Rebirth 78, the beginning of the marriage was broken off by the female educated youth

Li Xiangnan knew that Ruobai and Xu Qiluo were currently doing their best to investigate the case of Zhang Jingyang's senior brother Zhang Zhisheng being murdered.

Only a few days have passed and they've come looking for us. It's impossible to say that nothing happened.

Seeing how anxious these two people were, Li Xiangnan concluded that Ruobai must have something to ask him.

Sure enough, when Qin Ruobai saw Li Xiangnan coming, he gave him a wink and quickly walked to the side.

"Xiangnan, we have been sorting out clues about Senior Brother Zhisheng's case these days. The bureau has sent many people to sort out his social relationships, but there is still no clue. So I thought of bringing the evidence from the scene to you to see if you can think of some way to help find the direction of the investigation!"

Want to discuss the direction of the case with me?

Li Xiangnan felt a little flattered!

But he came from the future, and he knew that even in the technologically advanced 21st century, when the police investigate criminal cases, they will contact and communicate with people from all walks of life, and when necessary, they will respect the opinions of various criminal consultants in the bureau.

Sometimes, even a casual reminder from an industry elite may be the key to solving the case.

Li Xiangnan turned his head and saw that Xu Qiluo was holding a net bag filled with stuff. He frowned and asked, "Do you want to continue analyzing the materials at the scene and see if there is a breakthrough?"

Qin Ruobai nodded and said anxiously: "To be honest, the direction of the investigation in the bureau is still very rough. Many people in the bureau have discussed it many times. They are all unfamiliar with the substance in the basin. No one can say what it is! You gave a general idea when you contacted me that day, and Director Zhang asked me to come over and find you to confirm it! See if we can find any clues from this aspect!"

Hearing this, Li Xiangnan immediately understood.

At present, the development of forensics and judicial identification in the domestic public security is not perfect. The trace examination department has not even been established in some areas. It is indeed in the initial stage.

Without the appropriate instruments to analyze these physical evidences, it is naturally impossible to directly form a strong reference for the case.

The first physical forensic identification institution in the country was established in 87, which was nine years later.

If we don't find a way to analyze the substance in the basin where Senior Brother Zhisheng was attacked, we won't be able to track down the specific murderer. This is a very realistic problem.

"Okay! I'll find a way to deal with this!" After thinking it through, Li Xiangnan comforted the two of them. From a distance, he saw Wang Defa, Hu Yinglong and three others walking towards him.

"Fuck, Xiao Li, you're here to chat... so early in the morning?" Wang Defa walked over angrily and grabbed his neck, his expression full of envy and jealousy.

"Brother Nan, sister-in-law...hello sisters!" Hu Yinglong saw the three of them from a distance, and when he came over, he was so sweet to them.

Qin Ruobai smiled lightly and said generously: "You are Xiangnan's roommates, right? My name is Qin Ruobai, and I'm his friend!"

"My name is Hu Yinglong! They call me Brother Long!" Hu Yinglong quickly grinned and stood at attention.

"Duan Sijiu!" Old Duan, who was not good at dealing with women, smiled shyly and did not dare to say anything more.

Lu Chen scratched his head and introduced himself: "My name is Lu Chen! I'm from Xichuan!"

Wang Defa said jokingly: "My name is Wang Defa, from Yanjing! They all call me Brother Fa! Or Ward Fake!"

"Haha! Defa, why are you still so poor? You're still so frivolous even after going to college!" Qin Ruobai was amused by these buddies and laughed, his eyes almost narrowed into crescents.

After Xu Qiluo greeted a few people, he started eating watermelon and clicking his tongue softly.

Students passing by on their way to the teaching building for classes were very surprised to see two police uniforms standing there abruptly. They stared at them frequently with awe and curiosity in their eyes.

Wang De noticed the people around him looking at him, and asked in confusion, "Xiao Qin, why are you looking for Xiao Li so early in the morning?"

Li Xiangnan poked him, "It's business, stop joking. Where is Old Ye's class this morning? I need his help with something for Senior Brother Zhisheng!"

"It's the lecture hall, right? He seems to have two classes on Mao Zedong Thought!" Wang Defa grinned and stopped joking!

"Okay! Brother Duan, please answer it for me, I'll go find him!" Li Xiangnan waved his hand, drove the few people away, and led Qin Ruobai and the other person to find Ye Buping.

Ye Buping had just arrived at the classroom and was discussing something with the teacher on the stage.

"Director Ye!" For fear of causing unnecessary misunderstandings, Li Xiangnan did not let Qin Ruobai and the others in and waved at him.

"Xiao Li?" Ye Buping was very surprised. Why did this guy come to see him so early in the morning? He said something to the teacher and walked out quickly. As soon as he went out, he saw two uniforms and was immediately startled.

"Old Ye, why are you so nervous? You haven't done anything bad." Li Xiangnan laughed and quickly introduced: "This is my friend. He is investigating a case. Can you help me contact the Physics Department? I want to use the mass spectrometer!"

Ye Buping wiped his sweat and said with lingering fear: "You are really good at making fun of others!"

After he finished speaking, he greeted Qin Ruobai and the others. He knew what a mass spectrometer was for, but it was not convenient for him to ask about the case, so he made a promise and said, "Okay, I'll go ask for a leave!"

After saying that, he went back into the house.

Li Xiangnan gave Qin Ruobai a wink, and the latter understood and stood at the door of the classroom.

The tutor inside was still a little unhappy, but when he turned his head in confusion and saw Qin Ruobai in uniform, his natural awe immediately made him smile and he agreed to Lao Ye's request and decisively approved the leave.

Several people immediately followed Ye Buping to the Department of Physics and found the person in charge of the laboratory. When they saw that it was a comrade from the public security department who wanted to borrow equipment and had relevant letters of introduction, they agreed without saying a word.

The only thing he asked was that Ye Buping be responsible for the safety of the laboratory and not to run away if anything happened. Old Ye didn't want to stay at first, but after being stimulated by these words, he stayed at the door as a security guard and emergency responder.

In the 60s, my country's Institute of Physics developed the first mass spectrometer, a 50-1 electron magnetic spectrometer.

Later, the North Branch produced dozens of magnetic mass spectrometers, some of which were used by the factory itself and some were donated to important scientific research institutions such as the Department of Physics of Yenching University.

The core application of mass spectrometry is to separate isotopes and accurately determine their atomic masses and relative abundances.

At the public security level, it can be directly used for the identification and quantification of poisons, and can determine the mechanism of action of poisons on organisms, which is helpful for toxicological research and the investigation of poison incidents.

Li Xiangnan had come into contact with mass spectrometers many times in later life, but this early electron magnetic spectrometer was still unfamiliar to him. Fortunately, the principles were similar. After careful study, he figured out the general working principle.

Qin Ruobai and Xu Qiluo, who were standing by as assistants, put on gloves and had already peeled off some of the substance on the basin and placed it on the corresponding containers.

Ye Buping stood on tiptoe at the door and watched Li Xiangnan operating the instrument meticulously. He was really curious and anxious.

As time passed, the three people could visibly see that Li Xiangnan's brows were tightly furrowed.

This was a rare occasion for the three people to see Li Xiangnan showing such a solemn expression.

"What's wrong? Xiangnan!"