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Owing to their low flexibility, poor processability and a lack of responsiveness, inorganic materials are usually non-ideal for constructing a living organism. Hence, to date, lifelike materials with structural hierarchies and adaptive properties usually rely on light and soft organic molecules, although few exceptions have been acquired using two-dimensional (2D) inorganic nanosheets. Herein, with a systematic study on the gelation behavior of carbon-based 0D quantum dots, 1D nanotubes, and 3D fullerenes, we find that acidified 1D carbon nanotubes (CNTs) can serve as an alternative building block for fabricating purely inorganic biomimetic soft materials. The as-prepared CNT gels exhibit not only a pH- or photothermal-triggered mechanical and tribological adaptivity, which allows them to simulate the behavior of sea cucumbers, peacock mantis shrimps, and mammalian muscles or cortical bones, but also a unique damping property that is similar to spider's cuticular pad. Their high elasticity, effective lubrication, excellent biocompatibility, and controllable friction and wear also allow them to function as a new type of smart lubricants, whose tribological properties can be regulated either by its internal pH changes or spatiotemporally by near-infrared (NIR) light irradiations, free of any toxic and flammable base oils or additives. [ABSTRACT FROM AUTHOR]

The adsorption of methylene blue dye on modified mesoporous silica based on palm oil boiler ash (MS-POBA) as an adsorbent with a methyl ester sulfonate (MES) was investigated. MSPOBA and MES as a template improved the adsorption capacity of methylene blue by increasing the pore size of boiler ash silica. The characteristics of the material were determined using FTIR, XRD, BET, and SEM-EDX analyzers. The adsorption of methylene blue on the MS-POBA adsorbent was determined using a UV-Vis spectrophotometer. The MES as a template pasted to MS-POBA, could be increased surface area, pore diameter, and volume. In optimized conditions, pH, the adsorbent mass, the adsorption time, the methylene blue concentration, the adsorption capacity, and recovery were obtained at 7.0, 0.03 g, 45 minutes, 20 mg L-1, 15.578 mg g-1, and 96.9%, respectively. The adsorption of methylene blue on boiler ash silica with an MES template follows the pseudo-second-order kinetic model with a value of R² = 0.999 and Langmuir isotherm adsorption model. [ABSTRACT FROM AUTHOR]

Background: Topical delivery of medication is often considered to be the best choice due to benefits such as avoidance of gastric degradation, first pass metabolism along with effortless application and retrieval. In topical delivery, the types of the vehicles and the physicochemical characteristics of drug are the prime variables that control the drug release and the therapeutic efficacy. The main component of Boswellia, Boswellic Acid (BA), is assumed to be accountable for the majority of pharmacologic effects. Nanoemulgel combines the benefits of nano-emulsions and the gels. Materials and Methods: The present work carried out with an objective of formulation of topical nanoemulgel of boswellic acid containing carbopol 934 and liquid paraffin as oil base. Results: The prepared nanoemulgel characterized for the various parameters such as, in vitro, ex vivo permeation and in vivo anti-inflammatory activity. The optimized nanoemulsion consisted of carbopol 934 and surfactant mix ratio (tween 80:Span20::1:1), in 1, 1.5 and 2 % w/w. The in vitro, ex vivo permeation of BA from nanoemulgel were found to be 90±0.33% and 85.5±1.2% at 12 hr respectively. Conclusion: Topical application of BA nanoemulgel formulation significantly reduced the inflammation by reducing the serum IL-6 concentration compared with the arthritic rats. The research findings showed that BA nanoemulgel has the ability to increase penetration through the skin and produce an anti-inflammatory impact. [ABSTRACT FROM AUTHOR]

The volatile and olfactory profiles of three Portuguese olive oils with protected designations of origin (PDO) were studied: "Azeite do Alentejo Interior", "Azeites da Beira Interior", and "Azeite de Trás-os-Montes". Seven classes of volatiles were identified, with aldehydes, followed by hydrocarbons and alcohols, the most prevalent (5.63, 2.92, and 2.79 mg/kg olive oil, respectively). The "Azeites da Beira Interior" oils exhibited the highest amount of volatiles (18.2 ± 4.6 mg/kg olive oil) compared to the oils from the other two PDOs. Ten positive olfactory sensations were detected, and a significant effect of the PDO on the intensities of fruity, apple, cabbage, tomato, dry and fresh herbs was observed. Specifically, "Azeite do Alentejo Interior" PDO oils were characterized as fruity-ripe, while "Azeite de Trás-os-Montes" PDO oils were labelled as fruity-green. Conversely, "Azeites da Beira Interior" PDO oils encompassed both fruity-ripe and fruity-green oils. Unique volatile and olfactory fingerprints were established for each PDO, allowing the linear discrimination of the oils according to the PDO, with a predictive sensitivity of 98.0 ± 4.2% (repeated K-fold-CV). Furthermore, a lab-made electronic nose successfully discriminated the studied oils based on the PDO, with a predictive accuracy of 99.7 ± 2.0% (repeated K-fold-CV). This device also allowed predicting the concentrations of the three main volatile classes found in the oils through multiple linear regression models (R2 ≥ 0.923 ± 0.101 and RMSE ≤ 1.32 ± 0.72 mg/kg oil; repeated K-fold-CV). These findings underscore the potential of the electronic nose as a reliable traceability tool to authenticate the PDO declaration of Portuguese olive oils, and broaden its use beyond non-PDO oils from a specific geographical area to encompass a national scale. [ABSTRACT FROM AUTHOR]

Emollients are valued ingredients of many cosmetic products and medical devices used to support the treatment and prevention of many skin diseases. Despite the fact that they are one of the oldest cosmetic ingredients, raw materials as well as new recipe solutions are constantly being sought, the main goal of which is to obtain products with the most favorable physicochemical properties while improving the hydration of the stratum corneum and softening and smoothing the skin. It should be noted that there are few scientific articles on the effect of emollients on the physicochemical and usable properties of emollient preparations of the body-oils type. The obtained formulations were subjected to physicochemical tests (dynamic viscosity, surface tension, contact angle, and color evaluation), and the degree of skin hydration and lubrication after application of the developed cosmetic oils was evaluated. Cosmetic oils based on natural emollients were characterized by weaker spreading abilities, which was confirmed by their higher viscosity, surface tension, and contact-angle results relative to those obtained for cosmetic oils based on synthetic emollients. In addition, it was found that the use of both groups of cosmetic oils based on natural and synthetic emollients leads to an increase in the degree of hydration of the skin and an increase in its oiliness. However, a higher increase in the degree of hydration and a lower decrease in the level of skin lubrication are observed after the application of body oils based on natural emollients. [ABSTRACT FROM AUTHOR]

Ageing skin & wrinkles on the face are two unwelcome consequences of sun exposure and ultraviolet radiation. There is a very high concentration of active components in serum, and its deep formula allows it to penetrate the deepest layers of skin. A non-greasy finish and rapid absorption characterise the essential oil-based product. It was with these characteristics in mind that the team set out to formulate a serum using combination of herbal extract. The antimicrobial characteristics of Ocimum sanctum, Eucalyptus globulus labill and Lavandula angustifolia are incorporated into a highly concentrated cosmetic product known as face serum. The purpose of this research was to examine the physicochemical and antibacterial characteristics of a facial serum formulated using essential oils. In light of the serum's effects on the skin, its components were studied chemically and in particular for their Ocimum sanctum, Eucalyptus globulus labill, etc. Clinical trials on human skin have demonstrated that the active chemicals in face serum can alleviate a variety of skin conditions. Because it contains olive oil and glycerine it has a pleasant cleansing effect on the skin and is easily spreadable, according to the study. Citrus bergamia oil, which is also used in Risso et Poiteau face serum, has shown promising results in combating acne. The facial serum underwent a battery of tests to determine its quality, including microbiological analysis, physical characteristics, pH, spreadability, and viscosity. The stability investigation's findings demonstrate that neither visual acuity nor homogeneity changed. Consequently, the greatest choice for maintaining healthy skin may be this antiacne serum. [ABSTRACT FROM AUTHOR]

Based on the oil and gas component data of an offshore gas field in West Africa, the steady‐state models of the triethylene glycol (TEG) dehydration process and the low‐temperature separation dehydration process are established. The adaptability of two kinds of processes to the disturbance of pressure, temperature, and flow of imported natural gas source is studied, and the sensitivity analysis is carried out. In addition, the investment cost and operating cost of the two types of processes are compared. The low temperature separation dehydration process is more adaptable to the disturbance of inlet gas source than the TEG dehydration process. The former is more expensive to build than the latter, but less expensive to run. The low temperature separation dehydration is preferred as the natural gas dehydration process which is more suitable for floating production storage and offloading. [ABSTRACT FROM AUTHOR]

Vegetable oils are a highly promising alternative to produce various lubricants, owing to their biodegradability and eco-friendliness. In comparison to mineral oil, these oils possess a higher flash point and viscosity index, along with superior lubricating properties. Additionally, most of the vegetable oils are easily accessible in local markets in India. However, their industrial application is limited by poor thermal and oxidative stability, which can be addressed through chemical modification, the addition of appropriate additives, or by blending these oils. Greases, characterized by their semi-solid consistency, are widely used lubricants. Most of the grease production is based on mineral oils as base oil and lithium soap as a thickener. These materials are not only non-biodegradable but also scarce and have health implications. Consequently, biodegradable grease represents an eco-friendly and healthy alternative. Grease made using vegetable oils with the required properties has the potential to bring about revolutionary changes. The present work focuses on the feasibility of using chemically modified blended rice bran oil (RBO) and Calophyllum inophyllum oil (CIO) as a bio-lubricant. The oils undergo a two-step modification process, involving a transesterification reaction followed by epoxidation. Significant improvements have been observed in the chemical properties (acid, peroxide, and iodine values) of transesterified epoxidized rice bran oil Calophyllum inophyllum oil mixture–50:50 (ETRCIO) when compared with Unmodified Rice bran oil Calophyllum inophyllum oil mixture–50:50 (RCIO). The acid value, peroxide value, and iodine value improved by 91.66%, 87.08%, and 15.78% respectively. The rheological, tribological, and chemical properties of the blended samples have been evaluated and compared to pure oils using American Society for Testing and Materials (ASTM) and Indian Standards (IS). Additionally, ETRCIO was used to develop a bio-grease, and its tribological properties were extensively analyzed. The mean coefficient of friction (COF) and wear scar diameter (WSD) of the ETRCIO grease sample improved by 10.20% and 29.32% respectively when compared with that of commercially available grease. These findings indicate that the ETRCIO bio-grease exhibits superior tribological properties in comparison to commercially available grease. Research highlights: • The study explores the potential of vegetable oils as a biodegradable and environmentally friendly alternative for producing lubricants, specifically focusing on rice bran oil and Calophyllum inophyllum oil. • The oils undergo a two-step chemical modification process (transesterification followed by epoxidation) to improve their thermal and oxidative stability, making them suitable for industrial use. • The chemically modified and blended oils showed significantly improved chemical properties. • The rheological, tribological, and chemical properties of the blended samples were evaluated according to ASTM, and IS standards and compared with those of pure oils. • A bio-grease was formulated using these chemically modified oils, exhibiting better tribological properties than commercially available grease, indicating its potential as an eco-friendly and health-conscious alternative to traditional mineral oil-based greases. [ABSTRACT FROM AUTHOR]

It needs to be improved the conversion efficiency and stable operation of conventional pyrolysis with high-temperature flue gas heating (HFH). Herein, a new radiative heating (RH) pyrolysis method is proposed. Experimental studies are carried out on a self-made radiation pyrolysis pilot plant to investigate the effects of different factors (pyrolysis final temperature, residence time, and carrier gas volume) on product distribution. The results show that with the increase of pyrolysis temperature, the yield of the gas phase consistently increases, and the proportion of CH4 and H2 in the pyrolysis gas reaches 62.31% at 700 °C. The yield of the liquid phase increases and then decreases. The recovery rate of pyrolysis oil achieves 68.07% when the pyrolysis temperature is 600 °C with main components of ketones and unsaturated hydrocarbon compounds. The yield of the solid phase consistently decreases. The RH in this work generates more pyrolysis gas in the pyrolysis process and alleviates the effects of fouling layers on the continuous operation of the equipment which has guiding significance for the efficient resource utilization of oil sludge. [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]

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]

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]

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]

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]

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]

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]

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]

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]

Efficient machinery operation relies on the performance of high-quality lubricants. Currently, mineral oils of different grades are widely employed for lubricating machine components, but their environmental impact is a concern. Biolubricants are potential alternatives to mineral oils due to environmental factors. The present study focuses on assessing the rheological characteristics of SiO2 nanoparticle (NP)-enhanced ecofriendly biolubricants for near zero and high-temperature conditions. Pure neem oil, pure castor oil and a 50:50 blend of both oils were considered as the base oils. Nanobiolubricants with enhanced dispersion stability were prepared for varied concentrations of NPs using an ultrasonification method. Viscosity analysis was conducted using an MCR-92 rheometer, employing the Herschel Bulkley model to precisely characterize the viscosity behavior of bio-oils. Due to the fluid–solid interaction between SiO2 NPs and bio-oils, a crossover trend was observed in the flow curves generated for different base oils enriched with SiO2 NPs. For neem oil, a significant increase in viscosity was noted for 0.2 wt% of NPs. Using the multilayer perceptron (MLP) algorithm, an artificial neural network (ANN) model was developed to accurately predict the viscosity variations in nanobiolubricants. The accuracy of the predicted values was affirmed through experimental investigations at the considered nanoSiO2 weight concentrations. [ABSTRACT FROM AUTHOR]

Different carbon-based nanomaterials (fullerenes, graphene, SWCNTs, and SWCNT-COOH) were tested as additives in a base mineral oil, SN150; rapeseed oil (RSO); and a 50/50 by volume blend of the two using an HFRR (high-frequency reciprocating rig) tester for coefficient of friction (COF) and wear scar diameter (WSD) determinations and a four-ball tester for welding point determinations. The concentrations considered for the HFRR tests were 0.1, 0.5, 1, and 2 wt.%, while the concentration considered for the welding point tests was 0.5 wt.%. The results of the welding point tests showed that the addition of different nanoparticles made it so that welding occurred at much lower pressures compared to the pure oils. This is due to the hardness of the nanoparticles, which increases the local temperature and pressure at the contact points between them and the surfaces, causing welding to occur much sooner. The results of the HFRR tests showed a possible synergistic effect between the fullerenes and SWCNT-COOH and the oil blend, which may be attributed to possible interactions that occurred at a molecular level between the nanoparticles and the different molecules of the oil blend. [ABSTRACT FROM AUTHOR]

Glyceryl monostearate (GMS) was used as an organic friction modifier (OFM) and added to the base oil (PAO10, polyα-olefin) in this study. The film thickness and friction coefficient of the base oil added with GMS (PAO10G) under different slider inclinations and loads were investigated experimentally by using a slider-on-disc contact lubricant film measurement system, and the effect of the adsorption of GMS on the friction behavior of lubricant was studied. Contact angle hysteresis (CAH) was used to evaluate the wettability of the solid–liquid interface, and its correlation with the coefficient of friction was analyzed. The results show that CAH is in good agreement with the wettability of the solid–liquid interface. Compared with the base oil, the wettability of POA10G is weak, which can effectively reduce the coefficient of friction. However, different from the classical lubrication theory, the film thickness of PAO10G is higher than that of PAO10; this unusual phenomenon is preliminarily explained by the interface slippage in this paper. [ABSTRACT FROM AUTHOR]

Attention to greenhouse gases is carried out by reducing CO2 emissions. Emission reduction is achieved using mixed fuels, primarily derived from plant oils. The pertasol-diethyl ether and tamanu oil (PDETO) fuel mixture were tested using a spark ignition engine. The research objective is to obtain fuel specifications and test engine performance using the resulting fuel. Mixed fuels were created from various compositions with codes ranging from BE0 to BE10. Performance testing was conducted using a 110-cc gasoline engine with specific specifications using mixed fuels and compared to commercial gasoline. The research results indicate that engine torque, power, and MeP are higher when using mixed fuels BE0 - BE10 than retail gasoline. The maximum torque that can be achieved is 8.51 NM at 5000 rpm using BE10 mixed fuel, higher than the maximum torque of commercial gasoline, which is 6.81 NM. The highest full power is generated by BE10 fuel, at 7.75 HP at an engine speed of 7000 rpm. The minimum capacity is produced by BE0 fuel, with a power of 6.78 HP at an engine speed of 7000 rpm. Optimal SFC occurs in the BE0 fuel mixture at 7000 rpm engine speed at 0.25 kg/Hp·h. BE10 thermal efficiency reached 31.8%, which is better than commercial gasoline. [ABSTRACT FROM AUTHOR]

Purpose: This paper investigates the predictive impact of Financial Stress on hedging between the oil market and the GCC stock and bond markets from January 1, 2007, to December 31, 2020. The authors also compare the hedging performance of in-sample and out-of-sample analyses. Design/methodology/approach: For the modeling purpose, the authors combine the GARCH-BEKK model with the machine learning approach to predict the transmission of shocks between the financial markets and the oil market. The authors also examine the hedging performance in order to obtain well-diversified portfolios under both Financial Stress cases, using a One-Dimensional Convolutional Neural Network (1D-CNN) model. Findings: According to the results, the in-sample analysis shows that investors can use oil to hedge stock markets under positive Financial Stress. In addition, the authors prove that oil hedging is ineffective in reducing market risks for bond markets. The out-of-sample results demonstrate the ability of hedging effectiveness to minimize portfolio risk during the recent pandemic in both Financial Stress cases. Interestingly, hedgers will have a more efficient hedging performance in the stock and oil market in the case of positive (negative) Financial Stress. The findings seem to be confirmed by the Diebold-Mariano test, suggesting that including the negative (positive) Financial Stress in the hedging strategy displays better out-of-sample performance than the in-sample model. Originality/value: This study improves the understanding of the whole sample and positive (negative) Financial Stress estimates and forecasts of hedge effectiveness for both the out-of-sample and in-sample estimates. A portfolio strategy based on transmission shock prediction provides diversification benefits. [ABSTRACT FROM AUTHOR]

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This study shows the experimental data obtained by Raman spectroscopy to evaluate the structural changes of vegetable lubricants modified with montmorillonite after tribological tests. The analysis of the friction factor and limiting load of wear in the test for the examined grease compound shows a substantial effect on this parameter for grease. A change in the evaluated tribo-parameter results in a modification of the structure of the tested lubricant and changes in the protection efficiency of the tribological system. The amount of thickener, oil base and additive in the grease structure has an influence on the value of anti-wear properties, as shown by the data obtained in the tribological test described in this paper. The Raman spectroscopy tests showed that, in the tribological processes, some of the ingredients undergo an oxidative reaction, which leads to the formation of oxygenated organic substances that form an organic layer on the metal surface and counteract the wear of the lubricated contact surfaces. Other compounds come into close contact with the tribological layer, which increases its ability to resist wear and shear. The efficiency of the used additive is based on the formation (during friction) of a low-shear and high-plastic-strength thin film which is chemically highly bonded to the material and has a high level of durability against wear processes. As a consequence of the thermal decomposition of the additive, chemical interactions occur among the ingredients of the material of the substrate and the lubricants. [ABSTRACT FROM AUTHOR]

Bedding planes are abundant in shale oil reservoirs, but the intrinsic mechanism of fracture-height containment by these weak interfaces remains unclear. To investigate the effects of interface properties, stress conditions, and fracturing fluid viscosity on the vertical propagation of fracture heights in laminated shale oil reservoirs, a three-dimensional hydro-mechanical coupling numerical model was developed. The model is based on the 3D discrete lattice algorithm (DLA), which replaces the balls and contacts in the conventional synthetic rock mass model (SRM) with a lattice consisting of spring-connected nodes, resulting in improved computational efficiency. Additionally, the interaction between hydraulic fractures and bedding planes is automatically computed using a smooth joint model (SJM), without making any assumptions about fracture trajectories or interaction conditions. The results indicate that a higher adhesive strength of the laminated surface promotes hydraulic fracture propagation across the interface. Increasing the friction coefficient of the laminated surface from 0.15 to 0.91 resulted in a twofold increase in the fracture height. Furthermore, as the difference between vertical and horizontal principal stresses increased, the longitudinal extension distance of the fracture height significantly increased, while the activated area of the laminar surface decreased dramatically. Moreover, increasing the viscosity of the fracturing fluid led to a decrease in filtration loss along the laminar surface of the fracture and a rapid increase in net pressure, making the hydraulic fracture more likely to cross the laminar surface directly. Therefore, for heterogeneous shale oil reservoirs, a reverse-sequence fracturing technique has been proposed to enhance the length and height of the fracture. This technique involves using a high-viscosity fracturing fluid to increase the fracture height before the main construction phase, followed by a low-viscosity slickwater fracturing fluid to activate the bedding planes and promote fracture complexity. To validate the numerical modeling results, five sets of laboratory hydraulic fracturing physical simulations were conducted in Jurassic terrestrial shale. The findings revealed that as the vertical stress difference ratio increased from 0.25 to 0.6, the vertical fracture area increased by 1.98 times. Additionally, increasing both the injection displacement and the viscosity of the fracturing fluid aided in fracture height crossing of the laminar facies. These results from numerical simulation and experimental studies offer valuable insights for hydraulic fracturing design in laminated shale oil reservoirs. [ABSTRACT FROM AUTHOR]

The solution to the problem of developing an oxidation-stable dressing with high nutritional value based on unrefined first cold-pressed linseed, corn and sesame oils is considered. The objects of the study are the following indicators: antioxidant, fatty acid composition, induction period of accelerated oxidation of oils, blends and finished products. The rational range of oilratios in the blend, enriched with α-linolenic acid, stabilized against oxidative spoilage due to natural antioxidants – tocopherols, sesamol, sesamolin, is substantiated. The ratio of linseed, corn and sesame oils is 1:2:1, respectively. The characteristics of the blend are as follows: the ratio of ω-3:ω-6 fatty acids is 1:1.7; the induction period of accelerated oxidation (at 80 °C) – 4.1 h. A model sample of the dressing was produced using the developed blend. It was proven that the sample of the dressing of the proposed composition retains its organoleptic and physico-chemical parameters (titratable acidity, dry matter content, acid and peroxide values of the oil fraction) during 30 days of storage at a temperature of 8±1 °C. A feature of the obtained results is the possibility of increasing the nutritional value of the dressing based on unrefined oils while preserving the extended shelf life of products. From a practical point of view, the development of such products allows expanding the range of competitive dressings with high nutritional value. An applied aspect of using the obtained scientific result is the possibility of modeling the composition of dressings or other oil products based on valuable oil raw materials, depending on the ratios of the oil base components of the product. [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]

Wearable medical devices are gaining popularity owing to their potential for seamless integration with the human body and long‐term monitoring of physiological activity. However, conventional adhesives were developed based on the assumption of healthy adult skin and may not account for variations in skin characteristics across different species, environments, and body parts. Consequently, the adhesive strength of wearable devices may significantly differ depending on the skin surface to which they are attached, potentially causing skin damage. In this study, we developed a customized wearable‐device adhesive without skin damage by analyzing the characteristics of the skin surface based on oil and water content and roughness according to different species and parts. Our findings demonstrated that increased root‐mean‐square roughness of the skin surface led to reduced contact area and decreased adhesion force between the polydimethylsiloxane (PDMS) pad and skin surface. Surprisingly, hairless skin exhibited 1.5 times higher adhesion strength than hairy skin due to stronger molecular forces resulting from the higher surface energy of the skin. Additionally, the hole‐patterned PDMS pad on sweaty skin displayed improved adhesion properties compared to the cylinder‐patterned PDMS pad. Therefore, customized wearable adhesives provide an effective strategy for developing skin‐damage‐free wearable devices. [ABSTRACT FROM AUTHOR]

Abnormal wear of the cylinder liner and piston ring in a marine diesel engine will lead to the failure of the diesel engine and colossal energy loss. Using lubricating oil additive with good anti-friction and anti-wear properties effectively inhibits the abnormal wear of cylinder liner and piston rings in diesel engine. The potassium borate/graphene (PB/GN) nano-composite lubricant additive suitable for a marine diesel engine was prepared in this study. Its tribological properties in 500 N base oil were investigated using a pin-on-disk tribotester under various loads and temperature. The frictional surface was comprehensively analyzed using field emission scanning electron microscopy (FESEM), energy dispersive spectrometer (EDS), x-ray photoelectron spectroscope (XPS) and Raman to explore the lubrication mechanisms of the PB/GN nano-composite additive. The results indicated that the PB/GN nano-composite additive could substantially improve the tribological performances of 500N base oil. This could be attributed to the good thermal conductivity of graphene and the tribofilms composed of C, FeO, Fe2O3 and B2O3 formed on the worn surface. The synergy of PB and GN enhanced the tribological performances of base oil. [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 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]

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]

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 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]

This research shows the antifriction and antiwear synergies between a phosphonium ionic liquid (IL) and f-WS2 and f-SiO2 nanoparticles (NPs) as additives of a base oil with low viscosity (PAO6). Mass concentrations of 0.1 wt% nanoadditives and 1% IL were selected to formulate the nanolubricants. Pure sliding and rolling–sliding friction tests were performed at 120 °C, finding great friction reductions in comparison with the PAO6 base oil, specifically for the double hybrid nanolubricant (PAO6 + 1 wt% IL + 0.1 wt% f-WS2 + 0.1 wt% f-SiO2). Regarding the wear produced, the greatest antiwear behavior was also achieved for the double hybrid nanolubricant (width reduction of 48% and worn area decrease of 84%). Furthermore, by means of Raman microscopy and roughness examination of the worn surfaces, it can be proposed that the lubrication mechanism of doubled hybrid nanolubricants could be supported by the adsorbed tribofilm (IL and f-WS2) as well as the mending effects (f-WS2 and f-SiO2). [ABSTRACT FROM AUTHOR]

The present study describes the synthesis and characterization of TiO2 nanoparticles, TiO2 conjugated composites with Multi Walled Carbon Nanotube (MWCNT), Sodium Dodecyl-Sulfate (SDS), and Cetyltrimethylammonium Bromide (CTAB) and its effect on engine oil viscosity. X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR), and (UV-VIS) spectroscopy were used to characterize the synthesized nanomaterials. Prepared nanoparticles were mixed with 50 ml of 15W40 engine lubricant oil. The ultra-sonication instrument was used for even dispersion of the nanoparticles with the engine oil. The intent was to determine the influence of nanoparticles on viscosity characterization of oil at different temperature. The dynamic and kinematic viscosity of various combinations of suspended nanoparticle-lubricant combinations is measured using a redwood viscometer at three temperatures (34 °C, 44 °C, and 54 °C). Test revealed the following important observation: Bare TiO2 nano particles increased the viscosity of base oil, while TiO2 treated with CTAB, SDS and MWCNT decreased the viscosity of base oil up to 27% in cases considered. [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]

New compounds as potential poly(vinyl chloride) plasticizers based on soybean oil and oligoesters of adipic acid and different glycols by one‐pot transesterification are synthesized. In the first step of the plasticizer synthesis oligoesters of adipic acid and diethylene glycol, triethylene glycol, or dipropylene glycol are synthesized, and then in situ in the second step, a defined amount of soybean oil is introduced. By degradation of soybean oil with oligoesters, and transesterification reaction, different compounds are obtained. Their physicochemical properties are determined by NMR, SEC, DSC, TGA, and volatility analyses. The properties of synthesized plasticizers are compared with commercial products: monomeric (DEHP) and aliphatic oligoster of adipic acid and 1,3‐butanediol (H‐1). [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]

[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]

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]

The development of thermo-responsive shape-memory polymers has attracted attention due to their ability to undergo reversible deformations based on temperature changes. Vegetable oils are confirmed to be an excellent biorenewable source of starting materials for the synthesis of polymers. Therefore, the objective of this research was to synthesize thermo-responsive shape-memory polymers based on vegetable oils by using the dual-curing technique and obtaining polymers with tailorable properties. Acrylated epoxidized soybean oil and two epoxidized vegetable oils, linseed oil and camelina oil, were chosen for dual curing with m-xylylenediamine. Rheological tests were used to analyze the curing kinetics of systems undergoing radical photopolymerization, thermal cationic polymerization, and dual-curing processes. The rheological, mechanical, and thermal characteristics of the polymers were enhanced by the second curing stage. Dual-cured vegetable oil-based polymers had shape-memory properties with a recovery ratio of 100%, making them suitable for a variety of applications, including electronics, biomedical devices, and robotics. [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]

Ti3C2Tx/TiO2 composite materials were successfully prepared by hydrothermal reaction method. The phase structure and morphology of the samples were analyzed by X-ray diffractometer and scanning electron microscope. The results show that TiO2 particles are evenly distributed between the layers and on the surface of Ti3C2Tx nanosheets. The prepared composite materials were added to PAO6 base oil, and the MDW-02 friction and wear testing machine was used to study the effects of material addition concentration, working load and working speed on the tribological properties of lubricating oil. The friction test results show that the introduction of Ti3C2Tx/TiO2 composite material can reduce friction, and the maximum reduction of friction and wear was achieved under additive concentration of 1.0 wt%. By scanning electron microscopy analysis of the wear scars, it was confirmed that the prepared nanocomposites repaired the scratched surface and formed a uniform lubricating film, which helped to improve the tribological properties of the base oil. [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]

In order to explore the influence of freeze-drying process parameters on the size of zirconium phosphate (α-ZrP) nanoparticles during freeze-drying, different process parameters were selected and orthogonal experiments were designed to prepare nano α-ZrP with different particle sizes. The structures of nano α-ZrP are characterized by the field emission scanning electron microscope (SEM), and the tribological properties of nano α-ZrP are studied on a tribometer. The orthogonal experimental results indicated that the order of process parameters affecting the size of nano α-ZrP is freezing method > material tray area > reaction temperature. The freezing method has the greatest influence on the size of nano α-ZrP. The particle size is around 20 nm under vacuum freezing, 40 nm under liquid nitrogen freezing, and 60 nm under refrigerator freezing. The reaction temperature of 98 °C, the material disk area of 80 mm2, and vacuum freezing were found to be the optimal process parameters for the preparation of small size nano α-ZrP by freeze-drying. Different amounts of granular nano α-ZrP were added to the base oil; when the addition amount was 2%, the friction coefficient was the smallest, which could be reduced by 34.6%. Friction experiments were conducted on three distinct morphologies of nano α-ZrP (granular, lamellar, and rod); the results show that the friction performance of nano α-ZrP with granular morphology is better than that of the other two crystal morphologies. [ABSTRACT FROM AUTHOR]