative energy sources. [ABSTRACT FROM AUTHOR]

Raman spectroscopy is a popular technology for material identification, but it encounters difficulties when distinguishing components with closely related substances by intuition and experience. The distinction of fats and oils is a typical example, which is significant in the food industry. In this work, the Raman spectroscopy and deep learning algorithm are combined to analyze closely related animal fats (lard, butter, mutton fat and chicken fat) and vegetable oils (soybean oil and peanut oil) in a dataset. A deep neural network founded on the VGG architecture with attention mechanism is developed, reaching an accuracy of 100% for fats and oils classification. By combining Raman spectroscopy with deep learning, this research provides a potent technique for tackling the identification of similar substances. In this work, the Raman spectroscopy and deep learning algorithm are combined to analyze closely related animal fats (lard fat, butter fat, mutton fat and chicken fat) and vegetable oils (soybean oil and peanut oil) in a dataset. A deep neural network founded on the VGG architecture with attention mechanism is developed, reaching an accuracy of 100% for fats and oils classification. [ABSTRACT FROM AUTHOR]

To achieve the goal of developing high-performance lubricant additives for industrial lubrication. Herein, tetradecylphosphonic acid (TDPA) modified Ti3C2TX and graphene oxide (GO) were used as nanohybrid lubricant additives in the polyalphaolefins base oil (PAO6). The high-speed reciprocating friction and wear test shows that TDPA–Ti3C2/GO is an efficient friction-reduction and antiwear additive. The base oil mixed with 0.05 wt%TDPA–Ti3C2/0.05 wt% GO exhibits the lowest coefficient of friction (COF) and wear rate with the value of 0.09 and 4.4 × 10–6 mm3/Nm, decreased by 54.5 and 90.0% compared with pure PAO6 oil, respectively. Detailed characterization analysis shows that the tribological film of the modified TDPA–Ti3C2/GO nanohybrids oil-lubricated surface was mainly composed of PAO6, TDPA, GO, and iron oxide. This indicates that the friction-reduction and antiwear mechanism of TDPA–Ti3C2/GO in base oil lies in the adsorption of the two nanomaterials and the formation of a self-lubricating film on the rubbing interface. This study provides a new approach to the design of nanohybrid lubricant additives and creates new prospects for the application of nanomaterials in tribology. [ABSTRACT FROM AUTHOR]

This work explores experimentally the effects of DC electrical currents on lubricant film thickness alteration in lubricated sliding steel contacts in the boundary and mixed regime as measured by ultrasound. The experiments were performed in a two-electrode cell-based pin-on-disk tester instrumented with ultrasonic transducers. Unelectrified and electrified tribological tests were conducted on steel flat-on-flat contacts under various speeds and loads using both a mineral base oil and a gear oil. Film thickness, coefficient of friction (CoF), and electrical contact resistance (ECR) were measured during short experiments (30 s) in unelectrified and electrified (1.5 and 3 A) conditions. The results suggest that film thickness, CoF, and all ECR are altered by passing DC currents through the contact. In particular, film thickness increased and decreased, respectively, by applying electricity at the different speeds and loads tested. These alterations were majorly ascribed to oil viscosity decrease by local heat and surface oxidation caused by electrical discharge and break down at the interface. [ABSTRACT FROM AUTHOR]

Impact-sliding experiments were performed by using four self-made lithium-based greases, namely Yangtze Grease 1, Yangtze Grease 2, Yangtze Grease 3, and Yangtze Grease 4. The influence of base oil viscosity, thickener content, and morphology of thickener fiber clusters on the lubricating state were visually explored, combined with field-emission microscopy and two-light interference technology. The grease film distribution at the middle section was measured using Dichromatic Interference Intensity Modulation (DIIM) software. All experiments were executed in a completely flooded environment. The results show that among the components of grease, the base oil's viscosity has the greatest impact on the anti-wear performance of the grease. As the viscosity of the base oil increases, the grease exhibits better anti-wear performance. The grease film thickness under the condition of high-viscosity base oil is about 10 times higher than that under the condition of low-viscosity base oil. Secondly, the content of thickener in the grease needs to be controlled within a reasonable range. The experiments indicate that the effect of thickener content on the grease's film-forming properties becomes more pronounced at higher speeds. From the experiment using YG 4, it can be seen that a higher thickener content under high-speed conditions increases the thickness of the lubricating grease film by about 10 times. The dimensions of the thickener fibers and the density of their entanglement structure significantly influence the rheological properties and load-bearing capacity of the grease. Larger fiber sizes and higher entanglement densities result in reduced grease fluidity and recovery but enhance its load-bearing capabilities. In order to obtain the best anti-wear performance during impact-sliding motion, the size of the thickener fiber and the density of the entanglement structure need to be controlled within an appropriate range. [ABSTRACT FROM AUTHOR]

In order to improve fuel economy to meet the standard for passenger car oil, a new formulation with good viscosity–temperature performance for gasoline engine oil is required. In this study, coal-to-liquid (CTL) base oil, with a high viscosity index and good low-temperature performance, was selected as the base oil to develop the gasoline engine oil. A systematic study on the molecular interaction between the CTL base oil and the viscosity index improver (VII), including three kinds of hydrogenated styrene diene copolymers (HSD-type) and four kinds of ethylene propylene copolymers (OCP-type), was conducted. It was found that in general, in CTL base oil, the HSD-type VII exhibited a much higher viscosity index, a significantly lower shear stability index, a higher thickening ability, and a lower cold-cranking simulator (CCS) viscosity than that of OCP-type VII. Moreover, when comparing CTL base oil with mineral oil 150N, the combination of CTL base oil and the VII displayed a lower CCS viscosity than that of mineral oil, suggesting it had better low-temperature performance and was able to quickly form a protective oil film on the surface, which was beneficial for the cold start. The functional group distribution state of the VII in base oil was analyzed using synchrotron radiation micro-infrared microscope (SR Micro-IR) technology, which revealed that HSD-1 had a better molecular interaction with CTL6 than 150N because of the better uniformity of the C=C group distribution. Based on this, a SP 0W-20 gasoline engine oil was developed by the combination of CTL base oil and the HSD-1 viscosity index improver, together with an additive package, a polymethacrylate pour point depressant, and a non-silicone defoamer, which showed excellent low-temperature performance, thermal oxidation stability, and detergency performance compared to the reference oil. [ABSTRACT FROM AUTHOR]

Within electrical contacts, poor electrical conductivity of lubricants can lead to triboelectric charging, causing electrostatic currents and thermal effects, which accelerate lubrication failure. This study aimed to address these challenges by producing and testing three greases with different base oils: ionic liquid ([Oley][Oleic]), synthetic oil (PAO4), and vegetable oil-based synthetic ester (trimethylolpropane oleate). Each grease was prepared with polytetrafluoroethylene powder as the thickener. The greases were tested using a custom-made tribometer, integrated with a grounded electrical current system, with friction tests conducted with up to a 2 A electrical current flow at a constant voltage supply of 4.5 V. Under triboelectric friction testing, [Oley][Oleic] grease outperformed a commercial perfluoropolyether grease by 27.7% in friction and 16.3% in wear. This grease also showed better performance than formulated lithium grease with extreme pressure additives. The study demonstrates that greases with low interfacial resistance can retain their lubrication capacity under triboelectric conditions. These results indicate that [Oley][Oleic] grease, with its ionic liquid base oil, offers a promising solution for applications involving electrical contacts. This study highlights the potential of using advanced base oils and thickeners to enhance the performance and sustainability of lubricants in demanding environments. [ABSTRACT FROM AUTHOR]

This paper demonstrates the potential of waste turbine oil (WTBO) as a base oil to substitute for mineral oil, which is usually used in grease formulations. This study will analyze the characteristics of used turbine oil, including its chemical composition and physical characteristics, including kinematic viscosity, viscosity index, moisture content, contamination, and density. The presence of antioxidants (butylated hydroxytoluene (BHT) and amine or phenyl-a-naphthylamine (PANA), anti-wear, and corrosion-inhibiting additives that can improve the formulated lubricating grease performance and lengthen service life are just a few of the useful remaining WTBO characteristics that can be used wisely as the base oil. It is crucial to create more environmentally friendly, economically sensible, and thrifty grease formulations to adhere to Malaysia's Green Technology Master Plan, which has outlined the strategic plans for developing green technologies. The new inventions must establish a resource- and carbon- efficient economy. The abundance of WTBO in the aviation industry and the unique characteristics of WTBO itself promise a reliable supply of base oil for lubricating grease in the future. [ABSTRACT FROM AUTHOR]

This paper presents the fabrication and characterization of plane capacitors utilizing magnetodielectric materials composed of magnetizable microfibers dispersed within a silicone oil matrix. The microfibers, with a mean diameter of about 0.94 μ m, comprise hematite (α -Fe2O3), maghemite (γ -Fe2O3), and magnetite (Fe3O4). This study investigates the electrical behavior of these capacitors under the influence of an external magnetic field superimposed on a medium-frequency alternating electric field, across four distinct volume concentrations of microfibers. Electrical capacitance and resistance measurements were conducted every second over a 60-s interval, revealing significant dependencies on both the quantity of magnetizable phase and the applied magnetic flux density. Furthermore, the temporal stability of the capacitors' characteristics is demonstrated. The obtained data are analyzed to determine the electrical conductance and susceptance of the capacitors, elucidating their sensitivity to variations in microfiber concentration and magnetic field strength. To provide theoretical insight into the observed phenomena, a model based on dipolar approximations is proposed. This model effectively explains the underlying physical mechanisms governing the electrical properties of the capacitors. These findings offer valuable insights into the design and optimization of magnetodielectric-based capacitors for diverse applications in microelectronics and sensor technologies. [ABSTRACT FROM AUTHOR]

ABSTRACT 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]

Beam pumping is currently the broadly used method for oil extraction worldwide. A pumpjack shutdown can be incurred by failures from the load, corrosion, work intensity, and downhole working environment. In this study, the duration of uninterrupted pumpjack operation is defined as the pump inspection cycle. Accurate prediction of the pump inspection cycle can extend the lifespan, reduce unexpected pump accidents, and significantly enhance the production efficiency of the pumpjack. To enhance the prediction performance, this study proposes an improved two-layer stacking ensemble model, which combines the power of the random forests, light gradient boosting machine, support vector regression, and Adaptive Boosting approaches, for predicting the pump inspection cycle. A big pump-related oilfield data set is used to demonstrate the proposed two-layer stacking ensemble model can significantly enhance the prediction quality of the pump inspection cycle. [ABSTRACT FROM AUTHOR]

The paper presents a technology for producing base oil by oxidizing organosulfur compounds, contained in petroleum distillates and deasphaltisates, with hydrogen peroxide in the presence of vegetable (rapeseed and castor) oils, followed by extraction of oxidates and dewaxing of raffinates. Extraction of the resulting oxidized mixture (oxidate) was carried out with N-methylpyrrolidone. The content of rapeseed oil contained in the raffinate and extract was determined. The extract solution from a medium-viscosity oil distillate was cooled to obtain a secondary raffinate represented by a sulfoxide concentrate. The secondary raffinate was used as a base oil for producing a lubricant with high tribological properties for use in heavily loaded friction units. The rapeseed oil remained in the raffinate improves its viscosity index and lubricating properties. The raw materials and obtained raffinates were analyzed to assess their physicochemical and tribological properties. [ABSTRACT FROM AUTHOR]

The concept of volume fracturing has revolutionized the conventional limits of low permeability, expanded the effective resource space, and significantly enhanced oil well production in tight oil reservoir development. This paper elucidates the mechanism of volume fracturing technology for tight sandstone reservoirs by considering multiple factors such as the initiation range of multi-fractures, influence of far-well horizontal principal stress on fracture initiation and propagation, degree of natural fractures development, and mechanical parameters of reservoir rock. Through simulation based on the mechanical parameters of reservoir rock, a comparative analysis was conducted between the model-calculated rock fracture pressure value and measured data from fracturing construction wells in the study area. The results revealed that there was a discrepancy within 10% between the model calculations and actual data. By simulating the effects of different injection volumes of fracturing fluid, pumping rates, and perforation methods on the fracture geometry, optimal design parameters for volume fracturing technology were obtained. Additionally, we propose optimization ideas and suggestions for construction parameters applicable to field operations. The simulation results indicate that a minimum recommended fluid volume scale exceeding 1800 m3 is advised for the reservoir. Based on frictional calculations, it is recommended to have an on-site construction rate not less than 18.0 m3/min along with 36–48 holes/section for perforation purposes. The numerical simulation research presented in this paper provides a theoretical reference basis and practical guidance for the application of fracturing network technology in tight sandstone reservoirs. [ABSTRACT FROM AUTHOR]

Summary: In this study, the effects of citric acid‐loaded Hβ zeolite (F), activated clay and their modified decolorizers on the nutrients, volatile compounds and harmful substances of sesame oil in the decolorization process were evaluated. The results showed that the decolorization effect of F was second only to that of activated clay, the yield of F‐treated sesame oil sample was not significantly different from that of other decolorizers. The formation of asarinin was detected only in the sesame oil samples treated with F and H (zinc chloride‐activated clay). Compared with the activated clay‐treated sesame oil samples, the retention of tocopherols in the F‐treated sesame oil sample was significantly increased by 23.11%, and the retention of phytosterols was increased by 4.85%. The removal rate of the harmful substances Norharman and Harman in the F‐treated sesame oil sample was 96.79%, which was second only to that of the activated clay. Additionally, the removal rate of the total volatile compounds was the highest at 69.47%. The effects of different decolorizers on the sesame oil samples were closely related to the specific surface area, pore size and surface acidic sites of these decolorizers. This study could provide ideas for the industrial application of leached sesame oil, such as cosmetics and base oils. [ABSTRACT FROM AUTHOR]

This work is focused on the thermophysical and tribological study of eight nanolubricant compositions based on a polyalphaolefin (PAO 20) and two different nanoadditives: multi-walled carbon nanotubes (MWCNTs) and hexagonal boron nitride (h-BN). Regarding the thermophysical properties, density and dynamic viscosity of the base oil and the nanolubricants were measured in the range of 278.15–373.15 K, as well as their viscosity index, with the aim of evaluating the variation of these properties with the addition of the nanoadditives. On the other hand, their lubricant properties, such as contact angle, coefficient of friction, and wear surface, were determined to analyze the influence of the nanoadditives on the tribological performance of the base oil. The results showed that MWCNTs and h-BN nanoadditives improved the wear area by 29% and 37%, respectively, at a 0.05 wt% concentration. The density and dynamic viscosity increased compared with the base oil as the nanoadditive concentration increased. The addition of MWCNTs and h-BN nanoparticles enhanced the tribological properties of PAO 20 base oil. [ABSTRACT FROM AUTHOR]

Geochemical analysis was performed on the Cretaceous sequence of the Azhar‐A‐2 well in the West Beni Suef Basin (WBSB), Western Desert, Egypt, utilizing data on total organic carbon (TOC), kerogen composition, vitrinite reflectance (Ro%) and Rock‐Eval pyrolysis. In addition, a 1D basin model was built to investigate the burial and temperature history of the study area. The most important Cretaceous source rocks are predominantly reported within the Albian Kharita Formation and Late Cenomanian‐Santonian Abu Roash (AR) Formation. Based on visual kerogen tests and Rock‐Eval pyrolysis, AR Formation (A, E, F, and G) are mixed oil‐ and gas‐prone source rocks with kerogens ranging from type II to type III, where A/R 'A and F' Members show dominant oil‐prone kerogen with the highest generative potential, while A/R 'E and G' Members are more gas‐prone kerogen. Most samples of the lower Kh Formation were interpreted as gas‐prone kerogen type III with low generative potential. On the other hand, the high amount of liptinite in the visual kerogen macerals is a strong indicator that the lower Petroleum Formation is an oil‐prone rather than gas‐prone source rock. The thermal maturity of the studied members increases consistently with depth, ranging from immature at the top of the AR Formation to the main/peak oil window at the base of the Lower Kharita Formation, which served as an active source rock for the hydrocarbons generated in the WBSB. The high value of the heat flow in the Beni Suef Basin (57 and 60 mW/m2) is a good indicator for the shallowing of the active source rock depth limit depth. From the study of the basin modeling, the main mature zone reached between 9811 and 11,090 ft in the middle of the Late Cretaceous (84.3–82.5 Ma) is through the L. Kharita Formation with three phases of hydrocarbon generation according to transformation ratio, where the second phase is the main stage in which TR is 5%–50%, showing the beginning of oil expulsion (Ro: 0.73%–0.78%, possibly 0.81%). [ABSTRACT FROM AUTHOR]

Purpose: This study aims to prepare thymol-based deep eutectic solvents (DESs) and use them as lubricates for friction and wear tests to simulate the wear conditions of hybrid bearings. Design/methodology/approach: Through the characterization and analysis of the morphology of wear scars and the elemental composition of friction films, the tribological behavior and wear mechanism of sample materials as lubricants were investigated and the anti-wear mechanism of thymol-based DESs was discussed. Findings: The findings demonstrate that because of the formation of a fluid lubrication film and excellent kinematic viscosity, the lubrication effect of the prepared DES is improved by about 50% compared to the base lubricating oil. The prepared [Ch]Cl-thymol DES has a better anti-friction and lubrication effect than citric-thymol, EG-thymol and urea-thymol DESs, with an average friction coefficient of about 0.04. Originality/value: In this work, the friction reduction properties of thymol-based DESs were studied as lubricants for the first time, and the lubrication mechanism of sample materials was investigated. [ABSTRACT FROM AUTHOR]

With the continuous advancement of industrial technology, higher demands have been placed on the properties of gear oils, such as oxidation stability and shear resistance. Herein, the oxidation stability of high-viscosity metallocene poly- α -olefins (mPAOs) was improved by chemical modification via aromatic amine alkylation. The modified mPAO base oils were synthesized separately with diphenylamine (mPAO-DPA) and N-phenyl- α -naphthylamine (mPAO-NPA), and their applicability in industrial gear oil formulations was evaluated. The composition and physicochemical properties of the obtained samples were assessed using 1H NMR spectroscopy, Fourier transform infrared spectroscopy, gel permeation chromatography, and the American Society for Testing and Materials standards (ASTM D445, ASTM D2270, ASTM D92, etc.) confirming the successful completion of the alkylation reaction. The oxidation stability of the samples was also evaluated using pressurized differential scanning calorimetry. The initial oxidation temperature of mPAO-NPA (230 °C) was 53 °C higher than that of mPAO, and the oxidation induction period of mPAO-DPA was nearly twice that of mPAO-NPA. Thermogravimetric analysis in air revealed the increased thermal decomposition temperature and improved thermal stability of modified mPAO. ISO VG 320 industrial gear oils were formulated using mPAO alkylated with N-phenyl- α -naphthylamine(Lub-2) and commercially purchased PAO100 (Lub-1) as base oil components. The antioxidant performance of two industrial gear oils was evaluated through oven oxidation and rotating oxygen bomb tests. The oxidation induction period of Lub-2 was 30% higher than that of Lub-1, with the latter having a lower acid number and a smaller increase in viscosity at 40 °C. Finally, the friction performance of the samples was assessed on a four-ball friction tester, revealing the synergistic effect of the mPAO-NPA base oil with the HiTEC 3339 additive, forming a more stable oil film with a smaller wear scar diameter. [ABSTRACT FROM AUTHOR]

Rhododendron ponticum (L.) is a highly invasive, non-native woody shrub that prevents tree regeneration and kills native flora. Achieving successful control of rhododendron can be difficult due to its thick waxy leaf surfaces, which discourage the absorption of foliar-applied herbicides. The spray adjuvant Mixture B NF® has therefore been used for many years to improve the efficacy, absorption, and rainfastness of foliar applications of glyphosate. We established an experiment to test if alternative non-hazardous adjuvants could be equally effective. Treatments were applied as foliar sprays and then subjected to artificial rainfall to examine rainfastness. We found that the non-hazardous adjuvants Codacide Oil® and Toil® (both based on rapeseed oil), and also SU Wett®, offered little or no benefit to the efficacy or rainfastness of glyphosate applications to rhododendron. However, further research using these adjuvants on other weed species is recommended. The only treatment in our study that showed acceptable levels of rhododendron control was glyphosate plus Mixture B NF®. Current recommendations for the control of rhododendron are therefore still valid. When foliar sprays of rhododendron bushes are required, apply 2.88–3.60 kg a.i. ha− 1 glyphosate and add Mixture B NF® adjuvant at a rate of 2 per cent of final spray volume. A minimum rain-free period of 6 h should occur after application of glyphosate products to any weed type, but if there is a risk of rainfall occurring earlier than this, and the application cannot be delayed, the use of Mixture B NF® is likely to improve rainfastness, reduce run-off and improve control. [ABSTRACT FROM AUTHOR]

In the current era of widespread antimicrobial resistance, the utilization of essential oils (EOs) derived from plants has emerged as a promising alternative in combating pathogens that have developed resistance to antibiotics. This review explores the therapeutic potential of essential oils as valuable tools in restoring the efficacy of antibiotics, highlighting their unique ability to affect bacteria in multiple ways and target various cellular systems. Despite the challenge of elucidating their precise mode of action, EOs have shown remarkable results in rigorous testing against a diverse range of bacteria. This review explores the multifaceted role of EOs in combating bacterial microorganisms, emphasizing their extraction methods, mechanisms of action, and comparative efficacy against synthetic antibiotics. Key findings underscore the unique strategies EOs deploy to counter bacteria, highlighting significant differences from conventional antibiotics. The review extends to advanced coating solutions for medical devices, exploring the integration of EO formulations into these coatings. Challenges in developing effective EO coatings are addressed, along with various innovative approaches for their implementation. An evaluation of these EO coatings reveals their potential as formidable alternatives to traditional antibacterial agents in medical device applications. This renaissance in exploring natural remedies emphasizes the need to combine traditional wisdom with modern scientific advancements to address the urgent need for effective antimicrobial solutions in the post-antibiotic era. [ABSTRACT FROM AUTHOR]

Instead of applying the commonly used parametric Almon or Beta lag distribution of MIDAS, Breitung and Roling (J Forecast 34:588–603, 2015) suggested a nonparametric smoothed least-squares shrinkage estimator (henceforth SLS 1 ) for estimating mixed-frequency models. This SLS 1 approach ensures a flexible smooth trending lag distribution. However, even if the biasing parameter in SLS 1 solves the overparameterization problem, the cost is a decreased goodness-of-fit. Therefore, we suggest a modification of this shrinkage regression into a two-parameter smoothed least-squares estimator ( SLS 2 ). This estimator solves the overparameterization problem, and it has superior properties since it ensures that the orthogonality assumption between residuals and the predicted dependent variable holds, which leads to an increased goodness-of-fit. Our theoretical comparisons, supported by simulations, demonstrate that the increase in goodness-of-fit of the proposed two-parameter estimator also leads to a decrease in the mean square error of SLS 2 , compared to that of SLS 1 . Empirical results, where the inflation rate is forecasted based on the oil returns, demonstrate that our proposed SLS 2 estimator for mixed-frequency models provides better estimates in terms of decreased MSE and improved R2, which in turn leads to better forecasts. [ABSTRACT FROM AUTHOR]

The work is devoted to the study of the influence of nitrogenous bases on the composition of oil and the structure of asphaltenes on their colloidal stability in solution. Model petroleum systems with a basic nitrogen content of 1, 2, and 3% wt. were used as objects of study. Asphaltene-like nitrogenous bases were obtained by thermolysis of model petroleum systems with different nitrogen contents. The results were obtained using elemental analysis, non-aqueous potentiometric titration, spectrophotometry, 1H NMR spectroscopy, and liquid adsorption chromatography. It was established that the content of Nbas in asphaltenes increases by 0.3–1.3% wt. with the increase in quinoline content in petroleum components. Quinoline is incorporated into the supramolecular structure of asphaltenes and increases their average molecular weight by 650 amu. and aromaticity by 2%. The aggregative stability of asphaltenes decreases by 1.5–6 times with an increase in their average molecular weight and an increase in Nbas in their composition as a component of a dispersion medium. The colloidal stability of synthetic asphaltene-like substances, on the contrary, is due to the appearance of their molecular sequence of fragments containing Nbas in aromatic rings. [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]

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]

Estuaries are nutrient-rich environments characterized by a gradient in salinity due to the mixing of freshwater and seawater. These bodies of water play vital functions in nature and provide a wide variety of essential ecosystem services. In general, many natural and/or man-made activities have strongly stressed the Egyptian Nile estuarine habitats, as has the water shortage that was expected after the construction of the Grand Ethiopian Renaissance Dam. In recent decades, the Nile Delta has been considered to be one of the most important productive oil-producing petroleum regions due to onshore and offshore gas discoveries alongside gasoline and base oil generation. Up-to-date systematic reviews of the Egyptian estuarine habitats (Rosetta and Damietta) are missing, and the review reported here was undertaken to fill this gap. In this review, we consider the physical, chemical, geological, pollution, and biological parameters of Egyptian Nile estuaries. In this context, our aim is to contribute to a broader understanding of the Egyptian estuarine habitat; moreover, we provide potential warning signals that may aid in estuarine environmental protection. We found that most of the previous studies had focused on the two branches of the Nile or on the marine waters adjacent to these branches, and that only a few studies focused on the estuarine habitats themselves. In most of these previous studies, the salinity gradient of water was reported to be a significant factor in the distribution of the different measured parameters while, in contrast, more recent investigations confirm the importance of potential effluent sources in affecting the distribution of these parameters. We highly recommend that the data reported here be updated in future studies on different environmental aspects. [ABSTRACT FROM AUTHOR]

Machine learning models that are used for the prediction and control of production can improve quality and yield. However, developing models that are highly accurate and reflective of real-world processes is challenging. We propose a feedforward neural network model specifically designed for continuous Multistage Manufacturing Processes (MMPs) without intermediate outputs. This model, which is termed "MMP Net," can accurately represent the control mechanism of continuous MMPs. Whereas existing studies on learning MMPs assume an intermediate output data, the MMP Net does not require such an unrealistic assumption. We use the MMP Net to develop prediction models for the lubricant base oil production process of a world-leading lubricant manufacturer. Evaluation results show that the MMP Net is superior to other deep neural network and machine learning models. Consequently, the MMP Net was actually implemented in a real factory in 2022 and is expected to save 900,000 dollars per year for each production line. We believe that our work can serve as a basis to develop customized machine learning solutions for improving continuous MMPs. [ABSTRACT FROM AUTHOR]

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]

Solid lipid nanoparticles (SLNs) represent promising nanostructures for drug delivery systems. This study successfully synthesized SLNs containing different proportions of babassu oil (BBS) and copaiba oleoresin (COPA) via the emulsification–ultrasonication method. Before SLN synthesis, the identification and quantification of methyl esters, such as lauric acid and β-caryophyllene, were performed via GC-MS analysis. These methyl esters were used as chemical markers and assisted in encapsulation efficiency experiments. A 22 factorial design with a center point was employed to assess the impact of stearic acid and Tween 80 on particle hydrodynamic diameter (HD) and polydispersity index (PDI). Additionally, the effects of temperature (8 ± 0.5 °C and 25 ± 1.0 °C) and time (0, 7, 15, 30, 40, and 60 days) on HD and PDI values were investigated. Zeta potential (ZP) measurements were utilized to evaluate nanoparticle stability, while transmission electron microscopy provided insights into the morphology and nanometric dimensions of the SLNs. The in vitro cytotoxic activity of the SLNs (10 µg/mL, 30 µg/mL, 40 µg/mL, and 80 µg/mL) was evaluated using the MTT assay with PC-3 and DU-145 prostate cancer cell lines. Results demonstrated that SLNs containing BBS and COPA in a 1:1 ratio exhibited a promising cytotoxic effect against prostate cancer cells, with a percentage of viable cells of 68.5% for PC-3 at a concentration of 30 µg/mL and 48% for DU-145 at a concentration of 80 µg/mL. These findings underscore the potential therapeutic applications of SLNs loaded with BBS and COPA for prostate cancer treatment. [ABSTRACT FROM AUTHOR]

This study reports the separation of oil from water using cellulose acetate (CA) ultrafiltration (UF) membranes. The CA membranes were fabricated by varying bath temperatures such as 5 ± 2°C, 25 ± 2°C and 45 ± 2°C using the phase inversion technique and assess their performance based on the oil removal efficiency. Changing the coagulation bath temperature (CBT) at that stage of membrane formations affects the porosity, pore size, hydraulic resistance, morphological structure and performance of membranes. The obtained results revealed increased porosity and pore size and also decreased hydraulic resistance of the membranes as the CBT increases. Field Emission Scanning Electron Microscopy (FESEM) images indicate that a large number of surface pores are visibly found at the higher bath temperature. Atomic force Microscopy (AFM) images show increased average roughness (Ra) of the membrane as the CBT of the membrane increases. The water flux and permeate flux of all the membranes tend to increase with an increase in CBT. From Chemical Oxygen Demand (COD) studies, the oil removal efficiency was maximum for the lower bath temperature membrane. The results indicate that conditions of the coagulation bath significantly affect the porous structure, morphology and performance of the membrane. [ABSTRACT FROM AUTHOR]

The cast thin sections of tight oil reservoirs contain important parameters such as rock mineral composition and content, porosity, permeability and stratigraphic characteristics, which are of great significance for reservoir evaluation. The use of deep learning technology for intelligent identification of thin section images is a development trend of mineral identification. However, the difficulty of making cast thin sections, the complexity of the making process and the high cost of thin section annotation have led to a lack of cast thin section images, which cannot meet the training requirements of deep learning image recognition models. In order to increase the sample size and improve the training effect of deep learning model, we proposed a generation and annotation method of thin section images of tight oil reservoir based on deep learning, by taking Fuyu reservoir in Sanzhao Sag as the target area. Firstly, the Augmentor strategy space was used to preliminarily augment the original images while preserving the original image features to meet the requirements of the model. Secondly, the category attention mechanism was added to the original StyleGAN network to avoid the influence of the uneven number of components in thin sections on the quality of the generated images. Then, the SALM annotation module was designed to achieve semi-automatic annotation of the generated images. Finally, experiments on image sharpness, distortion, standard accuracy and annotation efficiency were designed to verify the advantages of the method in image quality and annotation efficiency. [ABSTRACT FROM AUTHOR]

We propose a genetic algorithm for optimizing oil skimmer assignments, introducing a tailored repair operation for constrained assignments. Methods essentially involve simulation-based evaluation to ensure adherence to South Korea's regulations. Results show that the optimized assignments, compared to current ones, reduced work time on average and led to a significant reduction in total skimmer capacity. Additionally, we present a deep neural network-based surrogate model, greatly enhancing efficiency compared to simulation-based optimization. Addressing inefficiencies in mobilizing locations that store oil skimmers, further optimization aimed to minimize mobilized locations and was validated through scenario-based simulations resembling actual situations. Based on major oil spills in South Korea, this strategy significantly reduced work time and required locations. These findings demonstrate the effectiveness of the proposed genetic algorithm and mobilized location minimization strategy in enhancing oil spill response operations. [ABSTRACT FROM AUTHOR]

Potent synthetic drugs, as well as biomolecules extracted from plants, have been investigated for their selectivity toward cancer cells. The main limitation in cancer treatment is the ability to bring such molecules within each single cancer cell, which requires accumulation in the peritumoral region followed by homogeneous spreading within the entire tissue. In the last decades, nanotechnology has emerged as a powerful tool due to its ability to protect the drug during blood circulation and allow enhanced accumulation around the leaky regions of the tumor vasculature. However, the ideal size for accumulation of around 100 nm is too large for effective penetration into the dense collagen matrix. Therefore, we propose a multistage system based on graphene oxide nanosheet-based quantum dots (GOQDs) with dimensions that are 12 nm, functionalized with hyaluronic acid (GOQDs-HA), and deposited using the layer-by-layer technique onto an oil-in-water nanoemulsion (O/W NE) template that is around 100 nm in size, previously stabilized by a biodegradable polymer, chitosan. The choice of a biodegradable core for the nanocarrier is to degrade once inside the tumor, thus promoting the release of smaller compounds, GOQDs-HA, carrying the adsorbed anticancer compound, which in this work is represented by curcumin as a model bioactive anticancer molecule. Additionally, modification with HA aims to promote active targeting of stromal and cancer cells. Cell uptake experiments and preliminary penetration experiments in three-dimensional microtissues were performed to assess the proposed multistage nanocarrier. [ABSTRACT FROM AUTHOR]

Given the role that pipelines play in transporting crude oil, which is considered the basis of the global economy and across different environments, hundreds of studies revolve around providing the necessary protection for it. Various technologies have been employed in this pursuit, differing in terms of cost, reliability, and efficiency, among other factors. Computer vision has emerged as a prominent technique in this field, albeit requiring a robust image-processing algorithm for spill detection. This study employs image segmentation techniques to enable the computer to interpret visual information and images effectively. The research focuses on detecting spills in oil pipes caused by leakage, utilizing images captured by a drone equipped with a Raspberry Pi and Pi camera. These images, along with their global positioning system (GPS) location, are transmitted to the base station using the message queuing telemetry transport Internet of Things (MQTT IoT) protocol. At the base station, deep learning techniques, specifically Holistically-Nested Edge Detection (HED) and extreme inception (Xception) networks, are employed for image processing to identify contours. The proposed algorithm can detect multiple contours in the images. To pinpoint a contour with a black color, representative of an oil spill, the CIELAB color space (LAB) algorithm effectively removes shadow effects. If a contour is detected, its area and perimeter are calculated to determine whether it exceeds a certain threshold. The effectiveness of the proposed system was tested on Iraqi oil pipeline systems, demonstrating its capability to detect spills of different sizes. [ABSTRACT FROM AUTHOR]