地下水中物质的对流-扩散是水化学找油的理论基础。

The convection-diffusion of substances in subsurface waters is the theoretical basis for hydrochemical exploration of oils.

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将混凝土混合物倒入大海后立即开始硬化过程，而且该物质非但不会在水中溶解，还保持坚硬耐久。

Pouring concrete mixture into the sea immediately started the hardening process and rather than just dissolving in the mass of water, the substance was tough and long-lasting.

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测试显示水中污染物质的含量很高。

Tests have shown high levels of pollutants in the water.

《牛津词典》