Kai Fu Han

Chapter 152
In later generations, physics is generally taught from the second grade of junior high school, and chemistry is generally taught from the third grade of junior high school.The reason for setting up subjects in this way is because the first year of junior high school is just the first year of elementary school, and the first-year students who have just entered junior middle school are still affected by the learning ideas and habits of elementary school. Therefore, it is not suitable to teach more theoretical subjects such as physics and chemistry in the first year of junior high school. Strong subjects.And learning physical chemistry requires junior high school mathematics knowledge as a foundation, because many of the operations are based on some mathematical operations.

According to Liu Xinqi's plan, in the future, the primary school will be set up for five years, and the middle school will be set for five years.

The initial planned compulsory education was only five years of primary school.

School children start school when they are seven years old and study for five years until they are 12 years old. If they have good grades, they continue to study in middle school.If your grades are not good, you can enter a technical school to learn skills for four years, and then you can start working.

After five years of middle school, if you study well, you can continue to study in a martial arts hall, a university hall or a normal school.If you can't keep up with your studies, you can start working directly, or you can start working after learning skills for another three years.

Liu Xinqi read a physics book for the second grade of middle school. It contained the most basic physics knowledge and was very clear and suitable for beginners.

After flipping through a few pages, he put down the book in his hand and looked at Gao Hui's desk again.

There is a pile of straw paper in the middle of the table, with some mathematical knowledge on it.

Gao Hui saw Liu Xinqi looking at the part he was working on and introduced:
"This is mathematics for the third grade of elementary school. I divided the mathematics knowledge you gave me into ten school years and twenty volumes. The elementary school ones are very, very simple."

"It's better to keep things simple. Children in primary schools are immature and can't learn difficult subjects. And in the future, there will be other courses in primary schools, one of which is mathematics."

Liu Xinqi said:
"The teaching materials are ready. No matter where I am, send me a copy. Even if I am at sea, I will ask the trading ship to send me a copy."

"Ok."

This time going south and east, Zhao Liang and Liu Xinqi mainly opened up trade routes. In addition to the eight cargo ships following the fleet, there will also be regular trade fleets in the future, making the income of Xinghan League's sea trade sustainable. .

After seeing Gao Hui, Liu Xinqi stayed in the office and helped Gao Hui answer some questions he had in his recent studies, and then taught him some advanced mathematics knowledge.

Time passed quickly, and they only taught him a few superficial things. When Gao Hui was very interested, the sky had already darkened. Liu Xinqi refused Gao Hui's offer to stay and returned home to chat with his mother about daily life.

……

July [-]th.

Liu Xinqi got up early, went out in the dark, and walked toward the port.

There was an oil lamp hanging on the mast of the Qizhou ship left in the port. Although the light was dim, it pointed out the direction for Liu Xinqi.

On board the ship, Liu Xinqi saw Li Cang directing the crew to prepare for setting sail.

"Has the entourage arrived?"

Liu Xinqi walked to Li Cang.

"There are still two translators and three guides who have not arrived. You have arranged for the crew to go to the registered address before boarding the ship."

Li Cang replied.

Liu Xinqi didn't ask any more questions and walked towards the cabin.

There are not many trade goods on board the Qizhou, but they are of high value and are all glass products.When I came to the cabin on the ground floor, I saw that it was filled with various glass products wrapped in thick straw mats.

Boating on the sea can be very bumpy, and these straw mats are shock-proof measures to prevent the glass from shattering.

He untied a small straw bag and took out a glass inside. The shape of this cup is basically the same as that of later generations. The green color on the glass is very light and cannot be seen without looking carefully.But Liu Xinqi knew that if he looked at the sun, the green color would be obvious.

Although this batch of glass products still has some light green color, it is still considered a luxury product in this era.Because others have never seen pure white and transparent colored glaze or glass, they do not know that this light green color is caused by impurities that have not been removed.

Put the glass back into the straw bag and tie the rope.

I changed to another cabin to check again. This cabin was filled with glass mirrors.

Seeing these mirrors, Liu Xinqi couldn't help but recall the difficulty of making mirror coatings before.

A simple glass plate cannot be regarded as a mirror. It must be coated with a base plate that reflects light before it can be called a mirror.

At first, Liu Xinqi guided Liu Xinshi to stick a layer of tinfoil on the back of the glass, but many attempts were not very satisfactory. If glue is not used between the tinfoil and the glass, and only a wooden frame is used to fix the two together, the tinfoil is too thin. , it will wrinkle or crack very easily.

If you use glue, it will affect the reflection of light and the mirror will be very ugly.

Finally, Liu Xinqi remembered some posts he had read before, which said that the coating behind the mirror initially contained mercury.

Then I tried to stick a layer of tin foil tightly on the glass, and then poured mercury on the tin foil. I later found that the tin was dissolved by the mercury into a viscous silver-white liquid, which would stick firmly to the mirror and become a very sticky liquid. A perfect mirror.

Liu Xinshi was very excited when he first saw this mirror. This mirror reflected every detail of a person, which was much better than a bronze mirror.

However, Liu Xinqi has always been worried about the use of mercury for the reflective coating. After all, Liu Xinqi, who came from a later generation, knew that mercury, also known as mercury, is highly toxic and volatile.

If tin amalgam is really used as a coating, it will definitely cause huge harm to the health of people who use this kind of mirror.

After thinking for a long time, Liu Xinqi finally gave up using tin amalgam as a coating to produce mirrors.

After soliciting opinions and suggestions from many parties, Liu Xinqi learned about the technology of gilding, which the ancients had mastered in BC.

First, gold is dissolved in mercury to make a paste-like gold amalgam. The gold amalgam is evenly applied to the clean glass surface. The mercury is volatilized by heating, and the gold solidifies with the glass surface to form a bright golden coating.

In addition to the yellowish color of the reflected portrait, the mirror made by this method still has very high clarity and looks very precious.Moreover, the portrait reflected in the bronze mirror is also yellow, so it is not difficult for this kind of mirror to be accepted.

Originally planning to stick to the high cost of producing this kind of yellow mirror, Liu Xinqi had an idea: "Since it can be gilded, can it be gilded with silver?"

After trying it, it worked, and the problem of coating the glass with a reflective layer was finally solved.

This silver plating method is what Liu Xinqi can think of and is the most suitable silver plating method for the current technical environment.

There are basically no defects in other aspects except that the production personnel's exposure to Yingong solution will harm their bodies.

(End of this chapter)