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【单选题】
Li-Fi, an alternative to Wi-Fi that transmits data using the spectrum of visible light, has achieved a new breakthrough, with UK scientists reporting transmission speeds of 10Gbit/s—more than 250 times faster than superfast broadband. The fastest speed【C1】______reported was 3Gbit/s, achieved earlier this year in Germany. Chinese researchers also claimed this month to have【C2】______a 150Mbp/s connection, but some experts were doubtful without seeing further【C3】______ The term Li-Fi was【C4】______by Edinburgh Universitys Prof Harald Haas【C5】______the technology is also known as visible light communications (VLC). Many experts claim that Li-Fi represents the future of mobile internet【C6】______its reduced costs and greater efficiency compared to traditional Wi-Fi. Both Wi-Fi and Li-Fi transmit data【C7】______the electromagnetic spectrum, but【C8】______Wi-Fi utilizes radio waves, Li-Fi uses visible light. This is a【C9】______advantage in that the visible light is far more plentiful than the radio spectrum (10,000 times more in fact) and can achieve far greater data【C10】______Li-Fi signals work by【C11】______bulbs on and off【C12】______quickly—too quickly to be noticed by the human eye. This most recent breakthrough builds upon this by using tiny micro-LED bulbs to【C13】______several lines of data in parallel. The research was carried out by the Ultra Parallel Visible Light Communications project, and funded by the Engineering and Physical Sciences Research Council. Existing LED light bulbs could be【C14】______to transmit Li-Fi signals with a single microchip, and the technology would also be of use in situations where radio frequencies cannot be used for fear of【C15】______with electronic circuit. And although Li-Fi bulbs would have to be kept on to transmit data, the bulbs could be【C16】______to the point that they were not visible to humans and yet still【C17】______. One draw-back is that the data receiver would have to be in sight of the transmitter-bulb as visible light does not【C18】______solid materials. The makers of Li-Fi note that this quality might actually be an advantage in some【C19】______making Li-Fi more【C20】______than Wi-Fi with hackers unable to access unsecured internet connections from out of sight of the transmitter. 【C1】
A.
subsequently
B.
presently
C.
lately
D.
previously
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参考答案:
举一反三
【单选题】济川煎的君药是
A.
肉苁蓉
B.
甘遂
C.
大黄
D.
附子
E.
芒硝
【单选题】恶性淋巴瘤最常见的临床表现是
A.
肝肿大
B.
脾肿大
C.
无痛性淋巴结肿大
D.
发热
E.
皮疹
【多选题】新形势下,要深刻认识党面临的( )的尖锐性和严峻性。
A.
精神懈怠危险
B.
能力不足危险
C.
脱离群众危险
D.
消极腐败危险
【单选题】深刻认识党面临( )的尖锐性和严峻性,坚持问题导向,保持战略定力,推动全面从严治党向纵深发展。
A.
精神懈怠危险、能力不足危险、脱离群众危险、消极腐败危险
B.
精神懈怠危险、封闭僵化危险、脱离群众危险、消极腐败危险
C.
精神懈怠危险、能力不足危险、官僚主义危险、消极腐败危险
D.
精神懈怠危险、能力不足危险、脱离群众危险、作风腐化危险
【单选题】济川煎的君药是
A.
当归
B.
牛膝
C.
枳壳
D.
肉苁蓉
E.
升麻
【单选题】深刻认识党面临( )的尖锐性和严峻性,坚持问题导向,保持战略定力,推动全面从严治党向纵深发展。
A.
精神懈怠危险、能力不足危险、脱离群众危险、消极腐败危险
B.
精神懈怠危险、封闭僵化危险、脱离群众危险、消极腐败危险
C.
精神懈怠危险、能力不足危险、官僚主义危险、消极腐败危险
D.
精神懈怠危险、能力不足危险、脱离群众危险、腐化堕落危险
【多选题】恙虫病的临床特点包括
A.
焦痂与溃疡
B.
淋巴结肿大
C.
皮疹
D.
肝脾大
E.
高热
【单选题】济川煎的君药是
A.
当归
B.
牛膝
C.
枳壳
D.
肉苁蓉
【单选题】下列关于恙虫病临床表现的描述,错误的是
A.
焦痂与溃疡
B.
淋巴结肿大
C.
皮疹
D.
肝脾肿大
E.
关节肿痛
【单选题】某患者,腿部皮肤被叮咬,局部出现溃疡,伴高热,皮疹,淋巴结肿大,肝脾肿大。外斐反应:抗体效价1:320。该病的传播媒介可能是()
A.
人虱
B.
鼠虱
C.
恙螨
D.
E.
蚊子
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