Research website of Vyacheslav Gorchilin
2018-12-17
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Nuclear magnetic resonance of certain materials in the inductor
Another type of resonance is not ceases to amaze the scientific world for over 80 years. His research has already received 4 Nobel prize, based on it created numerous devices spectrometry, it is used in chemical reactions for anomalous emission and absorption of energy, and in medicine this kind of resonance was quite indispensable, because it is the basis of the method of magnetic resonance imaging. We are talking about nuclear magnetic resonance (NMR) [1].
To study NMR in the labs use a fairly strong magnetic field or increasing the variables and the mechanical rotation of the test material. With other methods — mechanics may be lacking, but in return, it is much more complicated the technique and required equipment.
Стенд для исследования ЯМР в катушке индуктивности
Fig.1. Stand for the study of NMR in the inductor
The purpose of this note is to acquaint readers with a fairly simple way to detect NMR from three metals: copper, iron and aluminium, with the help of resonance of the second kind (RVR) and various types of inductors.
We will apply to study the classical scheme of kluchevaya parallel oscillatory circuit (Fig. 1), in which the capacitance C1 is adjusted for resonance frequency, and the inductor L1, more specifically the material of the conductor, and to be explored. The resistance of this coil — R1 does not affect the classical resonance frequency, and for PAP is given by (1.9). It should be noted that the manifestation of NMR the classical resonance is many times less than in RVR, so for experiments we will use only the latter.
The oscillator circuit GG1, you can take one of the following links: generator 1-150 kHz, the generator 10 to 500 kHz (Fig. 4, 5) or use any other material with similar characteristics.
Conductor material of coil: copper
If a conventional inductor wound around a copper wire, put in the classic mode resonance or RVR, the NMR characteristics will be manifested weakly (photo) or do not occur. Therefore, we will use a bifilar winding (Fig. 2.1), which, at the same power consumption of the generator, you can get the big magnetic induction. This statement is not sufficient, because the idea is that you would on a normal coil to create the same induction and get the same result. However, experiments have shown that in experiments of this kind, for the qualitative manifestations of the effects NMR, the type of winding plays a huge role!
Another manifestation of the desired effect is the malfunction of adjacent equipment. Moreover, these phenomena can occur at relatively low capacities, about 3-4W. Even at these low energies, the author completely turned off the computer and hung oscilloscope, which greatly hampered the research process.
Бифилярная катушка из медного провода
Fig.2.1. Bifilar coil of copper wire
Осциллограмма импульсов на медной бифилярной катушке
Fig.2.2. The oscillogram of the pulses on the copper bifilar coil
Осциллограмма одного импульса при последовательно включении обмоток
Fig.2.3. The oscillogram of one pulse sequentially enabling the windings
Осциллограмма одного импульса при параллельном включении обмоток
Fig.2.4. The waveform of one pulse in parallel windings
If a coil (Fig. 2.1) to apply pulses from the generator GG1 and look at the overall waveform (Fig. 2.2), the NMR manifestations of it are poorly marked. But if the waveform to deploy up to one pulse, the effect of NMR is already clearly visible (Fig. 2.3). In this case, the coil windings are connected in series, as in the patent of Tesla [2]. Even more, this effect can be enhanced, if you connect the bifilar winding coil in parallel, then the beats NMR will be even more intense (Fig. 2.4). Perhaps this is due to the greater magnetic induction, but, as previously noticed, it may be insufficient explanation.
Зависимость частоты ЯМР от тока в катушке
Fig.3.1. The dependence of the NMR frequency from the current in the coil
Since the NMR frequency for the nuclei is directly proportional to the dependence on the magnetic field induction [3], that with increasing current in the coil, it will also increase. Recall that in RVR, the phase current is almost equal to the phase voltage. Figure 3.1 shows such a dependency: when the current begins to increase, the frequency of the NMR lowest (f1) and with a maximal current — the greatest (f10).
The wire for the coil used in this experiment, you can take out the audio cable, but the wires in it should be all copper is important. The core diameter — 0.5-1mm, the diameter of the entire coil — 12-13cm. Capacity C1 — 33нФ, and the frequency of the generator GG1 is of the order of 20 kHz. It adapts to the frequency of RVR.
The experiment in this format, in fact, equivalent to the classic, which uses a strong magnetic field increasing and there is a mechanical rotation of the test material.
The material of the conductor coil: aluminum
The coil of this metal coiled in the classical way, also do not show signs of NMR on the waveform. For winding bifilar variant the author used an aluminum construction and adhesive tape, wound it on a Foundation of conductive material (Fig. 4.1).
Бифилярная катушка из алюминиевого провода
Fig.4.1. Bifilar coil of aluminum wire
Осциллограмма импульсов ЯМР на алюминиевой бифилярной катушке
Fig.4.2. The oscillogram of the NMR pulses on aluminum bifilar coil
The oscillator frequency GG1 for RVR in this case was slightly higher, and oscilogram NMR was such, as in figure 4.2.
The material of coil conductor: iron
With the exception of a number of appeared coil wound steel wire (grade PNSW). For the manifestation of effects NMR it is possible to reel in the classical way (Fig. 5.1).
Классическая катушка из стального провода
Fig.5.1. Classic coil of steel wire
Осциллограмма импульсов ЯМР на стальной катушке
Fig.5.2. The oscillogram of pulse NMR on steel coil
Frequency GG1 in this case was much lower than copper and aluminum coils, which corresponds to the theory of NMR.
Insights
As a result of these studies were quite simple method of manifestation of the effects of NMR in the inductors. The best way of winding — bifilar, and if the winding consists of two wires, the best connection is parallel.
From the previous paragraph and some of the side effects NMR in the form of interference to the adjacent equipment, the author makes the assumption that in the process of getting involved a second NMR magnetic field [4], which is just different guidance induced charge on a single conductor. It is also possible that the process NMR is closely associated with a longitudinal wave that is spread along the conductor and depends on such factors: its atomic and domain structure and on the magnetic field in it. In this case, NMR can be called a longitudinally-oriented.
Judging by the oscillograms, the energy NMR higher than is spent on the creation of a magnetic field. But there are energy losses on the active resistance of the inductor, which may offset this effect.