空调管道温度用控制面板旋钮控制无效时,一般不需要检查以下哪个部分() A.混合活门工

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问题:

空调管道温度用控制面板旋钮控制无效时,一般不需要检查以下哪个部分()

A.混合活门工作情况

B.温控系统传感器和控制盒

C.35华氏度控制系统

D.再循环风扇

考点:飞行员执照考试737NG机型航空理论知识737NG机型航空理论知识题库
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一条弦把圆分成1:3两部分,则弦所对的圆心角为______度.

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雇主责任保险的附加医疗费保险是承保雇员在保单有效期间内因()所需要的医疗费用。

A.职业病

B.意外事故

C.职业病以外的疾病

D.职业病及意外事故

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在消解浸出液时,加硝酸后应在()状态下蒸发至近干。

A.低温

B.近沸

C.180℃

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医患沟通的基本原则有哪些?

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If phone calls and web pages can be beamed through the air to portable devices, then why not electrical power, too It is a question many consumers and device manufacturers have been asking themselves for some time. But to seasoned observers of the electronics industry, the promise of wireless recharging sounds depressingly familiar. In 2004 Splashpower, a British technology firm, was citing “very p” interest from consumer-electronics firms for its wireless charging pad. Based on the principle of electromagnetic induction (EMI) that Faraday had discovered in the 19th century, the company’s “Splashpad” contained a coil that generated a magnetic field when a current flowed through it. When a mobile device containing a corresponding coil was brought near the pad, the process was reversed as the magnetic field generated a current in the second coil, charging the device’ s battery without the use of wires. Unfortunately, although Faraday’s principles of electromagnetic induction have stood the test of time, Splashpower has not — it was declared bankrupt last year without having launched a single product.

Thanks to its simplicity .and measurability, electromagnetic induction is still the technology of choice among many of the remaining companies in the wireless-charging arena. But, as Splashpower found, turning the theory into profitable practice is not straightforward. But lately there have been some promising developments.

The first is the formation in December 2008 of the Wireless Power Consortium, a body dedicated to establishing a common standard for inductive wireless charging, and thus promoting its adoption. The new consortium’s members include big consumer-electronics firms, such as Philips and Sanyo, as well as Texas Instruments, a chipmaker.

Fierce competition between manufacturers of mobile devices is also accelerating the introduction of wireless charging. The star of this year’s Consumer Electronics Show held in Las Vegas was the Pre, a smart-phone from Palm. The Pre has an optional charging pad, called the Touchstone, which uses electromagnetic induction to charge the device wirelessly.

As wireless-charging equipment based on electromagnetic induction heads towards the market, a number of alternative technologies are also being developed. PowerBeam, a start-up based in Silicon Valley, uses lasers to beam power from one place to another.

It now seems to be a matter of when, rather than if, wireless charging enters the mainstream. And if those in the field do find themselves languishing in the disillusionment, they could take some encouragement from Faraday himself. He observed that “nothing is too wonderful to be true if it be consistent with the laws of nature.” Not even a wirelessly rechargeable iPhone.

What does the author mean by the last sentence of the passage()

A. Wireless recharging is too wonderful to be true

B. Wireless recharging is consistent with the laws of nature

C. Wireless recharging will definitely come true finally

D. Wireless recharging will surely enter the mainstream in the end

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