CN106596671B - Modularization solid phase temperature-changeable electrochemistry nuclear magnetic resonance is combined probe rod - Google Patents

Abstract

Modular solid-phase variable temperature electrochemical nuclear magnetic resonance probe rod, equipped with a shielded shell, radio frequency interface, electrode interface, sealing plate, heat insulation positioning piece, heat insulation piece, support rod, heat insulation piece, circuit support rod, probe circuit board , temperature control sensor bracket, sample holder, tuning rod, coaxial line, electrode wire, the shielding shell has four side plates and a top cover; the sealing plate is a three-layer structure, and the upper and lower heat insulating positioning pieces are fixed on the upper and lower surfaces of the sealing plate , the support rod and heat shield are modular structures, the lower end of the circuit support rod is connected to the upper end of the temperature control sensor bracket, the probe circuit board is installed between the circuit support rod and the temperature control sensor bracket, and the circuit board is provided with a radio frequency connection interface, There is an inverted T-shaped platform at the bottom of the temperature control sensor bracket, the sample holder is connected to the T-shaped platform, the coaxial line and the electrode wire are respectively connected to the RF interface and the electrode interface of the shielding shell, and pass through the sealing disc to reach the probe circuit board and the sample holder.

Description

Modular solid-phase variable temperature electrochemical nuclear magnetic resonance coupled probe rod

technical field

The invention relates to an electrochemical nuclear magnetic resonance (Electrochemical Nuclear Magnetic Resonance, EC-NMR) coupled experimental technology, in particular to a modular solid-phase variable temperature electrochemical nuclear magnetic resonance coupled probe rod.

Background technique

The conventional nuclear magnetic resonance spectrometer probe is composed of a coil, a tuning matching circuit and various functional supports. The probe extends from the bottom of the magnet to the center of the magnetic field. The sample in the experiment is in a normal temperature environment. The solid-phase low-temperature EC-NMR experiment needs to place the sample in an ultra-low temperature environment as low as the temperature of liquid nitrogen, monitor the reaction process of the electrochemical system in situ, and obtain the NMR information of the intermediate or final product of the electrochemical reaction process. To reveal the electrochemical reaction mechanism at the level. Therefore, conventional NMR spectrometer probes cannot be applied to solid-phase EC-NMR experiments. The probe rod of the EC-NMR system realizes the functions similar to the probe bracket and line interface of the nuclear magnetic resonance spectrometer, and is combined with the cryogenic cavity, coil and tuning matching circuit to form a complete solid-phase low-temperature EC-NMR detection unit. The cryogenic chamber system, the coil circuit, and the probe shaft all need to be developed and developed as a complete stand-alone structure. Since the cryogenic chamber needs to be equipped with a complex vacuum system and refrigerant (liquid nitrogen or liquid helium) delivery system, the cryogenic chamber system is usually composed of general-purpose equipment, such as custom-made commercial cryogenic chambers. Coils and tuning matching circuits currently adopt conventional structures, but electrochemical electrodes and samples will cause the Q value of the coils and the uniformity of the RF field to decrease, which will have a great impact on the signal quality, so the coil structure needs further research and optimization. . The EC-NMR detection unit involves complex factors such as multiple interfaces, shielding, low-temperature heat insulation, wiring, electrode installation, and various coil circuits, and the low-temperature chamber and probe rod extend from the top of the magnet to the center of the magnetic field. The overall length, The coil and sample placement state are different from conventional NMR probes, which require comprehensive design and development of the structure of the probe rod to improve the quality of EC-NMR signals and ensure the safety of experiments.

Some cryogenic chamber products are available with sample positioning devices, for example: Oxford Instruments sample holders and sample holders for spectroscopy cryostat products (https://www.oxford-instruments.com/products/cryogenic- environments/optical-cryostats-for-spectroscopy/cryostat-system-components/sample-holders-and-sample-rods), the structure of these sample rods is an integrated form, the interface is sealed with a single layer, and the sample holder is configured for solid optical samples. In terms of function, it mainly realizes the positioning of the sample, which is inconsistent with the requirements of the EC-NMR combined system. The conventional NMR probe extends from the bottom of the magnet to the center of the magnetic field, and the sample is not placed in an ultra-low temperature state. The structure of the support rod of the conventional NMR probe is relatively consistent. Therefore, the relevant literature and patents of NMR probes mainly describe the circuit structure. For example, the US patent "NMR Probe" (US Patent No.: US7378850B2) approved in 2008 describes a conventional saddle-shaped coil, a unique tuning circuit, and a rotating disk and The nuclear magnetic resonance probe with a structure such as a component switching box, the US patent "Cryogenic NMR Probe" (US Patent No.: US7288939B1) approved in 2007 describes an ultra-low temperature NMR probe, including a saddle coil, a heater, a heat exchanger, Sensors and flanges, etc. On the other hand, in various literature reports on EC-NMR, the development of hardware is concentrated on the probe circuit or electrolytic cell used in EC-NMR, and the electrode interference static magnetic field uniformity that has an important impact on the detection signal, etc. And do not see the report to probe rod. For example: the document "Y.Y.Tong, A.Wieckowski, and E.Oldfield.NMR of Electrocatalysts, J.Phys.Chem.B2002, 106, 2434-2446" reported a probe circuit structure for solid-phase EC-NMR, The document "Richard D. Webster. In Situ Electrochemical-NMR Spectroscopy Reduction of Aromatic Halides. Anal. Chem. 2004, 76, 1603-1610." reports a liquid-phase EC-NMR electrolytic cell.

Contents of the invention

The purpose of the present invention is to provide a supporting framework for various coil circuits of EC-NMR probes, temperature sensor heaters, radio frequency and electrode signals, etc., which can realize convenient and flexible coil circuit replacement and function expansion, can effectively shield electromagnetic interference, and realize good The low-temperature sealing characteristics can realize the positioning of the coil and the sample at ultra-low temperature, thereby improving the signal quality of EC-NMR and ensuring the safety of the experiment. The modular solid-phase variable temperature electrochemical NMR probe rod.

The invention is provided with a shielding shell, a radio frequency interface, an electrode interface, a sealing plate, a thermal insulation positioning sheet, a thermal insulation sheet, a support rod, a heat insulation sheet, a circuit support rod, a probe circuit board, a temperature control sensor bracket, a sample holder, a tuning rod, and a Axis, electrode wire.

The shielding shell is provided with four side panels and a top cover. The four side panels are connected to each other to form a rectangular shell. The top cover is a two-layer structure below the upper circle. The shell and the sealing plate form a double-layer shielding and sealing structure. The radio frequency interface is installed on one side plate of the shielding shell, and the electrode interface is installed on the other side plate of the shielding shell; the sealing plate is a three-layer structure, and the upper layer is square and connected to the shielding shell. The lower sides of the four side covers of the shell are connected, the middle layer is circular, and the lower layer is circular with an enlarged diameter. The edge of the sealing plate is inclined downward and connected with the EC-NMR cryogenic chamber through a clamp and an ○ ring. There is a tuner on the sealing plate Rod through holes and wiring through holes, the upper and lower heat insulation positioning pieces are fixed on the upper and lower surfaces of the sealing plate through the positioning pieces, the bottom of the sealing plate is provided with a connecting handle, and the connecting handle is provided with a positioning hole, and the sealing plate is connected to the upper end of the top support rod through the connecting handle ;The support rod and the heat shield are of modular structure, the heat shield is provided with connecting handles up and down, the support rod and the heat shield are connected through the connection handle, the support rod and the heat shield connecting handle are provided with horizontal positioning holes, and the top The upper end of the support rod is connected with the connecting handle of the sealing plate, the lower end of the circuit support rod is connected with the upper end of the temperature control sensor bracket, the probe circuit board is installed between the circuit support rod and the temperature control sensor bracket, and the circuit board is provided with a radio frequency connection interface. There is an inverted T-shaped platform at the bottom of the control sensor bracket, and the two ends of the horizontal direction are semicircular for installing temperature sensors and heaters; the sample holder is connected to the T-shaped platform and installed on both sides of the platform through screws. The sample positioning hole has coil line positioning holes on both sides of the top; the tuning rod passes through the positioning holes of the shielding shell, heat insulating sheet, sealing plate and heat insulating sheet from the top of the probe rod and enters the sample cavity to reach the probe circuit board. There is a nut, and there is a connecting piece at the bottom. The connecting piece is used to connect with the tuning capacitor. There is a positioning ring in the middle of the connecting piece. The positioning ring is used to support the tuning rod; the coaxial line and the electrode line are respectively connected to the RF interface and the electrode of the shielding case interface through the sealing disc to the probe circuit board and sample holder.

The electrode interface can adopt a filtering connector with a filtering function.

The support rods and heat shields can adopt a multi-section modular structure, and the specific number of sections can be adjusted according to requirements. When new modules such as tuning rods or line interfaces need to be added, the multi-section structure can easily realize functional expansion.

The circuit support rod and the probe circuit board can adopt a modular structure, and when the tuning and matching circuits of the coil are complicated, the one-section structure can be expanded into a smaller-sized two-section structure. The temperature control sensor bracket is suitable for various sizes of solid-phase helical coils and different sample holders of sample tubes, and convenient coil replacement is realized through simple disassembly.

The shielding shell, the sealing disc and the heat insulating positioning piece are made of weakly magnetic metal materials (such as brass), the heat insulating sheets are made of rubber materials, and the support rods and heat insulating sheets can be made of nonmagnetic metal materials (such as oxygen-free copper). The connecting parts at the bottom of the sample holder and the tuning rod are made of special plastic material (such as polyimide) with excellent temperature characteristics, the tuning rod is made of glass fiber rod, and the probe circuit board is made of high-frequency circuit board FR4. The radio frequency interface adopts an N-type connector, and the electrode interface adopts a DB9 filter connector.

The outstanding advantages of the present invention are as follows:

The invention adopts the modular design of the support rod, the heat shield, the temperature control sensor bracket and the sample holder, which can conveniently replace and configure various probe coil circuits according to the needs, and add new functional interfaces and modules; the sample holder adopts materials with excellent temperature characteristics Made of polyimide PI, it can realize the positioning of the coil and the sample at ultra-low temperature; there are horizontal positioning holes at both ends of the support rod and the two ends of the connecting handle of the heat shield, which can ensure the consistency of the position of the tuning rod and other via holes; double-layer The shielding and sealing structure can effectively shield electromagnetic interference and achieve good low-temperature sealing characteristics. The electrode interface adopts filter connectors, which can effectively filter out electromagnetic interference introduced by low-frequency wiring; The screw of the plate can change the sealing degree and the tightness of the tuning rod; the temperature control sensor bracket adopts an inverted T structure, and the horizontal ends are semicircular for installing heaters and sensors. These features have not been reported in the relevant literature of EC-NMR.

Description of drawings

Fig. 1 is a schematic diagram of the overall structure of an embodiment of the present invention.

Fig. 2 is a schematic structural diagram of a shielding case according to an embodiment of the present invention.

FIG. 3 is a schematic diagram of an exploded structure of FIG. 2 .

Fig. 4 is one of the schematic diagrams of the structure of the sealing disc, the heat insulation positioning piece and the heat insulation sheet according to the embodiment of the present invention.

Fig. 5 is the second structural schematic diagram of the sealing plate, the heat insulation positioning piece and the heat insulation piece according to the embodiment of the present invention.

Fig. 6 is a structural schematic diagram of a support rod according to an embodiment of the present invention.

Fig. 7 is a schematic structural diagram of a heat insulating sheet according to an embodiment of the present invention.

Fig. 8 is a schematic diagram of the combined structure of the support rod and the heat insulating sheet according to the embodiment of the present invention.

FIG. 9 is a schematic structural diagram of a circuit support rod according to an embodiment of the present invention.

Fig. 10 is a schematic structural diagram of a temperature control sensor rod according to an embodiment of the present invention.

Fig. 11 is a structural schematic diagram of a circuit support rod, a probe circuit board and a temperature control sensor rod according to an embodiment of the present invention.

Fig. 12 is a schematic diagram of the structure of the sample holder of the embodiment of the present invention.

Fig. 13 is a schematic diagram of the combined structure of the tuning rod and the sample holder according to the embodiment of the present invention.

Detailed ways

The specific implementation of the present invention will be described in detail below in conjunction with the accompanying drawings.

The invention is provided with a shielding shell, a radio frequency interface, an electrode interface, a sealing plate, a thermal insulation positioning sheet, a thermal insulation sheet, a support rod, a heat insulation sheet, a circuit support rod, a probe circuit board, a temperature control sensor bracket, a sample holder, a tuning rod, and a Axis, electrode wire.

The shielding shell is provided with four side panels and a top cover. The four side panels are connected to each other to form a rectangular shell. The top cover is a two-layer structure below the upper circle. The shell and the sealing plate form a double-layer shielding and sealing structure. The radio frequency interface is installed on one side plate of the shielding shell, and the electrode interface is installed on the other side plate of the shielding shell; the sealing plate is a three-layer structure, and the upper layer is square and connected to the shielding shell. The lower sides of the four side covers of the shell are connected, the middle layer is circular, and the lower layer is circular with an enlarged diameter. The edge of the sealing plate is inclined downward and connected with the EC-NMR cryogenic chamber through a clamp and an ○ ring. There is a tuner on the sealing plate Rod through holes and wiring through holes, the upper and lower heat insulation positioning pieces are fixed on the upper and lower surfaces of the sealing plate through the positioning pieces, the bottom of the sealing plate is provided with a connecting handle, and the connecting handle is provided with a positioning hole, and the sealing plate is connected to the upper end of the top support rod through the connecting handle ;The support rod and the heat shield are of modular structure, the heat shield is provided with connecting handles up and down, the support rod and the heat shield are connected through the connection handle, the support rod and the heat shield connecting handle are provided with horizontal positioning holes, and the top The upper end of the support rod is connected with the connecting handle of the sealing plate, the lower end of the circuit support rod is connected with the upper end of the temperature control sensor bracket, the probe circuit board is installed between the circuit support rod and the temperature control sensor bracket, and the circuit board is provided with a radio frequency connection interface. There is an inverted T-shaped platform at the bottom of the control sensor bracket, and the two ends of the horizontal direction are semicircular for installing temperature sensors and heaters; the sample holder is connected to the T-shaped platform and installed on both sides of the platform through screws. The sample positioning hole has coil line positioning holes on both sides of the top; the tuning rod passes through the positioning holes of the shielding shell, heat insulating sheet, sealing plate and heat insulating sheet from the top of the probe rod and enters the sample cavity to reach the probe circuit board. There is a nut, and there is a connecting piece at the bottom. The connecting piece is used to connect with the tuning capacitor. There is a positioning ring in the middle of the connecting piece. The positioning ring is used to support the tuning rod; the coaxial line and the electrode line are respectively connected to the RF interface and the electrode of the shielding case interface through the sealing disc to the probe circuit board and sample holder.

The electrode interface can adopt a filtering connector with a filtering function.

The support rods and heat shields can adopt a multi-section modular structure, and the specific number of sections can be adjusted according to requirements. When new modules such as tuning rods or line interfaces need to be added, the multi-section structure can easily realize functional expansion.

The circuit support rod and the probe circuit board can adopt a modular structure, and when the tuning and matching circuits of the coil are complicated, the one-section structure can be expanded into a smaller-sized two-section structure. The temperature control sensor bracket is suitable for various sizes of solid-phase helical coils and different sample holders of sample tubes, and convenient coil replacement is realized through simple disassembly.

The shielding shell, the sealing disc and the heat insulating positioning piece are made of weakly magnetic metal materials (such as brass), the heat insulating sheets are made of rubber materials, and the support rods and heat insulating sheets can be made of nonmagnetic metal materials (such as oxygen-free copper). The connecting parts at the bottom of the sample holder and the tuning rod are made of special plastic material (such as polyimide) with excellent temperature characteristics, the tuning rod is made of glass fiber rod, and the probe circuit board is made of high-frequency circuit board FR4. The radio frequency interface adopts an N-type connector, and the electrode interface adopts a DB9 filter connector.

Specific examples are given below.

Figure 1 shows a schematic diagram of the overall structure of the embodiment of the present invention, the embodiment of the present invention includes shielding shells 1a to 1e, radio frequency interface 2, electrode interface 3, sealing disc 4, heat insulating positioning pieces 5a and 5b, heat insulating sheets 6a and 6b, support Rods 7a-7e, heat shields 8a-8e, circuit support rod 9, probe circuit board 10, temperature control sensor bracket 11, sample holder 12, tuning rods 13a-13d, coaxial line 14, electrode wire 15. The assembly sequence from top to bottom is: shielding shell top cover 1e, shielding shell side plates 1a~1d, upper heat insulating positioning piece 5a, upper heat insulating plate 6a, sealing disc 4, lower heat insulating plate 6b, lower heat insulating positioning plate 5b, support Rod 7a, heat shield 8a, support rod 7b, heat shield 8b, support rod 7c, heat shield 8c, support rod 7d, heat shield 8d, support rod 7e, heat shield 8e, circuit support rod 9, probe The circuit board 10, the temperature control sensor bracket 11, the sample holder 12, the tuning rods 13a to 13d are self-shielded on the top cover of the shell, and reach the upper end of the probe circuit board 10 along the positioning holes of each module, and one end of the coaxial line 14 is connected to the radio frequency interface 2, The other end reaches the RF connector on the probe circuit board 10 along the positioning holes of each module, and one end of the electrode wire 15 is connected to the electrode interface 3, and reaches the probe circuit board 10 along the positioning holes of each module. The radio frequency interface 2 is installed on the shielding case 1a, and the electrode interface 3 is installed on the shielding case 1b. In this example, the support rod and the heat shield adopt a 5-section modular structure, the circuit support rod 9 and the probe circuit board 10 adopt a 1-section structure, and the sample holder 12 is suitable for a solid-phase helical coil 5mm sample tube, and 4 tuning rods are used. 1 RF line and 1 electrode line. The overall length and aperture of the probe rod match the depth and inner diameter from the top of the magnet to the center of the magnetic field. In this example, the distance from the bottom of the sealing plate to the center of the sample holder is 1100mm, and the diameter of the heat shield is 50mm.

The structure of the shielding shell of the present invention is shown in FIGS. 2 and 3 . The shielding case is composed of side plates 1a, 1b, 1c, 1d and a top cover 1e. 1a-1d are assembled with each other through side screws to form a rectangular housing, and are assembled on the square side of 1e through screws at the upper end. The two inner sides of 1b are provided with screw positioning connection ears 1b-1, 1b-2, 1b-3 and 1b-4, and the two inner sides of 1d are provided with screw positioning connection ears 1d-1, 1d-2, 1d-3 and 1d-4. The side panel is 50mm wide, 10mm long, and 2mm thick. The inner four sides adopt a concave structure, which can be tightly closed during assembly. The top cover 1e is a double-layer member, the upper layer is a circular structure with a diameter of 75 mm and a thickness of 3 mm, and the lower layer is a square structure with a side length of 50 mm and a thickness of 7 mm. The top cover 1e is provided with four tuning rod positioning holes 1e-1×4, the top of the circular structure is provided with a ground wire connection counterbore thread for connecting the ground wire, and the side of the square structure has screw assembly holes 1e-2 for Assemble the side panels. The radio frequency interface 2 is assembled on the through hole of the side plate 1a, and the electrode interface 3 is assembled on the through hole of the side plate 1b.

The structures of the sealing disc, the heat insulating positioning sheet and the heat insulating sheet of the present invention are shown in Fig. 4 and Fig. 5 . The sealing disc 4 is a three-layer component, the upper layer is square, and is assembled with the side plate of the shielding shell through the screw holes 4-4 on the side, and the middle layer is circular, with a diameter of 50mm and a thickness of 7mm, which is used to provide operating space for the connecting clamp . The lower layer is circular, with a diameter of 75mm and a thickness of 7mm, with the edges inclined downwards, connected with the EC-NMR cryogenic chamber through clamps and ○ rings. The sealing disc is provided with a tuning rod positioning hole 4-1, a signal line positioning hole 4-2, a heat insulating sheet positioning screw hole 4-3, and the tuning rod positioning hole 4-1 and the signal line positioning hole 4-2 are through holes. The upper heat insulating sheet 5a is a square rubber sheet with a thickness of 2 mm, and the side length is 50 mm. hole 5a-1, signal line positioning hole 5a-2 and screw hole 5a-3. The upper heat insulation positioning piece 6a is a square metal sheet with a thickness of 2mm and a side length of 50mm. The positioning hole 6a-1, the signal line positioning hole 6a-2 and the screw hole 6a-3, and the upper heat insulating sheet 5a are installed between the positioning sheet 6a and the upper layer of the sealing disc. The lower heat insulating sheet 5b is a circular rubber sheet with a thickness of 2 mm and a diameter of 50 mm. Hole 5b-1, signal line positioning hole 5b-2 and screw hole 5b-3. The lower heat insulation positioning piece 6b is a circular metal sheet with a thickness of 2 mm and a diameter of 50 mm. It is provided with a tuning rod that is consistent with the tuning rod positioning hole 4-1, the signal line positioning hole 4-2, and the heat insulation sheet positioning screw hole 4-3. The positioning hole 6b-1, the signal line positioning hole 6b-2 and the screw hole 6b-3, the lower heat insulating sheet 5 is not installed between the positioning sheet 6 and the lower layer of the sealing disc. During the experiment, it is necessary to turn the tuning rod to tune the probe. There is a gap between the tuning rod and the positioning hole, which makes the airtightness of the cryogenic chamber worse. Therefore, it is necessary to minimize the gap between the tuning rod and the positioning hole. By adjusting the mounting screws, the heat insulation positioning piece is pressed against the heat insulation sheet, and the heat insulation sheet will expand at the gap to fill the gap, thereby achieving the purpose of improving the sealing performance. The bottom of the sealing disc is provided with a connecting handle 4-5, which has an internal thread, is connected with the upper end of the top support rod 8a, and sets the positioning hole 4-6 to realize horizontal positioning.

The supporting rod and heat insulating sheet of the present invention are shown in Figures 6-8. The figure shows a schematic view of the support rod 7a, the heat insulation sheet 8a and the combined module. The support rod 7a is a rod-shaped structure with a diameter of 7mm, and the two ends are M5 bolts with a length of 10mm. The bolts are provided with horizontal positioning holes 7a-1 and 7a-2, and the horizontal positioning holes 7a-1 and 7a-2 are threaded through M3. hole. The structure of the support rods 7b, 7c, 7d, 7e is consistent with that of the support rod 7a. The heat shield 8a is a circular non-magnetic metal sheet with a thickness of 2.5mm and a diameter of 5mm. There are connecting handles at both ends. A counterbore with a depth of 10mm and a diameter of 7mm. The inner layer is an M5 screw hole with a depth of 10mm. The middle part of the outer layer is provided with horizontal positioning holes 8a-7 and 8a-8. The positioning holes are 3mm wide and 4mm long. The heat shield is provided with tuning rod positioning holes 8a-1, 8a-2, 8a-3 and 8a-4, radio frequency coaxial line positioning holes 8a-5, and electrode wire positioning holes 8a-6. The positions and sizes of these positioning holes are the same as The corresponding positioning holes of the sealing disc are consistent. The support rod is assembled to the connecting handle of the heat shield through the bolt at the end, and the horizontal positioning holes of the two are kept coincident, and are fixed by screws. The structure of heat insulating sheets 8b, 8c, 8d and 8e is consistent with that of 8a.

The circuit support rod, the probe circuit board and the temperature control sensor bracket of the present invention are shown in Figures 9-11. The coil circuit support rod 9 is a rod-shaped structure with a diameter of 7mm. The upper end is an M5 bolt with a length of 10mm. The bolt is provided with a horizontal positioning hole 9-1. The lower end is a connecting handle with a length of 25mm, an outer diameter of 10mm, and an inner diameter of 20mm. Double-layer structure, the outer layer is a counterbore with a depth of 10mm and a diameter of 7mm, the inner layer is an M5 screw hole with a depth of 10mm, and the middle of the outer layer is provided with a horizontal positioning hole 9-2, and the upper end of the circuit support rod 9 is connected to the lower part of the heat insulation sheet 8e The handle is connected, and the lower end is connected with the temperature control sensor bracket 11, and the probe circuit board 10 is clamped in the middle. The temperature control sensor bracket 11 is an inverted T-shaped structure, the longitudinal direction is a rod-shaped structure with a diameter of 5mm, the upper end is an M5 bolt with a length of 10mm, and the bottom of the bolt is a connecting section 11-2 with a length of 10mm and a diameter of 7mm. Below the horizontal positioning hole 11-1 and the connecting section 11-2 is a fastening section 11-3 with a diameter of 10mm and a thickness of 2.5mm, which is used for assembling the probe circuit board. The temperature control sensor support 11 is horizontally a rectangular platform 11-4 with a length of 36mm, a width of 12mm and a thickness of 6mm. The heater is in contact with the platform and transfers most of the heat to the platform, through which the environment can be heated quickly and evenly. The temperature sensor is pasted on the platform and does not touch the platform to detect the temperature in the environment. Mounting holes 11 - 5 of M3 are provided on both sides of the platform for assembling the sample holder 12 . A square area with a depth of 3mm and a length of 12mm in the middle of the lower platform is used for combining with the sample holder 12. The probe circuit board 10 is provided with a radio frequency coaxial interface 10-1 for connecting a radio frequency coaxial line.

The sample holder of the present invention is shown in FIGS. 12 and 13 . The sample seat 12 is a bench structure with a length of 31 mm, a width of 12 mm and a height of 21 mm. The thickness of the transverse surface is 6 mm, and the middle is a concave area with a thickness of 3 mm and a length of 12 mm, which is used for assembly with the temperature control sensor bracket 11. Four square connecting handles 12-1 protrude from both ends of the concave area, with a length of 6 mm and a thickness of 3 mm. The connecting handle is provided with an M3 positioning hole 12-2 for assembling the sample holder on the assembly hole 11-5 of the temperature control sensor bracket 11 through screws. Coil positioning holes 12-4 are arranged at both ends of the transverse surface, and 12-4 is a through hole, because the connecting wire of the coil is a flat copper wire, so 12-4 adopts a slit-like structure. The two legs of the bench shape are 15 mm high and 3 mm thick, and a sample installation positioning hole 12-3 with a diameter of 5.1 mm is provided in the middle. The solenoid coil and 5mm sample tube used in solid-phase EC-NMR are installed between the two legs. The two ends of the coil are welded on the flat copper wire, the axial center is consistent with the axial center of 12-3, and the 5mm sample tube passes through Pass the coil, and frame it on the installation positioning hole 12-3.

Claims (15)

1. Modular solid-phase variable temperature electrochemical nuclear magnetic resonance probe rod, which is characterized in that it is equipped with a shielding shell, a radio frequency interface, an electrode interface, a sealing plate, a heat insulation positioning piece, a heat insulation piece, a support rod, a heat insulation piece, and a circuit support Rod, probe circuit board, temperature control sensor bracket, sample holder, tuning rod, coaxial cable, electrode wire; The shielding shell is provided with four side panels and a top cover. The four side panels are connected to each other to form a rectangular shell. The top cover is a two-layer structure below the upper circle. The shell and the sealing plate form a double-layer shielding and sealing structure. The radio frequency interface is installed on one side plate of the shielding shell, and the electrode interface is installed on the other side plate of the shielding shell; the sealing plate is a three-layer structure, and the upper layer is square and connected to the shielding shell. The lower sides of the four side covers of the shell are connected, the middle layer is circular, and the lower layer is circular with an enlarged diameter. The edge of the sealing plate is inclined downward and connected with the EC-NMR cryogenic chamber through a clamp and an ○ ring. There is a tuner on the sealing plate The upper and lower heat insulating sheets are fixed on the upper and lower surfaces of the sealing plate through the heat insulating positioning plate. The bottom of the sealing plate is provided with a connecting handle, and the connecting handle is provided with a positioning hole. The sealing plate is connected to the upper end of the top support rod through the connecting handle. ;The support rod and the heat shield are of modular structure, the heat shield is provided with connecting handles up and down, the support rod and the heat shield are connected through the connection handle, the support rod and the heat shield connecting handle are provided with horizontal positioning holes, and the top The upper end of the support rod is connected to the connecting handle of the sealing plate, the lower end of the circuit support rod is connected to the upper end of the temperature control sensor bracket, the probe circuit board is installed between the circuit support rod and the temperature control sensor bracket, and the probe circuit board is provided with a radio frequency connection interface. There is an inverted T-shaped platform at the bottom of the temperature control sensor bracket, and the horizontal ends are semicircular for installing temperature sensors and heaters; the sample holder is connected to the T-shaped platform and installed on both sides of the platform through screws, and the two ends of the sample holder There are sample positioning holes, and there are coil line positioning holes on both sides of the top; the tuning rod passes through the positioning holes of the shielding shell, heat insulating sheet, sealing plate and heat insulating sheet from the top of the probe rod into the sample cavity to reach the probe circuit board, and the bottom is equipped with Connecting piece, the connecting piece is used to connect with the tuning capacitor, there is a positioning ring in the middle of the connecting piece, and the positioning ring is used to support the tuning rod; the coaxial line and the electrode line are respectively connected to the RF interface and the electrode interface of the shielding case, passing through the sealing disc to reach Probe circuit board and sample holder. 2. The modularized solid-phase variable temperature electrochemical nuclear magnetic resonance probe rod as claimed in claim 1, characterized in that the electrode interface adopts a filter connector. 3. The modularized solid-phase variable temperature electrochemical nuclear magnetic resonance coupled probe rod as claimed in claim 1, characterized in that the top of the tuning rod is provided with a nut. 4. The modularized probe rod for solid-phase variable temperature electrochemical NMR as claimed in claim 1, characterized in that the support rod and the heat shield adopt a multi-section modular structure. 5. The modularized probe rod for solid-phase variable temperature electrochemical nuclear magnetic resonance as claimed in claim 1, characterized in that the circuit support rod and the probe circuit board adopt a modular structure. 6. The modularized solid-phase variable temperature electrochemical NMR probe rod as claimed in claim 1, characterized in that the shielding shell, the sealing disc and the heat-insulating positioning piece are made of weakly magnetic metal materials. 7. The modular solid-phase variable temperature electrochemical NMR probe rod as claimed in claim 6, characterized in that the shielding shell, the sealing disc and the heat insulating positioning piece are made of brass. 8. The modular solid-phase variable temperature electrochemical nuclear magnetic resonance probe rod as claimed in claim 1, characterized in that the heat insulating sheet is made of rubber material. 9. The modularized solid-phase variable temperature electrochemical nuclear magnetic resonance coupled probe rod as claimed in claim 1, characterized in that the support rod and the heat shield are made of non-magnetic metal materials. 10. The modularized solid-phase variable temperature electrochemical nuclear magnetic resonance probe rod as claimed in claim 9, characterized in that the support rod and heat shield are made of oxygen-free copper. 11. The modular solid-phase variable temperature electrochemical NMR probe rod according to claim 1, characterized in that the sample holder and the bottom connecting part of the tuning rod are made of special plastic materials with excellent temperature characteristics. 12. The modular solid-phase variable temperature electrochemical nuclear magnetic resonance probe rod as claimed in claim 11, characterized in that the connecting piece at the bottom of the sample holder and the tuning rod is made of polyimide. 13. The modular solid-phase variable temperature electrochemical NMR probe rod according to claim 1, characterized in that the tuning rod is a glass fiber rod. 14. The modularized probe rod for solid-phase variable temperature electrochemical nuclear magnetic resonance as claimed in claim 1, characterized in that the probe circuit board is a high-frequency circuit board FR4. 15. The modularized probe rod for solid-phase variable temperature electrochemical nuclear magnetic resonance as claimed in claim 1, characterized in that the radio frequency interface adopts an N-type connector, and the electrode interface adopts a DB9 filter connector.