Trial Manufacture of Computer-Controlled NMR Spectrometer for NMR of Ferromagnetic Materials in a Wide Frequency Range between 10-1000MHz.

试制计算机控制核磁共振波谱仪，用于10-1000MHz宽频率范围的铁磁材料核磁共振。

• 批准号: 07554011
• 负责人: KASAMATSU Yoshitaka
• 金额: $ 1.22万
• 依托单位: Kure National College of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07554011/
• 关键词: NMR spectrometer; ferromagnetic materials; wide range; automatic measurement; coherent

It is rather difficult to automatize a swept frequency-type spectrometer for measuring the NMR in ferromagnetic materials, because the tuning and matching of the measuring system at each frequency of interest are needed, which consumes time extremely. This is different from the case of a swept field-type NMR spectrometer for paramagnetic materials, which can be easily automatized only by sweeping the applied magnetic field at a fixed frequency. The purpose of this project is to assemble a computer-controlled NMR spectrometer for ferromagnetic materials by using wide band amplifiers and other compornents on the market.The process of assembling a new NMR spectometer was as follows.(1) A self-made NMR spectrometer of the tuned type was rebuilt to work in a wide frequency range between 10 and 1000MHz by using an untuned type of the sample circuit and wide band compornents. Relay circuits were assembled, which control automatically the 180ﾟ phase of the first pulse and the 90ﾟ phase of refe … More rence signal for a double balance mixer.(2) A computer program was made, which controlls a signal generator and a digital oscilloscope.(3) The assembled system was ajusted in such a way that sensitivity for detecting NMR signals is as equal as possible through the whole frequency range.The computer-controlled NMR spectrometer successfully operates for measuring the NMR of ferromagnetic Gd compounds and transsition metal compounds. The measure-ments can be continued automatically over a wide frequency range 10-1000MHz even night and day, if necesary.In our new system there are a few problems to be improved. For example, the sensitivity is a little lower in the frequency range above 500 MHz, and a saturation of the amplifier takes place at some special frequencies owing to mismatch of the impedance at the connecting points of various components in the circuit. These will be improved by using a wide amplifier with high gain in the frequency range above 500 MHz and a aweep generator with high quality in near future. Less

扫频式光谱仪用于铁磁材料核磁共振测量的自动化是相当困难的，因为需要在每个感兴趣的频率下对测量系统进行调谐和匹配，这非常耗时。这与顺磁性材料的扫场型核磁共振波谱仪的情况不同，后者只需以固定频率扫描施加的磁场即可轻松实现自动化。本项目的目的是利用市场上的宽带放大器和其他元件组装一台计算机控制的铁磁材料核磁共振波谱仪。组装新型核磁共振波谱仪的过程如下。(1)利用未调谐型的样品电路和宽带，改造自制的调谐型核磁共振波谱仪，使其工作在10至1000MHz的宽频率范围内。 组件。组装了继电器电路，自动控制双平衡混频器的第一个脉冲的 180° 相位和参考信号的 90° 相位。(2) 编写了计算机程序，控制信号发生器和数字示波器。(3) 调整组装的系统，使检测 NMR 信号的灵敏度在整个频率范围内尽可能相等。 计算机控制的核磁共振波谱仪成功用于测量铁磁 Gd 化合物和过渡金属化合物的核磁共振。如有必要，测量可以在 10-1000MHz 的宽频率范围内自动连续进行，甚至可以在白天和黑夜进行。 在我们的新系统中，有一些问题需要改进。例如，在500MHz以上的频率范围内，灵敏度稍低，在某些特殊频率下，由于电路中各元件连接点的阻抗不匹配，放大器会出现饱和。在不久的将来，这些问题将通过使用在 500 MHz 以上频率范围内具有高增益的宽放大器和高质量的扫频发生器来改善。较少的

项目成果

K.H.J.Buschow,G.R.Grechnev,Anders Hjelm,Y.Kasamatsu,A.S.Panfilov,I.V.Svechkarev: "Exchange coupling in GdM compunds" Journal of Alloys and Compounds. 244. 113-120 (1996)

K.H.J.Buschow、G.R.Grechnev、Anders Hjelm、Y.Kasamatsu、A.S.Panfilov、I.V.Svechkarev：“GdM 化合物中的交换耦合”合金与化合物杂志。

K.H.J.Buschow,G.R.Grechnev,Anders Hjelm Y.Kasamatsu,A.S.Panfilov,I.V.Svechkarev: "Exchange coupling in GdM compounds" Journal of Alloys and Compounds. 244. 113-120 (1996)

K.H.J.Buschow、G.R.Grechnev、Anders Hjelm Y.Kasamatsu、A.S.Panfilov、I.V.Svechkarev：“GdM 化合物中的交换耦合”合金与化合物杂志。

K.H.J.Buschow, G.E.Grechnev Anders Hjelm, Y.Kasamatsu A.S.Panfilov, I.V.Svechkarev: "Exchange coupling in GdM compounds" Journal of Alloys and Compounds. 244. 113-120 (1966)

K.H.J.Buschow、G.E.Grechnev Anders Hjelm、Y.Kasamatsu A.S.Panfilov、I.V.Svechkarev：“GdM 化合物中的交换耦合”合金与化合物杂志。