The development of the freezing and export of prawns in India

The paper deals with an overview on the preservation of fish by freezing process. Until a few years ago the surplus catches of fish, prawns were being dried, salted or pickled. The Kerala coast had always yielded large catches of prawns and about 5000 tons of dried prawns were annually exported to Burma and other Eastern countries. The Government of India looking at the great potential of this industry, has now, with a view to encourage exports, provided a series of incentives towards this end.

Abrasive wear of steel during rolling-sliding contact with rock counterfaces

In many mining operations (e.g. excavation, drilling, tunnelling, rock crushing) metallic components are forced against abrasive rocks in a complex motion. This study examines the relative importance of combined rolling and sliding motion in the two-body abrasive wear of a low carbon tempered martensitic steel against rock counterfaces. A novel wear test rig has been used to vary the amount of rolling and sliding motion between a rotating steel cylinder and a counter-rotating sandstone (highly abrasive) or limestone (much less abrasive) disc. Weight-loss measurements reveal that the wear rate of the steel increases as the amount of motion against the rock counterface is reduced from pure sliding to approximately 50% sliding (and approximately 50% rolling). Scanning electron microscopy shows that when the amount of motion is reduced from pure sliding to approximately 50% sliding the topographical and sub-surface physical properties of the worn steel and rock surfaces are modified.

Socio-economic implications of the fish export trade in Uganda

Implications of the fish export trade on the people and the fisheries resource of Lake Victoria, Uganda were examined. Eight fish processing factories and ninety fishers were analyzed in terms of socio-economic characteristics of fishers and the economic characteristics of fish factories. Results indicated that industrial fish processors in Uganda are presently the main link between the artisanal fisher-folk and the overseas export markets. Their entry into the market has stabilized and expanded the fisher-folk market and average earnings. Fishers attributed improvement in incomes and living standards (76%) to positive changes in the fish market (78%) in the last 5 years (1994-1999). Ugandan fisher-folk communities are not seriously affected by the Nile perch exports (73%) because they normally have easy access to cheap fish at prices much less than urban prices and; depend mainly on alternative fish species of less export value. The price of Nile perch influences positively the price of Tilapia

Friction and material transfer in micro-scale sliding contact between aluminium alloy and steel

A ball-on-flat reciprocating micro-tribometer has been used to measure the friction coefficient between aluminium alloy strip and a steel ball. A relatively small ball and correspondingly low contact load is used to give a contact width of the order of 100μm, closer to asperity contact widths than generally found for this type of test. The effects of load, initial strip surface roughness, lubricants and boundary additives are investigated. It is found that the friction coefficient is significantly reduced by the addition of a lubricant. Observations of the wear tracks and ball surface show that the material transfer from aluminium to the ball is reduced in the presence of the lubricant. The initial friction coefficient is further reduced by the addition of a boundary additive, but the friction coefficient after 8 cycles is unchanged. Copyright © 2004 by Springer Science+Business Media, Inc.