Chapter 288: Do you have a habit of dying if you don’t mess with people?
This year is different from previous years. The Mid-Autumn Festival is held on Saturday and Sunday, and Xu Qingzhou and Song Yao are basically at home.
Monday the 28th.
Song Yao went to Professor Li Daiyue to talk about applying for exemption from classes, while Xu Qingzhou stayed at home to perfect Professor Zhao Shengwen's experimental model.
After so long accumulation, there is already a complete multi-physics coupling model that can effectively describe the interaction between multiple physical fields such as electrochemistry, thermal and mechanics.
Xu Qingzhou opened the folder and discovered that during the month he went to Switzerland, Professor Zhao and the others had made some new attempts.
For example, porous silicon nanomaterials were prepared using coal-based kaolin and magnesiothermal reduction in an Ar atmosphere after chemical etching.
"It works well."
Looking at the data chart, Xu Qingzhou nodded.
This material has a first discharge capacity of 3388.8mAh·g^-1 and a charge capacity of 2710.7mAh·g^-1. Under the condition of 100mA·g^-1, it still provides 546mAh·g^-1 after 100 cycles. reversible specific capacity.
The battery performance is high, but the shortcomings are equally obvious. The preparation process is complicated and it is unlikely to be mass-produced.
In addition to this, the research team also chemically etched commercial Al-Si alloy with alkali to prepare nanoporous silicon materials.
The initial capacity is as high as 3003mAh·g^-1, and the capacity of 1000mAh·g^-1 is maintained after 300 cycles at 0.3C.
In actual applications, silicon materials are basically coated with a layer of carbon to increase their conductivity, while also increasing the spacing between materials to improve their electrochemical performance.
Xu Qingzhou watched with gusto.
I used to often hear people say: "The value of a graduate student does not lie in how much knowledge you learn, but in how much knowledge you create. No matter how much you learn, you are just a library at best, and the outside world's evaluation of you will only be based on your Work.”
Xu Qingzhou agreed.
However, the accumulation of knowledge is equally important.
I don’t have time to do the experiments myself now, so I can only read the information and accumulate some experience. After all, batteries will be a hot research topic for quite some time in the future.
There is also experimental data related to lithium dendrites.
There are various graphic and text data, including the relationship between the net change of Li dendrite length in the crack and the capacity during a fixed charge and discharge cycle, and the relationship between voltage and time.
[Li/Li6PS5Cl/Li at 7MPa stacking pressure, current density 3.0mAcm-2 and capacity 3.0mAhcm-2]
Xu Qingzhou's current job is not particularly difficult, it is to use the latest data to iteratively process the model.
Data is more real than human perception. Through data, we can understand the internal structure of new samples so that we can better adjust parameters and determine a better material ratio.
Xu Qingzhou went through all the data before importing the data into the model.
Song Yao went to Professor Li with the printed application form.
In the office, after getting the application form, Li Daiyue took a look at it and saw that there was nothing wrong with it, and then handed Song Yao a USB flash drive.
"On the 8th of next month, Professor Dong Yixuan from Nanjing University will lead a team to come over for exchanges. Here are the meeting materials. You can familiarize yourself with it."
"Okay."
Song Yao looked at the materials, and Li Daiyue stood up, took the application form and went through the process.
In fact, Song Yao could also send the application form herself, but in the end it was better for her to do it herself, which would save a lot of trouble.
"Director Cao."
"Professor Li."
In the office, only Cao Jingyu, the head of the Department of Economics, was there.
As soon as Cao Jingyu met, he smiled and asked: "I heard that you want to accept Song Yao from our department as a student?"
"Well, this little girl is very talented." Li Daiyue nodded.
Cao Jingyu chuckled and said: "I have seen this child's grades and test papers, and they are indeed very good. Is she dating Xu Qingzhou from the School of Mathematics?"
"You also know?" Li Daiyue was confused.
"Everyone is saying that it is difficult not to know. Moreover, at the last conference, when I met old people from the School of Economics, they were still joking with me, saying that our School of Economics is my mother's family."
Li Daiyue discovered that apart from her, the whole world knew about her prospective apprentice and Xu Qingzhou.
At the beginning, I was still worried that the prospective apprentice would be affected by the object and his studies, but now it seems that the situation has reversed?
No, Xu Qingzhou is very powerful, and her future apprentice will not be weaker than others.
This little girl is amazing.
"Did these two young men start dating in high school?"
"They were in the same class in high school, probably at that time."
Li Daiyue frowned and said, and immediately realized that she seemed to have been taken into the ditch of gossip, "This is Song Yao's application for exemption from classes."
"Application for exemption from class?"
"Well, I have tested it myself. This girl is at least a senior in college."
"This"
Cao Jingyu looked at the application form, thought about it, and said: "It seems that you really value this student, and you have to go through the application form in person. Well, if she can pass your test, she is definitely not weak. Besides, her The results are obvious to all, and this is not a problem.”
September 30th.
The day before the National Day holiday, Xu Qingzhou sent the battery analysis results to Professor Zhao. For example, in group D samples, phenolic resin and graphene oxide were added in sequence to prepare a precursor gel, and then the precursor was obtained through freeze-drying and high-temperature carbonization. .
The silicon-carbon composite material prepared according to this step has the best effect.
According to model speculation, the first discharge capacity can reach 2455mAh·g-1. At the same time, the reversible specific capacities at 0.1, 0.25, and 0.5C are approximately 1679mAh·g-1 and 1285mAh·g-1 respectively
Of course, the model can only be simulated based on data to form a guess. Professor Zhao and Senior Brother Wang Wei need to verify it themselves.
Song Yao's application for exemption from classes was successfully passed. She no longer had to go to class, but she was busier than before.
Li Daiyue gave Song Yao a reading list and asked Song Yao to take the time to read all the books on it.
The holidays for research groups in universities will be reduced, and sometimes they will not even exist at all. Fortunately, Professor Li Daiyue still gave the department a three-day holiday.
During the National Day holiday, the two of them didn't plan to go out to play.
Neither Xu Qingzhou nor Song School Beauty are the kind of people who like to join in the fun, especially during such a big holiday. Every place is overcrowded. Going out is not so much about having fun as it is about counting heads.
Might as well stay at home and lie down.
Xu Qingzhou helped Song Yao register a LOL account so that she and her little sister Ding Jiahui could play black games - novices playing against each other.
So, the first day of the holiday was spent in a mess.
October 2, 8 a.m.
It rained last night, but today is a sunny day. The golden sunshine shines in from the floor-to-ceiling window and shines on the corner of the desk.
In front of the table, there are sheets of paper covered with calculations.
Xu Qingzhou lowered his head, tapped the tip of his pen, and went through all the previous calculations in his mind, hoping to find loopholes.
[When Ap={n∈A:p|n} and P={p:p≤z} S(A,P)=π(x,z)S(A,P2)=π2(x,z) 】
[This means that when n≤Pz, there is: π2(Pz)=Pz2∏3≤p≤z(12p), and there is a constant M. 】
Ermeow yawned and wandered around the living room, rubbing Xu Qingzhou's trousers a few times. The two-legged beast ignored it and walked away alone.
The automatic feeding machine was empty and there was no food.
Cat life is tough!
"Hoo~"
Xu Qingzhou rubbed his temples and planned to rest for a few minutes.
Seeing Ermiao squatting in front of the feeding machine eagerly, he smiled and stood up.
Since using the feeding machine and cutting down on food, Ermeow has indeed become a little thinner than before. Although he still looks chubby, it would be best to lose weight. Animals are just like people, being fat is not good for the body.
"Scream twice if you want to eat." Xu Qingzhou hooked Ermiao's chin.
"Meow~"
Ermiao is very cooperative.
"Meow~meow~" It wasn't until Ermeow meowed twice more that he was worried about disturbing Song Yao who hadn't woken up yet, so he pressed the switch and put down a handful of cat food for Greedy Cat.
Watching the two cats enjoying breakfast, Xu Qingzhou took a cup of hot water and stood by the window to breathe in the fresh air, thinking about the next thing in his head.
The graduation thesis can be completed and defended by the end of this month. As for the tutor, he is now more inclined to Academician Chu Jiangfeng.
Thinking about it, Xu Qingzhou glanced at the manuscript paper on the table. The only troublesome thing was Polignac's conjecture.
Last time I was still lamenting that the proof process this time was very smooth and it felt like it was done in one go. But on the first day of October, I was hit in the head and stumped by the estimation of the exponential sum.
The calculated results are completely wrong.
The value is outrageous, and there is currently no solution.
How should I put it, it’s like a senior brother I met back then.
This senior fellow was working on an acoustic levitation project. After calculations using the boundary element method and checking using finite elements, he found that if properly designed, the instrument could levitate itself in the air and have a fairly high fault tolerance.
The doctoral supervisor came over for a spot check and only said one thing: Very good. If you have my suggestion, how about we stop this project and go directly to UFO research?
Xu Qingzhou is encountering this kind of problem now, and the calculated results can refute the index and itself.
Last night, under the eyes of school beauty Song, I went to bed at 12 o'clock.
At 6 o'clock in the morning, he got up again and continued counting.
Doing calculations is really like doi sometimes. If you don't do it, you will feel uncomfortable.
Bah~
Even the thought of this makes me sad.
Cursing himself secretly, Xu Qingzhou shook his head and cleared his mind. Song Yao was still sleeping, and he planned to wait for her to wake up before going out to buy breakfast.
At 8 o'clock, the community is already bustling.
Little old men and little old ladies were shopping for groceries, doing morning exercises, and some were already walking in the community. There were a lot of people, but there were not many young faces.
At this point, everyone is sleeping.
"The energetic old and the dead young."
After sighing, Xu Qingzhou turned back to the sofa and pulled out a stack of information from the armrest of the sofa.
After a few minutes, I heard the sound of tapping footsteps.
Song Yao was wrapped in pajamas, her hair was frizzy from sleep, and was hanging down on her shoulders, and she came out of the bedroom sleepily.
"Why are you up?" Xu Qingzhou put down the information.
"I'm just here to be my aunt. I'm not pregnant, nor am I disabled. I have to lie down all the time." Song Yao said with a snort.
Xu Qingzhou didn't argue. Girls, there are a few days every month where their moods fluctuate a bit.
Moreover, the girl whose voice was full of anger and harsh words just now has already plunged into his arms.
The two of them have been together for a long time, and they have seen each other look slovenly. Song Yao doesn't have the burden of being an idol like before, and she has to tidy up her hair before leaving the bedroom.
After all, we have all been honest with each other.
Song Yao hugged Xu Qingzhou, closed her eyes and felt the warmth coming from under the boy's clothes, and felt an inexplicable sense of security.
Xu Qingzhou trimmed the hair of the school beauty Song, gave her forehead a blow, and said: "You sit down and rest first, I will buy breakfast."
"I'll go with you."
"Okay."
Xu Qingzhou smiled and nodded, it would be good to go out for a walk.
15 minutes later, two young men appeared downstairs in the community.
In October, the atmosphere of autumn becomes stronger, the leaves turn from green to yellow, the road is covered with dead leaves, the air carries the fragrance of earth, and the puddles on the asphalt road reflect the blue of the sky.
On holidays, the vehicles and pedestrians on the road seem less busy, and everything seems quiet and peaceful.
The sun shines warmly on people, not burning at all.
Song Yao let Xu Qingzhou lead her, and she liked the feeling of just following along without thinking about anything, especially at this time.
He just kept holding her hand and squeezing it.
Both feet and hands, this guy has no normal hobbies.
Song Yao complained in her heart.
On this end, Xu Qingzhou felt the delicateness of his little hands, and his index finger made a circle in the palm of the school beauty Song from time to time.
Song Yao's hands are beautiful, her fingers are slender, white and tender.
Of course, the most important thing is that Song Yao is a little different at this time, gentle and gentle, which makes people want to tease her.
At the intersection, waiting for the red light.
Xu Qingzhou turned to look at the girl next to him.
Under the sun, a few strands of broken hair on the temples shone brightly. The sun shone from the side, and the long eyelashes left several silhouettes on her clean face. She did not wear makeup today, and a broken look appeared on her beautiful face. Beauty.
Xu Qingzhou couldn't help raising his hand and hooking her chin.
Song Yao blinked and made no move, as if she was thinking about how to hit this guy who was "teasing" her.
The silly look on the school beauty Song's face made Xu Qingzhou pinch her fair cheeks again out of nowhere.
Song Yao still didn't speak, looking at him lightly with an unkind look.
Xu Qingzhou was touched instead. At this time, Song Yao's face did not have the usual coldness on her face, and even her threatening gaze was poignant.
"There's something on your face." Xu Qingzhou stopped talking nonsense.
Song Yao's face was tense and her teeth were itching: "Xu Qingzhou, do you have a problem that makes people die if you don't bother them?"
"I can't help myself. The delicate appearance of School Beauty Song is so rare. Hiss~ I won't say it anymore."
"Is it still rare now?" Song Yao asked with narrowed eyes, twisting her hand around her boyfriend's waist.
"Rare."
"."
Song Yao curled her lips and was too lazy to talk to this person. She planned to wait for the past few days to take revenge.
At this moment, a familiar voice sounded behind the two of them.
"Xiao Xu, Xiao Song, you two, are you going out?"
"Aunt Jia."
Looking at the two people holding hands, Aunt Jia was stunned for a moment. Why haven't they seen each other for half a year? The state of these two children has completely changed.
The last time we met, Xiao Xu Yan was gone. This time it was Xiao Song?
"Both of you"
Aunt Jia's expression was complicated, and she thought to herself that this young couple, despite their usual seriousness, were still having fun.
"Aunt Jia, we have something else to do, let's leave first."
Xu Qingzhou noticed that Aunt Jia looked at them more and more strangely.
The two were crossing the road, and Aunt Jia and two other aunts had already caught up with them.
"Is this the tenant of your house?"
"Quite young."
"Yes, that young man has been in the news."
"Oh~ you bought the right house, the feng shui is good, look at your son, he has a successful career"
The two of them turned a corner and walked to a street with a breakfast shop. Behind them, the voices of the aunts were drowned in the wind.
(End of chapter)