Reactors that use light water (HO) as a neutron moderator are called LWRs; Heavy water (DO) is called a heavy water reactor.

In addition to the two, graphite that uses graphite as a neutron moderator is called a graphite pile.

Ordinary water HO is light water, while heavy water is different at the molecular level, as the name suggests, heavy water is heavier than ordinary water.

Hydrogen has three isotopes in nature, namely deuterium, deuterium, and tritium. The light water molecule contains two hydrogen atoms, while the heavy water molecule is replaced by two deuterium atoms.

So these two types of water are fundamentally different, and the difference in molecular weight makes heavy water 11% heavier than light water; Although heavy water is not toxic, it cannot be used by plants and animals to nourish all things.

The reason why the joint team of Imperial Gezhi University and Suncheon University of Technology has encountered a setback is that the understanding of neutron moderators and chain reactions is not sufficient, but they are urged to produce results as soon as possible, so it is inevitable that they are quite hasty.

Generally speaking, LWRs are more convenient because they use common water as neutron moderators, but the abundance of U-235 required to maintain a stable chain reaction is 3%~5%, and it is difficult to maintain stability below this concentration.

Zhou Changfeng felt that the mentality of the upper echelons of the Ming Dynasty was not good at all, and it was not rebellious to seize the time and be down-to-earth.

Moreover, the nuclear program began very quickly in 39 years, and there was plenty of time, so it was completely possible to take it relatively calmly.

"Mr. Zhao, it is definitely not possible to rush the work in such a hurry, everything is difficult at the beginning, and the basic experiment must be solid." He muttered: "I will give honest feedback after I return to Beijing, don't worry about being urged." ”

Zhao Zhansheng, who had a look of embarrassment on his face, said with emotion: "Hey, thank you so much, and now it is really ...... to have a rational person like you Luckily, it's not what it used to be. ”

Zhao Zhansheng is quite nostalgic for the Ming Dynasty from the 10s to the 20s, when although many aspects were not as good as now, everything was thriving, and there were more technocrats than now, and things were done in an orderly manner, and almost no indiscriminate interference.

Later, the two discussed a series of matters related to the Golden Crow plan.

Zhou Changfeng suggested that graphite should be used directly as a neutron moderator, and graphite reactors should be built directly in one step.

"Yes, graphite is also an excellent decelerant, but preliminary calculations show that if it is to be used to build piles, it must be very pure." Zhao Zhansheng looked at the sunset over the mountains in the west in the distance, "Heavy water is also very scarce. ”

The impurity content of graphite used in the construction of reactors should not exceed 50 parts per million, and it is said that the Germans were forced to use heavy water as a neutron moderator because they could not obtain high-purity graphite.

Heavy water was discovered only six years ago, and Norway is the only country in the world to build a heavy water chemical plant called Vimok – which uses the abundant electricity of the Barron Hydroelectric Power Station.

However, the annual production capacity of the Vimok plant is only 1,300 kg – a tenth of what is needed to build a working heavy water reactor.

Therefore, the historical special operation raid of the British on the Vimok factory was practically unnecessary, and the Germans simply did not have enough heavy water to save the necessary heavy water.

"At that time, I was still overconfident when I had a meeting, and this raw material is really rare." Zhao Zhansheng, who was worried, was a little discouraged.

Zhou Changfeng can understand the physicist's worries, because in his eyes this is an insurmountable mountain, it seems that he knows the true face of Lushan, but when he gets closer, he finds that the road up the mountain is as difficult as climbing to the sky!

"It's not your concern." Zhou Changfeng patted him on the shoulder and said with a smile: "You seem to underestimate the significance of this thing, this is something that can make the emperor, the imperial court, and the military department gather together to discuss secretly." ”

"I'm afraid that even the strength of the whole country will be in vain."

"Isn't it? If he had held this mentality before, Zhao Shiling would not have achieved today's achievements. ”

"That's not the same thing." Zhao Zhansheng smiled bitterly: "In the past, I was not afraid of setbacks and didn't care about failure, because at most it was a matter of one person or a few people, but now it is different, and it costs tens of thousands or hundreds of thousands of dollars at every turn...... Presumably, Zhou Zhizhao also understands, and the burden on his heart is heavy. ”

"There are some things that you can't live without even if you're hungry, and it's too late when the knife is on your neck." Zhou Changfeng looked up at the sky, crossed his waist and said, "At least now Da Ming is not to the point where he can't afford to eat, right?" ”

Both of them were silent, and the scene fell silent for a long time, except for the shouts of people rushing back and forth in the distance behind them.

After a while, Zhao Zhansheng turned his head sideways and asked: "Zhou Zhizhao, I have always been a little curious, if there is a mistake in your leading army, it will lose the troops and generals, and the lives of the sergeants will melt like snowflakes." Won't you have a psychological burden? ”

Zhou Changfeng on the side couldn't help but smile, "It varies from person to person, those cold people don't have this kind of burden, but most generals will still have it to a greater or lesser extent." Well, I've always believed that I can do my best, and that someone else will only get worse, so ...... It's not too much of a burden. ”

"Yes." Zhao Zhansheng thought for a moment and said calmly: "Being a person should be confident, and non-confident people can't achieve great things." ”

Relief is relief, and Zhou Changfeng also realized that Daming's nuclear program should indeed not follow the path of implosion plutonium bomb by wishful thinking.

Zhu Lingjing's thoughts at that time were probably the most appropriate, no matter what, she couldn't joke with the fate of the country.

Although the principle of gun-type uranium ammunition is simple, it is too troublesome to enrich low-abundance uranium ore, and the amount of work is beyond imagination.

Exploration for uranium is already well underway, but several of the identified uranium deposits are of average grade sandstone or quartzite.

If you want to reduce the amount of work, you must choose some natural uranium ore with good grade and high abundance.

Zhou Changfeng was annoyed that he didn't know anything about this before the crossing - he knew that there were good-grade uranium mines in the north and south of the river, but he didn't know which province it was.

I'm afraid we have to look abroad, see where there are abundant natural uranium mines, and try to get a batch back before the major powers pay attention to it at the official level.

"Master Zhao, it's time for dinner, let's ......"

Just as Zhou was about to invite Zhao Zhansheng to have dinner with him, a communications officer hurriedly came.

He bowed his hand and said: "Zhou waits for the edict, there is a new military situation, half an hour ago, at eleven noon Berlin time, the million German troops in France launched a new offensive!" ”

It was a matter of time, so Zhou Changfeng was not surprised at all, "What about the other news?" How did the Renault government react? ”

"There is no definite news yet, but the legation seems to say that those dignitaries have already prepared their planes."

The Ming Dynasty had not yet recognized the French Democratic Commune, so the legation in France still followed the remnants of the Third Republic to Bordeaux.

Although it had suffered a lot of fighting and non-combat attrition in the process of advancing before, if it had been forced to attack, the German army would probably have been able to end the struggling Third Republic more than a month ago.

In addition to the need for military reinforcements, political considerations were also an important factor in the suspension of the German offensive.

Ernst wanted to take a clear look at the attitudes of the countries through the Reynaud government in southwestern France, and to assess the wishes of the French – and especially the French Democratic Commune.

Now, with both military and political needs complete, the offensive is about to resume.

If France was compared to a flashy brick house, easily breached by the German Society, then the remnants of the Third Republic, now cowering in the southwest, are just the ruins of this brick house.

The German 13th Motorized Rifle Division, which was at the spearhead of the attack, captured nearly 10,000 people from the French 67th Infantry Division at a small cost of 8 killed and 29 wounded.

And this was only the tip of the whole front, and the remnants of the Third Republic collapsed like dominoes that had been toppled.

Except for a few die-hard loyalists, most of the French generals still wanted to find a better way out for themselves.

But this is no longer the case, in the past, the armies of the European powers were at war, and the generals who led their men to fight bravely and tenaciously were respected and courteous even if they were captured.

However, the German army now regards this behavior as an evil stubborn resistance, and the longer it persists, the more casualties it will inflict on it.

Once the captured high-ranking French generals were designated as "Reaktionr" by the German army, they would probably have to undergo a long period of ideological reform in prison.

The Germans did not do it well, but the French Democratic Commune, which was also French, was really harsh.

Paris, for its part, demanded the "ruthless extermination" of the recalcitrant reactionaries, and any hostilities and acts of resistance were "betrayal and murder of the French people."

In order to forcibly stabilize the demoralized troops, the French gendarmerie has become more and more harsh in enforcing the law over the past two months, often executing deserters and complainants without formal trial, and the French soldiers hated them to the core.

Now these gendarmes, after being captured by the Democratic Commune Army, were quickly tried and convicted by mobile military courts at the front, and then gathered to be quickly executed using heavy machine guns.

In short, this made the discouraged French army completely ineffective, and now the generals have to look ahead and weigh it carefully when they give the order to hold on.

There have been many French generals who have refused to sign any military orders, because they are responsible for signing them.

The Renault government, which had already left a way out, did not hesitate to flee immediately, and the long convoy stretched for nearly a kilometer.

Although they stopped and stopped on the way due to the obstruction of the guerrillas, they finally managed to reach the Gulf of La Tateste and moved to the North African colony of Morocco on a warship.

Within three days, hundreds of thousands of French troops had collapsed, with negligible casualties on both sides, and it was more of a marching exercise than a battle.

7 September: "The vicious invading and rebel armies have begun to attack!"

September 8: "Melpan has fallen! The enemy is advancing!"

9 September: "The Germans are crossing the Doddogne."

10 September: "The glorious liberators and insurrectionists enter Bordeaux."

The dust of war in France has settled, and in the vast Atlantic, the game of cat and mouse is still going on......

"Comrades! The Reynaud government has fled to Morocco, and to celebrate the fall of the incompetent and decaying Third Republic, those who have completed their shifts can receive wine and barbecue in the canteen! ”

The battlecruiser Franz continued to cruise the North Atlantic route, single-handedly inflicting heavy damage on the HX27 flotilla, and the War Council instructed the Ministry of Defense to award the Knight's Cross to the officers and men of the Franz.

As the name suggests, this is a kind of medal established by the German Society to recognize collective honor.

In fact, in the early days, the German Society tried to abandon the traditional Iron Cross, and they set up a five-pointed star, five-sided medal of honor, but the response was mediocre, and the soldiers were not very interested in it, so after the twenties, it still returned to the traditional shape that was more deeply rooted in the hearts of the people.

The Iron Cross issued by the German Society should actually be called the Bronze Cross, because it uses pure copper instead of cast iron, and the outer frame has a metallic dark red color. However, due to the high cost, the Ministry of Defense is also considering switching back to cast iron.

"Comrade Captain, the lookout post found a fleet 17 kilometers away, in direction 230, estimated to be light ships."

Major General Hubert picked up his huge binoculars from the side and looked carefully in that direction.

The bridge was not as far away as the lookout post on the mast, so Hubert saw only tiny masts and chimneys at first.

The German sailors thought they had caught another big fish, but to their surprise the fleet did not contain any merchant ships.

"Strange, no merchant ships in sight."

"Those destroyers are not in position for the escort fleet."

"Did you see that? That's not the X flag, it's the American flag. ”

The Franz encountered four destroyers from the 23rd Destroyer Detachment of the U.S. Atlantic Fleet, who were ordered by the Admiralty to search the North Atlantic route for traces of the German Destroyer Fleet.

The two sides soon discovered each other, and considering that the United States was still neutral, Hubert simply ordered to ignore it and avoid these menacing American destroyers.

However, the four destroyers did not persevere, but gradually increased their speed and met them.

The two sides began to communicate with each other by semaphore, and the Franz's radio listening team suddenly reported that the destroyers were transmitting the current coordinates in clear code.

"These hateful Americans!" The annoyed navigator scolded.

Major General Hubert then ordered: "Increase speed, full speed; Adjust the course to 195 and avoid them as quickly as possible. ”

The slender Franz made an arc in the unusually calm Atlantic Ocean and turned to the southwest.

The Franz, which was hit by an aviation torpedo, could only reach a top speed of 29 knots, while the maximum speed of the four US destroyers could exceed 35 knots, which was not a class at all.

As a result, the two sides became entangled in this way.

Because the U.S. patrol fleet lifted the radio silence, the Germans could cleanly hear the communication of the four destroyers in the frequency band.

The detachment's flagship, the Sims (DD-411), ordered the remaining three ships to encircle the Franz together, and finally stuck it in the middle in a formation of two from the left and two from the back.

"This is a deliberate act of hostility, Captain!"

"The Britons must already know where we are, and the Athletic and Fury are likely to come over."

A staff officer calmly elaborated: "From the intercepted radio signals, it can be estimated that the Athletic God last appeared in the eastern section of the route, which may be only 550 kilometers away from us. ”

(End of chapter)