Russian chemist Mendeleev

Russian chemist Mendeleev was born in Polsk, Siberia. 1855 became a middle school chemistry teacher after graduating from Petersburg Teachers College; 1856 received a doctorate; 1857 Associate Professor, University of Petersburg; 1859 went to Germany for further study, specializing in physical chemistry; 186 1 returned to China and became a professor at the University of Petersburg.

When I was a child, Mendeleev's family was very poor. The whole family has 17 children, and Mendeleev ranks first 14. Only a few months after President Ren Zhongxue was born, his father lost his presidency because of sudden blindness and retired home. The meager pension can't support such a large family, so the whole family had to move to a village near Tuo Polsk. His uncle runs a small glass factory there, and his mother helps manage the factory there and does some sideline work in the yard of the factory, so life begins to improve. At that time, Mendeleev was still very young, and he often sneaked into the factory to see how the workers melted and processed glass, which had a great influence on his future chemical research on beakers and flasks.

184 1 autumn, Mendeleev was admitted to Tuo Polsk Middle School with his brother when he was less than 7 years old, which became a local sensation. But misfortune always accompanies the Mendeleev family. /kloc-at the age of 0/3, my father died, and my sister died three months later. A year later, the factory was burned to ashes, and my mother had to lead the whole family to move back to the countryside. /kloc-in the spring of 0/849, Mendeleev graduated from middle school, and her mother sold her property and took her children to Moscow. She really wants this little son to go to college, because the teachers agree that he has excellent wisdom and talent. My mother ran around the university in Moscow to no avail, and finally decided to try her luck in Petersburg. Her husband's friends were in important positions at that time. With his help, Mendeleev was admitted to Petersburg Normal College where his father was studying, because the students there were completely free.

Mendeleev studies physics. For poor students from small places, the threshold of Petersburg Normal College is too high. However, after only one year, he became a top student. In addition to intense study, Mendeleev began to write a brief summary of scientific achievements and received a small amount of manuscript fees, which was his only income. Because, by this time, he has lost any financial support. My uncle passed away; Soon, my little sister also died of lung disease; Finally, even the loving mother left this world. 1854 Graduated from Mendeleev University. He won the gold medal awarded by the college with the first place in his class. He became an associate professor at the age of 23 and was promoted to full professor at the age of 3/kloc-0.

Mendeleev can grow from a poor child in a small Siberian city to a full professor at Petersburg University without his consistent efforts. It was his organic chemistry that made Mendeleev gain his initial fame. In order to write this book, he never left his desk for almost two whole months. He often works day and night and takes less than a few hours off at noon. After the age of 70, Mendeleev was semi-blind because of overwork. But he still works from early morning until 5: 30 in the afternoon, and then has lunch. Continue to write after dinner. He was sitting in a chair with a pen in his hand when he died.

Mendeleev was one of the discoverers of the periodic law of chemical elements. There are 63 elements found before 1869. In order to explore the laws between elements, many chemists have studied the classification of elements. On the basis of previous studies, Mendeleev made various classifications, comparative analysis and comprehensive induction according to the properties of elements, and finally found the periodic changes between the properties of elements and atomic weight. 1869, he officially published the periodic law of chemical elements and predicted some undiscovered elements according to this law. As the basic law of nature, the periodic law of elements reveals the secrets of the material world and greatly promotes the development of modern chemistry and physics. Engels praised it as "a great achievement in scientific research".

Mendeleev put forward the theory of solution hydration, which laid the foundation of modern solution theory. He studied the relationship between the volume of gas and liquid and humidity and pressure, and found that the critical temperature of gas was 1860.

Mendeleev put forward the viewpoint of underground coal gasification for the first time, which put forward a broad prospect for the wide application of coal gasification. He also made some contributions in petroleum industry, agricultural chemistry and smokeless gunpowder. He is also a weather explorer. In order to study the upper atmosphere and observe the solar eclipse, he risked his life in August 1887 and manipulated a balloon to ascend into the sky for detection. This spirit of not being afraid of sacrifice left a deep impression on people. In Mendeleev's words, "For me, the best rest is work. If I stop working, I will be bored to death. "

He really worked until the last moment of his life. 190765438+1On the morning of October 20th, Mendeleev passed away. The news of the great scientist's death shocked the whole Russian society. The funeral was grand, and the road leading to Volcker cemetery was crowded with people on both sides. In the funeral procession, there was a big banner that read "Periodic Table of Elements". Flags are flying in the north wind, spreading the immortal name of this great scientist in all directions.

The outstanding astronautics is Qian Xuesen.

Qian Xuesen, 19 1 1 was born in Shanghai and his ancestral home was in Hangzhou, Zhejiang. He finished high school in the middle school affiliated to Beijing Normal University. In middle school, Qian Xuesen made up his mind to study hard for the prosperity of the motherland. He studies very hard and his grades are always among the best. At that time, there were many courses for middle school students. In high school courses, there are advanced algebra, analytic geometry, calculus, physics, chemistry and so on. Because of his genius and superhuman memory, he didn't feel too much pressure. He also took inorganic chemistry, industrial chemistry, English and German. Recalling his middle school life, he said with emotion, "Of all the education I have received in my life, the education in the attached middle school is a very good one that I miss so far."

Because of his high courses in middle school and good grades, he studied more easily after entering the university, but he still worked hard. He is determined to get more than 90 points in every exam. Results The average score of each semester was over 90 points, and tuition was free.

1935, after graduating from department of mechanical engineering, Shanghai Jiao Tong University, Qian Xuesen was admitted to the United States to study abroad at public expense. The following year, he received a master's degree from MIT. Later, he went to California Institute of Technology for further study, became one of the founders of space science in the United States, was a favorite pupil of the famous aerodynamics professor von Carmen, and was known as the "father of supersonic flight". He got a doctorate and went on to be a teacher.

During this period, Qian Xuesen eagerly studied mathematics, partial differential equations, integral equations, atomic physics, quantum physics, statistical mechanics, relativity, molecular structure, quantum chemistry and so on. Three years later, he stood at the forefront of modern mathematics and mechanics. Later, it only took 1 year to study the aviation structure, and a breakthrough was made. Professor von Carmen not only directed Qian Xuesen's research, but also recommended this talented young scientist to participate in many important and even highly confidential engineering and technical work in the United States. Qian Xuesen accomplished the task brilliantly every time and left a deep impression on Professor Von Carmen. The professor was satisfied with Qian Xuesen's work and said, "You have surpassed me academically now."

From 65438 to 0943, after careful selection, the US military entrusted Qian Xuesen to study the important topic of using rocket engines to propel missiles. In June165438+1October of the same year, he cooperated with Marina to present a research report. This report laid the foundation for the successful development of surface-to-surface missiles and sounding rockets in the United States in the 1940s and 1950s, and became the pioneer of composite propellant rocket engine missiles in the United States. From 65438 to 0949, he returned to California Institute of Technology as the head of the jet propulsion course and the Guggenheim Jet Propulsion Research Center. He began to study nuclear engines and wrote the first excellent paper on nuclear rocket technology. At the end of World War II, the US military highly praised Qian Xuesen for his "great and inestimable contribution" to the victory of the anti-fascist war. Qian Xuesen is regarded as "a bright star in the galaxy of scientists who helped the United States become a world-class military power" and "a key figure in long-term planning for the transformation from propeller to jet and finally to unmanned spacecraft flying in space". At this time, Qian Xuesen has become a world-recognized authority on mechanics, applied mathematics and rocket technology, one of the pioneers of fluid mechanics, an outstanding aerodynamist, a pioneer of modern aviation science and aerospace technology, and the founder of engineering control station.

1949 Mid-Autumn Festival night, full moon and quiet night. Qian Xuesen spent the Mid-Autumn Festival with a dozen China students around him. Looking up at the bright moon and sinking back, I suddenly remembered home. They miss their motherland and convey the good news of the birth of new China, one by one in anxious to return. That night, they quietly discussed the plan to return to China.

Unexpectedly, in order to return to his liberated motherland, Qian Xuesen went through hardships and endured torture and imprisonment for more than five years. He suffered great physical and mental damage and lost 30 pounds.

1954, Qian Xuesen wrote the book "Engineering Cybernetics" with 300,000 words. He said, "This is written for the American authorities." The purpose is to let them know that they have changed their research direction, so that they can return to China as soon as possible. On August 2nd, 1955, Wang Bingnan, the ambassador of China, was entrusted by Premier Zhou Enlai to expose the despicable behavior of the US authorities in imprisoning Qian Xuesen, a citizen of China, against his will and preventing him from returning to China. The United States was forced to allow Qian Xuesen to leave the United States and return to New China on August 4th.

From 65438 to 0956, Qian Xuesen was appointed as the director of the Missile Research Institute of the Fifth Research Institute of the Ministry of National Defense. That year, the Soviet Union tore up the contract and withdrew the experts. It was Qian Xuesen who led our own experts, independent and self-reliant, who developed China's first missile in a short time, and then conquered medium-sized missile technology and rocket technology. Qian Xuesen firmly believes: "If foreigners can do it, why can't China people do it?" Under his leadership and organization,1June 29th, 964, the flight test of China's first self-designed medium and short-range missile was successful. Then the "two-bomb combination" flight test was carried out, and the atomic bomb was carried by a medium-range missile. The missile flew normally, and the atomic bomb exploded at a predetermined distance and height, which indicated that China began to possess missile nuclear weapons for self-defense.

1970 On April 24th, Qian Xuesen and other scientists successfully launched China's first artificial satellite, weighing 173kg. The music "Dongfanghong" played by this satellite to the whole world heralds the new dawn of the new China space age.

Every achievement in the space industry has been devoted to Qian Xuesen's painstaking efforts and wisdom, and he has devoted all his wisdom and wisdom to the national space industry. He summed up the development experience of China's missile weapons and spacecraft systems, refined engineering cybernetics into systems engineering theory, and extended it to military logistics, social economy, social legal system, agricultural ecology, human science, thinking science, behavioral science, aesthetics and other fields, which played an important role in social progress and scientific development.

Qian Xuesen has a wide range of hobbies and is versatile. He likes music, art and calligraphy. He was also a famous brass musician when he was a student. He collaborated with his wife, Jiang Ying, a professor at the Central Conservatory of Music, to write articles on the development of music.

Qian Xuesen loves the motherland and loves the socialist motherland even more. Obviously, he gave up his comfortable living conditions, broke through many obstacles and threw himself into the embrace of his motherland. Qian Xuesen loves the people. He said, "As a scientist in China, the purpose of living is to serve the people. If the people are finally satisfied with the work I have done in my life, it will be the highest reward for me. "

Outstanding mathematician Hua

In the wild land of modern mathematics in China, a pioneer insisted that "a soldier is lucky to die on the battlefield". He is Hua. Hua is the founder of China's research on analytic number theory, typicality theory, matrix geometry, automorphic function theory and complex variable function theory, and he is also the most outstanding representative of China's entry into the world-famous mathematics ranks. His research achievements are named Fahrenheit Theorem, Brouwer-Gadang-Hua Theorem, Hua-Wang Method, Fahrenheit Operator and Fahrenheit Inequality by international mathematicians. He left us more than 200 academic papers and 65,438+00 monographs in his life, 8 of which were translated and published abroad, and some of them have been included in the classics of this century. He creatively applied mathematical methods to the field of national economy, and screened out the "optimization method" with the content of improving mathematical methods for technical problems and the "overall planning method" with the content of dealing with production, organization and management problems. He is the first China scholar to be elected as a foreign academician in the history of American Academy of Sciences. He was also elected as an academician of the Bavarian Academy of Sciences in the Federal Republic of Germany; He was awarded an honorary doctorate by Nancy University in France, the University of Illinois in the United States and the Chinese University of Hong Kong. His name entered the Smithsonian Museum in Washington, USA, and was listed as one of the 88 great mathematicians in the Chicago Museum of Science and Technology.

Tears welled up in his eyes when the news of the founding of New China reached the United States. To rebuild my home. He did not hesitate to give up his tenured professorship at the University of Illinois, leaving behind a generous salary, a car and a house. Enthusiastic, he and his family boarded a ship and returned to the embrace of the motherland in the spring of 1950.

After returning home, he filled in the column of educational level of the household registration book: "graduated from junior high school". This is an unforgettable sentence for China, but it is a puzzling thing for others. What the hell is going on here? Let's look at his road to success.

19101012. Hua was born in a poor family in Jintan County, Jiangsu Province. Father opened a small grocery store and barely made ends meet. Hua/Kloc-graduated from junior high school in Jintan county at the age of 0/5, and then went to Shanghai China Vocational School. Because my family is poor, I can't afford the meal. They only studied 1 year and then left school.

Hua has been smart and studious since childhood. In junior high school, he showed a special talent in math class. One day, Mr. Wang Weike gave the class a math problem, which was a topic in Sun Tzu's Art of War: "There are unknowns at present, three counts leave two, five counts leave three, and seven counts leave two." What is the geometry of things? " When Mr. Wang was reading this question, he read slowly and his voice was cadenced. After reading the topic, Mr. Wang swept his eyes to the whole class, and his eyes were full of nervous and confused faces. Suddenly, a student stood up and said, "There are 23 items." This is a familiar voice that awakens students from thinking and doubts. Everyone looked at him with amazing eyes. The first student to tell the answer is young Hua. When solving this problem, Hua thinks like this: starting from "the number of seven plus seven gets two", that is, seven gets two, then the multiple of seven plus two is this number, so it is not necessary to assume that this number is 7 × 3+2 = 23. Divide 23:23 by 3, leaving 2; 23 is divided by 5, so 23 meets the requirements of the topic. It is precisely because Hua was diligent and eager to learn since he was a child that Teacher Wang Weike paid more attention to his intelligence. Mr. Wang was deeply impressed by Hua when he was at school.

At the age of 0/8, Mr. Wang Weike became the principal of Jintan County Middle School. President Wang cherishes talents and invites Hua to be an accountant and do daily work at school. Since then, Hua has become busier. Recalling the experience during this period, he said, "In addition to the heavy affairs at school, I have to help my mother manage the affairs of the small shop sooner or later. I can't go home until around 8 o'clock every night. After clearing the account of the small shop, you can study mathematics, often late at night. " In other words, even after busy business, Hua never forgot to study mathematics, so his mathematics level is constantly improving.

When Hua 19 years old, by chance, he borrowed a magazine named "Learning Arts" and published the article "The Solution of Algebraic quintic Equation" written by Professor Su Jiaju in the seventh volume of this magazine, which aroused China's strong interest. After reading and thinking, Hua found that there were fundamental mistakes in the article. So he asked President Wang, "Can you write an article criticizing the mistakes in Professor Su's article?" Hua's question was definitely answered by President Wang: "Of course, saints are also at fault, so what can't be criticized!" Dean Wang is the translator of Italian poet Dante's masterpiece Divine Comedy. His words gave China great encouragement. Therefore, Hua wrote an article with strict logic and sufficient argumentation, which was reviewed and revised by Dean Wang and sent to Shanghai Science magazine. The article was published in 1930. As soon as the article was published, it attracted the attention of many people at that time. At that time, Professor Xiong Qinglai, head of the Department of Mathematics at Tsinghua University, saw this article. Moreover, I was even more shocked to learn that the author of this article was a junior high school boy in Jintan County with only a junior high school diploma. Seeing Hua's talent, he immediately wrote to Jintan Middle School and invited Hua to work in Tsinghua University. After receiving the letter, Hua thought twice: on the one hand, he remembered that before this, President Wang had asked him to teach a cram school in Jintan county junior high school, and because someone complained that President Wang had appointed an unqualified teacher (how could a junior high school graduate be qualified to teach junior high school), President Wang had to resign as president, and he no longer taught; On the other hand, because of his poor family, he even had difficulty traveling to Beijing, so he wrote back and politely declined Professor Xiong's invitation. After Professor Xiong received Hua's reply, the thirsty Bole wrote to urge him. The letter said: If you don't come, I will visit you in Jintan myself. Hua once again received a letter from Professor Xiong, from which he learned the sincerity and sincerity of his invitation. He felt that he had really failed Professor Xiong's kindness, so he had to borrow money from his father and was invited to Tsinghua.

In Tsinghua University, Hua became a teaching assistant. The main responsibilities are to manage books in the Department of Mathematics, send and receive official documents, collect stationery and draw charts. So that he can use his spare time to read books and listen to lectures. Under the arrangement and guidance of Professor Xiong, Hua made rapid progress in his studies, studied hard and often taught himself late into the night. It took him only one and a half years to complete the college course and four months to teach himself English, which can reach the level of reading English mathematics literature. In addition, he also taught himself German, especially after listening to the postgraduate courses, his mathematics literacy has been greatly improved and he has made new achievements. His three papers were published in foreign mathematical magazines, and Tsinghua University's teachers had to sit up and take notice of him. Soon, at a meeting of professors in Tsinghua University, it was decided to let him go to Tsinghua as a teacher with only junior high school education. It can be seen that Hua's success is mainly due to his own efforts. When talking about learning mathematics for middle school students, Hua said, "I am not afraid of difficulties, and studying hard is my main experience in learning mathematics well." He also said: "I don't despise easy questions. If I practice easy today, I will easily encounter difficulties tomorrow. I am not afraid of difficult problems, and I am always ready to solve them when necessary. I believe that as long as we work hard, there will be no insurmountable difficulties and no impregnable fortress. " This is how Hua studied hard before he became a university teacher from a young man with only junior high school education.

1936, Professor Xiong Qinglai recommended Hua to study at Cambridge University in England. 1938, Hua returned to the disaster-stricken motherland under the Japanese army's iron hoof, and was recommended by Professor Xiong Qinglai as Professor The National SouthWest Associated University at the age of 28. During his stay in The National SouthWest Associated University, Hua lived a very hard life. Their family lives in two small rooms in a small village on the outskirts of Kunming. There are pigsty and cowshed under the room, and the sanitary environment can be imagined. When recalling this life, Hua said, "A wait is like a bean overnight. The so-called lamp is just a broken cigarette can. Put an oil lamp and pick some broken cotton as a wick. In order to save vegetable oil, twist the core slightly. " At night, cows tickle, the earth shakes, and dangerous buildings are about to collapse! "Although Hua lived in such a box building and lived a hard life, he worked hard and made continuous efforts. It took him three years to write a mathematical manuscript called" The Theory of Prime Numbers in Stacking ". After writing "The Theory of Prime Numbers in Piles", Hua naturally intends to publish a book. So he translated the Chinese manuscript into English and sent it to the then "Academia Sinica", but Academia Sinica not only did not publish it, but also lost the manuscript. This is a great blow to China. Three years' efforts were in vain. Why not make him feel bad? Later, Hua sent an English version of The Theory of Iterated Prime Numbers to the then Soviet academician Victor Fu, and the English version was finally translated into Russian by the Soviet Union and published. After the publication of this book, it caused a shock in mathematics. After the founding of New China, The Theory of Overlapping Primes (Russian version) was translated into Chinese and published in China. For example, the theory of prime numbers on overlapping bases was first published in other countries and then in China, which is also a rare phenomenon in the world publishing history.

Hua went to school for nine years with only a junior high school diploma, but he became an outstanding mathematician with a good reputation at home and abroad. Hua's life is a life of hard struggle and a model of self-study. His motto "genius lies in accumulation, cleverness lies in diligence" reveals the secret of this success. His motto "Old trees are easy to be empty, old people are easy to be loose, the way of science, keeping empty and keeping loose" is worth remembering by future generations. The last wish of the giant who initiated modern mathematics research in China was "I really hope that the corpse can be useful to the revolution. Once the wall can be used as a ladder, crossing the ditch can be used as a bridge. "

Zu Chongzhi, a great scientist in the Southern and Northern Dynasties.

A German mathematician put it well: In the history of mathematical development, mathematicians in many countries are looking for more accurate pi, so the accuracy of pi can be used as a symbol to measure the level of mathematical development in this country. According to this statement, we can realize the great significance of Zu Chongzhi's brilliant achievements, from which we can see the height of the development of ancient mathematics in China.

Zu Chongzhi (AD 429 ~ 500) was born in Qixian County, Fanyang (now north of Laishui County, Hebei Province). He lived between the Southern Dynasties and the Song and Qi Dynasties and was an outstanding mathematician, astronomer and mechanical inventor in ancient China. Zu Chongzhi's outstanding achievements in mathematics shine brilliantly in the history of mathematics in the world, which is the pride of the Chinese nation. During the Southern Dynasties, economic prosperity and developed culture also put forward more urgent requirements for scientific and technological progress. This has created a good social foundation for Zu Chongzhi's scientific achievements. The ancestral family ruled the calendar for generations. Zu Chongzhi received a good family education since childhood, and was interested in natural science, literature and philosophy. He especially likes mathematics, astronomy and mechanical manufacturing, and studies hard. At that time, the Song government had an academic research institution called Hualin University, where Zu Chongzhi devoted himself to research in his youth. While studying the inheritance of genealogy, Zu Chongzhi studied the scientific achievements imported from ancient China and foreign countries. He read widely and learned hundreds of books, which laid a solid foundation for later scientific research.

When Zu Chongzhi was a child, he loved mathematics and astronomy and studied very hard. He "specializes in mathematics and collects ancient and modern", and collected almost all observation records and related documents preserved from ancient times to the 6th century as a reference. His research on pi began very early, and then he became obsessed. Legend has it that one day, the night was already deep, and he tossed and turned and couldn't sleep. The Weekly Calculator says that the length of a circle is three times its diameter. Is this correct? Before dawn, he woke up his mother, asked for a rope and ran to the road to wait for the carriage. Suddenly, a carriage came. Zu Chongzhi was overjoyed and asked to measure the wheels of the carriage. After repeated measurements, he always felt that the circumference of a circle was more than three times its diameter. How big is it? The question kept hovering in his mind until he was in his forties, when he solved the mystery.

Zu Chongzhi's most outstanding achievement is the accurate calculation of pi. Now we know that pi is the ratio of the circumference to the diameter of a circle. This is a constant, generally expressed by the Greek letter π. It has been proved that π is not only an irrational number, but also a transcendental number, that is, it can neither be accurately expressed by finite numbers nor by finite algebraic expressions. Zu Chongzhi's research on pi is included in his son Zuheng's works. What book is this?

It turns out that in order to spread the essence of mathematics and physics in China, the Tang Dynasty selected 10, a representative arithmetic book, as a textbook, which is called the Top Ten Calculation Classics, namely, Zhoupian Calculation Classics, Jiuzhang Calculation Classics, Island Calculation Classics, Sunzi Calculation Classics, Zhang Qiujian Calculation Classics, Cao Calculation Classics and Xiahou. It was not until Liu Hui, a mathematician in Wei and Jin Dynasties, took notes that people could understand its contents. Later, Zu Chongzhi felt that Liu Hui's annotation had not been completed, so he wrote dozens of monographs, which he called "composition". As a supplement to Liu Hui's note. "Seal Script" is a valuable scientific masterpiece, and its content is so profound that even the "scholars" at that time could not understand it. In the Tang dynasty, it was listed as a compulsory textbook for schools all over the country, and the study time was as long as four years, which was the longest time. Japan and Korea also used bamboo books as textbooks in the 12 century. Later, it was lost in Beizhong, which was a great loss in mathematics. What does "seal script" specifically include? It is recorded in the Records of Sui Shu compiled by Wei Zhi and others in the Tang Dynasty: "At the end of the Song Dynasty, Nanxu people were engaged in the secret method worshipped by their ancestors. Take the diameter of one hundred million circles as ten feet, and the circumference abundance as three feet, one foot, four inches, one minute, five minutes, nine minutes, two seconds and seven seconds; Count three feet, one foot, four inches, one point, five points, nine points, two seconds and six seconds, and the positive number is between the profit limit and the profit limit. Density: circle diameter 1 13, circumference 355. Contract rate: circle diameter 7, Tuesday 12. "

The "open" here is pioneering, and the circle diameter of 10 foot is taken as 10 foot, and the circle diameter of10 foot is divided into 100 million equal parts: "abundance" is the residual approximation of the circle, and "number" is the insufficient approximation; "Positive number" is the correct value, that is, the true value.

The above record contains three meanings:

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