The two men spent less than 10 minutes in the jewelry store before they fled. Picking jewelry also requires some skills, and Qin Hai and Ning Jing undoubtedly lack such skills.

According to Qin Hai's original idea, it was just a diamond ring, and it was a big deal to only buy expensive ones, not the right ones, as long as they could win a smile from the beauties, what was it to spend some money for the wealthy Chairman Qin?

It's a pity that practice and theory are too far apart, and when more than a dozen diamond rings of different grades are placed in front of the two of them together, Qin Hai deeply understands what it means to be picky. Under the backdrop of high-end diamond rings, those low-grade goods obviously make people feel unsightly. However, when they set their sights on diamond rings with titles such as "Queen of India" and "Eye of Africa", they found that the price of these diamond rings was suffocating.

Qin Hai was ready to give a little "blood", but in the face of the high price of millions of dollars, he still couldn't convince himself to make a move. The annual salary of an ordinary worker in China is only more than 1,000 yuan, and a diamond ring is equivalent to 1,000 years of wages for a worker.

As for Tranquility, when she saw the price of the diamond ring, her face turned pale with fright, and she dared to accept the clerk's invitation to try it on. In the end, the two of them could only look embarrassed and find an excuse to slip away.

"Giggles...... ran out of the jewelry store dozens of meters away, and after making sure that there was no clerk watching them outside the door, Ning Jing slowed down, took Qin Hai's arm, and smiled backwards.

"What are you laughing at?" Qin Hai was a little wolf, as a rich and handsome man who vowed to buy a diamond ring and propose, he was frightened by the price of the jewelry and escaped. It's really a shameless thing.

"Qin Hai, you said that you are also a big boss with a net worth of tens of billions, how can you not buy a diamond ring of 1 million US dollars?" Jing Jing said teasingly, she seemed to have forgotten that when she escaped from the jewelry store just now, she ran faster than Qin Hai, for fear that it would cost her to take one more look.

"That's too much of a price, isn't it? I didn't see the difference between that diamond called 'Princess Rose' and the other diamonds. It's just that the color is a little more transparent than other diamonds, why is the price more than ten times more expensive? Qin Hai muttered and said, "Even if I have money, it doesn't mean that I should be the wrongdoer." ”

Tranquility retorted: "What is the big wrong, people are jewelers for hundreds of years, can they still understand the price of jewelry?" Do you understand the truth that you get what you pay for? Don't you think that 'Princess Rose' is more beautiful than other diamonds? You can see it by comparison. ”

"You don't really like it, do you?" Qin Hai said seriously, "If you really like it, then let's go back and buy it now, you're right." $1 million is not much. ”

"Don't, don't, I'm joking." Tranquility hastened to deny it. At heart, of course she loves beautiful diamonds, but it would be more than she could afford to spend $1 million on a diamond. In any case, she was also a child who grew up in an ordinary working family, and she was educated frugally since she was a child. Even if her family is rich now, her boyfriend Qin Hai is even more of a billionaire. She also didn't get into the habit of spending too much.

"If I spend 1 million to buy you a diamond ring, don't talk about anyone else. Lao Ning will train me to death. Qin Hai made excuses for his stinginess. But this excuse is indeed true, if he buys this diamond ring, Ning Zhongying will definitely be furious, and he and Ning Ning will be scolded by Ning Zhongying at that time. With his understanding of Ning Zhongying, he knew that this was definitely not alarmist.

"Okay, you Qin Hai, do you dare to call my father Lao Ning now?" Serenity warned with a glare.

"That's not what I called first. Is it your brother fat man who calls it that way in private? Qin Hai decisively sold Ning Mo.

Ning Ning smiled: "Speaking of my brother, I remembered, when you accompanied my brother to buy a diamond ring, how did you buy it?" I didn't hear you escaped that time. ”

"That's in Pujiang." Qin Hai explained, "We went to the best jewelry stores. As soon as I went, I asked the clerk to take out the best diamond ring, and then the fat man looked at it and said that it was very good-looking and the price was not expensive, and then he bought it. The best diamond ring in the store, that is, more than 170,000 yuan, is only more than 30,000 US dollars. That's what I was going to do, but who knew that diamond rings in Paris were so expensive. ”

"That store also has a diamond ring of more than 30,000 dollars just now, why don't you buy it?" Tranquility raises the bar.

Qin Hai shook his head: "Here, more than 30,000 US dollars is the second-class, if I pick the second-class one to buy, won't I leave a handle behind?" ”

"Are you still afraid of falling behind?" Serenity smiled. In her heart, she actually felt a little uncomfortable buying the cheapest diamond ring in a store, after all, a diamond ring is a special ornament, and it can't be left behind.

"Actually, it's not a matter of falling into the handle, but I don't think this thing is worth so much money." Qin Haidao, "In the eyes of a materials expert, isn't the so-called diamond an allotrope of graphite?" $1 million, how much graphite can you buy, why don't we make a graphite ring ourselves? ”

The so-called allotropic form is a substance composed of the same element with different physical properties. Diamond and graphite have exactly the same chemical composition and are both made of carbon. It's just that because of the different ways in which the carbon atoms are arranged, one becomes the diamond that is the king of hardness, and the other is the soft graphite. Qin Hai said that diamond and graphite are the same thing, which can be regarded as a kind of material scientist's little cleverness.

Tranquility laughed angrily at Qin Hai's brain, she pointed at Qin Hai and said, "You can figure it out, do you still plan to cut graphite into thin slices and make a ring of rings?" People who know say I'm wearing an allotropic form of a diamond, but people who don't know think I'm wearing a thimble. ”

Qin Hai's purpose of talking nonsense was just to hide his previous embarrassment, and seeing that Ningning's attention had been successfully diverted, he also breathed a sigh of relief and said, "Actually, it's not impossible to cut graphite into thin slices, if you cut it thin enough......"

At this, he suddenly stopped, staring at Tranquility in a daze, his eyes widening.

"What's wrong? Is there anything on my face? Tranquility was stunned by Qin Hai's actions, and subconsciously reached out to wipe his face, but he couldn't see anything dirty on his hands.

"It's not the face, I mean...... How did you come up with the idea of slicing graphite into thin slices? Qin Hai asked in a daze.

"Is there anything wrong with slicing graphite?" Tranquility said strangely, "If you want to make a ring, don't you need a thin sheet?" …… Qin Hai, you don't really want to make a graphite ring, do you? ”

"Why not?" A strange smile appeared on Qin Hai's face, "If I can cut graphite very thinly, so thin that it is only one atom thick, the ring made must be very beautiful and very strong." ”

"Qin Hai, are you okay?" Tranquility didn't know what to do, reached out and pushed Qin Hai, and said, "How can it be possible to cut out graphite that is only one atom thick, you can't be talking about carbon nanotubes, right?" ”

The so-called carbon nanotube refers to a slender tubular material made of single or multi-layer graphite sheets, with an inner diameter of less than 3 nanometers and a length of about 1 micron. This material was discovered by Japanese scholars in 1991 when they used high-resolution electron microscopy to observe the graphite electrode products of arc vacuum evaporation, and then many scholars invented several preparation methods, making it an important new nanomaterial.

With the different diameters and helix angles, carbon nanotubes can show the characteristics of conductive, semi-conductive and insulating, respectively, and can be used to fabricate electronic components at the molecular level. It also has high strength and elasticity, while being very lightweight, so it has the potential to be used to make lightweight, high-strength fibers. Science fiction writers have envisioned an elevator between the Earth and the Moon to facilitate commuting, and it has been pointed out that the ideal material for such an elevator would be carbon nanotube fibers.

Another very interesting fact about carbon nanotubes is that they have a very strong light-absorbing capacity, and some scientists have used nano-carbon tubes to create materials that are said to be able to absorb light completely. That is, the light shines on this material without the slightest reflection, so it can be called the darkest material in the world.

Tranquility is doing superconductivity research, and she has also cared about the new material of carbon nanotubes, but she can't think of why Qin Hai would think of such a material inexplicably, is it because she said "cut graphite into thin slices"?

Qin Hai gave a negative answer to Tranquility's speculation: "NoNoNo, not a carbon nanotube, but a two-dimensional material, is a thin film formed by carbon atoms connected to each other, so thin that it is only as thick as one carbon atom. Think about it, what kind of properties such a thin material will have. ”

"A thin film material as thick as 1 atom?" Tranquility frowned and thought for a while, and said, "I can't imagine such a material, if it is only as thick as 1 atom, will this material be very fragile?" I doubt it can survive in reality. ”

"A carbon nanotube is one atom thick, but it's just rolled into a tube. If you cut and flatten the carbon nanotube, isn't it just a thin slice with the thickness of one atom? What do you think of the strength of carbon nanotubes? ”

Qin Hai smiled and revealed Tranquility, in fact, he didn't need Tranquility to give any answer, because he was very familiar with the properties of the material he had described. This material is a new type of material that has been stirring up in the field of materials science and even in the economic field in the first ten years of the 21st century:

Graphene! (To be continued......)

PS: Graphene is on the scene. You know, the cover of this book is a diagram of the atomic structure of graphene, which is a very amazing material?