I Have a Research Support System

After clamping the blank silica gel column filled with silica gel on the iron stand, Xu Qiu called Chen Wanqing out to deal with the waste liquid and the experimental garbage accumulated these days.

"By the way, have we paid back the liquid nitrogen coupons we owed to the cryogenic physics laboratory?" Xu Qiu asked. He remembered that the place where the waste liquid was disposed of was very close to the cryogenic laboratory.

"I paid it back. Later, I did a low-temperature reaction again, and went to make another pot of liquid nitrogen. I used up three tickets. I put the remaining liquid nitrogen tickets in the drawer of the A501 office," Chen Wanqing regretted. : "It's a pity that the two pots of liquid nitrogen that I pumped last time were not used up at the time, and then they all evaporated and ran away."

"That's right." Han Jiaying interjected, "Why don't we use it, such as liquid nitrogen ice cream, or making frozen pears with liquid nitrogen seems to be good."

"Just know how to eat." Xu Qiu laughed.

There were no twists and turns in the disposal of waste liquid and experimental garbage.

Because the waste liquid in the laboratory is marked with the main components, and there is no special waste liquid such as hydrofluoric acid, so the school of pharmacy has registered and accepted all of them.

Xu Qiu went out to get some air, and returned to the laboratory again. The vacuum-dried product had been completely dried.

The product was redissolved with dichloromethane, the sample was mixed, and rotary steamed.

Put the mixed product in the 10% space reserved above the blank silica gel column, compact it vertically downward with a gasket, install a deflector, and finally screw the top cover of the silica gel column tightly.

Among them, the main function of the gasket and the flow deflector is to make the mobile phase passing into the silica gel column uniform in the horizontal direction.

Compared with disposable silica gel columns, manual column filling is much more troublesome.

The quantity of the two products was not much, and the junior girl could handle it, so Xu Qiu didn't keep more.

After returning to the office and washing his hands, Xu Qiu looked back at the senior sister who was following the show, and couldn't help but think of pyridine.

There is a well-known saying in organic laboratories, "Men don't use pyridine, and women don't use furan."

It means that if these two solvents are used for a long time, exposure to these two types of solvent vapors will affect the reproductive function of men/women.

One for spermicide and one for contraception.

Of course, these two solvents are only caught by people. Most organic solvents have potential carcinogenicity, teratogenicity, organ toxicity, and reproductive toxicity.

In the "Organic Chemistry" course before, Xu Qiu generally understood that there is a set of international classification standards for organic solvents, which can be divided into Class I, Class II, and Class III solvents.

At this time, he just had some free time, so he checked the Internet by the way, and he could also give himself a vaccination. There is never too much knowledge about safety.

"The so-called Class I solvents are solvents known to be carcinogenic and harmful to humans and the environment. Avoid using them as much as possible. If it is unavoidable, the residual amount must be controlled within the specified limit:

Benzene (2ppm), carbon tetrachloride (4ppm), 1,2-dichloroethane (5ppm), 1,1-dichloroethylene (8ppm), 1,1,1-trichloroethane (1500ppm). "

Xu Qiu thought to himself, the brackets should be the requirements for their residues, the first four are all within 10ppm, that is, within one hundred thousandth.

There are only five kinds of solvents in the first category, and it is not easy to stand out from a bunch of organic solvents. Two benzene and carbon tetrachloride are more famous, and he is quite familiar with them.

Benzene is a product of early petrochemical industry. It used to be a popular organic reaction solvent. Later, it was banned by many parties because of its great harm. Now it has basically withdrawn from the stage of history and is replaced by its derivatives, such as toluene and chlorobenzene.

Carbon tetrachloride is a fire extinguishing agent with strong fire resistance. There used to be a fire extinguisher with carbon tetrachloride as the main component, but because it is easy to form highly toxic phosgene, and it is very destructive to the ozone layer, it will The hole that leads to ozone has been banned many years ago and has been gradually replaced by carbon dioxide and dry powder fire extinguishers.

"The second category of solvents refers to solvents that are non-genotoxic but carcinogenic to animals, including 26 types such as..."

'This is used a lot in the laboratory. ’ Xu Qiu secretly counted the solvents he had been in contact with, counting them with his fingers while checking the list.

There are 10 kinds in total, just don't need to borrow toes:

Chloroform, chlorobenzene, dichloromethane, N,N-dimethylformamide, ethylene glycol, n-hexane, methanol, ethylene glycol methyl ether, N-methylpyrrolidone, toluene.

"Ten out of twenty-six..." Xu Qiu did some calculations, "I have been exposed to 38% of the second-class solvents. This ratio is not low. As the experiment progresses in the future, the ratio will definitely increase. taller. '

Chloroform and chlorobenzene are solvents for organic photovoltaic cells;

Dichloromethane, toluene, and N-methylpyrrolidone are solvents for organic synthesis;

N, N-dimethylformamide is one of the commonly used solvents for perovskite, which was used in the perovskite transport layer before;

Ethylene glycol is the cooling liquid of the low-temperature circulation device;

n-Hexane and methanol are solvents used for Soxhlet extraction and purification of polymer donors;

Ethylene glycol methyl ether is a solvent used to prepare zinc oxide precursor solution.

Of course, some solvents have more than one function, such as:

Chloroform was also used as a solvent for synthesis reactions and for Soxhlet extraction of polymers, and methanol was also used as a polymer donor material and an anti-solvent for PDI acceptor materials.

Xu Qiu noticed that pyridine was also included in the second category of solvents, but he hadn't come into contact with it yet.

‘I heard that pyridine has a unique smell. Before leaving at night, do you want to go to the laboratory to smell it? '

‘Emmm... don’t play it safe. '

"The third class of solvents, low toxicity solvents, including ethanol, ethyl acetate, tetrahydrofuran, acetone, isopropanol, etc."

Xu Qiu was slightly surprised. Ethanol and the like are easy to understand, but tetrahydrofuran is actually in the third category.

Furan is as famous as pyridine, and he thought it was also a second-class solvent, but the toxicity of tetrahydrofuran written on the MSDS is indeed very low.

But in any case, it is better not to contact directly or not to contact.

"Other solvents that are not in these three categories do not mean that there is no risk at all. It may be because the niche has not been widely concerned or there is no toxicological data. For example, ether, although it is not in the above three categories, but high concentration of ether will make People go into shock and even die.”

After reading, Xu Qiu deleted the webpage, and the useless knowledge seemed to increase again. He deeply felt that the laboratory was too dangerous, and he should pay more attention to protecting it and posting a few more in the future.

After that, Xu Qiu stayed in the office and concentrated on writing the review, pushing the progress of the third part which he was in charge of to almost 60%.

At around five o'clock, Han Jiaying completed the separation and purification of the two products, and obtained 55.1 mg and 53.6 mg of the product respectively. Then, she dragged Xu Qiu from the office to the laboratory, and shook the samples like a treasure. Two Clear Glass Bottles.

"Not bad." Xu Qiu was full of praise. The 3D-PDI material obtained by the school girl was also a dark red powdery solid, which was similar to the color changes of the several 3D-PDI materials he synthesized, except that the degree of lightness and darkness was different.

He conveniently copied the two materials into the simulation laboratory II and arranged them for the simulation experimenters.

"Brother, I'll be counting on you tomorrow." Han Jiaying chuckled lightly.

"No problem." Xu Qiu directly agreed. According to the previous division of labor, he was responsible for the preparation of the device, and the younger sister and the younger sister were responsible for the synthesis. Then, he pointed to his fume hood and said, "These three reactions need to be handled by me tomorrow. Down."

"Okay, it's the photocyclization reaction catalyzed by iodine. I remember the post-processing step is..." Han Jiaying said slowly while recalling.

"Yes, the three reactions are the synthesis of second-generation 3D-PDI molecules. I have recorded the dot plate results of the 5/6 series, and I can directly compare them at that time. The difference between the 8 series and the 5/6 series will not be very big .” Xu Qiu nodded in satisfaction.

His progress is relatively fast, so he has given the junior a make-up lesson in advance for the operation steps and post-processing of the subsequent experiments, and now it seems that she has mastered it pretty well.

...

After dinner, the laboratory turned into Chen Wanqing's stage.

Xu Qiu and Han Jiaying stood at the door of the laboratory, watching the senior put on the gas mask seriously, with a look of death.

"Come on." "It's okay." The two encouraged the senior sister, and she looked better, and walked into the room.

After walking a few steps, Chen Wanqing heard a "click", obviously the door of the laboratory was closed, she paused, shook her head, and continued walking.

Their approach is correct. If the laboratory must use volatile reagents with an unpleasant smell, the impact must be controlled within the laboratory and cannot spread out.

There are no people in the Zhangjiang Microelectronics Building, so it doesn't matter. If it is the Handan campus, the entire building is the laboratory and the offices of the teachers. If there is a leak, the consequences will be much more serious.

Before, there was a laboratory on the fourth floor in Caiyi. The thiol reagent leaked and spread to the entire building along the corridor. A rotten garlic smell could be faintly smelled at the gate on the first floor. Of course, the fourth floor was the most affected. All the teachers and students on the entire floor went out to evacuate for half a day.

Including the glove box in Mr. Wei's laboratory, the atmosphere in the glove box is periodically regenerated, in essence, the solvent molecules in the glove box are discharged into the atmosphere. Every time the regeneration is performed, the door is closed and the windows are opened wide for ventilation. , otherwise it will leak into the corridor.

Solvents such as chlorobenzene, chloroform, and DMF do not smell so good. They smell astringent, which is hard to describe.

Back in the office, Xu Qiu received the completed cover picture from Tian Qing. The round PC[70]BM molecule in the previous drawing has been changed to an ellipsoid shape.

After the whole picture is colored and post-processed, although it is in a cartoon style, it has an inexplicable sci-fi feel, and the effect is very good.

Xu Qiu immediately said that there was nothing wrong with it, and his main task was just to check. The rest of the liaison with the editor was taken care of by Mr. Wei.

An hour later, Chen Wanqing reappeared at the gate of A501.

"Senior sister is back, why..." Xu Qiu suddenly stopped, and sniffed the surrounding vigorously, there was a smell that seemed to be there, "Pyridine, it really lives up to its reputation."

"Sorry, it should be that pyridine is attached to the clothes." Chen Wanqing smelled it on her body and frowned, "I can't smell it myself."

"I can't smell it either..." Han Jiaying shook her head in confusion.

"I only used one milliliter of pyridine. It shouldn't be such an exaggeration, but there is a smell in the laboratory. When I took off the gas mask, I was disgusted." After washing her hands, Chen Wan opened the window and started to ventilate.

"Maybe different people have different sense of smell." Xu Qiu explained.

Opening the windows is still very effective. With the continuous exchange of air between the room and the outside, the smell of pyridine is basically gone.

...

Before leaving Zhangjiang at night, Xu Qiu brought the three 3D-PDI products synthesized today. These products had been packed in garbage bags and placed in the corridor before Chen Wanqing started the experiment.

Then the three of them summed up the progress of their respective reviews. Chen Wanqing was the fastest, with 90% completed, Xu Qiu and Han Jiaying were evenly divided, with about 80% completed.

By the looks of it, in one more day, the third part of the review will be complete.

On the school bus back, Xu Qiu entered the simulation laboratory II and obtained some experimental results.

The efficiency of the third-generation 5 series reached 5.98%, which is 0.57% higher than the 5.41% of the second-generation 5 series.

In addition, the best fit donor was changed from PCE10 of the second generation to P3TEA, which was consistent with that of the first generation.

"What do you mean by stepping on two boats and jumping sideways repeatedly?"

Xu Qiu made a fuss casually, then thought of the performance of the device, and couldn't help shaking his head.

The PDI series is really exhausting, and the efficiency is improved bit by bit.

However, it is a good thing to be able to improve, at least it shows that the previously designed route is correct.

Moreover, because now he can only get 3000 system points per week, he can’t make ends meet if he uses it casually. Xu Qiu can’t use the simulation lab II as he likes, so what he gets in the simulation lab are preliminary exploration results, the purpose is just to verify the route is it right or not.

After all, no more than six to ten hours of exploration are allocated to the same system, and several donor materials must be tested.

Since the time flow rate is synchronized, this time in reality is just to make one or two batches of devices.

In other words, when Xu Qiu conducts experiments in reality, there should be a lot of room for improvement and improvement in device performance.

As for the current path he designed, the third generation of 3D-PDI molecules is basically the final state.

If you count the side chain modification at the nitrogen atom position, that is, the 5/6/8 series, it can be regarded as the development of four generations.

In terms of molecular structure optimization, it is considered relatively complete.

The main reason is that all the active reaction sites are now occupied. If you want to further optimize, it is not impossible, but you must redesign the molecule and synthesize it from scratch.

Many optimization strategies are mutually exclusive. For example, the introduction of heteroatom selenium cannot be modified with side chains at the bay position, and vice versa.

After analyzing his own system, Xu Qiu looked at the two materials of Xia Xuemei. The current exploration of device performance has not yet been completed.

He was surprised to find that the current highest results of the two systems are 3.92% and 4.77%, respectively.

This result is already very good, comparable to the system he designed himself, and may even surpass his system after getting the final result.

Xu Qiu muttered to himself, could it be that the more complicated the 3D-PDI, the more NB?

After exiting the system space, Xu Qiu looked at Han Jiaying who was curled up in his arms, sleeping soundly, her eyelashes still moving from time to time.

Announce the good news to her after finishing the device tomorrow.