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The purpose of this paper is to identify the feature of soot in diesel engine oil and provide a method to stably disperse these soots using effect additives which is benefical for lubricants to pass related engine tests.

This paper designed experiments to investigate the dispersant type, treat level and different dispersant interactions which influence on lubricant soot-related viscosity increase. The research work developed an effective dispersant package which can well solve the soot-related viscosity increase, allowing pass Mack T-11 and Mack T-8 engine tests and demonstrated the helpfulness of using a quickly screening method developed by a steel piston diesel engine CA 6DL2-35.

The effect of dispersant treat level on the viscosity increase of the oil samples was negligible. Dispersant booster can effectively improve the soot handling ability of heavy-duty diesel engine oils (HDDEO), and the appropriate treat level of dispersant booster can help HDDEO pass Mack T-8 and Mack T-11 engine tests.

The test results are useful for formulators to select the appropriate dispersants or dispersant booster to develop the HDDEO packages which can meet the modern diesel engine lubrication requirements.

Most previous studies in this field were carried out on soot formation mechanism and soot-related wear rather than how to solve the soot-related viscosity increasing of HDDEO. This paper describes the soot dispersing requirements of different HDDEO specifications and developed an effective dispersant package which can well deal with Mack T-11 and Mack T-8E standard engine tests soot handling ability requirements.

Crankcase lubricants for automotive and commercial use are differentiated by their physico‐chemical properties but more importantly by their performance in a series of engine test sequences. The sequences are devised by committees formed by representatives from the vehicle manufacturers, the oil companies and the additive suppliers. The article describes the sequences devised by the American Petroleum Institute and the European ACEA organisations, including some historical background as well as the current specifications. Methods of compliance monitoring and enforcement are also covered.

The purpose of this paper was to improve the frictional wear resistance properties of piston skirts caused by the low viscosity lubricant by studying the tribological performance of three novel coating materials.

Comparative tribological examinations were performed in a tribological tester using the ring-block arrangement under two viscosity lubricants, the loading force was applied as 100 N, the speed was set to 60 r/min and the testing time was 180 min.

Under low viscosity lubricant, the friction coefficient and wear of the three coatings all increase, and the friction coefficient and wear of the PTFE coating are the largest, while the MoS₂ coating has the lowest friction coefficient and wear. Under low viscosity lubricant, the friction coefficient of the MoS₂ coating is 2.1%–5.4% and 20.0%–24.3% lower than that of the SiO2 and PTFE coating, respectively. The friction coefficient and wear fluctuation rate of the MoS₂ coating is the smallest when the lubricant viscosity decreases, which indicates that the MoS₂ coating has excellent stability and adaptability under low viscosity lubricant.

To reduce the piston skirt wear caused by low viscosity lubricant in heavy-duty diesel engines, the friction and wear adaptability of three novel composite coating materials for piston skirts were compared under 0 W-20 low viscosity lubricant, which could provide a guidance for the application of wear-resistant materials for heavy-duty diesel engine piston skirt.

Increasingly stringent European market requirements for improved heavy duty diesel engine performance, such as fuel economy and durability, continue to highlight the need for higher performance engine lubricants. To meet this need, new additive technology is being used in combination with higher quality base‐stocks and has resulted in a growing trend towards the use of oils of lower viscosities than those used in the past. Such a trend has led to some concern over the ability of low viscous oils to maintain adequate engine wear protection, not only during extended service operations but also under the more severe conditions of low temperature engine start‐up. This paper describes the results of a recent study to evaluate the effect of base oil composition and viscosity grade on the low temperature performance of a modern Euro II diesel engine with respect to wear, using the technique of Thin Layer Activation. Engine test results showed that the use of full synthetic SAE 5W40 grade oils based on Polyalphaolefin provided enhanced low temperature cylinder liner wear protection.

This paper analyzes two external costs often associated with port development, cost to fisheries from marine dredge disposal and damages from air pollution, using estimates of development and operation for a proposed (but since cancelled) container port as a case study. For dredge disposal, a bio-economic model was used to assess short- and long-term and indirect (joodweb) damages to fisheries from marine disposal of clean sediments. In the case of air pollution, estimates of annual activity levels and emission coefficients are used to estimate incremental annual emissions of three key pollutants (NOx, HC and CO) for trucks, trains, yard vehicles, and vessels. These estimates allow for phasing in of strict new air pollution regulations. For both external costs, sensitivity analyses are used to reflect uncertainty. Estimates of shadow values in year 2002 dollars amount from $0.094 per cubic yard to $0.169 per cubic yard of clean dredged material for the selected disposal site and from $0.0584 per mile (jor current control standards) to $ 0. 0023 per mile (after phasing in of new regulations) for air pollution from heavy trucks.

The objective of this paper is to evaluate the potential sustainable transportation strategies for Cairo in terms of their impact on emissions over the next ten years. The considered strategies include using cleaner fuel, implementing inspection and maintenance programs and adopting emission standards for new vehicles.

The strategies were evaluated in terms of the expected reductions of particulate matter (PM) and ozone precursors due to the future implementation. Emissions were estimated utilizing a mix of the relevant national and international. Accordingly, a three‐phase integrated strategy is recommended, considering the local technical and institutional aspects.

In case of no actions taken, emissions of PM and ozone precursors could increase at the year 2013 by 95 and 50 percent, respectively. Implementing the proposed integrated strategy could result in reducing the emissions of PM and ozone precursors by about 53 and 49 percent, respectively.

The proposed strategy is applicable because the targets are set considering the local aspects. However, the estimated emission reductions could almost compensate for the increase in the fleet size over the time. Therefore, achieving real reductions of emissions requires additional strategies to be considered.

Owing to the lack of local emission factors and measurements, this original work highlights the expected impacts of the potential strategies for controlling vehicle emissions in Cairo. Also, the findings indicate the need to consider other additional strategies in the long term planning process.