The UK-based Royal Commission on Environmental Pollution says that while the materials have so far shown no sign of being harmful, there is a "major gap" in research about their potential risks.

这份报告由英国皇家环境污染委员会完成，它说，尽管纳米材料迄今为止没有表明有害的迹象，但是对其潜在风险的研究还有“严重的欠缺”。

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This book fills a major gap in lexicography .

这本书填补了词典学方面的重大缺门。

youdao

Adoption would fill in a major gap in the regulatory regime for derivatives.

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This level represents the bottom of the major gap lower CMG experienced early in the second half of July, a gap down that took shares of Chipotle Mexican Grill from bull market territory to bear market territory overnight.

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However, major US firms including Gap Inc, Walmart and Sears have said they will not sign the agreement, throwing its impact into question.

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