Spectrophotometer 752XIAN

The 722 Spectrophotometer instrument is suitable for the visible spectrum.

The content of substances in the region is quantitatively analyzed, which can be widely used in basic laboratories of factories, schools, agriculture, food, biochemistry, environmental protection, medical and health units. The steps are as follows:

1. Adjust the sensitivity knob to "1" gear (minimum signal amplification).

2. Turn on the power supply, the indicator light is on, the selection switch is set to "T", and the wavelength is adjusted to the wavelength for testing. The instrument is warmed up for 20 min.

3. Open the sample chamber (the light door will close automatically) and adjust the light transmittance.

Zero knob so that the numbers are displayed as. (adjust the 100% t knob), close the sample chamber lid, and place the cuvette rack in distilled water.

Correct the position so that the photocell receives light, and adjust the light transmittance 100% knob to make the digital display.

If it is not displayed, the multiple of microcurrent amplification can be increased appropriately. (Increase the number of gears of sensitivity, and at the same time repeat (3) adjust the "0" position of the transmittance of the instrument), but try to make the magnification use at a low level. In this way, the instrument will have higher stability.

4. After preheating, adjust the position of "0" and "100%" of light transmittance several times in a row, and the instrument can be measured after stabilization.

Notes:

This instrument is suitable for working in a stable laboratory environment, and the installation conditions are:

Ambient temperature: 5° 35°

Ambient humidity: 85%.

Power supply voltage: 220V 10% 50Hz

The rear side of the main unit is more than 20 cm from the wall.

Avoid direct sunlight, avoid vibrations, avoid dust, avoid corrosive substances.

Dear, I am glad to answer for you: How to use 721g visible spectrophotometer A1Turn on the power supply, turn on the instrument switch, lift the lid of the dark box in the sample chamber, and warm up for 10 minutes.

2.Set the sensitivity switch to "1" (if the zero adjuster cannot be set to "0", you need to use a higher setting.) ） 3.

Turn the wavelength selector according to the desired wavelength. 4.Pour the blank solution and the measuring solution into the cuvette 3 4 respectively, wipe the outer wall with a mirror paper, put it into the sample chamber, and align the blank tube with the optical path.

5.Adjust the zero regulator with the camera obscura lid open so that the readingdial pointer points to t=0. 6.

Cover the lid of the camera obscura, adjust the "100" to adjust the slapper, so that the t = 100 of the blank tube, and gradually pull out the sample slide rod after the pointer is stable, read out the optical density value of the measuring tube respectively, and record. 7.After the color comparison is completed, turn off the power, take out the cuvette and wash it, and wipe the sample chamber with a soft cloth or soft paper.

Basic principle The ultraviolet and blue-violet light emitted by the high-pressure mercury lamp or xenon lamp are irradiated into the sample cell by a filter, and the fluorescent substances in the sample are excited to fluoresce, and the fluorescence is filtered and reflected, accepted by the photomultiplier tube, and then displayed in the form of a graph or number. The generation of material fluorescence is changed to an excited state after the molecules of substances in the ground state absorb the excited light under normal conditions, and these molecules in the excited state are unstable, and in the process of returning to the ground state, a part of the energy is released in the form of light, so as to produce fluorescence Different substances have different characteristics due to the different molecular structures, and the distribution of the energy levels of the excited states has their own different characteristics, which is reflected in the fluorescence as various substances have their characteristic fluorescence excitation and emission spectra; , so it can be determined by the difference in fluorescence excitation and emission spectra....

Unico (Shanghai).752 spectrophotometerThe working principle is similar to that of infrared spectroscopy and Raman spectroscopy, and a certain frequency of ultraviolet-visible light is used to irradiate the substance to be detected, causing an electronic transition in the substance, so as to show the spectral change caused by the change of absorption wavelength, and record the spectral change to form analysis data.

752 spectrophotometerVisible light exhibits different colors due to different wavelengths, and these wavelengths present different colors within a certain range of light called monochromatic light. The white light emitted by the sun or tungsten filament is composite light, which is a mixture of various monochromatic lights. Using a prism, white light can be divided into various monochromatic lights arranged in wavelength order, i.e., red, orange, yellow, green, cyan, blue, violet, etc., which is the spectrum.

Colored substance solutions can selectively absorb a part of the energy of visible light and appear different colors, while some colorless substances can characteristically choose the energy of ultraviolet or infrared light. Substances absorb some wavelengths of light emitted by the light source to form an absorption spectrum, because the molecular structure of the substance is different, the absorption capacity of light is different, so each substance has a specific absorption spectrum, and under certain conditions its absorption degree is proportional to the concentration of the substance, spectrophotometry is the use of this absorption characteristics of the substance to carry out qualitative or quantitative analysis of different substances.

752 spectrophotometerPrecautions for use:

1) The slit width of the selected instrument should be less than the half width of the absorption band of the test sample, otherwise the measured absorbance value will be low, and the selection of the slit width should be based on the fact that the absorption of the test sample will not increase when the slit width is reduced, and for most of the tested varieties, 2nm slit width can be used.

2) Take out the desiccant in the sample chamber before starting, and it is forbidden to open the sample chamber cover during the instrument self-test.

3) The absorption pool must be clean and used in pairing. Measuring flasks and pipettes should be calibrated and washed before use. The solution in the cuvette should not be overfilled at the height of the dish to prevent the liquid from spilling and corroding the instrument.

The cuvette should be kept clean during the measurement, and the droplets on the pool wall should be wiped dry with mirror paper, and the translucent surface should not be pinched by hand. For the determination of ultraviolet wavelength, quartz cuvettes are used. Note that the absorption cell is placed in the same direction as the sample chamber.

After use, rinse with solvent or water, dry and dust-proof.

4) After the experiment, pour out the solution in the cuvette, then rinse the cuvette with distilled water or organic solvent until it is clean, and dry it upside down. Turn off the power and put the desiccant into the sample chamber, cover with a dust cover, and register for use.

5) The test sample is marked with the test substance and the configured concentration. In the test, the solvent of the test sample should be used as a blank control: the wavelength specified by the instrument or the specified absorption peak should be automatically scanned and measured, and the absorption should be measured to check whether the position of the absorption peak of the test sample is correct.

The 752 spectrophotometer is an instrument used to detect the absorption and transmission of light from a sample, and the 336nm wavelength UV lamp is a commonly used detection wavelength in this instrument. If the 336 nm wavelength is found to be unstable when using a 752 spectrophotometer, there may be several reasons:1

Aging of light sources: Light sources in spectrophotometers, such as deuterium lamps and tungsten lamps, will gradually deteriorate over time, resulting in reduced or unstable light intensity. Workaround:

Replace the deuterium or tungsten lamp that has deteriorated to restore the stability of the 336nm wavelength. 2.Improper adjustment of the instrument:

When using a spectrophotometer, the instrument needs to be calibrated and adjusted to ensure a stable and accurate signal. If it is not adjusted properly, it may affect the detection results at the 336nm wavelength. Workaround:

Check the spectrophotometer's manual for proper adjustment procedures to restore stability at the 336nm wavelength. 3.Sample Contamination:

When using a spectrophotometer to test a sample, there may be sample contamination, such as precipitation, impurities, etc., which may affect the transmission of light and the absorption of the defeat, resulting in unstable detection results. Solution: Treat or purify the sample to remove contaminants and ensure that the sample is pure and free of impurities.

Hello dear<>

The 752 spectrophotometer is unstable at 336nm wavelength, which may be due to the following reasons:1The bulb is aged or damaged.

The 752 spectrophotometer uses the same lamp as the light source for all wavelengths, and if the bulb ages or is damaged, it can cause unstable light intensity at certain wavelengths, causing fluctuations in readings. Bulbs need to be inspected and replaced if necessary. 2.

Semiconductor detector aging. The 752 spectrophotometer uses multiple numerical semiconductor detectors to detect light of different wavelengths. If the performance of the detector corresponding to the 336nm wavelength is degraded or deteriorated, the wavelength reading will be inaccurate or unstable.

This wavelength detector needs to be replaced. 3.The grating or filter is damaged.

Damage or contamination of the grating or 336nm filter can cause light at that wavelength to be unable to be effectively separated or transmitted, resulting in low or unstable readings. The optics need to be inspected and cleaned or replaced. 4.

Wavelength calibration bias. If the wavelength calibration of the 752 spectrophotometer is off, the actual detection wavelength of 336nm will deviate from the theoretical value, resulting in inaccurate or fluctuating readings. Full-spectrum wavelength calibration is required to correct deviations.

5.Cell issues. If the position of the sample in the cell is not constant, or if the cell wall is dirty, it will cause the irradiation of the 336nm Guangshan Song Road to the sample to be obstructed or biased, causing the reading to fluctuate.

The sample cell needs to be cleaned to ensure that the sample position is fixed. The most common of these possible causes are lamp aging, detector aging, and wavelength calibration deviations. If the bulb and detector are normal, it is recommended to perform a full-spectrum wavelength calibration of the spectrophotometer.

If the 336 nm wavelength reading remains unstable after calibration, the possibility of damage to the optics or cell issues is considered. Hopefully, this information will help you analyze and resolve the problem of unstable 336nm wavelength readings from the 752 spectrophotometer.

If your beam's spectrophotometer is showing instability at 336 wavelengths, there could be a few reasons for this:1Light source issues:

There may be problems with the light source of the spectrophotometer, such as an aging or unstable bulb. This may lead to unstable pin intensity at wavelength 336, which can affect the accuracy of the measurement results. You can try replacing the light source or performing maintenance and calibration of the light source.

2.Grating problem: Spectrophotometers use gratings for wavelength selection, which can also lead to unstable measurements at wavelengths of 336 if the grating is damaged or unstable.

You can check the encoder for damage or need to be cleaned and make sure it is properly installed in the instrument. 3.Signal Detection Issues:

The spectrophotometer's signal detector may be faulty or inaccurate, resulting in erratic readings at 336 wavelengths. You can try calibrating or replacing the signal detector to fix the problem. 4.

Calibration issues: Spectrophotometers need to be calibrated regularly to ensure accurate measurements. If your instrument is not calibrated for a long time or is not calibrated correctly, it can cause instability at wavelength 336.

Please ensure that the calibration is carried out in accordance with the instructions for use of the instrument, and that the calibration material is used correctly and that the head bucket is stored.

Summary. Second, the use of 722 spectrophotometer.

1. Turn the sensitivity knob to "1".

(minimum signal amplification).

2. Turn on the power supply, the indicator light is on, the selection switch is set to "T", and the wavelength is adjusted to the wavelength for testing. The instrument is warmed up for 20 min.

3. Open the sample chamber (the light door closes automatically), adjust the zero knob of light transmittance, and make the number display as. (Adjust 100% t-spin.)

752N ultraviolet spectrophotometer new machine adjustment.

2. The use of 722 spectrophotometer 1. Adjust the sensitivity knob to "1" gear (the signal magnification is the smallest). 2. Turn on the power supply, the indicator light is on, select the switch to "T", and adjust the wavelength to the wavelength for testing. The instrument is warmed up for 20 min.

3. Open the test chamber (the light door is automatically closed), adjust the zero knob of light transmittance, and make the number display as. (Adjust 100% t-spin.)

UV752 waits.

3. UV752 752N ultraviolet-visible spectrophotometer use process 1Turn on the instrument switch, and the instrument should be warmed up for 30 minutes before use. 2.

Turn the wavelength knob to observe the wavelength display window and adjust it to the desired measurement wavelength. 3.According to the measured wavelength, the light source switch lever is toggled to manually switch the light source.

200-339nm uses a deuterium lamp, and the switching rod is dialed to the ultraviolet region; 340nm-1000nm use tungsten halogen lamp, and the switching lever is dialed to the visible area. 4.Turn T to zero in perspective ratio (T) mode, put the light shield into the sample holder, close the sample chamber cover, and pull the sample holder lever to enter the optical path.

Press the "Adjust 0%" button, and when "Or" is displayed on the screen, the T zero adjustment is completed. 5.Adjust the cuvette 2-3 times with the reference (blank) dissolving pure sodium solution, pour the reference (blank) solution into the cuvette, the solution amount is about 3 4 of the height of the cuvette, wipe the translucent surface with mirror paper, and put the cuvette into the sample holder in a certain direction.

Close the sample chamber lid and pull the sample holder lever to bring the pants into the optical path. Press the "Tune Up" button, and the screen will display "BL" for a few seconds and the "Mode" or " will appear

1) Preheat the instrument Put the selector switch to "T", turn on the power switch, and let the instrument warm up for 20 minutes. In order to prevent the fatigue of the photocell, do not shine continuously with light, and open the sample chamber cover when preheating the instrument and when not measuring, so that the optical path is cut off.

2) Select the wavelength According to the experimental requirements, turn the wavelength handwheel and adjust to the required monochromatic wavelength.

3) Fixed sensitivity level In the case that the blank solution can be well adjusted to "100%", use the lower sensitivity gear as much as possible, when using, first adjust to the "1" gear, and then gradually increase when the sensitivity is not enough. However, after changing the gear, the sensitivity must be re-corrected to "0%" and "100%". The selected sensitivity should not be changed during the experiment.

4) Adjust t=0% Gently turn the "0%" knob so that the number is displayed as "The specimen chamber is open at this time").

5) Adjust t=100% Put the cuvette containing distilled water (or blank solution, or pure solvent) into the first compartment in the cuvette holder, align the optical path, gently close the lid of the sample chamber, and adjust the transmittance "100%" knob so that the digital display is exactly ".

6) Determination of absorbance Put the selector switch on "a", close the lid of the sample chamber, place the blank solution in the optical path, adjust the absorbance adjustment knob, and make the number display as "000”。Put the cuvette containing the solution to be measured into the other compartment in the cuvette holder, cover the sample chamber cover, and gently pull the handle of the sample holder to make the solution to be measured enter the optical path, and the digital display value is the absorbance value of the solution to be measured.

After the reading, open the specimen chamber lid and cut off the optical path. Repeat the above measurement operation 1 2 times, read the corresponding absorbance value, and take the average value.

7) Determination of concentration The selection switch is rotated by "A" to "C", the sample of the calibrated concentration is put into the optical path, and the concentration knob is adjusted so that the digital display is the calibration value, and the measured sample is put into the optical path, and the digital display value is the concentration value of the solution to be measured.

8) Turn off the power After the experiment, cut off the power supply, take out the cuvette and wash it, and wipe the cuvette seat with soft paper.