The military-industrial scientific research system of the academic master.

After Li Nianheng's question, the entire conference room finally returned to the relatively serious atmosphere at the beginning.

Lu Jinhui then switched to another PPT.

"We also divided the samples from the Badain Jaran Desert into three groups, A, B, and C, according to the distribution of sampling points. The characteristics of the three groups of samples are consistent. Among them, group B, which is the southern part of the desert close to the northern foot of the Qilian Mountains and Ayou Banner, has the most obvious characteristics, so it will be used as an example in the following explanation..."

"Relatively speaking, the situation of Badain Jaran Group B is different from that of Tengger Group A. Its chemical properties, as well as hydraulic characteristics such as bulk density, water holding capacity, saturated hydraulic conductivity, and porosity are similar to those of ordinary deserts, but its particle situation is quite different from that of typical desert sands."

He said, and released two more photos similar to the previous ones.

It’s just that the objects of comparison this time are slightly different.

It can be seen that the gravel samples in group B on the left are very different in appearance.

At least it doesn't look so round anymore.

However, due to its inappropriate chemical properties and porosity, it cannot replace the role of river sand.

"Through the same effective stress test as before, we found that the normal contact pressure and tangential constraint force of the Badain Jaran Group B were significantly better than those of other samples including the Tengger Group A, and even better than some river sands when there was obvious constraint on the side of the sand column..."

"..."

The introduction ended quickly.

This time, the response from the crowd seemed much colder.

The main thing is... I really can't think of the meaning of this feature for the moment.

After all, the uses of sand are relatively narrow.

After excluding building materials, which is the direction most likely to produce results, it seems that only the semiconductor industry is left...

In theory, it can be used to extract silicon.

However, semiconductor-grade sand raw materials need to be relatively pure in composition and have good looseness.

However, a lot of magnesium, manganese and calcium components can be detected in the composition of Badain Jaran Group B, especially the latter two, which are harmful components for the silicon industry. In addition, the sand is relatively compact and not conducive to subsequent processing steps.

All in all, it looks a bit tasteless.

However, Li Nianheng was still quite excited.

Because of such distinctive geological conditions - whether meaningful or not - they are very suitable for calibrating SAR signals.

"Professor Chang, Professor Meng, do you think we can start to summarize the patterns in this data after we return?"

Meng Zhenyuan, who had been listening, nodded:

"At least, we can now clearly see that the results obtained after data dimensionality reduction processing can indeed correspond one by one to geological conditions with different characteristics..."

Although Chang Haonan was the one who specifically designed the data extraction and processing algorithm, the starting point of everything, that is, the remote sensing data analysis project, was still under Meng Zhenyuan's name.

Even according to the most stringent conditions, the project can be considered a complete success at this point.

"Then Professor Chang, what you mean is..."

Li Nianheng didn't hear Chang Haonan's response, so he turned to look at him.

But he found that Chang Haonan was holding his chin with one hand, with his head down in deep thought, and he never spoke.

There was a brief silence.

"Then...if all comrades have no other questions, I will introduce the preliminary situation of the two desert areas here. Next should be the three areas in the northern foothills of the Tianshan Mountains. Please..."

As Zhai Mingguo, who was temporarily acting as the host, spoke, Lu Jinhui, who was already very satisfied with his presentation, began to pack up his things and prepare to give the podium to the next person.

However, at this moment, Chang Haonan suddenly raised his head again:

"and many more!"

Lu Jinhui paused for a moment in putting away the computer, then plugged back the signal cable that had been unplugged.

The projector came back on.

"Professor Chang, please go ahead."

"In addition to the normal contact pressure and tangential constraint force, have you measured the constraint tension and constraint moment of this set of samples?"

Chang Haonan pointed at the curtain.

"Constraint tension and restraint moment..."

This somewhat awkward question made Lu Jinhui stunned, and then he shook his head in confusion:

"No……"

In fact, stress testing itself is not even part of the standard testing process.

The normal contact pressure and tangential constraint force that had already been made were filled in by him referring to the papers on geotechnical engineering.

Looking at Lu Jinhui's puzzled look on the stage, Chang Haonan organized his words and explained:

"If this set of desert sand samples can provide normal contact pressure and tangential constraint force at the same time under certain conditions..."

At this point, he felt that words alone might not be enough to describe it, so he looked at Zhai Mingguo next to him:

"Researcher Zhai, do we have a blackboard here?"

The latter looked around and found that there was indeed only the piece on the wall in the conference room.

But it was blocked by the curtain.

However, after all, it was Chang Haonan's request, so it must be met.

A few minutes later, two staff members came in from outside the door pushing a small blackboard on wheels.

Chang Haonan didn't hesitate and stood up and walked to the podium.

This action made Lu Jinhui a little confused about his position for a moment.

"Oh...you go down first."

Chang Haonan said.

Then he turned around, picked up the chalk and quickly drew dozens of small balls on the blackboard, while explaining:

"Comrades, look here."

"Assuming that the sand particles have normal contact pressure, tangential constraint force, constraint tension and constraint moment at the same time, and can also guarantee a certain degree of follow-up freedom, it means that each particle can generate both constraint reaction force and displacement along the direction of constraint reaction force."

"And if we expand the perspective and make the sand particles in the entire space have this characteristic, and make them in a rheological state in some way, then any particle can contact another particle in any direction to generate constraints. Even if the two particles separate, as long as they can restore contact, this constraint can be reshaped..."

As he analyzed, the blackboard was gradually filled with white, yellow, and blue chalk marks, and even the small balls that were originally drawn on it were difficult to see clearly.

In fact, this kind of analysis should be carried out on a computer in a form similar to molecular dynamics simulation.

It’s just that Chang Haonan was just brainstorming, so for now he can only present it on the blackboard.

Fortunately, there were still people below who understood what he meant.

"That is to say, if we can somehow transform the sand... uh... this type of sand from a discrete state to a rheological state, then the sand particles that were originally separated one by one will be transformed into a body with omnidirectional constraints and can self-repair to a certain extent..."

Zhai Mingguo had obviously grasped the key points of what Chang Haonan had just introduced.

But there is really no way to express it more vividly.

At this time, Lv Jinhui, who had just returned to his seat, added a sentence at the right time:

"The properties will be similar to... No, it will be basically equivalent to soil?"

As soon as these words were spoken, everyone in the conference room understood instantly.

Although the soil transformed from sand is still different from real soil in chemical composition, its physical properties have already acquired the ability to store water, nutrients and air.

This is enough.

As long as the eco-mechanical properties can be maintained over the long term, what is missing can be made up by artificial means such as precipitation or fertilization.

If you look at the long term...

It can even be said that deserts with sand body characteristics close to those of Badain Jaran Group B have the opportunity to be transformed into soil that meets the conditions for large-scale production!

For China, which is facing serious land degradation and sandstorm problems, this is like a blessing in disguise.

Especially in the central and western parts of Inner Mongolia and the central part of Longyuan, the terrain is actually slopes and plains that are easy to cultivate on a large scale, but the demand cannot be met because the land conditions are too poor.

If we can really transform these parts into arable land...

Everyone looked at each other.

OK.

I dare not even think about it.