CN2809635Y

CN2809635Y - EXAFS equipment based on monolithic X-ray focusing lens

Info

Publication number: CN2809635Y
Application number: CN 200520008746
Authority: CN
Inventors: 丁训良; 孙天希; 刘志国
Original assignee: Beijing Normal University
Current assignee: Beijing Normal University
Priority date: 2005-03-22
Filing date: 2005-03-22
Publication date: 2006-08-23
Anticipated expiration: 2015-03-22

Abstract

The utility model relates to an EXAFS spectrometer on the basis of an integrally convergent X-ray lens and a position sensitive detector, which is composed of an X-ray source, a sample, a plane monochromator, a position sensitive detection system and the integrally convergent X-ray lens between the X-ray source and the sample. A core component of the utility model which can be used for carrying out structural analysis on the sample is the integrally convergent X-ray lens placed between a light source and the sample. The utility model is characterized in that the reasonable combination of the integrally convergent X-ray lens and the position sensitive detection system achieves the EXAFS analysis of spatial discrimination and time resolution on the sample. Simultaneously, since the integrally convergent X-ray lens has high magnification, the utility model can make use of a low power light source to carry out the EXAFS analysis. Additionally, the EXAFS spectrometer has the advantages of simple structure and low fabrication cost.

Description

Assemble the EXAFS spectrometer of x-ray lens based on integral body

Technical field:

The utility model relates to a kind of whole EXAFS (ExtendedX-ray Absorption Fine Structure) spectrometer of assembling x-ray lens and position sensitive detector that uses.It is still not have the whole novel scientific instrument of assembling x-ray lens of use that commodity are released in the world.Can study the structure of crystalline state material and amorphous substance with it.

Background technology:

Existing space is differentiated the EXAFS spectrometer, great majority are by utilizing aperture to limit X-ray beam, as everyone knows, differentiate for the implementation space, the diameter dimension of aperture certainly will be very little, and this just greatly reduces the X ray intensity of beating on sample, thereby caused measuring the long time of EXAFS spectrum needs, so that influence the quality that EXAFS composes, so when differentiating the EXAFS analysis, must use high strength X ray light source with the aperture implementation space; Existing time resolution EXAFS spectrometer needs high-intensity X ray light source equally; Sample is carried out simultaneously the EXAFS spectrometer of time resolution and spatial discrimination, requirement to the X ray intensity of light source is just higher, so, existing time resolution EXAFS spectrometer, spatial discrimination EXAFS spectrometer and the EXAFS spectrometer that carries out time resolution and spatial discrimination simultaneously all are subjected to the restriction of the intensity of light source, have influenced popularizing and promoting of they.

The utility model content:

The purpose of this utility model is to provide a kind of novel scientific instrument that can carry out time resolution and spatial discrimination EXAFS analysis to material.

The purpose of this utility model realizes by following measure: this spectrometer comprises X source, whole x-ray lens, monochromator and the position sensitive detection system assembled.Its characteristics are: be added with the whole x-ray lens of assembling between light source and monochromator, owing to whole assemble X-ray that x-ray lens can will disperse in wide-angle macro-energy scope to be converged to diameter be little focal spot of tens of microns, when sample is placed on the focal spot position place, may detect the information in tens of micrometer ranges, so the EXAFS that the utility model can the implementation space be differentiated analyzes.Because the whole very high enlargement factor that has of assembling x-ray lens, simultaneously, owing to assemble the X-ray beam that x-ray lens is assembled through integral body, just dispersed out through behind the focal spot position, so put suitable monochromator in the focal spot back, according to the Bragg diffraction law as can be known, the X ray continuous spectrum of dispersing is after the monochromator effect, the locus difference of the X ray of different-energy, at this moment, put position sensitive detector, can measure the X ray intensity of each energy point in certain energy range simultaneously in the monochromator back, thereby shortened the note spectrum time greatly, analyzed so the utility model can be realized time-resolved EXAFS.

Whole to assemble x-ray lens be fritted glass solid single, that do not have support component, and its inside is to be that 5～10 microns kapillary constitutes by many internal diameters.These lens are approximately the combination of space quafric curve section, quafric curve section or the combination of quafric curve section and straight-line segment along the profile bus of length and the bus of X-ray conduit profile and the axis of X-ray conduit, and the radial variations of the profile bus of the bus of lens and X-ray conduit is symmetrical for the central axis of lens.X-ray can be transferred to the other end by means of full the emission from an end of conduit in capillary vessel, changed the transmission direction of X-ray in the transmission course.Because lens have the said structure characteristics, thus the direction of propagation of X-ray can be changed, thus can in the macro-energy scope, assemble X-ray.The whole x-ray lens of assembling has 10 ³The enlargement factor of the order of magnitude

The import cross section of whole convergence x-ray lens and outlet size are less than lens full-size.Entrance point cross section and X-ray conduit are respectively regular hexagon and circle in the cross section perpendicular to the lens center axis direction.The entrance point cross section is identical with the endpiece cross sectional shape, and the X-ray conduit is the function in space along the sectional dimension perpendicular to the central line of lens direction, and the closer to two ends, sectional dimension is more little.

Describe in the parameter of whole convergence x-ray lens performance, wherein, outlet focal length, inlet focal length, focal spot size, enlargement factor, transfer efficiency are all relevant with energy with equivalent distances, the whole size of assembling length, inlet diameter, outlet diameter and the maximum cross-section of x-ray lens all is because of the special design of the specific (special) requirements of EXAFS analysis and research, constitute lens internal diameter capillaceous and number and draw material that lens adopt also because of research project require different.

The utility model has following advantage compared with the prior art:

1. because the whole X-ray of assembling x-ray lens can converging and diverging, so the utility model adopts the whole x-ray lens of assembling the power density of beating the X-ray on sample can be improved thousands of times, thereby has shortened the note spectrum time, has improved the quality of EXAFS spectrum.

2. because the whole x-ray lens of assembling can be converged to the X-ray of dispersing diameter at little focal spot of tens of microns,, can carry out EXAFS to tiny sampler simultaneously and analyze so this spectrometer can be analyzed the EXAFS that differentiate the sample implementation space.

3. because convergent lens has very high enlargement factor, simultaneously, after the X-ray that whole convergence x-ray lens will be dispersed is converged to little focal spot, the X-ray bundle scatter again, this is convenient to adopt the position sensitive detection system to measure the X ray intensity of each energy point in certain energy range simultaneously, thereby shortened the note spectrum time, so the utility model can carry out time-resolved EXAFS and analyze under low power sources.

4. because the utility model has adopted whole convergence x-ray lens, make the energy resolution of this EXAFS spectrometer no longer be subjected to the influence of dimension of light source, be convenient to improve the energy resolution of spectrometer.

5. because the whole combination of assembling x-ray lens and position sensitive detector makes this spectrometer can carry out the EXAFS analysis of time resolution and spatial discrimination to sample simultaneously.

6. because the whole x-ray lens of assembling does not have support, compact conformation so the utility model is simple in structure, cheap, is convenient to popularize and promote the use of.

Description of drawings:

Below in conjunction with accompanying drawing the utility model is described in further detail.

Fig. 1 is a structural representation of assembling the EXAFS spectrometer of x-ray lens based on integral body;

Fig. 2 is a whole synoptic diagram of assembling x-ray lens in the utility model;

Fig. 3 is a whole sectional view of assembling the edge of x-ray lens perpendicular to central line of lens among Fig. 2.

Embodiment:

Referring to accompanying drawing 1 and Fig. 2, the utility model is made up of X source 1, whole x-ray lens 2, sample 3, monochromator 4 and the position sensitive detection system 5 assembled.

X-ray 6 from X source emission is collected and is assembled by whole x-ray lens, and being converged to from the X-ray 7 of lens outgoing scatter again behind little focal spot 8 of tens of microns forms the light beam of dispersing 9.9 dozens of continuous X-ray bundles in certain energy range are separated by monochromator according to Bragg's law after on the monochromator, have formed different-energy (as the λ among Fig. 1 ₁, λ ₂And λ ₃Deng) space distribution of X-ray, after being surveyed by the position sensitive detection system by the X-ray of the different-energy of space distribution, form the x-ray spectroscopy of high energy resolution, can compose based on these and can carry out EXAFS to sample and analyze.

Referring to Fig. 2, the whole inlet end diameter D that assembles x-ray lens _InWith endpiece diameter D _OutDiameter D with its maximum cross-section _MaxCompare, the former is less; The whole x-ray lens inlet focal distance f of assembling ₂With the outlet focal distance f ₁Can equate also can not wait; The length l of lens is decided according to experiment condition; The capture angle ω to light source of lens _CaptureDifferent and different along with lens arrangement and dimension of light source; Angle of divergence ω after the X-ray bundle that integral body convergence x-ray lens is assembled leaves focal spot _DivergenceVariation with lens arrangement changes.The intensity rate of the X ray that enters the X ray light intensity of lens inlet end and come out from lens is defined as the transfer efficiency of lens, and the structure of the transfer efficiency of lens and energy, lens is relevant with the factors such as size of light source.The lens enlargement factor is defined as: when lens being arranged and not having lens, and the ratio of the power density of somewhere X-ray, it is relevant with the structure and the energy of lens, and it is also relevant with the locus simultaneously.The focal spot size of lens, inlet focal length, outlet focal length, capture angle are all relevant with the structure and the energy of lens with the angle of divergence.

Referring to Fig. 3, the lens edge is a regular hexagon perpendicular to the profile of the xsect of central line of lens direction, and the profile of every capillary xsect is circular.Kapillary closely is arranged in together, if the number of plies at a middle capillary place is defined as 1, then from inside to outside the number capillaceous on each layer is 6 (n-1), and wherein n＞1 is the number of plies, internal diameter size capillaceous can be identical also can be inequality.

Provide the example of whole X-ray convergent lens below: lens 04-3-27-3 has 205060 X-ray conduits and constitutes, on direction cross section perpendicular to central line of lens, the internal diameter size of every capillary is identical, and on the maximum cross section, the internal diameter of every capillary is about 6 microns; The length of lens is 70mm, the inlet end of lens and the diameter of endpiece are respectively 5mm and 3mm, at the 17.4keV energy point, lens inlets focal length, outlet focal length, transfer efficiency, focused spot diameter, enlargement factor and the angle of divergence, be respectively 78mm, 13mm, 1%, 27 μ m, 3000 and 2 °.

Claims

1. the EXAFS spectrometer based on integral body convergence x-ray lens comprises X source, sample, lane monochromator, position sensitive detection system, it is characterized in that: this spectrometer also is included in and is added with a whole x-ray lens of assembling between X source and the sample.

2. EXAFS spectrometer according to claim 1 is characterized in that: the whole x-ray lens of assembling is a fritted glass solid single, that not have support, in many capillaries are arranged; These lens are approximately the combination of space quafric curve section, quafric curve section or the combination of quafric curve section and straight-line segment along the profile bus of length and the profile bus of X-ray conduit and the axis of X-ray conduit, and the radial variations of the profile bus of the bus of lens and X-ray conduit is symmetrical for the central axis of lens.

3. EXAFS spectrometer according to claim 1 is characterized in that: whole assemble x-ray lens to have diameter be little focal spot of tens of microns.

4. EXAFS spectrometer according to claim 1 is characterized in that: the whole x-ray lens of assembling has the enlargement factor of 103 orders of magnitude.

5. EXAFS spectrometer according to claim 1 is characterized in that: whole entrance point cross section and the X-ray conduit of assembling x-ray lens is respectively regular hexagon and circle in the cross section perpendicular to the lens center axis direction; The edge is perpendicular to the central line of lens direction, and the closer to two ends, the sectional dimension of X-ray conduit is more little.