Knowledge

Welcome to our knowledge centre. Here you can find a selection of resources and articles on our products and industries we are involved with.

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Spotlight Paper

The Influence of Slide–Roll Ratio on the Extent of Micropitting Damage in Rolling–Sliding Contacts Pertinent to Gear Applications

This paper provides new understanding of the tribological mechanisms that drive the occurrence of micropitting damage. EHD film thickness measurements …

This paper provides new understanding of the tribological mechanisms that drive the occurrence of micropitting damage. EHD film thickness measurements were clearly able to show that increased micropitting damage resulting from higher slide roll ratios was not caused by a significant reduction if lubricant film thickness, questioning many of the assumptions currently being made to assess and predict micropitting damage in gears.

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Spotlight Paper

Study of Permanent Shear Thinning of VM Polymer Solutions

Using the unique features of the USV, researchers were able to clearly quantify the permanent shear thinning of high molecular …

Using the unique features of the USV, researchers were able to clearly quantify the permanent shear thinning of high molecular weight polymer solutions.  Further investigations using a standard GPC process (gel permeation chromatography) revealed that the polymer breakdown process is very different at low and high polymer concentrations. The paper finally put to rest the argument whether it is the applied shear rate or shear stress which determines shear thinning (spoiler alert: it’s the shear stress…).

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Spotlight Paper

Cooperativity Between Zirconium Dioxide Nanoparticles and Extreme Pressure Additives in Forming Protective Triboflms: Toward Enabling Low Viscosity Lubricants

Cutting edge MTM nanoparticle research carried out at the highly respected Carpick laboratory. The paper showed how relatively large nanoparticle …

Cutting edge MTM nanoparticle research carried out at the highly respected Carpick laboratory. The paper showed how relatively large nanoparticle of Zirconium dioxide (ZrO2), combined with organic capping ligands can form robust tribofilms under a wide range of contact conditions. Impressively significant   wear reduction was also reported when the nanoparticles were blended in commercial formulations.

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Paper

Surface Adsorption and Lubrication Properties of Plant and Dairy Proteins: A Comparative Study

The aim of this work was to compare the surface adsorption and lubrication properties of plant and dairy proteins. Whey …

The aim of this work was to compare the surface adsorption and lubrication properties of plant and dairy proteins. Whey protein isolate (WPI) and pea protein isolate (PPI) were chosen as model animal and plant proteins, respectively, and various protein concentrations (0.1–100 mg/mL) were studied with/without heat treatment (90 °C/60 min). Quartz crystal microbalance with dissipation monitoring (QCM-D) experiments were performed on hydrophilic (gold) and hydrophobic polydimethylsiloxane (PDMS) sensors, with or without a mucin coating, latter was used to mimic the oral surface. Soft tribology using PDMS tribopairs in addition to wettability measurements, physicochemical characterization (size, charge, solubility) and gel electrophoresis were performed. Soluble fractions of PPI adsorbed to significantly larger extent on PDMS surfaces, forming more viscous films as compared to WPI regardless of heat treatment. Introducing a mucin coating on a PDMS surface led to a decrease in binding of the subsequent dietary protein layers, with PPI still adsorbing to a larger extent than WPI. Such large hydrated mass of PPI resulted in superior lubrication performance at lower protein concentration (≤10 mg/mL) as compared to WPI. However, at 100 mg/mL, WPI was a better lubricant than PPI, with the former showing the onset of elastohydrodynamic lubrication. Enhanced lubricity upon heat treatment was attributed to the increase in apparent viscosity. Fundamental insights from this study reveal that pea protein at higher concentrations demonstrates inferior lubricity than whey protein and could result in unpleasant mouthfeel, and thus may inform future replacement strategies when designing sustainable food products.

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Paper

Less Corrosive Organomolybdenum Compounds as Lubricant Additives

This invention involves the development of less corrosive, high performing organomolybdenum compounds with applications as additives in lubricants. Lubricants containing …

This invention involves the development of less corrosive, high performing organomolybdenum compounds with applications as additives in lubricants. Lubricants containing these compounds have demonstrated improved performance with respect to friction reduction, wear protection, and copper and lead corrosion, in particular for diesel and passenger car engine oil applications where high performing, more durable additives are required in terms of oxidative and hydrolytic stability.

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Paper

Synergy and Enhanced Performance Retention With Organic and Molybdenum Based Friction Modifier Combination

An improved organic and molybdenum friction modifier combination is disclosed, the combination resulting in a synergistic result of both initial …

An improved organic and molybdenum friction modifier combination is disclosed, the combination resulting in a synergistic result of both initial friction reduction performance and a further retention and durability of continued friction reduction performance. These results will produce added benefit from, e.g., formulated passenger car motor oils targeting lower viscosity formulations to help improve fuel economy.

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Paper

Optimized Production of Fatty Acid Ethyl Esters (FAEE) from Waste Frying Oil by Response Surface Methodology

In Europe, recent regulations on advanced biofuels have prompted a search for new fuel sources and the development of synthesis …

In Europe, recent regulations on advanced biofuels have prompted a search for new fuel sources and the development of synthesis methods meeting the demanding specifications of the sector. However, in developing countries such as Algeria, where a significant stock of frying oil is unused, the use of diesel engines powered with waste-oil-derived biofuels must be explored. In this work, the variables related to the transesterification reaction from this frying oil with ethanol are analyzed using response surface methodology. From this analysis, only the reaction time and temperature have been determined as relevant parameters. In addition, FT-IR analysis has proven a useful tool to analyse the conversion in the transesterification reaction of waste frying oil with ethanol and is cheaper and quicker than GC-FID. This sustainable biofuel (FAEE), mixed with a diesel and pure fuel, has been physically characterized. The mixture of FAEE at 30% by volume with diesel meets the requirements demanded in standard EN 590 and can be classified as winter diesel class D. As a pure biofuel, only its high cold flow temperatures could constitute a drawback for exporting to temperate climates but not for internal consumption.

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