Chapter 360: The Huge Difference

In the afternoon, Yang Limin was also busy in the laboratory, and several people hurriedly went to have a meal after work, and came back again to continue to be busy.

A bunch of people have crowded the already small laboratory, and what tools they want are often passed on.

By eight o'clock in the evening, all kinds of tests were basically completed, but the rest was extremely critical, Yang Limin assigned the work, a group of two, and began to compare the data.

What Yang Limin has to do now is to use the most standard data to compare the inspection data of various samples in production, how much difference there is, he has affirmed that the reason why there is such a big difference in finished products is definitely the problem of raw material purity, otherwise there will be no problem with the finished product in the laboratory but the finished product does not meet the requirements in the actual production, and the reason why the factory did not find this problem, it turned out that they had never done a complete experiment.

In everyone's mind, the raw materials are produced in the state's regular factories, which is naturally not wrong, and the data reports that have been inspected by special departments will definitely not be falsified, so that no one has ever doubted the problem of raw materials.

Yang Limin can't just say empty words, that is not convincing at all, and he also wants to help Niu Fusheng really find out the problem.

There is no harm if there is no comparison, and as the comparison between the people slowly progresses, everyone begins to sweat on their foreheads, because according to the comparison, the purity of the raw materials used in the original production and the purity of the raw materials in the packaging instructions are very different, not to mention the purified medicines.

Because of the large number of people, the time to compare data and phone bills is not long, and it will all be over in less than two hours, but at this moment their hearts are cold, there is really no harm if there is no comparison!

Yang Limin looked at the data, almost most of the drugs have the difference between the actual purity and the purity of the packaging description, and the most serious is the difference in the purity of concentrated sulfuric acid, which is only 80% of the stated purity, which also causes the follow-up process to be not in place.

Yang Limin said: "Several of them have seen the difference between the data, so they should also be aware of the problem, right?"

Wu Dawei raised a question: "Xiao Yang, I believe that the data can tell the story, but I have another question, since the difference is so big, it is said that the quality and quality of the products produced should be very poor, but the actual result does not have such a thing, what is the reason?"

Hearing Wu Dawei's question, the others also turned their heads to look at Yang Limin, and Wang Hongshan also nodded and said: "Yes, if there are problems with the unification of raw materials, there will definitely be big problems with the quality of finished products, and it is definitely not just such a problem." And in the finished products produced in the factory, there are not many defective products!"

Yang Limin smiled and said, "Deputy Factory Director Wang, Section Chief Wu, this question you asked is very correct, this is an inference that contradicts our test results. So I want to ask you, do any of you know how the old technicians in the workshop deal with some anomalies in production, such as the actual use of concentrated sulfuric acid with the largest difference in data. ”

Wu Dawei seemed to remember something, but before he could say it, Niu Fusheng said to Wang Hongshan: "Lao Wang, you go to the house of Master Yu Dayou, who is sour, call him to the house, let him come and ask him to explain the actual operation, maybe you will be able to know the answer." ”

Wang Hongshan and Yu Dayou are considered fellow villagers, and they usually have a good relationship, and when they heard Niu Fusheng say this, they didn't shirk it, got up and walked out.

Concentrated sulfuric acid is a chemical raw material that must be used in the pickling process, mainly with potassium dichromate or dichromium acid, sodium acid configuration acid, used to borrow the PH value of leather, roughly speaking, the production and processing of leather can be said to be a process of reducing PH value. Each process serves this purpose, and of course it also has the effect of increasing performance in other aspects.

Pickling, in the tanning industry, is a process in the preparatory stage. The bare skin after the enzyme is soaked in a mixed solution of sulfuric acid and table salt. It can make the leather fiber develop, and the tanning material is easy to penetrate, so the leather made is relatively soft and delicate. Generally, light leather must be pickled. After pickling, it is mostly tanned by chrome tanning. Sometimes the plant is also acidified before tanning to achieve the purpose of fast tanning.

The chrome tanning agent is configured to use concentrated sulfuric acid.

Conventional chrome tanning requires acid to adjust the pH of the skin. The pickling process increases the use of materials, increases the difficulty of process control, and has an adverse impact on the environment. A large amount of neutral salts need to be used when macerating acid, otherwise the skin will be "sore", which is not conducive to the penetration of chrome tanning agent in the initial stage of tanning, and seriously damages the strength of the skin. If the amount of neutral salt is too large, it will make the skin dehydrated, flattened and not plump. In the later stage of tanning, the tanning agent and skin collagen are mainly combined, and at this time, it is necessary to neutralize and remove acid, so that the collagen carboxyl group is dissociated and the chromium tanning agent molecule is increased, but if the alkali extraction operation is slightly improper, it is easy to have quality problems such as rough grain surface and chromium spots.

The fundamental reason why leather is soft is that when tanning, the leather simulation oil with a good combination with leather fibers is introduced into the interior of animal skin to form an oil film that fully covers the surface of the skin fibers, that is, the skin fiber surface is separated by a layer of skin simulation oil film of appropriate thickness, so that the friction between the leather internal fibers is equivalent to the friction of oil molecules, so the leather will be very soft. Its principle is similar to that of sponge, the difference is that the inner surface fibers of the dermis are separated by an oil film, so that the inside of the dermis has sliding pores, but its pores are smaller than that of sponges, and the distribution of fibers on the inner surface of the dermis is not as regular as that of sponges. However, due to the introduction of the oil inside the leather in the natural state, it will slowly volatilize and lose over time, or due to other reasons the oil film is destroyed, such as hydrolysis of water or high temperature environment, the oil film of the leather imitation oil is destroyed, and the oil volatilization is lost, so that the internal fibers of the leather will be bonded together, so that the leather becomes hard and brittle. Therefore, when the inner oil film of the leather is damaged or the oil is lost, the surface between the internal fibers of the leather should be re-injected with high-quality oil that forms the oil film.

Yang Limin took advantage of Wang Hongshan's time to invite Yu Dayou to popularize knowledge to several other people, although he thought that Wu Dawei knew, but others might not understand it so clearly, so it was absolutely necessary for him to talk about it.

Not long after, hearing the footsteps outside, Wang Hongshan walked in with a man in his fifties with short gray hair and wearing a work uniform.