阅读说明：本技术 用于天然气水合物x射线衍射仪测试的样品托及其应用 (Sample holder for natural gas hydrate X-ray diffractometer test and application thereof ) 是由 张少鸿 苏秋成 于 2020-12-16 设计创作，主要内容包括：本发明公开了一种用于天然气水合物X射线衍射仪测试的样品托,包括基座,所述基座中间开设有用于盛装样品的凹槽,所述基座的前边缘及两侧边缘分别设有用于契合衍射仪样品座支架的导轨,所述基座的底部中间开有适于衍射仪控温附件热电偶的贯穿孔,所述贯穿孔将所述基座的前后侧贯穿；所述凹槽底部设有狭缝,所述狭缝与所述贯穿孔连通。本装置将天然气水合物样品在液氮中装填到样品托凹槽,在液氮保护中将装满样品的样品托迅速转移装上已经预冷到目标低温的X射线衍射仪低温样品台进行测试；减少对样品的破坏和污染,提高了天然气水合物X射线衍射仪测试的准确性。(The invention discloses a sample holder for testing a natural gas hydrate X-ray diffractometer, which comprises a base, wherein a groove for containing a sample is formed in the middle of the base, guide rails for fitting with a sample holder bracket of the diffractometer are respectively arranged on the front edge and the two side edges of the base, a through hole suitable for a thermocouple of a temperature control accessory of the diffractometer is formed in the middle of the bottom of the base, and the front side and the rear side of the base are penetrated through by the through hole; the bottom of the groove is provided with a slit which is communicated with the through hole. The device fills a natural gas hydrate sample into a sample holder groove in liquid nitrogen, and quickly transfers the sample holder filled with the sample to a low-temperature sample table of an X-ray diffractometer precooled to a target low temperature for testing under the protection of the liquid nitrogen; the damage and pollution to the sample are reduced, and the accuracy of the natural gas hydrate X-ray diffractometer is improved.)

1. A sample support for testing a natural gas hydrate X-ray diffractometer is characterized in that: the diffraction instrument temperature control accessory thermocouple device comprises a base, wherein a groove for containing a sample is formed in the middle of the base, guide rails for fitting a diffraction instrument sample seat support are respectively arranged on the front edge and the two side edges of the base, a through hole suitable for a diffraction instrument temperature control accessory thermocouple is formed in the middle of the bottom of the base, and the front side and the rear side of the base are penetrated through by the through hole; the bottom of the groove is provided with a slit which is communicated with the through hole.

2. The sample holder for testing of a gas hydrate X-ray diffractometer according to claim 1, wherein: the groove is of a cuboid structure, and the cross section of the groove is rectangular.

3. The sample holder for testing of a gas hydrate X-ray diffractometer according to claim 2, wherein: the length range of the groove is 12-18 mm, the width range is 10-15 mm, and the depth range is 0.8-3 mm.

4. The sample holder for testing of a gas hydrate X-ray diffractometer according to claim 1, wherein: the width range of the base is 21-22 mm, and the length range of the base is 23-24 mm; the thickness range of the guide rail is 1.5-2.5 mm, and the width range is 1-2 mm.

5. The sample holder for testing of a gas hydrate X-ray diffractometer according to claim 1, wherein: the width of the slit is less than 1 mm.

6. The sample holder for testing of a gas hydrate X-ray diffractometer according to claim 1, wherein: the base material of the base is copper or copper alloy, and the surface of the base is plated with nickel.

7. The sample holder for testing of a gas hydrate X-ray diffractometer according to claim 1, wherein: one end of the through hole penetrates through the front side wall of the groove, and the upper side of the guide rail at the front edge of the base is cut into an arc-shaped groove by the through hole.

8. Use of a sample holder according to any one of claims 1 to 7 in a gas hydrate X-ray diffractometer test.

9. The application of claim 8, further comprising: (1) placing the sample holder in liquid nitrogen to realize the filling of the sample in the liquid nitrogen; (2) and (4) supporting the sample into a diffractometer to realize the test of the natural gas hydrate X-ray diffractometer protected by liquid nitrogen.

Technical Field

The invention relates to the technical field of X-ray diffractometer testing, in particular to a sample holder for testing a natural gas hydrate X-ray diffractometer and application thereof.

Background

X-ray diffraction (XRD) is an analytical technique for studying the internal structure (i.e., internal atomic arrangement) of a crystal using diffraction generated when X-rays are irradiated to a crystalline (or some amorphous) substance. When a substance (crystal or amorphous) is subjected to diffraction analysis, the substance is irradiated by X-rays to generate diffraction phenomena of different degrees, and the composition, crystal form, intramolecular bonding mode, molecular configuration, conformation and the like of the substance determine the substance to generate a special diffraction pattern. The X-ray diffraction method has the advantages of no damage to the sample, no pollution, rapidness, high measurement precision, capability of obtaining a large amount of information related to the integrity of the crystal and the like. Therefore, X-ray diffraction analysis, a modern scientific method for analyzing the structure and composition of materials, has been widely used in various scientific researches and productions. The X-ray diffractometer mainly comprises an X-ray generator (an X-ray tube), a goniometer, an X-ray detector, a computer control processing system and other accessories.

Natural gas hydrates are formed from gas molecules (including hydrocarbons and CO)₂、H₂S, etc.) and water molecules in a high-pressure, low-temperature environment, mainly having three crystal structures of type i (cubic crystal structure), type ii (rhombic crystal structure) and type H (hexagonal crystal structure). The research on the structural characteristics and the change rule of the hydrate has important significance for understanding the formation mechanism, the micro-dynamics, the phase state transformation, the identification of hydrate samples and the like of the hydrate. X-ray diffraction analysis is the primary method of studying the phase and crystal structure of a substance. The technology is applied to the research of the natural gas hydrate, can not only accurately obtain the important information of the structure type, the lattice parameter and the like of the hydrate, but also observe the micro-dynamic process of the generation and decomposition of the hydrate. Therefore, the structure type of the hydrate crystal can be judged by accurately measuring the lattice parameter of the hydrate crystal through an XRD technology, and the technology is applied to the identification of natural gas hydrate samples drilled in oceans and frozen soil regions abroad and obtains structure information. In addition, by measuring the change of the hydrate crystal parameters generated under different conditions, the structure transformation and the influence rule of the hydrate can be researched, and the research shows that the composition of the mixed gas, the volume and the diameter of the guest molecule, the temperature and the like all affect the hydrate crystal parameters and the structure. By XRD in-situ technology under high pressure environment, diffraction peaks in the process of generating and decomposing hydrate can be measuredThe research shows that the generation/decomposition of the hydrate is mainly divided into two stages, namely a rapid generation/decomposition process on the surface of gas and liquid (solid) and a diffusion process of gas molecules in the liquid (solid), and the reaction speed is controlled in the latter stage.

At present, the X-ray diffractometer testing technology is generally used at home and abroad as a main method for solving basic scientific problems of structure type identification, lattice parameter measurement and the like of hydrates. However, the sample holder configured by the existing X-ray diffractometer is mainly designed for material testing, most materials are in a normal temperature state, the sample is easy to mill and process under the normal temperature condition, and the natural gas hydrate is formed under the conditions of high pressure and low temperature, can only exist at low temperature, is decomposed at normal temperature, is damaged and polluted, and is generally stored in liquid nitrogen. Therefore, the natural gas hydrate cannot be ground and processed at normal temperature and subjected to sample loading test like the material, and the natural gas hydrate must be ground and processed in liquid nitrogen, but is difficult to be ground due to easy decomposition, and the sample loading test can be carried out only by reducing the sample stage (support) to a lower temperature. The existing technical scheme for testing the X-ray diffractometer can only load samples at normal temperature and in the air environment, and the amount of the loaded samples is small. The sample loading method can lead the low-temperature natural gas hydrate to be partially decomposed under the influence of normal-temperature air, the sample amount is small, and meanwhile, the low-temperature natural gas hydrate is polluted by condensation of moisture in the air, and the test result is influenced.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a sample holder for testing a natural gas hydrate X-ray diffractometer and application thereof.

The invention is realized by the following technical scheme: a sample holder for testing a gas hydrate X-ray diffractometer comprises a base, wherein a groove for containing a sample is formed in the middle of the base, guide rails for fitting with a diffractometer sample holder support are respectively arranged on the front edge and the two side edges of the base, a through hole suitable for a temperature control accessory thermocouple of the diffractometer is formed in the middle of the bottom of the base, and the front side and the rear side of the base are penetrated through by the through hole; the bottom of the groove is provided with a slit which is communicated with the through hole.

The guide rails on the front edge and the two side edges of the base can realize that the sample is supported and placed on the sample holder bracket of the diffractometer; the through holes are arranged for placing a thermocouple of a temperature control accessory of the diffractometer; the slit communicated with the through hole can enable the sample to be in direct contact with the thermocouple, and the accuracy of temperature monitoring is improved.

The groove is of a cuboid structure, and the cross section of the groove is rectangular.

The length range of the groove is 12-18 mm, the width range is 10-15 mm, and the depth range is 0.8-3 mm.

The width range of the base is 21-22 mm, and the length range of the base is 23-24 mm; the thickness range of the guide rail is 1.5-2.5 mm, and the width range is 1-2 mm.

The width of the slit is less than 1 mm.

The base material of the base is copper or copper alloy, and the surface of the base is plated with nickel.

One end of the through hole penetrates through the front side wall of the groove, and the upper side of the guide rail at the front edge of the base is cut into an arc-shaped groove by the through hole.

According to a second aspect of the present invention there is provided the use of a sample holder for gas hydrate X-ray diffractometer testing.

The application further comprises: placing the sample holder in liquid nitrogen to realize the filling of the sample in the liquid nitrogen; and (4) supporting the sample into a diffractometer to realize the test of the natural gas hydrate X-ray diffractometer protected by liquid nitrogen.

Compared with the prior art, the invention has the advantages that: the device fills a natural gas hydrate sample into a sample holder groove in liquid nitrogen, and quickly transfers the sample holder filled with the sample to a low-temperature sample table of an X-ray diffractometer precooled to a target low temperature for testing under the protection of the liquid nitrogen; the damage and pollution to the sample are reduced, and the accuracy of the natural gas hydrate X-ray diffractometer is improved.

Drawings

FIG. 1 is a schematic structural diagram of an embodiment of the present invention;

FIG. 2 is a top view of an embodiment of the present invention;

FIG. 3 is a front view of an embodiment of the present invention;

FIG. 4 is a left side view of an embodiment of the present invention;

fig. 5 is a transverse cross-sectional view of an embodiment of the present invention.

The reference numerals in the drawings mean: 1. a groove; 2. a slit; 3. a front edge; 4. two side edges; 5. a through hole; 6. an arc-shaped groove.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and detailed description.

Examples

Referring to fig. 1 to 5, a sample holder for testing a gas hydrate X-ray diffractometer comprises a base, wherein a groove 1 for containing a sample is formed in the middle of the base, guide rails for fitting with a sample holder bracket of the diffractometer are respectively arranged on the front edge 3 and the two side edges 4 of the base, a through hole 5 suitable for a temperature-controlled accessory thermocouple of the diffractometer is formed in the middle of the bottom of the base, and the front side and the rear side of the base are penetrated through by the through hole 5; the bottom of the groove 1 is provided with a slit 2, and the slit 2 is communicated with a through hole 5.

The guide rails at the front edge 3 and the two side edges 4 of the base can realize that a sample is supported and placed on a sample seat bracket of the diffractometer; the through holes 5 are arranged for placing a thermocouple of a temperature control accessory of the diffractometer; the slit communicated with the through hole can enable the sample to be in direct contact with the thermocouple, and the accuracy of temperature monitoring is improved.

The groove 1 is of a cuboid structure, and the cross section of the groove is rectangular.

The length range of the groove 1 is 12-18 mm, the width range is 10-15 mm, and the depth range is 0.8-3 mm.

The width range of the base is 21-22 mm, and the length range of the base is 23-24 mm; the thickness range of the guide rail is 1.5-2.5 mm, and the width range is 1-2 mm.

The width of the slit 2 is less than 1 mm.

The base material of the base is copper or copper alloy, the surface of which is plated with nickel, and the base material can also be other suitable materials with good heat conduction and stable chemical properties.

One end of the through hole 5 penetrates through the front side wall of the groove 1, and the through hole 5 cuts the upper side of the guide rail of the front edge 3 of the base to form an arc-shaped groove 6.

According to a second aspect of the present invention there is provided the use of a sample holder for gas hydrate X-ray diffractometer testing.

The application further comprises: placing the sample holder in liquid nitrogen to realize the filling of the sample in the liquid nitrogen; the sample is held in a diffractometer to realize the test of the natural gas hydrate X-ray diffractometer with liquid nitrogen protection

According to a preferred embodiment of the present invention, the steps of performing the gas hydrate X-ray diffractometer test using the above sample tray are as follows:

the method comprises the following steps: placing the sample in liquid nitrogen, and fully cooling the sample;

step two: suitably milling a natural gas hydrate sample stored in liquid nitrogen;

step three: the ground natural gas hydrate sample is filled into the groove 1 of the sample holder in liquid nitrogen, and then the sample holder filled with the sample and with the liquid nitrogen is quickly transferred to a low-temperature sample stage of an X-ray diffractometer which is precooled to the target low temperature for testing.

The above detailed description is specific to possible embodiments of the present invention, and the embodiments are not intended to limit the scope of the present invention, and all equivalent implementations or modifications that do not depart from the scope of the present invention are intended to be included within the scope of the present invention.