Analysis of common problems in direct reading spectrometer

1. How does the Spike M9 direct reading spectrometer replace the spring of the fixed electrode?

The fixed electrode is not a spring. Generally, there is a locking screw at the bottom of the excitation table to fix it. Unscrew the 4 copper screws, remove the green insulating block and the white insulating block, and mark the order. .

2. The software of ARL3460 direct reading spectrometer OXSAS will not prompt that the standardization has expired on the day after each standardization, but the next day it indicates that the standardization has expired. What is the reason?

Open the OXSAS software, click on F12 and click on the sample plus sign in the drift calibration sample. Check the gap time and set zero.

3. How much does it affect the excitation by adjusting the distance of the excitation electrode?

The change in pole pitch is 0.5 mm, and the result is greatly affected because the intensity varies greatly.

4. Why are different bases and excitation stations different?

Different excitation stages are used to reduce cross-contamination caused by sample analysis and affect the analysis results. In order to reduce cross-contamination, different excitation stages are used respectively.

5, direct reading spectrum upper and lower electrodes connected to the sample is to conduct electricity?

Generally only one is the electrode, which is inside the excitation hole, or the following one, the electrode will have a high voltage when it is discharged, and will not be exposed to the place where it can be touched! The above is the pressure bar, not the electrode, the main function is to fix the sample, mechanical, and pneumatic. The pressure bar usually has a wire to be connected, mainly to detect whether there is a sample, no sample is detected, it is not allowed to be excited, and it is also for safety.

6. What elements of direct reading spectrum analysis are prone to interference?

It is meaningful to discuss the interference to be combined with the specific material. It is also related to the resolution of the instrument. For example, B in steel generally uses the B 182.64 nm line, and there is a line of S 182.625 nm next to it. The line is relatively close. For instruments with low resolution, the two lines cannot be separated, and the interference is very serious. However, for high resolution instruments or high-order lines, the interference of S to B is not lost. So obvious.

7. In the direct reading spectrometer, the electrode will not be brushed. What direction will the analysis result develop?

If it is the same brand of product, no brush electrode is no problem. If the products of different grades are contaminated without brushing the electrode analysis results, the results will be very different. It is recommended to brush the electrode after finishing a sample.

8. The tungsten electrode used for direct reading spectrometer, copper electrode and silver electrode are used for component analysis or material screening. What is the basis for their choice?

There are many kinds of excitation electrodes for direct reading spectral analysis, such as carbon, copper, aluminum, tungsten, and silver. Different excitation electrodes are selected according to the analysis method and the analysis object. The principle of choice is to better analyze the precision. The element being analyzed should not be in the excitation electrode material. Electrical erosion is small. In the photoelectric spectrum analysis, it is used continuously several times in order to increase the analysis speed. When silver is used as the excitation electrode, it is easy to obtain silver with high purity. Since silver has a high melting point, heat capacity and thermal conductivity are good; and it has good electrical conductivity and corrosion resistance. In the steel analysis, the general steel does not contain silver, so the precision of the analysis using silver as the excitation electrode is relatively high. The silver electrode tip must be turned into a cone and the top end is at a 90' angle. However, with the excitation light source of unidirectional discharge, the excitation electrode is easily eroded during discharge. Therefore, the tungsten rod is used as the excitation electrode, and the tungsten electrode is generally not easy to be long-pointed, and generally can be used continuously for hundreds of times without cleaning the electrode once.

9. Is the direct reading spectrometer a good straight space or is it better to fill the argon chamber?

In fact, purely from the data and precision, the five qualified 9-purity argon-type instruments and vacuum-type instruments are no different. Their differences are mainly reflected in:

(1) Vacuum type instrument: The production cost of the instrument manufacturer is high, and the cost of the whole machine is high. why? Because there is a vacuum design, there must be a leak rate guarantee, there must be a pump, a valve, and even anti-return oil, anti-oil mist. Is it troublesome? Quite troublesome. But users buy it back and use it to save money and worry.

(2) Argon type instrument: The production cost of the instrument manufacturer is low, and the cost of the instrument is low. why? Because there is no vacuum design, there is no leakage rate guarantee, no pump, no valve, just blow argon into the instrument. Jane is not simple? Quite simple. But the user does not worry about using it after buying it. Argon gas is a few hundred bottles a bottle, and the argon gas fee for several years seems not cheap. If the excitation data is not good, it will be said that the purity of argon is not enough. To buy a purifier, change the purification tube. Even because of problems with argon, the light chamber is contaminated and the instrument is directly scrapped.

10. Does the ARL4460 reading spectrometer use a tungsten rod as an electrode to measure tungsten?

The tungsten element can be measured because the light source is a unidirectional discharge, and the unidirectional discharge only excites the sample, and the electrode itself is not excited, thus substantially eliminating the influence of the tungsten electrode on the sample excitation.

11. What is the background correction intensity in the direct reading spectrometer?

The actual measured spectral intensity includes the intensity of the spectral line itself and the spectral background. As the name suggests, the intensity of the background correction is the intensity of the spectral line after subtracting the spectral background. This is the intensity of the true reactive element content, and the analysis will be more accurate. Instruments using photomultiplier tubes generally approximate the spectral background by adding a background channel, and the CCD instrument is more accurate in terms of the spectral background.

12. What is the standard strength in the direct reading spectrometer?

Compared with the factory, the light intensity will inevitably change. The normalized intensity is the normalized coefficient to convert the current background correction intensity to the factory strength, so that the model can be taken into the factory to calculate the sample content. For example, the factory-standardized sample has a strength of 500, and the current intensity is 400, and the normalization coefficient is 1.25. When testing a sample with a strength of 450, the normalized intensity is 450*1.25=562.5. The actual situation is more complicated than this. Two standardized samples are used to calculate the normalization coefficient. The normalization coefficient also includes the two parts of multiplication and addition.

13. What is the concentration ratio in the Spike direct reading spectrometer?

For example, a sample, the content of Mn is 1%, the content of Fe is 90%, then 1% / 90% = 1 / 90 = 0.01111 = 1.11% 1.111% is the percentage ratio of Mn to Fe! That is the concentration ratio. Just use %, it is called the percentage ratio or percentage ratio. For another example: Mn content of 1%, Fe content of 50%, then 1 / 50 = 0.02 = 2%, only use the percentage ratio to use the internal standard, in order to calculate the Fe content, in order to calculate the Mn content !

14. What should I do if the instrument vacuum pump does not start?

(1) Whether the power supply voltage is too low and the starting torque is insufficient.

(2) The lubricating oil in the pump is dry and the cylinder is stuck.

(3) In the low temperature area, the oil in the pump is frozen and condensed, which is difficult to start.

(4) The protection system works and cannot be started.

15. Which of the direct reading spectra of steel samples and the accuracy of the icp spectrometer is high?

The ICP spectrometer is a sample that dissolves and samples, which is of course more uniform, and the performance index is better than direct reading, but some elements in the actual analysis are still not very good, such as aluminum. The comparison effect in the laboratory is very bad, especially when the acid is dissolved and the acid is insoluble. In addition, if Ca is very demanding on the sample processing process, it will be very different if it is not too small, and B will be inferior in low content (less than 20 PPM) analysis;

Direct reading spectra are generally analyzed using primary or secondary spectra. Spectral interference is relatively large, and analysis is greatly affected by the matrix. However, interference correction technology has overcome this shortcoming. Solid samples are directly analyzed and do not require pretreatment. The analysis speed is fast, the data is accurate, and the pre-furnace analysis is indispensable. As far as accuracy is concerned, the individual believes that in general, it is necessary to believe in the number of ICP spectra. When there is a conflict, it is best to find an authoritative third party to verify the error to facilitate the correction.

16. What is the role of the ARL direct reading spectrometer fatigue lamp?

(1) The fatigue lamp is located between the grating and the exit slit. When the fatigue lamp is turned on, the fatigue lamp emits a mixed wavelength of light emitted by the analog excitation stage, which replaces the spectrum emitted by each element during excitation. If the operating voltage of the fatigue lamp is stable, it can be understood that the emitted light is constant.

(2) Determine whether the optical path is abnormal. When the fatigue lamp is turned on, the light emitted by the fatigue lamp is irradiated onto the Loren circle and passed through the optical channel to the PMT to help determine whether the exit slit and the mirror are normal.

(3) Judging whether the circuit is abnormal or not, testing the fatigue lamp data, compared with the data at the time of installation, can help determine whether the photomultiplier tube, negative high voltage, high voltage attenuation, IVFC channel board, ICS board and other components are working properly.

(4) Under certain conditions, it is sometimes possible to check whether the temperature and vacuum of the spectral chamber are normal.

When the sample is excited, the fatigue lamp is extinguished. When the pulse is not excited, the fatigue lamp is always on. If the PMT is working in the dark for a long time, it will suddenly receive light from the light source. The light intensity measured at the beginning is not stable. The average user may not find this problem during use, but if the interval between the two measurements is long and the negative high voltage is relatively high, the effect is relatively obvious. If the fatigue light in the spectroscopic room has been illuminating the PMT, this problem can be solved. Of course, the instrument for the CCD detector does not have the above mentioned problems.

17. The laboratory temperature is at 15 °C. Does the temperature have a great influence on the analysis results of the direct reading spectrometer?

The influence of temperature on the instrument is divided into two types: internal temperature of the instrument and ambient temperature of the instrument. The internal temperature of the instrument is displayed by software, as long as it is stable for a long time and meets the requirements. However, the internal temperature is often affected by the external temperature, so the external constant temperature is very important. The outdoor cold in the north of winter often affects the internal temperature of the laboratory, so it is important to keep the laboratory temperature constant and meet certain requirements.

18, ARL4460 direct reading spectrometer lens connected to two lines, what is the role?

The two wires heat the lens to prevent the lens from getting wet and affect the analysis results.

19, ARL4460 direct reading spectrometer lens to the spark between the pipe has a valve (a short metal bar), what is the role?

The metal rod is called "shutter shutter". It blocks most of the light during the pre-combustion phase, preventing excessive light from entering the optical system and protecting the optical device. In a sense, it can also prevent the lens from being contaminated.

20. What does SSE mean in a spark direct reading spectrometer?

SSE should be “Single Spark Evaluation” used to calculate acid and acid insolubles.

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