【Sea River Night Talk】It’s become corrupted! Even passing gas involves principles of chemical engineering!
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From the official WeChat account of the School of Chemical Engineering, Nanjing Tech University ---------------------------------------------------------------------------- In formal occasions, there are always those trivial accidents. What makes them accidents is perhaps the fact that they occur without any warning, catching everyone off guard. Such accidents are either smelly or noisy, and they certainly cause embarrassment for everyone present.
So where do farts come from? When people drink water or eat, they take in some air into their bodies. This air rises to the mouth and is expelled in the form of hiccups (it turns out that hiccups and farts are related). . . . (Rumbling thoughts), it moves down to the intestines, where small bubbles merge into larger ones; eventually it reaches the rectum. As pressure increases, the anal sphincter trembles, and with a ‘pfft’, it is expelled from the body – that’s flatulence.
Next, let’s take a look at the specific composition of farts. The main gases are CO2, H2, and CH4, but all three of them are colorless and odorless. CO2 is produced due to the fermentation of starch. Gases with distinct odors mainly come from H2S, indole, and 3-methylindole (skatole), which are produced by gut bacteria breaking down proteins. Since the only amino acids in the human body that can produce H2S are Cys and Met, the amount produced is small, but it has a very strong odor. Of course, although we are meat-eaters, in our daily diet, rice and noodles definitely make up a larger portion than meat.
Loudness: Loudness is related to the force of the airflow; the greater the force, the larger the amplitude, and thus the louder the sound produced. When the large intestine is filled with gas, it generates air currents with considerable force. The brain is often able to anticipate this situation (that is, it recognizes that it is gas pressure rather than solid pressure), and as a result it controls the relaxation of the anus; this leads to vibrations caused by the flow of air, resulting in what is known as a \"fart with sound\". (Note: Due to a flaw in human evolution, this predictive function is unable to effectively distinguish between liquid pressure and gas pressure, which are both pressures that are distributed relatively evenly; therefore, one must be cautious when passing gas during diarrhea.) ）
When the space for residual gas is small (as it is filled with solid material), the airflow is weak, but since more solid material must be passed through, the gas concentration increases, resulting in a stronger odor. On the other hand, solid substances exert greater pressure on the walls of the large intestine, causing the anus to contract intentionally; as a result, no sound is produced, or if a sound is made it is high-pitched (muscle tension leads to a higher vibration frequency). Apart from silent farts, have you noticed that high-pitched farts tend to be smellier and more potent than low-pitched farts?
As a chemical engineer, principles of chemical engineering are an essential skill that allows us to apply the knowledge we have learned. From a fluid dynamics perspective, flatulence can be analyzed as turbulence; the flow is not stable in a laminar state, and by the time it is detected, it has already mixed with air and been diluted. While silent farts are laminar in flow, with stable movement; they mix much less with air compared to turbulent flows, so the foul-smelling gases...
I’ve learned some knowledge....... Thank you. Eating sweet potatoes, radishes, soybeans, and various vegetables causes a lot of flatulence, but eating meat doesn’t have that effect; eating one pound of beef can result in no flatulence for three days. :lol
What does the saying \"A loud fart isn’t smelly, and a smelly fart isn’t loud\" mean?
The painting style has changed drastically. . . :lol