CA2384819A1 - Flow-through probe for nmr spectrometers - Google Patents
Flow-through probe for nmr spectrometers Download PDFInfo
- Publication number
- CA2384819A1 CA2384819A1 CA002384819A CA2384819A CA2384819A1 CA 2384819 A1 CA2384819 A1 CA 2384819A1 CA 002384819 A CA002384819 A CA 002384819A CA 2384819 A CA2384819 A CA 2384819A CA 2384819 A1 CA2384819 A1 CA 2384819A1
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- Prior art keywords
- probe
- portions
- conduit
- chamber
- coil
- Prior art date
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Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
- G01R33/28—Details of apparatus provided for in groups G01R33/44 - G01R33/64
- G01R33/30—Sample handling arrangements, e.g. sample cells, spinning mechanisms
- G01R33/31—Temperature control thereof
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
- G01R33/28—Details of apparatus provided for in groups G01R33/44 - G01R33/64
- G01R33/32—Excitation or detection systems, e.g. using radio frequency signals
- G01R33/34—Constructional details, e.g. resonators, specially adapted to MR
- G01R33/34092—RF coils specially adapted for NMR spectrometers
Abstract
There is disclosed an NMR probe including a body defining an internal chambe r. This chamber is adapted for supporting a vacuum and the body is of a non- magnetic material. A conduit extends through the chamber in the body. The conduit has a first portion in communication with second portions, the first portion being intermediate the second portions, with the first and second portions of non-magnetic materials with substantially equal thermal expansio n coefficients. An RF coil is positioned along at least a substantial portion of the first conduit portion. It is preferred that this device also include a field or frequency lock unit in the chamber, as well as a getter, to allow f or degassing in the chamber to maintain the preferred high pressure vacuum. A method of using this NMR probe for NMR analysis is also disclosed.
Description
,_ 00/,,00558 ~.- 8 ?' Jt~i 2Qat 1 I'~LOW-THROUGH >PROBF FOIL NMR gPE~TRO,~ETERS
3 p'ield of he Inyention 4 The invention is directed to nuclear magnetic resonance (NMR) testing apparatus and in particular to probes for NMR spectrometers.
Bac ~a of the Invention 7 Nuclear magnetic resonance (NMR) testing of substances to determine the constituents 8 therein is well known in the art. In known devices, the sample is arranged between the poles of a 9 magnet and is enclosed by a wire coil to az~able a sample to be subjected to RF electromagnetic pulses of a predetermined frequency. The resulting NMR pulse generated by the nuclei of the 11 sample under test is detected and processed by the NMR device in a well latlown matuier to 12 identify the sample constituents.
13 NMR analysis may be performed in devices commonly lmown as spectrometers.
These 14 spectrometers are designed so as to have a probe, that accepts the sample to be analyzed, between poles of a magnet. The RF coils and tuning circuitry associated with the probe create a 16 field (B), that rotates the net magnetization of the nucleus- These RF
coils also detect the 17 transverse magne~zation as it processes in the X,Y plane. The RF coil pulses the sample nucleus 18 at the Lamer frequency, so as to generate a readable signal for sample identification.
19 An exemplary probe that performs in accordance with that described immediately above ' i0 is disclosed in commonly owned U.S. Patent No. 5,371,464 (Rapoport), and is incorporated by 21 reference herein. This probe, and others like it, while an improvement in the art, still had several 22 disadvantages. ' 23 The gteatest disadvantage involved temperature changes, particularly temperature 24 increases associated with heating the magnet as a result of the strong thermal conductivity 2S between the sample stream and the magnet itself. This is due mainly to samples that must be ntn 26 through the stream at high ten".peraturcs, so as to remain liquid for analysis, and avoid gelling, 27 solidifying or the like, if cooled. These samples typically dissipate within from the probe, that is 28 transferred through air in the ambient environment, ultimately reaching the magnet and raising um uu~~~
~ 7: JUN 2001 1 its temperature. Heat from the sample may also be transferred by radiating through the ambient 2 environment and can be conducted through the material of the pmbe itself.
Since magnetic flux is proportional to magnet temperature, the magnet upon heating 4 underwent flux changes. These changes in flux altered the homogeneity of the magnet, and thus the results obtained were inaccurate, and iii some cases, worthless.
6 Even, a small change iz~ sample stream temperature was sufficient to cause a major change 7 in the magnetic flux. Frequency locks, such as that disclosed ire U.S.
Patent No. 5,166,620 8 (Panosh), were introduced into probes to counter changes in flux, by controlling the frequency of 9 the 1ZF coils. As for changes in magnetic homogeneity, these can only be made by shimming the magnet.
11 Today, when magnet control is desired in these systems, complex, highly accurate, heat 12 exchangers are employed with these probes. These heat exchangers ate placed in the path of the 13 sample stream prior to its entry into the probe. It has been found that this solution is extremely 14 costly and thus, di~tcult to implement in in-line process environments.
Additionally, the temperature canductiviiy between the magnet and the satuple stream 16 effects the sample itself. With the sample forced to remain in the probe for the desired testing 17 time (period) the sample itself changes as its flow has temporarily ceased during the analysis 18 period. This temperature change can alter NMR test results.
19 Summary of the >fnventiop ''.0 The present invention improves on the contemporary art by providing a dewer type probe 21 device, that allows for thermal shielding of the sample stream from the magnet. This is 22 accomplished by dirninating heat transfer within the probe. This dwicc is particularly suited for 23 use in in-line process environments.
24 The device of the present invention is an NMR pmbe including a body deSning an internal chamber. This chamber is adapted for supporting a vacuum and the body is of a 26 non-magnetic material. A conduit extends through the chamber in the body.
The conduit has a 27 first portion_in communication with second portions, the fnst portion being intermediate the 28 second portions, with the first and second portions of non-magnetic materials with substantially 29 equal thermal expansion coefficients. An RF coil is positioned along at least a substantial P, ~m~~ o0~oo55e ~ ! t; JIW 2001 1 portion of the first conduit portion. It is preferred that this device also include a field or 2 frequency lock unit in the chamber, as well as a Fetter, to allow for degassing in the chamber to 3 maintain the preferred high pressure vacuum.
Brief DescH~tio~Qf The Drawin~a 6 The present invention will be described with reference to the accompanying drawings, 7 wherein like reference numerals or characters identify corresponding or like components. In the 8 drawings:
9 Fig. 1 is a front view of the apparatus of the presant invention;
Fig. 2 is a cut away view of the apparatus of the present invention;
,_. 11 Fig. 3 is a bottom view of the present invention with components removed;
12 Fig. 4 is a cross-sectional view of the present invention, taken along line 4-4 of Fig. 1;
13 Fig. 5 is a cross-sectional view of the present invention, taken along lint S-5 of Fig. 1;
14 and 1 S Fig. 6 is a schematic of the components of the present invention.
17 Detailed Description Of The Drawinis 18 Fig. 1 shows generally the apparatus 20 of the present invention in use with a magnet M
19 (typically having north "'N' and south "S" poles), that generates a magnetic field (indicated by 'V20 the vector Bo). The magnet M is part of an apparatus such as that detailed in U'.S. Patent No.
21 5,371,464, incorporated by reference herein, designed to accommodate tubular or other similarly 22 shaped probes, such as the apparatus 20 of the present invention.
23 The apparatus 20 includes a base 22 and a cap 24, that enclose a cylinder 26. The base 22 24 preferably includes a collar member 27, preferably a separate piece that serves as a heat sink. A
2S conduit 28, through which the fluid to be analyzed passes, extends through the cylinder 26.
26 There is space 30 between the conduit 28 and the inner wall 26a of the cylinder. An RF coil 40 27 preferably journals the conduit 28 along a non-magnetic, preferably z~on-metallic, portion of the 28 conduit 28. The cylizxder 26 in combination with the base 22 and cap 24, are sealed so as to be 29 air tight, such that when operation is desired, the space 30 therein can be completely evacuated, ...'.wrw ~
pC'1'/~~ 00/00558 lp2 ?', JU'N 2001 1 resulting in an ultra high vacuum (on the order of approximately 10's to 10's torr). The apparatus 2 20 includes control electronics attached thereto, and are detailed below.
3 Turning also to Figs. 2 and 3, the apparatus 20 is shown in greater detail.
Field or 4 frequency lock unit or mechanism 43, includes a sealed sample 44 journalcd by a field or Frequency lock RF coil 46, and associated electrnnics, is preferably part of the apps;atus 20, but 6 is not required. This frequency lock unit 43 is, for example, in accordance with that detailed in 7 commonly owned U.S. Patcat No. 5,166,620 (Panosh), incorporated by rofcrcnce herein.
8 RF Coil 40 and frequency lock RF coil 46, terminate in wires 40a, ~tOb, 4ba, 46b, 9 respectively, that connect to the control electronics (detailed below) at feodthroughs SOa, SOb and 52a, 52b. The feedthroughs 50a, 50b, 52a, 52b are positioned in bores 54a, 54b, 56a, 56b in the 11 base 22 by being axed thereto, so as to form an air-tight seal in their respective bores 54a, 54b, __~ 12 56a, 56b. The ~uvires 40a, 40b, 46a, 46b are preferably silver plated copper wires, and preferably 13 threaded thmugh, and mounted in, by welds with non-magnetic materials, proportionally sized 14 openings in guides S8, 59. These guides 58, 59 are preferably of a ceramic or non-magnetic arid non-conductive material, and attached along the conduit 28, at points where the portions forming 16 the conduit 28 attach, and serve to keep the wires 40a, 40b, 46a, 46b properly aligned, so as not 17 to touch each other.
18 A gaffer 60, such as gctters of Typc St172 Standard Letters, sad preferably of type 19 ST172/HI/7-6/150C, Manufacture Code 5K0350, from Saes Letters, Via Gallatate 215, Milan 20151, Italy, is employed to maintain the vacuum, in particular tine high vacuum, in the space 30 21. of the apparatus 20. The garter, as well as any other gaffer employed, is preferably in the form of .~12 a cylinder or the like (although other shapes, e.g. square, rectangle, polygonal, triangular, oval, 23 etc., are also permissible). The gaffer 60 is connected by wires 62a, 62b to feedthroughs 64a, 64b 24 mounted in as air-tight manner in bores 66a, 66b, similar to the feedthroughs SOa, 50b, 52a, 52b detailed above. ThE gaffer !i0 is configured for receiving a voltage, typically approxirnatcly 5 26 volts, through the wires 62a, 52b (in accordance with the wires 40a, 40b;
46a, 46b about), to 27 absorb molecules (typically gases) forrncd in the apparatus as components undergo "degassing"
28 over time, and therefore, maintain the vacuum at the preferred level (detailed above). While a 29 single gaffer 60 is shown, multiple getters are also permissible.
The feedthmughs 50a, SOb, 52a, 52b, 64a, 64b, are preferably made of materials such as 31 K~JVAR brand alloyed metal (CRS Moldings, Ine., Wilmington, Delaware), in a cylinder or the I'E~V~~~ 7 JI 112901 1 like for surrounding the wins. KOVAR is preferred as it has a thermal expansion coefficient 2 similar to that of the material of the base 22, and can be mourrtod in an air tight manner in the 3 bores S4a, S4b, S6a, 56b, 66a, 66b of the base 22. Other materials are also sufficient provided 4 they have suitable thermal expansion coefficients with respect to that of the material of the base.
Other feedthrough shapes, e.g. square, rectangle, polygonal, triangular, oval, ere., are also 6 permissible provided the bores S4a, 54b, 56a, 56b, 66a, 66b of the base 22 are correspondingly 7 shaped.
8 The wires 40a, 40b, 46a, 46b, 62a, 62b extend through the respective feedthroughs SOa, 9 SOb, SZa, 52b, 64a, 64b, with wires 40a, 40b, 46a, 46b connecting to the control electronics, that are partially on lands 67, 68. Each land 67, 68 typically corresponds to control electronics for 11 the RF coil 40 and frequency lock RF coil 46, respectively. Wires 62a, 62b are adapted to V.:12 connect with and receive voltages from extcmal sources, to supply voltage to the garter 60, when 13 operation thereof is desired.
14 A pipe 70 is mounted in as opening 72 in the bast 22, also in an air tight mariner, similar to the fecdthroughs SOa, SOb, 52a,, 52b, 64a, 64b above. The pipe 70 is adapted for connection to 16 a suction source for providing vacuum evacuation, attd is of a material that can be pinched (e.g., 17 crimped) and sealed, typically by brazing (in accordance with that detailed below) or the like, so 18 as to maintain the vacuum. This pipe 70 is preferably made of Copper, but can also be of other 19 materials such as Aluminum or other materials, preferably metals that are soft, so as to be crimped and brazed closed (by brazing operations such as that detailed below) in an air-tight 21 manner, in order to hold the vacuuan at the desired high level.
._..:12 The base 22 may also include connection parts 76a, 76b (in broken lines), such as SMA, 23 for example, Part No. 2006-5010-00 from MA COM, Massachusetts, for permitting connections 24 to the control electronics, in particular, those electronics located on the lands 67, 68, by cables, wires or the like. There are typically at least two connection ports 76a, 76b, one for each of the 26 main RIi coil 40 and field or frequency lock RF coil 46. ~'he cap 24 is similar to the base 22, but 27 typically does not include bores for feedthroughs and pipes, as detailed above. However, if 28 desired, these structures naay be present in the cap 24.
29 The base 22 and cap 24 are made of non-magnetic materials, preferably non-magnetic metals such as stainless steel. Other metals such as Molybdin~um, Titanium, ere. are also suitable.
31 The base 22 and cap 24 may be made of the same or different materials.
Bac ~a of the Invention 7 Nuclear magnetic resonance (NMR) testing of substances to determine the constituents 8 therein is well known in the art. In known devices, the sample is arranged between the poles of a 9 magnet and is enclosed by a wire coil to az~able a sample to be subjected to RF electromagnetic pulses of a predetermined frequency. The resulting NMR pulse generated by the nuclei of the 11 sample under test is detected and processed by the NMR device in a well latlown matuier to 12 identify the sample constituents.
13 NMR analysis may be performed in devices commonly lmown as spectrometers.
These 14 spectrometers are designed so as to have a probe, that accepts the sample to be analyzed, between poles of a magnet. The RF coils and tuning circuitry associated with the probe create a 16 field (B), that rotates the net magnetization of the nucleus- These RF
coils also detect the 17 transverse magne~zation as it processes in the X,Y plane. The RF coil pulses the sample nucleus 18 at the Lamer frequency, so as to generate a readable signal for sample identification.
19 An exemplary probe that performs in accordance with that described immediately above ' i0 is disclosed in commonly owned U.S. Patent No. 5,371,464 (Rapoport), and is incorporated by 21 reference herein. This probe, and others like it, while an improvement in the art, still had several 22 disadvantages. ' 23 The gteatest disadvantage involved temperature changes, particularly temperature 24 increases associated with heating the magnet as a result of the strong thermal conductivity 2S between the sample stream and the magnet itself. This is due mainly to samples that must be ntn 26 through the stream at high ten".peraturcs, so as to remain liquid for analysis, and avoid gelling, 27 solidifying or the like, if cooled. These samples typically dissipate within from the probe, that is 28 transferred through air in the ambient environment, ultimately reaching the magnet and raising um uu~~~
~ 7: JUN 2001 1 its temperature. Heat from the sample may also be transferred by radiating through the ambient 2 environment and can be conducted through the material of the pmbe itself.
Since magnetic flux is proportional to magnet temperature, the magnet upon heating 4 underwent flux changes. These changes in flux altered the homogeneity of the magnet, and thus the results obtained were inaccurate, and iii some cases, worthless.
6 Even, a small change iz~ sample stream temperature was sufficient to cause a major change 7 in the magnetic flux. Frequency locks, such as that disclosed ire U.S.
Patent No. 5,166,620 8 (Panosh), were introduced into probes to counter changes in flux, by controlling the frequency of 9 the 1ZF coils. As for changes in magnetic homogeneity, these can only be made by shimming the magnet.
11 Today, when magnet control is desired in these systems, complex, highly accurate, heat 12 exchangers are employed with these probes. These heat exchangers ate placed in the path of the 13 sample stream prior to its entry into the probe. It has been found that this solution is extremely 14 costly and thus, di~tcult to implement in in-line process environments.
Additionally, the temperature canductiviiy between the magnet and the satuple stream 16 effects the sample itself. With the sample forced to remain in the probe for the desired testing 17 time (period) the sample itself changes as its flow has temporarily ceased during the analysis 18 period. This temperature change can alter NMR test results.
19 Summary of the >fnventiop ''.0 The present invention improves on the contemporary art by providing a dewer type probe 21 device, that allows for thermal shielding of the sample stream from the magnet. This is 22 accomplished by dirninating heat transfer within the probe. This dwicc is particularly suited for 23 use in in-line process environments.
24 The device of the present invention is an NMR pmbe including a body deSning an internal chamber. This chamber is adapted for supporting a vacuum and the body is of a 26 non-magnetic material. A conduit extends through the chamber in the body.
The conduit has a 27 first portion_in communication with second portions, the fnst portion being intermediate the 28 second portions, with the first and second portions of non-magnetic materials with substantially 29 equal thermal expansion coefficients. An RF coil is positioned along at least a substantial P, ~m~~ o0~oo55e ~ ! t; JIW 2001 1 portion of the first conduit portion. It is preferred that this device also include a field or 2 frequency lock unit in the chamber, as well as a Fetter, to allow for degassing in the chamber to 3 maintain the preferred high pressure vacuum.
Brief DescH~tio~Qf The Drawin~a 6 The present invention will be described with reference to the accompanying drawings, 7 wherein like reference numerals or characters identify corresponding or like components. In the 8 drawings:
9 Fig. 1 is a front view of the apparatus of the presant invention;
Fig. 2 is a cut away view of the apparatus of the present invention;
,_. 11 Fig. 3 is a bottom view of the present invention with components removed;
12 Fig. 4 is a cross-sectional view of the present invention, taken along line 4-4 of Fig. 1;
13 Fig. 5 is a cross-sectional view of the present invention, taken along lint S-5 of Fig. 1;
14 and 1 S Fig. 6 is a schematic of the components of the present invention.
17 Detailed Description Of The Drawinis 18 Fig. 1 shows generally the apparatus 20 of the present invention in use with a magnet M
19 (typically having north "'N' and south "S" poles), that generates a magnetic field (indicated by 'V20 the vector Bo). The magnet M is part of an apparatus such as that detailed in U'.S. Patent No.
21 5,371,464, incorporated by reference herein, designed to accommodate tubular or other similarly 22 shaped probes, such as the apparatus 20 of the present invention.
23 The apparatus 20 includes a base 22 and a cap 24, that enclose a cylinder 26. The base 22 24 preferably includes a collar member 27, preferably a separate piece that serves as a heat sink. A
2S conduit 28, through which the fluid to be analyzed passes, extends through the cylinder 26.
26 There is space 30 between the conduit 28 and the inner wall 26a of the cylinder. An RF coil 40 27 preferably journals the conduit 28 along a non-magnetic, preferably z~on-metallic, portion of the 28 conduit 28. The cylizxder 26 in combination with the base 22 and cap 24, are sealed so as to be 29 air tight, such that when operation is desired, the space 30 therein can be completely evacuated, ...'.wrw ~
pC'1'/~~ 00/00558 lp2 ?', JU'N 2001 1 resulting in an ultra high vacuum (on the order of approximately 10's to 10's torr). The apparatus 2 20 includes control electronics attached thereto, and are detailed below.
3 Turning also to Figs. 2 and 3, the apparatus 20 is shown in greater detail.
Field or 4 frequency lock unit or mechanism 43, includes a sealed sample 44 journalcd by a field or Frequency lock RF coil 46, and associated electrnnics, is preferably part of the apps;atus 20, but 6 is not required. This frequency lock unit 43 is, for example, in accordance with that detailed in 7 commonly owned U.S. Patcat No. 5,166,620 (Panosh), incorporated by rofcrcnce herein.
8 RF Coil 40 and frequency lock RF coil 46, terminate in wires 40a, ~tOb, 4ba, 46b, 9 respectively, that connect to the control electronics (detailed below) at feodthroughs SOa, SOb and 52a, 52b. The feedthroughs 50a, 50b, 52a, 52b are positioned in bores 54a, 54b, 56a, 56b in the 11 base 22 by being axed thereto, so as to form an air-tight seal in their respective bores 54a, 54b, __~ 12 56a, 56b. The ~uvires 40a, 40b, 46a, 46b are preferably silver plated copper wires, and preferably 13 threaded thmugh, and mounted in, by welds with non-magnetic materials, proportionally sized 14 openings in guides S8, 59. These guides 58, 59 are preferably of a ceramic or non-magnetic arid non-conductive material, and attached along the conduit 28, at points where the portions forming 16 the conduit 28 attach, and serve to keep the wires 40a, 40b, 46a, 46b properly aligned, so as not 17 to touch each other.
18 A gaffer 60, such as gctters of Typc St172 Standard Letters, sad preferably of type 19 ST172/HI/7-6/150C, Manufacture Code 5K0350, from Saes Letters, Via Gallatate 215, Milan 20151, Italy, is employed to maintain the vacuum, in particular tine high vacuum, in the space 30 21. of the apparatus 20. The garter, as well as any other gaffer employed, is preferably in the form of .~12 a cylinder or the like (although other shapes, e.g. square, rectangle, polygonal, triangular, oval, 23 etc., are also permissible). The gaffer 60 is connected by wires 62a, 62b to feedthroughs 64a, 64b 24 mounted in as air-tight manner in bores 66a, 66b, similar to the feedthroughs SOa, 50b, 52a, 52b detailed above. ThE gaffer !i0 is configured for receiving a voltage, typically approxirnatcly 5 26 volts, through the wires 62a, 52b (in accordance with the wires 40a, 40b;
46a, 46b about), to 27 absorb molecules (typically gases) forrncd in the apparatus as components undergo "degassing"
28 over time, and therefore, maintain the vacuum at the preferred level (detailed above). While a 29 single gaffer 60 is shown, multiple getters are also permissible.
The feedthmughs 50a, SOb, 52a, 52b, 64a, 64b, are preferably made of materials such as 31 K~JVAR brand alloyed metal (CRS Moldings, Ine., Wilmington, Delaware), in a cylinder or the I'E~V~~~ 7 JI 112901 1 like for surrounding the wins. KOVAR is preferred as it has a thermal expansion coefficient 2 similar to that of the material of the base 22, and can be mourrtod in an air tight manner in the 3 bores S4a, S4b, S6a, 56b, 66a, 66b of the base 22. Other materials are also sufficient provided 4 they have suitable thermal expansion coefficients with respect to that of the material of the base.
Other feedthrough shapes, e.g. square, rectangle, polygonal, triangular, oval, ere., are also 6 permissible provided the bores S4a, 54b, 56a, 56b, 66a, 66b of the base 22 are correspondingly 7 shaped.
8 The wires 40a, 40b, 46a, 46b, 62a, 62b extend through the respective feedthroughs SOa, 9 SOb, SZa, 52b, 64a, 64b, with wires 40a, 40b, 46a, 46b connecting to the control electronics, that are partially on lands 67, 68. Each land 67, 68 typically corresponds to control electronics for 11 the RF coil 40 and frequency lock RF coil 46, respectively. Wires 62a, 62b are adapted to V.:12 connect with and receive voltages from extcmal sources, to supply voltage to the garter 60, when 13 operation thereof is desired.
14 A pipe 70 is mounted in as opening 72 in the bast 22, also in an air tight mariner, similar to the fecdthroughs SOa, SOb, 52a,, 52b, 64a, 64b above. The pipe 70 is adapted for connection to 16 a suction source for providing vacuum evacuation, attd is of a material that can be pinched (e.g., 17 crimped) and sealed, typically by brazing (in accordance with that detailed below) or the like, so 18 as to maintain the vacuum. This pipe 70 is preferably made of Copper, but can also be of other 19 materials such as Aluminum or other materials, preferably metals that are soft, so as to be crimped and brazed closed (by brazing operations such as that detailed below) in an air-tight 21 manner, in order to hold the vacuuan at the desired high level.
._..:12 The base 22 may also include connection parts 76a, 76b (in broken lines), such as SMA, 23 for example, Part No. 2006-5010-00 from MA COM, Massachusetts, for permitting connections 24 to the control electronics, in particular, those electronics located on the lands 67, 68, by cables, wires or the like. There are typically at least two connection ports 76a, 76b, one for each of the 26 main RIi coil 40 and field or frequency lock RF coil 46. ~'he cap 24 is similar to the base 22, but 27 typically does not include bores for feedthroughs and pipes, as detailed above. However, if 28 desired, these structures naay be present in the cap 24.
29 The base 22 and cap 24 are made of non-magnetic materials, preferably non-magnetic metals such as stainless steel. Other metals such as Molybdin~um, Titanium, ere. are also suitable.
31 The base 22 and cap 24 may be made of the same or different materials.
~9'~P~e 1 As shown in Fig. 4, which represents the cross-sectional view 4-4 of Fig. 1, the cylinder 2 26 is preferably made of materials such as Molybdenum brazed to stainless steel, and it preferred 3 that its inner wall 26a be shiny, so as to be highly reflective. It is preferred to make this inner 4 wall shiny by techniques such as electro-polishing followed by ultrasonic cleaning. While the base 22, cap 24 sad cylinder 26 arc shown as circular and cylindrical respectively, they may be 6 of other shapes such as squared (rectangular), triangular, etc. The base 22, cap 24, and cylinder 7 26 arc preferably joined together by techniques such as brazing or welding, such that they ate 8 sealod in an sir~tight manner, so as to be able to support the desired ultra high vacuum in the 9 space 30.
The brazing operation preferably uses Palciul 10 of Grapasil 9 as the brazing material, 11 with the brazing process done under vacuum conditions. In one exemplary brazing operation, X12 there is a pumping down for approximately 10 minutes at approximately 700C
and then raising 13 the temperature to 930C for another 10 minutes. The welding operation preferred is TIG welding 14 and for example may be performed with a TIG welder with a 0.020 electrode on a 35-40 setting.
The conduit 28 is detailed in Fig. 5 (which represents the cross-sectional view 5-5 of Fig.
16 1), which will now be described in conjunction with Figs. 1-3. The conduit 28 includes an 17 analysis portion or tube 80, with adapters 82 attached at both ends. These adapters 82 are in turn 18 attached to tube portions 84, that form the remainder of the conduit 28. It is preferred that these 19 conduit portions 80, 82, 84 be aligned so as to be coaxial (along the axis 85). The attachments ate preferably male-female type fits and have been joined together by techniques such as brazing 21 (detailed above). Qthcr fits are joining methods are also permissible.
While a round or ...~2 cylindrical conduit is shown, it could also be other shapod such as square {rectangular) 23 triangular, polygonal, etc.
24 The analysis portion or tube 80 is preferably a ceramic tube, of a ceramic material such as Alumina, for example Alumina 96% or AL 23, available from Frialit-Degussit, Postfach 71 02 26 61, p-68222, Manheim, Germany, that can hold fluids at high pressures arad temperatures. Other 27 non-magnetic, non-metallic materials, such as glass and sapphire are also suitable provided they 28 arc treated to hold fluids at high pressures. The tube 80 is such that the 1Z.F coil 40 can be placed 29 around it, so as to journal it, in either a contacting or non-contacting manner, or combinations thereof (contacting and non.-contacting portions). The tube 80 forms the "male" portion of the ......<.r., ~.~r PcrW 00/00558 ~2 7 JUN 2001 1 male-female fit, with the respective adapters 82. The tube 80 is preferably connected to the 2 respective adapters 82 by techniques such as brazing, as detailed about.
3 The adapters 82, are preferably tubular pieces of materials, preferably metals such as 4 titanium. Titanium is preferred because it has a thermal expansion coefficient similar to that of the ceramic, an in particular Alumina. Other ~tnatcrials may also form these adapters 82, 6 provided they have similar thermal cxpausion coefficients with respect to the material of the tube 7 80. 'The adapters 82 forms the "male" portion of the male-female fit, with the respective tube 8 portions 84.
9 The tube portions 84 are preferably stainless steel or other similar non-magnetic material, and are preferably connected to the respective adapters 82, by tochniques such as brazing or 11 welding (as detailed above). The tube portions 84 extend through bores 8G, 87 in the base 22 and ~V ~~'12 cap 24 respectively, end are sealed in as air-tight manner (as detailed about), so as to preserve 13 the vacuum in the apparatus 20. It is also preferred that the material for the tube portions 84 be 14 of a thermal expansion coefficient similar to that of the tube 80 and adapters 82.
With respect to all of the zmaterials that form the above listed components of the 16 apparatus 20, all of these materials are selected as they degas minimally, if at all, and thus, can 17 hold a passive vacuum for long time periods, typically on the order of years.
18 Fig. 6 details the control electronics, and in particular, the control electronics lands 67, 68 19 for the corresponding RF coil 40 and the frequency Iock RF coil 46. These control electronics lands 67 and 68 are such that they contain tuning and matching circuitry, intermediate the 21 rv-spective coils 40, 46 and SMA connectors 76a, 76b, that are preferably coruxected to a control ~ 2 unit 90, for example a microprocessor, CPU, personal computer, or other computer or similar 23 type device, for controlling the RF Coil 40 and field or frequency lock 1tF
coil 46 in a 24 coordinated manner, with hardware, software or combinations thereof. This tuning and matching circuitry functions to font the RF coil 40 as a high frequency antenna, and match it to an 26 approximately 50 ohm impedance.
27 The tuning and matching circuitry on land 67 includes a series of networked capacitors 28 C7-C11. Capacitors C7, C8 and C11 are High Q chip capacitors and hero for example, are of 29 capacitances of 4.7 picofarads (PF), 33 PF and 3.3 PF, respectively.
Capacitors C9 and C10 are variable 0.8-10 PF and 3-10 PF, respectively, High Q chip capacitors.
..w~w~ew w.~
pCTIIL 00/00558 IPEI~JS ~ ?'t;~ U N 2 0 01 1 The tuning and matching circuitry on land 68 includes a series of networked capacitors 2 C2-C6. Capacitors C3, C4 mad C6 ate High Q chip capacitors and here for example, are of 3 capacitaaces of 180 PF, 2?PF and 5.3 PF, respectively. Capacitors C2 and CS
are variable 4 1-30PF and S-25PF High Q chip capacitors.
In operation, the apparatus 20 is placed inside a magnet, such as that detailed in U.S.
6 Patent No. 5,371,464. Cables are then connected to the SMA connectors 76a, 76b and the 7 apparatus 20 is evacuated to a preferred vacuum of approximately 10's to 10's torn, with the pipe 8 70, crimped and sealed by techniques such as brazing (as detailed above).
The sarrtple is then 9 entered into the apparatus 20, and may either flow through the analysis portion or tube 80 or may remain in a non-flowing manner in the analysis portion or tube 80, when NMR
analysis is ,~ 11 occurring. The NMR analysis, including operation of the RF coil 40 and frequency lock RF coil _,:12 46, including pulse sequence protocols, is in accordance with conventioxaal NMR analysis.
13 While preferred embodiments of the present Invention have beta described, so as to 14 enable ono of skill in the art to practice the present invention, the preceding description is intended to be exemplary only. It should not be used to limit the scope of the invention, which 16 should be determined by reference to the following claims.
_g_ u~~ ~
The brazing operation preferably uses Palciul 10 of Grapasil 9 as the brazing material, 11 with the brazing process done under vacuum conditions. In one exemplary brazing operation, X12 there is a pumping down for approximately 10 minutes at approximately 700C
and then raising 13 the temperature to 930C for another 10 minutes. The welding operation preferred is TIG welding 14 and for example may be performed with a TIG welder with a 0.020 electrode on a 35-40 setting.
The conduit 28 is detailed in Fig. 5 (which represents the cross-sectional view 5-5 of Fig.
16 1), which will now be described in conjunction with Figs. 1-3. The conduit 28 includes an 17 analysis portion or tube 80, with adapters 82 attached at both ends. These adapters 82 are in turn 18 attached to tube portions 84, that form the remainder of the conduit 28. It is preferred that these 19 conduit portions 80, 82, 84 be aligned so as to be coaxial (along the axis 85). The attachments ate preferably male-female type fits and have been joined together by techniques such as brazing 21 (detailed above). Qthcr fits are joining methods are also permissible.
While a round or ...~2 cylindrical conduit is shown, it could also be other shapod such as square {rectangular) 23 triangular, polygonal, etc.
24 The analysis portion or tube 80 is preferably a ceramic tube, of a ceramic material such as Alumina, for example Alumina 96% or AL 23, available from Frialit-Degussit, Postfach 71 02 26 61, p-68222, Manheim, Germany, that can hold fluids at high pressures arad temperatures. Other 27 non-magnetic, non-metallic materials, such as glass and sapphire are also suitable provided they 28 arc treated to hold fluids at high pressures. The tube 80 is such that the 1Z.F coil 40 can be placed 29 around it, so as to journal it, in either a contacting or non-contacting manner, or combinations thereof (contacting and non.-contacting portions). The tube 80 forms the "male" portion of the ......<.r., ~.~r PcrW 00/00558 ~2 7 JUN 2001 1 male-female fit, with the respective adapters 82. The tube 80 is preferably connected to the 2 respective adapters 82 by techniques such as brazing, as detailed about.
3 The adapters 82, are preferably tubular pieces of materials, preferably metals such as 4 titanium. Titanium is preferred because it has a thermal expansion coefficient similar to that of the ceramic, an in particular Alumina. Other ~tnatcrials may also form these adapters 82, 6 provided they have similar thermal cxpausion coefficients with respect to the material of the tube 7 80. 'The adapters 82 forms the "male" portion of the male-female fit, with the respective tube 8 portions 84.
9 The tube portions 84 are preferably stainless steel or other similar non-magnetic material, and are preferably connected to the respective adapters 82, by tochniques such as brazing or 11 welding (as detailed above). The tube portions 84 extend through bores 8G, 87 in the base 22 and ~V ~~'12 cap 24 respectively, end are sealed in as air-tight manner (as detailed about), so as to preserve 13 the vacuum in the apparatus 20. It is also preferred that the material for the tube portions 84 be 14 of a thermal expansion coefficient similar to that of the tube 80 and adapters 82.
With respect to all of the zmaterials that form the above listed components of the 16 apparatus 20, all of these materials are selected as they degas minimally, if at all, and thus, can 17 hold a passive vacuum for long time periods, typically on the order of years.
18 Fig. 6 details the control electronics, and in particular, the control electronics lands 67, 68 19 for the corresponding RF coil 40 and the frequency Iock RF coil 46. These control electronics lands 67 and 68 are such that they contain tuning and matching circuitry, intermediate the 21 rv-spective coils 40, 46 and SMA connectors 76a, 76b, that are preferably coruxected to a control ~ 2 unit 90, for example a microprocessor, CPU, personal computer, or other computer or similar 23 type device, for controlling the RF Coil 40 and field or frequency lock 1tF
coil 46 in a 24 coordinated manner, with hardware, software or combinations thereof. This tuning and matching circuitry functions to font the RF coil 40 as a high frequency antenna, and match it to an 26 approximately 50 ohm impedance.
27 The tuning and matching circuitry on land 67 includes a series of networked capacitors 28 C7-C11. Capacitors C7, C8 and C11 are High Q chip capacitors and hero for example, are of 29 capacitances of 4.7 picofarads (PF), 33 PF and 3.3 PF, respectively.
Capacitors C9 and C10 are variable 0.8-10 PF and 3-10 PF, respectively, High Q chip capacitors.
..w~w~ew w.~
pCTIIL 00/00558 IPEI~JS ~ ?'t;~ U N 2 0 01 1 The tuning and matching circuitry on land 68 includes a series of networked capacitors 2 C2-C6. Capacitors C3, C4 mad C6 ate High Q chip capacitors and here for example, are of 3 capacitaaces of 180 PF, 2?PF and 5.3 PF, respectively. Capacitors C2 and CS
are variable 4 1-30PF and S-25PF High Q chip capacitors.
In operation, the apparatus 20 is placed inside a magnet, such as that detailed in U.S.
6 Patent No. 5,371,464. Cables are then connected to the SMA connectors 76a, 76b and the 7 apparatus 20 is evacuated to a preferred vacuum of approximately 10's to 10's torn, with the pipe 8 70, crimped and sealed by techniques such as brazing (as detailed above).
The sarrtple is then 9 entered into the apparatus 20, and may either flow through the analysis portion or tube 80 or may remain in a non-flowing manner in the analysis portion or tube 80, when NMR
analysis is ,~ 11 occurring. The NMR analysis, including operation of the RF coil 40 and frequency lock RF coil _,:12 46, including pulse sequence protocols, is in accordance with conventioxaal NMR analysis.
13 While preferred embodiments of the present Invention have beta described, so as to 14 enable ono of skill in the art to practice the present invention, the preceding description is intended to be exemplary only. It should not be used to limit the scope of the invention, which 16 should be determined by reference to the following claims.
_g_ u~~ ~
Claims (15)
1. An NMR probe comprising:
a body, said body defining an internal chamber, said chamber adapted for supporting a vacuum, said body of a non-magnetic material;
a conduit extending through said chamber in said body, said conduit having a first portion in communication with second portions, said first portion intermediate said second portions, said first and second portions of non-magnetic materials with substantially equal thermal expansion coefficients; and an RF coil positioned along at least a substantial portion of said first conduit portion.
a body, said body defining an internal chamber, said chamber adapted for supporting a vacuum, said body of a non-magnetic material;
a conduit extending through said chamber in said body, said conduit having a first portion in communication with second portions, said first portion intermediate said second portions, said first and second portions of non-magnetic materials with substantially equal thermal expansion coefficients; and an RF coil positioned along at least a substantial portion of said first conduit portion.
2. The probe of claim 1, additionally comprising a frequency lock unit, said frequency lock unit in operative communication with said RF coil.
3. The probe of claim 1, additionally comprising at least one getter.
4. The probe of claim 1, wherein said first conduit portion includes a ceramic tube.
5. The probe of claim 1, wherein said chamber of said body is adapted to support a vacuum of approximately 10-6 to 10-8 torr.
6. The probe of claim 1, wherein said conduit includes third portions intermediate said first and second portions, said third portions of a non-magnetic material, and of a substantially equal thermal expansion coefficients to said first conduit portion.
7. The probe of claim 4, wherein said ceramic is alumina.
8. The probe of claim 1, wherein said first conduit portion comprises a tube of a material selected from the group comprising: alumina, glass and sapphire.
9. The probe of claim 7, wherein said second portions include stainless steel.
10. The probe of claim 6, wherein said first portion is comprised of alumina, said second portions are comprised of stainless steel, and said third portions are comprised of titanium.
11. The probe of claim 1, wherein said body is cylindrical.
12. The probe of claim 1, wherein said conduit is cylindrical.
13. The probe of claim 3, wherein said RF coil is in operative communication with said at least one getter.
14. The probe of claim 11, wherein, said body is made of materials selected from the group comprising: Stainless steel, Molybdenum, titanium or combinations thereof.
15. The probe of claim 14, wherein said inner walls of said cylindrical body are reflective.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US09/394,906 | 1999-09-13 | ||
| US09/394,906 US6310480B1 (en) | 1999-09-13 | 1999-09-13 | Flow-through probe for NMR spectrometers |
| PCT/IL2000/000558 WO2001020357A1 (en) | 1999-09-13 | 2000-09-12 | Flow-through probe for nmr spectrometers |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2384819A1 true CA2384819A1 (en) | 2001-03-22 |
Family
ID=23560884
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002384819A Abandoned CA2384819A1 (en) | 1999-09-13 | 2000-09-12 | Flow-through probe for nmr spectrometers |
Country Status (8)
| Country | Link |
|---|---|
| US (1) | US6310480B1 (en) |
| EP (1) | EP1218767A4 (en) |
| KR (1) | KR20020060698A (en) |
| CN (1) | CN1175279C (en) |
| AU (1) | AU7309100A (en) |
| CA (1) | CA2384819A1 (en) |
| RU (1) | RU2247405C2 (en) |
| WO (1) | WO2001020357A1 (en) |
Families Citing this family (21)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6774634B2 (en) * | 2002-01-29 | 2004-08-10 | Varian, Inc. | Automated NMR analysis using solvents and sample tube materials to control frequency shifts |
| DE10225958B3 (en) * | 2002-06-12 | 2004-03-04 | Bruker Biospin Ag | Apparatus for positioning an elongate sample tube filled with a measurement substance relative to a NMR receiver coil system |
| US20050040827A1 (en) * | 2003-01-07 | 2005-02-24 | Tal Cohen | NMR probe with flow restriction element |
| US7378848B2 (en) * | 2006-05-05 | 2008-05-27 | M2M Imaging Corp. | Magnetic resonance coil system |
| EP2225574A2 (en) * | 2007-12-21 | 2010-09-08 | Philips Intellectual Property & Standards GmbH | Magnetic resonance safety monitoring systems and methods |
| US7994783B2 (en) * | 2008-02-08 | 2011-08-09 | The Regents Of The Univerisity Of California | Integrated microchip incorporating atomic magnetometer and microfluidic channel for NMR and MRI |
| KR200457983Y1 (en) * | 2008-12-24 | 2012-01-16 | 이영희 | Food and accommodating addition the pot lid which is had |
| US8547110B2 (en) * | 2009-09-22 | 2013-10-01 | Adem, Llc | Impedance sensing systems and methods for use in measuring constituents in solid and fluid objects |
| US9528814B2 (en) | 2011-05-19 | 2016-12-27 | NeoVision, LLC | Apparatus and method of using impedance resonance sensor for thickness measurement |
| US9465089B2 (en) | 2011-12-01 | 2016-10-11 | Neovision Llc | NMR spectroscopy device based on resonance type impedance (IR) sensor and method of NMR spectra acquisition |
| US8952708B2 (en) | 2011-12-02 | 2015-02-10 | Neovision Llc | Impedance resonance sensor for real time monitoring of different processes and methods of using same |
| DK177351B1 (en) * | 2011-12-12 | 2013-02-11 | Nanonord As | A method of determining catalytic fines in an oil |
| KR101339040B1 (en) * | 2012-02-08 | 2013-12-09 | 한국외국어대학교 연구산학협력단 | Solid-state NMR probe of analyzing the structure of LCD panel |
| WO2015070872A1 (en) | 2013-11-13 | 2015-05-21 | Nanonord A/S | A method for quantitative determination of nitrogen in an aqueous fluid |
| CN105806869A (en) * | 2014-12-29 | 2016-07-27 | 丹东东方测控技术股份有限公司 | Industrial on-line nuclear magnetic resonance analyzer |
| US10126380B2 (en) * | 2015-06-15 | 2018-11-13 | Norell, Inc. | Closure and system for NMR sample containers with a secondary locking seal |
| DE102017208841B3 (en) * | 2017-05-24 | 2018-10-04 | Bruker Biospin Ag | NMR probe head with detachable HF seal |
| JP6750819B2 (en) | 2018-04-20 | 2020-09-02 | 国立大学法人大阪大学 | NMR sample tube |
| WO2021037913A1 (en) | 2019-08-27 | 2021-03-04 | Nanonord A/S | A method of and a system for determining fat concentration in a flowable sample by nuclear magnetic resonance |
| WO2021089707A1 (en) | 2019-11-07 | 2021-05-14 | Nanonord A/S | A method of and a system for determining protein concentration in a selected material by nuclear magnetic resonance relaxometry |
| US20240060917A1 (en) | 2020-12-02 | 2024-02-22 | Nanonord A/S | A method of performing quantitative determinations of nitrogen containing units |
Family Cites Families (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3122703A (en) * | 1959-12-21 | 1964-02-25 | Varian Associates | Gyromagnetic resonance method and apparatus |
| US3826972A (en) * | 1973-08-17 | 1974-07-30 | Univ Leland Stanford Junior | Method and apparatus for detecting nuclear magnetic resonance |
| US4489275A (en) | 1982-09-09 | 1984-12-18 | Sri International | High temperature sample heating for spectroscopic studies apparatus |
| US4875486A (en) | 1986-09-04 | 1989-10-24 | Advanced Techtronics, Inc. | Instrument and method for non-invasive in vivo testing for body fluid constituents |
| US4994746A (en) | 1989-09-05 | 1991-02-19 | Advanced Techtronics, Inc. | Method of and apparatus for nuclear magnetic resonance analysis using true logarithmic amplifier |
| US5166620A (en) | 1990-11-07 | 1992-11-24 | Advanced Techtronics, Inc. | Nmr frequency locking circuit |
| US5136261A (en) | 1990-12-11 | 1992-08-04 | Ball Corporation | Saturated absorption double resonance system and apparatus |
| DE4101473C2 (en) * | 1991-01-19 | 1994-03-24 | Bruker Analytische Messtechnik | Probe head for flow-through NMR spectroscopy |
| JPH05329946A (en) * | 1991-02-13 | 1993-12-14 | Toshiba Corp | Fiber reinforced plastic material |
| US5184078A (en) | 1991-03-08 | 1993-02-02 | Elbit-Ati, Ltd. | Apparatus for rotating an nmr test tube |
| EP0584112B1 (en) | 1991-03-08 | 1999-11-10 | Foxboro NMR, Ltd. | Apparatus for in-line analysis of flowing liquid and solid materials by nuclear magnetic resonance |
| US5162734A (en) | 1991-03-08 | 1992-11-10 | Elbit-Ati, Ltd. | Method and apparatus for obtaining an nmr signal having a preselected frequency domain |
| US5633588A (en) * | 1994-09-16 | 1997-05-27 | Hitachi Medical Corporation | Superconducting magnet apparatus using superconducting multilayer composite member, method of magnetizing the same and magnetic resonance imaging system employing the same |
| US5552372A (en) * | 1994-10-27 | 1996-09-03 | General Electric Company | Ceramic superconducting lead resistant to breakage |
| DE69528509T2 (en) * | 1994-10-27 | 2003-06-26 | Gen Electric | Power supply line of superconducting ceramics |
| US5759960A (en) * | 1994-10-27 | 1998-06-02 | General Electric Company | Superconductive device having a ceramic superconducting lead resistant to breakage |
| JP3705861B2 (en) * | 1996-03-21 | 2005-10-12 | 株式会社日立メディコ | Superconducting magnet device and method for adjusting magnetization thereof |
| US5642625A (en) * | 1996-03-29 | 1997-07-01 | The Trustees Of Princeton University | High volume hyperpolarizer for spin-polarized noble gas |
| US6002315A (en) * | 1997-03-17 | 1999-12-14 | General Atomics | Inner cold-warm support structure for superconducting magnets |
-
1999
- 1999-09-13 US US09/394,906 patent/US6310480B1/en not_active Expired - Fee Related
-
2000
- 2000-09-12 CN CNB008141967A patent/CN1175279C/en not_active Expired - Fee Related
- 2000-09-12 AU AU73091/00A patent/AU7309100A/en not_active Abandoned
- 2000-09-12 RU RU2002110103/09A patent/RU2247405C2/en not_active IP Right Cessation
- 2000-09-12 CA CA002384819A patent/CA2384819A1/en not_active Abandoned
- 2000-09-12 EP EP00960944A patent/EP1218767A4/en not_active Withdrawn
- 2000-09-12 KR KR1020027003330A patent/KR20020060698A/en not_active Application Discontinuation
- 2000-09-12 WO PCT/IL2000/000558 patent/WO2001020357A1/en active Application Filing
Also Published As
| Publication number | Publication date |
|---|---|
| US6310480B1 (en) | 2001-10-30 |
| KR20020060698A (en) | 2002-07-18 |
| EP1218767A1 (en) | 2002-07-03 |
| RU2247405C2 (en) | 2005-02-27 |
| WO2001020357A1 (en) | 2001-03-22 |
| AU7309100A (en) | 2001-04-17 |
| CN1175279C (en) | 2004-11-10 |
| EP1218767A4 (en) | 2006-04-26 |
| CN1378650A (en) | 2002-11-06 |
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