DM2400type

MEDXRFLight element spectrometer

satisfyNational V, NationalVIUltra low for automotive gasoline and dieselStesting requirements

Ultra low detection limit（300s）：

Si: 0.7ppm，P: 0.4ppm，

S: 0.15ppm，Cl: 0.08ppm

use

monochromeExcitation energy dispersionXX-ray fluorescence(MEDXRF)analysis technique

High diffraction efficiencyLogarithmic spiralrotational hyperboloid(LSDCC)intraocular lens

High count rate(2Mcps)And resolution(123eV)ofSDDdetector

reasonablekV、mA、Target material combinationMicro focal spotThin beryllium windowXX-ray tube

Compliant with standards:

GB/T 11140

ISO20884

ASTM D2622

ASTM D7039

ASTM D7220

ASTM D7757

ASTM D7536

ISO 15597

ASTM D6481

overview

DM2400Type monochrome excitation energy dispersionXX-ray fluorescence light element（Si、P、S、Cl）Spectrometer,abbreviationDM2400typeMEDXRFLight element spectrometer,Our company has been collecting data for decadesXThe research experience of fluorescence spectrometer, in the company's existingDMseriesXFluorescence sulfur analyzerXFluorescence multi-element analyzer, wavelength dispersion analyzerXOur company has developed and launched the first monochromatic excitation spectrometer based on X-ray fluorescence multi-channel spectrometer and other technologiesXRFa spectrometer.It adopts the following technologies and devices,Make use of50WOptical tube spectrometerDM2400With excellent reproducibility and stability, ultra-low detection limit, modern technology has been fully utilized.

Monochromatic excitation energy dispersionXX-ray fluorescence(MEDXRF)analysis technique

XDetection limit of X-ray fluorescence spectrometerLOD（limit ofdetection3）It refers to the standard deviation of the instrument background signal generated by the blank matrix

The corresponding amount of multiple value, namely:1（

）In the formula,_RbCount the intensity of the background (background),NGiven the concentrationCThe counting intensity of low concentration samples,T1To measure time. From formula（）It can be seen that the detection limit and sensitivity（_N-Rb）/CInversely proportional to the background_Rb

The square root is proportional. To reduce the detection limit under a certain measurement time, it is necessary to increase sensitivity and/or reduce background.1.pictureMEDXRF

Schematic diagram of analytical technologytraditionXRFRegardless of whether it isEDXRFstillWDXRFOne of the main reasons why it is not possible to achieve a lower detection limit isX

The scattering of continuous bremsstrahlung radiation in the emission spectrum of the X-ray tube results in a higher background of continuous scattering in the fluorescence spectrum.Monochromatic excitation energy dispersionXX-ray fluorescence(MonochromaticExcitation Beam Energy Dispersive X-Ray Fluorescence)Analytical techniques refer to the use of optical devices toXMonochromatization of the emission spectrum of the X-ray tube greatly reduces the continuous scattering background of the fluorescence spectrum, while minimizing or even increasing the required excitation if possibleXThe intensity of monochromatic lines or narrow energy bands of radiation greatly reduces the detection limit. Compared to traditional1EDXRF2ReducedtoAn order of magnitude, compared to high power (such as4kwof

WDXRF2.It's also much lower.pictureThe sample

XRF

spectrogramHigh diffraction efficiency logarithmic spiral rotation point-to-point focusing artificial monochromatic crystalsupportXThere are many methods for monochromatizing the emission spectrum of a X-ray tube, including filter method, secondary target method, and diffraction method. And the hyperbolic diffraction crystal in diffraction methodDCC（

DoublyCurvedCrystals）It is the most monochromatic and efficient.

Diffraction must satisfy Bragg2Law:

nλ=2dsinθ2（）That is to say, the wavelength of the radiation emitted from the source must satisfy（）The formula is diffracted, so it has excellent monochromatization. Also, due toDCCBeing able to focus the point source, it has a large collection solid angle, resulting in extremely high efficiency. In addition, focusing can also make the light spot irradiated onto the sample very small, thereby enabling small area semiconductor detectorsSi-PINperhapsSDD

Most samples can accept fluorescence rays from smaller surfaces, which means3.DCCIt also improved the detection efficiency.picture

The solid line isXThe emission spectrum of the X-ray tube,Red represents the classicsLSDCC

Characteristics of monochromatizationXX-ray incidence spectrumDCCAccording to its surface, it can be further divided into semi focusing（Johann）, Full Focus（Johansson）And logarithmic spiral（Logarithmic Spiral）Wait. Among them, semi focusing only partially satisfies the diffraction conditions, so it is necessary to undergo semi focusingDCCCharacteristics of monochromatizationXThe X-ray incidence spectrum is the worst. Full focusing is a point-to-point focusing that fully satisfies the diffraction conditions. But fully focusedDCCThe manufacturing process is extremely complex, and besides bending, it must have a grinding processRThe process of curved surfaces, such as natural crystalsSi，GeWaiting is very brittle and extremely difficult to grind, while artificial crystals cannot be ground. In addition, natural crystals are usually in a very narrow spectral rangespread outshootXRay. Causing target material characteristics

XOnly a portion of the radiation is diffracted, resulting in a low integral diffraction rate.DM24002The logarithmic spiral rotating dual surface artificial crystal usedDM30LIt is a collection of our company's technical elitesA patented product developed through years of diligent research and development.Logarithmic spiralDCCIt also fully satisfies the diffraction conditions. Although the focusing is not point-to-point, but point to point, due to the small size of this surface, it is generally only2mmLeft and right, so it can be considered point-to-point.3It uses10DM

Artificial crystal, whose integral diffraction rate is the same as that of natural crystals4. arriveSo the efficiency of this crystal is currently the highest in the world. In addition, it only needs to be bent without grinding or splicing, making it easy to manufacture.

pictureLSDCCPrinciple diagram of point-to-point focusinghigh resolution(123eV)High count rate

(2Mcps'SDDdetectorXThere are many types of radiation detectors, including proportional counter tubes,8Si-PIN8Detector and silicon drift detectorSDDWait. The resolution of the detector is represented by the half width of the universal peak, and the net count of the universal peak is independent of the half width. However, its background count is proportional to the half width, so the higher the resolution, the lower the detection limit. The half width of a proportional counter tube is the same as that of a semiconductor detectorAbout times, so the detection limit is highAbout square root times.Si-PINResolution ratio

SDD0It is slightly inferior and its resolution drops sharply at high counting rates, soSDDIt is the best detector.DM240Adopting GermanyKETEKProduced by the companyVITUS H20 CUBE(superlative)SDD²Detector with a resolution less than123eVEffective detection area

20mm5. Counting rate2Mcps

.pictureSilicon Drift DetectorSDDreasonablekV、

mAMicro focal spot thin beryllium window with target material combinationXX-ray tubeStimulating the sampleXThe closer the radiation energy is to the absorption limit of the element being analyzed, the higher the excitation efficiency.DM30LCrystals only diffractXHigh intensity characteristics in the emission spectrum of the X-ray tubeXRadiation is emitted by the target material. So a reasonable selection of target materials can achieve the highest excitation efficiency.DM2400Standard type due to its measurability

ClThe following elements are selected, thereforeAgAs a target material.After selecting the target materialXWhen the maximum power of the ray tube is constant, such as50WReasonable high pressure of light tube（kV）And current（mA）The combination can achieve maximum excitation efficiency. Due to the use of point-to-point focusing, it is necessary to use micro focal spotsXLight tube. Due to the characteristics of the target material

XThe radiation energy is very low, so a thin beryllium window must be usedXRadiation tube.DM2400use50WMicro focal spot thin beryllium windowXRadiation tube, standard type selectionAgTarget and target

kV6. 、mAMake a reasonable combination.

picture

Micro focal spot thin beryllium window7XX-ray tubecalibrationUsing known amountsindividualcontainSi、P、7S

、7. ClCalibrate the instrument with the sample and obtain the graphThe work curve.picturecontainSi、P、

S、Cl0.999Sample working curveThe correlation coefficients of these working curvesγ

All greater than

, indicatingDM2400The linear error of the spectrometer is extremely small.

accuracy2. In order to further test the accuracy of the analysis, five samples of diesel and light oil with different sulfur contents were prepared, and each sample was loaded into two different sample cups for analysisSAccuracy test:

diesel oil2gasolinegasolinegasolineoutsideThe obtained concentration results are shown（ppm）, as well as comparison with nominal values. These results indicate that at low concentration levels

DM2400

The spectrometer can achieveSExcellent accuracy.accuracyFor the three types, each containing seven different ones

Sample Cup1.Conduct gasoline sample testingSRepetitive test:outsideSGasoline sampleS

RSD8.6%4%2.69%These results indicate that at low concentration levels

DM2400

The spectrometer can achieveSExcellent repeatability.characteristic

Quickly and simultaneously–Simultaneously measure the required elementsQuick analysis, usually providing content results within a few seconds.Low detection limit–Adopting advanced technology

MEDXRFTechnology,LSDCCCore technology, reaching the global minimum detection limit. Has extremely high reproducibility and reproducibility.long term stability–Adopting variable gain digital multi-channel,have

PHAAutomatic adjustment, drift correction, deviation correction and other functions，Has excellent long-term stability.

Environmental protection and energy saving–Radiation protection meets exemption requirements.During analysis, there is no contact or damage to the sample, no pollution, no need for chemical reagents, and no need for combustion.Easy to use–Touch screen operation. The sample is directly loaded into the sample cup, and after placing it in the instrument, simply press the button

[start]Just press the key, truly achieving one click operation.high reliability

–Integrated design,High degree of integration, strong environmental adaptability, strong anti-interference ability, and high reliability

Additives, lubricants containing additives, and products produced during the refining process.

It is also applicable to any material in various industriesClSimultaneously measure the following elements1Specification3Note: If the user considers the standard typeDM2400If the requirements cannot be met, you can raise them with our company, and we will try our best to meet the user's requirements. If a lower detection limit is required, our company can remove the crystal fromBlock increase toBlock to reduce detection limit as before1/1.73If measurement is requiredFThe following elements with atomic numbers can be selected by our company for usersAP3.3The entrance windowSDDIf the user wants to be highSMeasurement of trace amounts under the substrateAlandSiOur company can provide standard models