Work tasks: on-the-job internship: enable students to fully fulfill all responsibilities of their internship positions, independent, with greatChallenge plays a great role in the exercise of students' ability. Graduation internship: to the internship site to participate in some practical work, through the comprehensive use of all professional knowledge and related basic knowledge to solve professional and technical problems.
There are significant differences between post internship and general graduation internship in many aspects. First of all, in terms of work load and exercise opportunities, the internship requires students to devote themselves to the internship position and assume all responsibilities, which is a very challenging process and is crucial to the improvement of personal ability. In contrast, graduation internships involve students in practical work, applying professional knowledge to solve practical problems, but on the exercise sideThe emphasis is more on the combination of theory and practice.
Concept post internship is a way for schools to arrange students to practice in school. Non-basic education schools usually arrange students to do internship before graduation, including centralized internship, decentralized internship, and on-the-job internship.
The composition and structure of C60 have been proved by mass spectrometry, X-ray analysis and other experiments. In addition, many molecules similar to C60, such as C70, have also been discovered.
[Answer] : In 1985, the British scientist H.W. Kroto and the American scientists R.F. Krol and R.E.Malley and others used laser gasification experiments to discover C60.Since then, C50, C70, C240 and even C540 have been discovered. Among fullerenes, C60 has been studied most deeply, and its research field not only involves various branches of chemistry, but also involves life science, materials science and solid state physics.
The discovery of C60 originally began in the field of astronomy research, and then through experimental preparation. The discovery of C60 began in the field of astronomy, where scientists first became interested in the widespread distribution of carbon dust among stars.
Nobel Prize for the discovery of fullerenes. 2010 University of Western Ontario ScienceScientists have found evidence of C60 in a cosmic nebula 6,500 light-years away, using the Spitzer Space Telescope to detect a specific signal of C60. On August 25, 2014, scientists had long envisioned using other elements to construct buckyballs with the same structure, and this idea became a reality, researchers completed the first buckyball composed of boron atoms. In recent years, scientists have found that in addition to diamond and graphite, there are some new carbon in the form of simple substances. Among them, C60 molecule was discovered earlier and has made important progress in research. C60 pointsIntroduction to the history of Lighting In ancient times, man used natural light for illumination. Since humans learned to drill wood to make fire, there have been torches, animal oil lamps, plant oil lamps, candles, kerosene lamps lighting tools. More than 100 years ago, the British invented the gas lamp, which made the human lighting method a big step forward. On October 22, 1879, Edison lit the first truly widely used electric lamp.
Origin of lighting The earliest lighting tools used by humans were torches and torches. In ancient times, torches and torches were the main means of lighting. The torch isA tool used to light wood after being lit, the torch is based on the torch with a container to protect the flame and prevent it from going out. With the passage of time, people began to use oil lamps, candles and gas lamps and other lighting tools.
At the end of the century, Edison invented the electric lamp, which has since rewritten the history of human lighting, and human beings have moved to the era of electric lighting. Electric light bulb (incandescent lamp) : The current in the wire enters the very fine wire, the wire will produce high heat, hot to a certain extent will emit light, which is the earliest electric lamp, and is still widely used today.
Chinese light bulbs usedThe history began in July 1882, when China's first electric lamp was lit on Nanjing Road in Shanghai, marking the beginning of the era of electric lighting in China. "New News" reported the incident, titled "Shanghai road administration trial lights." As early as 1861, the British consul's residence in Wuhan took the lead in installing electric lights to provide lighting services for the British rental sector, creating a precedent for the use of electric lights in Wuhan.
The discovery of fire is an important turning point in human history, and the birth of torches and animal oil lamps symbolizes the initial germination of lighting technology. With the rolling wheels of history, gas lamps in the 18th century, kerosene lamps in the 19th century, and then the Warring StatesSilver head humanoid lamp, Western Han dragon lamp, the unique charm of Chinese lighting art, not only practical, but also carries profound cultural connotation.
In
, the British Joseph Swan also made carbon filament electric lamps, but he failed to obtain a good vacuum environment to keep carbon filament working for a long time. In 1878, the development of vacuum technology in the United Kingdom to meet the needs of the degree, he invented the vacuum with carbon wire electricity bulb, and obtained a British patent. Swan's own house was the first private home in Britain to be lit by electricity.