Yet Bourbaki's project yielded unexpected consequences. Their terminology and style didn't naturally suit all mathematical varieties. For instance, combinatorics (frequently described as enumeration science) and graph theory (network science) tend toward concreteness and visualization. Consequently, for decades they remained marginalized at premier American and European institutions; they flourished only where Bourbaki's influence remained limited, like Hungary.
随着技术进步，MRI设备的氦耗已大幅下降。早期MRI设备氦气泄漏速率约每小时0.4升，需要配备1000-2000升的大型储罐，每数月就需补充。（气态氦防泄漏难度极大，这也正是氦气常用于检漏的原因。）但现代MRI设备采用“零蒸发”技术，基本无需补充氦气。随着这些设备市场份额扩大，MRI设备的氦气需求预计将持续下降。但在可预见的未来，MRI仍将是氦气的重要需求来源。
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