Producing ethanol from corn is relatively easy: The corn’s abundant sugars are readily fermented into alcohol. But using what is essentially a food crop to produce fuel has been criticised as a misuse of resources that can harm both agriculture and the environment. Better, critics say, to make what is called cellulosic ethanol from leaves and stalks or other crop waste or nonfood crops like switchgrass. The process uses lignocellulose, the basic structural material of all plants and the most abundant organic compound on the planet.
But cellulosic ethanol is more difficult to make. The lignocellulose must first be broken down into sugars, which can then be fermented. Current techniques use costly enzymes or highly concentrated acids that are difficult to handle.
Now, Ronald T Raines and Joseph B Binder of the University of Wisconsin are proposing a different way. In a paper in The Proceedings of the National Academy of Sciences, they describe a process that uses an ionic liquid, a salt with a low melting point, in combination with water and acids at lower concentrations to produce fermentable sugars. The researchers found that water was the key to making the process efficient. Without water, the sugars produced by the action of the ionic liquid and the acid rapidly degraded into other compounds. But water keeps chloride ions in the salt from further reacting with the sugars.
Henry Fountain
NYT News Service

These insects dislike the English weather
Jane Hill, biology professor from the UK’s University of York and scientists from Rothamsted Research in the UK have for the first time used radars to unveil the sophisticated flight behaviour of insects, published in the journal Science. The radars emit a stationary beam upwards that can detect individual insects as they migrate between heights of 200m and a kilometre above them. The radars measure the size of the insect, its height of flight and its speed and direction of movement.
Using radar data for more than 100,000 individual insects, collected from 569 mass migrations in spring and fall, scientists have examined the flight behaviour of four groups of migratory insects: moths (Autographa gamma and Noctua pronuba), hawkmoths (Sphingids) and butterflies (Hedylids). These insects dislike the English weather to the extent that they flock all the way to the Mediterranean basin in winters and return to the UK during spring. A distance of 4,000 km is covered in just 40 hours; some of the tiny butterflies are barely 15 mm in length and live for just a few days.
Another feature about their journeys is the insects know how to identify the winds most helpful in moving them in the right direction. In the northern hemisphere, the insects use very fast-moving winds to achieve rapid, long-distance transport northwards in spring and southwards in autumn. The inbuilt compass helps them choose the right direction as they travel at a speed of up to 100 km per hour. Although the insects travel downwind, they do make subtle adjustments to their movements so as to not let the winds drift them away from their preferred direction.
Tiasa Adhya
Down To Earth Feature Service

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