I Have a Research Support System

Mo Wenlin had two exams this week, and she was busy with schoolwork, so she suspended her experimental work.

Xu Qiu was also busy writing "Science" articles and had no time to do experiments.

Therefore, the glove box in the laboratory is rarely empty.

Seeing this, Sun Wo saw the needles, decisively occupied the glove box, and began to prepare devices.

During the group meeting in the morning, although Wei Xingsi had no specific statement about the failure of their perovskite team's experiment, it also made Sun Wo feel a little pressure.

So, he decided to rush to make a batch of devices today to prove himself!

It went smoothly at the beginning. The tin-based two-dimensional perovskite film coated this time looks very uniform to the naked eye.

Sun Wo was very satisfied: "This wave is stable."

However, the good times didn't last long, and a tragedy happened during electrode evaporation...

Sun Wo found that no matter how much he turned the potentiometer that controlled the current, the ammeter showed 0.

When evaporating electrodes before, occasionally the fuse would blow due to excessive current.

In that case, the ammeter will simply lose the display because the circuit is broken.

This is the first time that Sun Wo has encountered a situation where the number of current representations is constant at 0.

Sun Wo had nothing to do, so he called Wu Feifei.

Wu Feifei walked to the main console of the evaporation equipment and checked it for a while, but she couldn't figure out the reason.

So, she called everyone in the office over, including Xu Qiu and Duan Yun, to discuss countermeasures together.

After all, the evaporation equipment is used by everyone. If it cannot be repaired quickly, everyone's experiment progress will be affected.

Therefore, we must work together to solve it as soon as possible.

Laboratory instruments are indeed prone to various problems after being used for a period of time.

Some cases are caused by improper maintenance. For example, the circulating water system that broke down earlier is because the deionized water has not been replaced for a long time, and the water in the water tank evaporates naturally, making the circulating water insufficient and unable to operate normally.

Some are damaged due to long-term non-use. For example, a water pump in Zhangjiang’s laboratory was bought by Duan Yun and the others at the time. It was left useless in the fume hood for more than half a year. It was found that the motor of the water pump was rusted.

This is similar to electronic products such as mobile phones and computers. If they are turned on all the time, they will be fine for one or two years of continuous use, but if they are not turned on for a year in a row, they may not be able to be turned on again...

The main reason is that these electronic devices are usually exposed to the air. Once they get wet, the electronic components may be damaged, and the electronic products in continuous use are not easy to get wet.

The energy loss of electronic components due to their own resistance becomes an effective barrier to protect them.

Of course, the working environment in the laboratory is usually harsh, full of organic solvent vapor, coupled with the frequent use of circulating water, the air humidity in the fume hood is also higher than the outside world.

If the instrument is used too many times in the fume hood, it is also prone to problems.

For example, the most vulnerable thing in the organic laboratory is the heating stirrer. After a period of use, there are often problems such as insufficient heating power, slow temperature rise, inaccurate temperature sensor readings, and failure of the stirring function.

Xu Qiu has been in the research group for more than a year, and almost three or four of the heating stirrers have broken down.

It wasn't that he broke it manually, but when he wanted to use it one day, he suddenly found that a certain function failed.

The key is that if this kind of thing needs to be repaired, there are not many places to repair it, and it can only be repaired by the original factory.

And after the warranty period of the original factory, if you change a few accessories, the maintenance price will be about half of the price of the instrument.

Moreover, it takes half a month or a month to go back and forth by express delivery, and then return by express delivery, which is very troublesome.

Therefore, the general solution is to buy a new one directly.

The main reason, of course, is that heating mixers are usually less expensive.

It costs a few hundred yuan each, and it is acceptable to change it once a year.

However, for more expensive equipment such as evaporation equipment, when encountering equipment failure, you can only find a way to see if you can solve it yourself.

If the manufacturer's maintenance workers are called over, it is basically impossible to do it without thousands of dollars.

The maintenance cost of the instrument is based on the price of the instrument. For a six-figure instrument such as an evaporation instrument, the maintenance price will naturally rise.

Duan Yun walked over to take a look, and said in a more certain tone: "The high probability is that the potentiometer is faulty. It may be that there is a problem with the solder, or the inside of the potentiometer is damaged. In short, it should be fine to remove it and replace it with a new one." .”

He is very strong in execution. After speaking, he started to look for tools and prepare to work. At the same time, he suggested: "Sun Wo, I will transfer the soldering work to you. If there is a problem in the laboratory, you can also maintain it. How about it?"

Sun Wo nodded: "Okay."

Seeing someone take over the work, Tian Qing, Mo Wenlin, Han Jiaying and the others returned to their desks one after another.

Xu Qiu stayed, and he recognized Duan Yun's judgment, so he didn't rush to leave, and planned to learn soldering skills together.

He also copied Duan Yun's soldering skills casually, and found that it was 10% of the fifth level.

Seeing the proficiency of this skill, Xu Qiu couldn't help feeling in his heart: "Duan Yun is really good at manipulative ability. Before that, he built a whole set of thermoelectric equipment from scratch. It's a pity that no one can inherit this equipment now. Probably because the thermoelectric field in the group has not achieved any major results, and Wei Xingsi is not willing to go further."

Duan Yun took a new potentiometer from the work box, a screwdriver, a stick-shaped electric iron with a tip that resembles a screwdriver, and a box of rolled-up solder wire.

Xu Qiu still has some general knowledge about soldering, and occasionally saw Duan Yun operating it before, but he has never actually touched it.

The principle of the electric soldering iron is that after electrification, the resistance is heated, and the high temperature at the tip can reach hundreds of degrees Celsius. When the melting point of the solder wire is 50-100 degrees Celsius, the solder wire can be melted and processed.

The solder wire is generally divided into two categories, with lead and without lead.

The one with lead is an alloy composed of tin with a melting point of 232 degrees Celsius and lead with a melting point of 327 degrees Celsius.

Among them, the solder composed of 63% tin and 37% lead is called eutectic solder, and the melting point of this solder is 183 degrees Celsius.

This solder wire has many advantages, including:

Relatively low melting point, easy to process;

The melting point is consistent with the freezing point, which can make the solder joint solidify quickly and reduce the phenomenon of virtual soldering caused by loose components during the cooling process of the solder joint;

Good fluidity, low surface tension, which is conducive to improving the quality of solder joints;

High strength and good conductivity.

But the disadvantages are also obvious, because lead is toxic, so now this kind of solder wire is relatively rare in the laboratory.

Lead-free solder wire is usually used in the laboratory, for example, the solder wire made of tin-copper alloy is used in the group.

After all, the group is all doing chemistry, and they are sensitive to toxicity. Before buying various materials, they usually check whether they are toxic, and then selectively buy materials with less toxicity.

Unless, highly toxic materials have irreplaceable advantages and must be used.

For example, malononitrile used to introduce cyano groups, potassium fluoride used to introduce fluorine atoms, and organotin reagents used to introduce trimethyltin have to be used in order to complete the reaction.

While preheating the soldering iron, Duan Yun took a disposable activated carbon mask and put it on, then turned off the control power of the evaporation instrument, and then used a screwdriver to remove the current heating module on the console of the evaporation instrument.

Xu Qiu found that this electric current heating module looks very large in appearance, with a length, width and height of about 50*20*50 cm, but in fact, less than 10% of the space is filled inside, with only a small potentiometer and a A digital ammeter, and a few wires.

Duan Yun took off the potentiometer with its wires and showed it to Xu Qiu and Duan Yun: "Look, there is a scorched black mark on the back of the potentiometer. It should be that the function of controlling the resistance value has failed. The resistance in the circuit is the highest value, so the current value will always display as 0."

Xu Qiu and Duan Yun thought the same, if it is completely damaged, resulting in an open circuit, the ammeter will not show any readings, and the apparent phenomenon will be similar to a blown fuse.

Duan Yun continued: "Sun Wo, take a picture of the connection wire of the potentiometer with your mobile phone, in case you can't connect it back after it is removed."

Just when Sun Wo was about to do as he said, Xu Qiu noticed that there were 1, 2, and 3 markings next to the three "pins" of the potentiometer, so he interjected: "Let's mark the wires and paste 1, 2, 3 There are three labels, you can directly connect them later, and it will be convenient to change them later.”

Duan Yun nodded: "Alright."

Sun Wo filled out the label, and after a while, the electric soldering iron was preheated.

Duan Yun took a pair of heat-resistant gloves and began to operate.

He first used an electric soldering iron to melt the solder between the original potentiometer and the wires of the current heating module, and removed the broken potentiometer.

Then put the new potentiometer "three-legged" on the ground, hold the solder wire in one hand, and hold the electric soldering iron in the other, and drop the tin liquid after the solder wire melts on the three legs.

Then start wiring, trying to get the wires on the current heating module to solidify on the solder on the potentiometer.

This process is quite cumbersome, and it also requires some patience, because it is necessary to repeatedly melt and solidify the solder, check whether the wire is soldered firmly, and sometimes need to fill up the tin.

However, Duan Yun looked like a veteran at first glance. It only took him more than a minute to fix all three solder joints.

Just as Duan Yun patted his butt and was about to put the current heating module back on, Wei Xingsi suddenly walked into the laboratory with a document in his hand.

He saw Duan Yun squatting on the ground and asked, "What's wrong?"

Xu Qiudai explained: "The potentiometer of the evaporation equipment is broken, and Duan Yun is repairing it."

Wei Xingsi said "Oh", then handed the document in his hand to Xu Qiu, and continued: "They published an article in "Nature Optics", about organic photovoltaic stacked devices, you can read it."

‘The big sub-journal of Nature, laminated? ’ Hearing these two key words, Xu Qiu frowned, took the article, and began to browse.

The highest efficiency, 14.0%.

The device structure, the bottom cell is DTDCPB:C-70, an all-small molecule system;

The top cell is PCE10:BT-CIC, and the non-fullerene acceptor BT-CIC used is a near-infrared acceptor.

BT-CIC, like COi8DFIC, entered Xu Qiu's pre-selected receptor library before, but its performance in the simulation laboratory was not as good as COi8DFIC.

Xu Qiu looked at the other pictures, they were all routine tests, including light absorption spectrum, EQE, J-V characteristic curve and so on.

"How?" Wei Xingsi asked, "It's not a threat to us, right?"

"Hmm..." Xu Qiu responded, "Threats are out of the question, but...if we want to send CNS now, 15% efficiency may not be enough, and it's safer to reach 16% or more."

"That's right, but there's nothing you can do about it. You can't stop other research groups from doing research. Anyway, we've reached 15.5% now. Keep working hard and hope we can do better." Wei Xingsi paused, and added: "Also, it's best to submit this job before our winter vacation, otherwise it may take an extra month."

"I understand." Xu Qiu was not in the mood to continue watching Duan Yun and the others repair the evaporation equipment. He returned to the desk with the documents and planned to study them carefully.

In fact, Xu Qiu has been paying attention to the related trends of organic photovoltaic laminated devices.

But I have never seen anyone do a non-fullerene system before, and this work should be the first article on a non-fullerene stack device.

Judging from this result, there is a high probability that they are also holding back their big moves, and if they don’t make a move, it’s 14%, setting a new world record for organic photovoltaics at this stage. 13.5% of the IDIC-4F system was killed.

However, the other party has done a good job of keeping secrets. There has been no rumors before, maybe it is not a domestic research group?

Thinking of this, Xu Qiu glanced at the author of the article, and found that it was not a domestic research group, but Stephen R. Forrest's research group from the beautiful country University of Michigan, Ann Arbor.

This person Xu Qiu still knows, he is a giant in the field of organic photovoltaics, a beautiful academician of the National Academy of Sciences, has more than 800 papers, the number of citations of the articles is close to 150,000, the H index is 170, and more than 300 patents...

It is interesting to say that the four authors of this "Natural Optics" article, except Forrest, who is the four authors plus the corresponding author, the other three are domestic scholars.

For researchers in mainland China, the names of their papers are very easy to recognize, which is a simple Chinese pinyin, with the first name generally followed by the surname.

For example, although there are many scholars with Chinese names in Bay Area and Kimchi Country, when they write English names, if it is a three-character name, there will be an extra separator "-" compared with mainland scholars, which is easier to compare with mainland scholars. Scholars distinguish.

Some people say: "China's top universities such as Qingbei University are the backyards that provide talents for the beautiful country."

It mainly expounds the phenomenon of "many graduates from domestic top universities have flowed into other countries".

For example, in this article by Forrest, the three authors are all domestic researchers.

To some extent, this statement is indeed not wrong.

For example, undergraduate graduates from the Department of Materials Science and Technology of Shanghai Comprehensive University account for about 30% of each year to go abroad, maintain research, and obtain employment.

Among them, the vast majority of students who go abroad for further study choose the beautiful country, because the top ten universities in the world are basically gathered in the beautiful country.

And the few who can't apply to top international universities may choose to go to Great Britain to study for a master's degree or something like gold plating.

Xu Qiu is not very familiar with the specific situation of Qingbei University, but most of it is similar to Shanghai Comprehensive University.

However, there are indeed more people who go out, but the proportion of returning is not low, because their parents, relatives and friends are all in China.

Maybe only people who immigrate with their families will choose to stay abroad for a long time, but such cases are rare after all.

On the other hand, the increase in the number of people going abroad is also related to the rigid requirements of the scientific research circle for overseas exchange experience.

If you want to engage in scientific research, it is the most cost-effective to go abroad after graduation.

Because some top international universities do not recognize domestic graduate degrees.

A master's degree from Qingbei University may still be useful. If you go abroad with an ordinary master's degree, you may need to study for a master's degree again, which will waste a lot of time.

And if you graduate with a Ph.D. and choose to go abroad to find a postdoctoral fellow, you usually need a large number of high-quality articles at this time.

This is quite difficult for students studying for a doctorate in China.

Xu Qiu's casual AM post is a special case.

The vast majority, 90%, even more than 95% of doctoral students, not to mention AM, it is very difficult to publish an AM sub-journal AEM, AFM.

However, after graduating from a bachelor's degree and going abroad, it takes five years to find a big team, and the difficulty of writing a few AMs is not high.

Although the florists have developed very fast in recent years, one fact that has to be admitted is that the beautiful country is still the world's leader in scientific research.

After all, the other party has hundreds of years of accumulation. Although we have been running for decades, the other party is only walking a little slower, not completely stagnant.

This is a follow-up issue, which is somewhat similar to the "efforts of three generations" and "ten years of cold windows" between countries.

Here is an extreme example.

There are some "notorious" big cow research groups in the scientific research circle of the beautiful country. They only need to accept five or six years of "prison-like life" in them, and they can get a stable CNS.

It is equivalent to exchanging five or six years of life for a CNS, but even so, many people are rushing to it, and not everyone can get in if they want to, and they have to be good enough to be eligible for "going to jail" .

Because once you get a CNS article, you can get a "young thousand" when you return to China, and then do it later, using the experience gained while "going to jail" to "squeeze" domestic graduate students, produce more results, and get a "Jieqing" "Identification is not difficult.

By this time, the path of scientific research has basically been completed. For most scientific researchers, "Jieqing" is the end, and it is relatively difficult for academicians, because there may be hundreds of people queuing in front of them.

Next, you can choose to paddle for the elderly, or you can choose not to forget your original intention and continue to devote yourself to scientific research without thinking too much about utilitarian matters.

In other words, I have basically made it through, got a nearly full-level account in scientific research, and can relatively freely control the rest of my life.

In addition to the scientific research circle, the education system in the beautiful country is also very interesting, which is very different from that in China.

Their strategy seems to be to add all the "points" to college and ignore secondary school.

We often hear how powerful the universities in the beautiful country are, but we seldom hear how powerful their middle schools are.

On the contrary, there are many powerful high schools in China, such as Maotanchang, Hengshui, the High School Affiliated to the National People's Congress, etc. They can steadily output a lot of "test masters" every year.

In Xu Qiu's view, from the perspective of the people at the bottom, domestic practices are generally considered for the people.

And this practice of the beautiful country is actually a means for the capitalists to solidify the class.

Although the beautiful country can harvest the whole world, the total amount of resources is still limited, and it is impossible for everyone to become an elite.

Their structure is also a small group of elites and the vast majority of ordinary people. The existing elites will try their best to organize other ordinary people to transform into elites to snatch their positions.

We seldom hear about involution in the beautiful country, because involution is essentially a process in which ordinary people compete with each other to become elites.

It is almost impossible for ordinary people in the beautiful country to transform into elites, so there is no such thing as involution.

The children of the poor at the bottom, they will go to cheap public middle schools with poor teachers, and then implement "happy education".

This has led to the fact that although this group of people has experienced education, their actual education level is not high. For example, some people still do not think that the earth is an ellipsoid, and still insist on the "local theory".

The children of the rich at the top, they will go to private middle schools with expensive tuition fees and very good teachers. Most of them work as hard as domestic children, and they can usually inherit the "elite" status of their parents in the end.

If you think about it, you can know that if the beautiful country is really all "idiots" cultivated by "happy education", how can it still maintain its position as the world's number one, and it has long been overtaken by flower growers.

They also have a large number of elites supporting the entire country, but in this model, the advantages of all citizens cannot be brought into play, and the hematopoietic ability is insufficient, which may be an inducement for their decline.

In the end, the middle class is the worst everywhere.

Middle-class middle-class children, if they choose public middle schools with poor teachers and implement "happy education", they will most likely fall to the bottom. However, because of better social welfare, there is a high probability that they can spend their lives happily.

There are also a few who are trying to hit the top. Their first threshold is the private tuition fees. Because of the trend of consumption in advance and not saving money, basically don’t expect the family to pay for it, and they can only rely on themselves. Then it is student loans plus work to earn a living.

After studying in a private middle school, the next hurdle is the tuition fee of the university, which is also an astronomical figure. I continued to get student loans, and finally graduated successfully, and found a job that was twice as high as the subsistence allowance.

Then you will find that you need to sell your ten, twenty, or even thirty years of life to repay the cost of your education.

If you take a closer look, isn't this the same as the middle class of your parents?

After working hard for a long time, I finally came out and found that I was still standing still.

Therefore, many people choose to lie flat.

Anyway, the social welfare is good, even if you wait to die, if there is an emergency, the Federal Reserve will release the water, and the government will send money for relief, so just lie down.

Looking at the country, the high-priced school district housing, in fact, already has a taste of a beautiful country.

Therefore, now the country has begun to implement some policies in an attempt to curb the further expansion of this momentum.

Because education is the most universal of several means to break through class barriers, once this road is blocked, the consequences can actually be seen.

This is also an advantage of being a latecomer country, and it can avoid repeating the old wrong path of the predecessors.

If one day in the future, there is no more "involvement" in China, it may be a sad thing, because the high probability is not that "involvement" will be eliminated, but...

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