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These engines used to______(start) by hand. Now they are started by electricity..
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Scientists have come up with a theory for why time flies when you are having fun and drags when you are bored. Scans have shown that (62) of activity in the brain change depending on how we focus on a task. Concentrating on time passing, as we do when bored, will (63) brain activity which will make it seem as though the clock is ticking more (64) . The research, by the French Laboratory of Neurobiology and Cognition, is published in the magazine Science. In the study, 12 volunteers watched an image while researchers (65) their brain activity using MRI(核磁共振成像) scans. Volunteers were given a (66) of tasks. In one they were told to concentrate simply on the duration of an image, in (67) they were asked to focus on the (68) , and in a third they were asked to concentrate on both duration and color. The results showed that a network of brain regions was (69) when more subjects were paid attention to duration. It is thought that if the brain is busy focusing on many aspects of a task, then it has to spread its resources thinly, and pays less (70) to time passing. Therefore, time passes without us really (71) it, and seems to go quickly. (72) , if the brain is not stimulated in this way, it concentrates its (73) energies on monitoring the passing of time. This may make time seem to (74) , but in fact it is probably a more accurate perception of reality. (75) the researchers found that the more volunteers concentrated on the duration of the images, the more (76) were their estimates of its duration.Lead researcher Dr. Jennifer Coull said many of the areas of the brain (77) in estimating time were the same that played a key role in controlling movement, and (78) for action. She said this overlap suggests that the brain may make sense of time as (79) between movements, in much the same way (80) musicians mark time with his foot, or (81) anticipate the sound of a starter’s pistol.
我国植物资源极为丰富，仅次于巴西，居世界第二位。( )
Text 2 Diamonds are best known as the "girl’s best friend" in rings, tiaras and the Pink Panther films. Yet the aesthetic uses for these sparklers are in the minority. Today, many diamonds are made synthetically for a vast range of uses, from surgeons’ scalpels to super-fast microchips. Labs produce 180 tonnes of diamond each year--almost nine times as much as comes out of the ground. And its strength, clarity and chemical resistance could make it the engineering material of the 21st century. Already, there are diamond heat sinks for tiny integrated circuits, diamond coatings on joint replacements and diamond windows on space probes. Soon, a diamond coating could protect your car gearbox, and super-strong diamond threads be used to reinforce ultra-light aircraft. Diamond is far more than just a pretty rock. It has an impressive list of properties. As the hardest material known to science, it is resistant to attack by strong acids and alkalis and is a superb conductor of heat. This all means that there are many uses for diamond apart from the purely decorative. Because it dissipates heat so well--much better than silicon, engineers want to build microchips on layers of diamond. They could then squeeze yet more electronic components into smaller areas without the circuit overheating, to produce a new generation of super-fast computers. The key to diamond’s extraordinary properties is its structure. Carbon can form four strong bonds with other molecules, which is why it forms the basis of so many organic compounds and is the building block of life. When four carbon atoms are linked together in a regular lattice, the result is a diamond crystal. Another form of carbon is the graphite in pencils. Companies such as De Beers and General Electric have been making synthetic diamonds since the early 1950s. Almost any substance rich in carbon can be converted into diamond. General Electric chemist Robert Wentorf once made diamonds from peanut butter. A newer process, chemical vapour deposition(CVD), is used to produce ultra-hard diamond coatings. CVD used high temperatures but low pressures to coat a substance with carbon vapour, as a layer of small diamond crystals. These crystals will eventually join together and can be used to create huge gems. Diamonds such as this are usually sliced up to produce long scalpels or other tools. CVD has scientists excited. "For the first time, we have all the superlative properties of diamond in a form that’s useful for engineering applications." Says May, who uses CVD to create diamond threads by coating tungsten wire. So it seems that diamonds are not just a girl’s best friend, but an engineer’s too. Which of the following best explains what makes diamond a good engineering material
Yet with economies in free fall, managers also need up-to-date information about what is happening to their businesses, so that they can change course rapidly if necessary. Cisco, an American network-equipment giant, has invested over many years in the technology needed to generate such data. Frank Calderoni, the firm’s CFO, says that every day its senior executives can track exactly what orders are coming in from sales teams around the world, and identify emerging trends in each region and market segment. And at the end of each month, the firm can get reliable financial results within four hours of closing its books. Most firms have to wait days or even weeks for such certainty. Admittedly, Cisco’s financial results have not made happy reading recently because, in common with many other large technology companies, it has seen demand for its products decline in the downturn. In early February it announced that its fiscal second-quarter revenues of ＄9.1 billion were 7.5% lower than the same period in 2008 and that its profit had fallen by 27%, to ＄1.5 billion. In response to hard times, Cisco plans to cut ＄1billion of costs this year by, among other things, making use of its own video-conferencing and other communications technologies to reduce the amount its executives travel. It is also using these facilities to relay information from employees on the ground to its senior managers, and to get instructions from Cisco’s leaders back out to its 67,000 staff. A rapid exchange of information and instructions is especially valuable if the company wants to alter course in stormy times. If everybody in a company can rapidly grasp what they have to do and how it is changing, they are more likely to get the job done. But some firms are reluctant to share their goals with the wider world. Unilever, a big Anglo-Dutch consumer-goods group, has decided against issuing a 2009 financial forecast to investors, arguing that it is difficult to predict what is going to happen, given the dangerous state of the world economy. "We’re not just going to provide numbers for the sake of it," explains James Allison, the company’s head of investor relations. Other companies that have decided not to provide annual earnings estimates for 2009 include Costco, a big American retailer, and Union Pacific, an American railway company. Some firms, such as Intel, seem to have chosen to take things quarter by quarter. The giant chipmaker (芯片制造商) said in January that it would not issue an official forecast for the first quarter of 2009 after its fourth-quarter 2008 profit decreased by 90%. Several retail chains have also stopped providing monthly sales estimates because they cannot see what the future holds. Retailers, chipmakers and firms in many other industries may have a long wait before the economic fog finally lifts. What can we know about the giant chipmaker-- Intel in the passage
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