How many gases are there in the atmosphere? Which is the heaviest and which is the lightest? The material composition of the atmosphere. The atmosphere on the earth contains constant gas components such as nitrogen, oxygen and argon, gas components such as carbon dioxide and nitrous oxide, and gas components such as water vapor, carbon monoxide, sulfur dioxide and ozone that vary greatly. Among them, solid and liquid aerosol particles such as dust, smoke particles, salt particles, water droplets, ice crystals, pollen, spores and bacteria are often suspended. The specific components are nitrogen (78.084), oxygen (20.946), argon (0.934), water vapor (0.25), carbon dioxide (0.032), neon (0.00 18), helium (0.00052) and methane (0.0052).
The heaviest gas should be radon in a rare gas with a relative atomic mass of 222.
The lightest gas should be hydrogen in a rare gas with a relative atomic mass of 2.
The layer with the highest ozone content in the atmosphere. Generally, it refers to the atmosphere with a height of 10 ~ 50 km (roughly equivalent to the height of the stratosphere);
It also refers to the atmosphere (ozone layer) with the largest ozone concentration between 20 and 30 kilometers.
How many surnames are there in China (by population)? See your top ranking 100? 1 Li 2 Wang 3 Zhang 4 Liu 5 Chen 6 Yang 7 Zhao 8 Huang 9 Zhou 10 Wu * Shang * Lu 16 Xu 12 Sun 13 Hu 14 Gao 15 Lin/kloc. 9 Ma 202 Cao 33 yuan 34 Deng 35 Xu 36 Fu 37 Shen 38 Zeng 39 Peng 40 Lu 4 1 Su 42 Lu 43 Jiang 44 Cai 45 Jia 46 Ding 47 Wei 48 Xue 49 Ye 50 Yan 5 1 Yu 52 Pan 53 Du 54 Dai 55 Xia 56 Zhong 57 Wang 58 Tian 59 Ren 60 Jiang 6 1 Fan 62. Tan 66 Liao 67 Zou 68 Xiong 69 Jin 70 Lu 7 1 Hao 72 Kong 73 Bai 74 Cui 75 Kang 76 Mao 77 Qiu 78 Qin 79 Jiang 80 Shi 8 1 Gu 82 Hou 83 Shao 84 Meng 85 Long 860,000 87 Duan 88 Cao 89 Qian 90 Tang 9 1 Yin 92 Li 93 Yi 94 Chang 95 Wu 96 99 Gong 100 Wen Experts from Chinese Academy of Sciences Interpret the New Edition of Hundred Family Names. The day before yesterday, the new "Hundred Family Names" funded by the National Natural Science Foundation was released. The reporter interviewed Yuan Yida, a researcher at the Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, who presided over this research topic. He introduced the mystery of China's surname to the reporter. Yuan Yida, a mysterious surname with a hidden genetic code, explained that in China, surnames have been followed by men for a long time, but from a genetic point of view, only men have Y chromosomes, so Y chromosomes are passed along with surnames to male offspring, so people with the same surnames have the same type of Y chromosomes and their genetic genes. "In the survey, we found that many genetic diseases only spread among people with the same surname. Counting the number and distribution of names is very helpful for studying human genetics. " Yuan Yida told reporters. Xuan Ji II's surname is not necessarily the same as that of China people. They always ask their names. If you find that it is the same surname, you will feel very kind. They think they are "a family 500 years ago". "In fact, this is not credible. After our investigation, we found that there may be hundreds of sources for a surname, such as Li, the first surname in China, some from winning and some from winning. Mystery 3: Chinese surnames have the most connotation. Yuan Yida said that surnames are actually an important symbol of cultural inheritance not only in China, but also in the world. However, there is no country in the world whose surname is as complete and connotative as China. Yuan Yida explained, for example, before the Meiji Restoration in Japan, there were only a few surnames. In order to reform, Emperor Meiji asked all the people in the country to have surnames, so in just a few years, more than 80,000 surnames appeared, and most of them were expressed by land names, such as Matsushita, Inoue and Tanaka. Therefore, it is difficult for Japanese scholars to associate Japanese surnames with human inheritance. It is newly discovered that there is a village named "Nan" in Henan. In this survey, many strange surnames were also found, and these surnames have never been recorded. " When I saw them in the past, I thought these strange surnames were caused by a clerical error, but after our investigation, I found that these strange surnames have far-reaching roots. "For example, Yuan Yida told reporters that in Henan, the research group found four small villages with the surname of" Nan ",and all the men, women and children in the villages were surnamed" Nan ". At that time, the research team thought that the surname was caused by a clerical error, which was not statistically significant. However, the Korean cultural department was very surprised after hearing the news, and immediately organized a "root-seeking delegation" to come to China. It turns out that the' Nan' surname is its own root in the eyes of Koreans. "They told me that a stone tablet was unearthed in Henan during the Northern and Southern Dynasties, which recorded the deeds of a Xianbei official. His name is "Nanlou" and his surname "Nan" moved northward with Xianbei. At that time, Songhua River was renamed "Nan Jiang". Subsequently, these Xianbei talents named "Nan" came to today. Therefore, these villagers named' Nan' in Henan are considered by Koreans to have a lot to do with themselves. "Whether the new hundred surnames have scientific and technological content is controversial. Yuan Yida, a researcher who presided over the survey, said that compared with the survey conducted 20 years ago, the sample scope of this survey was larger, involving nearly 40% of counties in China, and almost all of them used China's surname. The survey results get rid of the "priority" of powerful people and are closer to the distribution of surnames in China. In particular, the data and distribution areas of the top 300 common surnames of China people may provide new clues and references for the study of Y chromosome diversity, disease distribution and the origin of Han nationality in China, which has important research and practical value. However, some experts said that without this survey, the new hundred surnames will definitely come out, and it is very simple. A few years after the fifth national census, it is clear at a glance how many surnames there are in the country, the proportion of Zhang, Wang, Li and Zhao, and where they are distributed. It takes scientists two years to investigate something that can be "done" in a few minutes through census data? More importantly, no matter how scientific the investigation in this place is, the results are certainly not as comprehensive and accurate as the comprehensive census data nationwide. For example, this survey obtained 465,438+000 surnames. There are probably more than 4 100 surnames in the national census data. The cost of this survey will not be small. Wouldn't it be better if it were used in more meaningful research? Scientists are precious wealth, but what a waste it is if the work done by scientists in two years is far less comprehensive and accurate than that done by a computer in a few minutes? Public * * * resources can't enjoy * * *, and whoever does it is who's achievements, and the result is bound to be repeated work and a waste of people and money. According to Xiamen Evening News, three surnames are the first surnames: Li Li's surnames come from a wide range, with hundreds. It first comes from the "win" surname. In the Spring and Autumn Period, it was popular to take official positions as surnames. Laozi, the founder of Taoism, took Li as his surname because his ancestors were officials, and later passed it on as "Li". In the early Tang Dynasty, the founding fathers, such as Xu, Tai, An, Du, Hu, Hong, Guo, Ma, Xian Yu, Zhang, Abu, relic, Dong, Luo and Zhu Xie, all gave their surnames to Li, and the population increased greatly, gradually becoming the first surname in China. The second surname: Generally, the descendants of kings are called princes and grandsons, and then they are used as surnames. In addition, many other surnames have been derived, the most of which is "Gui", which is said to come from the ancient emperor Yu Shun. In addition, some people surnamed Wang fought in the Shang and Zhou Dynasties, and even the monarch of Kugaoli was Wang Xing. The third surname: Zhang, according to Yuan He's Compilation: "Qingyang, the fifth son of the Yellow Emperor, was born and lingering, bowing, watching lonely stars, making bows and arrows, and worshiping because of his surname Zhang. "So according to legend, Zhang's surname originated from the Yellow Emperor and is a descendant of the Yellow Emperor. Since the Han Dynasty, Zhang's surname has gradually increased, which is related to the rise and popularity of Taoism at that time. At that time, the saying that "the Yellow Emperor gave Zhang a surname" prevailed, such as Taoist leaders Zhang Jiao and Zhang Lu at that time. A probe into the penultimate surname: Yuan Yida said that this surname was accidentally discovered by the research group in Guoyang County, Anhui Province and Zhangwu County, Liaoning Province, with about 2,000 people. Interestingly, these people have no contact with each other, but they all know the origin of their surnames. They all claim to be direct descendants of Yue Fei. When they were persecuted, they fled here and reversed the word "Yue" to form this new surname. According to Yuan Yida, the surname of "death" is mainly distributed in the northwest of China, which is developed from the four-character compound surname of ethnic minorities in the Northern Wei Dynasty, and the number is decreasing at present. The penultimate surname: Nan (pronounced pronunciation) is distributed in Henan Province and developed from the surname of Xianbei nationality in the Southern and Northern Dynasties. It was originally the name of a bird. At that time, because people admired birds, it became "south", and then moved north, and most of them migrated to the Korean peninsula. China has rarely existed. The latest data shows that there are 4 100 surnames in China * * * Yuan Yida told reporters that in fact, Chinese surnames were investigated as early as 20 years ago, but the sampling rate at that time was very low, only 570,000 people were counted and more than 3,000 surnames were found. " The sampling rate at that time was too low, so the results were not credible. "Yuan Yida's research project has nearly 300 million people, basically covering the whole country." It took our project team two years to find 4 100 surnames and count the number of people. We have also received help from many counties and cities. "Yuan Yida said. The origin of related link surnames was before Qin and Han dynasties, and surnames and surnames were obviously different. Surnames originated from matriarchal society, and the same surname indicates the blood relationship of the same matriarchal family. Most of China's earliest surnames came from his female side, such as Jiang, Yao, Yi, Yi and Ying. It shows that this is a clan group handed down by some different grandmothers. Surnames are produced after surnames, which is the result of determining blood relationship according to paternal line. This is only possible when the patriarchal clan system is established. Therefore, when we read "Huangdi Xuanyuan surname, Ji surname" and "Shanshi Lie surname, Jiang surname", we can understand that the Chinese nation originally belonged to two tribes, or a tribal alliance organized according to matriarchal blood relationship. Hundreds of surnames originated from hundreds of surnames, which have been circulating for the longest time and the widest range in China. It was written and popularized earlier than Saint Amethyst. "Hundred Family Names uses four fonts, and every sentence rhymes, like a four-character poem, which is easy to read and remember, so it has spread to this day and has far-reaching influence. Hundreds of surnames originally collected 4 1 1 surnames, which were later added to 504 surnames, including 444 single surnames and 60 compound surnames. "Hundreds of Family Names", together with "Three" and "Money", became a fixed teaching material in ancient China. In addition to the signature, this edition is contributed by the Evening News. Compared with the list of "100 surnames" in China, Suzhou surnames have an obvious feature, that is, there are more surnames in ancient, Shandong, Shen, Jin, Qian and Yu places, ranking in the forefront; However, the surnames of Li, Liu, Yang, Huang and Lin are relatively backward. Among the top 100 surnames in China, some have been pushed out of the top 100, such as Yu, Wei, Wan, Tian, Jia and Xiong. In addition to common surnames, there are many rare surnames in the data, including head, bone, heart, kidney, intestine, hand and claw belonging to human or animal organs. The names of animals are ducks, pigeons and lambs; There are snow, wind, salt, melon, peach, piano, window, box, chopsticks and gourd belonging to meteorology or articles; There are women, men and sisters-in-law, which can indicate gender; There are foreign and China cymbals indicating directions or place names; There are one, four, five and ten representative figures; Verbs include laughing, rubbing, guessing and picking; The general adjectives are "Xiang" and "Bian" ... These rare surnames have dozens of people at most, and the least is 1. Unexpectedly, "surname" itself has become a surname, and words that are a bit "problematic" to ordinary people, such as sin, tinea, dumb, burial, dirty, bad, and coquettish, are also used as surnames. :2500sz。 /news/SZ 1/2006/ 1/ 13/SZ 1- 16- 14-57-767 . s
How many kinds of Rubik's Cube are there? I'm not exaggerating, there are too many kinds of Rubik's Cube. There are more than 300 kinds of common Rubik's Cube alone!
There are several kinds of table executives in the industry.
Enterprise manager in charge of civil construction supervision.
Astronomers, computer programmers
System analyst and landscape architect
Architect, traffic planner
Chemical engineering technician, civil engineer
Landscape Architect/Surveyor
Sales engineer, industrial engineer
Quality control engineer, ceramic technician
Pharmacist veterinarian
Public health physician traditional Chinese medicine
Nursing Assistant practical nurse
Preschool teachers and special education teachers
Public relations officer of accountant
Lawyer psychological counselor
Social worker, personnel manager
Translation, human intermediary
Librarians, journalists
Editors and screenwriters of newspapers and magazines
Book editor, stone carver
Woodcarving cartoonist
Dancers and instrumentalists
Construction and engineering management, steel structure design and management personnel
Microcomputer communication/electronic magazine editing
Information manager, naive education teacher
Franchise chain store manager marketing project
Telecom engineer web designer
City dispatcher, process engineer
Civil construction machinery operator and electrical engineer
Mechanical draftsman, architectural draftsman
Electronic data processing system operator and photographer.
Merchant ship staff, civil aviation transport drivers
Marine engineer flight controller
Nutritionist eyeglasses expert
Medical records manager insurance assistant
Salespersons and business personnel of securities companies
Sales agent, real estate agent
Purchasing staff, import and export clerk
Futures broker accountant
Commercial art designer interior designer
Announcers and artists
Professional athlete TV presenter
salesman
International Trade English Documents for International Trade Practitioners
Secretary for Chinese typist affairs
Data registrar, assistant accountant
Assistant warehouse manager for quality control
Production planning assistant of distribution personnel
Postal personnel
Customer service management of customs declaration personnel
Bank clerk, financial cashier
Foreign exchange traders, travel agencies
Tour guide, flight attendant
Cultural relic commentator and chef
Bartender, western chef
Babysitting service for catering staff
Beauty barber beautician
Security personnel, police
Firefighter fashion model
Commodity salesman
Pet beautician
Horticultural crop cultivator Nursery worker
gardener
Construction workers, plumbers and electricians
Industrial plumber, industrial wiring worker
Indoor wiring worker general electrician
Design of ceramic tile laying for sanitary pipeline
Wiring worker painter
Automotive sheet metal welding machine
General sheet metal work special welding
Casting metal mold manufacturer
Fitter, auto mechanic
Automobile electrician service machine repairman
Heavy machinery repairman automobile chassis worker
Precision grinder and milling machine
CNC lathe operator refrigeration air conditioning operator
Refrigeration and air conditioning decoration audio-visual electronics workers
Industrial electronics worker baker
Motor repairman
Electronic instrument repairman, jewelry and precious metal manufacturer
Precision measuring tool manufacturer musical instrument Andhadhun
Precision mechanical ceramist
Printers, designers and plate makers.
Bakery and beverage technician
Woodworking furniture
Sewing worker, knitting worker
Suit workers, national costume sewing workers
Shoemakers, fashion designers and manufacturers
Women dress workers
Metal modeling of heat treatment workers
Metal surface treatment worker plywood manufacturer
Cold working planer
Metal electroplating worker, plastic mould worker
Plastic product manufacturer rubber product manufacturer
Paper products manufacturers, photographers, plate makers
Dairy manufacturers and electronic assemblers
Car driver, fishing boat crew
Automatic lathe oil pressure controller
Cleaning service personnel
professional athlete
There are several kinds of atoms. At present, more than 100 elements have been found, but the types of atoms are unknown. Because 1 element will have several atoms, such as C atom, such as C 12, C 13, C 14 and so on.
How many forms does water always have? Morphology and classification of water
(A) the form of water and water cycle
Water exists in nature in three forms: solid, liquid and gas. Specifically, solids include ice, snow, frost and hail; Liquid state includes clouds, rain, fog and dew; The gaseous state is mainly water vapor.
Water cycle refers to the continuous movement of water in nature through various links in hydrosphere, atmosphere, lithosphere and biosphere. There are three forms of water cycle: the cycle between ocean and land (land-sea cycle is a big cycle), the cycle between land and land (inland cycle) and the cycle between ocean and ocean (ocean cycle). Land circulation (large circulation) mainly includes evaporation (water vapor), water vapor transport (clouds and fog), precipitation (rain, dew, snow, frost and hail) and runoff (surface and underground); Inland circulation is mainly: evaporation and plant transpiration, precipitation; Ocean circulation mainly includes evaporation and precipitation. The water cycle is of great significance to the earth, which mainly includes: (1) keeping various water bodies in a state of constant renewal; (2) Maintain the dynamic balance of global water. (3) Promoting the material movement of nature; (4) Connecting the land and the sea; (5) Shaping the surface morphology.
2) Classification of water
Water can be divided into two categories: fresh water and seawater (salt water).
Fresh water mainly refers to fresh water stored in various water bodies (glaciers, surface rivers, lakes and underground aquifers) and fresh water flowing in various water bodies.
The proportion of water in nature is: ocean water accounts for 96.53%, atmospheric water accounts for 0.00 1%, and land water accounts for 3.5%. Therefore, the proportion of fresh water resources available to human beings is very small, and the proportion of fresh water resources that human beings can easily use at present is even smaller, mainly river water, fresh lake water and shallow groundwater. These fresh water reserves only account for 0.3% of all fresh water, accounting for 7/100000 of the global total water, that is, the truly effective utilization of fresh water resources in the world is about 9000 cubic kilometers per year. Icebergs, glaciers, deep groundwater, water in soil and other fresh water account for 99.7%, which is generally difficult for human beings to use. For example, Antarctica, the continent with the richest fresh water resources in the world, covers an area of140,000 square kilometers, and more than 95% of the area is covered with ice and snow all the year round, forming a huge and thick ice sheet with an average thickness of 2,450 meters and a total amount of ice and snow of about 27 million cubic kilometers. It accounts for more than 90% of the global ice and snow, and stores 72% of the global available fresh water. It is estimated that this fresh water can be used by all mankind for 7500 years. But Antarctica is in the sea, and the melting ice water quickly melts into the sea, making it undrinkable for human beings.
People mainly drink pure water, mineral water, mineralized water, space water, oxygen-rich water, deionized water, tap water, distilled water, magnetized water, hard water and so on.
Tap water: it is a substance composed of organic and inorganic substances such as water molecules, microorganisms and minerals. It refers to the fresh water of rivers and lakes treated by coagulation, sedimentation, filtration, disinfection and other water purification processes in water plants, and finally supplied to users by water pumps through water distribution pipelines. Must meet the national sanitary standards for drinking water.
Mineral water: water with minerals exceeding a certain standard. It is natural water and contains many minerals (concentrated solution of 28 trace elements). There are two kinds: one is the spring water flowing from the paleoecology deep in the earth's crust 1000-3000m; The second is the mineral dissolved water flowing from the surface dissolved rocks. The former is the second, third and fourth life-related elements. There are some minerals in the mineral water behind. The connotation of China's national standard for mineral water is the top in the world, which can be said to include almost all the elements related to life, such as II, III, IV, VI and VII. However, in the examination and approval of a mineral water production license, as long as the contents of 2-3 elements such as Ca++, mg++ and Sr ++ are met. In recent years, the mineral water factory has produced a lot of fake mineral water, which is difficult to distinguish between true and false.
Now society likes to drink bottled mineral water. It is generally believed that bottled mineral water is safer or healthier than tap water. Actually, it is not. In fact, bottled water standards in various countries are usually formulated on the basis of tap water hygiene standards. As long as the quality meets the standard, bottled water and tap water are safe for ordinary people. However, people with severely impaired immunity or other specific diseases may be more sensitive to some impurities or microorganisms in water. In order to reduce the risk, you can buy high-purity bottled water or drink tap water after further treatment (such as boiling).
In some areas, there is a tradition of drinking mineral water. People think that water with high content of certain minerals can treat diseases or have health care effects. According to the World Health Organization, although some mineral water can help provide some important micronutrients (such as calcium), there is no convincing evidence that drinking mineral water has a health care function. There is no requirement for the lower limit of micronutrient content in drinking water in the World Health Organization's Guide to Drinking Water Quality.
There are also some bottled water with extremely low mineral content, such as distilled water and purified water. Some people worry that drinking this water for a long time is not good for your health. According to the World Health Organization, many people are used to drinking the same rain with extremely low mineral content, and no obvious adverse effects have been found on their health. The World Health Organization has no scientific information about whether drinking this bottled water regularly is beneficial or harmful.
Some people will also ask whether mineral water contains carcinogens, and the controversial substance is mainly bromate. Natural mineral water actually does not contain bromate, but generally contains bromide. Bottled mineral water is sterilized by ozone in the production process, and ozone will react with bromide to generate bromate. Health Canada's research shows that bottled water disinfected with ozone contains 4.3 ~ 37.3 micrograms of bromate per liter, with an average content of 18 micrograms. Tap water also contains bromate, but the content is low, ranging from 0.55 to 4.42 micrograms per liter, with an average content of 1.7 1 microgram.
Many animal experiments show that mice drinking water containing bromate will grow tumors in kidney, thyroid and peritoneum. The World Health Organization's International Agency for Research on Cancer found that there is enough evidence to prove that bromate can cause cancer in experimental animals, but there is not enough evidence to prove that bromate can also cause cancer in humans, so bromate is listed as a substance that may cause cancer in humans. The United States Environmental Protection Agency and Health Canada also listed bromate as a substance that may cause human cancer.
Bromate was widely used as flour treatment agent before, but because of its carcinogenicity, bromate has been banned in many countries since 1990. China cancelled the use of potassium bromate as a flour treatment agent in wheat flour in 2005. As for the content of bromate in drinking water, the World Health Organization recommends that it should not exceed 10 microgram per liter. According to the results of animal experiments, this value is equivalent to the probability of cancer in a person's life not exceeding one in ten thousand.
Mineralized water: it is a mineral and mineral drink artificially added on the basis of pure water.
Ultra-pure water (often called pure water) is water produced by reverse osmosis technology or supercritical fine technology in order to develop ultra-pure materials in American scientific and technological circles. Water containing no other substances except water molecules.
Oxygen-rich water: It is the medical research water used by the American medical science community to study the anaerobic and aerobic properties of biological cells. Oxygen-rich water means adding more oxygen to pure water.
Deionized water: that is, water passes through cation exchange resin (generally styrene type strongly acidic cation exchange resin), so that cations in water are adsorbed by the resin, and cations H+ on the resin are replaced by water, forming corresponding inorganic acids with cations in water; The water containing this inorganic acid is replaced by anion exchange resin (commonly used as strong basic anion of styrene) OH-, which combines with H+ in water to form water, which is deionized water.
Space water: The water produced by reverse osmosis was later used as drinking water for astronauts in space flight, so it was called "space water".
Distilled water: pure water obtained by distillation, that is, water obtained by collecting steam and heating and cooling. Natural water is impure, and usually contains various salts such as calcium, magnesium and iron, as well as organic matter, microorganisms, dissolved gases (such as carbon dioxide) and suspended solids. The nonvolatile components can be removed by distillation.
Magnetized water: It is a kind of water magnetized by a magnetic field. Let ordinary water cut along the direction perpendicular to the magnetic field lines at a certain speed, and through a magnetic field with a certain intensity, ordinary water will become magnetized water.
Hard water: refers to the high concentration of minerals in water. These minerals are mainly composed of calcium ions and magnesium ions, sometimes including other bicarbonate and sulfide. Generally speaking, hard water is harmless to human body. Preliminary research shows that minerals in hard water have a positive (though weak) promoting effect on cardiovascular health. Too soft water (containing very few minerals) contains metals such as copper, lead and zinc because it will corrode the pipe wall when flowing through metal pipes, which will have a bad impact on human health.
Although hard water is harmless to human body, we usually have to soften it. This is because hard water will bring a lot of troubles to our life, for example, water containers and boiling water will form scale on the inner wall of pipes, and the washing effect of soap and detergent will be reduced. There are many ways to soften hard water. One of the easiest ways is to boil hard water and let the minerals precipitate to the bottom of the pot. In addition, we can also use precipitation method (treating with lime and soda ash to precipitate calcium and magnesium ions in water, and then filtering) and softener method. Softeners are some chemicals with excellent complexing power to metal ions such as calcium and magnesium, which are widely used in practice (such as textile printing and dyeing).
master ['mɑ:st？ ] n。
Master (male); Master; Head of household; Commander; Employer; A person in control, a ruler
Parents; captain
Male teacher; Principal; Master, master; Famous artists and experts; Famous works
Master [master]
[Used before a person's name] ... Small boss
How many kinds of messages does ospf always have? Usually, there are five kinds of messages.
Hello message (type 1).
Database Description Message (Type 2).
Link state request message (type 3).
Link State Update Message (Type 4).
Link state response message (type 5).