With a large, bright screen and inability to remove the battery in the iPhone 4, getting a secondary power source is inevitable if you can't guarantee a power point on your travels.

旅行时没法充电，iPhone 4屏幕硕大闪亮，再加上内置电池无法取出，是时候准备一个备用电源了。

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Note that the system does not show the battery dropping from 100% until well over an hour of unplugged use, at which point it starts to steadily decline.

从中可以看出，系统记录中并没有显示电量一开始就从100%下降，而是经过一个小时后才开始下降，此后电量稳步下降。

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To find out, the two researchers gave 208 undergraduates a battery of trolleyological tests and measured, on a four-point scale, how utilitarian their responses were.

为了探明这一问题，这两位研究者给208位大学生做了一连串的电车测试并以四探针测试仪那样的精细程度检测他们反应的实用主义程度几何。

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The two-tonne bell was cast in about 1938 for the lighthouse at Battery Point, Portishead, near Bristol.

BBC: Battery Point lighthouse

In back, the collapsible zoom lens, xenon flash, and aluminum battery cover mimic a point-and-shoot camera.

ENGADGET: Aigo A8 / Leo 14 megapixel cameraphone hands-on (video)

The company reckons the new transistors, which should be available later this year, will consume half as much power as its existing offerings, making them particularly suitable for mobile computing, where battery life is an important selling point.

ECONOMIST: Transistors