After the discovery of EPR by E.K. Zavoiski 1944 in Kazan (E.K. Zavoiski Zhurn Eksperimentalnoi i teoreticheskoi fiziki 15:344, 1945; E.K. Zavoiski J Phys USSR 9:211–245, 1945) EPR spectrometers were home-built and mostly dedicated to a special application. But commercial instruments in the contrary must be universal and cover a broad range of methods and applications. Therefore they should be compatible with any valuable accessory and offer optimal sensitivity and resolution and they should be easily convertible to other frequency bands and new methods of investigation. The sensitivity of the EPR has increased in consecutive steps, from a S/N of 200 for the week pitch in 1970 up to 3000 with a new microwave source and a new super high Q cavity (SHQE). So far all the main requirements for a universal cw-EPR spectrometer for scientific applications have been met successfully. In 1987 with the ESP380 the first commercial pulse EPR spectrometer was introduced. This was no more an improvement of the previous EPR, this was a revolution in EPR instrumentation. Some necessary microwave-components were not available on the market and had to be developed and produced by the company itself. To cope with the extremely short relaxation times, necessitating high bandwidths, a new range of resonators had to be developed. In cooperation with the Eaton-group Bruker has introduced a rapid scan accessory for the ELEXSYS spectrometers increasing sensitivity for almost two orders of magnitude. The rapid scan may also give new possibilities for EPR imaging in the much less sensitive S- and L-bands for biomedical research.

中文翻译：

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EPR 75 年。布鲁克 60 年 EPR 里程碑

在 EK Zavoiski 1944 在喀山发现 EPR 之后（EK Zavoiski Zhurn Eksperimentalnoi i teoreticheskoi fiziki 15:344, 1945; EK Zavoiski J Phys USSR 9:211–245, 1945）EPR 光谱仪主要用于家用专用光谱仪应用。但相反，商业仪器必须是通用的，并涵盖广泛的方法和应用。因此，它们应该与任何有价值的附件兼容，并提供最佳的灵敏度和分辨率，并且它们应该很容易转换到其他频段和新的调查方法。EPR 的灵敏度逐步提高，从 1970 年周音高的 S/N 为 200，使用新的微波源和新的超高 Q 腔 (SHQE) 提高到 3000。到目前为止，已成功满足了用于科学应用的通用 cw-EPR 光谱仪的所有主要要求。1987 年，随着 ESP380 的推出，第一台商用脉冲 EPR 光谱仪问世。这不再是对之前 EPR 的改进，这是 EPR 仪器的一次革命。市场上没有一些必要的微波组件，必须由公司自己开发和生产。为了应对极短的弛豫时间，需要高带宽，必须开发一系列新的谐振器。布鲁克与伊顿集团合作推出了用于 ELEXSYS 光谱仪的快速扫描附件，将灵敏度提高了近两个数量级。