Week In Science

Matt Kaplan published an article in the June 29, 2007 edition of 'Nature' (Urine grows better fish food) in which he highlighted evidence that diluted human urine facilitates the growth of plankton. The data originated at the University of Kalyani in India through the efforts of Bara Bihari Jana and his colleagues. The university urinals were the source of the urine. There were also points of comparison as cow urine was also used and mixtures created with earthy ingredients that included vermin compost, poultry droppings and cow dung. There was a guiding formula as well. To every 4,500 litres of water a half a liter of urine was added or a half a kilo of dung.

There must be something to say for human urine because the plankton nourished with it reproduced at least four days earlier than plankton nourished with competing cocktails. Environmental biochemist Stephen Smith, of Imperial College in London, pointed out that human urine has two advantages: it is stable and has valuable nutrients. He also confirmed the obvious advantages of using it to spur the growth of plankton; cautioning though against urine contaminated by individuals taking medication or antibiotics.

The Indian group detailed the beneficial components of human urine which include nitrogen compounds that are highly concentrated. These compounds, when broken down, release amino acids and minerals.

Human urine also offers an economic advantage in that it is cheaper than chemical fertilizers. It also seems to be more environmental friendly. The erosion of fertilizers from land- eutrophication- would be less if urine were used. Eutrophication damages plankton in rivers, lakes and seas.

Plankton is an important part of earth's ecosystem. Culturing planktonic fish food is big business.

Another liquid solution of note is that of liquid hydrogen. 'Nature' features an article authored by Katharine Sanderson entitled 'Hydrogen fuel goes liquid' which was published online on August 24, 2007. The article cites the possibility, raised by Robert Crabtree of Yale University in New Haven, Connecticutt, that in the future hydrogen released from an organic liquid will be pumped into cars and burned. Water would be the byproduct. Since current vehicle fuels are in liquid form, there is an existing supply infrastructure geared to the storage and pumping of liquids which could facilitate a transition. Gaseous hydrogen, on the other hand, could entail a greater adjustment.

Week in Science recently featured the article Fill the Tank with Water Please which cited research into the possibility of extracting hydrogen from water in the presence of an alloy consisting of aluminum and gallium. The competing emerging technologies, which include gaseous hydrogen, underscore the environmental and economic significance of a viable hydrogen fuel source to replace fossil fuels.

The innovative breakthrough that could allow for freeing hydrogen from a liquid fuel at operable temperatures is the inclusion of nitrogen within organic liquids. Bonds between hydrogen and nitrogen are weaker than those between hydrogen and carbon. This facilitates the extraction of hydrogen through catalysis at lower temperatures. When the hydrogen containing liquid is depleted of its hydrogen it would be removed and be rehydrogenated for reusage. The repeated cycle would be a fixture of a new industry.