Amazing knowledge

Chapter 1 The Big Bang Theory: The Truth Is Unbearable
* Staring at a beautiful woman for 10 minutes is equivalent to doing 30 minutes of aerobic exercise, is it true?
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A study from the "New England Journal of Medicine" made many men excited, because the study showed that staring at a beautiful woman for 10 minutes is equivalent to doing 30 minutes of aerobic exercise!Is this day's big good thing real?
British researchers selected 200 men and completed the study over a period of 5 years.They found that men who stare at beautiful women every day can prolong their lives. These men have lower blood pressure and slower pulse rate than ordinary people. They have a lower risk of heart disease, so they can live 3 to 5 years longer than ordinary people.

Studies have also shown that a beautiful woman is like a wonderful landscape painting. When a man stares at a beautiful woman, he will experience symptoms such as blushing, heartbeat, and cold limbs. The secretion will also be accelerated accordingly, and the adrenaline hormone will promote the expansion of blood vessels and improve the blood supply to the heart.If you can gaze at a beautiful woman every day, your brain will generate beautiful emotional memories and maintain the stability of your emotional center, which can greatly reduce the probability of a man's stroke and heart attack.

But how feasible and credible is this claim?Leaving aside the fact that there are any beautiful women who can make a man stare intently for 10 minutes, even if there is, this statement is not reliable.

Because the impact of people's active activities cannot be replaced by passive alternative activities. Simply put, adrenaline can be produced by exercise or by gazing at beautiful women.But the adrenaline produced by exercise can help us get fit, while the adrenaline produced by gazing at beautiful women does not.We usually watch horror movies and play some novel and exciting games, which will also accelerate the secretion of our adrenaline hormones, but can these also be equivalent to aerobic exercise and help us prolong life?
The final word: Instead of pinning your health hopes on gazing at beautiful women, it is better to exercise for half an hour.Even if you don't like sports, spending 10 minutes to let yourself go can relieve the pressure of life and add points to your health.

*Is it true that canned drinks cannot be drunk directly into the mouth?

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Canned beverages cannot be drunk directly to the mouth, otherwise it may be fatal in serious cases. Is it true that small cans are still so lethal?

Because of its compactness and convenience, canned beverages have always been a favorite of many people, but a news of "rat peeing to death" made everyone discouraged from canned beverages.The person involved in the news was infected with the virus in the rat urine left on the can because he drank the canned drink directly into his mouth, and died in the end.Many people believed this news to be true, but it was an out-and-out fake news.

The virus mentioned in the news is leptospirosis virus, which is easy to multiply in sewage, but the probability of this virus spreading through the digestive tract is very small, and the probability of spreading it through cans is almost zero.

However, this does not mean that the most suitable way to drink canned beverages is to drink them with your mouth.Before the canned beverage reaches our hands, it may have experienced countless warehouse turnover and countless people's touch. There are many dusts, microorganisms, etc. on the surface, which are potential sources of pollution.

Columbia University has done related research, they said: the bacteria on the cans are no less than the bacteria on the public toilet toilet.Although the news of "death by rat urine" is a rumor, it does not rule out the possibility.

Furthermore, the fonts on the body of canned beverages are generally printed with colored inks, which contain a large amount of inedible substances, such as pigments and rubber materials. The mouth of the cans is likely to be contaminated with these substances. It enters the body through the mouth.

The survey shows that more than 90% of people will choose to drink canned beverages directly to their mouths without cleaning. This undoubtedly poses a great health and safety risk and is likely to cause various diseases.

The final word: Canned beverages are not incapable of drinking directly into the mouth, but cans are easily contaminated with various bacteria during storage and transportation, which is likely to endanger people's health.Therefore, it is best to use straws or cups when drinking canned beverages. At the very least, you must clean the mouth of the can before drinking it with your mouth.

* Do new phones have to be charged for 8 hours?
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We all have such a deep-rooted idea in our minds that a newly bought mobile phone must be charged for 8 hours, so as to improve the battery life. Does the new mobile phone have to go through such a life?

The claim of charging a new phone for 8 hours to "activate the phone" is real because batteries have a "memory effect" where they remember the "charge capacity" of the battery and if the battery is not completely drained Charging the battery in seconds will most likely overcharge the battery.

Over time, crystals will grow on the battery, and these crystals will hinder the contact between the electrode plate and the electrolyte, resulting in a decrease in the voltage of the battery. In layman's terms, the "storage capacity" of the battery is reduced.

However, this was only the case with early NiMH and NiCd batteries, and simply doing a "full" charge and discharge at regular intervals can fix the problem.

Now, the rechargeable batteries equipped in mobile phones on the market are basically lithium-ion batteries with better performance. Lithium-ion batteries are more compact and exquisite, and can store more energy. The initialization of the battery has been completed.

Therefore, there is no "memory effect" in the lithium-ion battery, and the durability of the battery will not be affected by "charging for 8 hours".

The final word: Today's electronic devices basically have the function of "automatically power off after full power". You don't need to worry about "overcharging". Charging a new mobile phone for 8 hours will not have any impact on the battery life, but Occasionally completing a complete charge and discharge can calibrate the power display inside the phone.

* How to distinguish between men and women from the ID number?
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From a simple ID number, you can tell whether you are a man or a woman. There is so much information hidden in this long string of numbers. Let us find out!
In today's society, there are some girls who are sunny and handsome, and dress as freely as boys, and even some girls call themselves "female men".There are also some boys who prefer women's clothing, and those who speak softly are much quieter than some carefree girls.However, no matter how you dress up, the gender information on the ID card cannot be faked. Even if you can't see the ID card, you can still tell the difference between men and women with the ID number.

Nowadays, our ID numbers are generally 18 digits. This large string of numbers seems to have no rules, but in fact there are many tricks in it!
First of all, everyone should know the birthday numbers.That's right, the 7th to 14th digits of the ID card are the date of birth we are familiar with, and the 6 digits in front of the date of birth are the area code of the place where we apply for the ID card. The 2 digits represent the provincial, municipal and County code.

The code that can help us distinguish between men and women is in the last 4 digits. To be precise, the penultimate digit is the key to distinguish between men and women. Even numbers represent women, and odd numbers are assigned to men.The first three digits of the last four codes are sequential codes. From these digits, we can see which number we are on the day of applying for the ID card. For men, No.4 is 001, and for women, No.1 is 1. .

As for the last digit of the ID number, it is called the "check digit" and has no specific connection with our personal information. This digit is the remainder of dividing the sum of the first 17 digits of the ID number by 11.Some people's ID numbers look special because their last digit is not a number, but an X. In fact, this is because the result of taking the remainder of 17 after summing the first 11 digits of their ID numbers is 10, so Represented by X.

The final word: the small ID card is one of our most important documents, and the ID number is also very particular. The most basic information of each of us is included in this string of numbers. It is our "identity" symbol.

*Is it true that hair dryers emit more radiation than X-rays?

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There is radiation with a hair dryer!The radiation intensity of the hair dryer is greater than that of X-rays!After hearing this news, it is estimated that many beauties with fluttering hair will start to worry. Is the hair dryer really so scary?

First of all, we all know that the electrical appliances in the home, as long as they are powered on, the voltage difference between the two ends of the electrical appliances will inevitably form a small electric field.When current flows through an electrical appliance, an electromagnetic field is naturally generated and radiated outward.As long as it is an electrical appliance that is powered on, there will be more or less radiation.

Although the hair dryer is small in size, its electromagnetic field strength is relatively strong, because the working power of the hair dryer is relatively large, and even the refrigerator cannot compare with it.The magnetic field strength radiated by a hair dryer with a power of 1000W is equivalent to that of a working microwave oven.The hair dryer has such a high radiation intensity, is its radiation intensity really stronger than X-rays?
In fact, there is a misunderstanding here.Although both hair dryers and X-rays are radiation, there are still big differences between the two. X-ray radiation is ionizing radiation, which is of the same nature as nuclear radiation. It can directly cut off the molecular bonds inside human cells and cause great damage to the human body.

But the radiation of the hair dryer is different, it belongs to non-ionizing radiation, and it is still low frequency.Radiation from radio-frequency electromagnetic fields like those from cell phones and microwave ovens speeds up the movement inside molecules, which is how microwaves heat food.

However, the low-frequency electromagnetic field does not even have the function of heating. Its only threat is that it will stimulate the muscles and nerves of the human body to a certain extent, but this requires the strength of the electromagnetic field itself to reach a certain level. Far below the safety value formulated by the International Commission on Non-Ionizing Radiation Protection.

It is one-sided to judge the radiation intensity only based on the radiation value, and it is more objective to compare it with the corresponding radiation safety value at the same time.

The final word: The radiation of the hair dryer and the radiation of X-rays are not in the same nature at all. The radiation value of the hair dryer is completely within the safe value range, and there is no major threat to the human body. It can be used with confidence. "The radiation of the hair dryer Stronger than X-rays" is completely alarmist.

* Are cosmetics flammable?
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Girls are born to love beauty, and cosmetics seem to add a lot of points to girls.But a video on the Internet made people feel flustered. In the video, a woman lit half of her face directly when she lit a cigarette, and her right cheek was burned by flames.Netizens believe that the cosmetics used by women caused the accident. Are cosmetics really so easy to burn?

If cosmetics are flammable, the main reason should be the ethanol contained in cosmetics.Ethanol, or alcohol, is a veritable flammable substance.Adding alcohol to cosmetics seems to be a customary thing. If you pick up a liquid cosmetic in a shopping mall and look at the ingredient list behind it, nine out of ten it will contain ethanol.

It is estimated that someone will ask: This ethanol is ignited immediately, it is a very flammable thing, why is it added to cosmetics?In fact, this has a lot to do with the nature of alcohol. Alcohol is a very friendly solvent. Many substances can be perfectly integrated with alcohol. Alcohol actually plays a role in cleaning, disinfecting and dissolving essence.

These things are organic solvents and are flammable.However, the content of alcohol added in cosmetics is not much, at least its content will not ignite the face, and we will use lotion, cream and other things for follow-up maintenance after using toner. Alcohol is a very volatile substance. After it is applied to the face, it will evaporate quickly, and as the concentration of alcohol drops, the possibility of being ignited is very small.

In addition to alcohol, a water-soluble solvent, some cosmetics add fat-soluble solvents, similar to various esters.

Adding these organic solvents in cosmetics is to dissolve essences and other substances; the second is to make them volatilize faster, especially for perfumes. If safe and non-flammable water is used as a solvent, the volatilization speed is slow and it is difficult to achieve the effect of perfumes.At the same time, alcohol also has a cleaning effect, and adding it to skin water is also beneficial to the skin. Of course, people with sensitive skin should try not to choose cosmetics containing alcohol, after all, alcohol has certain irritation.

The final word: Some cosmetics do contain flammable alcohol, but at levels of a few parts per thousand it's perfectly safe.Of course, burning the face is an occasional event, but for the sake of safety, try to avoid contact with open flames when using cosmetics, especially when using toilet water, perfume and other items with high alcohol content.

*Can wearing crystals cure diseases?
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In the gem market, there are always various sayings, such as turquoise can keep you safe, tourmaline can protect you from radiation, and crystals can help us heal our minor ailments and prolong life. Crystals really have such great capabilities. ?

If crystals can cure diseases, then every family can buy a good crystal to see the nursing home. Why do we need hospitals and doctors?In fact, if you think about it, you will know that it is just a gimmick of the merchants. Whether it is crystals or other rare and precious minerals, almost all of them cannot cure diseases, and they do not help health in any practical sense.

Crystals are a kind of minerals. Minerals are actually inorganic compounds. As for whether they have an "energy field", it is difficult to draw a conclusion, but they certainly do not have the "energy field that can cure diseases".

There are also some radioactive minerals, but there is no evidence that their effects on the human body are beneficial, and common gemstones such as crystals and tourmalines that we often see are basically non-radioactive.It is really not very possible to protect one's health by wearing gemstones such as crystals.

Although minerals cannot contribute to our health by wearing them around, they shine in medical treatment.The most common one is plaster crystals. When fractures occur, plaster is used to fix the wound and help the bone heal better.There is also barite, which you may not be familiar with, but barite is actually the main "ingredient" of "barium meal", and "barium meal" is indispensable for gastrointestinal radiography.

There are also various crystals that play a very important role in medical treatment. Although wearing gemstones cannot cure diseases, they also protect our health in other fields.

The final word: Common gemstones do not have health benefits, and their health benefits are just everyone's good wishes.The beauty of these gemstones is beautiful, you can decorate yourself as an ornament, don't pin your hope of prolonging life on them.

*Toothpaste does not stick to water is the correct way to brush your teeth, is it true?
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People brush their teeth in nothing more than two ways: one is to start brushing teeth directly after squeezing out toothpaste; the other is to moisten toothpaste in water and then brush teeth.Which one is the correct way to brush your teeth, is it right not to get wet?
The instruction manual of the toothpaste only says "brush your teeth twice a day, and squeeze out about 2 cm of toothpaste each time", and it doesn't mention whether to get water or not.In fact, we use toothpaste for only one purpose: to clean the mouth and teeth.And this purpose is achieved through the friction between the toothbrush and the teeth, in which the toothpaste plays the role of an abrasive.

However, toothpaste also contains a certain amount of surfactants and foaming agents. Their function is to assist in cleaning. It is precisely because of their existence that we will produce foam when we brush our teeth.But these things have a characteristic, that is, they must be dissolved and work in a water environment.In this way, do you have to get water on the toothpaste when brushing your teeth?
In fact, it is not the case. Even if you do not touch water when brushing your teeth, you can completely clean your mouth.The saliva secreted by an adult's mouth is as high as 1.5L a day. Don't believe this fact. We swallow so much saliva every day, and if toothpaste is put into the mouth, the mouth will release more saliva due to the stimulation of the toothpaste. These Sufficient to dissolve foaming agent and surfactant ingredients in toothpaste.

So no matter whether you get wet or not, as long as you brush your teeth in the mouth, it is equivalent to getting wet, which is just the difference between clear water and saliva.However, there is a disadvantage of dipping in water, that is, the toothpaste is very easy to fall off, so the best way is to rinse your mouth before brushing your teeth, and then "dry brush".

The final word: No matter whether the toothpaste is stained with water or not, it has no substantial impact on the cleaning effect of brushing teeth. You don't need to change your brushing habits for this, just let nature take its course.

* Home cooking exacerbates PM2.5, is it true?
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"Chinese people's cooking is also a major reason for the increase in PM2.5." A sentence from the director of the Beijing Foreign Affairs Office exploded across the country. Cooking a meal can also aggravate air pollution, so can this meal still be cooked in the future? ?
In fact, cooking fume is indeed a source of PM2.5. However, cooking fume only accounts for a few percent of PM2.5, which is insignificant compared with the exhaust gas emitted by motor vehicles. Industrial enterprises The main sources of PM2.5 are exhaust gas, motor vehicle exhaust and dust.

There are eight major cuisines in our country, frying and cooking, among which the PM2.5 is basically stir-frying and deep-frying, because when cooking oil is cooked at high temperature, more oily smoke will be produced, if you do not use a range hood or If the exhaust fan is used, the oil fume will be directly discharged into the air, which will affect the air quality.However, with the popularity of range hoods, the "contribution" of cooking fumes to PM2.5 is very small, and even if there is an impact, it is only partial.Looking at the overall situation, PM2.5 really can't make any waves at this point.

On the contrary, some large-scale catering, such as canteens or catering companies, and some self-operated catering shops, they take cooking as their main business, and the oily fume produced will inevitably be much more than that of ordinary households. If these places are not properly prepared in time Smoke exhaust work, let the oil fume into the air, the air quality will inevitably be affected to a certain extent, but ordinary families do not have to worry so much about three meals a day.

Three meals a day is our living habit, "Food is the most important thing for the people", we don't have to give up the original way of life just to avoid PM2.5.

The final word: home cooking does produce PM2.5, but the content is very small, and the air itself has self-purification ability, which can completely digest the PM2.5 produced by home cooking. The family's three meals a day will not affect the air quality.

*Is it true that pulling out wisdom teeth can slim your face?

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The appearance of many celebrities is not only not affected by the years, but is getting higher and higher. Although superb makeup techniques can add a lot of color, it is impossible to turn a pie face into an awl face with makeup alone!However, many celebrities claim that their faces became smaller after their wisdom teeth were pulled out. Is this possible?
In fact, the face we often say can only be regarded as a piece of skin. The bones and muscles of the face make up our face shape, and the face skin is just the skin covering the bones and muscles.The bones of the face are roughly divided into the cheekbone, the maxilla and the mandible, and these three parts support our entire face.

The cheekbones are the widest part of the face, located below the eyes, and define the upper contour of the face.The lower contour of the face is basically determined by the mandible and the masseter muscle, which attaches to the angle of the mandible.If the masseter muscle is developed or the mandibular angle is wide, it is likely to give people the visual experience of "a wide face".Therefore, in order to pursue a more refined face shape, many people choose to seek help from plastic surgeons to amputate part of their mandible or perform proper polishing to modify their face shape.

As for saying that pulling out wisdom teeth can slim your face, there is actually no medical basis, because the position of wisdom teeth is inside the upper and lower jaws. Neither grows on the outside of the jawbone.It is not the wisdom teeth that determine the width of the lower face, but the mandible and masseter muscles, so even if the wisdom teeth are pulled out, it will have no effect on the shape of the face.

The final word: From the day we were born, our face shape has been determined. Unless we use a knife to grind our bones, our face shape will not change. Those who want to slim their face through wisdom teeth extraction should give up this idea.

*The distance traveled by each person in a lifetime is equivalent to 4 circles around the earth. Is it true?

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People walk all their lives. From the moment we learn to walk, we walk with our legs every day.Some people say that each person can go around the earth 4 times in a lifetime. Can we really walk that much in a lifetime?
First of all, there is a big loophole in this sentence itself. "Everyone" itself is unrealistic. There are many athletes all over the world, especially runners and race walkers. Running, the road they have traveled in their life is much more than ordinary people don't know.

From a scientific point of view, the longest circumference of the earth is the equator, and the circumference of the equator is 40075.7 kilometers.The normal walking speed of ordinary people is 5 kilometers per hour. If we want to circle the earth 4 times, assuming that the total time we walk every day is two hours, then the distance we walk every day is 10 kilometers, even if it is In this way, it will take a full 50 years to be able to "circle the earth 4 times".

But the reality is that with the popularization and development of transportation, we travel in a variety of ways. Private cars and public transportation are our first choice. When we really need to walk, we rarely want to walk every day. 10 kilometers is a bit unrealistic.

However, if the daily walking distance is less than 10 kilometers, then if we want to complete the goal of "circling the earth 4 times", we have to continue to walk longer. Calculated in this way, we don't know how long it will take to achieve this goal.

The final word: the distance traveled by each person depends on their own lifestyle and living habits, and it cannot be generalized. Some people can only circle the earth two or three times in their lifetime, but some people may circle the earth seven or eight times. Everyone Everyone has their own life and their own path, which cannot be summed up in one sentence.

*A piece of paper can only be folded in half at most 7 times, is it true?

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Origami seems to have no technical content. Children as young as 3 years old can make origami, but it is said that a piece of paper can only be folded in half at most 7 times. Origami is obviously very simple, why can it only be folded in half 7 times?

In fact, the saying that a piece of paper can only be folded 7 times is very old, and it is so old that some people have broken this "common sense".As early as 2002, a female middle school student named Britney Gallivan overturned this statement with practical actions. She did not use our common A4 paper, but thin toilet paper. She folded the paper 12 times, successfully created a new world record.

This record has been maintained for 10 years. It was not until 2012 that the students of St. Mark's Middle School in Texas broke this record again. They successfully folded a piece of paper almost 4 kilometers long in half 13 times, setting a new record. A new record was set, but unfortunately, Guinness does not recognize the event.

However, we already know from these that a piece of paper can be folded in half more than 7 times, but why is it so difficult to fold paper in half?In fact, this is the power of the index.

Every time you fold it in half, the area of ​​the paper will become half of its original size and its thickness will double. This figure may not seem like a big deal, but the exponential growth is very rapid.For example, after the paper is folded in half 2 times, the thickness will become 10 times of the original, and the area will become 1024/1 of the original.Just by folding it 1024 times, the effect has reached more than 10 times. It can be seen that "folding in half" is really not an easy task.

The final word: How many times a piece of paper can be folded in half depends on the size and thickness of the paper. If you think about it divergently, as long as the thickness of the paper is small enough and the area is large enough, it is possible to fold it in half infinitely.

* Is laser correction of myopia reliable?

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Whether it is a boy or a girl, as long as they are experienced myopia, they should be afraid of glasses like the bottom of the wine bottle. However, laser correction surgery in medicine has saved many people who are troubled by the "bottom of the wine bottle". Is it really reliable?

Laser correction of myopia surgery was originally called Lasik surgery, that is, excimer laser in situ keratomileusis. The Lasik procedure uses a laser to cut a flap in the cornea, thereby adjusting the curvature of the corneal stroma, thereby improving the patient's vision.

From the first Lasik surgery in my country in 1997 to the present, in just over ten years, Lasik has been enthusiastically sought after all over the country. Thousands of myopia patients want to completely stay away from glasses through this surgery.

But this operation has certain risks, because the thickness of the cornea is different for each of us, and the degree of myopia is also different.If the cornea is normal, it can fully withstand the pressure on the cornea inside the eye, but if the cornea is cut because of Lasik surgery, once the corneal tissue is injured, it is very likely that it will not be able to continue to resist the intraocular pressure from the eye , and the deeper the degree of myopia, the greater the damage to the corneal tissue caused by Lasik surgery.

When the corneal tissue cannot withstand the intraocular pressure, the corneal tissue that has become a "concave lens" due to surgery will gradually become sharper under pressure, and the worst result is to become keratoconus.In the eyes of ophthalmologists, keratoconus is an incurable disease. Unless a corneal transplant is performed, the only consequence is blindness.

Although keratoconus is the worst sequelae of Lasik surgery, there are many other complications with a relatively high incidence of Lasik surgery, such as glare, regression of vision, double vision, eyeball hyperemia, and so on.

The final word: Lasik surgery is indeed a shortcut to regain good vision, but this method also has great risks.Before deciding to undergo this surgery, be sure to carefully weigh the pros and cons.

(End of this chapter)