First, excellent features:
1. High performance with glass atomizer and robustness of metal atomizer.
2. Use a special restrictive flow inlet tube that is not easily blocked.
3. Sensitivity reaches the highest level of flame atomic absorption method, which is more than double the national standard.
4. Acid resistant (except hydrofluoric acid), type 3 is resistant to hydrofluoric acid.
5. The user is free of adjustment and the excellent performance is unchanged for a long time.
6. Type 2 is adjustable for injection volume in the range of 0-10ml.
7. Type 3 is a special type of hydrofluoric acid resistant atomizer.
8. If you need to use organic solvents, please make a statement when ordering.
Second, the structure: (see the schematic below)
The solution to be tested is sucked into the inner tube of the coaxial glass atomizer, and the outer tube is connected to the compressed air. The spout is provided with a removable impact ball cap (not interchangeable between different atomizers), and the glass atomizer is fixed in stainless steel protection. Inside the sleeve, the shape of the stainless steel is compatible with the atomizer seat of each model. The inner tube is plugged into a special inner diameter polyethylene restricting flow inlet tube, or the stainless steel tube is inserted - the silicone tube - the polyethylene restricting flow inlet tube (not easy to fall off) , silicone tube is not resistant to organic solvents).
Third, the installation:
1. If the inner diameter of the atomizer seat can pass through the atomizer that has been covered with the impact ball cap, the atomizer that has been adjusted to the optimal spray state can be directly inserted without hitting the spray chamber and hitting the ball end.
2. If the atomizing seat cannot pass through the atomizer that has the impact ball cap, the end of the fog chamber can be removed, the atomizer that has removed the impact ball cap is inserted into the atomizer seat and fixed, and the impact ball is placed. After the cap is pressed to the optimal spray state, the end of the mist chamber is loaded back to the mist chamber and fastened.
3. The adjustment of the optimal spray state: suction water (lifting amount should be greater than 4ml/min), the impact ball cap will be pressed against the spout and rotate back and forth, while observing the state of the sprayed mist flow, the best state is: 1 Spray forward, each side is symmetrical, the angle is larger; or 2% of the plane is spread out and sprayed forward, and each side needs to be symmetrical. Special attention: the connecting rod that hits the ball cap after adjustment should be within 45 degrees to the left and right.
Fourth, the working parameters:
1. The compressed air pressure is 0.2Mpa, (or the pressure set by the instrument manufacturer). The air flow rate is 10-11L/min (measured from the outlet under normal temperature and normal pressure). The air flow meter is calibrated under normal temperature and normal pressure. If the air flow meter calibrated at normal temperature and pressure is connected in series before the atomizer inlet pipe, the flow rate is measured under non-standard pressure (0.2 MPa), and the reading is reduced to about 5.5 "L/min". The production plant is connected in this way, this reading can not be used for the calculation of stoichiometry (the same situation acetylene flow can not be used for stoichiometric calculation). The manufacturer or user changes the standard working pressure of the atomizer to 0.2MPa, analytical performance Changed. No auxiliary combustion gas is required. If the instrument is originally equipped with combustion gas, it should be closed. Laughing gas can also be used in the same atomizer (safe use and air/nitrogen automatic switching valves are available).
2. The amount of sample solution lifted: based on the measurement of copper to the maximum absorbance, about 4-6ml / min, this lift is also applicable to other elements requiring low-temperature atomization, for high-temperature atomized elements (such as calcium) should Reduce the amount of lifting, otherwise too much aerosol enters the flame and lowers the flame temperature, resulting in lower atomization efficiency, that is, the sensitivity of the measurement is reduced, and the interference of other elements is increased. If the concentration of the measured element is not particularly low, Not necessarily all measured under optimal conditions, the current limiting inlet tube may not be replaced. Reducing the length of the glass capillary at the rear of the inlet tube reduces the amount of lift, and vice versa.
3. If the type 2 atomizer is used, the lifting amount can be continuously adjusted, and the best lifting amount can be found by measuring the elements, that is, using the standard liquid with a larger concentration (the absorbance is about 0.3A), continuously increasing or decreasing the lifting amount. Use the maximum absorbance (maximum of 6ml/min), which is more convenient than replacing the inlet tube with type 1.
4. Acetylene flow rate: continuously change the flow of acetylene with the standard solution with absorbance of about 0.3A, and select the flow with maximum absorption. Note: The absorption of the rich flame itself is also very large, especially for short wavelength measurement. Two different concentrations of the standard solution were measured, and the absorbance was subtracted (excluding the flame absorption), and the condition with a large difference was selected.
5. The position of the burner (upper and lower, front and back and corner), also use the standard solution with absorbance of 0.3-0.4A, and change the position condition to select the condition with large absorbance. The effective light cannot absorb the large internal flame (white light) through the flame, and the front and back and the corner position which have a great influence on the absorbance should be small each time. It can also be used with a front sharpening tip, a straight 1mm diameter metal rod is inserted vertically in the middle of the burner slit, adjusted to the maximum light blocking position, and then at the end of the slit, the rotary burner is adjusted to the maximum light blocking position.
Five, performance check:
Using air/acetylene flame, 2μg/ml copper is measured, the absorbance is better than 0.40A, and the relative standard deviation (RSD) should be less than 0.8% (related to host stability).
Note: (1) The main unit and the air supply should be stable. (2) The beam should pass directly above the burner slot, and the distance between the optical axis and the slot is about 6-8 mm.
(3) The burner should be heated for more than 15 minutes.
Sixth, fault handling and maintenance:
1. The restricted flow inlet tube is clogged, usually at the inlet, can be removed with a finger, or blown back with compressed air, or reversely filled with a syringe.
2. When the sample solution is inhaled, a series of bubbles will form in the tube. The resistance will be large to stop the inhalation. Use the finger to bounce the inlet tube to make the bubble suck away. Normally, the bubble can be sucked away by the syringe.
3. The inner tube of the nebulizer is blocked: it is often blocked near the spout, remove the impact ball cap, and use the compressed air or syringe to reverse the water to flush the blockage. Never use the wire æ…, otherwise the atomizer will be damaged. The company does not assume warranty responsibility.
4. The airflow passage of the nozzle is blocked. The impact ball cap can be removed and flushed with reverse airflow or water. It can also be flushed with a syringe.
5. The inner tube or air flow channel of the nozzle is blocked by organic matter, accumulated dust or dry salt. The impact ball cap can be removed and inserted into the sulfuric acid-potassium dichromate solution heated to the smoke for a few seconds. (Note: Do not allow the washing liquid to enter the inside of the atomizer). If it is used for more than half a year or if the air flow is reduced, it should be treated as such.
6. After each use, spray with distilled water for 2-3 minutes (no tap water is allowed to prevent the solution from clogging).
7. The working room temperature should not be lower than 10 °C, otherwise the cooling effect of the spout can make the solution freeze and block the atomizer.
8. If the host has a channel to assist the gas, the auxiliary gas should be shut off. Otherwise, the gas that is not involved in the spray can make the sensitivity low. The excessive gas flow will not only consume more gas, or even flame.
9. The ball caps are not interchangeable between all nebulizers, otherwise the sensitivity is greatly reduced.
Seven, two type atomizer schematic
1. The restriction injection tube (suction tube) can be used to control the injection volume and replace the injection tube.
2. Atomizer metal sleeve (used to connect with the host)
3. Sealing rubber ring
4. Nebulizer glass inner tube (inner capillary)
5. Impact ball cap and seal
6. The atomizer spray impacts the ball (including the impact ball struts) and is detachable for adjusting the spray state. When the adjustment is completed, the impact ball struts must be within 45 degrees of the left and right angles.
7. Impact ball strut
8. Atomizer glass outer tube
9. Intake struts for connecting compressed air and locking the intake manifold.
10. Type 2 nebulizer injection volume adjustment screw. The -1 type does not have this part.
11. Type 1 and Type 2 atomizers are equipped with atomic absorption of each type. The glass parts are basically the same except that the metal sleeve and the struts are different.
See for details:
Electrolyte Analyzer,Electrolyte Analyser,Electrolyte Machine,Medica Electrolyte Analyzer
ZSL MED , https://www.zslmed.com