Under scanning electronic microscope, four kinds of metal structure may be observed including black core phase, white core phase, gray ring phase and white adhesion phase.

在扫描电子显微镜下可观察到四种金相组织：黑色芯相、白色芯相、灰色环形相和白色粘结相。

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That, for me, sums up the seductive intellectual core of computers and computer programming: here is a magic black box.

这对我来说，构成了有吸引力的计算机和计算机语言的核心：这是一个黑色的魔法盒子。

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Our own galaxy, the Milky Way, has a colossal black hole at its core, too, which is some three million times the mass of our Sun.

BBC: NEWS | Science/Nature | Deepest X-rays tell merger story

The DA has been through numerous re-branding exercises since its origins in the anti-apartheid movement of the 1970s and 80s, but in the eyes of some people it remains a "white" party, led by a white woman, Helen Zille, and somehow out of touch with the core values of black South Africans.

BBC: Is the ANC losing its grip on South Africa?

Carnivore works as a "black box" attached to the core of ISP networks.

CNN: Justice Department mum about who will review 'Carnivore'