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超声波及其应用

人耳最高只能感觉到大约20000Hz的声波,频率更高的声波就是超声波了.超声波具有许多奇异特性:空化效应﹣﹣超声波能在水中产生气泡,气泡爆破时释放出高能量,产生强冲击力的微小水柱,它不断冲击物体的表面,使物体表面及缝隙中的污垢迅速剥落,从而达到净化物体表面的目的.传播特性﹣﹣它的波长短,在均匀介质中能够定向直线传播,根据这一特性可以进行超声探伤、测厚、测距、医学诊断等.

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    China's cancer researcher Zhu Chen, together with two French researchers Anne Dejean and Hugues de Thé, received Sjoberg Prize 2018 in Stockholm Concert Hall, Sweden on Friday.

    “We used wisdom from both Chinese and Western medicine and offered a cure to one of the most deadly cancers,” Chen told Xinhua, “I feel that Chinese medicine has potential to contribute more to human health. It struggles for benefiting all mankind. It's a language of peace, and of development and progress.” Chen recalled the cooperation with the two French researchers for over 30 years.

    This year's Sjoberg winners have developed a new and targeted treatment for a specific form of blood cancer called acute promyelocytic leukaemia (急性早幼粒白血病). It was once one of the deadliest forms of cancer, but it is now possible to cure nine out of ten patients who receive the new treatment. The winners have made this revolutionary development possible by methodically mapping the molecular mechanisms responsible for the disease.

    The Prize is awarded by the Royal Swedish Academy of Sciences and is funded (资助)by the Sjoberg Foundation. The foundation, with a donation of 2.5 billion US dollars, was founded in 2016, and serves to promote scientific research that focuses on cancer, health and the environment.

    The Prize is an annual international prize in cancer research awarded to individual researchers or research groups. The prize amounts to one million US dollars, of which 100,000US dollars is the prize sum and 900,000US dollars is funding for future research.