The mountain was already empty, and Du Lin no longer had to hide all his strength, and the whole person suddenly relaxed a lot.

Looking at the zombie firmly controlled by the metal shell, and then looking at the big clock made next to it, Durin said to himself:

"Don't look at your zombie if you don't bury it in the sky and don't collect it on the ground, today, I have to kill you!"

Duhrin stepped on the five-element chart, his left hand held the five-element candlestick, and his right hand pointed to the big clock,

"Up!"

I saw that the big bell was hanging in the air, facing the zombie in the metal shell, but it did not fall. Durin shouted again: "Thunder!"

A dark cloud appeared at the mouth of the bell, and thunder and lightning were brewing in the dark cloud, because this time the main means of attack was thunder, so Du Lin did not let the lightning split down to save mental power.

As soon as his right hand fell, the bell fell to the ground, and the thundercloud and zombies were buckled under the bell. Then, there was a loud bang like a hammer and a drum.

Durin stood more than ten meters away from the bell, and the sound was still inside the bell, even so, Durin was still upset by the sound.

When humans are in an environment where there is sound above 120 decibels without any protection, they will feel discomfort or damage the hearing system, and when the volume rises above 150 decibels, humans in this environment will experience eardrum rupture and bleeding, loss of hearing, and even mental disorders, which will lead to death if they stay for a while.

But the bell is not a human, but an invulnerable zombie, and if he wants to kill him, Durin needs to make a bigger move.

Du Lin just used his mobile phone to check the relevant information, the noise of the space shuttle when it took off was about 190 decibels, and the most sound that human beings could make at present was the "Big Ivan" bomb of the woolly bear country, and the sound when detonated reached 224 decibels, and according to scientists, the largest noise ever appeared on the earth was 275 decibels, because an asteroid fell on the earth, and on that day, the dinosaurs on the earth were extinct.

Du Lin estimated that if he wanted to kill this zombie, he would have to make a sound of about 230 decibels, but this movement is estimated to be heard for hundreds of miles, and if he really wants to make it, Du Lin himself can't stand it.

You know, according to the conversion formula given on the Internet, the sound of 230 decibels is equivalent to the pressure of 100,000 kilopascals on the eardrum of a person......

Therefore, Dühring had to find a way to control the influence of sound within a small range, and using a large bell to close the sound was only one of the measures, and Dühring also needed a more effective way to prevent the sound from escaping.

Duhring pondered in his heart: to put it bluntly, the production of sound is the vibration of various tiny particles in the air, and sound cannot be transmitted in space, because there is no air, so if the air can be evacuated......

Yes, it's a vacuum, and Durin now needs to create a vacuum environment, so that the sound can be isolated, but not all the air in it can't be evacuated, otherwise the thunder won't reach the zombies.

"The wind rises!" Durin urged the force of the wind to form a whirlwind around the bell, and then extracted a layer of metal from the outer part of the bell to make a thin metal cover, and left a ventilation hole at the top, and after the whirlwind evacuated the air between the metal cover and the bell, the ventilation hole was immediately closed, and now a vacuum environment was formed between the metal cover and the bell.

In this way, no matter how tossing inside the bell, because there is no air as a medium outside, no matter how much movement there is, it will not have the slightest impact on the outside.

Now, Durin can let go of his hands and feet, and urge the power of thunder with all his strength to attack zombies with sound waves, and Durin also tries to attack with sound waves of different frequencies, in case which frequency can form a resonance, it can theoretically form an exponential attack effect.

This time, Du Lin really used all his strength, he was almost constantly using his spiritual power to urge the power of thunder, sweat was pouring down on his head, because of the overdraft of his mental power, he had a splitting headache, I don't know how long it took, his eyes were dark, and he fainted......

By the time Doolin opened his eyes again, it was already dark, and the members of the second team had set up several simple tents out of tarpaulins and wood in the small square (because the tent poles were made of metal, which had been dismantled by Dührin along with the Humvee), and Dührin was now lying in a makeshift tent. Touching both hands, it's okay, the five-element candlestick is still there.

Du Lin shook his still drowsy head, and said in his heart, I haven't bothered so much in more than 1,400 years, and it's really uncomfortable to overdraw my mental strength, so I won't do it next time.

But after sobering up, Du Lin found that although his mental power had not fully recovered, the upper limit of his mental power was higher than before, and his five senses were already very sharp before, but now it seems that the range of perception is larger than before, and the degree of perception is more accurate. Although he was under a tarpaulin now, there were several people outside, and he didn't need to look at them, just by listening to the sound and smelling the smell, he could make an accurate judgment.

Taking two deep breaths, Durin sat up, but found that the tent was too low, and when he sat up, the tarpaulin was put around his head, bringing the whole tent up.

The members of the second team of the operation, who were busy lighting a fire and cooking outside, saw that Du Lin was awake, and hurriedly surrounded him and lifted the tarpaulin on Du Lin's head.

"Doctor Du, how are you, is there anything wrong?" asked Xu Du with concern.

"Thanks, I'm fine, what happened to the zombies?"

Xu Du said: "I think it should be dead, because there is no movement in that metal cover, but we are afraid that the corpse poison is still there, so we dare not open it." We have contacted Mr. Yu, and support is on the way, and it will arrive soon. ”

"Let's go, I'll take a look. Durin stood up and walked towards the daytime battlefield on the mountain.

In the night, a few bonfires were lit around the metal cover, and the cover was shining, and the two team members were sitting around the bonfire, eating, and when they saw Du Lin and Xu Du and others coming, they hurriedly got up and said hello:

"Dr. Du, are you awake?"

"Well, I'm fine, you've worked hard. ”

"We have something to work hard, and we are lucky to be able to survive. However, Dr. Du, that wolf dog of yours is really a god, seeing that we have nothing to eat, he drove several rabbits over, and those rabbits came by themselves, as if they deliberately wanted us to eat them, and they just crashed into the rocks and died, which made us all a little embarrassed to swallow. ”