LEEKE是也 LEEKE是也
发型好不好看,取决于脸。
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其实结果并不像想的那么乐观,昨天比赛裁判因素其实是可以预见到 其实结果并不像想的那么乐观,昨天比赛裁判因素其实是可以预见到的,易建联自带哨子,裁判加持,排除这些不说,昨天第四节从王化东那个伪体(本不存在)开始,辽宁队整体是懵的,杜锋是冷静的,毕竟经历了十几个总决赛,这时候他发现辽宁队威胁最大的是梅奥,当时梅奥是冷静的,他是辽宁队在第四节取胜的唯一可能,这时候迅速上炮灰垫脚,把最后唯一冷静的那一个干急了,把本就支离破碎的比赛弄得更乱,当梅奥再次恢复冷静的时候,苏伟开始上脚了。这还没完,就算这样还是有拿下的希望,这时候刘不投,加上郭高的一次看重叠站位彻底没戏了,不是站着说话不腰疼,辽宁队队员心理素质还是嫩。以前觉得杜锋是个没啥能力的教练,现在不得不说,脑子清醒,审时度势,国内现在除了李春江没谁有这脑子了。我得出的结论就是第三节已经输了,输在教练,大韩在四犯的时候已经不敢伸手防守了,这个时候需要大韩进攻,结果没给他制定战术,放手不敢伸手,那还留在场上干嘛?不是说要换下大韩,进攻端是不是多打打?结果把郭艾伦累拉胯了,被赵瑞一步过,真是没劲了,所以嘛,马丁滚,找个老资历的辽宁教练吧,最起码关键时刻能稳住。
Scientists slow down the speed of light travelling through air Issued: Fri, 23 Jan 2015 00:01:00 GMT Scientists have long known that the speed of light can be slowed slightly as it travels through materials such as water or glass. However, it has generally been thought impossible for particles of light, known as photons, to be slowed as they travel through free space, unimpeded by interactions with any materials. In a new paper published in Science Express today(Friday 23 January), researchers from the University of Glasgow and Heriot-Watt University describe how they have managed to slow photons in free space for the first time. They have demonstrated that applying a mask to an optical beam to give photons a spatial structure can reduce their speed. Their experiment was configured like a race, with two photons released simultaneously across identical distances towards a defined finish line. The team compare a beam of light, containing many photons, to a team of cyclists who share the work by taking it in turns to cycle at the front. Although the group travels along the road as a unit, the speed of individual cyclists can vary as they swap position. The group formation can make it difficult to define a single velocity for all cyclists, and the same applies to light. A single pulse of light contains many photons, and scientists know that light pulses are characterised by a number of different velocities. The researchers found that one photon reached the finish line as predicted, but the structured photon which had been reshaped by the mask arrived later, meaning it was travelling more slowly in free space. Over a distance of one metre, the team measured a slowing of up to 20 wavelengths, many times greater than the measurement precision. The work demonstrates that, after passing the light beam through a mask, photons move more slowly through space. Crucially, this is very different to the slowing effect of passing light through a medium such as glass or water, where the light is only slowed during the time it is passing through the material – it returns to the speed of light after it comes out the other side. The effect of passing the light through the mask is to limit the top speed at which the photons can travel. The work was carried out by a team from the University of Glasgow’s Optics Group, led by Professor Miles Padgett, working with theoretical physicists led by Stephen Barnett, and in partnership with Daniele Faccio from Heriot-Watt University. Daniel Giovannini, one of the lead authors of the paper, said: “The delay we’ve introduced to the structured beam is small, measured at several micrometres over a propagation distance of one metre, but it is significant. We’ve measured similar effects in two different types of beams known as Bessel beams and Gaussian beams.” Co-lead author Jacquiline Romero said: “We’ve achieved this slowing effect with some subtle but widely-known optical principles. This finding shows unambiguously that the propagation of light can be slowed below the commonly accepted figure of 299,792,458 metres per second, even when travelling in air or vacuum. “Although we measure the effect for a single photon, it applies to bright light beams too. The effect is biggest when the lenses used to create the beam are large and when the distance over which the light is focused is small, meaning the effect only applies at short range.” Professor Padgett added: “It might seem surprising that light can be made to travel more slowly like this, but the effect has a solid theoretical foundation and we’re confident that our observations are correct. “The results give us a new way to think about the properties of light and we’re keen to continue exploring the potential of this discovery in future applications. We expect that the effect will be applicable to any wave theory, so a similar slowing could well be created in sound waves, for example.” The team’s paper, titled ‘Spatially Structured Photons that Travel in Free Space Slower than the Speed of Light’, is published in Science Express, which provides electronic publication of selected papers in advance of print in the journal Science.http://tieba.baidu.com/mo/q/checkurl?url=http%3A%2F%2Fwww.gla.ac.uk%2Fnews%2Fheadline_388852_en.html&urlrefer=ed0e64af132681a119a209e98f9d38f3
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