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The purpose of this paper is to investigate if there is any impact of reporting delays on profitability of front-running strategies against the mutual funds.

The author studies if freshness of mutual fund holding information from public disclosures affects precision of flow-based front-running strategies against the funds and if the allowed 60-day reporting delay is able to protect the funds from these front-running activities against them.

Assuming no reporting delay, the author finds that returns from hypothetical front-running strategies are significant, when these are based on the most recent holding information and are not significant, when based on relatively old holding information. Interestingly, these front-running returns appear to be mostly driven by anticipated forced buys by the mutual funds (rather than anticipated forced sales). The return from a front-running strategy long on anticipated forced buys is higher when it is based on relatively illiquid assets. The author also finds that return from a front-running strategy short on anticipated forced sales is significant, when it is based on illiquid assets from relatively old holding information.

Hence, it appears that the allowed 60-day reporting delay is able to protect most of the funds from front-running activities against them, except for the funds holding illiquid assets from anticipated forced sales motivated front-running activities against them.

The paper addresses an interesting question, which has not been studied before – if freshness of fund holding information helps the front-running strategies against the funds and if the allowed reporting delay is effective in protecting the funds from these activities.

The purpose of this paper is to study the dispersion and tribological properties of liquid paraffin with aluminum nanoparticles as additive, which are prepared by the surface‐modification method using oleic acid (OA).

The dispersion stability of aluminum nanoparticles in liquid paraffin is measured by spectrophotometry, which can be optimization by Taguchi method. The tribological properties are evaluated by using a ball‐on‐ring wear tester.

The results show that few concentrations of aluminum nanoparticles as additives in liquid paraffin have better antiwear and antifriction properties than the pure paraffin oil. Scanning electron microscopy and energy dispersive spectrometer analyses can show that the thin films on the rubbing surfaces can be formed by these aluminum nanoparticles, which not only bear the load but also separate the both interfaces, thus the wear and friction can be reduced.

Machine components and mechanism pairs rely on high‐quality lubricants to withstand high temperature and extreme pressure. Extreme pressure and antiwear additives are typically adopted to improve the tribological performance of a fluid lubricant in reducing friction and surface damage under severe conditions.

The combined use of anticorrosive and load carrying additives in industrial and automotive lubricants has been well known for many years. In some cases, the same additive has been claimed to act both for load carrying and anticorrosive properties. The synergistic and antagonistic effects of various chemicals involved in lubricant system employing both these two types of additives are the subjects of present interest.

EXTREME PRESSURE OR EXTREME TEMPERATURE LUBRICANTS have been developed for two main fields—the lubrication of hypoid gears and as lubricants in metal working and it is of some interest to see how this development has occurred. Musgrave, in a most comprehensive paper on the Development and Lubrication of the Automotive Hypoid Gearf defined a hypoid as “a special form of spiral bevel gear in which the pinion axis is offset from the axis of the ring gear” and he pointed out that such gears had the advantages of quietness in operation, particularly at high speeds, greater tooth strength capacity, greater dependability and were more economic to produce as well as allowing lower body designs than spiral bevel or worm gears.

Formulation of mineral-based specialty lubricants without anti-wear (AW) and extreme-pressure (EP) additives is a challenging task. This study aims to propose an environment friendly alternative to mineral-based lubricants with superior wear preventive characteristics.

In this study, analysis of wear under trimethylolpropane trioleate (TMPTO)-based lube using operating parameters of four-ball tester was done. The effects of type of lube oil, temperature, load and speed on specific wear rate were investigated using Taguchi L27 orthogonal array. Based on the Taguchi experimental results and single-to-noise ratios, ranking of the four ball parameters was done. The surface analysis of worn steel balls was carried out using optical microscopic images of wear scar and energy dispersive spectrometry (EDS).

Results depict that the blend of sulfurized additives with TMPTO base oil showed a synergistic effect in terms of reduction in specific wear rate by the formation of protective film layer on the surface. The possible physical or chemical interactions between base oil and additives were studied based on the surface morphology of test balls.

The formulated lubricant has the potential to be used as a tapping/broaching oil.

To the best of the authors’ knowledge, the paper is a novel study investigating the effect of different additive in TMPTO. The results could prove beneficial in making TMPTO-based lube oil a viable replacement of mineral-based oils.

LONG before man learnt to make fire by the friction of wood, he experienced the burden of friction in dragging home his kill. Perhaps it is not too fanciful to suppose that the torn sides of his beast gave the first solid lubricant. Blood and mutton fat were seriously recommended as lubricants for church bell trunnions as recently as the 17th century. Indoed we still reckon fatty acids the best of all boundary lubricants. The range of man's activities has increased enormously in the present century, and particularly in the last few decades. Men have circled the earth in space; a space ship is on its way to examine another planet; terrestrial man is boring to the bottom of the earth's crust; others have descended to the depths of the ocean, and oven established a home on the floor of the Mediterranean, Speeds have increased by factors of thousands, temperatures range from near absolute zero to thousands of degrees; and a new environment of high‐intensity nuclear radiation has been created. Still, objects must move over and along each other in these exotic conditions; and to a large extent solid lubricants can provide the answer to the frictional problems.

The physical and chemical properties of a new class of synthetic lubricants, the perfluoroalkylpolyether oils and the polytetrufluoroethylene‐thickened greases made from these oils, are described in some detail. The properties which make these products of interest as lubricants for use under severe conditions are shown to be I) excellent thermal and oxidative stability, 2) extreme inertness to many reactive chemicals, 3) broad liquid range and good viscosity‐temperature characteristics, 4) complete nonflammability, 5) good lubricating qualities, 6) compatibility with most elastomers and metals at suitable operating temperatures and 7) insolubility in most common solvents. The commercial process used in the production of these lubricants is described. The oils are disclosed to be fluorine end capped polymers of hexafluoropropylene epoxide having number average molecular weights of from 2000 to 7500, and the preferred thickener for the greases is disclosed to be a telomer of tetrafluoroethylene having a molecular weight of 20,000 to 30,000. A number of the commercial uses of these oils and greases, sold by Du Pont under the trade‐name Krytox®, are described including specific examples of instances where their performance far exceeded that of other available lubricants. Some uses in the space and aircraft industries are also discussed.

This study aims to investigate the noise-inducing characteristics during the start-up process of a mixed-flow pump and the impact of different start-up schemes on pump noise.

This study conducted numerical simulations on the mixed-flow pump under different start-up schemes and investigated the flow characteristics and noise distribution under these schemes.

The results reveal that the dipole noise is mainly caused by pressure fluctuations, while the quadrupole noise is mainly generated by the generation, development and breakdown of vortices. Additionally, the noise evolution characteristics during the start-up process of the mixed-flow pump can be divided into the initial stage, stable growth stage, impulse stage and stable operation stage.

The findings of this study can provide a theoretical basis for the selection of start-up schemes for mixed-flow pumps, reducing flow noise and improving the operational stability of mixed-flow pumps.

This series of articles continues the theme of Mr. Brewer's preveious series, “Lubrication—Management Responsibility” The series deals with the lubrication of industrial plant, but with the intention of ‘educating’ Management to the importance of ensuring that production is not lost because of faulty lubrication.