CN109725050A - A kind of magnetic induction measurement topological structure with Diamagnetic loop - Google Patents
A kind of magnetic induction measurement topological structure with Diamagnetic loop Download PDFInfo
- Publication number
- CN109725050A CN109725050A CN201811534280.9A CN201811534280A CN109725050A CN 109725050 A CN109725050 A CN 109725050A CN 201811534280 A CN201811534280 A CN 201811534280A CN 109725050 A CN109725050 A CN 109725050A
- Authority
- CN
- China
- Prior art keywords
- coil
- inverse
- excitation
- receiving
- receiving coil
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Abstract
The present invention discloses a kind of magnetic induction measurement topological structure with Diamagnetic loop, inverse coil including excitation coil, receiving coil and one with receiving coil coaxial placement, this is passed through the electric current contrary with excitation coil against coil, to generate the excitation field opposite with master drive magnetic field.The inverse coil that the present invention passes through excitation coil, receiving coil and one and receiving coil coaxial placement, the magnetic induction measurement system constituted in this way, it may be implemented to reduce basis signal in the influence of receiving end, and it, will not undue weakening response signal while improving detection system sensitivity uniformity.
Description
Technical field
The present invention relates to magnetic induction measurement technical fields, more particularly to a kind of magnetic induction measurement topology with Diamagnetic loop
Structure.
Background technique
Since biological tissue has weak inductive, the various organs and tissue of human body can also use MIT
(Magnetic Induction Tomography, MIT) is imaged.In addition, the penetrability in magnetic field is very strong, can not only penetrate
General biological tissue, or even can also penetrate the very poor substance of this kind of electric conductivity of skull.Therefore, conduction is used compared to EIT etc.
The detection method of electric current, MIT is as a kind of contactless, not damaged, inexpensive imaging mode, using high frequency low-intensity magnetic field as matchmaker
It is situated between and carries out the detection of conductivity and dielectric constant to object.These characteristics can also make the most of the advantage in article safety check.
But the problem of existing MIT technology and experimental system generally existing some general character, such as in traditional twin coil
In mode configuration can there is imaging resolutions it is not high enough, basis signal is too strong, and the low error of sensitivity is big the problems such as.Wherein most by
Studied personnel's concern be then survey object signal be excited exciting field influence it is excessive because the presence of this problem can generate very
More additivity problem, so that imaging effect is worse.Since the signal strength that testee generates depends on the strong of excitation field
Degree causes detection signal weaker so excitation field intensity is not high.In this situation, the intensity of excitation field is remote on receiving coil
The magnetic field strength generated much larger than vortex.This causes precise measurement signal to become extremely difficult.
In addition, improved magnetic induction measurement system uses the principle of gradient former mostly, the signal measured is not that object produces
Raw magnetic field itself, but its spatial gradient.This is greatly lowered system detection sensitivity, and for the excitation on coil
Magnetic field is cancelled out each other, and system receiving terminal needs complicated zeroing circuit.
Summary of the invention
In view of the technical drawbacks of the prior art, it is an object of the present invention to provide a kind of magnetic strengths with Diamagnetic loop
Topological structure should be detected, it is intended to reduce basis signal in the influence of receiving end and improve the same of detection system sensitivity uniformity
When, it will not undue weakening response signal.
The technical solution adopted to achieve the purpose of the present invention is:
A kind of magnetic induction measurement topological structure with Diamagnetic loop, including excitation coil, receiving coil and one and reception
The inverse coil of coil coaxial placement, this is passed through the electric current contrary with excitation coil against coil, to generate and master drive magnetic
The opposite excitation field in field.
The inverse coil is located at the outside of the receiving coil.
The inverse coil is located at the inside of the receiving coil.
Compared with prior art, the beneficial effects of the present invention are:
The present invention passes through excitation coil, receiving coil and an inverse coil with receiving coil coaxial placement, such institute's structure
At magnetic induction measurement system, may be implemented reduce basis signal receiving end influence, and improve detection system it is sensitive
It, will not undue weakening response signal while spending uniformity.
Detailed description of the invention
Fig. 1 is the structural schematic diagram of the magnetic induction measurement topology with Diamagnetic loop；
Fig. 2 show receiving coil and excitation coil by the waveform diagram after zeroing process；
Fig. 3 is shown using saturated salt solution as when testee, the waveform diagram of receiving coil and excitation coil；
Fig. 4 show the relationship of brine strength Yu signal imaginary part；
Fig. 5 show in the case of three kinds the axially opposing signal response curve figure when radial coordinate is zero；
It is respectively traditional twin coil and the axially opposing letter with inverse loop construction when radial coordinate is 0 shown in Fig. 6 A-6C
Number response diagram；
Magnetic potential equipotential lines and magnetic flux mould when being respectively shown in Fig. 7 A-7B when not opening inverse coil and opening inverse coil
Distribution map；
Fig. 8 show axial signal response distribution map；
Fig. 9 show structure chart when inverse coil radius is greater than receiving coil radius.
Specific embodiment
The present invention is described in further detail below in conjunction with the drawings and specific embodiments.It should be appreciated that described herein
Specific embodiment be only used to explain the present invention, be not intended to limit the present invention.
As shown in Figure 1, the magnetic induction measurement topological structure of the invention with Diamagnetic loop, including excitation coil 10, reception
The inverse coil (30,31) of coil 20 and one and receiving coil coaxial placement.
Fig. 1 gives two kinds of inverse coils, and it to be to set one is setting that one is the inverse coils 30 for the inside for being located at receiving coil
Inverse coil 31 in the inside of receiving coil carrys out principle of specification so that inverse coil is placed on outside receiving coil as an example below, referring to Fig. 9
It is shown.When system needs to carry out test job, apply the AC sine signal of certain frequency and amplitude to excitation coil 10, and
Apply on inverse coil 30 and differ 180 ° of homogenous frequency signal with excitation coil, at this moment two hot-wire coils are by sky between them
Between the magnetic field of superposition is induced in range.
Since the signal phase difference of two coils is about 180 °, by adjusting the range value and fine tuning phase of inverse coil,
So that two coils can be offset in the magnetic field that central space range generates according to certain rule.Therefore, when detection zone does not have
When having test object 100, the case where magnetic flux density is zero can produce receiving end position, it just can be to avoid above-described
The situation that gradient former is introduced in conventional method, can make measurement object become magnetic field itself from magnetic field gradient.
According to the magnetic field strength formula of each coil in space:
Can calculate each coil in detection zone any position (r, z) magnetic density.Assuming that excitation coil
Magnetic density is Bin(r, z), the magnetic density for adding inverse coil is Bout(r,z).By Bin(r,z)-Bout(r, z)=0 can
To calculate the position (r in Zero flux metric density area0,z0).Know that the magnetic density in z-axis is respectively by formula (2)；
Again by Bin(r,z)-Bout(r, z)=0 is available
By formula (5) it is found that the line footpath R for passing through the concentric double excitation coil of settinginAnd RoutAnd electric current IinAnd Iout, i.e.,
It can determine the position in Zero flux metric density area.It can be realized by changing the size against coil reverse current in receiving coil position
The Zero flux density set.In actual circuit, can be returned to zero method using iteration, and the voltage of receiving coil is made to approach zero step by step
Value, the benefit of this method is simple and reliable, and is convenient for write-in program, can give entire cumbersome zeroing process to computer
To realize.
Fig. 2 is the waveform diagram of receiving coil and excitation coil after by zeroing process.
After by above-mentioned zeroing process, the voltage of receiving end becomes very little, and almost and noise is at the same level, then at this time just
It can use the loop construction to measure.When applying the alternating signal of certain frequency on coil, you is cut down according to Biot's Sa
Law (formula 6) will induce corresponding high frequency magnetic field (primary magnetic field) at coil both ends, and testee is in such height
In frequency magnetic field, induced current can produce, then generate alternating magnetic field (secondary magnetic) again.In primary magnetic field and secondary magnetic
Under comprehensive function, the induced electromotive force of generation can detecte on receiving coil using measuring device, and according to electricity of inducting
The features such as such as amplitude, phase of kinetic potential, assesses the tested part of object.
Due to close with tissue conductive characteristic, we will use saline solution to inquire into feasibility of the invention.Saturation is eaten
Salt water is placed in two coil middle positions, then can on oscillograph under the conditions of 1MHz signal frequency as test sample
To obtain a new waveform, as shown in Figure 3.
Fig. 3 is using saturated salt solution as when testee, the waveform diagram of receiving coil and excitation coil.
Under high frequency magnetic field, influence of the dielectric constant of salt water to its conductivity measurement is very big:
I.e. the imaginary part of signal could reflect the electric conductivity of salt water.In order to calculate the imaginary part for obtaining signal, need to measure simultaneously
Receive the amplitude and phase of signal.Using the amplitude and phase detection function of oscillograph, amplitude and phase information can be obtained, and
The imaginary part of signal is calculated.As shown in figure 4, the imaginary values of signal are also increase accordingly, salt water with the increase of brine strength
Concentration and the imaginary values of signal correspond, the magnetic induction topological structure with counter field coil that experimental verification is introduced herein
Feasibility.
In the present invention, this is against coil and receiving coil concentric co-axial, against coil radius R2, it is greater than receiving coil radius R3, and
It is passed through the electric current contrary with excitation coil, to generate the excitation field (i.e. counter field) opposite with master drive magnetic field.It should
Inverse coil system has the advantages that with next: offsetting the excitation field effect of signals on receiving coil, in turn avoids simultaneously
The case where reducing excitation field intensity like that in M.Heidary Dastjerdi method appearance.
The result emulated in MATLAB R2016a software below as an example, is believed qualitatively to illustrate that the present invention is axial
Number response condition.Have no loss of generality, set in this example: excitation coil radius is R1=40mm, inverse coil radius R2=200mm is received
Coil radius is R3=40mm, receiving coil and excitation coil space D=200mm, receiving coil and inverse coil concentric co-axial are put
It sets.If it is 1A that pumping signal, which generates electric current, value of the magnetic responsiveness in axially distinct position when calculating radial coordinate is zero.Utilize public affairs
Formula (4) (5) is calculated when making receiving end magnetic flux density be zero or ignore, and the size of required reverse current is
0.011543A.Similarly, inverse coil position is calculated in two kinds of situations at excitation end with such method, current value is
0.067629A.It can be seen that the present invention can about be reduced to original 1/6 compared to for inverse coil is added at excitation end.In reality
Application in, due to higher to magnetic field requirements, so electric current may be very big.
The present invention also uses relative signal response reflection receiving end signal situation of change, it is assumed that test macro itself is not led
Electricity, and the electric conductivity of testee is sufficiently large, is calculated by excitation field and the dot product of receiving end inducting flux metric density opposite
Signal response.
Since the topological structure that the present invention is previously mentioned is axisymmetric, and as imaging unit, generally require a large amount of
Unit is arranged into array to be probed into, and size is much smaller compared to testee, therefore compares axial resolution, and radial point
Resolution seems less very important, therefore probes into response distribution problem in the axial direction in this emphasis.
Excitation coil (R is calculated separately out according to formula (4) (5) first in MATLAB1), inverse coil (R2) and reception line
Enclose (R3) each comfortable radial coordinate be 0 axis on the magnetic field strength of each point (respectively correspond B1,B2,B3), then calculated by dot product
Obtain relative signal response.Due to having factor mu in formula0IoutIin, and we are only concerned last product and several moulds
Relative response intensity between formula, therefore k=might as well be setTake k1=1, k3=1.It can be calculated according to formula (4)
Corresponding k when magnetic field strength is zero at receiving coil2Value.
Every bit in the z-axis relative response intensity under twin coil mode are as follows:
Every bit in the z-axis relative response intensity under twin coil mode are as follows:
Fig. 5 illustrates the axial response curve in the case of three kinds.Wherein A curve shows traditional twin coil mode, can
To see that response intensity difference of the A curve middle position with two sides close to reception and excitation coil position is very big, that is to say, that go out
The now nonuniform response distribution of " two sides are strong, intermediate weak "；B curve shows discussed herein, i.e., is added in inverse coil and connects
The case where receiving end；C curve shows the case where when motivating end that inverse coil is added.Wherein abscissa is axial length, left
While arising from as excitation coil, receiving coil is terminated at, unit is millimeter, and ordinate is relative signal response.
In order to more preferably observe the axially opposing signal response of magnetic induction topological structure and probe into its uniformity, scheme
6A-6C respectively illustrates the axially opposing signal response diagram for each case for being utilized respectively that MATLAB makes.Wish obtained
Signal is that uniformly, i.e., the response generated in different positions should obtain within the scope of one smaller as far as possible.?
In Fig. 6 A, it can be seen that many times strong by the response relative intermediate position of two close end coil position under traditional twin coil mode.
If the lower limit of our specified signal fluctuation ranges cannot be less than the 50% of the range limit signal, it may be seen that figure
Meet the siding-to-siding block length required in this way up to 154mm in 6A, similarly according to Fig. 6 B and Fig. 6 C it is available they meet the requirements
Longest section be respectively 169mm and 211mm.
Fig. 6 A-6C shows traditional twin coil and rings with axially opposing signal of the inverse loop construction when radial coordinate is 0
Ying Tu, according to Fig. 6 A-6C, and as the above analysis, inverse coil can obtain maximum area at receiving end in these three modes
Between, that is to say, that such scheme weakens part and crosses the signal of strong signal, especially receiving end, to be achieved more
Reasonable even results；When inverse coil is added in excitation end, inverse coil also results in while weakening magnetic field near receiving coil
Excitation end and middle section response signal it is weak significantly weakened so that system responds after 100mm, and swash
Encouraging end but has biggish response signal, therefore this laying method weakens response substantially, and not as good as proposed in this paper
Scheme can more obtain preferable axial uniformity.
To sum up, compared with traditional twin coil magnetic induction topological structure, the magnetic induction topological structure that band adds reverse coil exists
The magnetic flux density close to zero can occur in detection zone, to avoid directly being examined using magnetic field as object using gradient former
It surveys；In addition, the position of inverse coil is placed in receiving end, the sound that response homogeneity can also keep relatively high not only can be improved
Intensity is answered, while also reducing the size of the reverse signal amplitude on inverse coil.
The following figure is to be to the magnetic density at receiving coil that can make proposed in scheme using COMSOL simulation software
Zero feasibility is verified and has been illustrated.Related data is arranged to the description that each coil carries out according in technical solution.By
It calculates and draws, be the magnetic potential equipotential lines and magnetic flux mould distribution map in the case of two kinds shown in Fig. 7 A-7B, wherein the exhibition of left side institute
What is shown is twin coil mode magnetic field distribution map when not opening inverse coil, and right side is magnetic field when applying reverse signal to inverse coil
Distribution map.It can be seen that from Fig. 7 A-7B in the case where not opening inverse coil, the magnetic flux of receiving coil position still exists,
And inverse coil can then make the magnetic flux on receiving coil close to zero after being added, so that the induced electricity on receiving coil be made to crimp
Nearly zero.
Due to the magnetic field symmetry with higher that circular coil induces, excitation coil in experiment receives line
Circle and inverse coil are all coaxial placements.It can be seen that receiving coil position is implicitly present in the very small point of magnetic flux density.Thus
Illustrate, by adjusting the electric current of main coil and inverse coil, the magnetic flux on receiving coil can be made close to zero, to make to receive
Induced voltage on coil is zero.
For the inverse coil of different radii, the axial response distribution map of system is made using MATLAB, as shown in Figure 8.Its
Middle curve A is the two coil configuration that radius is R1=R3=40mm；On this basis, the corresponding inverse coil radius of curve B1 is
R21=30mm, inverse coil are located in receiving coil；The corresponding inverse coil R22=35mm of curve B2, inverse coil are located at receiving coil
It is interior；Curve C corresponding inverse coil R2=200mm, receiving coil R3=40mm, inverse coil are located at except receiving coil.
When the radius of inverse coil is less than receiving coil radius, inverse coil is in inside receiving coil, at this time in satisfaction
The magnetic responsiveness in the smaller range of receiving end will be reduced by stating the inverse coil after zeroing requires, and with inverse coil half
The increase of diameter, the signal response close to receiving end are reducing；And when the radius of inverse coil is greater than receiving coil radius, inverse coil
The previous case will be compared, the radius of inverse coil becomes larger, is unfavorable in the outside of receiving coil, after reaching zeroing result
Miniaturization processing, it is important that the response distribution in measurement space will be more uniform, as shown in Fig. 8 curve C.Therefore, exist
Preferentially selection is greater than the inverse coil of receiving coil radius in the present invention.
According to previously discussed as a result, be implicitly present in the very small point of magnetic flux density in the position of receiving coil, work as main line
When circle and inverse coil all use voltage source excitation, their phase difference should be made to be kept for 180 °, but the inductance of the two with exchange
Resistance is all not necessarily the same, and along with the mutual inductance of two coils influences, leading to the phase difference of coil current may not be 180 °.?
In COMSOL magnetic field simulation, by calculating the impedance of two coils, and the phase difference of the two is calculated, is shown in Table 1:
Table 1
It can be seen that phase difference has a degree of floating within 1 °, phase difference can be found smaller closer to 180 °
Magnetic flux.
The skin effect depth of strong conductive object is smaller, causes to be difficult to detect the part deeper apart from surface, this
Outside since strong conductive object has apparent inductance characteristic, this will will cause vortex hysteresis, so strong conductive in detection
Property object make it should be noted that vortex hysteresis cause receiving coil occur delayed phase.It therefore, should in actual experiment
Notice that the electrology characteristic bring of object to be detected influences.
The premise that the present invention realizes is the interference without other magnetic fields, and in actual operation, due to electronic equipment, it is powered and leads
The presence of line and human biological electricity etc., will make the receiving coil of detection device by different degrees of interference, therefore
Adequate shielding measure must be taken in when practical operation, impacted to avoid these outer bound pair measurement results
The above is only a preferred embodiment of the present invention, it is noted that for the common skill of the art
For art personnel, various improvements and modifications may be made without departing from the principle of the present invention, these improvements and modifications
Also it should be regarded as protection scope of the present invention.
Claims (3)
1. a kind of magnetic induction measurement topological structure with Diamagnetic loop, which is characterized in that including excitation coil, receiving coil and one
A inverse coil with receiving coil coaxial placement, this is passed through the electric current contrary with excitation coil against coil, thus generate and
The opposite excitation field in master drive magnetic field.
2. the magnetic induction measurement topological structure with Diamagnetic loop as described in claim 1, which is characterized in that the inverse coil is located at
The outside of the receiving coil.
3. the magnetic induction measurement topological structure with Diamagnetic loop as described in claim 1, which is characterized in that the inverse coil is located at
The inside of the receiving coil.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811534280.9A CN109725050A (en) | 2018-12-14 | 2018-12-14 | A kind of magnetic induction measurement topological structure with Diamagnetic loop |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811534280.9A CN109725050A (en) | 2018-12-14 | 2018-12-14 | A kind of magnetic induction measurement topological structure with Diamagnetic loop |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN109725050A true CN109725050A (en) | 2019-05-07 |
Family
ID=66295982
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811534280.9A Pending CN109725050A (en) | 2018-12-14 | 2018-12-14 | A kind of magnetic induction measurement topological structure with Diamagnetic loop |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109725050A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111007113A (en) * | 2019-11-22 | 2020-04-14 | 湖南城市学院 | Optimized design method for metal oxide semiconductor gas sensor structure |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4255711A (en) * | 1979-05-15 | 1981-03-10 | Compass Electronics Corporation | Coil arrangement for search head of a metal detector |
| US5793199A (en) * | 1995-11-10 | 1998-08-11 | New Cosmos Electric Co., Ltd. | Method and apparatus for determining magnetic powder concentration by using the electromagnetic induction method |
| WO2012140265A2 (en) * | 2011-04-15 | 2012-10-18 | Icontrols, K.S. | Apparatus and method for detecting electrically conductive items |
| CN105891057A (en) * | 2016-05-12 | 2016-08-24 | 绍兴文理学院 | Double-excitation solenoid type particle sensitive detection device adopting full-band filtering |
-
2018
- 2018-12-14 CN CN201811534280.9A patent/CN109725050A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4255711A (en) * | 1979-05-15 | 1981-03-10 | Compass Electronics Corporation | Coil arrangement for search head of a metal detector |
| US5793199A (en) * | 1995-11-10 | 1998-08-11 | New Cosmos Electric Co., Ltd. | Method and apparatus for determining magnetic powder concentration by using the electromagnetic induction method |
| WO2012140265A2 (en) * | 2011-04-15 | 2012-10-18 | Icontrols, K.S. | Apparatus and method for detecting electrically conductive items |
| CN105891057A (en) * | 2016-05-12 | 2016-08-24 | 绍兴文理学院 | Double-excitation solenoid type particle sensitive detection device adopting full-band filtering |
Non-Patent Citations (1)
| Title |
|---|
| MARAL HEIDARY DASTJERDI ET AL.: "Induktionsfelder mit vorteilhaften Topologien in der Magnetischen-Induktions-Tomografie", 《TM-TECHNISCHES MESSEN》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111007113A (en) * | 2019-11-22 | 2020-04-14 | 湖南城市学院 | Optimized design method for metal oxide semiconductor gas sensor structure |
| CN111007113B (en) * | 2019-11-22 | 2020-09-01 | 湖南城市学院 | Optimized design method for metal oxide semiconductor gas sensor structure |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US20120019238A1 (en) | Magnetic induction tomography systems with coil configuration | |
| US20060125475A1 (en) | Radio frequency impedance mapping | |
| US3764897A (en) | Electromagnetic thickness gauging using a transmitting coil shaped to provide a constant field over a range of measuring distances | |
| Scharfetter et al. | A new type of gradiometer for the receiving circuit of magnetic induction tomography (MIT) | |
| CN1006359B (en) | Method of generating motion signal and mri tomography apparatus for performing such a method | |
| US11221380B2 (en) | Method and apparatus for analyzing a sample volume comprising magnetic particles | |
| RU2367982C1 (en) | Method of logging with application of nuclear-magnetic resonance and device for its realisation | |
| JPH0349454B2 (en) | ||
| Giovannetti | Comparison between circular and square loops for low‐frequency magnetic resonance applications: theoretical performance estimation | |
| Attaran et al. | Reliable RF B/E-field probes for time-domain monitoring of EM exposure during medical device testing | |
| US10473736B2 (en) | Subject-loaded helical-antenna radio-frequency coil for magnetic resonance imaging | |
| Vít et al. | A broad tuneable birdcage coil for mouse 1H/19F MR applications | |
| CN109725050A (en) | A kind of magnetic induction measurement topological structure with Diamagnetic loop | |
| Gençer et al. | Forward problem solution for electrical conductivity imaging via contactless measurements | |
| Stawicki et al. | A new transducer for magnetic induction tomography | |
| Morin et al. | An Optimized 2 MHz Unilateral Magnet with a Large Homogeneous Sensitive Spot | |
| CN101563027A (en) | Method and arrangement for locating magnetic markers in a region of action | |
| Xu et al. | Design and Testing of a Multi-Channel 1H/3He Double-Nuclear Transmit Coil Array for Magnetic Resonance Imaging at an Ultra-Low Field | |
| Thiyagarajan et al. | Design and analysis of microstrip-based RF birdcage coil for 1.5 T magnetic resonance imaging | |
| CN117547242B (en) | Magnetic induction tomography apparatus | |
| Frijia et al. | Design, simulation, and test of surface and volume radio frequency coils for 13C magnetic resonance imaging and spectroscopy | |
| Liu et al. | Method for improving accurate measurement of the magnetic field of wireless passive micro-magnetic stimulator micro-coil | |
| CN108802640A (en) | Coil device for emitting high frequency radiation | |
| Xu et al. | Modeling and Analysis of Litz Wire Radiofrequency (RF) Coil in Inside-Out NMR Well Logging Sensor | |
| Bayazitov et al. | A Receiving Coil for a Specialized Compact Magnetic Resonance Imaging System |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20190507 |
|
| WD01 | Invention patent application deemed withdrawn after publication |