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呼和浩特市做隆胸多少钱呼和浩特治疗腋臭的医院呼和浩特自体脂肪填充价格 Display screens显示屏Going through a phase相转变A new way to create electronic images新的电子图案显示方法Wave of the future?未来之波LIQUID-CRYSTAL displays are a familiar and ubiquitous technology. But if Harish Bhaskaran of Oxford University is right, their days may be numbered. The essential feature of LCDs is that the pixels in them switch between amorphous and crystal-like phases, which changes their optical properties. In a paper in this weeks Nature, Dr Bhaskaran and his colleagues describe something similar in a solid material. At the least, that would stop the messy abstract-impressionist patterns which happen when an LCD is dropped too hard. At most, it might open up a new range of applications, from clothes that change colour to dimmable windscreens.液晶显示屏是一项成熟而广泛应用的技术。但如果牛津大学的Harish Bhaskaran的想法实现,液晶屏的好景也就没几天了。LCD的基本特征是其像素在非晶相和类晶相间转化,因此改变其光学性质。在本周的《自然》杂志上,Bhaskaran士及其同事陈述了一种类似的固体材料。至少该材质可以防止当LCD猛烈坠地后产生麻烦的抽象印象派图案。最理想情况下,它会有新的应用范围,从变色布料到可调光挡风玻璃。Solid phase-change materials are aly used to store data in optical memory disks. They are also being considered for use in memory chips, because the switch between amorphous and crystalline states alters their electrical properties in ways that can store electronic bits of data. Dr Bhaskaran, though, has shown that thin enough films of the right sort of material can be made to change colour, too.固态相变材料已经用于在光储存盘中储存数据。也可能被用于记忆芯片,因为其非晶态和晶态之间的转变也改变了其电学性能,因此他们能储存电子数据。然而,Bhaskaran士展示了一种特定材料膜,在足够薄的情况下也可以改变颜色。This property would make them suitable both for displays that rely on reflected light (so-called electronic paper) and the older, backlit sort that rely on transmitted light. The resulting displays would be thin and could be flexible if printed on the right material—increasing the range of applications they might be used in. And they would consume little power, since energy need be used only when a pixel has to be flipped from one phase to another.这一性能将使其适合于反射光显示(所谓电子纸)和早期的依赖透射光的背光显示。所得显示屏不仅薄,而且铺在合适材料上时非常灵活,增加了其应用范围。而且它消耗的功率更少,因为这种材料只需要在变相的时候消耗能量。The researchers material of choice is an alloy of germanium, antimony and tellurium. Both the crystalline and the amorphous phases of this substance are stable at any temperature a device is likely to experience, and thin films of it are more or less transparent. The power needed to effect the phase change could be fed to individual pixels by electrodes made of indium tin oxide, which is also transparent.研究人员选择的材料是镓、锑和碲合金。这一物质的晶态和非晶态在任何设备适用温度下都很稳定。其薄膜也几乎透明。要激发相转变所需的能量可以由透明的铟锡氧化物电极向单个像素提供。The colour of a pixel would depend not only on its phase, but also on its thickness, which would affect the way light waves being reflected within it interfere with one another, cancelling out some frequencies while amplifying others. (The effect is similar to the creation of colours by a thin layer of oil on a puddle.) Generally, the alloy layer needs to be thinner than 20 nanometres for that to happen.单个像素的颜色不仅取决于其相态,也同其厚度有关。厚度会影响光波在两个像素间界面处的反射,削弱部分频率,加强其他频率。(此效应类似于池塘表面薄油层产生的色。)一般来说,合金层需要薄于20 nm才会发生这一现象。To demonstrate their idea, the researchers sprayed films of their alloy onto pieces of silicon, quartz and plastic. They then used a device called an atomic-force microscope, which has a tip a few nanometres across, to apply appropriate electric currents in a grid pattern across the films surface. This grid mimicked an array of pixels, creating a stable pattern. The result, as their picture of a Japanese wave shows, is a recognisable image—if not, yet, a perfect one.为了明其观点,研究人员将其合金铺覆到硅,石英和塑料上。然后他们使用所谓原子力显微镜的设备来施加合适的电流在横穿膜表面的网格上。原子力显微镜尖端仅有几个纳米大小。网格模仿像素排列,产生稳定的模式。他们对日本电波的拍摄结果是一个可识别的图像,即便不可识别,也是非常完美的。Adding the indium-tin-oxide electrodes is a more complicated process, but to show it can be done in principle, Dr Bhaskaran has made a single pixel this way. Whether his idea will get off the lab bench and into the shops remains to be seen. It is by no means the only suggestion around for a new generation of display screens. But it looks plausible.加入铟锡氧化物电极是更为复杂的过程,但是可以从原理上展示其过程。Bhaskaran用这种方式制备了单个像素。他的想法能否从实验室走进商用还是未知。这绝不是新一代显示屏的唯一方案,但颇得看好。翻译:赵兴昊译文属译生译世 /201505/377287If you ever get a chance to meet a sea lamprey, you wont forget it.They look like an eel but theyre actually a fish. They have a suction cup for a face, with hundreds of razor sharp teeth.;And they will sucker onto a fish and actually rasp a hole through the fishs skin and scales and actually feed off the blood and body fluids of the host fish,; says Aaron Jubar. Hes with the U.S. Fish and Wildlife Service in Ludington.A threat to the lakesSea lampreys devastated the Great Lakes fishery in the middle of the last century, and were still battling them today.;We estimate a single sea lamprey in the Great Lakes can destroy up to 40 pounds of Great Lakes fish through its parasitic life which is only about 18 months,; Jubar says.They love to feed on lake trout, salmon, whitefish and steelhead - the prize fish at the top of the food web in the Great Lakes.Combating the parasiteWe spend more than million in federal money each year to control the lampreys (according to the Great Lakes Fishery Commission, .9 million goes to sea lamprey control measures and more than million is spent on sea lamprey research). A big part of that control program is finding out where the lampreys hide out when theyre little.On the day I join Aaron Jubar and his team to go lamprey hunting in the Clinton River in Macomb County, theyre wearing waders and gloves and they have metal contraptions strapped to their backs. They look like Ghostbusters.;What were using today is our backpack electro-fishing units and these are specially designed to capture sea lamprey larvae,; Jubar says.The backpacks send an electric current down through two metal probes. The crew members move these through the water looking for lampreys.;And then that low pulse agitates them so they come shooting out of their burrows and when we see them, then we can high pulse and that actually completely immobilizes them and then we can scoop them up,; he says.Im in waders so I can get in the river too, but Jubar warns me not to touch the water.;You would definitely feel it, the low pulse would be a sharp tingling; the high pulse, youd feel that shoot up your arm,; he says.The continuous fightJason Krebill is stirring up the muck at the bottom of the Clinton River.;Looks like I got a crayfish,; he says.Hes been chasing lamprey larvae for 15 years now.;Yeah, theyre ugly, but in the same regard, functionally, theyre kind of beautiful, you know?; he says. ;As far as parasites go, theyve pretty much got it down. They get a free meal and a free ride for the majority of their life. I think they sacrifice looks for smarts.;The U.S. lamprey hunting teams do 2,000 of these surveys all over the Great Lakes region every summer. And there are more of these teams on the Canadian side. Theyre trying to find out where the lampreys are. If they find them, different crews come out and kill the lampreys with a lampricide.Jubar says theyre constantly trying to knock back their numbers. Its a battle thats been going on since the late 1950s.;Theyre a lot like cockroaches,; he says. ;You leave two behind, you have a problem, because the females can have up to 100,000 eggs. So just one female and one male can infest this whole stream potentially.;He says theyre keeping the sea lampreys in check in most of the Great Lakes. But in the past six years, lampreys have been booming in Lake Erie. In , Jubar says they estimated there were about 30,000 sea lampreys in the lake.;In 2014, we estimated just over 14,000 sea lampreys in Lake Erie so, were still five times above our target levels,; he says.He says the St. Clair River is probably a big part of this puzzle. Jubar says they estimate there are more than 900,000 baby lampreys in that river.He says as the St. Clair and Detroit Rivers have gotten cleaner, theyve become better habitat for lampreys.In addition, he says the lake trout and steelhead fisheries are doing very well in the eastern basin of Lake Erie, so theres more of the lampreys favorite food available.We turn up empty handed on this lamprey hunt. But Jubar says thats actually a good thing.;Weve never found them up this far, but we are very vigilant,; he says.And theyll keep doing this work, every single summer, to try to stay on top of this expensive, blood-sucking parasite.201506/381760呼和浩特京美整形美容医院双眼皮怎么样

呼和浩特赛罕区去蝴蝶斑多少钱呼和浩特市中医医院做双眼皮开眼角手术多少钱 呼和浩特整形医院哪里好

乌兰察布市丰胸医院哪家好Time to break out the long pants: tick season is back!The past couple of years weve had a tick boom along the west side of the state and its happening again this year.Rich Keith spends a lot of time with ticks. Hes the director of the Kalamazoo Valley Bird Observatory. He and his wife Brenda have been doing tick surveys every year since 1997 for university researchers in Michigan and elsewhere.;In 2003-2007, it was documented that a new expansion of the blacklegged tick came up from northern Indiana all the way to Sleeping Bear Dunes,; says Keith.Symptoms of Lyme diseaseFoster says the primary symptoms of Lyme disease include a febrile illness.;So this would be fever, headaches, malaise, swollen lymph nodes. It might also include joint pain and swelling and muscle pain,; he explains.But he says the most obvious symptom associated with Lyme disease is the ;erythema migrans; or ;bullseye rash.; This non-itchy, reddish rash expands out from the site of where the tick bites after a few days. According to the CDC, it occurs in 70-80% of people infected with Lyme disease.Foster says if you have an onset of these types of symptoms in the summer months and you know youve been to an area where these ticks occur, go see a health care provider. Early treatment for Lyme disease is essential in making sure that you go through a full recovery.How concerned should you be about tick bites?Lyme disease is a bacterial infection and not every tick is infected.;Really it is only the blacklegged tick in Michigan that transmits Lyme disease and theres only a certain percentage of these ticks that are even infected with the bacteria,; said Foster.He says studies in Michigan show about 15-25% of blacklegged ticks in the nymph stage and 40-45% of adult blacklegged ticks are infected.The number one way to reduce ones risk of contracting the illness is to avoid tick bites. Foster recommends wearing EPA-approved insect repellents that contain DEET, picaridin or oil of lemon eucalyptus.When in the woods or other tick-prone areas, wear long pants and tuck those pants into your socks to reduce the risk of ticks crawling up your pant leg.Foster also recommends hiking in the center of trails to avoid brushing up against plants on the edges where ticks like to hang out.;Secondly, doing a tick check on your family members and taking a shower soon after coming indoors will help to wash off ticks that may have not bitten you yet,; he says.He says if a tick is attached to your body for less than 24 hours, your chance of getting Lyme disease is very small.But Foster warns that this time of year, you need to really look carefully when youre doing a tick check.;The blacklegged tick stage that is out there – in the wild – thats coming up right now is called the nymphal-stage tick and it is very, very small, about the size of a poppy seed,; says Foster. ;So a lot of times people dont see these when theyre climbing on their bodies and you dont feel them bite you.;He recommends checking all over your body for ticks, paying special attention to certain areas of your body where ticks commonly bite: behind the knee, the waistline, groin, armpits, behind the ears, around the neck and in the hairline.Pets can be carriers of infected ticksKim Signs with MDCH says you can do a tick check on your dog or cat. Ticks especially like to hang out around the ears and in between the toes.She recommends talking with your vet about ways to keep ticks off your pet in the first place.Signs says that dogs are susceptible to Lyme disease but theres a vaccine for them. She says it can be hard to tell if your dog has the illness, but it can cause fever and swollen joints. So, if you notice changes in your dogs behavior, she says its a good idea to take it to the vet.The state of Michigans Emerging Disease site has updated its brochure, Ticks and Your Health, in an effort to inform residents about the dangers of tick bites.You can also check out the CDCs tick site for more info.201505/377142 呼和浩特全身抽脂的价格内蒙古自治区第二附属医院整形科



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