I am a super cop

Chapter 511 The Same Material

When did Lu Weiwei become 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 wonder, "Is that so?"

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

"We found no dangerous nitroglycerin, no flammable and explosive substances, and no traces of burning at the scene."

"But how did this explosion come about? It's like pressure."

Gu Chen showed him the contents of the graffiti that he repeatedly reasoned on the notebook: "Look, senior brother Wang, the only clues we could find at the scene were big rocks, piano wire tied on the glass bottle cap, and water and alcohol. .”

"These four things put together can completely present such a picture."

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

Using my good drawing skills, I drew on the blank paper the scene I had just reasoned out using my entry-level imagination.

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 immediately moved closer, staring straight at the page.

Gu Chen then marked the mouth of the bottle as sealed, and conveniently repainted a larger glass bottle on the outside.

"Gu Chen." Police officer Wang was a little puzzled, and quickly asked him: "You mean, you want to put this sealed glass bottle filled with water into this big glass bottle?"

"That's right." Gu Chen nodded, and said again: "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 wide-mouthed glass bottle and the water-filled airtight glass bottle and marked it as dry ice, and some wavy lines marked it as alcohol.

Afterwards, Gu Chen drew a lid on the wide-mouthed glass bottle, pressed a stone on it, and tied the stone firmly to the bottle cap with piano wire.

"I understand." Seeing Gu Chen's painting clearly, Lu Weiwei's reasoning just now can be reflected in Gu Chen's painting, and she smiled and said: "At this time, putting alcohol and dry ice together can reduce the temperature. to around -80 degrees Celsius."

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

Looking at the still damp bookshelf, Lu Weiwei said again: "At that time, this specially treated glass bottle was secretly placed on the bookshelf when I was on duty in Gaocheng."

"At that time, Liao Feng was inexplicably called away, so Gao Cheng was the only person in the laboratory. If he was injured, it is very likely that no rescuer could be found."

Officer Wang also walked to the bookshelf, turned around suddenly and said, "It was Zhang Hao, it was Zhang Hao who called Liao Feng away. If the murderer only targeted Gao Cheng, then he would definitely not let other people 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 to create an explosion."

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

"So that's how it is." Police Officer Wang raised the corner of his mouth, and then he said with relief: "I said, why is the person with the most murderous motive not at the scene? It turns out that he used the properties of dry ice and alcohol to have a good time with our police. , We were all deceived by him."

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

"Because in this office, there is no dry ice substance, nor alcohol. If he wants to make this explosion, he must get these two substances, and he needs to complete the arrangement in a very short time."

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

"But since there is a simulation, it will definitely reveal its feet. After all, we now know that the form of the explosion is related to the fusion of dry ice and alcohol."

"But Zhang Hao doesn't know that we know it right now, so this is also an opportunity."

"Yes." Lu Weiwei agreed [-]% with Gu Chen's opinion: "He Zhang Hao is cunning enough, but he is unlucky to meet us."

"That old man." Officer Wang suddenly looked out of the window, pointed to the outside of the door and said, "He is the only one who knows the distribution structure of Nanshan Laboratory. Let's call him over to help and investigate the nearby surveillance overnight."

"Yes." Gu Chen agreed.

Leaving the crime laboratory, Gu Chen and Lu Weiwei went to invite the old guard, and they were also led by the old guard to the lower floor of the crime laboratory, where they met Police Officer Wang.

"Here is the office where the experimental items are stored. Because they are all chemicals, the professor usually doesn't let us come in and out at will. Only when you come to me with the professor's approval slip, I will open the door for these people."

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

Lu Weiwei walked in first and turned on the light.

Then came Gu Chen, Officer Wang, and the doorman, who entered last.

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

The old doorman scratched his head and thought: "It seems that Zhang Hao was the only one who came this afternoon. He said he was going to conduct some freezing experiments and asked me to bring some alcohol and dry ice."

"You also know these things?" Lu Weiwei asked curiously.

The doorman smiled, waved his hand and said, "Hi! Do you know anything about this? I also helped the school laboratory in the early years, so I still know some things."

"It really is Zhang Hao." Gu Chen smiled at Lu Weiwei and Police Officer Wang, feeling that everyone's reasoning was correct.

Indeed, the most suspicious Zhang Hao had been to the laboratory, and the materials needed were exactly dry ice and alcohol.

This just confirmed everyone's previous suspicions.

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

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

Use it to open the desk drawer at the door, and take out a thick record book from inside.

"Come and take a look. Anyone who has been in the material room has records here, with the date and time." The old man began to flip through the latest one.

At this moment, the record of Zhang Hao receiving the materials appeared at the bottom.

This also shows that Zhang Hao was the last person to receive the chemicals before the laboratory exploded.

Afterwards, Gu Chen flipped through other records, and the time moved forward one by one.

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

Other than that, everyone else received other substances. Although there was also alcohol, Zhang Hao was the only one who received dry ice.

"That's it." Gu Chen tapped on the record book with his hands, and then quickly took out his mobile phone to take pictures of these pictures.

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

I also saw that the guard was a little curious, but Gu Chen couldn't tell her right away, so he could only smile and ask, "By the way, sir, is the surveillance on your head useful?"

"Yes, it's all useful. If it's useless, what if a thief gets in."

"Then help us get the surveillance camera out." After hesitating for a while, Gu Chen said again: "By the way, just adjust 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 fine, but the monitoring room is usually empty at night, but the machines are always on."

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

For Lu Weiwei, who often went to the dispatching room of the sub-bureau, she knew the various operations of these monitoring instruments by heart, and there was no big problem.

The old doorman immediately took another key from the key board, pointed to the end of the corridor and said, "The monitoring room is at the stairs, you should check it yourself."

"Thank you uncle."

After a short farewell, they opened the door of the monitoring room.

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

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

The old man who had been wearing a military overcoat and standing at the door yawned from time to time, his eyes were bloodshot.

When he saw this group of energetic policemen come out, he was relieved and asked, "Is there anything else you need to help?"

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

"It's not far from here, it's the neighborhood over there." In order to point out the direction for the police in detail, the doorman pointed to a building on the side and said, "See? The far left of that building is the 27th floor."

Lu Weiwei smiled: "I said, sir, you can remember it really clearly, even the exact location of Zhang Hao's house."

"Zhang Hao didn't tell me by himself. He likes to show off. I may not remember it once, even twice or three times. But when he just told me the location of his home, he said it ten times before and after. time, so I will remember it." The doorman also told the truth.

Thinking about the fruitful harvest tonight, Gu Chen is also very happy from the bottom of his heart.

The doubts at that time seem to have been solved now, and everyone also collected various evidences that Zhang Hao took the materials at night.

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

"Junior 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 tomorrow?"

"No, it should be today, and it should be tonight." Gu Chen had no room for negotiation.

Police officer Wang also agreed: "The more this is the case, the less concentrated Zhang Hao's energy is. At this time, taking him back to the Furong branch for interrogation may have better results."

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

After the three of them bid farewell to the guard, they drove together to the nearby Meilin community.

This is a mid-range residential area, the house price ranks in the middle of Jiangnan City, and the property is not very concerned.

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

He also heard the doorbell ringing constantly outside the door. Zhang Hao, who was sleeping on the bed, could no longer calm down. He opened the door with a look of anger on his face.

But when he saw three policemen coming to the door, he froze for a moment, then frowned weakly and asked: "Comrade policeman, what time is it? Are you still letting people sleep?"

Seeing that Gu Chen, Lu Weiwei and Officer Wang were silent, Zhang Hao asked again, "What are you doing at my house?"

Gu Chen showed him his people's police certificate, and then said: "I am Gu Chen from the third criminal investigation team of the Furong Branch. An explosion occurred in the Nanshan laboratory tonight. Your colleague Gao Cheng was seriously injured and is currently receiving treatment in the hospital. , we need your assistance in the investigation."

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

Zhang Hao was a little unbelievable, and asked weakly: "What questions do you have, can you talk about it here?"

Gu Chen shook his head: "No."

Zhang Hao was a little desperate, even angry.

After all, knocking on the door in the middle of the night interrupts one's dream, and no one will agree to it.

So Zhang Hao could only compromise and said: "Okay, you wait for me first, I will go get a piece of clothing."

25 minutes later……

Furong Sub-bureau, Interrogation Room No. [-].

When Zhang Hao walked into this cold interrogation room, he couldn't help but feel his heart skip a beat, and then Gu Chen asked him to sit on the interrogation chair.

Between the two parties, only a chandelier was turned on, making the atmosphere extremely quiet, and even the breathing of the other party could be clearly heard.

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

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

"Report your age and ID number." Gu Chen said again.

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

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

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

He never thought that the police would be interested in these two things, and he was a little flustered.

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

Zhang Hao said with a smile: "Is... what's the problem with this? I'm doing a freezing experiment recently, and I need some alcohol and dry ice as materials."

"You're lying." Lu Weiwei, who had already seen through everything, immediately said through the light hanging in the middle of the interrogation room: "We have already conducted an investigation in the laboratory, and from the results of the investigation, the explosion is very likely to be dry ice. and alcohol."

"What...how do you say this?" Zhang Hao pretended to be stupid and looked at Lu Weiwei inexplicably.

Logically speaking, the police's knowledge of these chemical aspects should be weak.

But judging from Lu Weiwei's tone, it seemed that the police had found a reliable clue.

Gu Chen took out his mobile phone, walked up to Zhang Hao, and showed him the picture on the phone: "This is the record of our investigation of your receipt of materials."

"Most of those times, you got alcohol and dry ice, but the others didn't."

"You know, the 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 cubes, and as the pressure rose, you tied the cap of the wide-mouthed glass bottle with piano wire. big Stone."

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

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

"But you put this glass bottle next to the bookshelf near Gaocheng. The huge power generated by the explosion hit the unsuspecting Gaocheng, so you passed out on the ground..."

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

Zhang Hao was restless, looking at Gu Chen from time to time, and the ground from time to time.

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

However, what surprised him was that Gu Chen seemed to know these experiments well, no different from professionals.

After saying this, Zhang Hao didn't know whether to laugh or cry: "I don't know what happened in the lab tonight, but it definitely has nothing to do with me."

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

Seeing that Zhang Hao said a lot, but Gu Chen didn't seem to buy it, he continued to hold the picture in his hand and said, "I checked, and these days you are the one who frequently receives dry ice and alcohol. You can get it anywhere."

"And among all the people, you are the only one who has conflicts with Gaocheng. If we don't arrest you, who will we arrest?"

"This..." As if realizing that the police were quite clear about his background, Zhang Hao froze again, shrinking back.

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

"We know that you and Gao Cheng are dating a girl named Han Jing. She is also an assistant in your laboratory. You and Gao Cheng used to be at odds."

"But it's ridiculous. Han Jing seems to be more interested in Gaocheng, so there is an irreparable gap between you."

"As long as Gao Cheng is here, you will not be safe for a day, and you have to watch Gao Cheng and Han Jing dating. You feel uncomfortable."

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

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

……

(End of this chapter)