Purpose The purpose of this paper is to study the tribological properties of a thiazole derivatives (T561), overbased alkyl benzene calcium sulfonate (T106A) compounded with T561 and overbased alkyl benzene magnesium sulfonate (T107) compounded with T561 in rapeseed oil (RSO). Design/methodology/approach A four-ball machine was used to evaluate the tribological properties of each compound and their combinations with T561 in RSO. Scanning electron microscopy, EDX and X-ray photoelectron spectroscopy were applied to analyze the tribofilm formed on the worn surfaces. Findings Results of tribotesting demonstrated that synergistic effects exist between the overbased sulfonates, T106A and T107, and the thiazole derivative, T561. The texts of tribofilm indicated that iron sulfide and iron oxides exist in T561 single agent lubricant film and two composite additives lubricant film, and no sulfates were detected. It suggested that the addition of alkyl benzene sulfonate did not hinder the formation of iron sulfides and iron oxides. Meanwhile, CaSO4 (MgSO4) and CaCO3 (MgCO3) were detected on the worn surface of the composite additives, which were not detected on the single agent friction surface. Originality/value A tribofilm mainly contains CaSO4 (MgSO4) and CaCO3 (MgCO3) formed on the worn surfaces, which is responsible for excellent extreme pressure and anti-wear properties of the compound agents because of their high melting point and high shear stress.

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Poly (cyclotriphosphazene-co-4,4 '- diaminodiphenylsulfone) (PZD) microspheres were synthesi zed by precipitation polymerization of Hexachlorocyclotriphosphazene (HCCP) and polyfunctional organic monomers. The products were characterized by FTIR, SEM-EDS, XPS and bet. The adsorption behavior of PZD microspheres for uranium (VI) in aqueous solution and the influence of adsorption behavior were disc ussed. The results show that the PZD microspheres have a certain adsorption capacity for uranium (VI) in a queous solution. When pH = 3.5, adsorption time is 6h, solid-liquid ratio is 2.0g • L-1 and initial concentration of uranium (VI) is 30mg • L-1, the adsorption rate of uranium reaches the maximum.

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