SU552551A1

SU552551A1 - Method for measuring relaxation time of a fluid

Info

Publication number: SU552551A1
Application number: SU2125821A
Authority: SU
Inventors: Александр Иванович Жерновой; Владимир Михайлович Леонов
Original assignee: Ленинградский Ордена Трудового Красного Знамени Технологический Институт Им. Ленсовета
Priority date: 1975-04-18
Filing date: 1975-04-18
Publication date: 1977-03-30

Description

1one

Способ предназначаетс дл определение концентрации парамагнитных ионов и свободных радикалов в растворах и может найти применение в химии, радиохимии, электрохимии , гальванических производствах, электрометаллургии .The method is intended to determine the concentration of paramagnetic ions and free radicals in solutions and can be used in chemistry, radiochemistry, electrochemistry, electroplating, and electrometallurgy.

Известен способ измерени времени релаксации на основе дерного магнитного резонанса (ЯМР), включающий операции инверсии дерной намагниченности и регистрации сигнала ЯМР при наличии и отсутствии инверсии . Однако известный способ не позвол ет проводить измерени времени релаксации без отбора проб непосредственно в технологическом процессе.There is a method for measuring nuclear magnetic resonance (NMR) relaxation time, which includes the operations of nuclear magnetization inversion and recording of the NMR signal in the presence and absence of inversion. However, the known method does not allow measurements of the relaxation time without sampling directly in the process.

Наиболее близким техническим решением., (прототипом) вл етс способ измерени времени релаксации (Т) жидкости путем ее пол ризации сильным магнитным полем, пропускани по двум каналам разного объема и последующей регистрации амплитуд сигналов ЯМР. Его недостатком вл етс необходимость переключени каналов. Переключение каналов трудно автоматизировать; кроме того , при переключении неизбежен гидравлический удар, в результате которого мен етс настройка устройства дл регистрации сигнала А, что приводит к понижению точности измерений .The closest technical solution. (Prototype) is a method for measuring the relaxation time (T) of a liquid by polarizing it with a strong magnetic field, passing different volumes through two channels and then recording the amplitudes of the NMR signals. Its disadvantage is the need to switch channels. Channel switching is difficult to automate; In addition, a hydraulic shock is inevitable when switching, as a result of which the setting of the device for recording the signal A changes, which leads to a decrease in measurement accuracy.

Целью изобретени вл етс автоматизаци и повышение точности измерений.The aim of the invention is to automate and improve measurement accuracy.

Поставленна цель достигаетс тем, что жидкость пропускают по двум каналам одновременно , в одном изканалов производ тинверсию дерной намагниченности и регистрируют амплитуду сигнала ЯМР при наличии и при отсутствии инверсии.The goal is achieved by the fact that the fluid is passed through two channels simultaneously, in one of the channels, a nuclear magnetization is inverted and the amplitude of the NMR signal is recorded with and without inversion.

Схема устройства дл измерени времени релаксации предлагаемым способом приведена на чертеже.A diagram of a device for measuring the relaxation time by the proposed method is shown in the drawing.

Оно содержит пол ризатор 1, катущку 2 и схему 3 дл регистрации сигнала ЯМР, каналы 4, 5 дл протекани жидкости, катушку 6 дл инверсии намагниченности, присоединенную к генератору 7.It contains a polarizer 1, a coil 2 and a circuit 3 for recording the NMR signal, channels 4, 5 for the flow of fluid, a coil 6 for inverting the magnetization connected to the generator 7.

Устройство работает следующим образом.The device works as follows.

Протека по объему пол ризатора 1 жидкость пол ризуетс , то есть в ней возникает дерна намагниченность MQ, при протекании жидкости по каналам 4 и 5, расположенным в слабом магнитном поле, дерна намагниченность уменьшаетс . На выходе канала 4 намагниченность равнаThe flow through the volume of polarizer 1 liquid is polarized, i.e. the MQ magnetization arises in it, when the fluid flows through channels 4 and 5 located in a weak magnetic field, the sod magnetization decreases. At the output of channel 4, the magnetization is equal to

М - , на выходе канала 5 намагниченность равнаM -, at the output of channel 5, the magnetization is equal to

Claims

M, where, is the volume of channels 4 and 5, q is the fluid flow rate, TI is the relaxation time. If the fluid flow rates in channels 4 and 5 are the same, then liquid 2 with nuclear magnetization / I ZL MO -qT, –PHT –– I 22 22 V is applied to coil 2 This magnitude is proportional to the signal amplitude, NMR AI at the output of circuit 3. If using the generator 7 in the coil 6 creates a resonant alternating field producing the inversion of the nuclear magnetization in channel 5, then at the output of channel 5 the magnetization Ml, V, lqT, and the average magnetization in the coil 2: y, Ji M + MS (, -cht. This value is proportional to the amplitude of the NMR signal AZ, obtained at the output of circuit 3 in the presence of inversion coiling in the coil 6. Measuring the amplitudes of the signal AI (without inversion of magnetization) and AZ (if there is iversion of magnetization), one can determine the relaxation time using the formula: where AU is the difference between the volumes of channels 5 and 4. An induction magnet was used as polarizer 1. 0.5 t, as the circuit 3, the serial device E11-2, as the generator 7, the device GZ-33. The signal from the output of the synchronous detector of the circuit 3 was recorded with a self-testing voltmeter EPP-09. The method provided a measurement of TI with a relative error of about 2%, which is 2.5 times less than the error provided by the prototype. The method makes it possible to automate measurements by periodically turning on and off the generator 7. Formula of the invention A method for measuring the relaxation time of a liquid by polarizing it with a strong magnetic field, passing a different volume through two channels and then recording the amplitudes of the NMR signals, characterized by increase the accuracy of measurements, the fluid is passed through two channels simultaneously, in one of the channels an inversion of the nuclear magnetization is performed and the amplitude of the NM signal is recorded with and without inversion.