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IN RECENT YEARS engineers concerned with the design and development of oil‐hydraulic equipment have shown an increasing thirst for information on hydraulic oils, and particularly for quantitative data on their physical properties. The following notes review the requirement for data, and the significance of the properties of closest concern to the designer.

To develop a potential substitute for conventional lubricant additive and improve the oil-solubility of nanoparticles, calcium borate nanoparticles modified by an eco-friendly or “green” modifier lauric acid (CBLA) were prepared. The paper aims to discuss these issues.

The microstructures of the as-obtained samples were characterized by X-ray power diffraction (XRD) transmission electron microscope (TEM) and infrared spectra (IR). The contact angle was also measured. Tribological properties of CBLA used as additive in base oil were evaluated with a four-ball tribotester and compared with a commercial additive. The worn surface was investigated by polarized microscope (PM) and X-ray photoelectron spectroscopy (XPS).

The results indicate that the average size is in the range of 50-100 nm and the surface of calcium borate was altered from hydrophilicity to hydrophobicity. At the same time, the nanoparticles can be dispersed well in the base oil. Tribological results show that CBLA have good antiwear property and friction-reducing property in base oil, and it can be found that during the sliding process, a continuous wear resistance film was formed which containing depositions and the tribochemical reaction products such as B₂O₃, FeB, Fe₂O₃ and CaO.

An eco-friendly or “green” modifier lauric acid could change the surface of calcium borate from hydrophilicity to hydrophobicity, and calcium borate modified by lauric acid has good tribological properties in lubricating oil.

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.

The purpose of this paper is to test two kinds of rare earth complexes of Lanthanum Dialkyldithiophosphate (LaDDP) and Lanthanum Dialkylphosphate (LaDP) as lubricant additives in liquid paraffin for the untreated 60Si2Mn steel and laser‐cladding Ni35A coating on 60Si2Mn steel sliding pairs which are a potential substitute for Zinc Dialkldithiophosphate (ZnDDP).

Tribological properties were evaluated by an Optimol‐SRV oscillating friction and wear test. The morphologies of the worn surfaces were observed by a scanning electron microscope (SEM), and the chemical states of several typical elements on the worn surfaces were examined by means of X‐ray photoelectron spectroscopy (XPS).

Treated laser cladding coatings of steel can improve its hardness and strength and the coated steel possess higher load‐carrying capacity than that of 60Si2Mn; The rare earth complexes of LaDDP and LaDP possess good oil‐solubility, friction‐reducing and wear resistance properties. Those rare earth complexes as additives in liquid paraffin during the friction process can form a protective film containing rare earth oxide, sulfate and sulfur‐containing compound during the friction process.

The paper presents two kinds of potentially useful, environmentally‐friendly and highly efficient substitutes for the ZnDDP additives in lubricants.

Owing to their good friction‐reducing and wear resistance properties, LaDDP and LaDP are two optimum and promising industry lubrication additives.

This work is a new application of rare earth complex as lubricant additive in liquid paraffin, which provides a new direction for designing friction pairs and lubricant additive. The tribology experiments have been carried out through the variation of experiment conditions.

Combination of ASTM D 855‐56 and cationic titration methods to evolve a very rapid and precise method for the analysis of petroleum sulfonates with respect to molecular weight and sulfonate content. Active ingredient as R·SO3Na where R is a naphthenic aromatic nucleus having one side chain).

The purpose of this paper is to synthesise the tercopolymer PMMA‐co‐PHFBA‐co‐PHPA in an ab initio emulsion through activators regenerated by electron transfer for atom transfer radical polymerisation in the absence of F‐containing surfactant and organic assistants.

To produce the tercopolymer of methyl methacrylate, hexafluorobutyl acrylate, and 2‐hydrothyl propyl acrylate with a precise macromolecular composition and structure, water used as the dispersion medium, Tween‐80 and SDS as emulsifiers, soluble ascorbic acid as the reducing agent and benzyl bromide as the initiator. The catalyst was CuBr₂/O‐phenanthroline complex. The molecular structure of the polymer was characterised by FT‐IR, Raman, and ¹H‐NMR. Molecular weight and molecular weight distributions were measured by gel permeation chromatography.

The polymer molecular composition and structure are controllable during polymerisation as defined without nitrogen protection. However, the average molecular weight of the polymer deviates from the theoretical value when the monomer fractional conversion reaches 90 percent. The molecular weight distribution of the polymer (PDI=1.4) is much broader than those done in bulk or solution polymerisation.

Integrating ab initio emulsion with activators regenerated by electron transfer via atom transfer radical polymerisation (ARGET‐ATRP) technologies could be a significant method for producing functional acrylic‐fluoropolymer with defined macromolecular composition and structure, even in the absence of F‐containing surfactant and organic assistants, both of which are necessary in the normal case.

This study aims to probe the applicability of 2-mercaptobenzothiazole (MBT) functionalized ionic liquids (ILs) as additives in lithium complex grease (LCG) by researching the corrosion inhibiting, rheological and tribological performances.

Electrochemical tests such as electrochemical impedance spectroscopy and potentiodynamic polarization curves were used on Gamry electrochemical workstation to research the corrosion inhibition properties of ILs in 1.0 M HCl corrosive solution. The rheological properties of different grease samples were tested on a rheometer. The tribological properties were investigated on SRV-V oscillating reciprocating friction and wear tester. Scanning electron microscope, X-ray spectrometer and X-ray photoelectron spectrometer were used to characterize the lubricating mechanism.

The 2-MBT functionalized ILs have excellent corrosion inhibition properties. When used as additives in LCG, they both exhibited enhancing effects on thermostability, colloid stability and structural recoverability, and furthermore, outstanding friction-reducing and antiwear properties were also obtained. Surface analysis indicated that the superior lubricating performances of 2-MBT functionalized ILs were mainly ascribed to the formation of tribochemical products on wear tracks, including organic compounds with C–O bond, Fe₂O₃ and FeS₂.

The 2-MBT-based ILs synthesized in this study were multifunctional additives with excellent corrosion inhibiting and tribological properties, which would have a very broad application prospect in lubricating grease industry.

The purpose of this paper was to develop an antimicrobial edible film coated with essential oils for packaging application with characterization of its physicochemical properties. Livestock products especially meat products need special packaging system for protection. The most well-known packaging materials are polyethylene or co-polymer-based materials which have led to serious ecological problems due to their non-biodegradability and non-renewable nature. There has been a growing interest for edible films in recent years trying to reduce the amount of wastes, capable of protecting the food once the primary packaging is open, and because of public concerns about environmental protection. Various kinds of antimicrobial substances can also be incorporated into edible films to improve their functionality, as these substances could limit or prevent microbial growth on food surface.

Biopolymers such as carrageenan and carboxymethylcellulose and their various combinations were tried to develop an edible film. The levels of antimicrobial substances such as oregano and thyme essential oils were standardized on the basis of their minimal inhibitory concentration against Escherichia coli, Salmonella pullorum, Staphylococcus aureus and Listeria monocytogenes. Standardized edible film coated with standardized concentration of essential oil was examined for different physicochemical properties and compared with edible film without essential oil.

In total, 1.5 per cent (w/v) solution of carrageenan was found best suited biopolymer for edible film formation on the basis of thickness, transparency and elongation ability. Combined concentration of oregano (0.02 per cent) and thyme (0.03 per cent) essential oils were found to be best suited for coating the edible film as antimicrobial application.

Future research may benefit from the present attempt in evaluating the potency of easily available agricultural by produces for preparation of economically viable edible film incorporated with various natural biopreservatives in combination for the enhancement of shelf life.

Antimicrobial packaging for enhancing the quality and shelf life of stored meat products offers great scope for further research in this field. Moreover, the literature pertaining to the application of edible films containing biopreservative for chicken meat products is very limited.

Nanoparticles are not well dispersed in non‐polar organic solvents due to their hydrophilic property which limits their applications in lubricant oils. To improve the oil‐solubility of nanoparticles, a novel technology was used to prepare a kind of lubricant containing calcium borate nanoparticles.

The microstructures of the prepared nanoparticles were characterized by transmission electron microscope (TEM) and infrared spectra (IR). Tribological properties of calcium borate nanoparticles used as additive in base oil were evaluated using four‐ball tribotester and SRV tribotester, and the worn surface of the steel ball was investigated by Polarized microscope (PM) and X‐ray photoelectron spectroscopy (XPS). In addition, the dispersing stability and antioxidation property of lubricant containing nanoparticles were also studied.

The results indicate that the average size of the prepared nanoparticles is in the range of 50‐100 nm, and the surface of the nanoparticles was altered from hydrophilicity to hydrophobicity. At the same time, the nanoparticles can be well dispersed in the base oil totally under novel process which has no significantly negative effect on the antioxidation property. The results of tribological tests show that calcium borate nanoparticles under the novel process (CBNN) show better antiwear property and friction‐reducing property in base oil compared to calcium borate nanoparticles under tradition process (CBNT). Based on the results of PM and XPS, it can be deduced that a continuous resistance film containing depositions and the tribochemical reaction products such as B₂O₃, FeB, Fe₂O₃ and CaO formed during the sliding process.

The main innovative thought of this work lies in dealing with the oil‐solubility problem through the combination effect of surface modification and special blend process of lubricating oil, and this method was first used to prepare lubricant containing calcium borate nanoparticles. It should be helpful for the borate nanoparticles used as additives in engine oil, gear oil and other industrial lubricants.

Thiadiazole compounds and their derivatives have carrying capacity and good lubricating properties. However, their poor oil-solubility limited their wide usage in lubricating oil. The study aims to develop thiadiazole lubricant additives with better oil-solubility. When the hindered phenol antioxidation functional group and alkyl-chain are introduced to thiadiazole, the resulting product could have better oil-solubility and excellent antioxidation resistance, anti-wear and corrosion resistance in the lubricating oil.

One kind of thiadiazole lubricant additive, for the first time, has been synthesized from 2,5-dimercapto-1,3,4-thiadiazole. Its tribological performance has also been evaluated by four-ball test. And, its oxidation resistance has been estimated by rotating pressure vessel oxidation test and pressurized differential scanning calorimetry. The anticorrosion performance of such an additive has been studied by GB/T 5096 standard method test.

The synthesized thiadiazole additive has excellent anti-oxidation capability, good anti-wear and extreme pressure properties and good anticorrosion performance, in comparison with zinc dialkyl dithiophosphate (ZDDP). In base oils, the comprehensive performance of thiadiazole additive is comparable to ZDDP. Mechanistic studies indicate that the S and N active elements were involved in the formation of a boundary film. This may account for the formation of a composite membrane on the metal surface and thus for the tribological performance of such thiadiazole additives.

The thiadiazole derivatives, which are ashless and have environmentally friendly features, are a potential alternative to ZDDP. Because of the film formed on the friction surface, thiadiazole compounds may serve as an excellent anti-wear additive and are expected to reduce friction and wear between metals.