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Practical experience in laboratory operations

Dec 19, 2018

Every aspect of the experiment is very important. Ignoring any one of them may lead to the failure of the experiment. Everyone has some good habits in the experiment. They often work together to make experiments and help everyone to learn from each other and collect. Some labs have good habits and discuss with everyone.


Experimental safety:


1. To get into the lab, you need to wear a work clothes. Don't be lucky. If you accidentally touch the acid, it is a small matter to burn a hole in your beloved clothes. Burning the skin is troublesome. Don't be bothered, you must wear gloves to do experiments that are harmful to your body and be responsible for your own body.

2. Wash hands before and after the experiment. If you go to rest and drink in the middle of the experiment, wash your hands. Don't think that the experimental drugs are not toxic. Life is very important. Be careful. Also, if the hands are dirty, you may contaminate the experiment. Instruments and reagents, samples, cause experimental errors. When you are working, don't rub your hands on the white coat.

3. Always operate in a fume hood when it comes to volatile or toxic materials.

4. Be sure to dispose of the waste liquid, sort it, and clean it in time. The toxic and harmful waste liquid should be marked with conspicuous signs. The discarded reagent bottles are discarded without washing. In case the used acid bottles are used, some people will pick them up. It is also dangerous.

Case:

1 A unit of personnel used a waste liquid containing a large amount of toluene as a chromic acid washing liquid (the two colors were close to each other), and they were mixed together, and immediately exploded, and then his eyes left scars.

2 In the process of treating waste liquid once, a bottle of unlabeled liquid was taken into the large waste liquid tank and exploded. Later, I learned that he poured phosphorus oxychloride, which will decompose when exposed to water, and the amount of heat will be amplified.

5. After closing the window to lock the door after work, the weather has changed in the summer, and the laboratory has a lot of chemicals, some are still strong acid, alkali, drugs. Pay attention to water before leaving the laboratory or before entering the laboratory. Is electricity safe?

6. I can't pick up the pipette and pour out the water inside. I don't think the habit is good. If the pipette is not water but other acids or alkalis, how good it is to get to other people's bodies.

7. When placing the rubber plug on the glass tube and the condensing tube, be careful not to use the force. Do not use this to cause long-flowing blood flow.

8. The experimental clothes must be fit, and the cuffs are tightened! It is easy to get into trouble with two large sleeves.

Experimental details:


1. Preparation before the experiment is very important. Prepare adequately before the test. Simple tasks should be taken when the task is obtained. The various reagents, test solutions, instruments, and test procedures, precautions, and previous tests encountered in the test will be encountered. If you want to be clear about the problem, be prepared to avoid getting less and less. If you want to experiment with a new experiment, please ask someone who has done similar experiments. For a test that is not often done, do a detailed test flow chart and paste it in front of the test bench. Special attention should be given to the place where special attention is required. .

2. Keep the lab tidy. After the experiment is done, the medicines are returned to the original position, the used instruments, etc., can be restored to the original state. You can't do where to spread it. Always keep your test bench clean, not only for your good results, but also for yourself. The mood to do the experiment can not be done neat. In the experiment, I developed the habit of cleaning hands. Where and where things come from, it is convenient for yourself and for your colleagues.

3. Do not rush to pour off the stock solution after cooking. Wait for the data to be calculated and then dumped. In case of abnormal data or excessive data, you can recheck without repeated cooking.

4. Regardless of the solution you are loading or what container you are loading, write a label or mark it with a marker to avoid taking it wrong. However, it should be noted that it is marked with a marker. If the quality is not enough, if you accidentally encounter organic reagents or water, you will suddenly disappear. Then, think about N bottles. . . Write a few numbers or labels on the bottle.

5. Sometimes, the configured solution has passed the service life, but it will not be too lazy to be lazy. This is not a good habit. Sometimes it is easy to find a piece of paper to record the weight, and then can't find it. This piece of paper.

6. After the microbiological test, the medium cannot be discarded with household garbage and must be sterilized.

7. The data should be processed immediately after the test is completed and compared with the previous test results. If there is any difference, the cause should be immediately identified and recorded for later inquiry and comparison. Regularly summarize the test data and results, find out the rules, and make a summary.

8. After using the balance, do not clean it immediately, especially some corrosive things, do not clean it immediately, seriously damage the balance balance room, open the door when weighing, do not lightly open the door.

9. Now a lot of experimental data is in the computer, well, backup it every once in a while, so that in case the computer fails before the data is lost, the loss is heavy.

10. Don't chat with colleagues while doing the experiment. Especially in the case of constant volume or titration, attention must be concentrated, and accidentally passed.

11. Can't find shortcuts: For example, measuring or fixing the volume is probably or sloppy.

12. Special emphasis on the analysis, if there is an abnormal phenomenon or data, the contents of the prompt dialog box when the instrument fails, must be recorded, which is very useful for analyzing the problem.

13. It is necessary to know the consumables related to the instruments used. The required preparations should be prepared in advance, and should not be discovered after the consumables are used up.

14. Before adding the reagent, mix it to avoid the uneven concentration and complete the experiment.

15. Immediately after the pipette tip is sucked, remove it from the pipette to avoid taking another reagent with the same pipette when it is in a mess. After the pipette is used up, it should be returned to the large gauge position to prevent the spring from being overdue. Lose the elasticity, be careful to gently absorb the liquid when using the gun, so as not to suck into the gun, it will easily corrode the gun, and it will easily contaminate the subsequent experiments. Don't keep it in your hands when you're not using it, don't turn it upside down (especially when there's liquid inside). To make a standard curve or to continuously and accurately add liquid, use a pipette to add, because the pipette continuously adds liquid, and the spring becomes hot, which will cause deviation of the pipetting.

16. Repeated freezing and thawing in the refrigerator will blur the writing, and can be affixed to the outside of the word with scotch tape.

17. Once you only change one experimental condition, otherwise you will not know which conditional change affects the experimental results. I think it is patience and meticulous to do the experiment. Another point is to be ashamed to ask.

18. The liquid sample stored in the round bottom flask should ensure that the sample has a safe and stable placement. Sometimes, if you are not careful, you may lose all your energy and cry.

19. The bottle in the refrigerator must be placed in a standard and labeled (it can't be used with a marker, even if it is a few days, it may fade), otherwise, no one can remember it for a long time, it is necessary to clean up, if, mistakenly The important product is very troublesome. The glass instrument has fallen off, no matter how important it is, don't pick it up by hand.

20. Each time the drug or reagent is weighed, open the vial and the lid should be turned over on the table instead of being directly attached to the table.

Experimental efficiency:


Plan scientifically, allocate time reasonably, and be busy without chaos. Designing the experimental schedule can do more in a limited amount of time. The laboratory preparation work can be done while the balance is warming up, and the next step of the experiment, such as filtration or preparation of the container, is prepared during the cooking. Use the idle time of centrifugation and electrophoresis to make up the record and make some sorting work.


glassware:


1. Wash out the glassware in time, so that it can be easily washed even after the experiment.

2. Do not put medicines, solvents, solutions or glassware on the edge of the table to avoid breaking.

3. The glassware should be washed and harvested in an oven. The weighing bottle should be dried at 105 degrees and placed in a desiccator. The fixed glassware can only be dried in a 40 degree oven.

4. Standard grinding equipment, after use, must be disassembled in time, otherwise, the time may be long, the grinding may stick very tight.

Reagent

The reagents must be written in a timely and detailed manner. Just make a simple mark on the bottle. After a long time, I have forgotten what the reagents are. Therefore, the reagents are scrapped.

instrument

1. When the instrument is finished, especially before leaving work, do some instrument maintenance work (for example, flushing the column/pipe, etc.), and shut down according to the shutdown procedure to ensure that the instrument has a good state at the next startup. .

2. It is also a bad habit to leave the atom when it is ignited. It is also dangerous to check the atomic absorption of the waste pipe.

3. When doing atomic absorption analysis:

1 The waste liquid pipe must be tied into a waste liquid tank to prevent the waste liquid from flowing back.

2 When doing the analysis of the extract, remember to use the acetone-ethanol mixture (1+1) to burn the flushing line and then rinse it with pure water.

4. When using valuable equipment, you should never go to other experiments when the equipment has not finished entering normal operation. This is to be remembered. For example, some people are making Beckman J25 high-speed refrigerated centrifuge. When the machine is not waiting for the centrifuge to rise to the set speed, it will go away. Well, when the sound rises to the set speed, the sound is not normal. No one knows until the centrifuge is finished, the equipment is finished, and the shaft is slightly off. The reason is The centrifuge tube was cracked, and the outer sleeve was not screwed up. As a result, some of the liquid turned out. When the balance was lost, the sound of the centrifuge was very different. It was repaired tens of thousands, and it was even more difficult to hurt the person. . All equipment must be used with care, whether expensive or cheap.

classification

Drugs and articles should be classified and returned to their homes. In particular, they must be returned to their original position after they have been taken from a laboratory or used in a test. If required, registration is required. For example: the pollution-free test was busy some time ago, and there were a lot of samples, but they were all unordered. I spent a morning in the refrigerator looking for water samples. This is also the case for other people looking for soil samples. Ordered, then you don't waste the experimenter too much time.

saving

I don't cherish laboratory equipment and equipment, don't save medicines and reagents, think that it is very cheap, I don't know about saving lab costs.

recording

1. Carry the experimental notebook at any time during the experiment so that it can be recorded at any time. Recording, not only the recording of experimental data, instrument usage records, environmental conditions or other normal abnormal conditions, phenomena should be recorded in time. Use instrument records for each instrument.

2. Note the gap between the experiments and write down the description of the experimental phenomenon (helpful for the future), carefully record each data, good memory is not as bad as the pen, this is a colloquial language, but don't give up the importance of the pen, the data is good or bad. To recognize the chronological record, you must not randomly write or even tamper with the data, it will bring trouble to yourself, pay attention to the compilation and analysis of experimental data after the experiment.

3. Some people do not have the habit of recording the experimental process in time, and it is easy to repeat the work of the same type of error. In the record, it is especially mentioned that some people only record the right ones, and the wrong ones are afraid of being discovered by the leaders. I think Doing the "records of these failures" is ten times more valuable than doing the right records. These records not only make you and your colleagues less mistakes, improve work efficiency, and even recover losses, such as instrument damage, cause, error in analysis results. The lawsuit and so on. . .

4. As a laboratory assistant, there should be a habit of cherishing data and various records. Do not throw all kinds of data or records, and analyze records or data regularly, especially when abnormalities occur, so as to be as complete as possible. Azimuth to understand the performance of the instrument.

5. Carry a marker with you. Use a number one for the flask, beaker, etc. Don't be bothered, at a glance, it's better than scrambling. If possible, use a dedicated set of utensils for an experiment and mark it with a marker.