It is really not necessary to make the Yongdao into a floor door, after all, the first two doors have been broken through, and the significance of making the Yongdao into a hidden door is not great.

In addition, it seems that it will become inconvenient to carry materials by making the door into a floor door and changing the structure of the corridor.

Since I don't plan to move anywhere else, the drawings for this gate are ready.

Looking at the CAD design drawings made on the computer, Chen Xin couldn't help but sigh with emotion, this is still a skill he taught himself when he was looking for his first job when he just graduated from college, and he has not drawn drawings for a long time after so many years.

Originally, Chen Xin thought that after the end came, he would not draw drawings anymore, but he didn't expect to use this skill again so soon.

But the reality is always more bizarre and complicated than we imagined, and maybe fate will give you an unexpected surprise at some point.

Chen Xin couldn't tell whether this was a surprise or a fright, so he closed the laptop again, put it on the bedside, checked the pistol in the bedside table and put it in the place where he could reach it most easily, Chen Xin turned off the bedroom light, covered the quilt and closed his eyes.

Tomorrow, he will upgrade the gate and make an oxygen concentrator for Mo Qingyan, and there are still a lot of things.

However, this feeling of fulfillment is not bad for Chen Xin.

When Chen Xin fell asleep, there was still a faint green light in the bedroom, which was the algae oxygen concentrator in the corner working.

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Chen Xin, who woke up early, was already sitting in front of the workbench, and he planned to make the oxygen concentrator for Mo Qingyan first.

The materials sent by Ding Ning are sufficient, and it is enough to make an oxygen concentrator, the only trouble is that although the glass she brought is guaranteed to be a whole piece as much as possible, there are still a lot of broken glass that need to be cut and spliced.

In fact, the best use of these broken glasses is if there is a furnace to melt the glass and then remake it into the desired shape, rather than gluing it together.

However, for Chen Xin, he only needs to have glass as a raw material, and with the help of the system, he can easily process these glasses into any shape he wants.

At this time, next to the workbench, the original broken glass has been reshaped into a tall annular straight tube, and Chen Xin is making the base.

The base of this microalgae oxygen generator is the key, and the glass straight tube is relatively just a container, and it doesn't matter what shape it is made, but the annular straight tube is relatively the most efficient in the use of light.

Pipes and vacuum pumps are installed on the base to fill the circular tube with carbon dioxide to stimulate photosynthesis by microalgae.

Therefore, the chassis should be laid with an annular pipe, and carbon dioxide should be pumped into the pipe with an air pump, so that the carbon dioxide can enter the annular straight cylinder from the small hole in the pipe.

However, the production of high-purity carbon dioxide is more troublesome and dangerous, so Chen Xin directly uses ordinary air here, allowing the chassis to directly absorb the surrounding air.

As for the fill light, it is installed on the top cover, because the ring is placed vertically, and the dead algae will deposit to the bottom, which will be relatively less transmittal.

With the various tools on the workbench and the upgraded oxygen concentrator in the bedroom as a reference, Mo Qingyan's oxygen concentrator is very fast to make.

After all, the structure itself is very simple, the technology is relatively uncomplicated, and with the assistance of the system, Chen Xin quickly made everything and then assembled it together.

Compared with the oxygen concentrator in the bedroom with an upgraded system, the one that Chen Xin made by himself looked rougher, and there was no big difference in other than that, and it was enough for Mo Qingyan to use.

Therefore, after the oxygen concentrator was completed, Chen Xin did not spend survival points to upgrade this oxygen concentrator, and planned to hand it over to Mo Qingyan like this.

Putting the prepared oxygen concentrator aside, Chen Xin looked at the time, planning to have lunch first, take a rest, and come to upgrade the gate in the afternoon.

Although it was just to confirm the upgrade, Chen Xin didn't plan to finish it in a hurry.

There wasn't much to do in the shelter every day now, and Chen Xin didn't want to do everything at once and then become idle to play games.

Of course, Chen Xin is not really nothing, and the daily maintenance of the planting greenhouse cannot be saved.

It's just that as the crops enter the growing season, he only needs to ensure water supply and light, and keep the greenhouse running.

As for the control of various pests and diseases common in general greenhouses or planting greenhouses, Chen Xin is naturally also very concerned.

However, I don't know if the seeds bought are good, or the system has been upgraded to plant greenhouses with black technology, at least so far, Chen Xin has not encountered any crop pests and diseases, and all crops are growing very healthy.

The upland rice he planted has now entered the long panicle stage, starting from the young panicle to the heading development, this process will last about 30 days, according to the growth cycle, in a few days these upland rice should enter the fruiting stage, and begin to tassel.

I have to say that Chen Xin really had never planted before, and after he really started planting upland rice, he realized that the so-called upland rice is planted twice a year, just because the environment and climate do not allow it.

If it is in a planting greenhouse, let alone two seasons a year, he can plant three seasons a year.

In this way, Chen Xin found that after he expanded the planting greenhouse to the current 200 square meters, if he used half of the land to grow upland rice, he could harvest about 600 catties of rice a year, although it was not a lot, but it was enough to eat it as a staple food to maintain Chen Xin's consumption alone.

Even if Chen Xin upgrades the planting greenhouse and upgrades the current single-layer hydroponic planting to multi-layer hydroponic planting, all of which are used to grow vegetables, and the land is used to grow upland rice, his output can even afford one or two more people.

As for further upgrading, creating a symbiotic aquaponics cycle system and animal breeding, and simply raising some fish or chickens, rabbits and other birds, it will be able to maintain the survival needs of more people.

And the main thing is that Chen Xin can now exchange vegetables for food from the SWAT team.

Although the food in the shelter that Qin Lan brought before really didn't dare to compliment it in terms of taste or texture, at least it was food, something that could be eaten, and it was still a relatively good food now.

When it comes to food, after Chen Xin thought about it, he decided to eat the mushroom roast rat meat that Qin Lan brought at noon today, as for the canned meat that he exchanged from Mo Qingyan before, he could keep it and eat it slowly.

After all, rat meat is now eaten, but pork is not sure when it will be eaten again.