Where can I find the FL2200 2 chromatography time setting?

Haha, where to find the time design from 2200 to 24 spectrum You are mainly looking for him, his setting only sets the switch. Set there to find his of220 chromatography quad just not in time. It should be possible to find it, and he also has an instruction manual, and there are also instructions to follow his steps step by step.

Just walk!

The FL2200-2 chromatography time is set in three small dots, and there is a setting button inside after you click it.

Well, if you set the time, you can usually find it in the control panel.

Of course, the events of the chromatography have to go to the settings to be set, and there is one on the far right of the open settings.

FL200-2 chromatography time setting, you can go to that setting and look for it.

If you want to set the fl 200024 time, you can change it in the settings panel.

Where can I find this bichromatography time setting? You can go to the general supermarket to have this! I'm in a specialty store.

As for the device time, you can go to the settings to find it.

Where to find the 200 bars 25 time setting of the small white building, it should be in the upper left of the city hall.

This style spectrum time design should be available in a case in the lower right corner.

In this case, it is recommended that you also choose to go to our field to find out the more suitable ones, so that you can find out the spectrum well.

If you have time, we recommend that you choose to look for it from our illuminators.

I'm in 200, and his color woman is not also set up, and he is also very happy if he is looking for each other?

The tone here is also set on him there to find some misunderstandings as well as specific methods.

How to set up the non-salt section? How to find a gear button in the top right corner, so you can go there and set it up.

Chromatographic time setting to find? You should look for it in the settings.

FL2000-2 Sheep time setting where to find I don't know.

1.Advantages of chromatography High separation efficiency. Dozens, if not hundreds, of compounds with similar properties can be separated on the same column, solving complex sample analyses that many other analytical methods cannot handle.

Fast analysis. In general, chromatography can analyze a complex sample in a matter of minutes to tens of minutes. High detection sensitivity.

Advances in signal processing and detector fabrication have made it possible to detect trace substances in the 10-9g range without pre-concentration. With pre-concentration, the lower limit of detection can be in the order of 10-12 g. The sample amount is small.

A few nanoliters to a few microliters of solution sample is typically required for a single analysis. Good selectivity. By selecting the appropriate separation mode and detection method, only a fraction of the species of interest can be separated or detected.

Simultaneous analysis of multiple components. In a very short time (about 20 minutes), dozens of components can be separated and quantified at the same time. Easy to automate.

Today's chromatography instruments can be fully automated, from injection to data processing. 2.Disadvantages of chromatography Poor qualitative ability.

To overcome this shortcoming, the use of chromatography in conjunction with a variety of other qualitative analytical techniques has been developed.

(1) Reduce the flow rate of the mobile phase, but make the analysis time longer.

2) The amount of stationary phase is reduced, but the amount of sample loading in the column is also reduced.

3) Reduce the particle size of the stationary phase, but not excessively, and the permeability of the column will also decrease.

4) The low viscosity mobile phase is selected to facilitate rapid mass transfer, but it is not conducive to multi-component analysis.

5) Appropriately increasing the column temperature can reduce the viscosity of the mobile phase, but the column efficiency and resolution will also be reduced.

6) The volume of the stagnant mobile phase is minimized, but the flow rate of the mobile phase is accelerated.

Answer: 5What is the basis for the application of atomic absorption spectroscopy for quantitative analysis? What are the methods for quantitative analysis? Similarities: By gradually changing the analysis conditions, the hard-to-flow substances are accelerated while ensuring the separation of the substances.

Retention time locking is the retention time of a particular compound that remains constant across different instruments and columns (but with the same nominal stationary phase and comparison).

1. Overview. The factors that determine the retention period are as follows:

1. The properties of the compound and the properties of the fixative solution.

2. Operating conditions. i.e., carrier gas velocity, column temperature, capillary column size, detector type, etc.

2. Detailed description.

1. Carrier gas control.

For the same type of carrier gas, pressure and flow rate are parameters that affect the retention time;

The manufacturing accuracy of pressure gauges and flowmeters of different manufacturers is different, so when the pressure and flow rate of different instruments are completely consistent, the flow rate in the column is also different;

Now with EPC, this problem has been largely solved; Although it is not possible for all EPCs manufactured by the same manufacturer to be strictly consistent, the differences are small and can be compensated for by automatic pressure adjustment.

2. Temperature control.

Retention time is extremely temperature sensitive, and reproducibility was clearly problematic when measuring column temperature with a mercury thermometer in the past. Nowadays, thermal elements and electronic circuits are used to control the temperature, and the accuracy is greatly improved. Satisfactory temperature reproducibility between different instruments.

Even if there is a difference in temperature, we can still reproduce the retention time by adjusting the pre-column pressure.

3. Column specifications.

Columns from different manufacturers, although the nominal specifications are the same, are inevitably subject to uneven internal diameters, variations in fixative film thickness, and inaccurate column lengths, which can cause fluctuations in retention times.

The same column can be changed during use, such as after remounting or truncation of 1 2 cm due to column contamination, and the retention time cannot be reproduced if other operating conditions remain unchanged.

At present, the reproducibility of column manufacturing from the same manufacturer is quite high, while the columns from different manufacturers are not fully reproducible, especially for polar columns. But if we use the same manufacturer's column, we can basically solve this problem. As for the change in column length, it can be compensated for by adjusting the pre-column pressure.

4. Detector type.

Conventional detector: works at atmospheric pressure;

MS: working under high vacuum;

AED: Operates above atmospheric pressure (e.g., 10kPa).

Thus, when comparing the results obtained with a conventional detector to MS or AED, the column pressure drop is different and the retention time cannot be reproduced, even if the pre-column pressure is strictly consistent. With EPC, it is easy to adjust the pressure to keep the column pressure drop the same.

Commonly used quantitative methods for chromatographic analysis: normalization method, internal standard method, internal standard method, internal (incremental) internal standard method, external standard method.

1. The advantages of the area normalization method are that it is simple and accurate, and it has little influence on the results when the operating conditions change, and it is suitable for analyzing the content of each component in a multi-component sample. However, all components in the sample must be peaked, so the use of this method is somewhat limited.

2. The external standard method is to prepare a series of standard solutions with different concentrations of pure substances (or directly purchase standard solutions of different concentrations) to take a certain volume and inject them into the chromatograph, and make a standard curve according to the peak area and concentration. The concentrations of the required components can be found from the standard curve under the same operating conditions and methods as the standard curve for the analysis of unknown samples (the concentration can now be found directly on the workstation). This method requires accurate injection, stable operating conditions, and consistent conditions for the analyzed sample and the standard curve.

3. The internal standard method can be used when all components in the sample cannot all be peaked or only one or several components in the sample are required to be determined. The internal standard method is to accurately weigh a certain amount of sample, add a certain reference material (internal standard), and calculate the content of the component to be measured according to the quality of the internal standard and the sample and the corresponding peak area on the chromatogram. The key to the internal standard method is to select the appropriate internal standard, which should be a pure substance that does not exist in the sample, which is similar to the substance to be measured, and can be dissolved in the sample, but cannot react in the sample.

This method is cumbersome and generally not used for quick analysis.

In high-performance liquid chromatography, stationary phases can be divided into forward chromatography and reverse chromatography1 Normal-phase chromatography.

Polar stationary phase (such as polyethylene glycol, amino and nitrile bonded phase) mobile phase is used as a relatively non-polar hydrophobic solvent (alkanes such as n-hexane, cyclohexane), ethanol, isopropanol, tetrahydrofuran, chloroform, etc. are often added to adjust the retention time of components, and it is often used to separate medium-polar and highly polar compounds (such as phenols, amines, carbonyls and amino acids).

2 Reversed-phase chromatography.

Non-polar stationary phases (e.g., C18, C8) are generally used

The mobile phase is either water or buffer.

Methanol, acetonitrile, isopropanol, acetone, tetrahydrofuran and other organic solvents that are miscible with water are often added to adjust the retention time.

It is suitable for separating non-polar and less polar compounds.

RPC is the most widely used in modern liquid chromatography.

According to statistics, it accounts for about 80% of the entire HPLC application.

1. The sample is not entered or the injection amount is too small (the shunt ratio is set too large) 2. The carrier gas is not turned on, or there is no more.

3. The sample response is too low, or there is no response on this detector.

4. The detector is not turned on (or there is no ignition), or the detection selection in the method is wrong.

5. The signal channel is not selected correctly.

Different detectors, different situations.

1.The height is not enough;

2.insufficient gas volume;

3.The peak is too high;

4.phase dislocation;

5.The color lacks vividness.

The basic equipment of a gas chromatograph consists of six parts:

Pneumatic system: The channel through which the gas flows, including the gas source, the gas purification device, the flow control valve, the pressure gauge, the chromatographic column, the detector and the exhaust gas discharge channel, etc.;

Function: The carrier gas output by the air source passes through a purifier equipped with a catalyst or molecular sieve to remove harmful impurities such as water and oxygen, and the purified carrier gas passes through the pressure stabilizer valve or automatic flow control device to make the flow rate output constant according to the set value.

Injection system: A device that enables a small amount of sample to enter the chromatographic column accurately and sufficiently, including an injector (manual or automatic sampler), an injection chamber, and a shunting device;

Function: After the specimen is vaporized in the vaporization chamber instantaneously, it enters the chromatographic column with the carrier gas for separation.

Separation system: is the separation core of the chromatograph and is performed in the column.

Function: Separation of mixtures with different compositional properties.

Detection system, including detector, magnifying glass, monitor power temperature control device.

Purpose: Detection of the substance signal in the sample, performed by the detector.

Temperature control system: A combination of circuits and mechanical components including processors (CPUs), function keys, numeric keys, heating keys (or running keys), etc.

Purpose: Precise control of the temperature of the individual components.

Signal amplification and recording system: The recording device has gone through three generations: a recorder, an integrator and a data processing system (also called a chromatography workstation).

Function: The signal collected by the detector is amplified and output to the recording device, and the amplification of the signal is completed by the transistor circuit.

The basic equipment includes the carrier gas supply system, including the gas supply cylinder (or air source), the pressure reducing regulator, the filter operator, the flow controller, the flow indicator, etc., and the carrier gas flow is generally controlled at 10-200ml min.

Separation column, the column is the heart of the gas chromatograph, the separation of the sample analysis is all carried out in the column, at present, in the gas chromatograph, packed column, capillary column and packed capillary column are used the most.

Injection systemThe injection system is designed to precisely adjust the amount of injection per analysis while ensuring that the liquid sample is converted to the gas phase and then added to the carrier gas stream, so it has a vaporizer that can be adjusted at the temperature. The switching of the rotary valve can be operated by manual or automatic program control systems.

detectors; The detector converts the components of the material outflow into an electrical signal output, and is amplified by the amplifier and recorded by the recording instrument or quadrated, displayed and printed by the data processing device. Detectors include not only thermal conductivity detectors, but also hydrogen flame ionization detectors and various radioactivity detectors.

Power supply and signal amplification recording, processing device, gas chromatograph detector power supply requirements are stable, when using a thermal detector, there should be a DC regulated power supply, on the other hand, the signal output by the detector is often milliampere or microampere order of magnitude or even smaller, so it must be amplified.

Thermostatic process control system, chromatographic column, detector and vaporizer, these components are required to work at a certain temperature, so in the chromatograph, these three components are installed in a thermostatic chamber, and the thermostatic control system controls the stable temperature. The accuracy of constant temperature control is generally in the soil, and the program control system includes automatic feeding, automatic attenuation of peak output, program heating, automatic switching of columns, etc.

Because modern chromatography analysis technology has two functions of separation and analysis, that is, it can eliminate the mutual interference between complex components and qualitatively and quantitatively analyze the components one by one, therefore, modern chromatographic analysis technology is very suitable for the effectiveness evaluation of crude drugs with complex components.