Reborn and become a Great Scientist

Chapter 348 87 How to fix deuterium atoms

Chen Muwu is going to do two experiments at the particle accelerator this time. They are the experiment of bombarding deuterium nuclei with deuterium nuclei that Eddington, who is waiting outside the preparation room, wants to see the results; and the experiment that he really wants. The experiment in which deuterium and hydrogen nuclei collided.

So this time he chose to fill the deuterium gas produced by the vaporization of liquid deuterium into the particle generator that had been emptied of hydrogen. He planned to follow the same pattern and turn the deuterium gas into plasma, and then pass it through voltage screening. The nuclei with positrons were photographed and used as the source of particles in the two experiments.

Filling the particle source with deuterium gas can be regarded as the simplest step in the entire experiment.

After completing this work, Chen Muwu began to stay in front of the particle accelerator in a daze, while Eddington stayed in the experimental preparation room, observing Chen Muwu in a daze through the glass.

After a while, Eddington who was waiting outside was already a little impatient. Chen Muwu, who was wearing an electrostatic isolation suit inside, finally made his next move.

He did not choose to control the particle accelerator in front of him, but closed the valve of the particle source and walked out.

Eddington asked very puzzledly: "What's going on, Chen?"

Chen Muwu had a wry smile on his face: "I think today's experiment will not be completed unless something unexpected happens." "

"Why? What happened? The machine is broken?"

Eddington, who was still very puzzled just now, immediately became very shocked after hearing the answer.

"It's nothing serious. There's something wrong with me. I wasn't prepared enough for the experiment, and I thought operating the particle accelerator was too simple."

"Aren't you the designer of the particle accelerator? Why don't you even know how to use this machine! Then quickly find someone who can operate this machine. The meaning behind the experiment we are going to do is great. One point for one Don’t waste even a second!”

"Professor Eddington, the two people who are best at operating this machine in the entire Cavendish Laboratory, one of them is in the United States, and the other is in Germany or the Soviet Union, and they won't be able to come back for a while. "

Seeing the two eyebrows above Eddington's eyes getting tighter and tighter, and his expression becoming more and more urgent, Chen Muwu finally stopped pretending:
"But even if they don't come back, I can solve this problem. Because the problem is not that I don't know how to use this accelerator - of course I will use it -, the real reason is that we have insufficient preparation of experimental materials."

Eddington became more and more confused by what he said: "You said you wanted deuterium gas. The British Air Company sent liquefied liquid deuterium over night. And there is a ready-made particle accelerator here. What experimental materials are still missing? What experimental materials can we lack?”

"Deuterium deficiency..."

"Deuterium deficiency?"

After hearing the reasons given by Chen Muwu, Eddington finally couldn't help but explode.

Even if Chen Muwu doesn't want to do an experiment today, he can fool a layman like himself if he can choose a slightly more reasonable excuse.

As a result, he actually said that he was lacking deuterium, even though the liquefied gas tank sent by British Air Company was now placed in the corner of the preparation room!

Also, if there is no deuterium gas, what is it that he just filled into the particle source?
I used to really like Chen Muwu. Who would have thought that he would become like this now?

"Professor Eddington, wait until I finish!"

Before Eddington exploded, Chen Muwu quickly interrupted his spell-casting chant.

Because he knew very well that Eddington had two sides: he was an elegant and easy-going British gentleman, and he was a reckless man who beat people up without mercy.

If the other party couldn't control himself and hit himself in the face with a fist like the editor of the "Journal of Philosophy" did last time, then Chen Muwu would not be able to bear the consequences and walk away.

"When I say lack of deuterium, I don't mean that there is a lack of liquid deuterium or deuterium gas, but that there is a lack of a way to fix deuterium atoms on the target."

Han Changli Gong once said, "The work is accomplished by hard work, but wasteful by play; the success is achieved by thinking, and the failure is caused by following."

Chen Muwu's bad luck this time was due to "Huang Yuxi".

He indeed led Zhao Zhongyao and Cockcroft to build the world's first particle accelerator, and also guided them to complete the first nuclear transmutation experiment in human history by using accelerated hydrogen nuclei to bombard metal targets. .

But after that, Chen Muwu began to act as a hands-off shopkeeper. Basically, he handed over all the big and small things about the particle accelerator to the two of them.

For some time, Chen Muwu had only known the researchers in the Cavendish Laboratory, and with the help of the two of them, they had done many bombardment experiments with this particle accelerator.

He had a general impression of these experiments, so he was able to quickly find the cloud chamber trajectory photographic film of using accelerated protons to bombard hydrogen atoms from the data storage room a few days ago, and show Eddington the collision of two hydrogen nuclei. Together, deuterium nuclei or helium-2 nuclei will not be produced.

But if he asked further about how those experiments were conducted, Chen Muwu began to become unaware.

He had just stood in front of the particle accelerator when he discovered such a serious problem.

The targets used in particle accelerators before were made of metallic elements or non-metallic crystals. The targets made of these were all solid.

But what he wants to use as a target this time is deuterium, which always exists in the form of a gas at normal temperatures and pressures. How can he fix it on the target?
Chen Muwu stood in the laboratory for a long time and could not figure out a solution to this problem.

He had no choice but to leave the room where the particle accelerator was installed, take off his electrostatic isolation suit and return to the experimental preparation room, where he explained the problems and troubles he encountered in detail to Eddington.

Even though what Chen Muwu said was reasonable, Eddington was still a little bit reluctant when his temper was rising.

"Didn't you explain to me before that because there are two electrons in the hydrogen molecule, the charge can still be conserved in the end? Isn't that just the hydrogen gas used? Why can't it be changed after replacing it with deuterium?"

"Professor, that may be because I didn't think carefully at the time. I thought hydrogen could be used as a target, and I didn't think about the depth of the particle accelerator at all."

Eddington actually thought of hydrogen, and he also thought of the cloud chamber photographic plate that Chen Muwu found for him a few days ago.

"Chen, again that time, didn't you find a photo of protons bombarding hydrogen nuclei? How did they do the experiment?"

"This...I can't tell you clearly."

Chen Muwu was embarrassed when he was caught.

Eddington was angry, but it was hard for him to vent in this situation. After all, the experiment was important.

If Chen Muwu hadn't suggested to the Times reporter that nuclear fusion in the sun could exist in new forms, he would still have a pessimistic attitude towards this idea.

Moreover, Dr. Chen's two assistants are not in Cambridge now. If he wants to operate this experiment on the particle accelerator, he has to be the one.Of course, he was still a little angry in his heart, but Eddington quickly adjusted and comforted Chen Muwu softly: "Then let's go through their papers, maybe we can find a solution."

When Eddington left the particle accelerator laboratory, he was no longer as cheerful as when he arrived.

On the way to the Cavendish Laboratory, the two looked at each other in silence.

Chen Muwu quickly found a recently published paper on using protons to bombard a series of elements from the data room, and also found the part about bombarding hydrogen nuclei in the paper.

Sure enough, just like what he realized when he stood in front of the particle accelerator and meditated, what they added to the particle accelerator during the experiment was not hydrogen gas composed of hydrogen molecules, but hydrogen atoms fixed into the crystal.

After seeing this idea, Chen Muwu took Zhuge Liang seriously.

He complained secretly in his heart that he should have thought of this a long time ago.

In order to test whether beryllium rays are gamma rays, the Curies used paraffin blocks rich in hydrogen atoms in order to increase the probability of collision between beryllium rays and hydrogen atoms in paraffin, making it easier to remove protons from the paraffin. Type it out.

He himself also used this method two days ago. Why did he forget this method today?

Of course, in the paper that bombarded hydrogen atoms with protons, paraffin was not used, but inorganic compounds were chosen, such as ammonium chloride NHCl or ammonium sulfite (NH)SO.

For Chen Muwu, this is a good option.

Because although paraffin is rich in hydrogen atoms, those atoms contain only one proton of protium. Chen Muwu could not find paraffin containing a large number of deuterium atoms.

The inorganic compounds are different, although deuterated ammonium chloride NDCl or deuterated ammonium sulfite (ND) SO, which are rich in deuterium atoms, cannot be found in natural minerals.

But now that the most critical material, liquid deuterium, is available, these inorganic compounds can be synthesized on a small scale in the laboratory.

After reading the paper, Chen Muwu expressed his thoughts to Eddington: If he wanted to do the experiment of deuteron bombardment of deuterium atoms, he must first find a chemical laboratory to use deuterium gas to prepare a portion of deuterated ammonium chloride. NDCl.

Chen Muwu finally chose deuterated ammonium chloride instead of deuterated ammonium sulfite, not because the former ranked higher in that paper, but because it was more convenient to make.

The volume of nitrogen N and deuterium D is one to three. At a high temperature of about [-] degrees, using an iron catalyst for catalysis, it can become deuterated ammonia ND.

This method is used to synthesize ammonia in industry. Although it is time-consuming and laborious to replicate it in the laboratory, deuterated ammonia can still be synthesized.

After having deuterated ammonia gas, it is time to make another material, which is deuterium chloride.

This is simpler to make than deuterated ammonia. You only need to let the deuterium burn in chlorine to produce a pale flame. Until the yellow-green color in the gas collection bottle gradually disappears, deuterium chloride gas is produced.

Then mix deuterated ammonia gas and deuterium chloride to produce a large amount of white smoke, which is the solid powder of deuterated ammonium chloride.

Chen Muwu has never been exposed to chemical experiments in his two lives, and these simple knowledge can be recalled through his only remaining high school memories.

What else needs to be done to check the purity of hydrogen before burning it? Collect a test tube and hold the gas nozzle downward toward a lit alcohol lamp. A sharp popping sound means it is impure, and a weak popping sound means it is pure.

The knowledge was not forgotten, but he was not sure how confident he could be in using it.

Chen Muwu also felt that it seemed difficult to collect the smoky deuterated ammonium chloride product after mixing deuterated ammonia gas and deuterium chloride.

It is better to pass these two gases into water to become deuterated ammonia water and deuterated hydrochloric acid, and then mix the two solutions, and you should be able to obtain an aqueous solution of deuterated ammonium chloride.

Crystallizing deuterated ammonium chloride from an aqueous solution should be easier than collecting the solid powder that forms after combustion.

But if you make an aqueous solution, you have to face another problem.

From the synthesis of ammonia to the combustion to obtain hydrogen chloride, he always ensured that all hydrogen atoms used were deuterium.

In the same way, if the water required to make an aqueous solution is ordinary distilled water HO, the deuterated ammonium radicals will be hydrolyzed in the water, and the ND can be ionized with deuterated ions D and deuterated ammonia ND, and release energy at the same time.

Deuterium ions can combine with the weakly ionized hydroxyl radical OH in water to become semi-heavy water HDO.

As deuterium atoms enter the water through hydrolysis, the same number of hydrogen atoms enter the ammonium radicals.

In this way, the crystals crystallized from the deuterated ammonium chloride aqueous solution are most likely not pure NDCl, but NDHCl, which will be doped with some protium atoms.

If you want to keep it pure, you cannot use ordinary distilled water when making aqueous solutions, but heavy water DO should be used.

But there was no heavy water in the Cavendish Laboratory. They only had liquid deuterium sent by the British Air Company.

If I had known what kind of liquid deuterium to buy, I should have just bought heavy water.

Whether it is electrolyzing heavy water or throwing a piece of potassium into heavy water, deuterium gas can be easily produced.

But this is just a thought. Although Chen Muwu discovered deuterium in advance and discovered heavy water soon after, the world's first heavy water factory had begun construction at this time, but it does not yet have the ability to produce heavy water.

After thinking about it for a long time, Chen Muwu finally decided to choose ordinary distilled water instead of thinking about whether it was heavy or not.

He did not even intend to prepare deuterium chloride himself, but generously used ready-made hydrochloric acid.

Anyway, ordinary distilled water has been used, so it doesn't matter whether there is one hydrogen atom or two hydrogen atoms in the ammonium chloride molecule produced.

As long as he ensures that he can use nitrogen and deuterium to produce deuterated ammonia, so that the resulting ammonium chloride crystal contains deuterium, and successfully fixes the gaseous deuterium into solid deuterium atoms, suitable for being used as a target in a particle accelerator, then All is well.

What's more, he not only bombards deuterium atoms with deuterium atoms, but also bombards hydrogen atoms.

This target has both hydrogen isotopes, so it might be possible to kill two birds with one stone.

(End of this chapter)