Maria Skolodovskaya, the famous Marie Curie, is known as the "Mother of Radium." She was born on November 7, 1867 in Warsaw, the capital of Poland under the rule of the Russian Tsarist invaders. Her father was a professor of physics at Warsaw University of Higher Education, which made her interested in scientific experiments from an early age.
In 1891, she went to Paris to continue her studies and obtained two master's degrees. After completing her studies, she planned to return to her homeland to serve the enslaved Polish people, but her acquaintance with the young French physicist Pierre Curie changed her plans. In 1895, she married Pierre, and in 1897 they gave birth to a daughter, a future Nobel Prize winner.
Marie Curie noticed the research work of French physicist Becquerel. After R?ntgen discovered X-rays, Becquerel discovered another "uranium ray" when examining a rare mineral "uranium salt". Friends called it Becquerel rays.
The rays discovered by Becquerel aroused great interest in Marie Curie. Where does the power emitted by the rays come from? Marie Curie saw that no one in any laboratory in Europe had conducted in-depth research on uranium rays at that time, so she decided to break into this field.
After Pierre’s repeated requests, the principal of the Physical and Chemistry School allowed Madame Curie to use a humid cabin for physical and chemical experiments. At a room temperature of 6 degrees Celsius, she completely devoted herself to the research of uranium salts.
Marie Curie received a strict higher education in chemistry. When she was studying uranium salt ore, she thought that there was no reason to prove that uranium is the only chemical element that can emit rays. She measured the elements arranged one by one according to Mendeleev's periodic law of elements, and soon discovered that another compound of the thorium element could also automatically emit rays, which were similar to uranium rays and had similar intensity. Marie Curie realized that this phenomenon was by no means just a characteristic of uranium and that it had to be given a new name. Marie Curie proposed calling it "radioactive". Uranium, thorium and other substances with this special "radiating" function are called "radioactive elements".
One day, Marie Curie thought, are minerals radioactive? With Pierre's help, she spent several days measuring all the minerals she could collect. She discovered that a type of pitchblende was much more radioactive than expected.
After careful study, Marie Curie had to admit that the uranium and thorium content in these pitchblende minerals could never explain the intensity of the radioactivity she observed.
Where does this abnormal and excessive radioactivity come from? There can be only one explanation: these asphalt minerals contain small amounts of a new element that is much more radioactive than uranium and thorium. In her previous experiments, Marie Curie had examined all known elements at that time. Madame Curie concluded that this was a new element unknown to humans, and she wanted to find it!
Madame Curie’s discovery attracted Pierre’s attention, and the Curies marched into unknown elements together. In the damp studio, after the Curies worked together to tackle the problem, in July 1898, they announced the discovery of this new element, which was 400 times more radioactive than pure uranium. In order to commemorate Marie Curie's home country - Poland, the new element was named polonium (meaning Poland).
In December 1898, the Curies announced based on experimental facts that they had discovered a second radioactive element. This new element was more radioactive than polonium. They named this new element "radium". However, no one could confirm their discovery at that time, because according to the tradition of the chemical community, when a scientist announces that he has discovered a new element, he must obtain the physical object and accurately measure its atomic weight. However, there was no atomic weight of the needle or radium in Marie Curie's report, and there was no sample of radium on hand.
The Curies decided to prove it with physical objects. At that time, pitchblende, which contained polonium and radium, was a very expensive mineral mainly produced in the St. Joachim Star mine in Bohemia. People refined this mineral and extracted it to make colored glass. Uranium salts used. For the Curies, who live very poor lives, how can they have the money to pay for the necessary expenses for this work? Their wisdom supplemented their financial resources. They predicted that after uranium was proposed, the new radioactive elements contained in the minerals must still exist, so they would definitely be found in the mineral residues after refining uranium salts. After countless twists and turns, the Austrian government decided to donate a ton of waste slag to the Curies and promised that if they needed a large amount of slag in the future, it could be supplied under the most favorable conditions.
The conditions in the Curies' laboratory were extremely poor. In summer, because the ceiling was made of glass, the inside was scorched like an oven by the sun; in winter, it was so cold that people almost froze. The Curies overcame unimaginable difficulties and worked hard to refine radium. Marie Curie immediately put into extraction experiments. She put more than 20 kilograms of waste slag into a smelting pot to melt it at a time. She stirred the boiling material with a thick iron rod for several hours, and then extracted only one million parts from it. one of the trace substances.
They worked from 1898 to 1902. After tens of thousands of refinings and processing dozens of tons of ore residues, they finally obtained 0.1 grams of radium salt, and their atomic weight was determined to be 225. .
Radium was announced!
The Curies confirmed the existence of radium element, which made the whole world pay attention to the phenomenon of radioactivity. The discovery of radium sparked a real revolution in science.
Marie Curie completed her doctoral thesis on the topic (Study of Radioactive Substances). In 1903, Marie Curie received a doctorate in physics from the University of Paris. In the same year, the Curies and Becquerel won the Nobel Prize in Physics.
Following the discovery of radium, other new radioactive elements such as actinium were also discovered. Exploring the laws of radioactive phenomena and the nature of radioactivity has become a primary research topic in the scientific community.
Domestic: Xi'an's Terracotta Warriors, Mausoleum of Qin Shihuang, Big Wild Goose Pagoda, Forest of Steles! West Lake in Hangzhou! The Temple of Heaven in the Forbidden City in Beijing, the Ming Tombs, and the Western Tombs of the Qing Dynasty! Nanjing Sun Yat-sen Mausoleum! What about Shaolin Temple, Mount Tai, Mount Lu, and Mount Wutai! Confucius Temple in Shandong! The Giant Buddha in Leshan, Sichuan! Potala Palace in Tibet! White Horse Temple and Yungang Grottoes in Luoyang! Mogao Grottoes in Dunhuang, Gansu! Great Wall! (There are too many in our country, so I just found some)
Italy: Leaning Tower of Pisa, Piazza San Marco in Venice, Colosseum, Pantheon in Rome and Piazza Venezia, and The country within the city of Rome - Vatican City, this pocket-sized country is full of scenic spots and historic sites! France: Paris’ Arc de Triomphe, Eiffel Tower, Louvre, Notre Dame, Panthéon, Place de la Concorde (all in Paris) and the lavender in Provence is also worth seeing!
Germany: Berlin Brandenburg Gate, White Swan Castle, Lake Constance, Cologne Cathedral, the source of the Danube River.
Russia: Moscow’s Red Square and Kremlin, Vasily’s Cathedral, St. Petersburg’s Winter Palace and Summer Palace, Peter and Paul Cathedral, and Sochi and Kazan are two great cities!
Spain: There are no particularly famous monuments, except for its own royal palace and some relics from ancient Rome. However, Spain’s coastline has good scenery, and the beach is made of roasted dodder and rose mold?
< p>South Asia: India’s Taj Mahal, Ellora Caves Temple, Mahabalipuram Giant Relief, Sikh Golden Temple, Khajuraho Temple Complex, Sun Temple (the above is India). Pakistan: Sikh Fort, Faisal Mosque.Egypt: Pyramids (the most famous of which is the Pyramid of Khufu), Sphinx, Khan Khalili Market, Karnak Temple, Luxor Temple, Colossi of Mennon, Valley of the Kings , Ramesses III’s Burial Hall, Abu Simbel Temple.
I’m tired of writing, so I’ll give you a general introduction. The American Mayans also had pyramids, and there are also the forgotten cities of Machuli located on the top of the mountains in the Andes. There are also meteorites in the Muslim resorts of Mecca and Jerusalem. It is said that Mohamed received the will from Allah from this meteorite. There is also the capital of the ancient Khmer dynasty in the jungles of Cambodia, which was only discovered in modern times.
In addition, natural scenery such as the Niagara Falls in the United States and the Alps in Europe can also be considered scenic spots. There are really too many!
Masterpiece 1 "The Analects"/1 Masterpiece 2 "Romance of the Three Kingdoms"/10 Masterpiece 3 "Hamlet"/23 Masterpiece 4 "The Scream"/33 Masterpiece 5 "Talking about Beauty"/44 Masterpiece 6 "The Origin of Species" "/52 Masterpieces 7 "A Dream of Red Mansions"/59 Masterpieces 8 "The Old Man and the Sea"/70 Masterpieces 9 "Midnight"/82 Masterpieces 10 "Thunderstorm"/93 Masterpieces 11 "Resurrection"/106 Masterpieces 12 "The City Besieged"/121 Masters 13 " "Les Misérables"/136 Masterpieces 14 "In Search of Lost Time"/143 Masterpieces 15 "Home"/150 Masterpieces 16 "Don Quixote"/161 Masterpieces 17 "Water Margin"/175 Masterpieces 18 "The Catcher in the Rye"/ 185 Masterpieces 19 "Notre Dame de Paris"/193 Masterpieces 20 "Journey to the West"/203 Masterpieces 21 "How Steel Was Tempered"/211 Masterpieces 22 "Crime and Punishment"/219 Masterpieces 23 "The Goddess"/227 Masterpieces 24 "Lu Robinson Crusoe"/237 Masterpiece 25 "The Interpretation of Dreams"/246 Masterpiece 26 "The Pickwick Papers"/251 Masterpiece 27 "The Red and the Black"/260 Masterpiece 28 "Goethe's Conversations"/274 Masterpiece 29 "Natural Philosophy" "Principles of Mathematics"/286 Masterpieces 30 "The Quiet Don"/291 Masterpieces 31 "The Great Gatsby"/297 Masterpieces 32 "A Farewell to Arms"/306 Masterpieces 33 "All Quiet on the Western Front"/311 Masterpieces 34 " Montaigne's Essays"/317 Masterpieces 35 "The Unbearable Lightness of Being"/323 Masterpieces 36 "One Hundred Years of Solitude"/329 Masterpieces 37 "Doctor Zhivago"/338 Masterpieces 38 "Catch-22"/350 Famous Works 39 "The Metamorphosis"/359 Famous Works 40 "Eugenie Grandet"/367 Famous Works 41 "Uncle Tom's Cabin"/380 Europe did not begin to eliminate the intellectual crisis until 1660, but the basic work to solve the crisis had already begun. Puller, Galileo, Bacon and Descartes were ready. As mentioned above, Kepler and Galileo perfected and promoted the heliocentric theory, triggered the Copernican Revolution, and overturned the medieval worldview. The main achievements of Bacon and Descartes did not lie in their original scientific discoveries, but in the spread of new ideas about academics and the nature of the universe, namely Baconism and Cartesianism.
Francis Bacon (1561-1626 AD) was born into an aristocratic family in England. His father was Lord Privy Seal of England. Bacon was keen on official career and for a time he served as Lord Chancellor of England - the highest office his class could hold. However, he was soon thrown into prison on charges of corruption and bribery and was dismissed from all positions. Although he was released soon, from then on, he concentrated on his research work and no longer interfered with officialdom.
Bacon was a very influential philosopher of science. He believed that science can only develop after it has completely separated itself from the inherent errors of the past and established several progressive stages. What Bacon meant by this was that science should be strictly based on empirical knowledge (knowledge acquired entirely through the senses) and conducted research by means of "induction" (obtaining truth through specific observations of universals). He advocated the collaborative advancement of knowledge through meticulous recording of empirical experiments. Different from the boring reasoning of the past, the same scientific research and observation derive useful knowledge, which ultimately improves the destiny of mankind.
Bacon believed that as long as he followed his procedures, scientific truth could be derived naturally. This was taking things too easy. And although he valued experience, he had no concept of experimental methods and ignored the role of mathematics. He himself had no scientific achievements, and he had no positive evaluation of Copernicus, Galileo and others. However, he advocated new science and strongly inspired many people who were interested in scientific research in the 17th century; he proposed a methodology for organizing scientific research, and his vision became a reality when the Royal Society was established. People call him this The founder of a career. Therefore, as far as modern science is concerned, Bacon's contribution lies in advocating the idea of ??new science and purpose.
The Frenchman Rene Descartes (569 AD - 1650), a contemporary of Bacon, agreed with Bacon on two points: all old knowledge should be abandoned; Whether it has value or not depends on whether it has practical value. But their attitudes towards science were very different, because Bacon was an empiricist, while Descartes was a rationalist and an outstanding mathematician. Descartes took reason as the starting point of the entire philosophical activity and reconstructed a worldview that was largely based on speculation and was different from the ancient Greeks in almost every aspect.
Descartes believed that the simplest elements in natural philosophy are extension and motion, which are the essential properties of matter. Space is extension, it is matter. Space has no special direction such as up and down, nor is there any hierarchical order in the center of the universe and its surroundings. Space is always extended, and the extension of space is matter. This is the concept of isotropic infinite space that is the premise of modern physics. Descartes drew the second conclusion from simple elements: all natural phenomena can be reduced to the relative motion between the parts of an object. According to this view, the laws of motion are the basis of all knowledge about nature, and any phenomenon can be explained by the combination of small parts and the combination of motion. Descartes planned to reconstruct the entire universe from the results he discovered and according to his own methods. He believed that the entire space of the universe was filled with vortex motions of media. In this vortex motion, coarser material blocks gather everywhere to form celestial bodies. These celestial bodies are pushed by the vortex motion of the surrounding media. Descartes then goes on to treat terrestrial phenomena - including living things and non-living things - It is explained in the same mechanistic way, that is, in terms of the combination and motion of small pieces of matter.
Compared with today's natural science, Descartes's mechanical explanation of the universe certainly cannot be sustained. Even at the time, it was opposed by many people. However, Desire's views on nature, that is, nature is a combination of elements, and the behavior of elements is determined entirely based on mechanics, as well as the mathematical methods he advocated, have pointed out the way forward for modern science, especially physics.
In the second half of the 17th century, the mechanistic particle theory of nature reached its heyday. In the early 17th century, Gassendi (1592-1665 AD) resurrected atomism. He regarded atoms and their movements as created by God, which washed away the atheistic reputation of atomism and made it accepted by people. He believed that atoms were irreducible and moved in a vacuum, which was in sharp contradiction with Descartes, who did not admit vacuum. Descartes strongly objected that the vacuum and the atoms were indivisible. However, the two can actually go hand in hand. Atoms can be thought of as tiny parts that divide Descartes' medium-filled universe. Under the influence of the two, Boyle put forward his own particle theory, integrating the culmination of the particle theory of nature. He called his theory particle philosophy. The content is:
1. There is a universal substance that is possessed by all objects. It is an extended, divisible, and inaccessible entity.
2. The variety of objects arises from the motion of this substance.
3. Since moving matter is divided according to motion, "minimum natural objects" that perform various motions and have certain shapes and sizes are produced.
Four The smallest natural objects gather together to form particles. Such particles have a certain shape and size and can be moving or stationary. All objects that can be perceived are composed of a collection of such particles.
5. The interaction between particles is caused by the collision, combination and other reasons caused by the movement, shape and size of the particles. Particles come in various shapes such as hook-shaped and pointed shapes.
6 The diversity of the world is produced by the effects of particles on our sense organs.
Particle theory is the dominant mechanistic view of nature in modern science.
Through the efforts of Bacon, Descartes and Boyle, the conceptual framework required by modern science was formed, namely: the independent existence of empirical things, the infinite extension of isotropic space, heaven and earth The elimination of distinctions, the possibility of combining science and practice, the emphasis on mathematical methods, and above all this a mechanistic view of nature. However, a fundamental category must also be added, which is the law of nature. Nature exists independently. Natural phenomena generally obey laws without exception and change in an orderly manner.
Only when this concept begins to appear in people's minds can it be possible to establish science with the purpose of exploring the laws of nature.
The laws of nature have not existed since ancient times. Ancient Greek philosophers, whether they were atomists or Plato and Aristotle, even though they had the concept of "necessity", they did not realize that this was the law followed by nature. People in the Middle Ages valued irregular things as manifestations of divine power, but did not care about the rules themselves. In scholastic philosophy, entities and attributes discuss nature based on matter and form, and lack the category of law. Bacon, Gilbert, and even Galileo did not clearly and consciously form the concept of "natural laws". It was not until Descartes that the concept of laws was clearly established in nature.
The above constitutes the theoretical framework of modern physics. Subsequently, experimental methods were also established. Through purposeful and precise experiments, people filled in substantial content within the theoretical framework and promoted the development of physics. Newton, Torricelli, Galileo, etc. were all outstanding experimentalists.
The establishment of experimental methods stimulated scientific research and promoted the creation of social organizations to carry out research work. At the same time, mathematics, as an important tool, is also valued. The mathematics at that time was inherited from ancient Greek mathematics. Ancient Greek mathematics was geometrical and not conducive to the application of physics. For this reason, innovation in mathematics is necessary and inevitable. At that time, the introduction of the Indian counting method and the popularization of written calculation played a great role in promoting the innovation of mathematics. Until the establishment of symbolic algebra, geometricism was shattered, mathematics was liberated from graphics, and the foundation for calculus was laid.
Before 1671, Newton completed calculus. A few years later, Leibniz also independently discovered calculus. The creation of calculus made mathematics a powerful weapon for solving physical problems.
A decisive factor in the establishment of modern physics was the law of universal gravitation proposed by the British Isaac Newton (1642-1727 AD). For about a hundred years after Bacon and Descartes, the scientific community in England was Baconian and the scientific community in France was Cartesian. That is to say, the British mainly focused on conducting empirical experiments in various fields of natural science and promoted the progress of specific science; the French tended to emphasize mathematics and philosophical theories. But the distinction between the two factions disappeared with Newton. Although Newton was unremarkable in life—tight-lipped, cautious, and vindictive—he was a master of Baconism and Cartesianism. He followed Bacon's principles of empiricism and conducted a large number of successful experiments; at the same time, he followed Descartes and introduced mathematics into physics. In 1687, he published his epoch-making masterpiece "Mathematical Foundations of Natural Philosophy", which convincingly solved two major scientific problems at that time: first, under what action the heavy earth is in motion; second, why do things on the earth move Objects fall toward the center of the Earth while planets remain in orbit. Newton established a new mechanical system and proposed a new view of space and time. From this, modern physics was established.