When did I feel like Lu Weiwei became so smart? Officer Wang instantly felt that he was a little marginalized?

He looked at Lu Weiwei, then at Gu Chen, and couldn't help but say, "Is that so?"

"It should be. Gu Chen didn't say anything too deadly, but just analyzed the problem from his own perspective: "Senior Brother Wang, I think so. ”

"We didn't find dangerous nitroglycerin, flammable or explosive substances, or burning. ”

"But how did the explosion happen? It was, for example, pressure. ”

Gu Chen showed him the content of his repeated reasoning and graffiti in the transcript: "Senior Brother Wang, look, the only clues we can find at the scene are big stones, piano filaments tied to the lid of glass bottles, and water and alcohol. ”

"Together, these four things can present such a picture. ”

In order to better and more directly reflect his reasoning, Gu Chen turned the transcript to a blank page again.

Using his good drawing skills, he drew the scene that he had just deduced with his entry-level imagination on a blank piece of paper.

Gu Chen first drew a glass bottle, and then drew some wavy lines on the mouth of the glass bottle, marking it as water.

Lu Weiwei suddenly got closer, and her eyes looked straight at the page.

Gu Chen then marked the mouth of the bottle as sealed, and easily redrew a larger large-mouth glass bottle on the outside.

"Gu Chen. Officer Wang was a little puzzled and hurriedly asked him, "What do you mean to put this sealed glass bottle filled with water into this large-mouth glass bottle?"

"That's right. Gu Chen nodded, and said, "But now is the most critical time, because I want to put dry ice and alcohol around the sealed glass bottle." ”

According to his own dictation, Gu Chen drew some cubes between the large-mouthed glass bottle and the sealed glass bottle filled with water, labeling dry ice, and drawing some wavy lines as alcohol.

Subsequently, Gu Chen painted the lid of the large-mouth glass bottle, pressed a stone on it, and firmly tied the stone to the cap with piano wire.

"I see. Looking at the clarity of Gu Chen's paintings, Lu Weiwei's reasoning just now could be reflected in Gu Chen's paintings in an instant, and she immediately smiled and said: "At this time, when alcohol and dry ice are put together, the temperature can instantly drop to about -80 degrees Celsius. ”

"And the water in the glass bottle freezes, expands in volume, and then explodes. ”

Looking at the bookshelves that were still a little damp, Lu Weiwei said again: "And at that time, this specially treated glass bottle had been secretly placed on the bookshelf when I was on duty in Gaocheng. ”

At that time, Liao Feng was inexplicably called away, so there was only Gao Cheng in the laboratory, and if he was injured, it was very likely that he would not be able to find someone to rescue. ”

Officer Wang also walked to the bookshelf, suddenly turned around and said, "It's Zhang Hao, it was Zhang Hao who called Liao Feng away, if the person targeted by the murderer is only Gao Cheng, then he will definitely not let anyone else stay in the laboratory." ”

"Yes, it's Zhang Hao. Gu Chen also snapped his fingers, and then said: "This can explain why when Gao Cheng was injured, Zhang Hao was eating with Liao Feng and other friends." ”

"Because he cleverly used the reaction time difference between dry ice and alcohol to stagger the time of the explosion. ”

And Liao Feng and other Zhang Hao's friends became witnesses to his alibi in a daze. ”

"I see. The corners of Officer Wang's mouth rose, and then he said with relief: "I said, how could the person with the most motive to kill not be at the scene, it turns out that he used the attributes of dry ice and alcohol to have a good time with our police, and we were all deceived by him." ”

Gu Chen also said: "For now, the most important thing for us is to find Zhang Hao's evidence. ”

"Because in this office, there is no dry ice at all, and there is no alcohol, and if he wants to make this explosion, he has to get his hands on both substances, and he has to set them up in a very short time. ”

"So I think he should have secretly simulated it a few times, otherwise it wouldn't have gone so well. ”

"But if there is a simulation, it will definitely be exposed, after all, we now know that the form that caused the explosion is related to the fusion of dry ice and alcohol. ”

"But Zhang Hao doesn't know that we know at the moment, so this is also an opportunity. ”

"Yes. Lu Weiwei agreed with Gu Chen's opinion 200 percent: "He Zhang Hao is cunning enough, but he is unlucky when he meets us." ”

"The old man. Officer Wang suddenly looked out the window, pointed to the door and said, "He is the only person who knows the distribution structure of the Nanshan laboratory, let's call him over to help, and investigate the nearby surveillance overnight." ”

"Yes. Gu Chen agreed.

Leaving the laboratory where the crime occurred, Gu Chen and Lu Weiwei went to invite the doorman uncle, and the two of them also came to the bottom floor of the crime laboratory under the leadership of the doorman and met with Officer Wang.

"This is the office where the experimental items are stored, because they are all chemicals, the professor usually doesn't let us go in and out at will, and I will only open the door for these people if they come to me with the professor's approval. ”

While explaining, the doorman also took out the key from himself, and then opened the door of the room in the storage area.

Lu Weiwei walked in first and turned on the light.

Followed by Gu Chen, Officer Wang, and the doorman entered last.

"Has anyone been here this afternoon?" asked Gu Chen.

The old man of the doorman scratched his head and thought: "It seems that only Zhang Hao has come in the afternoon, saying that he is going to conduct some freezing experiments, and asked me to take some alcohol and dry ice." ”

"You know these things too?" Lu Weiwei was curious, not to want it.

The doorman smiled, waved his hand and said, "Hey, what do you know, I also helped in the school laboratory in my early years, and I still know some things." ”

Sure enough, it was Zhang Hao. Gu Chen smiled at Lu Weiwei and Officer Wang, feeling that everyone's reasonable reasoning was not wrong at all.

It is indeed the most suspicious Zhang Hao who has come to the laboratory, and the materials he needs are precisely dry ice and alcohol.

This also just confirms everyone's previous suspicions.

"Uncle. Gu Chen smiled and said to him, "Zhang Hao took away the dry ice and alcohol in the afternoon, do you have a record of this?"

"Yes, both. The old man responded very cheerfully, and then found a marked one on a board of keys.

Use it to open the desk drawer at the doorway and pull out a thick notebook from inside.

"Come and see, all the things that have been to the material room are recorded here, and the date and time are there. The old man began to flip through the latest one.

At this moment, the record of Zhang Hao's receipt of materials appeared at the bottom.

This also shows that Zhang Hao was the last person to come to collect the chemicals before the explosion in the laboratory.

Subsequently, Gu Chen flipped through the other records, and the time was advancing in turn.

It is not difficult to see that in just half a month, Zhang Hao has gone to the material room many times to get alcohol and dry ice.

In addition, everyone else received other substances, although there will also be alcohol, but Zhang Hao is always the only one who receives dry ice.

"This is it. Gu Chen tapped his hand on the record book, and then quickly took out his mobile phone and took pictures of these pictures.

The doorman was a little puzzled, and hurriedly asked Gu Chen: "Comrade policeman, what do you want these for? Is it to collect evidence? Do you suspect Zhang Hao?"

I also saw that the doorman was a little curious, but Gu Chen couldn't tell her immediately, so he could only smile and ask, "By the way, uncle, is the monitoring on your head useful?"

"Yes, it's all useful, it's useless, what if you get into the thief. ”

"Then help us get the surveillance out. After hesitating for a moment, Gu Chen said again: "By the way, just transfer the video of Zhang Hao receiving the materials, as for the time, check it according to the registration date." ”

"This ......" The doorman was a little embarrassed, but he still agreed: "That's okay, but the monitoring room is usually empty at night, but the machines are all on." ”

"It's okay, we can do it ourselves. Lu Weiwei said.

For Lu Weiwei, who often goes to the dispatch room of the sub-bureau, she has long known the various operations of these monitoring instruments, and there is no big problem.

The old man of the doorman immediately took off the other key from the key board, pointed to the end of the corridor and said, "The monitoring room is at the top of the stairs, you can check it yourself." ”

"Thank you, uncle. ”

Since after a short goodbye, open the door of the monitoring room.

Then Gu Chen used the date and time he took to retrieve Zhang Hao's various pictures.

After finishing the work, it was already four o'clock in the morning.

The old man who has been dressed in military uncles and standing at the door yawns from time to time, and his eyes are bloodshot.

When he saw these energetic policemen come out, he asked with relief, "Is there anything else you need help with?"

"Where is Zhang Hao's home?" asked Officer Wang.

"It's not far from here, it's the neighborhood over there. In order to give the police a detailed direction, the uncle outside the door specially pointed to a building on the side and said: "Do you see? The far left of that building, the twenty-seventh floor." ”

Lu Weiwei smiled: "I said uncle, you remember it so clearly, even the specific location of Zhang Hao's house is clear." ”

"It's not Zhang Hao himself who told me, he loves to show off, I may not be able to remember it once I hear it, not twice or three times, but when he just told me the location of his house, he said it no less than ten times before and after, so I remembered it. "Uncle Janitor is also telling the truth.

Thinking about tonight's harvest, Gu Chen was also happy in his heart.

The doubts at that time, in the current view, seem to have been solved, and everyone also collected all kinds of evidence for Zhang Hao to take the materials at night.

In this way, even if he wants to quibble, it will be full of mistakes.

"Senior Brother Gu. Lu Weiwei walked up to Gu Chen and showed him her lady's watch: "It's almost dawn now, do you want us to catch it again tomorrow?"

"No, it should be today, and it should be that night. "Gu Chen has no room for negotiation.

Officer Wang also agreed: "The more this time, the less focused Zhang Hao's energy is, and at this time, it may be better to bring him back to the Furong Branch for interrogation." ”

"Then it's decided. Gu Chen also said.

After the three of them said goodbye to the uncle outside the door for a short time, they drove to the surrounding Meilin community together.

This is a mid-range community, with a medium housing price ranking in Jiangnan City, and the property is not very attentive.

When Gu Chen parked the car at the door, after explaining the situation to the security guard on duty, he went directly to Zhang Hao's house.

also heard the doorbell ringing outside the door, Zhang Hao, who was sleeping on the bed, couldn't be calm anymore, and he opened the door with a look of anger.

But when he saw that there were three policemen at the door, he was stunned for a moment, and then he frowned and asked weakly: "Comrade policeman, what time is it?

Seeing that Gu Chen, Lu Weiwei and Officer Wang didn't speak, Zhang Hao said again: "What are you doing at my house?"

Gu Chen showed him his people's police card, and then said: "I am Gu Chen from the Criminal Investigation Group 3 of the Furong Branch, there was an explosion experiment in the Nanshan Laboratory tonight, your colleague Gao Cheng was seriously injured and is currently being treated in the hospital, we need your assistance in the investigation." ”

"So, come with us. Lu Weiwei also said.

Zhang Hao was a little incredulous, and asked weakly: "Do you have any questions, can you talk about them here?"

Gu Chen shook his head: "No." ”

Zhang Hao was a little desperate, even angry.

After all, knocking on the door late at night interrupts people's dreams, and no one agrees.

So Zhang Hao could only admit: "Okay, you wait for me first, I'll go get a piece of clothing." ”

Twenty-five minutes later......

Interrogation Room 1 of the Seremban Substation.

When Zhang Hao walked into this cold interrogation room, the whole person couldn't help but chuckle in his heart, and then was asked by Gu Chen to sit on the interrogation seat.

In the middle of the two parties, only a chandelier was turned on, which made the atmosphere extremely quiet, and even the other party's breathing could be heard clearly.

"What's your name?" Gu Chen opened the transcript and asked him.

Zhang ...... Zhang Hao. Zhang Hao replied quietly, but with a slight resistance.

"Age, ID number. Gu Chen said again.

Zhang Hao could only do as he was told, impatiently completing these unbelievable records.

It was also after understanding the input of all the basic information that Gu Chen looked at the eyes of Officer Wang and Lu Weiwei, and then said, "Then let's start, let me ask you a question first, why do you often go to the material room to get dry ice and alcohol?"

Seeing the first question, Gu Chen hit the nail on the head, and Zhang Hao was stunned for a moment, but he quickly calmed down.

He didn't expect that the police would be interested in these two things, and the whole person was a little flustered.

"Zhang Hao, answer me. Gu Chen continued to remind.

Zhang Hao smiled: "This ...... I've been doing freezing experiments recently and need some alcohol and dry ice as a material. ”

"You lie. Lu Weiwei, who had already seen through everything, suddenly said directly through the light hanging in the middle of the interrogation room: "We have already done an investigation at the laboratory site, and judging from the results of the investigation, the explosion is likely to be caused by dry ice and alcohol." ”

"This ...... How do you say this?" Zhang Hao pretended to be stunned and looked at Lu Weiwei unconsciously.

It stands to reason that the police's knowledge of these chemical aspects should be weak.

Judging from Lu Weiwei's tone, it seems that the police have found reliable clues.

Gu Chen took out his mobile phone, walked in front of Zhang Hao, and showed him the pictures in the mobile phone: "This is our record of investigating the materials you received." ”

"Most of the time, you've picked up alcohol and dry ice, but others haven't. ”

"You know, this explosion at night happened to be the fusion of alcohol and dry ice, causing the water in the sealed glass bottle to turn into ice, and as the pressure rises, you tie the big stone with piano wire on the cap of the glass bottle. ”

"And just after the dry ice and alcohol were mixed for a long time, the temperature began to drop to -80 degrees Celsius, and the water in the glass bottle froze and expanded, causing an explosion. ”

"But at that time, Gao Cheng was the only one in the laboratory, because you called his colleague on duty Liao Feng away, and he was sitting by the bookshelf at that time. ”

"But you put this glass bottle next to the bookshelf near Gao Cheng, and the huge power of the explosion made the unsuspecting Gao Cheng attack, so he fainted to death on the ground......

Gu Chen combined himself into an explosion experiment based on the objects at the scene, and listed them clearly with Zhang Hao.

Zhang Hao's whole person was restless, his eyes sometimes looked at Gu Chen, and sometimes looked at the ground.

When Gu Chen talked about the key point, Zhang Hao pricked up his ears and listened carefully.

However, what surprised him was that Gu Chen seemed to know all about these experiments, and there was no difference from his professional understanding.

After saying this, Zhang Hao directly cried and laughed: "I don't know what happened in the laboratory tonight, but this matter must have nothing to do with me." ”

"I was eating and drinking with my friends at the time, Liao Feng can prove it, and later I learned in the work group that Gao Cheng, who was on night duty, was admitted to the hospital for no reason. ”

Seeing that Zhang Hao said a lot, Gu Chen didn't seem to buy it, and continued to take the picture in his hand and said: "I've checked, you are frequently receiving dry ice and alcohol these days, this kind of thing doesn't mean that you can get it casually outside." ”

"And among all of them, you are the only one who has a conflict with Gao Cheng, who do we not arrest you?"

"This ......" seemed to find that the police were quite clear about his old background, Zhang Hao's whole person was stunned again, and his body shrank back.

With his head down, he said with a tangled expression: "What do you all know?"

"We know that you and Gao Cheng are both dating a girl named Han Jing, who is also an assistant in your laboratory, and you used to have some incompatibility with Gao Cheng. ”

"But it's ridiculous, Han Jing seems to be more interested in Gao Cheng, so there is an irreparable estrangement between you. ”

"As long as there is Gao Cheng on this day, you will not be able to be stable for a day, and you will have to watch Gao Cheng and Han Jing interact, and you will feel uncomfortable. ”

also found that when he mentioned this, it seemed to touch Zhang Hao's pain point.

Zhang Hao's whole face suddenly became ugly, and the fists in his hands began to creak.

......