What does 12 mean?

12( 12) is a two-digit natural number between 1 1 and 13, which is an even number. In daily arithmetic units, 12 is also called a dozen.

Writing method

Twelve Chinese characters

Twelve Chinese characters (capital)

? Arabic

Armenian

β Greek (Ionian)

ΔΙΙ? Greece (Attica)

? Hebrew (language)

India (Natural Language)

вi Cyrillic alphabet

? tamil

Roman numerals and Etruscan

Thai

IIX chuvash language

Twelve English

history

The 6th century mural "Twelve Bronze Tables" by Beit Alpha in Israel is the first written code in Roman history.

Japanese Shoto Kutaishi has established the order of the 12th crown.

On 9 February, the former member States of the European Community signed the Treaty on European Union.

Chinese Ancient History

In ancient China, 12-year-old girls were called "the year of golden hairpin".

There are twelve scorpions on the crown of the Emperor of Zhou, that is, jade ropes hanging from his hat. The number of scorpions will decrease according to the rank of the prince.

Twelve chapters of clothing decoration pictures are recorded in Shangshu Yiji, which shows 12 patterns decorated on the emperor's coronation clothes. They are the sun, moon, stars, mountains, dragons and China insects on the clothes (coats), as well as the seaweed, fire, Redmi, horseshoe crab (sound pot) and cricket (sound Buddha) embroidered on the clothes.

Before 22 1, Qin Shi Huang, the ruler of the Qin Dynasty, ordered the collection of state weapons, destroyed them and cast them into "Twelve Golden Men (or Twelve Bronze Men)"

According to The History of Song Dynasty Volume 365 Biography of Yue Fei, Qin Gui of Song Dynasty awarded 12 gold medals in one day, and recalled Yue Fei who fought against gold to Beijing.

technology

There are 12 function keys (F 1, F2, F3, F4, F5, F6, F7, F8, F9, F 10, F 1 2) on the computer keyboard.

A standard digital telephone has 12 dialing keys (1, 2, 3, 4, 5, 6, 7, 8, 9, 0, *, #).

The ASCII code and Unicode code of the computer page-changing key are 12.

The most common voltage on cars, batteries and many weak current devices is 12 volts.

In the early Warring States period, the 12th Canal of Zhangyin was the large-scale water diversion irrigation system in China.

Literature and art

Music and drama 12 semitone on the piano keyboard

According to legend, the twelve-tone melody is the theory of spirit, a music official of the Yellow Emperor. He used the principle that the length of bamboo tube leads to different pronunciations and formulated the rules of melody.

The law of twelve averages invented by Zhu Zaiyu in Ming Dynasty.

The octave consists of 12 semitones.

Twelve-tone technique or twelve-tone system is a kind of scale.

Twelve-tone music, one of the schools of modern music.

Muqam is a traditional classical divertimento composed of songs, dances and music, which is popular in Xinjiang Uygur area of China. There are 12 sets.

In the mid-Qing Dynasty, Kunshan accent and foot color were the "twelve feet color" in the commercial system.

Weights and Measures In daily life, 12 is a common unit for counting or packaging goods, called a dozen. Eggs, refills, egg tarts, etc. Usually bought by the dozen. According to Modern Chinese Dictionary, 12 is called Luo Yi, but this title is rare.

In the prefix of the international system of units, 10 12 is called the legal unit of measurement in People's Republic of China (PRC) (China); According to the name, definition and code of the legal unit of measurement and its multiples and fractions published by the Ministry of Economic Affairs of the Republic of China, it is called Zhao (English code T). 10- 12 is called pi (English code p).

In English units, the length of 1 foot is equal to 12 inch.

In the unit of weight used in China from the Warring States Period to the Sui Dynasty, twelve baht is equal to half two.

In the gold balance system used for precious metal trading (and the drug balance system used for weighing drugs), 65,438+02 troy ounces (drug balance ounces) is equal to 65,438+0 troy pounds (drug balance pounds) (this is different from 65,438+0 pounds in general English units (constant scales)).

Before the monetary system reform in Britain, 65,438 shillings was equal to 65,438 pence.

The highest Beaufort scale for measuring wind force is 12, which is called hurricane.

The maximum intensity of Macquarie earthquake, which measures the degree of damage caused by earthquake to the ground, is 12 degrees.

Mathematical attribute

algebra

The factors of the sixth composite number are: 1, 2, 3, 4, 6, 12.

Fifth highest composite number

Pell number

The first residue

The sum of the Pythagorean numbers of the first group (the circumference of the Egyptian triangle: 3:4:5)

The third pentagonal number and tangible number

The fourth Pronik number

The smallest number n is equal to n and n! Can be expressed as the product of multiple prime factorials (12 = 2! 3! ; 12! = 2! 3! 1 1! )

Unique numbers make n 1, n/2 1 and n/3 1 all prime numbers.

The third super factorial is the product of the first three factorials.

The cardinal number of decimal notation. Decimal system is considered to be relatively simple in expressing shares with decimals, but it is not used in daily life calculation.

In the notation based on 13 or more numbers (such as hexadecimal, etc.). ), 12 is marked with the Latin letter C.

The factor of the sum of any pair of twin prime numbers (except the first pair).

The number of positive factors of 12 (6) is a perfect number, and the sum of all its positive factors is also a perfect number (1+2+3+4+6+ 12=28). Only two figures of this nature have been found for the time being.

Source: (/s/blog _ 490AFBB60100C8U5.html)-/The meaning of KLOC-0/2 _ Rolling up a thousand layers of snow _ Sina blog

geometry

A regular dodecahedron composed of regular pentagons.

A polygon with 12 sides is called a dodecagon.

A polyhedron with 12 faces is called a dodecahedron, in which the regular dodecahedron is one of the five regular polyhedrons.

12 is the number of kisses in three-dimensional space.

In the problem of ball installation in three-dimensional Euclidean space, if the unit ball is tangent to the unit ball, 12 balls can be put in (Kepler conjecture).

In polyhedron, 12 is the number of edges of cubes and octahedrons, and also the number of vertices of icosahedron, truncated semi-cube and truncated tetrahedron.

natural science

The position of magnesium in the periodic table of elements is 12.

The atomic number of magnesium is 12.

Chemistry has dodecanedioic acid (DDAD).

The unit mole used to calculate the amount of a substance is defined as the number of atoms contained in 12g carbon12.

Including antiparticles, there are 12 leptons.

There are 12 quarks including antiparticles.

There are 12 kinds of bosons, including photons, 3 kinds of weakly interacting medium particles and 8 kinds of gluons.

Messier objects M 12 in Ophiuchus is a globular cluster of magnitude 8.0.

NGC 12 located in Pisces is a spiral nebula with the magnitude of 13 438+0.

Time and calendar

12 hour wall clock

The period of the earth's revolution around the sun is about 12 times that of the moon's period of revolution around the earth, so the number 12 is of special significance to human timing and calendar.

In order to mark the position of the sun on the ecliptic every month, the Babylonians divided the sky that the sun passed through every month into 12 constellations, namely the zodiac, and the 12 constellation of the zodiac (namely 12 constellation) was Pisces. In ancient China, the Chinese zodiac on Sunday was divided into twelve days and twelve times.

In ancient China, there were 12 earthly branches to record the time and sequence, and the sea rank was 12. 10 daily trunk distribution and 12 underground branch recycling are an ancient calendar year method in China, with 60 years as a cycle. Each earthly branch with 12 animals becomes the zodiac, and 12 zodiac is a pig. 1 year is divided into 24 solar terms with 12 earthly branches. The time of day is also represented by local branches, so there are 12 hours in a day from midnight, which is equivalent to 23:00 the day before and 0 1:00 the day before.

The modern international calendar divides 1 year into 12 months. 12 months are different in length, but they all have 12 days. They are 65438+ 10/2, February 12, March 12, April 12, May 12 and June 12 respectively.

1 day is divided into 24 hours, with 12 hours in the morning and afternoon respectively. In a day, the hour hand of the clock will turn on the dial twice, divided by 12 hours. The minute hand length is slightly equal to 1.5 times of the hour hand, and the running speed is 12 times of the hour hand.

In addition, in terms of calendar years, humans have recorded BC 12, AD 12, BC 12 and AD 12.

Religion and myth

Leonardo da Vinci's The Last Supper

In Greek mythology,

The twelve gods who entered the Pantheon were called "Twelve Olympians". There are actually 65,438+04 gods who enjoy this honor because the twelve gods in different periods contain different gods.

Legend has it that 12 titans once ruled the world. They are children of Uranus and Gaia, the goddess of the earth.

Hercules, one of the greatest heroes in Greek mythology, made 12 Xiang Ying.

According to the British legend about King Arthur, he had 12 knights of the Round Table.

In Christianity,

The 12 disciples of Jesus are called the twelve disciples of Jesus.

According to Genesis 49.28, Jacob's 12 sons founded Israel.

Traditionally, the 12 night after Christmas is the eve of Epiphany (also known as the twelfth night), that is, the 65438th+1October 5th in the Gregorian calendar; 65438+10.6 is called the appearance day (also called the first 12 day).

The 12 National Day is a very important Christian festival in the Orthodox Church.

In the traditional Jewish custom, a girl should hold an adult ceremony at the age of 12.

In Buddhism,

The explanation of reincarnation is called the theory of twelve causes.

Twelve places is a common name in Buddhism.

There are also some names of 12 gods in Buddhism. For example, the pharmacist Buddha has twelve dharma gods, and there are also 65,438+02 dharma gods called twelve days.

Twelve doctrines are Buddhist classics, and their contents are divided into twelve doctrines to explain the concept of emptiness of Mahayana.

Buddhism divides Sanzang into twelve categories according to genre and content, which are called Twelve Schools or Twelve Classics.

A branch of Shia Islam is called the Twelve Imams.

Three-hole and twelve-classification, four auxiliary classifications in Taoist classics classification

In Manichaeism, there are twelve names of King Bao Guang who live there forever.

Medical treatment and sanitation

Most people have 12 pairs of ribs.

Physiologically, most people have 12 pairs of ribs. The initial segment of the small intestine from the pylorus of the stomach is called duodenum. The related diseases are duodenitis and duodenal ulcer, and the parasite is duodenal worm. This operation is called duodenectomy.

According to the meridian theory of traditional Chinese medicine, the human body has twelve meridians. The twelve meridians, which originates from the elbows and knees of the limbs and follows the branches of the chest, abdomen and head, is called the twelve meridians; The area of the whole body muscle divided by the twelve meridians circulation distribution is called the twelve meridians; The twelve meridians's important acupoints near the wrist and ankle joints are called Twelve Original Acupoints. The skin area on the body surface divided by the twelve meridians circulation distribution is called twelve skins; There are 12 specific acupoints in the chest and abdomen where the qi of zang-fu organs gathers.

Vitamin B 12 is an essential vitamin for human body, which is mainly absorbed by animals. Lack of vitamin B12 can lead to anemia.

Other fields

EU flag

L (lowercase "l") is the 12 letter of the Latin alphabet.

Lamed is the letter 12 in the Hebrew alphabet.

The EU flag consists of 12 Venus arranged in a circle, representing 12 countries that founded the EU.

In football, the penalty is 0/2 yards from the goal/kloc-.

According to international law, the territorial sea of each country is outside the land 12 nautical mile.

Is the twelfth of the sixty-four hexagrams in Zhouyi a hexagram?

There are 12 jurors in Britain and America.

A calendar note in the yellow calendar is called twelve values.

China's Traditional Self-massage Method-Twelve Brocades

K- 12 is the abbreviation of school grades in the United States and Canada.

Twelve peaks in Wushan are located in the Three Gorges of the Yangtze River.

12 years old is the age limit for children and adolescents.

The Number of "12" in the Book of Changes "Gan Kun Pu"

1 .12 Yao Taiji Map

2. There are six hexagrams in Gangua and six hexagrams in Kungua, which is "12".

3. Bagua has a total of 12 yang and 12 yin.

People have 12 pairs of cranial nerves.

5. People have 12 thoracic vertebrae.

6. People have 12 pairs of thoracic nerves.

7. People have 12 organs,

8. People have 12 upper limbs.

9. People have 12 pairs of lower limbs.

10. Whole body 12 general resuscitation (left eye, right eye, left ear, right nostril, right nostril, mouth, left nipple, right nipple, umbilicus, anterior vagina and posterior vagina)

1 1. There are 12 stone pillars in the Great Hall of the People. In 2005, there were 12 anti-counterfeiting touch lines in RMB.

12. The English number 1- 12 is an independent syllable. After 12- 19, add the suffix "Teenager".

The< Gankun Spectrum uses 12 taiji diagram to spread gossip to decrypt the mysterious origin of the number "12".