Mendeleev
The discovery of the periodic law of elements
In 1867, a young chemistry professor came to Petersburg University in Russia. Mendeleev. As a professor of chemistry, Mendeleev spent most of his time not in the laboratory, but in his study. I always hold a deck of cards in my hand, tossing them around, arranging them, shuffling them, and rearranging them again. I don’t invite poker friends, and I don’t go to other people’s poker tables.
One day two years later, the Russian Chemical Society specially invited experts to conduct an academic discussion. Some scholars brought papers and some brought samples. Only Mendeleev was empty-handed. The academic discussion lasted for three days. During the three days, everyone expressed their opinions in the discussion venue. It was very lively. Only Mendeleev remained silent. I just stared with my big eyes, listened with my ears, and sometimes frowned and thought about it.
Seeing that the discussion was about to end, the host bowed and said, "Mr. Mendeleev, do you have any suggestions?" Mendeleev did not say anything, stood up and walked to the center of the table with his right hand. He took it out of his pocket and threw a deck of cards on the table. Everyone present was shocked. Mendeleev loved to play cards. His friends in the chemical industry had already heard about it, but he never got into trouble like this. Are you joking in a serious situation?
I saw Mendeleev holding the messy cards in his hand, sorting them out in a few clicks, and showing them to everyone one by one. Only then did everyone realize that this was no ordinary deck of cards. Each card was written with the name, properties, atomic weight, etc. of an element. There were 63 cards, representing the 63 elements that had been discovered at that time. What's even more strange is that there are seven colors in this deck of cards: red, orange, yellow, green, cyan, blue, and purple.
Mendeleev is truly a veteran of playing cards. After a while, he formed a card array on the table: vertically, there are one row each of red, orange, yellow, green, cyan, blue and purple. , looking at the cards of seven colors horizontally, they are like drawn spectrum segments, repeating regularly every seventh card. Then Mendeleev talked about the properties of each element in his mouth, knowing it so well that he counted it like a treasure. People around were dumbfounded. They have been working in the laboratory for ten or several decades, but they never thought that a young man could come up with this truth just by playing cards. To say that they are not convinced, it seems to be reasonable, but to say that it is really the case, they are a little unwilling to accept it.
At this time, Mendeleev's teacher, who had been sitting nearby and watching, raised his beard in anger. He slapped the table and stood up. He said in a stern tone of teacher: "Put away this magic trick of yours." "As a professor and scientist, you don't do experiments honestly in the laboratory, but you want to discover some rules by playing cards. Are these elements just at your mercy..." The old man became more and more excited as he spoke. He packed up his things and prepared to leave. Seeing this, other people stood up one after another, and the discussion ended like this.
Mendeleev firmly believed that he was right. After returning home, he continued to push the deck of cards. Filling in an empty card, he predicted 11 unknown elements in one breath, and the deck of cards already had 74 cards. This is the earliest periodic table of elements.
In the following years, the 11 elements predicted by Mendeleev were discovered one after another and settled into his periodic table of elements, especially the later discovered helium, neon, argon, krypton, Xenon and radon add a new group to the periodic table of elements. The world of elements is clear at a glance, it is like a big map, and future chemical research will all rely on this guide map.
Newton
The young Newton did not show eye-catching scientific genius from an early age like Gauss or Wiener; nor did he show amazing artistic talent like Mozart. endowment. Like ordinary people, he spent his middle school years happily and relaxedly.
If there is any difference between him and other children, it is that his hands-on ability is quite strong. He made a movable waterwheel; a water clock that could measure accurate time; and a waterwheel and windmill linkage device that enabled the windmill to be driven by water power when there was no wind.
When he was 15 years old, a rare storm hit England.
The wind roared violently, and the Newton's house swayed as if it was about to fall. Newton was fascinated by the power of nature and couldn't help but want to test the power of hurricanes. He braved the storm and came to the backyard, sometimes running against the wind and sometimes jumping with the wind. In order to receive more wind force, he simply opened his cloak and jumped upwards, looking for the starting and landing points, carefully measuring the distance to see how far the strong wind would blow him.
In 1661, Newton was admitted to Cambridge University. Although he was an top student in middle school, Cambridge University concentrated top students from all over the world, and his academic performance could not keep up with others, especially in mathematics, where the gap was even greater. But he was not discouraged, just as he liked to think about problems when he was a boy, and studied steadily until he understood it thoroughly.
In the first two years of college, in addition to studying arithmetic, algebra, and trigonometry, he also carefully studied Euclid's "Elements of Geometry" to make up for his past deficiencies. He also studied Descartes's "Geometry" and mastered the coordinate method skillfully. This mathematical knowledge laid a solid foundation for Newton's later scientific research.
Four years later, he graduated from Cambridge University. One day in 1666, Newton invited his mother and siblings to come to his room. The room was dark, with only a ray of sunlight coming through a small hole in the window, illuminating a white spot on the wall. Newton asked them to look at the spots of light on the wall. He held a homemade prism in his hand and placed it at the entrance of the light, causing the light to refract to the opposite wall. A magnificent ribbon suddenly appeared near the light point. This ribbon is the same as the rainbow that appears in the clear sky after rain. It is composed of seven colors: red, orange, yellow, green, cyan, blue and purple. Newton and his relatives watched the artificially reproduced natural scenes together. Later, Newton used a second prism to synthesize seven kinds of monochromatic light into white light. He announced the birth of spectroscopy with his white light decomposition experiment.
While Newton was exploring the mystery of light and color, he was also exploring the mystery of gravity. He discovered the law of universal gravitation from the fact that the apple fell from the tree, mathematically demonstrated the law of universal gravitation, and established mechanics as a complete, rigorous, and systematic discipline. On the basis of summarizing and summarizing previous research results, and through his own observations and experiments, he proposed the "Three Laws of Motion". These three laws and the law of universal gravitation together form the main pillars of the magnificent mechanics building. This mechanics building is the base for the development of modern astronomy and mechanics, the base for the development of engineering technologies such as machinery and architecture, and the base for the dominance of mechanical materialism in the field of natural sciences. A magnificent mechanical building was constructed.
Watt
Watt was born in Greenock, England. Due to his poor family, he had no chance to go to school. He first worked as an apprentice in a watch shop, and then worked as an instrument repairman at the University of Glasgow. Smart and eager to learn, he often took time to sit in on professors' lectures. In addition, he personally played with the instruments all day long, so he accumulated a lot of knowledge.
In 1764, the University of Glasgow received a Newcomen steam engine that required repair, and the task was assigned to Watt. After Watt repaired it, he saw how hard he was working, like an old man panting and trembling while walking with a heavy load. He felt that it should be improved.
He noticed that the main problem was that the cylinder heated up and then cooled down, and cooled down and heated up again each time as the steam heated up, which wasted a lot of heat. Can it be kept cold and the piston work as usual? So he rented a cellar with his own money, collected several scrapped steam engines, and determined to build a new machine.
From then on, Watt played with these machines all day long. Two years later, he finally came up with a new machine. But after trying to ignite it, the cylinder leaked air everywhere. Watt tried his best to wrap it with felt and oilcloth. Several months later, he still couldn't cure the problem.
One day he lay down in front of the cylinder to observe the cause of the air leakage. Unexpectedly, a burst of hot air rushed out. He hurriedly dodged. His right shoulder was already red and swollen, as if he had been sliced ??by a hot knife. , it hurt sharply, making him upset. He was really discouraged. At this time, it was his wife who gave him the courage, and his wife used provocation to arouse his ambition to continue his research.
He returned to the underground laboratory, read through the past materials again, cheered up and started working again. When he was tired, he would stand by the stove and boil a pot of water for tea. One day, while drinking tea, he looked at the moving lid. He looked at the kettle on the stove and then at the cup in his hand, and suddenly an inspiration came to him: the tea needs to be cold, so pour it into the cup; the steam needs to be cold, why not "pour" it out of the cylinder too?
With this in mind, Watt immediately designed a condenser that was separate from the cylinder. This tripled the thermal efficiency and used only a quarter of the original coal. Once this key point was broken through, Watt suddenly felt that his future was bright. He went to the university to ask Professor Black for some theoretical questions, and the professor introduced him to technician Wilkin who invented the boring machine. The technician immediately used the method of boring the barrel to make the cylinder and piston, solving the most troublesome problem. Air leakage problem.
In 1784, Watt's steam engine was equipped with a crankshaft and flywheel. The piston could be continuously pushed by steam coming in from both sides. There was no need for manpower to adjust the valve. The world's first real steam engine was born.
Yang Zhenning
Yang Zhenning was born in Hefei, Anhui. When he was in elementary school, his math and Chinese scores were very good. Before graduating from middle school, he was admitted to Southwest Associated University when he was only 16 years old. After graduating from college at the age of 20, he immediately entered the graduate school of Southwest Associated University. Two years later, he obtained a master's degree with honors and was admitted to a publicly-funded study abroad program in the United States. In 1945, he went to the United States to study at the University of Chicago, and received his doctorate in 1948. In 1949, Chen Ning Yang entered the Institute for Advanced Study in Princeton as a postdoctoral fellow and began to collaborate with Tsung-Dao Lee on particle physics research.
Zhenning Yang is a theoretical physicist. His contributions to theoretical physics are wide-ranging, including the fields of elementary particles, statistical mechanics and condensed matter physics, among which he has made the greatest contribution to particle physics.
In particle physics, his most outstanding contribution is the Yang-Mills field theory jointly proposed with Charles Mills in 1954, which opened up new research on non-Abelian gauge fields. field, laying a solid foundation for modern gauge field theories including electroweak unified theory, quantum chromodynamics theory, grand unified theory, and gauge theory of gravitational fields.
Another outstanding contribution was his cooperation with Li Zhengdao in 1956, which led to an in-depth study of the then puzzling mystery of θ-τ, that is, the so-called K meson has two different decay methods, one is One decays into an even parity state, and the other decays into an odd parity state; if parity is conserved in the weak decay process, then they must be K mesons with two different parity states. But from the perspective of mass and lifespan, they should be the same kind of meson.
Through analysis, Yang Zhenning and Li Zhengdao realized that parity may not be conserved in weak interactions. They carefully examined all past experiments and confirmed that they did not prove parity conservation in weak interactions. On this basis, they further proposed several experimental ways to test parity non-conservation in weak interactions. The following year, this theoretical prediction was experimentally confirmed by Wu Jianxiong's group, for which they won the 1957 Nobel Prize in Physics.
In terms of particle physics, Chen Ning Yang’s contributions also include the Fermi-Young model, the two-component neutrino theory in collaboration with Tsung-Dao Lee, and the work on electric charge in collaboration with Tsung-Dao Lee and R. Ochme. ***Analysis of non-conservation of yoke transformation and time inversion transformation, high-energy neutrino experimental analysis and research on W particles in collaboration with Li Zhengdao. The parity non-conservation analysis in collaboration with Wu Dajun, the integral form theory of gauge fields, and the relationship between gauge fields and fiber bundles in collaboration with Wu Dajun. High-energy collision theory in collaboration with Zou Zude, etc.
Yang Zhenning remembers the legacy of his father Yang Wuzhi: You should remember the country's kindness while you are alive. In the summer of 1971, he was the first American scientist to visit China. He said: "As an American scientist of Chinese descent, I have the responsibility to help build a bridge of understanding and friendship between these two countries that are closely related to me. I should contribute some strength to the development of China's science and technology." This is what Yang Zhenning said and what he did. For more than 20 years, he has traveled frequently between China and the United States and has conducted many fruitful academic contacts.
David
David was a famous prodigal son when he was a child. Although he was smart, he just didn't want to learn. When he goes to school, he always carries a fishhook and line in one pocket and a slingshot in the other pocket. Before going to school, he always goes to the river to shoot a few birds and catch a few fish.
After his father died, his mother couldn't survive with five children, so she had no choice but to send David to a pharmacy as an apprentice. At the end of the month, others were paid, but not David. David reached out to the boss to ask for it, but the boss hit David hard in front of everyone and said, "I asked you to grab medicine without knowing the prescription, and asked you to deliver medicine without knowing the house number. How dare you reach out and ask for money?" The masters and apprentices in the store burst into laughter.
David had never experienced such humiliation. From then on, he made up his mind to turn back his prodigal son and study hard. He used the conditions of the pharmacy to study chemistry. At this time, Professor Bedos happened to have established a gas sanatorium, and David was invited to work together. Here, David discovered a kind of "laughing gas", and David's reputation grew from then on.
In 1803, David was elected as a member of the Royal Society. He knew the opportunity was rare, so he studied harder. Among many research topics, David was particularly interested in the electrolysis of voltaic cells. He thought that if electricity can decompose water into hydrogen and oxygen, it must also be able to decompose other substances into new elements. Caustic alkali is commonly used in chemistry, so you might as well give it a try.
So he mixed a piece of caustic alkali into an aqueous solution, and then turned on electricity. The solution immediately boiled and heated, and bubbles appeared near the two wires. At first David thought that the caustic alkali had decomposed, but later he discovered that the gases that escaped were hydrogen and oxygen, which meant that only water was decomposed, and the caustic alkali did not move at all.
David's stubbornness is rising. If water attack doesn't work, he will use fire attack. This time he melted the caustic alkali and then turned on the electricity, hey! Small tongues of flame, a light purple color, appeared where the wires came into contact with the caustic alkali. This made David very happy, but he soon became worried again. How to collect this substance? The temperature of the molten material is too high, and it is flammable. It will catch fire as soon as it decomposes. It seems that fire attack is not a good idea either.
November 19th is the day of the Royal Society’s annual Becair Lecture, and David fully hopes to get a newly discovered element this time. However, as the report date is approaching, electrolytic caustic alkali still has no clue. He thought hard for more than ten days, and this day he suddenly came up with a good idea: slightly wet the caustic alkali so that it could conduct electricity without containing any remaining moisture.
It is very simple to wet the caustic alkali. Just put it in the air for a moment, and it will automatically absorb moisture and form a wet layer on the surface. This time David really succeeded. He electrolyzed potassium metal.
Qian Sanqiang
While studying in France, Qian Sanqiang was engaged in research on nuclear physics at the Curie Laboratory of the Radium Institute of the University of Paris and the Nuclear Chemistry Laboratory of the Collège de France. During this period, Qian Sanqiang made many achievements in the field of nuclear physics.
First, he collaborated with Joliot Curie to use neutrons to attack uranium and thorium to obtain radioactive lanthanum isotopes. Their beta-ray energy spectra proved that they were the same isotope. This is strong support for explaining the nuclear fission phenomenon that was discovered shortly at that time.
He also determined theoretically and experimentally for the first time the relationship between the range and energy of low- and medium-energy electrons below 50,000 electron volts. In collaboration with Bouissière and Bachelet, the fine structure of protactinium's α-rays was measured for the first time, and it matched well with the γ spectral line of electron internal conversion.
His greatest achievement was the discovery of the three-fission and four-fission phenomena of uranium in collaboration with his wife He Zehui and two French graduate students, Chastelle and Micronéron. This discovery made them extremely excited, but they did not publish it immediately because scientists at the time agreed that only binary fission was possible when the nucleus split. Qian Sanqiang continued to analyze and study based on experiments, and finally came up with the relationship between energy and angular distribution, etc., and made a comprehensive discussion of the three-splitting phenomenon from both experimental and theoretical aspects.
After more than ten years of testing, this discovery has been recognized, especially after the acquisition of new experimental methods in the 1950s. The isotope mass spectrum, range, emission angle, etc. of the second fragment all prove that it is The explanation is consistent with experimental evidence and computer calculation results. This discovery is considered to be the first important result of the Curie Laboratory and the Nuclear Chemistry Laboratory of the Collège de France after World War II.
When Qian Sanqiang was about to return to his motherland, Joliot Curie and his wife gave him an appraisal certificate, which read: During the ten years, we will guide the work of those who come to our laboratory. Among his contemporaries, Qian Sanqiang is the most outstanding. We are not exaggerating when we say this.
After Qian Sanqiang returned to China, he trained a group of talents engaged in nuclear science research and established a base for nuclear science research in China. Since 1955, he has participated in the establishment and organization of the atomic energy industry, transformed the Institute of Modern Physics into the Institute of Atomic Energy, led and promoted the development of this undertaking and related scientific and technological work, and contributed greatly to the Chinese Academy of Sciences and China's atomic energy industry. have contributed to its construction, planning and academic leadership.
Nobel
Nobel’s father was a talented inventor who was devoted to chemical research, especially the study of explosives. Influenced by his father, Nobel showed a tenacious and brave character since he was a child. He often went to experiment with explosives with his father. After many years of studying explosives with his father, his interest soon turned to applied chemistry.
In the summer of 1862, he began research on nitroglycerin. This is an arduous journey full of danger and sacrifice. Death was always with him. An explosion occurred during an explosives experiment. The laboratory was blown up without a trace, and all five assistants died. Even his youngest brother was not spared. This shocking explosion dealt a very heavy blow to Nobel's father, and he died not long after. Out of fear, his neighbors also complained to the government about Nobel. After that, the government did not allow Nobel to conduct experiments in the city.
But Nobel was unyielding and moved his laboratory to a boat in a lake on the outskirts of the city to continue his experiments. After long-term research, he finally discovered a substance that is very easy to cause explosions - mercury fulminate. He used mercury fulminate as a detonator for explosives and successfully solved the problem of detonating explosives. This was the invention of the detonator. It is a major breakthrough on the road to Nobel science.
Mining development, river excavation, railway construction and tunnel excavation all require a large amount of high explosives, so the advent of nitroglycerin explosive has been generally welcomed. Nobel built the world's first nitroglycerin factory in Sweden, and later established joint ventures abroad to produce explosives. However, the explosive itself had many imperfections. It will decompose if stored for a long time, and strong vibration can also cause explosion. Many accidents occurred during transportation and storage. In response to these situations, the governments of Sweden and other countries issued many bans, prohibiting anyone from transporting the explosives invented by Nobel, and clearly proposed to pursue Nobel's legal responsibility.
Faced with these tests, Nobel was not intimidated. Based on repeated research, he invented a safe explosive using diatomaceous earth as an absorbent. This safe explosive is called yellow explosive. Explosives, exhibit great safety both by fire and by hammering. This completely lifted people's doubts about Nobel's explosives. Nobel once again gained credibility, and the explosives industry also developed rapidly.
Based on the successful development of safe explosives, Nobel began research on the improvement of old explosives and the production of new explosives. Two years later, a new type of colloidal explosive mixed with gunpowder cotton and nitroglycerin was successfully developed. This new type of explosive is not only highly explosive, but also safer. It can be rolled between hot rollers or pressed into a rope shape under hot air. The invention of colloidal explosives has received widespread attention in the scientific and technological circles. Nobel did not stop in the face of the achievements he had made. When he learned about the superiority of smokeless gunpowder, he invested in the development of mixed smokeless gunpowder, and developed a new type of smokeless gunpowder in a short period of time.
Nobel made many inventions in his life, and obtained 255 patents, including 129 types of explosives alone. Even when he was dying, he still couldn't forget his research on new explosives.
李正道
Li Zhengdao was born in Shanghai. He loved reading since he was a child. He kept reading books all day long. He even took books with him to read when he went to the bathroom. Sometimes he didn’t bring toilet paper, but the books never came. Forgot. During the Anti-Japanese War, he traveled to the southwest to study. He lost all his clothes along the way, but not a single book was lost. Instead, he lost more and more books each time.
In 1946, 20-year-old Li Zhengdao went to the United States to study. At that time, he only had a sophomore degree. However, after passing a rigorous examination, he was admitted to the Graduate School of the University of Chicago. Three years later, he passed the doctoral thesis defense with "special insights and achievements" and was known as the "Doctor Prodigy". He was only 23 years old at the time.
Lee Tsung-dao's outstanding contribution to modern physics is: in 1956, he collaborated with Yang Zhenning to conduct an in-depth study of the then puzzling θ-τ mystery, and proposed the "Li-Yang hypothesis", which was Parity may not be conserved in the weak interaction of elementary particles. Later, this hypothesis was confirmed experimentally by Chinese female physicist Wu Jianxiong, thus overturning the law of parity conservation that was regarded as a golden rule in the physics community in the past. Human beings have opened a new door in exploring the microscopic world. He also won the 1957 Nobel Prize in Physics.
This is the first time that a scientific work has won the Nobel Prize in the second year after its publication. Lee Tsung-dao was the second youngest Nobel Prize winner in history up to that time.
Lee Tsung-dao's other important works include:
In 1949, he collaborated with M. Rosenbluth and Yang Zhenning to propose the universal Fermi weak interaction and intermediate bosons. existence.
In 1951, it was proposed that there is no turbulence in two-dimensional space in hydraulics.
In 1952, he collaborated with D. Pines to study the structure of polarons in solid state physics. In the same year, he collaborated with Chen Ning Yang and proposed the Yang Zhenning-Li Zhengdao theorem and Li-Yang single circle theorem about phase transition in statistical physics.