I Have a Research Support System

When other research groups are doing experiments, it is customary for students from the other research group to conduct experiments, mainly to avoid possible experimental accidents.

Laboratory safety is very important. For experiments like this across schools, it’s okay if there are no accidents. Once an accident occurs, it will be very troublesome to deal with, and it will even affect the departments and schools.

Therefore, even though Xu Qiu had copied Sun Wenyan's skill, TRPL, 10% proficiency level 5, he was still watching with Han Jiaying.

Sun Wenyan explained while performing experimental operations in front of the experimental bench.

Similar to the ordinary fluorescence spectrum PL test, the light absorption UV-vis spectrum should be tested before testing the transient fluorescence spectrum TRPL to determine the wavelength of the excitation light.

The laser used for TRPL is a monochromatic pulse laser. Because the response level of the signal is at the level of a few nanometers or even 100 picoseconds, the laser must be at least at the level of a few nanometers or even 100 picoseconds, so the price is relatively expensive, with an average price of 10,000 yuan. to about 100,000 yuan.

There are three kinds of wavelength lasers in Hou Kaihua's laboratory, namely 425, 565 and 710 nanometers, which can be applied to most experimental situations.

Sun Wenyan first confirmed the use of a 710nm laser for excitation through the UV-vis spectrum results, and then tested the steady-state PL to confirm the approximate intensity of the fluorescence signal of the sample.

After doing the preparatory work, start the TRPL test.

Sun Wenyan put the sample in the card slot in the TRPL test chamber. This card slot is of the upper and lower pressing type and is long strip, which can fix the sample on it.

This is why they asked Xu Qiu to prepare substrates with a size of 1 cm by 4 cm.

Subsequently, Sun Wenyan closed the sample chamber, turned on the laser, turned on the detector, operated the computer software, and started dimming.

The signal detector is very sensitive, and the number of photons passing through it per unit time should not be too many. The indication here is the percentage of the intensity. Generally, it is kept at about 2-4% before the test. The test effect is the best. At the beginning, it is necessary to Use a light reduction filter with a relatively high light reduction ratio, and then slowly reduce the light reduction ratio, so that the intensity value is between 2% and 4%. Sun Wenyan introduced.

Xu Qiu knew that more than 4% should cause damage to the detector, and less than 2%, the signal strength of the sample is too low, the signal-to-noise ratio is low, and the data is not easy to process.

Is the light reduction mirror similar to the ND mirror on the camera? Han Jiaying asked curiously. She was more interested in SLR before and bought a whole set of equipment, but she threw them in the corner after playing with them for a few months. Gray out.

That's right, the same thing is used, and the scientific name should be a neutral density mirror. Sun Wenyan nodded and continued:

The current signal strength is 0.32%, we just need to remove a 10x ND filter, although the ND filter we use has similar functions to the ND filter, but the method of expressing the magnification of light reduction is different.

Among ND mirrors, ND2 means 50% light reduction, ND4 means 75% light reduction, and ND8 is 87.5%. It is more convenient to test.

After speaking, Sun Wenyan pressed a few keys, opened the sample compartment, removed a light reduction filter, closed the sample compartment, and pressed a few more keys. The whole process was very skillful.

Han Jiaying was dazzled and couldn't figure it out. She only noticed that the strength of the sample signal on the screen was between 3.00% and 3.20%, fluctuating constantly.

Xu Qiu understood that Sun Wenyan's operation sequence was to turn off the detector, turn off the laser, open the sample compartment, remove the light reducing mirror, close the sample compartment, turn on the laser, and turn on the detector.

'The detectors were turned off because natural light, lamps, were strong enough to damage the detectors. '

'The laser is turned off because it is afraid that the laser will damage the eyes of the experimenters. Of course, the current power of this laser is not enough to cause such a result, but the rules of optical experiments are like this. '

'This kind of precision optical instrument is troublesome to test, and the degree of automation is not high. When testing PL in the laboratory, put the sample in, set the parameters, click start, and wait for the result to come out. ’ Xu Qiu complained inwardly for a while, and continued to watch the experiment.

There are not many parameters that can be set in the TRPL test software. Most of them can use the default parameters and do not need to be modified. There is only one more important parameter, which is the time scale.

Sun Wenyan didn't know the nature of the sample, so he chose a relatively conservative parameter, 100 nanoseconds, which is suitable for most test situations.

After setting the parameters, start the test.

The instrument began to beep, and the computer screen displayed real-time changing images.

Each data point moves upward from the position on the horizontal axis to the positive direction of the vertical axis.

After more than two minutes, the image stopped changing, and the maximum signal strength at this time was 10,000.

The resulting graph is not a curve, but a scatterplot with a bunch of data points.

Because there are so many and dense data points, the trend can be clearly seen. From the origin, the signal strength increased rapidly to 10,000, and then slowly decreased to about 100.

Seeing the experimental results, Sun Wenyan said with a smile: The measurement went well. The baseline signal is around 100, and the signal-to-noise ratio is not high. The 100-nanometer data can be used directly. It seems that the fluorescence lifetime of your samples is not too short.

Well, this sample is a material with a single component. After that, there are several samples with blended components. The fluorescence lifetime may be shorter. Samples 1 to 12 are similar and should be tested under the same conditions. Samples 13 to 12 are similar. Sample 24 is similar, and samples 25 to 27 are similar. Xu Qiu nodded.

That's great. You don't need to re-test PL and UV-vis for each sample, which can save a lot of experiment time. Sun Wenyan paused and said:

Let's add a WeChat. You don't need to watch this experiment all the time. You can go around and call you after I finish the test. Come and get the data. It is estimated that it will be four or five in the afternoon.

Okay. Xu Qiu took out his phone and added Sun Wenyan's WeChat.

...

After greeting Mr. Hou Kaihua, the two left the laboratory and returned to the campus of Sioux City University.

Speaking of which, Xu Qiu has been in Shanghai for four years, but this is the first time he has come to Suzhou next door, of course, not counting the ones where the train stops.

It feels like we are traveling at public expense. Xu Qiu said with emotion.

Yeah, I thought I'd be busy all day like a light source test. Han Jiaying smiled and said, Brother, what should I do next?

You are a landlord, Xu Qiu glanced at her, Shouldn't I ask you this question?

That's right... Han Jiaying thought for a while, then said, Let's go eat first, and then make plans. I'm treating guests today, so don't compete with me.

Okay, Miss Han will pay for today's expenses. Xu Qiu echoed with a pretense.

Considering that there is still a test here, the two did not choose a place too far away from the school. They chose Yida Plaza near the university town. After all, it is not really a public-funded tour. laboratory.

Yida Plaza has layouts in major cities across the country, and in terms of attracting investment, it still prefers large-scale chain restaurants, clothing, and department stores.

There are not too many people in the shopping mall, which may be because of the working day. After all, except for the students and teachers, most industries have now started to go back to work.

Walking around the mall, Xu Qiu felt that it was not much different from the malls in Shanghai.

Perhaps the prices here will be slightly lower, but it is estimated that the price will not be much lower, at most 10% or 20%.

Han Jiaying stayed at the nameplate of the business on the first floor, staring at the name of the business she settled in, and said to herself: What are you eating...

Xu Qiu pointed to the milky white, hemispherical button under the nameplate and said, Isn't there a button over there? You can randomly choose one of these merchants, which is more suitable for people like you who have difficulty choosing.

Then I'll try it. Han Jiaying pressed the button.

The light flickered after the name of the business, and after a few seconds, it stayed on Chiting Teppanyaki.

But I don't want to eat teppanyaki... Let's do it again!

Kaifeng cuisine... come again! This time you choose what you want, and there are only three things...

Stove fish, this one looks okay, Han Jiaying happily turned her head and asked, Brother, do you eat grilled fish?

Okay. Xu Qiu had no objection, and made a please gesture towards the elevator next to him.

Luyu's store is on the fourth floor, and it's early eleven o'clock. There are not many customers in the store, so there is no need to wait for a table.

The two sat opposite each other, Han Jiaying looked at Xu Qiu, and pointed to the menu, Xu Qiu slightly raised her head in the direction of the menu.

After the silent exchange, the junior girl understood, and she greeted the waiter: One sea bass, sauce and pepper flavor, add potatoes, lotus root slices, thousand-sheet tofu, lettuce four vegetarian dishes, plus one cucumber, one preserved egg tofu , two cans of Coke.

Okay, the clerk explained patiently, Because it needs to be baked fresh, the waiting time may be a little longer, about 20 minutes.

It's okay. Han Jiaying responded, opened Dianping, and looked for nearby places to visit.

Xu Qiu had nothing to do, so he looked up and down the junior girl across from him. He was in a hurry all the way before, so he didn't pay attention to the beautiful woman around him.

Today she seems to have light makeup on, and her upper body is a light blue hooded padded jacket. Because the store is running on the heating and air conditioning, the neckline is slightly torn, vaguely...

Han Jiaying seemed to have noticed his gaze, but she still looked down at the phone, but the frequency of her fingers swiping the screen was obviously faster.

Xu Qiu is a serious person, so he quickly shifted his gaze to observe the decorations in the store.

A few minutes later, the waiter brought two cans of Coke and two straws, and then he came with two small bowls and said, Slap cucumbers, preserved egg tofu.

The side dishes were served quite quickly, but the portion was not much. It is estimated that only half a cucumber and a preserved egg were used, but the price was sold at 8 yuan and 12 yuan.

It has to be said that the gross profit margin of the catering industry is high, Xu Qiu murmured in his heart. He heard from his fourth uncle who was a hotpot chain restaurant before that the gross profit margin of catering is less than 50%, and there is a high probability that it will lose money.

‘It’s true, the rent is more expensive than the next in a shopping mall with such a large traffic volume, especially in the catering industry, basically every year or so, the stores in the shopping mall have to be replaced. '

‘A concrete box made of iron, a business with flowing water. '

After another ten minutes, Han Jiaying said excitedly: I've already made the play plan for the afternoon. After eating, let's go to the video game city first, then go to the secret room, and finally watch a movie. They all happen to be in Yida Inside the square, there is no need to run outside.

Hmm... yes. Xu Qiu nodded and agreed. He was a little worried about the secret room, because he would hand in his mobile phone when playing in the secret room. If something happened to Sun Wenyan and he couldn't contact them, there might be problems.

But after thinking about it, Hou Kaihua's research group had similar working hours to theirs. The experiment started at 1:30 in the afternoon, and the secret room should have been over by then.

However, for projects such as video game city, playing secret rooms, and watching movies, I always feel that adding an express hotel later will not violate it...

Cough, think too much, we are serious people.

Not long after, the waiter brought an iron rectangular grilled fish pot and placed it in the center of the dining table, and introduced: Sea bass, sauce and pepper flavor, the fish can be eaten directly, and the side dishes need to be cooked before eating.

The aroma of grilled fish spreads over the surface, and it is very appetizing just by looking at it.

The fish is divided into two, and the top is covered with a variety of peppers, including pickled peppers, red pepper peppers, green pepper peppers, green peppers, etc. The side dishes are under the fish body, and the soup is bubbling.

Xu Qiu picked up a piece of fish and tasted it.

The bones of the fish body have been removed, and the meat is very delicious and tasty.

However, it is not very spicy. After all, there are different eating habits in different places. Unless it is specially marked as a Sichuan restaurant in Jiangsu, Zhejiang and Shanghai, restaurants generally do not make their dishes particularly spicy.

...

After eating and drinking, the two strolled downstairs to the video game city.

Just happened to meet an event, and you can buy 25 coins for 9 yuan on Dianping. The two combined and bought 50 coins.

Xu Qiu has two mobile phone numbers. He originally wanted to change the number to make more money, but found out that this activity is bound to the mobile phone information, and a mobile phone can only be used once, so he had to give up.

It's okay, just buy it if you don't have enough fun. Han Jiaying patted her chest and said.

Xu Qiu nodded, he almost forgot, this is a little rich woman, not short of money.

But they now have 50 coins, as long as they don't play gambling machines such as coin pushers, under normal circumstances, it is enough to play for a while.

Exchange coins at the front desk, holding a small basket full of game coins, the two punched in together:

Shooting game, two rookies, one round tour, successfully wasting 12 coins;

Racing game, with Xu Qiu's C1 driver's license in his hand, he felt that there was no difficulty at all. He rode the best, but the school girl frequently overturned the car;

In the shooting game, the two played side by side 1V1. Xu Qiu deliberately let the water go, but he still won;

Dancing machine, the school girl danced pleasingly, attracting passers-by to stop and watch;

And when it was Xu Qiu's turn to take the stage, the stiff dancing posture made him feel hot eyes. In the end, he blushed, stopped dancing, and just stepped on the notes with a blank face.

The store is very large, but there are many repetitive items. The two of them walked around, except for claw machines, arcade machines and various gambling machines, they have played almost everything else.

In the end, the two stopped in front of rows of claw machines.

At this time, Xu Qiu still had more than 20 coins in his hand.