A big country of aerospace with black technology

The successful completion of the spacewalk brought the space station construction plan a big step forward.

This can be regarded as the most important content of this space mission.

The Shenzhou spacecraft enters space on its seventh day.

The space vegetables in the orbital module laboratory have grown to a height of nearly five centimeters.

According to the agricultural experience above the ground, this has reached the harvest standard.

"The finished products in the metal crystal growth furnace have been packaged."

Nie Haisheng gently loaded the finished experimental product into the cargo box and fixed it in the cabin of the return capsule.

These hard-won and expensive experimental products will ride on the return capsule with them and return to the earth together.

"How is the packaging of space vegetables going?"

Compared with solid metal products, packaging of vegetables is more difficult.

Because these little guys are even more fragile.

In addition to those fast-growing vegetables, there are also some seeds that are very precious.

Endangered plant seeds from Sanqing Mountain have also been cultivated and germinated in space.

They now have to carefully put these very weak little guys into small boxes according to the training they received before.

Then it is padded with cushioning cotton and stuffed into the cargo hold of the return capsule.

After packing all the goods, the two made a final inspection of each system in the spacecraft.

Especially critical energy systems.

The solar panels work very efficiently and are still working tirelessly.

It will ensure that the equipment on the spacecraft can maintain operation after the astronauts leave.

After the two completed all their work, they had their last meal in space.

There is still a lot of leftover food prepared in advance.

In addition to the conventional various staple foods and dishes, the remaining items are actually various types of desserts and freeze-dried fruits.

"Let's take a photo as a souvenir!" Fei Junlong said after completing a series of tasks.

There was still a little bit of free time before they returned.

The two used the camera inside the spacecraft to take a very beautiful photo with the blue earth in the porthole as the background.

After the filming is completed, it is transmitted back to the earth through a relay satellite outside the spacecraft.

They also let everyone on the ground see their joy.

The accompanying relay satellite uses the latest communication technology.

The amount of synchronously transmitted data is increased by an order of magnitude.

The most intuitive feeling is that now the ground command center can even have real-time video connection with the two people in the spacecraft.

Before this, communication between heaven and earth had to be carried out with the help of communication satellites, although video calls were also possible.

But this requires coordinating a low-orbit communication satellite before the call, which is not only time-consuming and labor-intensive, but also troublesome.

Nowadays, their situation can be seen on the ground at any time through the cameras in the cabin.

Real-time communication is also possible, and the efficiency is much higher than before.

Of course, limited by the current technical level, high-resolution real-time video is not yet possible.

The resolution can only barely reach 1080p. It’s not that the resolution of the camera cannot be reached, but that the communication transmission speed cannot be reached.

Adding resolution to the top increases the requirements for transmission speed exponentially.

In fact, this problem can also be solved by coordinating several low-orbit communication satellites.

However, everyone has always believed that the current resolution is acceptable, so there is no need to waste manpower and material resources on this matter.

The two astronauts completed their last mission in space and closed the door of the return capsule.

He sat quietly on the seat of the return cabin.

Compared with the first space mission, this time's seat has greatly improved the buffer mechanism.

This allows astronauts to no longer bear such a large impact during the violent deceleration stage.

After reaching the scheduled return time and obtaining approval from the ground command center, the two disconnected from the spacecraft in accordance with the operations learned during training.

The attitude adjustment engine on the return capsule officially started working.

The angle was fine-tuned again and again so that the return capsule could be aligned with the return site.

In a short period of time, the return capsule rushed into the atmosphere at an extremely high speed.

The material on the outer wall of the return cabin takes away a lot of heat during the intense friction, protecting the safety of the people inside the cabin.

The material sublimates and vaporizes, creating a thick layer of high-temperature plasma on the surface of the return capsule.

So much so that electromagnetic waves cannot penetrate these plasmas.

The return capsule began to experience the most terrifying black barrier area in the entire process.

Disconnected from the ground.

At this stage, because only the breathing and heartbeats of the two people in the cabin can be heard, the psychological demands on the astronauts are extremely high.

No matter how much training you do on the ground, it is difficult to offset such inexplicable terror.

Fortunately, the two of them were able to relieve their inner emotions by chatting with each other.

The speed of the return capsule is extremely fast, even faster than many missiles.

The black barrier area only lasted for a few minutes.

The return capsule has reached the northwest sky at this time, not far from the planned Amugulang grassland.

The large electronic scanning radar on the ground has been turned on and is ready to find the return capsule.

The helicopter brigade also started to start their engines, their iron wings spun, and they began to cross the grassland.

The convoy set off early and entered the grassland.

Six minutes later, the main parachute cover of the return module opened, and the huge parachute instantly bloomed in the sky.

The speed of the return capsule also dropped immediately.

The astronauts sitting inside can feel the strong impact even with the cushioning of the cushion seat.

Fortunately, the two of them have excellent physical fitness, and the space mission lasts only seven or eight days, which is not very long, and has not had a major impact on their bodies.

Four minutes later, the return capsule threw out its heat-emitting bottom and took a step closer to the ground.

Five minutes later, it was only tens of meters above the ground. After the gamma altimeter detected it, the honeycomb recoil engine was controlled to ignite, and the speed of the return capsule finally dropped to the minimum.

The two of them felt two bumps under their buttocks, and then there was no more movement.

Knowing that he was finally back on the ground, his hanging heart finally relaxed.

Ten minutes later, the first to find them was the helicopter brigade in the sky.

With the help of search personnel, the hatch was finally opened.

Fei Junlong climbed out of the return cabin first, and then with his help, Nie Haisheng also returned to the cabin and walked out.

As aerospace heroes, they basically don't have to think about too many things after arriving on the ground.

Someone will take away the return capsule and the valuable experimental products in the capsule.

The two were carried on a stretcher. After briefly greeting everyone, they were sent to the Institute of Aerospace Medicine for physical examination.

——

At the same time that the astronauts returned to Earth, a material that was not too eye-catching was born in the Materials Experiment Center of the Rocket Research Institute.

High-purity gallium nitride and diodes made from it.

This material is still a laboratory product today.

Major laboratories around the world produce a lot of output every year.

Especially since entering the 21st century, everyone has become increasingly aware that the development of third-generation semiconductors must be based on gallium nitride, silicon carbide, zinc oxide, etc.

However, the technology is not yet mature at this time. Although everyone already has this understanding, it is generally believed that there is still at least fifteen years between this and practical application.

In fact, if it weren't for Zhang Xingyang's vigorous promotion.

Gallium nitride products, which have great prospects in both the military and civilian markets, may not develop until more than ten years later.

In later generations, gallium nitride was widely used in phased array radars.

Our country has the world's largest production of gallium nitride, with an annual output of nearly 600 tons, which is close to 90% of the world's production capacity!

This was also one of the important factors why at that time, even agricultural drones were able to use phased array radar in China.

Without him, I can only measure myself!

This is why, after the country introduced export restrictions on gallium nitride, everyone believed that it would have a major impact on the foreign radar industry.

Back to the present, the gallium nitride produced by Zhang Xingyang and others is extremely pure and will become an excellent raw material for radar products.

However, Zhang Xingyang paid more attention to another point.

Gallium nitride itself has considerable physical performance advantages compared to currently commonly used silicon semiconductors.

For example, large bandgap width, high breakdown electric field, high saturation electron drift velocity, high thermal conductivity, high radiation resistance, etc.

In the future, it will be widely used in various inverters, DC/DC converters, etc.

In particular, the gallium nitride diode that Zhang Xingyang and the others have just developed is the leader among converters.

After Zhang Xingyang completed the research and development of gallium nitride diodes, he completed the research and development of DC-RF and RF-DC converters at an extremely fast speed.

DC-RF, that is, current-microwave conversion.

The current is converted into microwaves through the microwave generating unit.

RF-DC, on the other hand, converts microwaves into electric current.

This thing may seem inconspicuous, but it will involve changes in the future energy industry.

Microwave power transmission!

Or to use Zhang Xingyang’s more familiar name, “Space Three Gorges”!

The concept of microwave power transmission is actually not new. Some people have proposed this as early as when people discovered the characteristics of microwaves.

Microwave power transmission also has many advantages.

First of all, compared with traditional wire transmission, its loss rate is relatively low, and there is almost no loss in space.

Even in the atmosphere, there is only less than 5% loss.

Secondly, it is not restricted by terrain, and the relationship between power stations and power users can ignore terrain factors.

Even if this cannot be applied on a large scale, it is of great use in emergency rescue, post-disaster relief, etc.

Previously, there were two main technical problems in interception.

One is the problem of efficiency and power in converting electric current into microwaves. Before this, due to the limitations of the semiconductor industry, efficiency and power were relatively low.

It is difficult to meet the demand for high-power conversion, and the conversion efficiency is relatively low, and a lot of energy is consumed in the conversion process.

The physical properties of gallium nitride can solve this problem very well. Not only can it withstand greater power, but the conversion efficiency has also been greatly improved.

Zhang Xingyang placed DC-RF converters and RF-DC converters in the experimental field about fifteen meters wide.

One end is a generator and the other is an electric motor.

It is used to verify the working efficiency of this system and whether it can meet the requirements.

"Xingyang, can this really succeed?"

Even though Zhang Xingyang had repeatedly created technological miracles before, Geng Bo still maintained a skeptical attitude.

Because this seems to be a bit beyond everyone's imagination. Before this, the so-called wireless power transmission on the market was actually mostly the application of electromagnetic induction.

This is how most mobile phones will be charged wirelessly in later generations.

Although this kind of wireless power transmission gets rid of the shackles of wires, it is not very useful because the wireless distance is too small and it can only be effective when it is close to each other.

There are not many application scenarios in daily life, let alone in industrial production.

Microwave power transmission can really get rid of this limitation!

Although the equipment looks not small now, in industrial production, it is already considered very small.

"The success of the experiment is certain. The main question is how high the conversion efficiency can be."

Zhang Xingyang started the generator at one end and answered Geng Bo's question.

The DC-RF converter quickly converted the electrical energy into microwaves, and then transmitted it to the RF-DC converter fifteen meters away through a specific frequency.

The microwaves are converted into electric current, which drives the operation of the motor.

The power of the motor was quickly displayed on the display, combined with the generator on the other side.

It is easy for everyone to obtain the efficiency of microwave power transmission.

Thirty-two percent!

This efficiency can be said to be far beyond everyone’s imagination.

This energy utilization rate can be said to be very high.

Zhang Xingyang looked at the data on the display and smiled:

"We can solve big energy problems in the future!"

Everyone present had worked in the aerospace system for a long time, so of course they knew what he meant.

This is an idea that was put forward in the last century.

Build large-scale solar power stations in space, and while generating electricity, transmit this energy to the ground through microwaves.

Cities with huge ground power consumption can relieve a lot of pressure.

Especially in the summer when power demand is strong, it can solve the problem of power shortage in many mega cities with tens of millions of dollars.

Of course, the benefits of microwave power transmission don’t stop there.

With microwave power transmission, drones equipped with RF-DC converters can cruise in the sky almost 24 hours a day.

There is no need to stop the charging process anymore, and the internal vulnerable parts need to be replaced within just a few days.

It was only after this that the UAV swarm tactics ushered in a real opportunity for development! (End of chapter)