Liu Yuehong blushed, Zhao Weihua hurriedly took Liu Yuehong home when she saw this, everyone laughed, Zhao Weihua, this kid, can be said to be grown up by them, tall, handsome, and smart, especially popular with little girls in the family home, and they also like it.

"Mom and Dad, this is Liu Yuehong, this is my object!" Zhao Weihua's face was full of smiles, "Yuehong, this is my parents!"

"Hello, uncle, aunt!"

Liu Yuehong is still a little shy, Zhao's mother likes Liu Yuehong when she sees her, this girl is beautiful, and she is a good fortune at first glance, holding Liu Yuehong's hand and not letting go.

"Good girl, don't be polite when you come to our house, it will be your own home in the future!"

"Yes!"

Liu Yuehong blushed and nodded, Zhao Weihua hurriedly took the things in his hand, "Mom and Dad, this is what Yuehong bought for you, you keep this malt milk essence for yourself, and this packet of brown sugar, you also keep it, this meat will be eaten today, this is also a little bit of Yuehong's heart!"

"Look at you, you're here, what kind of gifts do you bring, this kid is too polite!"

"Auntie, this is all as it should be, but I don't know what you and your uncle like, so I just bought some casually, don't dislike it!"

"Nonsense, you and Wei Hua are good, Auntie is happier than anything else, but she won't dislike it!"

Zhao's father also looked happy, at noon, Liu Yuehong helped Zhao's mother to cook together, Zhao's mother's attitude towards Liu Yuehong was even more like, it can be seen that this future second daughter-in-law will be a good wife and mother in the future, and Wei Hua's kid will be blessed in the future.

......

The Zhao family is still very harmonious, Zhao Weihua's eldest brother and sister-in-law are also easier people to get along with, and Zhao's mother also said that after they get married, they will be separated and not live with the elderly, Liu Yuehong is still happier about this, after all, the relationship between mother-in-law and daughter-in-law has been a contradiction since ancient times, she can see that Zhao's mother really likes herself, but there will be contradictions when living together, as the so-called far fragrance and near smell, it will be better not to live together!

Liu Yuehong met the Zhao family's parents, and the next day Zhao Weihua proposed that he wanted to go to Dashantun to visit his future father-in-law, after all, he really wanted to live with his future little wife, and now his life alone is simply too fucked.

Liu Yuehong went well, Liu Qianqian and her party also returned to the five counties from Harbin City, as for the results of the provincial competition, it will be announced at the beginning of the year, at this time the school is already preparing for the final exam, for Liu Qianqian these are not things, after the exam, Liu Qianqian will plunge into the Institute of Physics, research her own sonic weapons.

Liu Qianqian asked people to take the words back, and took root in the Institute of Physics, because there were many materials she wanted, she had to start researching materials, because it was to make a self-defense weapon for herself, Liu Qianqian naturally would not compromise, and she would only be happier about it, because Liu Qianqian easily researched something, cutting-edge technology, they can only sigh that Liu Qianqian's head is really the strongest brain, and it may contain technology that has surpassed this world for decades, and in this regard, the top has also paid more attention to Liu Qianqian's safety.

"Sissi, go eat first, and pay attention to your body when doing experiments, you can't burn your body, let's eat first!"

"You're still young, and the most important thing is to pay attention to your body, you're still young, don't be so anxious. ”

Professor Wang looked at Liu Qianqian who was doing experiments in the laboratory, Liu Qianqian has been in the laboratory for the past few days, and even her meals are solved in the laboratory, I have to say that Liu Qianqian has simply subverted their impression of her, so that she can be regarded as a researcher engaged in scientific research.

......

When a person is in an environment where the volume above 120 decibels is present without any protection, the hearing system will be uncomfortable or damaged, and when the volume rises above 150 decibels, the person in this environment will have eardrum rupture and bleeding, loss of hearing, and even mental disorders.

Infrasound waves are not easy to attenuate and are not easily absorbed by water and air, and the wavelength of infrasound waves is often very long, so it can be diffracted around obstacles like electromagnetic waves, and the killing range is large, but it is difficult to control the direction.

The high-power infrasound waves can cause strong resonance in the internal organs, causing nausea, headaches, difficulty breathing, and even causing blood vessels to rupture and damage to internal organs.

The effect of high-power ultrasonic waves is similar to that of infrasound waves, but the transmission direction is better than that of infrasound waves, almost propagating in a straight line, easy to control, and the straight line penetration ability is strong, but the killing range is small.

Conventional sonic weapons do not use sound waves in the human audible frequency range because infrasonic waves and ultrasound waves are highly concealed.

Liu Qianqian is studying infrasonic weapons this time, for her, the lethality of infrasonic weapons is the greatest, and in her previous life, infrasonic weapons have been able to control the direction, and they can also accurately control to a certain point and a certain range, such an infrasonic weapon is what she needs.

Infrasonic weapons are high-power weapons capable of emitting infrasonic waves of up to 20 hertz. Complex sound waves are mechanical longitudinal waves, which can travel in solids, liquids, and gases. The sound that people can hear on a daily basis is a sound wave in the frequency range of 20~20000Hz.

Below 20Hz is infrasound. The reason why infrasound waves are used as military weapons is that infrasound waves and human organs have similar natural frequencies, so they will resonate. The resonance of infrasound waves with human organs will cause the organs to deform, displace and even rupture, so as to achieve the purpose of killing.

Infrasonic weapons can be broadly divided into two categories: neurological infrasound weapons and organ-type infrasound weapons.

The infrasound frequency of "neurological" infrasound weapons is very close to the alpha rhythm of the human brain (8~12Hz), so when the infrasound wave acts on the human body, it will stimulate the human brain, cause resonance, and have a certain impact on people's psychology and consciousness: the light person feels uncomfortable, the concentration decreases, and the mood is restless, resulting in dizziness and nausea; in the severe case, it makes people nervous, crazy, shock, fainting, and losing the ability to think.

The infrasound frequency of the "organ-type" infrasound weapon is similar to the natural frequency of the human internal organs (4~18Hz), which will cause a strong resonance of the human internal organs. Mild cases include muscle spasms, trembling all over the body, and difficulty breathing, while severe cases have ruptured blood vessels, internal organs are damaged, and even rapid death.

Liu Qianqian put down the test in her hand and saw Professor Wang as soon as she looked up.

"Sissi, let's go eat first!"

Liu Qianqian nodded, cleaned up the test bench, and then followed Professor Wang to the special canteen of the Institute of Physics to eat.

Along the way, the two walked and chatted, Professor Wang knew very little about sonic weapons, along the way Liu Qianqian was talking, Professor Wang was listening, of course, in order to be able to help, Professor Wang and Professor Kong Some old professors are also active in learning sound wave knowledge, but compared to Liu Qianqian, their learning is still too shallow.