Question

THE idea came to Ralph Liedert while he was sweating in the Californian sunshine, having been standing with his daughter for over an hour in a queue for a ride at Disneyland. What, he thought, if his T-shirt had a cooling system he could turn on, at the tap of a smart phone app, when he needed it. Luckily, Mr Liedert does have the means to make the dream reality, for he works at the VTT Technical Research Centre of Finland, as one of a team there studying the rapidly growing field of microfluidics (微流控技術(shù)).

Cooling vests already exist (used by racing drivers, motorcyclists and people who work in hot conditions). But the tubes through which the cooling water is being pumped, and the vests’ need to be connected to outside units that cool this water, make them huge and clumsy. Mr Liedert thought VTT’s microfluidics department could do things better.

As its name suggests, microfluidics is the art of building devices that handle tiny amounts of liquid. Inkjet-printer cartridges (噴墨打印機墨盒) are a familiar example. Less familiar, but also important, are “l(fā)abs-on-a-chip” (芯片實驗室). These are tiny analytical devices that transport fluids such as blood through channels half a millimetre or less in diameter (直徑), in order to carry them into what holds analytical reagents (試劑). Sensors, then detect the resulting reactions and provide an instant analysis of a sample (樣本). Designing labs-on-a-chip is the VTT microfluidics department’s day job. One of its chips, for example, can tell whether water is affected by the bacteria that cause Legionnaires’ disease.

The department’s biggest contribution to the field, though, is to have developed a way of printing microfluidic channels onto large rolls of thin, flexible plastic. It works by passing the plastic between two heated rollers, one of which contains raised outlines of the required channels. As the rollers squeeze the plastic they create a pattern of channels into one surface. A second plastic film is then melted over the top as a cover. This process might, thought Mr Liedert, be suitable for printing a microfluidic cloth that was thin enough and pleasant enough to wear as a cooling vest.

The group’s first model showed that such a material could indeed be made and used to circulate cooled water. They are also looking at ways the water being circulated through the microchannels might be cooled. They have identified two. One uses a small heat-exchanger, the details of which they are keeping secret at this stage. The other employs evaporation (蒸發(fā)). It thus works in the same way that heat from circulating blood is removed by the evaporation of sweat.

Whichever cooling system is applied, the electronics needed to power and control it would be shrunk into a small package contained on the back of the vest. This could be operated by hand or, as Mr Liedert originally envisaged in his Californian queue, by a wireless link to a smart phone. Moreover, what can cool down can also, if run in an opposite way, warm up. In Finland, where winter temperatures fall as far as -50°C, that might be the technology’s killer app.

1.Microfluidics has been used in ______.

A. racing cars B. printing industry

C. testing material D. clothing industry

2.We can learn from the passage that ______.

A. VTT is a company which mainly works on the research into microfluidics

B. the new cooling vest of VTT will be smaller and work more effectively

C. the technology of microfluidics may have a positive effect on medical science

D. heat-exchanger as well as the way of evaporation will be used to cool the wearer

3.______ plays the key role in making the new cooling vest.

A. The special cloth B. The cooling system

C. The tiny liquid D. The wireless link

4.The underlined word “envisaged” most likely means _____ .

A. imagined B. discovered C. viewed D. planned

Answer 1