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Because of the continuing usage of nitrocellulose lacquers, a study of the thinners to determine the percentages of the components is very important. Usually these thinners consist of a mixture aromatic and alphatic hydrocarbons (as diluents or non solvents) and ketones, esters and ethers (as solvents).

There is an increasing interest in textured finishes both from the manufacturer's and the user's point of view. The paint formulator is increasingly being asked to produce paints and coatings to provide these textures and this article aims to provide some suitable formulations for the technologist to use as a basis for his work.

The decrease in availability of mineral oils and their environmental hazards created the need to search for alternate bio-based oils. The aim of this study is to investigate the friction and wear characteristics of kapok (Ceiba pentandra) oil as a bio-lubricant.

The wear and friction characteristics between steel-steel contact under lubrication were found using a pin-on-disk tribometer under different loads and sliding speeds, respectively. The corrosion and oxidation stability of the test lubricants were also analyzed. The worn surfaces of the specimen are analyzed with the help of an optical microscope. The obtained results were compared with palm oil and mineral oil (SAE20W 40).

From the investigation, it is found that the kapok oil possess a lower coefficient of friction and wear rate than palm and mineral oil. It is also found that the coefficient of friction varies proportionally and the wear rate varies inversely with the sliding speed as expected.

The present results confirm that the kapok oil can be used as an alternative lubricant to reduce the demand for mineral-based oil lubricants.

This paper aims to analyse the differential impact of foreign and domestic remittances on household expenditure shares.

This study uses micro-data from a very large and detailed income-expenditure survey in Mexico and runs consumption-share Engel equations to estimate income (expenditure) elasticities for different consumption goods groups. Trying to account for the standard problems of endogeneity, this paper considers only nuclear households with migrant fathers and compare households that receive remittances from abroad, from within Mexico and those not receiving remittances.

This study finds that international remittances have a larger impact on the expenditure shares of women’s clothes, insurances and durable goods, while domestic remittances have a larger impact on the share of income dedicated to food, health and education.

Based on the results, differences in consumption shares between families receiving foreign and domestic remittances might depend not only on the relative size of the income transfer but also on the nature of the transfer and the sender’s capacity to monitor in person the use of those remittances. The results indicate that households that receive remittances from abroad present higher shares of consumption of some goods the literature commonly associates with the mothers’ preferences.

The purpose of this paper is to synthesize a microemulsion and investigate its tribological properties as lubricant. Magnesium alloy warm rolling experiments were conducted. Surface morphology was observed and wear form was summarized. The composition of surface residues was analyzed, which sheds light on the lubrication mechanism of microemulsion.

A microemulsion was prepared with a proper amount of oil, surfactant, cosurfactant, water and other additives for magnesium alloy strip warm rolling. Tribological properties, such as maximum non-seizure load (P_B), friction coefficient (μ) and wear scar diameter (D) of the microemulsion were measured and compared with those of emulsion and rolling oil on an MR-10A four-ball tribotester. The extreme pressure anti-wear coefficients (O) were calculated and compared. Warm rolling experiments were carried out on a Ф 170/400 × 300 mm four-high rolling mill at 240°C to compare the finish rolling thickness and surface quality of rolled AZ31B magnesium alloy strip under four lubrication states, namely, no lubrication, rolling oil, microemulsion and emulsion. The surface morphology after warm rolling was observed with confocal laser scanning microscope and scanning electron microscope, respectively. The composition of surface residues was analyzed with energy dispersive spectrometry and X-Ray photoelectron spectroscopy.

Surface morphology indicated that pitting wear, adhesive wear and ploughing wear were three main forms of wear in magnesium alloy warm rolling. Microemulsion had excellent lubrication properties with less residual oil remaining. Two types of adsorption layers formed on magnesium alloy strip surface were responsible for lubrication properties. MgSO₄ and magnesium stearate in the reaction layer played a key role in anti-wear and friction-reduction in warm rolling.

The study is original and gives valuable information on lubrication mechanism of microemulsion in warm rolling of magnesium alloy strips.

This paper aims to contrastively investigate the antioxidant behavior and tribological performance of a novel multifunctional additive (PBT) and dialkyldithiophosphate (ZDDP) in complex lithium grease (CLG).

PBT was successfully synthesized through esterification reaction. The antioxidant behavior of PBT and ZDDP was investigated by thermal analysis, and meanwhile, their tribological performance was evaluated by Optimol SRV-IV oscillating reciprocating friction and wear tester (SRV-IV test) and MRS-1J four-ball tester (Four-ball test). Furthermore, their anticorrosion ability was determined by copper strip corrosion test.

Four-ball tests showed that the extreme pressure property of PBT was a little inferior to that of ZDDP. Besides, all the other results demonstrated that PBT showed more superior antioxidation stability, friction-reduction and antiwear ability, as well as anticorrosion performance than ZDDP.

This work provides a study of hindered phenol derivative as a multifunctional additive in lubricant grease, which can contribute to the development of substitution of ZDDP.

PARTS 12–15 IN A SERIES OF THIRTY‐ONE SHORT ARTICLES DESIGNED TO EMPHASIZE TO MANAGEMENT EXECUTIVES THE SAVINGS THEY CAN EFFECT AND FOR WHICH THEY ARE RESPONSIBLE BY GIVING THOUGHT AND ATTENTION TO THE CORRECT LUBRICATION OF THEIR PLANT AND MACHINERY.

The latest cutting oil additives produced by Hornett Bros. & Co. Ltd., Gooseley Lane, Barking By‐Pass, Barking, Essex, and known as Epoil Controlled Release Additives, claim to overcome the disadvantage of low temperature corrosivity when using ‘active’ oils.

The purpose of this paper is to synthesize a kind of core-shell Ag@polyaniline (Ag@PAN) as a lubricant additive to improve the friction reduction and anti-wear abilities of lithium-based complex grease.

The core-shell Ag@PAN was prepared by a simple method and was introduced into the lithium-based complex grease. The typical properties of Ag@PAN were investigated by scanning electron microscopy (SEM), Fourier transforms infrared spectrometer and thermal gravimetric analyzer. The tribological properties were evaluated under different conditions. After the tribological test, the worn surface was analyzed by SEM and X-ray photoelectron spectroscopy to probe the lubrication mechanisms.

The prepared Ag@PAN could greatly improve the friction reduction and wear resistance of the friction pair under different conditions. The preferable tribological performances were mainly attributed to the synergism of various lubrication mechanisms including “mending effect,” “rolling effect” and lubricating protective film, and so on.

This study synthesizes a new kind of core-shell Ag@PAN as a lubricant additive, and it possesses preferable friction reduction and anti-wear abilities.

Sulfurized olefins have been extensively used in many kinds of gear lubricants as EP additives. However, their commercial applications are not totally satisfactory because of the pungent, obnoxious odor and corrosion of copper and copper alloys. The purpose of this paper is to investigate the synergistic effects of one type of calcium borate nanoparticles modified by oleic acid (code to CaBN) and sulfurized olefin, in a kind of mineral base oil MVIS 250, in order to find a potential substitute for sulfurized olefins.

One kind of calcium borate nanoparticle modified by oleic acid (CaBN) was prepared, and its structures were characterized by inductively coupled plasma atomic emission spectroscopy (ICP‐AES), X‐ray power diffraction (XRD) and transmission electron microscope (TEM). The tribological properties of the complex of CaBN with sulfurized olefins (T321) in base oil were evaluated using four‐ball tribotester and compared with CaBN or T321 as individual component. The worn surfaces were investigated by scanning electron microscope (SEM) and X‐ray photoelectron spectroscopy (XPS). In addition, the corrosion‐inhibiting properties of additives were also studied.

The results of tests show that there are significant synergistic effects on tribological properties between two kinds of additives. Based on the results of SEM and XPS, it can be deduced that a wear resistance film containing B₂O₃, FeS, FeS₂ and CaO was formed on the worn surfaces during the sliding process. Moreover, CaBN and T321 also show excellent synergistic effect on the corrosion‐inhibiting property.

This paper provides a kind of “green” nanoparticle which possesses excellent synergic effect with sulfurized olefins, and gives another selection for industrial applications in which T321 is needed.