Chapter 40 Chapter 39 "Nuclear Will-o'-the-wisps"

The uranium produced in Base X, the plutonium produced in Base W, and tens of thousands of tons of equipment were continuously transported to Base Y.The time has entered 1945, and the assembly of an atomic bomb is already being considered, but the amount of uranium or plutonium needed for a bomb is unknown, the relationship between the amount of uranium and the degree of enrichment is unknown, and how to determine the degree of enrichment is unknown— ——For a series of key problems, experimental physicists need to confirm the calculation results of theoretical physicists who are hundreds or even thousands of times different from each other.But how to do this experiment?The raw materials and objects of the experiment are uranium and plutonium, which look a lot like ordinary silver ingots.But they are not silver after all, but bombs with strong radioactivity and... thousands to tens of thousands of tons of "equivalent"!

No matter in theory or in practice, uranium or plutonium that reaches a certain volume and weight will be bombarded by "traveling neutrons" that are ubiquitous in the atmosphere and cause a natural nuclear explosion-this volume and weight is called "Critical value".The explosion mechanism of the atomic bomb is exactly that two or more nuclear charges that are smaller than the "critical value" suddenly combine together to be greater than the "critical value" and cause a nuclear reaction.Ding Jieqiong calculated the neutron scattering angle and the number of neutrons in the uncontrollable chain reaction, and determined that the "critical value" of uranium-235 was 50 kilograms, and that of plutonium-239 was more than 10 kilograms.Wrapping neutron reflective material around the nuclear charge can greatly reduce its "threshold".Ding Jieqiong participated in the material screening and summed up the calculation formula for the relationship between the type of material, thickness and "critical value"...

In short, the "critical value" has become a key issue and the core of the entire Alamos theory.Physicists have dozens of calculations for this.Which result is correct must be proved by experiments.Professor Ding Jieqiong was the first to declare his experimental design and it was approved soon.Uranium is far less radioactive than plutonium.Among the three isotopes of natural uranium, uranium-235 has the lowest radiation energy.Based on this, female scientists believe that experiments can be carried out directly with uranium-235 "bare balls".She is the leader of a group in the experimental physics room, and has the power and convenience to borrow uranium blocks.So she borrowed sixteen uranium nuggets of various sizes and shapes.But then she overstepped her authority: Alamos strictly forbids individuals to do experiments alone, let alone hold a uranium block that is easy to "join" with other uranium blocks to reach or exceed the "critical value"-all of which Ding Jieqiong violated up.Fortunately, Alamos had too many violations, and the Yankees were usually extroverted and careless; as long as it was not a blatant and well-documented espionage, they were generally ignored.In addition, most people pay attention to and respect this beautiful and lonely woman. They all know her special relationship with General Perry and Dr. Olmhos, and they also saw her buried in the laboratory after she came to Alamos. Get to know how incredibly hardworking and creative she is.Everyone agreed to try to minimize disturbance to her.This has provided good conditions for the work of female scientists and the experiments in front of them, while ignoring the extreme danger of this experiment.

In order to be quiet, and to avoid radiation injuries or other accidents, Ding Jieqiong decided to work at night without an assistant.Today is the first night.She drove to the outside of the laboratory building and stepped into her laboratory at midnight.This kind of experimental project has never been considered or carried out before, so there are no "robots" and "manipulators" in the laboratory, and there are not enough and qualified automatic control equipment.Female scientists can only start to operate with simplicity.Her work is often exposed to radiation.But this time the radiation source is completely exposed, the distance is the closest, and the radiation intensity is the highest.She placed monitoring instruments around, turned on the power, and inspected them one by one; then she put on a protective helmet, as well as armor-like rubber gloves, a rubber blouse, and a rubber apron—this set was originally for "thorium roasting" of. "Baked thorium" is scientists' colloquial term for bombarding thorium with neutrons.Thorium is radioactive, and radioactive uranium 233 will also be produced in the experiment, and the neutron beam itself is a kind of radiation—so much radioactivity, and this "helmet" and "armor" have low shielding functions, but are completely thick and bulky...

In the world of physics, and in the entire scientific world, to be honest, Ding Jieqiong looks down on most of her male colleagues.But, not now, she began to envy them.I have seen men wearing this "outfit" weighing fifteen kilograms many times before, but I have never seen anyone so out of breath!She took a photo on the reflective stainless steel plate and found that she had been "unrecognizable". The original lady was gone, and she became a deep-sea diver or a "Martian"!She moved clumsily, breathing hard, and the lens in front of her was covered by water mist from time to time...

Uranium is extremely heavy - this can also be seen from its atomic number and atomic weight.Even a small piece of uranium will be heavy; especially the finely polished "uranium bare ball" is very easy to slip and fall out of the hand.When doing this kind of experiment in the past, several young men felt nervous and struggling to cooperate, but today it is actually a woman doing it alone!Ding Jieqiong is not a "weak woman", but a woman is a woman after all.She felt a little regretful and scared, but she couldn't stop, and she didn't want to stop.She braced herself and forced herself to be calmer, calmer.After that, she finally grabbed a screwdriver in her right hand and started to work—she didn’t know what the screwdriver was for, but she just felt like an ancient warrior, holding something in her hand would give her a little more sense of security.She carefully took out two hemispherical uranium blocks from the container, let the "steel claws" at both ends of the guide groove firmly grasp them, set the speed, and let them slowly close together.The female professor held her breath, closely observing, recording, and taking pictures; once a chain reaction occurs, the two "hemispheres" must be separated immediately when the "critical point" is reached at the first moment...

Her experiment was successful.Whenever the two hemispheres are very close, blue light flickers in the air near the channel and around her body-this is the "ion gas" produced by the ionization of air atoms caused by violent radiation, which is called "nuclear ghost fire" by physicists. ".This shows that criticality is approaching, and a chain reaction begins to occur, that is, a nuclear explosion is about to occur.It may be difficult for later people to imagine that the most advanced atomic energy science ever used such a primitive operation method!The female scientist was sweating profusely as she hastily separated the two hemispheres.Then check the recording tape on the counter and the readings on all monitoring instruments, and prepare for the next experiment...

Ding Guqiong forgot to check the time.The success of the first trial excited her.She had sixteen uranium nuggets of various shapes and compositions, and she went on to a second and third experiment.Suddenly, the "steel claw" at one end of the guide groove failed, and a metal uranium ball it was holding fell out; apparently at the same time, the guide groove tilted or some kind of magnetic induction occurred, and the uranium ball began to slowly roll along the guide groove, heading towards the other side. The uranium ball at one end approached.The smoothness of the guide groove and the uranium ball has reached the highest level, so that the rolling is unimpeded and extremely smooth...

The female scientist didn't expect this to happen, and was stunned for a moment, unable to react.The blue light started to flicker again, and the flicker became stronger and stronger, and there were "nuclear will-o'-the-wisps" dancing and jumping all over the room!At the same time, the clicking of the counters stopped, the red lights stopped flashing, and all monitoring instruments were paralyzed—that is, the intense radiation caused by the chain reaction was far beyond the tolerance of all instruments.Seeing this terrible scene, Ding Jieqiong suddenly seemed to have fallen from an ice cellar, and his mind went blank!In an instant, she seemed to wake up, and rushed forward, trying to lie on the guide trough to block the rolling of the uranium ball...

At the critical moment, the female scientist was pushed away!A man with agility took a few steps forward and placed a long and thick wooden bar on the guide groove stably, blocking the falling uranium ball in time.The man was sweating profusely, gasped for breath, and stared at the uranium ball intently; after several seconds, he held the wooden bar tightly with both hands, pushed it back against the uranium ball, lightly pushed... the blue light like will-o'-the-wisp disappeared, The uranium ball returns to a safe position.The laboratory was still brightly lit and extremely quiet, as if nothing had happened.

It was a man, tall and thin; twenty minutes later, he put all the uranium balls back into the special container with steady movements.After that, he took a deep breath and turned around... Ding Jieqiong was leaning on a wooden chair, limp and unable to move.She struggled to take off the "helmet" and looked at everything in front of her with a dazed expression, pale face, and trembling all over.Finally, she planted her head and face on the chest of the opponent who was getting closer and wider, and shouted tremblingly: "Ah, Aum!"