High-pressure vessel experimental device for neutron scattering
阅读说明:本技术 一种用于中子散射的高压容器实验装置 (High-pressure vessel experimental device for neutron scattering ) 是由 袁宝 胡海韬 白波 黄志强 林权 张绍英 童欣 于 2019-11-29 设计创作,主要内容包括:本发明公开了一种用于中子散射的高压容器实验装置,包括:筒体、密封单元、锁定单元、加热单元、中子吸收层以及四刀光阑,筒体的侧壁上设置有用于中子入射和散射的窗口,筒体内设置有放置样品管的腔体,密封单元用于将样品管密封在腔体内,锁定单元用于将样品管锁定在筒体内,中子吸收层设置在加热单元的外侧,四刀光阑设置在中子吸收层的侧面。本申请提供的上述方案,锁定装置上的设置可保证加载力的加载及维持恒定;窗口的设置保证了中子入射和散射的无阻碍通过,提高了中子透过率,加热单元的设置保证了样品达到所需要的高温环境,四刀光阑和中子吸收层的设置,分别减小了中子束斑和吸收杂散中子,降低了样品衍射谱本底。(The invention discloses a high-pressure vessel experimental device for neutron scattering, which comprises: the device comprises a cylinder, a sealing unit, a locking unit, a heating unit, a neutron absorption layer and a four-knife diaphragm, wherein a window used for neutron incidence and scattering is arranged on the side wall of the cylinder, a cavity used for placing a sample tube is arranged in the cylinder, the sealing unit is used for sealing the sample tube in the cavity, the locking unit is used for locking the sample tube in the cylinder, the neutron absorption layer is arranged on the outer side of the heating unit, and the four-knife diaphragm is arranged on the side face of the neutron absorption layer. According to the scheme provided by the application, the locking device can ensure the loading of the loading force and maintain the loading force to be constant; the setting of window has guaranteed that the unobstructed of neutron incidence and scattering passes through, has improved neutron transmissivity, and the sample has been guaranteed to reach required high temperature environment to the setting of heating element, and the setting of four-knife diaphragm and neutron absorbing layer has reduced neutron beam spot respectively and has absorbed stray neutron, has reduced sample diffraction spectrum background.)
1. A high pressure vessel experimental apparatus for neutron scattering, comprising: barrel, sealing element, locking unit, heating unit, neutron absorbed layer and four-knife diaphragm, be provided with the window that is used for neutron incidence and scattering on the lateral wall of barrel, be provided with the cavity of placing the sample cell in the barrel, the position of cavity with the position of window is to corresponding, sealing unit be used for with the sample cell is sealed in the cavity, locking unit be used for with the sample cell locking is in the barrel, heating unit sets up the lateral wall of barrel is used for giving sample heating in the sample cell, the neutron absorbed layer sets up the outside of heating unit for absorb stray neutron, four-knife diaphragm sets up the side of neutron absorbed layer.
2. The high-pressure vessel experimental apparatus for neutron scattering of claim 1, wherein a ceramic cavity is disposed in the cylinder, the sample tube is disposed in the ceramic cavity, a wedge-shaped ring is surrounded by the ceramic cavity, and the ceramic cavity and the wedge-shaped ring are in interference fit.
3. The high-pressure vessel experimental apparatus for neutron scattering according to claim 2, wherein the locking unit comprises a lower locking nut disposed at a lower end of the cylinder, a lower piston disposed between the lower locking nut and the ceramic cavity, a locking ring disposed at an upper end of the cylinder, and an upper piston disposed between the locking ring and the ceramic cavity.
4. The apparatus of claim 3, wherein the locking unit further comprises a lower pad disposed between the lower piston and the lower locknut, an upper pad disposed at the open end of the barrel, and an upper locknut disposed between the upper locknut and the upper piston.
5. The high-pressure vessel testing apparatus for neutron scattering of claim 4, further comprising a stress beam disposed on the upper locknut.
6. The high pressure vessel experiment device for neutron scattering of claim 3, wherein the sealing unit comprises a lower sealing ring, an upper sealing ring and a sample tube cap, the lower sealing ring is disposed between the lower piston and the sample tube, the sample tube cap is disposed between the upper piston and the sample tube, and the upper sealing ring is disposed between the sample tube cap and the sample tube.
7. The high pressure vessel experimental apparatus for neutron scattering of claim 1, wherein the heating unit comprises a heater blanket disposed on an outside wall of the barrel.
8. The high-pressure vessel experimental facility for neutron scattering of claim 7, wherein the heating blanket comprises a resistance heating wire, a thermometer and an insulating layer from inside to outside in sequence, and the resistance heating wire is closely attached to the outer side wall of the cylinder.
9. The high pressure vessel testing apparatus for neutron scattering of claim 7, wherein the four-blade diaphragm comprises a plurality of pieces of neutron absorbing devices disposed outside of the heater blanket.
Technical Field
The invention relates to the fields of neutron scattering and high-pressure science and technology, in particular to a high-pressure container experimental device for neutron scattering.
Background
The interaction between the neutrons and the atomic nucleus of the substance has strong penetration capability and can penetrate through the thick wall of the high-pressure container, so that the environment for loading the high-pressure sample in the neutron scattering experiment is more convenient. The high-pressure environment is very important for the research of materials, and can shorten the distance between atoms in the materials, influence the overlapping of electron clouds, change the valence of elements and the like, and cause great changes to the structure and physical properties of the materials. Some changes of the material are reversible, the material can return to the state before the experiment after pressure relief, the characteristics of the material when pressurized cannot be obtained, and the in-situ high-pressure neutron scattering can represent the structure and physical properties of the material when high pressure is loaded. Therefore, the development of in-situ high-pressure neutron scattering research has important significance on the disciplines of material science, geophysical science, condensed state physics, chemistry, energy, environment and the like.
At present, most of in-situ high-pressure neutron scattering experiments are carried out by using metal high-pressure containers, the containers are processed by high-strength alloy materials, most of the high-strength alloy components contain cobalt element, have magnetism, and are small in sample volume and extremely low in neutron transmittance (less than 10%). The defects of the alloy material respectively have great influence on personal safety of experimenters, accuracy of experimental results, experimental efficiency, background and the like.
Disclosure of Invention
In view of the above technical problems, the present invention provides a high pressure vessel experimental apparatus for neutron scattering.
The invention provides a high-pressure vessel experimental device for neutron scattering, which comprises: barrel, sealing element, locking unit, heating unit, neutron absorbed layer and four-knife diaphragm, be provided with the window that is used for neutron incidence and scattering on the lateral wall of barrel, be provided with the cavity of placing the sample cell in the barrel, the position of cavity with the position of window is to corresponding, sealing unit be used for with the sample cell is sealed in the cavity, locking unit be used for with the sample cell locking is in the barrel, heating unit sets up the lateral wall of barrel is used for giving sample heating in the sample cell, the neutron absorbed layer sets up the outside of heating unit for absorb stray neutron, four-knife diaphragm sets up the side of neutron absorbed layer.
In one embodiment, a ceramic cavity is arranged in the cylinder, the sample tube is arranged in the ceramic cavity, a wedge-shaped ring is arranged around the ceramic cavity, and the ceramic cavity is in interference fit with the wedge-shaped ring.
In one embodiment, the locking unit includes a lower locking nut disposed at a lower end of the cylinder, a lower piston disposed between the lower locking nut and the ceramic chamber, a locking ring disposed at an upper end of the cylinder, and an upper piston disposed between the locking ring and the ceramic chamber.
In one embodiment, the locking unit further comprises a lower pad disposed between the lower piston and the lower locknut, an upper pad disposed at the open end of the cylinder, and an upper locknut disposed between the upper locknut and the upper piston.
In one embodiment, the locking device further comprises a force applying rod, and the force applying rod is arranged on the upper locking nut.
In one embodiment, the sealing unit comprises a lower sealing ring, an upper sealing ring and a sample tube cap, the lower sealing ring is arranged between the lower piston and the sample tube, the sample tube cap is arranged between the upper piston and the sample tube, and the upper sealing ring is arranged between the sample tube cap and the sample tube.
In one embodiment, the heating unit comprises a heating blanket disposed on an outer sidewall of the cartridge.
In one embodiment, the heating blanket comprises a heating resistance wire, a thermometer and an insulating layer which are sequentially arranged from inside to outside, and the heating resistance wire is tightly attached to the outer side wall of the barrel.
In one embodiment, the four-blade aperture includes a plurality of neutron absorbing devices disposed outside of the heater blanket.
According to the high-pressure vessel experimental device for neutron scattering provided by the embodiment, the locking nut and the pressurizing rod which are arranged on the locking device can ensure the loading of the loading force and keep the loading force constant; the arrangement of the window ensures that neutrons enter and scatter without obstruction, the neutron transmittance is improved, the interference of neutron diffraction peaks on sample signals is reduced, the background of neutron diffraction spectra is reduced, and the arrangement of the heating unit ensures that the sample reaches the required high-temperature environment. The arrangement of the four-knife diaphragm and the neutron absorption layer respectively reduces the neutron beam spot and absorbs stray neutrons, and the background of the diffraction spectrum of the sample is reduced.
Drawings
FIG. 1 is a cross-sectional view of an experimental apparatus for a high-pressure vessel for neutron scattering according to an embodiment of the present invention;
FIG. 2 is an enlarged partial schematic view of FIG. 1;
fig. 3 is a schematic view of the overall structure of fig. 1.
Detailed Description
The present invention will be described in further detail with reference to the following detailed description and accompanying drawings. Wherein like elements in different embodiments are numbered with like associated elements. In the following description, numerous details are set forth in order to provide a better understanding of the present application. However, those skilled in the art will readily recognize that some of the features may be omitted or replaced with other elements, materials, methods in different instances. In some instances, certain operations related to the present application have not been shown or described in detail in order to avoid obscuring the core of the present application from excessive description, and it is not necessary for those skilled in the art to describe these operations in detail, so that they may be fully understood from the description in the specification and the general knowledge in the art.
Furthermore, the features, operations, or characteristics described in the specification may be combined in any suitable manner to form various embodiments. Also, the various steps or actions in the method descriptions may be transposed or transposed in order, as will be apparent to one of ordinary skill in the art. Thus, the various sequences in the specification and drawings are for the purpose of describing certain embodiments only and are not intended to imply a required sequence unless otherwise indicated where such sequence must be followed.
The numbering of the components as such, e.g., "first", "second", etc., is used herein only to distinguish the objects as described, and does not have any sequential or technical meaning. The term "connected" and "coupled" when used in this application, unless otherwise indicated, includes both direct and indirect connections (couplings).
As shown in fig. 1 to 3, in an embodiment of the present invention, there is provided a high pressure vessel experimental apparatus for neutron scattering, including: the device comprises a
Specifically, a
Further, the
The sealing unit is used for sealing the sample and the pressure transmission medium, and also ensures the constancy of the high-pressure environment of the sample and the pressure limit. When in assembly, the
The locking unit is used for fixing the sample loading force and comprises an
The
The heating blanket is used for heating the high-pressure container, so that indirect heating of the sample is realized, and the heating mode is indirectly heating. The heating blanket comprises a heating resistance wire, a thermometer and a heat-insulating layer; the heating wire is arranged in the inner layer of the heating blanket and is in close contact with the outer wall of the locking device, so that good heat conduction can be realized; the cylinder body of the high-pressure container is made of beryllium copper alloy, so that the high-pressure container has excellent heat conducting performance and realizes heat transfer to a sample. The heat-insulating layer is arranged on the outer layer of the heating blanket to prevent the heat of the high-pressure container from dissipating; the thermometer is arranged between the heating resistance wire and the heat preservation layer. The temperature rise, the accurate temperature control and the temperature measurement of the high-pressure container can be well realized through the electrical plug connected to the heating blanket, and finally the temperature index of 150 ℃ can be realized.
The four-knife diaphragm is used for controlling the incident neutron beam spot, the beam spot size required by the experiment is realized by adjusting the size of the diaphragm, other neutrons are effectively absorbed, and neutrons outside the range of the sample are prevented from irradiating other materials to cause pollution to the sample signal. The four-knife diaphragm can well reduce the background of neutron scattering experimental data of a sample. The four-blade diaphragm comprises four neutron absorption devices, and the movement of the four neutron absorption devices can be controlled by a motor or manually to reach the size of a neutron range to be controlled; the neutron absorption device is made of one of boron carbide, boron nitride, boron-containing polyethylene, cadmium, gadolinium oxide and the like.
The neutron absorption layer is used for absorbing stray neutrons, so that the background of neutron scattering experimental data is reduced. The neutron absorption layer is arranged on the outermost layer of the high-pressure container, and the full coverage of other areas except the neutron incidence, emission and scattering windows is realized. The neutron absorption layer is a material which can be well formed, and can be one of cadmium, gadolinium, boron-containing polyethylene, gadolinium oxide coating and the like.
The specific working process of the high-pressure vessel experimental device for neutron scattering provided by the embodiment is as follows:
firstly, assembling a ceramic cavity: embedding the ceramic cavity into the conical holes of the two wedge-shaped rings, wherein the ceramic cavity, the conical holes of the two wedge-shaped rings and the ceramic cavity are coaxial, and the contact surfaces are ensured to be tightly attached; the ceramic core is placed in a tablet press to be pressed for interference fit, and the loading force is 30 tons, so that the ceramic cavity generates prestress, and larger pressure can be resisted; after the wedge-shaped ring is assembled, the bottom surface of the wedge-shaped ring is processed to be smooth, the distance between the bottom surface of the wedge-shaped ring and the bottom surface of the ceramic cavity is 2 mm, and the ceramic cavity is in a concave shape. Secondly, placing the assembled ceramic cavity into a cylinder, placing a lower cushion block into a groove of a lower locking nut, and installing the lower locking nut at the bottom of the cylinder; a lower piston, a lower sealing ring, a sample tube (containing a sample and a pressure transmission medium), an upper sealing ring, a sample tube cap, an upper piston and an upper cushion block are sequentially placed from the top of the cylinder body, and the upper piston is embedded into a groove on the bottom surface of the upper cushion block. Thirdly, screwing the locking ring into the cylinder until the locking ring tightly presses the ceramic cavity; and (4) installing a locking nut, inserting the stress application rod into a central hole of the locking nut, and enabling the bottom surface to be in contact with the upper surface of the upper cushion block. And finally, wrapping a heating blanket and a neutron absorption layer on the outer wall of the high-pressure container, and installing a four-blade diaphragm at the neutron incident port. To this end, the assembly of the entire high-pressure vessel is completed.
Placing the assembled high-pressure container in a tablet press for pressurization, gradually increasing the loading force, and screwing an upper locking nut until the loading force is loaded to a target pressure before the loading force is increased each time; after pressurization is completed, the plug of the heating blanket is connected with a power supply, and the temperature can be loaded to the target temperature; and adjusting the four-knife diaphragm to limit the size of a neutron incident light spot. And transferring the high-pressure container to a neutron scattering spectrometer, and carrying out in-situ high-pressure neutron scattering experimental test on the sample.
The present invention has been described in terms of specific examples, which are provided to aid understanding of the invention and are not intended to be limiting. For a person skilled in the art to which the invention pertains, several simple deductions, modifications or substitutions may be made according to the idea of the invention.
- 上一篇:一种医用注射器针头装配设备
- 下一篇:一种检测细菌数量的方法