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Copper ion-exchanged X-zeolite with urea infusion was tested for nitrogen oxide (NOx)conversion efficiency in this study. Temperature datapoints were obtained to arrive at peak activation temperatures. Variation of the air/fuel ratio showed the widening of the λ-window(the range of air-fuel ratios over which the NOx conversion efficiency is considerable); a maximum of 62% NOx conversion efficiency was obtained in the lean-burn range. Effects of space velocity variations were also observed. In order to minimise the deactivation of zeolite caused by water, ammonium carbonate and ammonium sulphate were deposited on the copper ion-exchanged X-zeolite and the corresponding NOx conversion efficiencies measured. Ammonia slip (leakage of unreacted ammonia), a prospective pollution hazard, was observed to be more in case of urea infusion than ammonium salt deposition at higher temperatures.

The mechanical and wear behaviour of an alloyed gray cast iron with ausferrite microstructure directly obtained on solidification has been compared with austempered alloyed gray iron. As-cast ausferritic gray iron shows finer ausferrite and graphite flake morphology compared to austempered alloy. The volume of retained austenite is about 30% higher in as-cast ausferritic iron due to higher amount of alloying additions. The mechanical and wear properties of as-cast ausferritic iron are almost similar to austempered alloy.

Copper is almost inevitable functional filler in the brake-material and efforts to replace it are continuing since it is now known as a hazard to the aquatic life. It is always desirable to search for ingredients for Cu-free brake-pads, which will be beneficial for friction-related properties and especially fade resistance. Attapulgite, is a mineral which was proven to be an excellent substitute for asbestos in brake-pads long back. However, hardly anything in details is reported on its exact role in controlling tribo-properties of friction materials (FMs). It was of interest, if it can be helpful in enhancing the performance of Cu-free FMs. Hence, in this work a series of brake-pads (five types) was formulated and developed with increasing amount of attapulgite (0, 5, 10 and 15 wt. %) by compensating with inert barite particles in Cu-free FMs. The parent composition was fixed and instead of Cu powder, 10 wt.% stainless steel powder was used.

Three catalysts based on X-zeolite have been developed by exchanging its Na+ ion with Copper, Nickel and Vanadium metal ions and tested in a stationary SI engine exhaust to observe their potentialities for NOx and CO controlling. The catalyst Cu-X, in comparison to Ni-X and V-X, exhibits much better NOx and CO reduction performance at any temperature. Maximum NOx conversion efficiencies achieved with Cu-X, Ni-X and V-X are 62.2%, 59.7% and 56.1% respectively. Unlike noble metals, the doped X-zeolite catalysts, studied here, maintain their peak NOx reduction performance through a wider range of A/F ratio. Back pressure developed across the catalyst bed is found to be well within the acceptable limits.

Graphite plays a crucial role in friction materials, since it has good thermal conductivity, lubricity and act as a friction modifier. The right type, amount, shape, and size of the particles control the performance of the brake-pads. The theme of the study was investigating the influence of size of graphite particles (having all other specifications identical) on performance properties of brake-pads containing graphite particles in the average size of 60 μm, 120 μm, 200 μm and 400 μm. Physical, mechanical and chemical characterization of the developed brake-pads was done. The tribological performance was studied using a full- scale inertia brake dynamometer following a Japanese automobile testing standard (JASO C406). Tribo-performance in terms of fade resistance, friction stability and wear resistance were observed best for smaller graphite particles. It was concluded that smaller size serves best for achieving best performance properties barring compressibility.

There is a growing need for improved conceptual vehicle designs along with alternative materials to reduce the damage to the passengers and structures in aerospace and automotive industries. The energy absorption characteristics of materials play a major role in designing a safe vehicle for transport. In this paper, compression behavior and energy absorption of aluminum alloy AA6061 and AA7005 tubes in T4 and T6 conditions are investigated by experimental and numerical methods. The AA7005 and AA6061 tubes are solution heat treated and then aged to achieve the final strength in T6 condition. Experimental compression test results have shown improved energy absorption of tubes in T6 condition compared to tubes in T4 condition. There is less variation of energy among the tested samples. The mean load is compared with the results obtained from analytical formulae. Tensile properties have been obtained from tensile tests using UTM for both AA6061 and AA7005 tubes.

Road accidents and persons killed in India have been reported to the tune of 4,90,383 and 1,38,258 respectively during 2012. On National Highways (NHs), major share of accidents (about 29%) and number of persons killed (35.3%) are observed out of total accidents. National Highways in India constitute about 2% of total road network (92,851 km) in India, but carries about 40% of traffic. 46% (42,829 km) of NHs in India comprises of two-lane and about 19% (17239 km) of NHs are single or intermediate-lane. Road accidents being multi-disciplinary in nature involves attention of multiple departments such as Highways Authority, Police, Motor Vehicles, Automobile Manufacturers, NGOs, etc. Owing to spurt in growth of motor vehicle population in India, road accidents are not reduced significantly despite improvement in NHs (widening of carriageway and riding quality).