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N-doped graphene oxide quantum dots (NGOQDs) with MoS2 and Al2O3 nanocomposites were prepared by solvothermal method. The morphology and the composition and structure of the prepared composites were characterized by TEM, XRD, Raman, ATR-FTIR, and XPS. Tribological behavior of NGOQDs-MoS2 and NGOQDs-Al2O3 nanocomposites as lubricant additive in aqueous glycerol were studied. Through experiments and MD simulations, the tribochemistry-induced lubrication mechanism was disclosed. The results shows that the combination of NGOQDs and hydrated glycerol can significantly improve lubrication performance, and the addition of NGOQDs-MoS2 and NGOQDs-Al2O3 nanoparticles can further improve tribological properties. The formation of a tribofilm through tribochemical induced lubrication mechanism improves the wear resistance of metal surfaces. [ABSTRACT FROM AUTHOR]

Nano-BN/Si and BN/Al2O3 composite lubricants was prepared by a hydrothermal stirring synthesis method. Orthogonal experiments were conducted by changing the mass fraction of Si and Al2O3. The extreme pressure and wear resistance performance of nano-BN lubricants were investigated using the four-ball machine method. The effect of nano-BN on the friction and wear performance of AlN plates was studied using multifunctional friction and wear tests. SEM, EDS, and XPS were used to characterize the wear morphology and element distribution on the wear surface of the steel balls and the sliding AlN plates. The wear and friction mechanism of nano-BN/Si and BN/Al2O3 as anti-wear additives contained in the nano-composite lubricants between the metal friction pairs were proposed. The excellent tribological performance of the BN composite lubricants is attributed to the synergistic effect between nano-Si particles or Al2O3 particles and layered nano-BN particles. This accelerates the formation of solid lubrication film composed of BN, Si, Al2O3, and Fe2O3 on the surface of the AlN plate, thus reducing the wear between friction pairs. [ABSTRACT FROM AUTHOR]

The powders of hBN, SiC, and B4C were employed as the raw ingredients to prepare the B4C–SiC–hBN composite ceramics by a vacuum high-pressure sintering method with hBN and SiC contents in the range of 0, 10, and 20 wt.%, respectively. A pin-on-disc testing equipment was used to assess the tribological properties of B4C–SiC–hBN composite ceramics with various hBN and SiC content when sliding against AISI 347 steel immersed in the emulsion. The experiment's findings indicate that the sliding COF of the B4C/AISI 347 steel pair marginally drops as the sliding distance increases. Besides, the sliding COF of the B4C–10 wt.% SiC–20 wt.% hBN/AISI 347 steel pair rapidly declines. By tribopairs of B4C–SiC–hBN composite ceramics against AISI 347 steel under the condition of lubrication by water-based emulsion, the steady-state friction may move into a state of mix lubrication as the hBN concentration rises, improving the tribological performance. The steady-state COF considerably decreases to 0.01 from 0.386 as the hBN and SiC concentration is increased to 20 wt.% and 10 wt.% from zero, showing a decreasing trend for both the B4C–SiC–hBN pin and AISI 347 steel disc samples' COWs. The steady-state friction of tribopairs of B4C–SiC–hBN composite ceramics against AISI 347 steel may enter a state of mixed lubrication in the emulsion. The wear resistance of composite ceramics was improved by the addition of hBN and SiC particles because of their lubricating and reinforcing effects. These findings offer valuable insights into the design and development of advanced composite ceramics for various industrial applications that require improved tribological properties. [ABSTRACT FROM AUTHOR]

WO3:Eu3+ powder was prepared by microemulsion method with cetyltrimethyl ammonium bromide (CTAB) as a surfactant. The prepared WO3:Eu3+ samples were wrapped with SiO2 by a coating method. The WO3:Eu3+@ SiO2 nanocomposites with the core-shell structure were prepared by controlling tetraethyl orthosilicate (TEOS) content (1, 3, 5 and 7%) and water–alcohol ratio (1:3, 1:1.5, 1:1 and 2:1). The structure, morphology and luminescence properties of the prepared WO3:Eu3+@ SiO2 samples were characterized by XRD, SEM, TEM and fluorescence spectra. The results show that the prepared WO3:Eu3+@SiO2 nanocomposites are spherical and granular, and the average particle size is below 100 nm. Under the condition of different TEOS contents, the strongest characteristic peak is located at 554 nm in the green light band at the excitation wavelength of 328 nm. Among the different water–alcohol ratio conditions, the prepared WO3:Eu3+@SiO2 nanocomposite has the strongest luminescence intensity at the water–alcohol ratio of 1:3, and the excitation wavelength is 328 nm. The excitation spectra measured at 612 nm have prominent characteristic peaks at 362, 394, 422, 465 and 499 nm, which correspond to the transition of 7F0→5D4, 7F0→5L6, 7F0→5D3, 7F0→5D2 and 7F0→5D1, respectively. [ABSTRACT FROM AUTHOR]

Tungsten trioxide (WO3) nanoparticles were prepared by the citric acid method, using ammonium paratungstate as the tungsten source, and doped with rare earth europium (Eu) under various pH values and Eu content. The microstructure, morphology, and luminescence properties of the prepared samples were characterized by XRD, SEM, and a fluorescence spectrometer. The results show that Eu3+ doped WO3 nanoparticles were successfully obtained by the citric acid method, the prepared nanoparticles were spherical and rhomboidal, and the average particle size of the prepared samples reached 56 nm. The excitation spectrum consisted of a series of linear excitation peaks in the range of 250–550 nm. The strongest excitation peak was located at 543 nm, which belongs to the 7F0 → 5D1 transition of Eu3+. [ABSTRACT FROM AUTHOR]

Purpose: WO3 particles were prepared by the sol-gel method. Tetraethyl silicate (TEOS) was used to obtain a SiO2-coated WO3 nanoparticle. Quantum chemical parameters of oleic acid, triethanolamine, glycerol and methyl pentane as dispersants were theoretically calculated. Tribological properties of SiO2/WO3 nanocomposite lubricant were carried out on an MRS-10A four-ball friction and wear tester. Design/methodology/approach: The purpose of this study is to investigate the preparation and tribological properties of SiO2/WO3 nanocomposite lubricant. Findings: The obtained SiO2-coated WO3 nanoparticle (nano-SiO2/WO3) with a particle size of about 70 nm. The calculated adsorption energy of triethanolamine on the surface of the steel ball is 554.6 eV, and triethanolamine is selected as the dispersant. The dispersion effect of SiO2/WO3 nanocomposite lubricant is good, which shows that triethanolamine oleate plays a good dispersion role in the preparation of lubricant, which is consistent with the calculation results of the adsorption capacity of dispersant. As a good auxiliary lubricant, SiO2 can improve the tribological properties and wear resistance of WO3. Originality/value: Nanocomposite lubricants have been the focus of research in recent years, which could greatly reduce energy consumption. And the SiO2/WO3 exhibited excellent lubrication performance as a lubricant additive. The lubrication mechanism of SiO2/WO3 nanocomposite lubricant is the synergistic lubrication mechanism of friction film lubrication and antifriction bearing. This study could provide a certain reference for the practical application of nanocomposite lubricants. [ABSTRACT FROM AUTHOR]

Eu-doped WO3 (WO3:Eu3+) nanoparticles were prepared by the Pechini method. Tetrabutyl titanate (TBOT) was used to prepare TiO2-encapsulated WO3:Eu3+ nanoparticles (TiO2@WO3:Eu3+). Microstructure and morphology of the prepared nanoparticles were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM). The results show that the mean diameter of the TiO2@WO3: Eu3+ nano powder prepared at pH = 10 is the smallest, up to 50 nm. The tribological properties of the TiO2@WO3:Eu3+ as extreme pressure and wear resistance agents in water-based lubricant were investigated by a four-ball machine. The results showed that TiO2@WO3:Eu3+ exhibits excellent load-carrying capacity, anti-wear, and anti-friction properties in water-based lubricant, especially when the concentration of TiO2@WO3:Eu3+ was 0.4 wt%. The average wear scar diameter (WSD) was decreased from 0.62 to 0.34 mm and the coefficient of friction (COF) was reduced from 0.0721 to 0.053. This is mainly because of the formation of tens of nanometers thick tribofilm, the actual contact between metals is prevented. [ABSTRACT FROM AUTHOR]

Nano-WO3:EU3+ powder was prepared by Pechini method under acidic and alkaline condition, and the prepared acidic nano-WO3:Eu3+ mixed with the silver nanowires (AgNWs) in ethanol and acetone solution. The solution was mixed with PMMA and EP, respectively. Then, drops of the solutions were added to the indium tin oxide (ITO) conductive glass as the substrate; a AgNWs/WO3:Eu3+ composite film was obtained with spin coating by spin coater and solidification process. Microstructure, morphology, optical properties, preparation process and UV transmittance of the prepared nano-WO3:Eu3+ and AgNWs/WO3:Eu3+ composite films were investigated by XRD, SEM, fluorescence spectroscopy and UV spectrophotometer. The results show that the prepared acidic nano-WO3 is triclinic, and the average particle size is 71.63 nm. The prepared alkaline nano-WO3 is monoclinic, with an average particle size of 95.66 nm. Both of them have good luminescence properties. Under different monitoring wavelengths, in the emission range of 450–500 nm, it belongs to the green light region, and its excitation peak is the largest, indicating that green light is the best excitation light source for WO3:Eu3+ powder. The transmittance of EP/AgNWs/WO3:Eu3+ composite film is the highest when the spin coating time is more than 30 s and above 3000 rpm, no more than three layers spin coating and the content of curing agent is between 0.1 and 0.2 g. [ABSTRACT FROM AUTHOR]

Chambersite (Mn3B7O13Cl) precursor was prepared by the citric acid method, sodium borate dehydrate was used as a boron source, modified by cetyl trimethyl ammonium bromide (CTAB) as a surfactant, and its pH value was adjusted to 5 by ammonia. Mn3B7O13Cl nanoparticles were prepared by sintering at 500, 560, 600, and 650°C, respectively, and then ground by mortar. The microstructure, surface morphology, and luminescent properties of the prepared nano-Mn3B7O13Cl samples were analyzed by XRD, SEM, and fluorescence spectrometer. The effect of sintering temperature on the synthesis of manganese nano-Mn3B7O13Cl powder was studied. The prepared nano-Mn3B7O13Cl samples are spherical particles with irregular edges. When the sintering temperature is 650°C, the size of nanoparticles is the smallest, with an average size of 35 nm. When the excitation wavelength is 450 and 460 nm, the emission spectra of the nano-Mn3B7O13Cl samples prepared at different sintering temperatures have two emission peaks. There is a green emission peak at 550 nm and a red emission peak at 652 nm. When the excitation wavelength is 470, 480, and 490 nm, the emission spectra of the nano-Mn3B7O13Cl samples at different sintering temperatures have an emission peak in the range of green light band at 567, 589, and 601 nm, which is different from that at 450 nm and 460 nm. Under different excitation wavelengths, the emission peak intensity of the prepared nano-Mn3B7O13Cl samples sintered at 560°C is the highest, and the luminescence performance is better. The lowest emission peak and luminescence properties of the nano-Mn3B7O13Cl samples sintered at 500°C were studied. The excitation peak in the green band shifts to the orange band with increased excitation wavelength. The luminescence of the nano-Mn3B7O13Cl samples prepared at different sintering temperatures is the 4T1–6A1 transition of Mn2+ ion. [ABSTRACT FROM AUTHOR]

Genetic function approximation (GFA) algorithm was used to model the quantitative structure–activity relationship (QSAR) among corrosion inhibition efficiency, friction coefficient and oil film strength of the thiadiazole derivatives as corrosion inhibitor and antiwear and friction-reducing agent. Corrosion inhibition efficiency, friction coefficient and oil film strength of these compounds on the steel surface contained in the emulsion were studied by weight loss test and a fourball friction and wear test. The results show that quantum descriptors are a better choice for predicting the corrosion inhibition efficiency, friction coefficient and oil film strength of lubricants. For the thiadiazole derivatives, friction coefficient of the lubricants is inversely proportional to their inhibition efficiency and oil film strength. [ABSTRACT FROM AUTHOR]

Tungsten oxide is widely used in the photolysis of water for hydrogen production, photocatalysis, photoelectric conversion, and electrochromism. Eu3+ doped tungsten trioxide nanoparticles were prepared by hydrothermal method with the addition of sodium tungstate (NaWO4 · 2H2O). Two different samples were obtained at the temperature set at 160 and 180°C. The third sample obtained from ammonium paratungstate ((NH4)10H2(W2O7)6) was used at the temperature of 160°C. The samples' morphology, structure, and optical performance were then observed and analyzed. The results show that a rod-like structure of WO3 : Eu3+ nanoparticle with a monoclinic crystal system can be successfully generated using sodium tungstate. A spherical structure of WO3 : Eu3+ nanoparticle with a triclinic crystal system was prepared using ammonium paratungstate. The finished sample with ammonium paratungstate at a reaction temperature of 160°C has the smallest grain average size of 45.98 nm and Eu3+ ions successfully doped. Under the excitation of different wavelengths, the three samples demonstrate pronounced emission peaks at around 615 nm, corresponding to the 5D0 → 7F2 electronic transition of Eu3+. Using ammonium paratungstate as the tungsten source, the prepared WO3 : Eu3+ nanoparticle at 160°C has the highest luminous intensity. The luminescence intensity of the prepared WO3 : Eu3+ nanoparticle from ammonium paratungstate as a tungsten source is higher than the other two samples obtained from sodium tungstate as a tungsten source at two temperatures. However, the three samples with excitation wavelength λ = 254 nm were monitored at the wavelength of 615 nm. All three samples exhibited the most substantial excitation peaks at about 508 nm, which belonged to the electron transition in 4f of Eu3+. [ABSTRACT FROM AUTHOR]

CaWO4 and WO3 nanoparticles were prepared by the sol-gel method and Pechini method. The morphology and structure of nano-CaWO4 and nano-WO3 were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Tribological, hot forming, and hot rolling lubrication properties of nano-CaWO4, nano-WO3, and mixed nano-CaWO4-WO3 as antiwear additives in water-based fluid were investigated using a four-ball friction and wear testing machine, Gleeble tester, and two-high rolling mill, respectively. Results showed that 0.3 wt% mixed nano-CaWO4-WO3 has excellent tribological properties in water-based fluid. The average wear scar diameter values decreased from 0.62 to 0.37 mm (mixed WO3-CaWO4) and the coefficient of friction value reduced from 0.080 to 0.064. This was due to the formation of a tribofilm (∼30 nm) on the worn surface during the forming process, avoiding direct contact between the metals. During Gleeble hot forming, the lubrication effect of the mixed nano-CaWO4-WO3 was the best. The nano-WO3-CaWO4 particles were relatively dispersed and dis not bond together under high temperature and pressure conditions, which played a role in reducing friction resistance between friction pairs. With the addition of 0.3 wt% mixed WO3-CaWO4 nanofluid, the surface quality was improved and it had the lowest surface roughness in the hot rolling process. [ABSTRACT FROM AUTHOR]

CaWO4: Eu3+ nanoparticles in acidity (pH = 5) and alkalinity (pH = 10) solutions were prepared by citric acid method, and characterised by SEM and XRD. Tribological behaviour and lubrication performances of nano‐CaWO4:Eu3+ as extreme pressure (EP) additives in water‐soluble fluid for laminated copper cladding steel sheet during cold rolling were studied. These results suggest that CaWO4:Eu3+ exhibits excellent extreme pressure property, antiwear and antifriction performances in water‐soluble fluid, especially when the optimal concentration was 0.3 wt%. The value of WSD reduced from 0.62 to 0.40 mm and the value of COF decreased from 0.078 to 0.068, the surface quality of rolled sheet is improved with the addition of nano‐CaWO4:Eu3+ (pH = 5 and pH = 10), because the tribofilm (~20 nm) composed of Fe2O3, WO3, Eu2O and CaO was formed on the worn surface to avoid direct contact between metal friction pairs in sliding process. [ABSTRACT FROM AUTHOR]

0.2, 1.0, and 2.0 wt.% concentration of molybdenum disulfide (MoS2) nanoparticles were dispersed in mineral and synthetic ester base oil. Their tribological behavior investigated using a tribometer with pin-on-disk and four-ball configuration under different conditions of contact pressures, sliding speeds and oil bath temperatures, respectively. The results demonstrate that nano-MoS2 in mineral oil can reduce wear and friction coefficient characteristics at all concentrations tested, especially at 2.0 wt.%. XPS analysis of the worn surfaces indicated that decomposed MoS2 was adsorbed on worn surface, and S and Mo elements of the compound reacted with the metal and existed in the form of sulfide or molybdenum compounds, both of which contributed to the formation of a mix lubricating film. A wear mechanism of MoS2 as antiwear additive is proposed. [ABSTRACT FROM AUTHOR]

Two imidazole derivatives, 2‐(2‐((benzo[d]thiazol‐2‐ylthio)methyl)‐4,5‐dihydro‐1H‐imidazol‐1‐yl)ethan‐1‐ol (BTM) and 2‐(2‐((1H‐benzo[d][1,2,3]triazol‐1‐yl)methyl)‐4,5‐dihydro‐1H‐imidazol‐1‐yl)ethan‐1‐ol (BTMS), as a new corrosion inhibitor were synthesized, and their inhibition behaviors for mild steel contained in emulsion were investigated by gravimetric experiment, electrochemical tests, and theoretical calculations. The results show that the inhibition effect of BTMS is better than that of BTM, the maximum value of the inhibition efficiency reaches 97.9%. The resultant adsorption films from BTM/BTMS adsorbed on mild steel, effectively inhibiting the corrosion of mild steel is mainly through chemisorption and follow to Langmuir's adsorption isotherm. [ABSTRACT FROM AUTHOR]

Citric acid‐synthesised Eu‐doped WO3 (WO3:Eu3+) and Mn3B7O13Cl nanoparticles were characterised by X‐ray diffraction and transmission electron microscopy. The tribological properties of the Eu doped WO3 and Mn3B7O13Cl prepared as anti‐wear additives for enhanced lubrication were studied using a four‐ball tester. The experiment results indicated that Eu doped WO3 nanoparticle reinforce Mn3B7O13Cl has excellent load‐carrying capacity, wear‐resistance and friction‐reducing properties in water‐based lubricant, optimum concentration of WO3:Eu3+‐Mn3B7O13Cl was 0.5 wt%. The wear scar diameter decreased from 0.62 to 0.37 mm and the coefficient of friction was reduced from 0.083 to 0.065, which reductions are attributed to the nanotribofilms composed of B2O3, WO3, Fe2O3 and Eu2O, which prevented direct contact between metals. Hot rolling experiments of laminated Cu‐Fe composite sheet were carried out to study the effect of nano‐WO3:Eu3+‐Mn3B7O13Cl on surface qualities including topography of rolled strips. Results show that the surface topography becomes smooth with the addition of nanoparticles into water‐based lubricant, which is mainly attributed to the nanoparticles increase the viscosity of water‐based lubricant and the oil film to avoid the direct contact tribopair during hot rolling, thus reducing the friction coefficient and roll wear. [ABSTRACT FROM AUTHOR]

Eu-doped WO3 (WO3:Eu3+) nanoparticles were prepared by Pechini method under different pH values (pH 1, 3, 5, and 7). The prepared nano-powders were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM). The results showed that the average external diameter of the prepared nano-WO3:Eu3+ powders is the smallest and reaches 50 nm at pH 5. Structural transformation matrix contained different crystals of anorthic and orthorhombic structures. Eu3+ ions are located at the center of the non-inversion symmetry of WO3:Eu3+. The tribological properties of the WO3:Eu3+ as extreme pressure and wear resistance agents in water-based lubricant were investigated by a four-ball machine. The results showed that WO3:Eu3+ displays excellent load-carrying capacity, wear resistance, and friction-reducing properties in water-based lubricant, particularly in the best concentration of WO3:Eu3+ was 0.6 wt%. WSD was reduced from 0.62 to 0.35 mm and COF was decreased from 0.083 to 0.055. This was due to the formation of tribofilms with a few tens of nanometers thick, which prevented no actual metal-to-metal contact. [ABSTRACT FROM AUTHOR]

For the development of national industry green environmental protection, the use of zinc dialkyl dithiophosphate (ZDDP) should be reduced in the process of mechanical lubrication, two novel borate esters, SS-(5-disulfanyl-1,3,4-thiadiazol-2-yl) O-(6-stearoyl-1,3,6,2-dioxazaborocan-2-yl) carbono(dithioperoxoate) (BNSD) and 6-stearoyl-1,3,6,2-dioxazaborocan-2-yl stearate (BNCD), were synthesized and characterized by FT-IR and TGA. Tribological performance of ZDDP, BNSD and BNCD as a multifunctional additive in synthetic ester base oil were investigated under different loads using a MR-S10 four-ball and MFT-3000 friction and wear test machine. A scanning electron microscope and laser scanning confocal microscope were used to observe worn scar surface morphology of the balls. The chemical compositions of worn surface were analyzed by X-ray photoelectron spectroscopy and the tribofilm of the worn surface was observed by transmission electron microscope. The TGA curves showed that BNSD and BNCD had a better thermal stability than ZDDP. BNSD exhibits excellent anti-wear and friction-reducing properties, the PB value is increase to 784 N when the optimized concentration is 0.3% the minimum WSD of BNSD-based lubricant is approximately 0.52 mm and decreased by 35% compared with the base oil. A protective tribofilm of the ball steel was analyzed by XPS and TEM, which revealed that B2O3 and Fe2B constitute the triboilm and about 5 nm. Therefore, BNSD could be a candidate as anti-wear and friction-reducing agent in lubricants instead of ZDDP. [ABSTRACT FROM AUTHOR]

The Mn3B7O13Cl nanoparticle (~30 nm) has been prepared by sol‐gel method and characterised by powder X‐ray diffraction (XRD) and transmission electron microscopy (TEM). The tribological properties of prepared Mn3B7O13Cl nanoparticle and the common nano‐Cu and nano‐Fe nanoparticles as antiwear additives with various concentrations in polyalphaolefin (PAO) base oil have been investigated. PB values of nano‐Mn3B7O13Cl added oil are superior to base oil, nano‐Cu and nano‐Fe added oil with the same content, and it reaches the value of 637 N. The wear scar diameter is 0.52 mm when the concentration is only 0.2 wt.%. And meanwhile, Mn3B7O13Cl nanoparticle as efficient antiwear lubricant and commercial oil was measured in the sliding wear between tantalum strip and 52100 bearing steel ball by MFT‐3000 friction and wear tester at an optimised additive concentration (0.2 wt.%). Coefficient of friction of tantalum strips is reduced by 41.5% compared with that of the commercial oil. Surface morphology studies and X‐ray photoelectron spectroscopy (XPS) analysis have revealed that the prominent tribological behaviour of Mn3B7O13Cl was caused by the formation of ~ 30‐nm tribofilm made of adsorbed boron and tribosintered nano‐Mn3B7O13Cl. Therefore, Mn3B7O13Cl nanoparticle has a potential to develop as friction‐reducing and antiwear lubricant in the sliding wear between tantalum strips and steel ball to avoid the severe wear. [ABSTRACT FROM AUTHOR]

A nano-Mn3B7O13Cl crystal was synthesized by a sol–gel method, and the structure, morphology and size were characterized by X-ray diffraction, scanning electron microscopy (SEM) and transmission electron microscopy. Effects of gamma radiation on the microstructure, luminescence properties, and medical performance for Mn3B7O13Cl have been discussed. The results show that Mn3B7O13Cl nanocrystals are uniform, and the average crystal size is about 50 nm. Under the 202 Gy measurement of gamma-ray irradiation, there are a large number of crystal defects in a chambersite crystal, and the defect is given priority with point defects and dislocations especially in gamma-ray irradiation with high energy. The luminescence intensity of natural chambersite in red light wavelengths increased obviously, and the luminescence intensity increased by 3.5 times. Nano-Mn3B7O13Cl exhibited the most significant antitumor activity and antiseptic effects. The best inhibition concentration of natural chambersite to A549 is 100 µg/ml, and its inhibition rate reaches 80%. Addition of natural chambersite in the solution significantly lowers the concentrations of Escherichia coli BL21, and the value is reduced by 97.6%. Therefore, chambersite has important application in the field of medical and shielding materials. [ABSTRACT FROM AUTHOR]

Sliding friction of copper foil surface, which was exposed to bis (6‐acetyl‐1,3,6,2 ‐dioxazaborocan‐2‐yl) methyl phosphate (NEPB) as extreme‐pressure/antiwear agent in base oil while rubbing by a ferroalloy disk under high load, was explored in a multi‐specimen test machine to investigate the wear mechanism of NEPB on thin film lubrication. The results reveal that NEPB reduces the friction coefficient to ~0.16 at normal load of 200 N, and it has better antiwear and friction‐reducing property than the common copper oil. Ferroalloy against copper foil is along the Cu (111) direction, and the friction coefficient decrease relies on the spontaneous formation of chemically nanolayered tribofilm (approx. 30 nm) during sliding wear. The size of wear debris arranges from 6 nm to submicron. Decomposed borate esters and organic nitrides were adsorbed on the worn surface and P element of NEPB as extreme‐pressure/antiwear agent reacted with Cu and existed in the form of phosphates, both of which contributed to the formation of boundary lubricating film. [ABSTRACT FROM AUTHOR]

Although there have been notable improvements in treatments against cancer, further research is required. In colon cancer, nearly all patients eventually experience drug resistance and stop responding to the approved drugs, making treatment difficult. Steroid receptor coactivator (SRC) is an oncogenic nuclear receptor coactivator that serves an important role in drug resistance. The present study generated a doxorubicin‑resistant colon cancer cell line, in which the upregulation/activation of SRC was responsible for drug resistance, which in turn activated AKT. Overexpression of receptor tyrosine kinase‑like epidermal growth factor receptor and insulin‑like growth factor 1 receptor also induced SRC expression. It was observed that doxorubicin resistance in colon cancer also induced epithelial to mesenchymal transition, a decrease in expression of epithelial marker E‑cadherin and an increase in the expression of mesenchymal markers, including N‑cadherin and vimentin. Additionally, the present study indicated that SRC acts as a common signaling node, and inhibiting SRC in combination with doxorubicin treatment in doxorubicin‑resistant cells aids in reversing the resistance. Thus, the present study suggests that activation of SRC is responsible for doxorubicin resistance in colon cancer. However, further research is required to understand the complete mechanism of how drug resistance occurs and how it may be tackled to treat patients. [ABSTRACT FROM AUTHOR]