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Used lubricating oil is generated by various machinery after extended operation. It is also referred to as spent mobile oil. Extremely hazardous waste lubricating oil is detrimental to the environment because it produces oxidative products when additives break down. Used lubricating oil is classified as a hazardous waste substance and has a negative impact on the environment. Polychlorinated biphenyls (PCBs), carcinogenic substances and other impurities make lubricating oil poisonous and pose a serious threat to human health and the environment. Re‐refining is considered the preferred technology for resource conservation, waste minimisation and reduced environmental hazards. The present study focuses on optimising the method of re‐refining waste lubricating oil. The effects of various operating parameters such as refining time, refining temperature, solvent‐to‐used oil ratio and flocculant dosage have been extensively studied to maximise the percentage recovery of lubricating oil. Optimum process parameters are (i) a refining time of 80 min, (ii) a refining temperature of 48°C, (iii) solvent‐to‐waste oil ratio of 5:1 (w/w) and (iv) a flocculant dosage of 2 g/kg of solvent; the optimum yield was found to be 75% with the solvent extraction method and 78% with the extraction–flocculation method, respectively. The purity and physico‐chemical properties of the recovered oil were thoroughly analysed using Fourier transform infrared spectroscopy and ASTM standard methods. It was concluded that refined oil can effectively reduce the ongoing oil crisis and create a clean, healthy environment. [ABSTRACT FROM AUTHOR]

As an emerging two‐dimensional material, black phosphorus (BP) has excellent tribological properties, but the poor dispersion of BP in oil inhibits its application in friction to some extent. Surface modification is one of the effective methods to solve the dispersibility of BP, and the use of nano‐Fe3O4 dotted on the surface of BP improves the dispersion stability of BP in soybean from 3 days to about 15 days. Compared with pure soybean oil, friction coefficient and wear rate of the addition of 0.12 wt% BP/Fe3O4 are reduced 65% and 78%, respectively. To elucidate the excellent tribological mechanisms of BP/Fe3O4 as additives in soybean oil, the compositional and structural characterisation of the abrasion mark surface was studied accordingly. On the one hand, soybean oil reacts with BP/Fe3O4 to form a composite tribo‐film during the scraping process. This tribo‐film composed of amorphous carbon, iron oxide and phosphorus oxide nitrides prevents direct contact between the sliding interfaces. On the other hand, BP and Fe3O4 nanoparticles form a mechanical rollerball structure, which can further reduce interfacial friction and wear through synergistic lubrication. The results provide new insights into the design of additives in biomass lubricating oils and propose new application prospects for BP in the field of lubricating additives. [ABSTRACT FROM AUTHOR]

Waste plastics bring about increasingly serious environmental challenges, which can be partly addressed by their interconversion into valuable compounds. It is hypothesized that the porosity and acidity of a zeolite‐based catalyst will affect the selectivity and effectiveness, enabling a controllable and selective conversion of polyethylene (PE) into gas‐diesel or lubricating base oil. A series of embryonic, partial‐ and well‐crystalline zeolites beta with adjustable porosity and acidity are prepared from mesoporous SBA‐15. The catalysts and catalytic systems are studied with nuclear magnetic resonance (NMR), X‐ray diffraction (XRD), and adsorption kinetics and catalytic reactions. The adjustable porosity and acidity of zeolite‐beta‐based catalysts achieve a controllable selectivity toward gas‐diesel or lubricating base oil for PE cracking. With a catalyst with mesopores and appropriate acid sites, a fast escape and reduced production of cracking of intermediates are observed, leading to a significant fraction (88.7%) of lubricating base oil. With more micropores, a high acid density, and strong acid strength, PE is multiply cracked into low carbon number hydrocarbons. The strong acid center of the zeolite is confirmed to facilitate significantly the activation of hydrogen (H2), and, an in situ ammonia poisoning strategy can significantly inhibit hydrogen transfer and effectively regulate the product distribution. [ABSTRACT FROM AUTHOR]

Aviation lubricating oil, as the "blood of machine operation", plays an important role in the lubrication, cooling, cleaning, sealing, rust prevention, and other aspects of aero‐engines, thereby ensuring the safe and stable long‐term endurance of aero‐engines under high‐speed and high‐temperature conditions. The thermal oxidation of aviation lubricating oil leading to decay is the most important factor causing lubricating oil failure, which will seriously affect the performance of aero‐engines and endanger flight safety. Here, we comprehensively summarize the oxidation mechanism of aviation lubricating oil, factors affecting thermal oxidation of aviation lubricating oil, evaluation methods for thermal oxidation of aviation lubricating oil, and antioxidants that inhibit thermal oxidation of aviation lubricating oil. We hope that this review can enhance readers' understanding of the thermal oxidation of aviation lubricating oil, stimulate broader interest, and promote more exciting development in this promising field. [ABSTRACT FROM AUTHOR]

Switchable solvents (SS) are a class of liquids with the unique ability to significantly alter their physical properties in response to external stimuli such as changes in temperature or the introduction or removal of CO2 gas. This reversible behaviour allows them to return to their original state with minimal changes, making them highly advantageous for various applications. A notable example of a switchable solvent is waste carbon dioxide gas, which is non‐toxic, non‐flammable, and cost‐effective. The versatility of switchable solvents extends to their polarity and physical states, which can be modified through molecular adjustments, opening new pathways for research and industrial applications. This review provides a comprehensive overview of switchable solvents, including their classification, history, properties, and applications, with a particular focus on their role in green chemistry. The types of switchable solvents discussed include Switchable‐Polarity Solvents (SPS), Switchable‐Hydrophilicity Solvents (SHS), and Switchable Water. Each type is examined in terms of synthesis, chemical properties, and development. The desirable properties of switchable solvents, such as their efficiency and recyclability, make them suitable alternatives to traditional solvents in various fields. Their applications range from water treatment and oil extraction to cleaning solid particles and recovering residual motor oil. Additionally, switchable solvents have proven effective as reaction media and in recovering polystyrene from foam. This paper also highlights the environmental benefits of switchable solvents, emphasizing their role in reducing the ecological impact of chemical processes. The potential for future developments in this field is significant, with ongoing research aimed at enhancing their performance and expanding their applications. By providing a detailed analysis of switchable solvents, this review aims to support researchers and industry professionals in developing more sustainable and efficient chemical processes. [ABSTRACT FROM AUTHOR]

ABSTRACT Here, we demonstrate mid‐field 1H NMR spectroscopy combined with chemometrics to be powerful in the classification and authentication of motor oils (MOs). The 1H NMR data were processed with a new algorithm for simultaneous phase and baseline correction, which, for crowded spectra such as those of the refinery products, allowed for more accurate estimation of phase parameters than other literature approaches tested. A principal component analysis (PCA) model based on the unbinned CH3 fingerprint region (0.6–1.0 ppm) enabled the differentiation of hydrocracked and poly‐α‐olefin‐based MOs and was effective in resolving mixtures of these base stocks with conventional base oils. PCA analysis of the 1.0‐ to 1.14‐ppm region enabled the detection of poly (isobutylene) additive and was useful for differentiating between single‐grade and multigrade MOs. Non‐equidistantly binned 1H NMR data were used to detect the addition of esters and to establish discriminant models for classifying MOs by viscosity grade and by major categories of synthetic, semisynthetic, and mineral oils. The performances of four classifiers (linear discriminant analysis [LDA], quadratic discriminant analysis [QDA], naïve Bayes classifier [NBC], and support vector machine [SVM]) with and without PCA dimensionality reduction were compared. In both tasks, SVM showed the best efficiency, with average error rates of ~2.3% and 8.15% for predicting major MO categories and viscosity grades, respectively. The potential to merge spectra collected from different NMR instruments is discussed for models based on spectral binning. It is also shown that small errors in phase parameters are not detrimental to binning‐based PCA models. [ABSTRACT FROM AUTHOR]

ABSTRACT The anti‐emulsification property of lubricating oil is an important index to measure the quality of oil. In this paper, the behaviour of surfactants such as lubricating oil additives at the oil–water interface and the influence of the position of ethylene oxide (EO) and propylene oxide (PO) in the block polyether demulsifier on the demulsification effect were investigated by molecular simulation and experimental verification. The properties of seven lubricating oil additives with different functions and two pairs of isomers were investigated by molecular simulation, and their demulsification effects were verified by experiments. Some simulation results such as interface thickness and density distribution can accurately predict the experimental demulsification effect. Moreover, it was found that the position isomerism of surfactants affected the demulsification performance by changing the lipophilic balance and interface properties. The demulsification performance of sequenced copolymers is generally better than that of anti‐sequenced copolymers. The accurate prediction of molecular dynamics simulation makes the selection of lubricating oil demulsifier more extensive and has practical application value. [ABSTRACT FROM AUTHOR]

This work describes the production of a novel biosurfactant produced by the bacterium Bacillus invictae UCP1617 cultivated using an alternative substrate and its use in the formulation of an eco‐friendly detergent. A factorial design was used to optimize agitation, temperature, and inoculum size in a mineral medium containing 1.5% corn steep liquor in 100‐mL shake flasks. The best conditions (175 rpm, 28°C, and 4% inoculum) were used to scale up biosurfactant production in a 50‐L bioreactor. Surface tension of the fermentation medium decreased from 69.5 to 30.2 mN/m within 72 h. The biosurfactant exhibited a critical micelle concentration (CMC) of 0.900 ± 0.08 g/L. The biosurfactant formed stable oil‐in‐water emulsions of motor oil and petroleum, achieving emulsification indices of 90.80% and 99.00%, respectively. An eco‐friendly detergent was formed that included biosurfactant at several different concentrations, 0.2 (wt) % hydroxyethyl cellulose and 0.2% potassium sorbate. The detergent remained stable under extreme conditions of pH, temperature, and salinity when stored for 90 days. The detergent was nontoxic to cabbage, cherry tomato plants, and the microcrustacean Artemia salina. A detergent formulation containing biosurfactant at the CMC completely dispersed motor oil in seawater at a 1:1 surfactant/oil (vol/vol) ratio and removed 99.21% of motor oil (20 mL) contained in 60 g of clayey soil. The detergent removed 98.42% of the oil adhered to a glass surface and removed 75.00% of motor oil adsorbed to a porous surface. The application of this biosurfactant as an environmentally friendly additive for remediation processes is feasible. [ABSTRACT FROM AUTHOR]

Reusing industrial waste is one of the new tactics being used to fight the dumping of solid waste for environmental protection. In the current work, the waste polyurethane (WPU) was ground to a fine powder and used for reinforcement of devulcanized waste rubber/styrene butadiene rubber (DWR/SBR) blends. DWR/SBR/WPU composites were prepared using (0, 3, 6, 9, 15, 30) phr (parts per hundred of rubber) of WPU. It was hypothesized that the treatment of WPU with trimethylolpropane triacrylate (TMPTMA) and irradiated at 10 kGy would improve its compatibility with the DWR/SBR blend and, consequently, its reinforcement efficacy. The incorporation of 30 phr of treated WPU (TWPU) improved the tensile strength (TS) by 47.7% and 8.6% compared to neat DWR/SBR and composites containing 30 phr of untreated WPU (UWPU). In addition, the incorporation of TWPU improved other mechanical characteristics such as tear strength, hardness, and abrasion resistance. As a result of increasing polarity and cross‐link density within the DWR/SBR blend after the addition of polar WPU, the resistance to motor oil was improved. The outcomes are encouraging from the standpoint of the circular economy and help produce high‐performing, reasonably priced DWR/SBR composites for a range of industrial uses, especially in the floor tiles application. Highlights: Waste polyurethane (WPU) was activated using gamma irradiation in the presence of TMPTMA.The treatment of WPU improved its compatibility with DWR/SBR blend.The impact of WPU treatment on the properties of DWR/SBR blend was investigated.TWPU improved the mechanical properties of DWR/SBR blend more than UWPU.TWPU increased the motor oil resistance of DWR/SBR blend more than UWPU. [ABSTRACT FROM AUTHOR]

The current study encompasses a comprehensive assessment of three biopolymeric flocculants on the overall performance of recycling waste lubricating oil to achieve a higher percentage recovery, flocculation efficacy, and better quality of recovered base oil. The findings reveal that with experimental conditions such as (i) mixing time of 80 min; (ii) agitation speed of 400 rpm; (iii) reaction temperature 50°C; (iv) solvent to waste oil ratio 3:1 g/g; and (v) flocculant dosage 1 g/ kg of solvents, 1‐butanol and sodium alginate gives highest percentage yield of 91% followed by corn starch of 89.10% and xanthan gum of 87.18% as bio‐polymer flocculant. The effects of various process parameters of bio‐flocculants on flocculation efficiency are expounded. With the process parameters of (i) initial pH of 5.9, 6.0, and 6.2; (ii) mixing time − 59, 60, and 63 min; and (iii) solution temperature of 59, 60, and 62.2°C, maximum flocculation efficacy (% sludge removal) of 16.24%, 13.01%, and 14.09% were attained for the cases of refined oil treated with sodium alginate, corn starch, and xanthan gum, respectively. Results also reveal that the physicochemical properties of refined base oil treated with 1‐butanol and sodium alginate as bio flocculant are almost close to the virgin lubricating oil. The optimum recovery of high‐quality base oil with the adoption of green technology and solvent–bio flocculant combination can mitigate the environmental impact of waste oil and create an energy‐efficient sustainable condition for the regeneration of re‐refined base oil. [ABSTRACT FROM AUTHOR]

Utilizing nanorefrigerants as working fluids can significantly enhance the energy efficiency of low‐temperature waste heat recovery systems (≤ 50°C). Refrigerants with low viscosity and density require a substantial amount of surfactant to maintain a stable suspension of nanoparticles. However, the excessive use of surfactants, which have a notably low thermal conductivity, could lead to foam generation and reduce heat transfer coefficient. High viscosity lubricating oils with small amount of surfactant can prolong the stable suspension time and produce repulsive force. Therefore, a new combination of them improves the stability of TiO2/R141b nanorefrigerants. Additionally, viscosity and thermal conductivity of the nanorefrigerants were optimized using an implementation of a modified non‐dominated sorting genetic algorithm (NSGA‐II). The results show that adding lubricating oil inhibits aggregation of the nanoparticles leading to a stable suspension for more than 6 h at volumetric mixing ratios (lubricating oil: refrigerant) greater than 1:30. The best dispersion stability was achieved at surfactant polyvinyl pyrrolidone (PVP) mass ratio of 0.5, and the average absorbance value was increased by 65.45%. Compared with pure refrigerants, the thermal conductivity of TiO2/R141b (0.15 vol.%) nanorefrigerant was enhanced by up to 12.59% under the optimum mixing ratio. Moreover, the studied nanorefrigerants exhibited shear thickening behavior throughout the studied shear rate range, with increased non‐Newtonianization with decreasing temperature. Finally, the Pareto points were divided into three representative groups based on thermal conductivity and viscosity. These findings suggest enhanced high heat transfer efficiency with pumping power of nanorefrigerant in the waste heat recovery systems. [ABSTRACT FROM AUTHOR]

NMR methods were applied for lubricant analysis. Different factors influence the real aging of lubricants on diverse length scales and are captured by NMR. Chemical conversion of additives is addressed by NMR spectroscopy. High‐field NMR experiments allow the identification and quantification of chemical components and are transferred to benchtop devices. Molecular dynamics and contaminations like fuel or abrasion are addressed via NMR relaxation and diffusion. Quality parameters were extracted via suitable data analysis of NMR raw data, which allow the detection of aging and indicate changes in the oil composition. At the same time, the methodology is optimized to the conditions in quality control. The feasibility is shown the example of a series of lubricants from applications in regenerative energy production, namely, wind turbine oils and biogas motor oils. [ABSTRACT FROM AUTHOR]

In this research, an angular contact ball bearing with two‐half inner rings is used as a carrier. Considering the two‐phase flow characteristics of oil and air in the bearing, the flow characteristics of lubricating oil inside the bearing with under‐race lubrication are studied. Based on the volume of fluid (VOF) method and the standard k–ε turbulent flow model, the characteristics of oil and air two‐phase flow inside the ball bearing are analysed. The bearing internal pressure field distribution, streamline distribution, and other flow properties for the different radial working clearances, pocket clearances and guide clearances are determined. The distribution of the lubricating oil in key areas is observed. The oil phase volume fraction of the key lubrication areas, such as the cage pocket surface and the inner and outer ring surfaces is used to evaluate the influence of different structural parameters on the bearing lubrication performance. The lubrication influences of the inner and outer guides of the cage are evaluated, and the internal flow characteristics of the bearing are analysed with different guide clearances. The results show that with the radial working clearance range from 0.100 to 0.145 mm, the pressure in the working contact area of the bearing decreases 26%. The pocket clearance ranges from 0.48 to 0.28 mm, and the pressure in the working contact area of the bearing significant increases from 0.642 to 1.165 MPa. From this perspective, the larger the radial working clearance and pocket clearance are, the more favourable it is for bearing lubrication. For bearings with under‐ring lubrication, when the bearing adopts outer guidance, the distribution of lubricating oil in the key areas of the bearing is worse than that for internal guidance. However, the pressure in the working contact area of the bearing slightly increases from 0.642 to 0.759 MPa with the inner guide clearance increasing from 0.4 to 0.8 mm. [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]

Decellularized extracellular matrix (dECM) retains the bioactive components to mimic tissue‐specific microenvironment. Designing dECM‐based inks for 3D printing to prepare scaffolds can enhance the regeneration of corresponding tissues. However, due to the strict requirements for inks, how to efficiently prepare dECM‐based inks is a challenge. Inspired by granular lubrication, the present study proposes an effective and general method for preparing granular ink from dECM microparticles (MP) with high content. Through dopamine polymerization, dECM‐MPs are coated with polydopamine (PDA). Meanwhile, gelatin methacryloyl (GelMA)‐based microspheres (GelMA‐MSs) are prepared with available double bonds. dECM‐MPs (30–40 wt%) and GelMA‐MSs assemble to form a granular ink, exhibiting well‐performed extrudability, plasticity, and fidelity. Further inspired by joint lubrication, hyaluronic acid (HA) is introduced into PDA coating and GelMA‐MSs to reduce the micro‐interface friction, further promoting the printability and broadening the printable window of dECM‐MPs content to 30–60 wt%. Osteochondral scaffold and skin wound dressing are fabricated through 3D printing from the corresponding dECM‐MPs, enhancing the regeneration of the corresponding tissues in vivo. Especially, the realization of printability of highly rigid dECM‐MPs confirms the universality, reliability and efficiency of the present strategy. [ABSTRACT FROM AUTHOR]

Waste motor oil (WMO), which has no stable form or structure, causes major environmental problems and damage to the ecosystem once it is disposed to the environment. Because of the high toxicity of contents in such effluent, it must be treated before being discharged into the receiving environment. In recent years, the valorization and the use of waste materials to remove toxic pollutants is of great importance to researchers and diverse industries. In this study, the usability of waste welding powder (WWP) as an adsorbent for waste oil removal was investigated. For this purpose, investigating the usability of material, which is generated as industrial waste, in wastewater treatment will lead to the evaluation of waste. The effects of temperature, pH, WWP amount, and initial WMO amount were investigated. According to the adsorption studies, 1 g WWP/L of the processed adsorbent was able to effectively remove 95.05% of WMO (100 mg) at a pH of 2 at 30°C. Stereo microscopy images showed a large amount of oil adsorbed on the WWP surface. The different WWP properties were determined by adsorption isotherm (Harkins–Jura), kinetic (pseudo‐second order), and thermodynamic (ΔG: −5.1 kJ mol–1) experiments. It is thought that WWP, which is a low‐cost and waste material, can be used as a promising adsorbent in WMO removal. [ABSTRACT FROM AUTHOR]

Oil‐containing nanocapsules are prepared and used to solve the challenges arising from the low mechanical properties and high coefficient of friction (CoF) of epoxy resin (EP). The shell of the nanocapsules is amorphous carbon and the core is lubricating oil (ATF6, Automatic Transmission Fluid 6). The nanocapsules are uniform hollow spheres with an average particle diameter of 530 nm and a shell thickness of 60 nm. The mass content of the lubricating oil encapsulated in the nanocapsules can reach 64.88% upon vacuum impregnation. Enhancing with the oil‐containing nanocapsules, the tribological properties of EP composites are studied in detail. Compared with those of neat EP, the compressive strength of the EP composite with 7 vol% nanocapsules improves by 9.2%, and the CoF and wear rate reduce by 71.70% and 89.38%, respectively. During the friction process, the oil‐containing nanocapsules are crushed and the oil is released, which contributes to the antifriction property of EP composites. Moreover, the results are expected to open up new ideas for the research and development of self‐lubricating materials. [ABSTRACT FROM AUTHOR]

In this work, the influence of polytetrafluoroethylene (PTFE) filler size and testing conditions (i.e., air, water, and lubricating oil) on the tribological properties of poly(arylene ether nitrile) (PEN) was systematically investigated. The results showed that the addition of PTFE was beneficial to improve the tribological properties of PEN‐based composites which was related to the easier formation of transfer film on the surface of friction pair. Samples which were tested in water demonstrated a relatively higher friction coefficient (μ) and wear loss when compared with those tested in dry air and lubricating oil scenarios, which was attributed to the fact that friction induced heat and wear debris could be timely removed by water. In addition, the infiltration of water further reduced the interaction between PTFE filler and PEN, which aggravated the wear loss of sample blocks. When tested in lubricating oil, pure PEN showed the lowest wear loss when compared with that of PEN/PTFE composites. At a given content (20 wt%) of PTFE fillers, PEN/PTFE1.5μm exhibited the lowest μ in lubricating oil whereas PEN/PTFE5μm demonstrated the lowest specific wear loss in air condition (1.18 × 10−6 mm3/N·m). This work provided some useful information for the design and application of PTFE‐containing polymer composites that can be targeted in different lubrication scenarios in industrial fields. [ABSTRACT FROM AUTHOR]

Lubricants are of paramount importance in protecting metallic contact surfaces and reducing friction. The viscosity of lubricating oil can be engineered by introducing long linear polymers, such as poly(lauryl methacrylate) (PLMA). In particular, the formation of adsorption films by using polymers with hydroxy or amino side groups has attracted much attention in recent years. In this study, copolymers with controlled structure were synthesised by SARA ATRP, which can be used in large scale production. A comparison of friction and wear under boundary lubrication was conducted using both statistical and block copolymers with low Ð. Friction test results using a reciprocating sliding machine (SRV) showed that the block copolymers were less likely to desorb from the metal surface than the statistical copolymers. In addition, the wear evaluation after the SRV test showed that the block copolymer had less wear and less wear debris. [ABSTRACT FROM AUTHOR]

Waste lubricating oil is non‐biodegradable materials. It is released into the environment and its disposal has become a global environmental issue due to its impact on all life aspects. The production of waste lubricating oil has recently increased rapidly. The aim of this work is to recover, optimize oil production process from waste lubricating oil. This was investigated using the acid‐clay process. Response Surface Methodology (RSM) approach was used to optimize the desludging reaction. The studied parameters were acid to oil ratio, contact time, temperature. The mixing ratio of acid to waste oil were selected in the range of 1:10 to 2:10 (v/v). Reaction time was in the range of 60–120 min. The predicted maximum viscosity index of 117.54 was obtained at the temperature of 40°C, 20% acid to oil ratio, and reaction time of 60 min. The results were assessed experimentally using five runs and the average value of viscosity index was 111.76 with standard deviation of 0.739 and error 4.91%. The samples obtained at optimum conditions were characterized by measuring flash point at 180°C, carbon residue of 0.487, kinematic viscosity at 100°C of 17cSt, the water content of 0.01%, ash content of 0.02%. Viscosity index of was found in complies with the Egyptian standards. [ABSTRACT FROM AUTHOR]

The causes of corrosion failure of 20CrMnTi rusted gear were analyzed by quantitative analysis of the composition, observation of the microstructure, hardness test and electrochemical test. The microstructure characterization showed that the proportion of retained austenite in the rusted gear was slightly higher and the length‐width ratio of martensite on the surface of addendum of rusted gear was slightly larger than that of the normal gear. However, the corrosion resistance of the rusted gear surface was similar to that of the normal gear. The lubricating oil of the gear was detected to contain water molecules. Further investigation showed that continuous rainy days during the period from installation to disassembly led to a relatively high humidity environment and also the block cover was not installed at that time. Therefore, the corrosive medium continuously entered the gearbox through the block cover hole and destroyed the protection of lubricating oil film, resulting in serious erosion of the gear near the block cover hole. After securing the problem, the block cover was kept installed all the time and no such corrosion failure occurred again. [ABSTRACT FROM AUTHOR]

Hydroxy fatty acids (HFAs) have long been a staple component of feedstock oils with uses ranging from motor oils to food to pharmaceuticals. Castor oil, which contains the HFA ricinoleic acid as its principal component, is the most widely used source of HFA in the world. In addition, bisphosphonates are a functional moiety that has been shown to display a variety of industrial applications, ranging from use in water softeners to osteoporosis drugs, primarily due to their affinity for the calcium ion. We have long been interested in the modification of ricinoleic acid from castor oil to phosphorus derivatives, including α‐hydroxy phosphonates and phosphonic acids, and have now accomplished the synthesis of a family of ricinoleic‐derived bisphosphonates: one that retains the cis alkene found in ricinoleic acid and one where the alkene has undergone hydrogenation. These compounds have been produced in high yields and high purity and the synthesis of these compounds is reported. [ABSTRACT FROM AUTHOR]

In the study, the waste polyvinylidene fluoride (PVDF) membranes were recovered and the obtained resin powders by a solvent recovery method were employed for the fabrication of a novel PVDF‐based tribological composite. Herein, a new strategy was developed for applying the waste PVDF membranes to fabricate a self‐lubricant composite, where the recycled PVDF powders acted as the polymer matrix and microcapsules with the configuration of polysulfone (PSF) capsuling lubricant oil (PAO) served as the filler. The morphologies, crystal phases, chemical components and groups as well as thermal stabilities of fabricated PAO@PSF/PVDF composites were characterized, and the self‐lubricating and wear properties of fabricated composites were tested under the dry sliding condition using a ball‐on‐disc configuration. Experimental results suggest that the PAO@PSF/PVDF composite with an addition of 20 wt% PAO@PSF microcapsules exhibits the best tribological properties, in view of the lowest friction coefficient (0.077) and the smallest wear rate (2.34 × 10−15 m3/Nm). The incorporation of PAO@PSF microcapsules greatly reduces the friction coefficient of PVDF polymer. The tribological properties of fabricated PAO@PSF/PVDF composite will be expectable to that of the PVDF polymer with the dripping presence of lubricating oil. [ABSTRACT FROM AUTHOR]

The aging behavior and degradation mechanism of fluoroelastomers (FKM) after exposure to thermal air, commercial lubricating oil, and the corresponding base oil at elevated temperatures were investigated. The FKMs immersed in oil and exposed to air are denoted by FKM‐O and FKM‐A, respectively. The crosslinking densities of the samples were determined by equilibrium swelling and dynamic mechanical analyses, and the results were different. Compared to the performances of FKM‐A, noticeable changes in the mechanical and swelling performances of FKM‐O were observed, attributed to the severe deterioration induced by both the lubricating oil and the high‐temperature. The FTIR results revealed that the dehydrofluorination induced by the oil caused the fracture of the CF bonds, and the degradation of the oil itself exerted negative impacts on the properties of the FKM. The findings of this study will facilitate the development of FKMs with degradation‐resistant properties for various applications. [ABSTRACT FROM AUTHOR]

Lubricating greases are an important class of lubricants to reduce wear and friction in moving components. SP [ sp [[1]] SP ] sp Greases consist of a thickener network which includes base oil and additives of typically low molecular weight. As expected, signals from base oil molecules, thickeners and the alkyl chains of additives were clearly detected in the SP 1 sp H-NMR spectra at 80 MHz. This reveals that additives have a strong influence on the interaction of base oil and thickener and might also affect the thickener and its structure. [Extracted from the article]

Machine learning tools for analysing lubricating oil data have enabled better information in the condition based maintenance (CBM) approach to the process of diagnosing and predicting failures in diesel‐powered vehicle fleets. With the increase in the number of sensors inserted in vehicles, it is possible for companies to stockpile large quantities of information in real time. As such, the development of data‐driven tools will enable accurate identification of the level of wear of a system, evolving CBM into a more reliable and dynamic approach. Following this type of data‐based analysis focusing on determining the wear of systems and equipment, this paper presents an intelligent system for assessing the condition of lubricating oil in automotive diesel engines. To this end, we analyse the use of raw data obtained from the sensors installed in the car and evaluate in conjunction with the insertion of engineered features designed the best way to determine the operating state of the oils. The results presented in this analysis show that to explain 90% of the variation in the original data only the variables kinematic viscosity, dynamic viscosity, engine oil temperature and OSF_v3 are needed. After evaluating the quality of the variables, we conducted an experimental study to analyse the performance of various machine learning algorithms, taking into account the number of features as input data. The results show that the proposed system has the ability to identify the operating conditions of lubricating oil using seven variables as input to a model based on gradient boosting, obtaining a recall result of 93%, precision of 96% and F1‐score of 94%. We conducted a set of additional studies to understand how different subsets of variables affected the performance of the models, and the results show that the best combination includes information regarding the engine speed, coolant and oil temperature, oil pressure, the oil stress factor (OSF_v3), kinematic viscosity, and the dynamic viscosity. [ABSTRACT FROM AUTHOR]

Nanoadditive with multifunctional properties holds commercial importance in the lubricant industry. Herein, GO‐N‐PPDA was synthesised as nanoadditive by functionalizing graphene oxide (GO) using N‐phenyl‐p‐phenylenediamine and characterised by Fourier transform infrared spectroscopy, X‐ray diffraction analysis, thermogravimetric analysis, scanning electron microscopy and transmission electron microscopy analysis. The antioxidant behaviour of GO‐N‐PPDA was analysed by 2,2‐diphenyl‐1‐picryl‐hydrazyl‐hydrate. The nanoparticles dispersed mineral base oil (N‐250) in 0.2%, 0.4%, 0.6% (w/v) concentrations were evaluated for tribological, rheological and thermophysical analysis by ASTM methods. The flow behaviour of the nanolubricant shows shear thickening behaviour with an increase in shear rate. In contrast, tribological results indicate a significant reduction in wear scar diameter and coefficient of friction to the base oil. Furthermore, GO‐N‐PPDA shows improved thermophysical properties compared with the mineral base oil. Thus, GO‐N‐PPDA shows multifunctional behaviour in terms of viscosity index, pour point, antioxidant activity, rheology and tribological properties. [ABSTRACT FROM AUTHOR]

Polyalphaolefins (PAOs) have potential applications as synthetic lubricants in automotive, industrial, and aviation equipment, including motor oils, hydraulic, and transmission fluids. During the present work, the linear higher alpha olefins (LHAOs) ranging from C8 to C12 present in the refinery stream (RS) are polymerized using Lewis acid catalyst combination of transition metal halide of Group 4, that is, TiCl4 and Group 13 metal halide, that is, AlCl3. The influence of Ti:Al (1:1, 1.5:1, 1:2, and 2:1) molar ratios, polymerization time (2–8 h), and polymerization temperature (100–170°C) on the polymerization behavior of LHAOs were also investigated. The synthesized PAOs were characterized using different analytical techniques, including 1H‐13C nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FT‐IR), thermogravimetric analysis (TGA), and gel permeation chromatography (GPC). The performance evaluation of PAOs was evaluated in terms of density, pour point, oxidation stability, thermal stability, kinematic viscosity (KV), viscosity index (VI), friction, and corrosion studies. The synthesized PAOs exhibit low pour point (<−30°C) and high VI (120–150), making them suitable synthetic lubricant for various applications. [ABSTRACT FROM AUTHOR]

A supply and demand balance control method for an electrical submersible linear motor utilised in offshore oil exploitation is proposed in this study. The permanent magnet linear motor is replaced by an electrical submersible linear motor based on switched reluctance linear motor. The sensorless control method further enhances the stability of the oil exploitation system. Meanwhile, a supply and demand balance control method is proposed to maintain the fullness of the submersible plunger pump within an ideal range. An established speed function allows the speed of the electrical submersible linear motor to dynamically alter in response to the change in oil deliverability and increasing the system's production. Additionally, maintaining the fullness of the submersible plunger pump within the ideal range helps simplify the model and increase computation accuracy. Finally, the supply and demand balance control method is validated and compared with the intermittent oil exploitation control method by simulations and experiments. Results from the simulations and experiments indicate that the proposed method can increase the production of the offshore oil exploitation system in addition to causing the motor to follow changes in oil deliverability and adjust the speed. [ABSTRACT FROM AUTHOR]

Slippery liquid infused porous surface (SLIPS) inspired by the microstructure of carnivorous Nepenthes has the potential to be used in a wide range of fields, including nautical, industrial, medical, etc. Due to their excellent optical transparency, self‐healing after mechanical injury and controllable wetting properties, SLIPS has attracted extensive research interest. With appropriate lubricants, sufficient performance will be armed to the surface so as to adapt for further requirements. In this review, the first part focuses on the basic theory of the different wettable models explaining the physical phenomena of these surfaces and their wettability. Then various representative fabrication methods are listed such as lithography, layer‐by‐layer assembly, and electrochemical anodic oxidation. There are three steps including in the process of SLIPS preparation:fabrication of rough substrate, chemical modification of rough substrate and infusion of low surface energy lubricating oil. Furthermore, recent applications and researches of SLIPS are introduced, mainly about drag reduction, anticorrosion, anti‐icing, medical treatment, and droplet manipulation. Finally, make a prospection to the limitations of practical application and future development direction of the technology. [ABSTRACT FROM AUTHOR]

Fluoroelastomer (FKM) has been widely used in aerospace and some particular fields, whose aging is a key problem to influence the service life of the systems. The aging behaviors of FKM in the lubricating oil have been investigated in our previous study. In this work, the influence of intentionally aged or oxidized lubricating oil (A‐O) on the aging process of FKM is reported for the first time comparing with the situation in the fresh oil (F‐O). As the oil medium aged at 200°C for different time, its color, acid number and contact angle with FKM change evidently indicating possible oxidation might occur although the Fourier transform infrared spectrometer (FTIR) has little change. Then, the influence of aged oil medium on the aging behaviors of FKM was further examined. Compared with F‐O, the aging process of FKM in A‐O was significantly accelerated as evidenced by FTIR, tensile strength, mass change, DMA, and macroscopic observation. With the increase of aging temperature from 150 to 200°C, the contrast between A‐O and F‐O conditions become more prominent. Specifically, at 200°C, the crosslinking density and tensile strength of FKM in A‐O decreased by 2.2 × 10−4 mol/cm3 and 2.5 MPa compared to that in F‐O, and the mass change reached to 3.8%, which might be due to the higher amount of oil medium by diffusion into the FKM matrix. [ABSTRACT FROM AUTHOR]

Slippery liquid‐infused porous surface (SLIPS) is an emerging anti‐icing method. The anti‐icing mechanism of SLIPS is to prevent the heat transfer from liquid droplets to the surface by forming an oil film on the solid surface. However, the contact area between the droplet and the surface of the specimen increases due to the existence of the oil film, which accelerates the heat transfer and emergence of ice. Herein, in order to further improve the anti‐icing performance of SLIPS, a microscale square column array is fabricated by wire cut electrical discharge machining (WEDM) technology, on which a circular hole structure is constructed by nanosecond laser. Lubricating oil is then injected into the fluorinated surface to produce SLIPS. The maximum contact angle (CA) of the surface is 150° ± 1.2° and the contact angle hysteresis (CHA) is 1.2°. The contact mode of droplets on the surface is liquid–oil and liquid–gas, which is a multiphase mixing interface. The icing test shows that the icing time of the droplet is 4785 s at a surface temperature of −10 °C, exhibiting a good icing‐delay performance. [ABSTRACT FROM AUTHOR]

Methyl methacrylate (MMA) functionalized polyethylene additives for improving the properties of lubricating oil has been investigated in which poly(MMA‐co‐ethylene) were synthesized by using three different polymerization techniques such as miniemulsion, post polymerization and reverse atom transfer radical polymerization with 1.0 molL −1 of MMA and 20 bar of ethylene pressure. The copolymers are block in nature with the composition of 1:3 molar ratios of ethylene:MMA which is independent of polymerization techniques used. 1H NMR analysis confirmed the successful incorporation of the copolymers in the lubricating oil. Thermogravimetric analysis reveals that the addition of poly(MMA‐co‐ethylene) increases thermal stability of the additive doped lubricating oil by approximately 40°C with a single stage decomposition pattern. Flash point measurements show an increasing flash point values for copolymer doped lubricating oil. From rheological study, the viscosity index of base lubricating oil has found significant increases from 102 to 129 with the addition of poly(MMA‐co‐ethylene) and the higher molecular weight (MW) of this copolymer provides better thickening efficiency. However, copolymer with higher MW seems to be more susceptible to mechanical degradation resulting in lower shear stability whereas copolymer with lower MW acts as a better pour point depressant. [ABSTRACT FROM AUTHOR]

This article studies the lubrication state of the arc tooth cylindrical gears during injection lubrication. The mathematical model of arc tooth cylindrical gears are established based on meshing principle. The lubrication characteristics of arc tooth cylindrical gears under different injection methods and conditions are analysed by using computational fluid dynamics (CFD) model. The variation law of oil volume fraction in the gear‐meshing zone is obtained. Comparing the two oil jet methods in into mesh lubrication, when the ratio of the pitch line velocity to the injection velocity is less than 1.5 times, the best lubrication is gained through the concave surface injection method, when the ratio of the pitch line velocity to the injection velocity is more than 1.5 times, the best lubrication is gained through the convex surface injection method. It shows that the tooth shape has significant influence on lubrication when the lubricating oil is injected. [ABSTRACT FROM AUTHOR]

Producing lubricating base oils from coal‐based chemicals is an alternative route for replacing the conventional petro‐based lubricants. Herein, we firstly reported the synthesis of high‐viscosity polyalkylphenanthrene oils derived from the coal‐based chemicals (phenanthrene, C6/C8‐olefins) by alkylation with acidic ionic liquid (Et3NHCl∙2AlCl3) as catalyst. Their primary physicochemical properties were studied in detail to reveal their structure–property relationships, the existence of the phenanthrene ring in their molecular structure led to some good property, such as high‐kinematic viscosity (12.6–30.2 mm2·s−1 at 100°C), better flash point (>230°C), high‐oxidative onset time (>230°C) and good polarity. Moreover, the tribological performances of the synthetic oils and the commercial PAO‐20 lubricating base oil were studied for comparison, these alkylated phenanthrenes, especially PHP‐3 and POP‐3, exhibited much higher load‐carrying capacity, reducing friction and anti‐wear property than that observed on PAO‐20. [ABSTRACT FROM AUTHOR]

In this work, we showed that the mesoporous molecular sieve SBA‐15 could be used as an oil storage smart microcontainer to adsorb PAO6 oils and is prepared as an oil‐containing molecular sieve SBA‐15O, the compositing of SBA‐15O with unsaturated polyester resins (UPR) can significantly improve the lubrication properties of UPR. The oil‐containing molecular sieve SBA‐15O was prepared by vacuum impregnation and compounded into the UPR. The lubricating effect of different SBA‐15O contents on the UPR was investigated. As compared with the UPR, the coefficient of friction (COF) of the 10%SBA‐15O/UPR could be reduced to 10% of that without SBA‐15O, and the wear rate by three orders of magnitude. The results show that the improvement of lubricating performance is related to the release of lubricating oil from the microcontainer to the surface to produce a lubricating oil film during friction, thereby enhancing the self‐lubricating performance of the composite material. [ABSTRACT FROM AUTHOR]

In this work, TiO2 nanoparticles modified with octadecylamine and dodecyl mercaptan (DDM/ODA@PDA@TiO2 NPs) are uesd to improve the tribological properties of the white oil. The DDM/ODA@PDA@TiO2 NPs which are simply prepared by mussel inspired chemistry and the Michael addition reaction can be facilely dispersed in the white base oil. Tribological measurements showed that the dispersion of the white oil containing 3 wt% DDM/ODA@PDA@TiO2 NPs displays significant reductions in the friction coefficient and wear scar diameter at room temperature and 75°C. Further XPS investigation shows that the favourable tribological properties of DDM/ODA@PDA@TiO2 NPs are ascribed to the synergistic effect of tribofilm (Fe2O3, Fe3O4, FeS2, FeS and FeSO4) and TiO2 nanofluids. [ABSTRACT FROM AUTHOR]

Melt electrospinning is a convenient method for producing nonwoven materials from polymers with limited solubility, such as polyolefins and its blends. In this work, we investigated the process of electrospinning from melt of blends of thermodynamically immiscible polymers: polypropylene and polystyrene. Nonwoven materials with an average fiber diameter of 1.5–4 μm have been obtained. Typically, morphology of blended nonwoven material can be further modified by selective removal of one of the components. However, it was found that after removal of polystyrene from the produced materials, the fibers do not undergo significant changes in the surface morphology. At the same time, fiber fragments having a length of 5–100 μm appear and their number grows as the content of polystyrene in the initial material increases. According to X‐ray data, the supramolecular structure of polypropylene changes in the electrospinning process: a transition from a stable α‐form to a low‐ordered mesophase occurs. On the other hand, a reverse transition to crystallites of the α‐form of polypropylene was observed after polystyrene was removed with hot chloroform. All materials exhibit superhydrophobic properties and their wetting occurs according to the Wenzel model. Sorption capacity of the resulting materials is up to 90 g/g for motor oil. [ABSTRACT FROM AUTHOR]

Oily wastewater has caused serious damage to the ecological environment and became one of the main factors hindering the sustainable development of human society. Novel membrane materials are expected to be an effective way to solve the pollution due to its high separation efficiency. In this work, sepiolite (Sep), a natural inorganic clay material, was inserted into the adjacent MXene nanosheets, and a series of Sep@MXene/CA composite membranes were successfully constructed on the cellulose acetate (CA) commercial membrane through vacuum filtration method. The structure of nanomaterials and composite membranes were characterized by X‐ray diffraction and scanning electron microscopy. The permeability and selectivity of Sep@MXene/CA composite membranes for lubricating oil emulsion were investigated in detail. The results showed that the modified composite membranes exhibited better hydrophilicity compared with pure MXene/CA membrane, which presented pure water flux of 611.2 and 820.3 L m−2 h−1 bar−1, respectively. In addition, the rejection ratio of lubricating oil was more than 95%. This work provides a new approach for the modification of MXene membrane and makes Sep@MXene/CA membrane show a good application potential for the treatment of oily wastewater. [ABSTRACT FROM AUTHOR]

Good dispersion stability of lubricating oil blends added with graphene is the premise of playing its superior tribology property. In this paper, the dispersion stability of modified graphene in lubricating oil and the wear property of nanolubricating oil on the key friction pair for a diesel engine was studied by simulation and experiment. The results showed that the dispersion of modified graphene in lubricating oil was improved at ambient temperature and pressure and at high temperature and pressure. However, the dispersion effect of graphene at high temperature was slightly worse than that at ambient temperature. The wear property of lubricating oil blends added with modified graphene with a concentration of no more than 100 ppm was improved. With the increase of graphene addition, the wear reduction effect increased first and then decreased. The lubricating oil blend added with 25 ppm modified graphene is the best for wear reduction. [ABSTRACT FROM AUTHOR]

Porous mullite beads with a good spherical shape and a uniform size distribution of about 1.2 mm were fabricated by ice‐templating in combination with dripping methods. These internal pore structures exhibited a radially oriented laminar channel from the center of the sphere to the surface. With the decreasing of freeze temperature to −196°C, the thickness of pore walls and the width of pore decreased. The mullite grain morphology in the pore wall was also influenced by the frozen temperature. High aspect ratio mullite grain was formed in the pore wall of beads frozen at −25°C, while low aspect ratio mullite whiskers constituted the pore wall of beads frozen at −196°C. In addition, the obtained porous mullite beads exhibited a good oil adsorption performance under capillary force for kerosene, edible oil, and motor oil with adsorption values of 3.37, 4.07, and 4.04 g/g, respectively. [ABSTRACT FROM AUTHOR]

In this study, the kinetic of lipopeptide biosurfactant production by Bacillus subtilis LAMI005 and its tensoactive and emulsifier properties were evaluated. The influence of the concentrations of nitrogen ((NH4)2SO4) and carbon source (glucose and fructose) on biosurfactant production, using a mineral medium, were evaluated. A production of about 930 mg · L−1 of surfactin was observed for mineral medium supplied with total reducing sugars (16.55 g · L−1) and (NH4)2SO4 (1 g · L−1) as carbon and nitrogen sources, respectively. The crude biosurfactant exhibited its potential as tensoactive, presenting the capability to reach surface tension of about 28 mN ⋅ m−1 for water and exhibiting low CMC (~14–20 mg · L−1). The analysis of emulsifying activity showed a greater stability of emulsion formed in motor oil (3.5 U), soybean oil (2.0 U), and biodiesel (1.5 U). The emulsion formulated on motor oil remained stable for more than 200 h, which was explained by its average drop diameter (~0–10 μm). The surface‐active properties of surfactin did not seem to be affected by different NaCl concentrations, which may promote its applicability in high salt environments, such as oil spills in marine areas. [ABSTRACT FROM AUTHOR]

Inspired by the carnivorous Nepenthes pitcher plant, a range of highly liquid repellent lubricant‐infused surfaces has been devised (low water droplet contact angle hysteresis and sliding angle values). This entails matching functional pulsed plasma polymer nanolayers with appropriate slippery lubricants. A molecular‐level structure–behavior relationship is developed, highlighting the importance of favorable aromatic–aliphatic intermolecular interactions between the coating and lubricant. Fluorinated lubricant‐infused pulsed plasma polymer nanocoatings resist wetting by liquids, spanning a wide range of surface tensions (including pentane, motor oil, and water, i.e., omniphobicity). In the case of natural antimicrobial compound‐infused functional plasma polymer surfaces (e.g., the essential oil cinnamaldehyde), multifunctional performance is attained combining high liquid repellency (self‐cleaning) with simultaneous strong antibacterial activity against both Gram‐positive Staphylococcus aureus and Gram‐negative Escherichia coli (log10 reduction > 7). In addition, these lubricant‐infused functional pulsed plasma polymer surfaces easily repel a variety of everyday liquids (including foodstuffs such as tomato ketchup and honey). [ABSTRACT FROM AUTHOR]

Rationale: The efficiency of lubricants strongly depends on the content of functional additives. In order to assess the chemical and structural changes taking place in the lubricating oil and its additives during operation, it is essential to develop a method for simple and prompt analysis. Methods: Two single additives as well as a fully formulated engine oil were analysed using an atmospheric pressure matrix-assisted laser desorption/ionization (AP-MALDI) source coupled to a linear trap quadrupole Orbitrap XL hybrid tandem mass spectrometer and compared with results obtained by means of electrospray ionization (ESI) including additional low-energy collision-induced dissociation (LE-CID). The identification of additives directly from technical surfaces was simulated by using steel substrates as AP-MALDI targets with varying roughness. Results: After assessment and selection of the most suited AP-MALDI matrix it was found that pure additives such as calcium sulfonate and zinc dialkyldithiophosphates (ZDDPs) could well be identified with abundant signal intensity based on their elemental composition. Molecular identification was corroborated by LE-CID in ESI mode. Additionally, additives present in the fully formulated commercial oil such as ZDDPs and salicylates could be reliably identified based on the elemental composition of the deprotonated molecules by means of the Orbitrap unit on different substrates including steel surfaces with high roughness. Conclusions: AP-MALDI is an efficient technique for determination of lubricant additives directly from commercial oil blends. Identification of additive components was also achieved on steel surfaces with high roughness as applied in tribological systems and thus it is expected that it will be possible to assess additive degradation in real applications, enabling more effective and timely maintenance measures. [ABSTRACT FROM AUTHOR]

Intelligent lubricating materials can control the coefficient of friction between interfaces in response to external stimuli. Considering that mechanical transmission parts are mostly used in oil‐based lubrication environments, the lubrication performance and electrical regulation mechanism of poly‐α‐olefin‐50 (PAO50), a lubricating oil, containing 1‐octyl‐3‐methylimidazolium hexafluorophosphate ([OMIm]PF6), an ionic liquid (IL), are investigated in this study. Friction tests on a universal micro‐tribometer under current stimulation show that ionic lubricating oil has an excellent lubrication performance and electrical responsiveness. By changing the current strength, ion content, and the load, the reasons behind the change in the coefficient of friction are investigated. Ion aggregation results in an increase in the viscosity of the lubricating oil film, which leads to an increase in the coefficient of friction. Moreover, the real‐time resistance value of the oil film is obtained through a self‐built voltage acquisition device. The mechanism of the electronic control of friction is verified by analyzing the influence of the change in ion distribution on the resistance of the oil film. There is a correlation between the resistance and viscosity of the oil film. The results of this study may be significant in guiding research on the intelligent control of friction under oil‐based lubrication. [ABSTRACT FROM AUTHOR]

The aim of this work was to optimize the production of a new lipase by a halotolerant bacterial strain Halomonas sp. C2SS100, by means of the response‐surface methodology (RSM). The process parameters having the most significant effect on lipase production were identified using the Plackett–Burman screening design‐of‐experiments. Then, Box–Behnken design was applied to optimize lipase activity and the quadratic regression model of the lipase production was built. Indeed, the lipase yield was increased, and the value obtained experimentally (39 ± 2 U/ml) was very close to the rate predicted by the model (40.3 U/ml). Likewise, optimization of parameters by RSM resulted in 2.78‐fold increase in lipase activity. These findings provide the first report on lipase production and optimization by a halotolerant bacterial strain belonging to Halomonas genus. Afterward, the biochemical properties of the produced lipase were studied for apply in oil stains removal. The crude lipase showed a maximum activity at 60°C and at pH ranging from 7 to 10. It displayed an important stability at high temperature, pH, and NaCl. Interestingly, this bacterial lipase exhibited a prominent stability toward some commercial solid and liquid detergents after 30 min of incubation at 50°C. The capability of the crude lipase to eliminate stain was ascertained on polycotton fabric pieces stained with lubricating oil. Whether with the addition of hot water alone or of a commercially available detergent, lipase is able to considerably boost the elimination of oil stains. The actual findings highlight the capacity of Halomonas sp. lipase for energy‐efficient biocatalytic application. [ABSTRACT FROM AUTHOR]

Previous research has emphasized the importance of product packaging to consumers' attitudes and purchase intentions, but empirical studies that explore the specific mechanisms by which packaging color influences marketing‐relevant downstream variables in relation to environmentally friendly products is scarce. The current research addresses this gap by building on insights from theories on consumption values, gender roles, and gendered products. In two studies, the current research shows (1) how color‐induced perceptions of masculinity can trigger perceived product effectiveness and purchase intentions, (2) how competing mediation through masculinity and perceived fit with the product category influences perceived product effectiveness and purchase intentions for green products, and (3) that the positive influence of masculinity on perceived product effectiveness holds for male but not female consumers. These effects occur independently of color saturation and product positioning for two different product categories where strength and durability are relevant: washing detergents (Study 1) and motor oil (Study 2). The results of this research add a novel and differentiated perspective on the effects of color and gender roles in the context of environmentally friendly consumption and provide marketing managers with suggestions on how to increase perceived product effectiveness and purchase intentions related to green products. [ABSTRACT FROM AUTHOR]

Lubricating greases were investigated by nuclear magnetic resonance/magnetic resonance imaging (NMR/MRI) to get insight into their structure and into their response to mechanical forces, which is related to bleeding and aging. The investigated greases are based on metallic soaps of fatty acids and oils, whereby LiOH is often used. These organic soaps act as thickeners and provide a network in which oils and their additives are embedded. Lubricating greases can thus be considered as a class of substances similar to oleogels or even hydrogels. Questions arise about translational mobility of guest molecules, mainly base oil, in these networks. Molecular structuring and interactions within the network of thickeners are of interest as they are related to macroscopic stability. Apart from NMR spectroscopy (1H‐, 7Li‐ and 31P‐NMR), spectrally resolved relaxation and diffusion measurements are used for characterization. In addition, magic angle spinning (MAS)‐NMR was combined with 1H‐MRI to investigate the impact of mechanical stress and swelling of lubricating greases. [ABSTRACT FROM AUTHOR]

The performances of diesel cylinder liner‐piston ring (CLPR) that works under harsh conditions are very important and affect the service life, reliability and economy of engines. This study aimed to gain insights into the anti‐friction and self‐repairing properties of lubricating oil with different silicate‐based additives for marine diesel CLPR, and expect to find the types and concentrations of additives that are most appropriate for CLPR. Three kinds of silicates, including ultrafine serpentine, attapulgite and kaolin powders, were prepared and modified, and added to the lubricants with different concentrations. The tribological behaviours and worn surface features of the friction pairs were investigated after friction tests. Compared with original oil, it is found that all additives process anti‐friction and self‐repairing properties at appropriate concentration, and the ultrafine attapulgite powders additive presents the best performance. These findings will aid in understanding the anti‐friction and self‐repairing abilities of silicate‐based additives to diesel CLPR, as well as its potential application to solve the wear failures of CLPR online. [ABSTRACT FROM AUTHOR]

The dynamism of the reliability of machines and equipment has the objective of availability, leading to the development of several techniques of predictive maintenance, to define the ideal point for the intervention. Among the several predictive techniques, the analysis of lubricants has its highlight. In this sense, lubricants are used to reduce friction and wear between two interacting surfaces, filling the space of surface imperfections. In this way, wear is common even with the use of lubricating oils on the interacting surfaces. Thus, an artefact for ascertaining the wear particles by size in lubricating oils is analytical ferrography. In this way, this work presents the development of a low cost rotary separator prototype to obtain ferrograms, through five distinct combinations of permanent magnets and electronic devices. Several combinations of magnets were used and it was concluded that the 03, 04, and 05 combinations showed a better formation quality of ferrous wear particle rings. In addition, only two rings were formed in the 04 combination, but this was the best combination by size separation. [ABSTRACT FROM AUTHOR]