A capillary heating element and heating system for XRD and XAS tests

Abstract

The present invention discloses a capillary heating element for XRD and XAS tests, which is characterized by comprising a heating body, a connecting part and a temperature measuring device; the heating body includes a core body and a housing, the core body is columnar, and a capillary channel coaxial with the core body is formed thereon; the housing is wrapped around the core body, and a cavity is formed between the housing and the core body; a heating wire is arranged in the cavity; there are two heating bodies, and the two heating bodies are arranged coaxially; both ends of the connecting part are respectively connected to the opposite end faces of the two heating bodies, and a window is formed between the connecting part and the heating body; the temperature measuring device is located at the central position of the connecting part. The present invention also provides a heating system. The advantages of the present invention are that it can be directly heated by power-on during use. Compared with conventional air heaters, it does not require a complex supporting system, does not use a gas source, saves equipment costs, and is also easy to maintain.

Description

Technical Field

[0001] The present invention belongs to the technical field of experimental equipment, and particularly relates to a capillary heating element and a heating system for XRD and XAS tests. Background Art

[0002] Capillaries are often used as liquid sample cells to achieve experimental tests such as XRD, XAS, SAXS, etc. When using a capillary as a sample cell for in-situ variable-temperature X-ray related tests on liquids, in order to have sufficient spatial range for the X-ray channel, an air heater is generally used to heat the liquid in the capillary. However, the air heater requires a lot of supporting devices, such as a stable and clean high-pressure gas source, a flow control system, an air heating element, a temperature controller, etc., and then achieves heating by consuming a large amount of gas. That is, the air heater system is complex, and the equipment cost and operating cost are relatively high. Summary of the Invention

[0003] The technical problem to be solved by the present invention is that when using a capillary as a sample cell to collect XRD and XAS data, using an air heater to heat the capillary has a complex system and high cost.

[0004] The present invention adopts the following technical solutions to solve the above technical problems:

[0005] A capillary heating element for XRD and XAS tests includes a heating body, a connecting part, and a temperature measuring device; the heating body includes a core body and a shell, the core body is columnar, and a capillary channel coaxial with the core body is formed thereon; the shell wraps around the core body, and a cavity is formed between the shell and the core body; a heating wire is arranged in the cavity; there are two heating bodies, and the two heating bodies are coaxially arranged; both ends of the connecting part are respectively connected to the opposite end faces of the two heating bodies, and a window is formed between the connecting part and the heating body; the temperature measuring device is located at the middle position of the connecting part.

[0006] Preferably, for the capillary heating element for XRD and XAS tests of the present invention, both the core body and the shell are cylindrical and coaxially arranged.

[0007] Preferably, for the capillary heating element for XRD and XAS tests of the present invention, in the direction perpendicular to the axis of the heating body, the connecting part is fan-shaped, and the arc surface of the fan is flush with the outer side surface of the heating body.

[0008] Preferably, for the capillary heating element for XRD and XAS tests of the present invention, the angle of the fan is 80 - 100°.

[0009] Preferably, for the capillary heating element for XRD and XAS tests of the present invention, the angle of the fan is 90°.

[0010] Preferably, for the capillary heating element for XRD and XAS tests of the present invention, the heating wire is wound around the core body.

[0011] Preferably, for the capillary heating element for XRD and XAS tests of the present invention, the heating wire is an armored heating wire.

[0012] Preferably, for the capillary heating element for XRD and XAS tests of the present invention, the heating wires on the two heating bodies are one.

[0013] Preferably, for the capillary heating element for XRD and XAS tests of the present invention, the temperature measuring device is a thermal resistance or a thermocouple.

[0014] The present invention also provides a heating system for a capillary tube, including a heating element and a temperature controller. The heating element is the above-mentioned capillary heating element for XRD and XAS tests, and the heating wire and the temperature measuring device are both connected to the temperature controller.

[0015] Advantages of the technology of the present invention:

[0016] The heating element described in the technical solution of the present invention is used to locally heat the capillary tube, which can meet the requirements of X-ray related experimental tests; when in use, it can be directly heated by electricity. Compared with the current conventional air heaters, it does not require a complex supporting system, does not use a gas source, saves equipment costs, and is also easy to maintain. Description of the drawings

[0017] Figure 1 is a schematic structural diagram of a capillary heating element for XRD and XAS tests according to an embodiment of the present invention;

[0018] Figure 2 is Figure 1 a cross-sectional view in one direction, and the walls at both ends of the heating body are not shown in the figure;

[0019] Figure 3 is Figure 1 a cross-sectional view in another direction, and the temperature measuring device is not shown in the figure;

[0020] Figure 4 is a schematic structural diagram when the capillary heating element for XRD and XAS tests according to the embodiment is assembled with the capillary tube;

[0021] Figure 5 is a schematic working state diagram when the capillary tube is heated by the heating element described in this embodiment and XRD and XAS data are collected. Detailed implementation manners

[0022] To facilitate the understanding of the technical solution of the present invention by those skilled in the art, the technical solution of the present invention will be further described below in conjunction with the accompanying drawings of the specification.

[0023] As Figure 1 and Figure 2 shown, this embodiment discloses a capillary heating element for XRD and XAS tests, which is used for a capillary as a sample cell for liquid-phase reactions and heats when collecting XRD and XAS signals. The heating element includes two heating bodies 1, a connecting part 2 and a temperature measuring device 3.

[0024] The heating body 1 includes a core body 11, a housing 12 and a heating wire 13.

[0025] The core body 11 is columnar, and a capillary channel 14 is formed thereon; the housing 12 is wrapped around the core body 11, and a cavity (not marked in the figure) is formed between the housing 12 and the core body 11, and the heating wire 13 is arranged in the cavity. Preferably, in this embodiment, both the core body 11 and the housing 12 are cylindrical, and the capillary channel 14, the core body 11, and the housing 12 are coaxially arranged; the heating wire 13 is an armored heating wire, and it is wound around the core body 11, so that the heating wire 13 is in insulating contact with the core body 11 to ensure safe use.

[0026] The two heating bodies 1 are coaxially arranged and connected by the connecting part 2. The two ends of the connecting part 2 are respectively connected to the opposite end faces of the two heating bodies 1, and a window 4 is formed between the connecting part 2 and the heating body 1, and this window 4 constitutes the X-ray transmission channel.

[0027] More specifically, referring to Figure 3 , along the axial direction of the core body 1, the connecting part 2 is fan-shaped, and its arc surface is flush with the outer side surface of the heating body 1. The angle of this fan shape is adjusted within the range of 80 - 100°, and the angle in this embodiment is set to 90°. The purpose of setting the window 4 is to allow X-rays to pass through. In addition, the uniformity of the liquid temperature in the capillary needs to be considered. Therefore, in terms of design dimensions, on the premise of ensuring the transmission of X-rays, the smaller the size of the window 4, the better, that is, under the condition of ensuring the passage of X-rays, the shorter the length of the connecting part 2, the better. For example, in this embodiment, the length of the heating body is 35 mm, and the length of the connecting part 2 is 5 mm.

[0028] The temperature measuring device 3 is used to detect the heating temperature. The temperature measuring device 3 can select a thermal resistance or a thermocouple, and an A-grade platinum resistance is used in this embodiment. During assembly, an installation hole 21 (not marked in the figure) is provided at the central position of the connecting part 2, and then the temperature measuring resistance of the temperature measuring device 3 is inserted into this installation hole 21.

[0029] In this embodiment, the heating wires 13 on the two heating elements 1 adopt a continuous heating wire, and the middle part is arranged outside the heating element. Of course, the middle part of the heating wire 13 can also be arranged inside the heating element. At this time, the connecting part 2 is a hollow structure and communicates with the cavities of the two heating elements 1 to allow the heating wire 13 to pass through.

[0030] In addition, both ends of the capillary channel 14 are machined into screw holes for connecting with other supporting components during experiments.

[0031] Connect the heating wire 13 of the above-mentioned heating element, the temperature measuring device 3 and a temperature controller (not shown in the figure), and a heating system is formed.

[0032] Apply the above-mentioned heating system to locally heat the capillary. As Figure 4 shown, insert the capillary 5 into the capillary channel 14, set the heating element at the part to be heated, and start the temperature controller to locally heat the capillary.

[0033] The heating element described in this embodiment has two symmetrically arranged heating elements 1, and a window 4 is formed in the area between the two heating elements 1. X-rays pass through the solution at this window 4 to collect relevant signals such as XRD and XAS. The reaction solution in the irradiated area is heated relatively evenly and is relatively close to the temperature measuring device 3, and the measured temperature meets the set requirements. In addition, since the angular range during XRD testing is very large, the angle of the window in this embodiment is set at 260 - 280°.

[0034] Figure 5 The figure shows a working state diagram of heating the reaction solution in the capillary 5 by using the heating element described in this embodiment and collecting XRD and XAS signals in this state. In the illustrated state, X-rays enter horizontally from left to right and vertically irradiate the capillary at the window 4. T-XAS is the transmission mode absorption spectrum, and F-XAS is the fluorescence mode absorption spectrum. Select one of them for testing according to the actual situation. When collecting data, the front ionization chamber collects the intensity of the incident light, the rear ionization chamber collects the transmission X-ray absorption spectrum (T-XAS), the fluorescence ionization chamber collects the fluorescence absorption spectrum (F-XAS), and the diffraction data is obtained by the XRD detector Mythen. The diffraction collection angle is generally 20 - 120°. For the above several experimental collections, there are requirements for the spatial layout of the heating element and the capillary 5. The heating element described in this embodiment can well meet various spatial distribution requirements, and while uniformly heating the local reaction solution in the capillary 5, high-quality X-ray related test data can be obtained.

[0035] The technical solution of the present invention has been described exemplarily above in conjunction with the accompanying drawings. Obviously, the specific implementation of the present invention is not limited by the above-mentioned manner. As long as various non-substantive improvements are made by adopting the method concept and technical solution of the present invention, or the concept and technical solution of the invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. A capillary heating element for XRD and XAS tests, characterized in that, It includes a heating body, a connecting part and a temperature measuring device; the heating body includes a core body and a housing, the core body is columnar, and a capillary channel coaxial with the core body is formed thereon; the housing is wrapped around the core body, and a cavity is formed between the housing and the core body; a heating wire is arranged in the cavity; there are two heating bodies, and the two heating bodies are arranged coaxially; both ends of the connecting part are respectively connected to the opposite end faces of the two heating bodies, and a window is formed between the connecting part and the heating body; the temperature measuring device is located at the central position of the connecting part, both ends of the capillary channel are processed into screw holes and are connected to other supporting components during experiments; the capillary is longer than the capillary heating element; in the direction perpendicular to the axis of the heating body, the connecting part is fan-shaped, and the arc surface of the fan is flush with the outer side surface of the heating body.

2. The capillary heating element for XRD and XAS tests according to claim 1, wherein, Both the core body and the housing are cylindrical and are arranged coaxially.

3. A capillary heating element for XRD and XAS tests according to claim 1, characterized in that The angle of the fan is 80 - 100°.

4. A capillary heating element for XRD and XAS tests according to claim 3, characterized in that, The angle of the fan is 90°.

5. The capillary heating element for XRD and XAS tests according to claim 1, characterized in that, The heating wire is wound around the core body.

6. The capillary heating element for XRD and XAS tests according to claim 1 or 5, characterized in that, The heating wire is an armored heating wire.

7. The capillary heating element for XRD and XAS tests according to claim 6, characterized in that, The heating wires on the two heating bodies are one piece.

8. A capillary heating element for XRD and XAS tests according to claim 1, characterized in that, The temperature measuring device is a thermal resistor or a thermocouple.

9. A capillary heating system for XRD and XAS tests, characterized in that, It includes a heating element and a temperature controller. The heating element is a capillary heating element for XRD and XAS tests as described in any one of claims 1 - 8. The heating wire and the temperature measuring device are both connected to the temperature controller.

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