1996 Student Winners

Categories:

Biology and Microbiology

Mark Newman
Year 12, St Stanislaus' College, Mudgee, NSW

'Recycling Sewage Sludge'

Mark's local community of Mudgee, New South Wales, had attempted to solve its problem with the disposal of waste paper and sewage sludge by composting the sewage with shredded newspaper.

After learning of community comments questioning the value of the compost, Mark decided to begin his investigation. Mark investigated the viability of recycling sewage sludge by researching its effectiveness as a compost growth medium for crops.

By testing three types of sewage composts and two commercial control composts, Mark experimented with Radish crops.

Mark discovered that sewage sludge composts provide a good soil medium which is competitive with commercial composts. He found that compost may improve the productivity of top soil and could be developed for a variety of potential uses such as a potting mix or soil conditioner.

In general, Mark found that the sewage sludge compost has great potential for use in agriculture. His excellent research indicates that sewage compost would be a marketable product that could be successfully produced by the local community.

Return to top

Chemistry and Biochemistry

Kyra Reznikov
Year 12, Annesley College, Glenalta, SA

'Breaking Down Protein'

Kyra has had a long-standing curiosity about enzymes since she studied the digestive system in Year 9. When Kyra discovered that proteases in meat tenderisers called Bromelain and Papain came from plants, she was intrigued at the notion that plants could effectively digest animal meat.

Kyra's study investigated the use of such enzymes in breaking down proteins. using cooked egg white as a source of protein, she compared the effectiveness of five fresh fruit juices against an animal protease, pepsin, and a commercial meat tenderiser product.

She carefully measured the time taken for the various enzymes to completely digest the egg white and change it to a colourless solution.

Her results found that kiwi fruit and pineapple juice had protease activity comparable to the commercial meat tenderiser. A particularly interesting finding was that under certain conditions, she found that kiwi fruit juice was even more effective.

Judges were also impressed with Kyra's intelligent use of the simple apparatus of test tubes and beakers.

Return to top

Environmental and Earth Science

Peter George
Year 11, Maitland Grossmann High School, Bolwarra, NSW

'At what Slope should Soil Tillage be Stopped to Prevent Substantial Erosion?'

Peter's study on the slop of soil tillage and its impact on soil erosion was inspired by the soil degradation he witnessed as a resident of the Hunter Valley Region.

After a period of intense reading and research, Peter developed his theory that the slope of soil influences the quantity of soil that erodes from a landscape.

Over a period of six days, peter tested different angles of soil tillage, simulating real conditions, including the type of annual rainfall experienced in the Newcastle area.

His excellent methodology and meticulous attention to detail resulted in some fascinating conclusions. Peter discovered that the slope of soil directly influences how much soil erodes away from the slope after rainfall. Specifically, he found that the point at which the soil loss dramatically increases is at 7 degrees.

Peter's research will provide interesting information for individuals or organisations concerned with landcare. He has made some valuable insights into an important problem which is detrimental to the environment and the Australian economy.

Return to top

Physics, Engineering and Material Science

Naomi Roediger
Year 10, Crestwood High School, Castle Hill, NSW

'Abseiling Descenders and Rope Wear'

Avid abseiler Naomi Roediger conducted a study on the equipment and rope used in the sport of abseiling.

Abseilers attach themselves to a rope with what is called a descender. There are many types of descenders which control the varying tension of the rope. The two most common are the figure 8, favoured by abseiling enthusiasts, and the in-line rack descender.

Naomi's objective was to test a commonly held view among the abseiling fraternity, that is, that the figure 8 descender causes more damage to an abseiling rope than the in-line abseiling descender.

With the help of family members, Naomi exposed four ropes to abseils using the figure 8 descender, and four using the in-line descender. After each abseil, the rope's breaking force, knotability, physical appearance and condition were tested and compared.

Judges were impressed with the initiative and precision of Naomi's many hours of testing an many hundreds of abseiling descents, along with the follow-up research she conducted in the laboratory. Naomi's findings show that the figure 8 descender actually causes marginally less deterioration to the rope than the in-line descender, proving the common belief to be incorrect.