This year, we continued to expand the boundaries of knowledge
2021 has come to an end, and the past year has been a year of record highs and harvests in the science and technology industry.
This year coincided with the 100th anniversary of the Communist Party of China, and my country's scientific and technological circles made many important breakthroughs.
Significant progress has been made in quantum computing, making my country the only country that realizes the superiority of quantum computing in two physical systems; "China Sky Eye" is officially opened to the world, showing its demeanor as a big country; successfully realizing carbon dioxide synthetic starch to provide for the future of mankind New possibilities...
This year is a year in which the scientific and technological workers keep walking, they are persevering in pursuing the truth of science, constantly refreshing the new heights that mankind can reach.
The scientific and technological world will surely set sail again in the east wind of the times and head forward towards a more colorful future.
Retrieve the rice "ancestor" gene
Help cultivate better rice varieties
Rapidly domesticate allotetraploid wild rice from scratch, take advantage of polyploidy, retrieve some excellent genes that have been lost in current cultivated rice, and cultivate new rice crops with higher yields and stronger environmental adaptability-Chinese Academy of Sciences Seed Innovation This breakthrough progress made by the Li Jiayang team and collaborators of the Institute and Institute of Genetics and Developmental Biology was published in the internationally renowned academic journal Cell on February 4.
Polyploidization is an important mechanism of plant evolution.
The cultivated rice we grow today has been artificially domesticated for thousands of years, and its agronomic characteristics have been continuously improved, but at the same time a large amount of genetic diversity has been lost, resulting in the lack of dominant gene resources.
Compared with diploids, allotetraploids have two more chromosomes. Allotetraploid wild rice has the advantages of large biomass, self-contained hybrids, and strong environmental adaptability.
But its non-domesticated characteristics also prevent it from being directly used in agricultural production.
Starting from the tetraploid wild rice with better comprehensive performance, the Li Jiayang team used modern genome editing technology to "repeat" the history of rice domestication from thousands to tens of thousands of years in a short period of time, and avoided partial gene loss. The first design and completion The framework of the rapid de novo domestication of allotetraploid wild rice is expected to produce new rice crops with high yields and strong environmental adaptability.
The research team broke through technical bottlenecks such as genome analysis, high-efficiency genetic transformation, and high-efficiency genome editing, and annotated a series of domesticated genes and genes for important agronomic traits in the genome of allotetraploid high-stalk wild rice, and successfully created reduced shattering and long awns. Variety of genome-edited allotetraploid wild rice materials that have become shorter, lower plant height, longer grain length, thicker stalks, and shortened heading time to varying degrees.
"Chapter 9" "Zu Chongzhi" Joshin
Achieve quantum superiority in two physical systems
The research and development of quantum computers with practical value has always been one of the most important development goals in the field of quantum computing, and it is also the focus of competition among countries.
In the past year, my country has made many major advances in the field of quantum computer research and development.
On February 27, the international authoritative journal "Science Progress" published results. A new programmable silicon-based optical quantum computing chip developed by researchers from the National University of Defense Technology, the Academy of Military Sciences, Sun Yat-sen University and other institutions has realized a variety of graph theory problems. The quantum algorithm for solving the problem is expected to be applied in fields such as big data processing in the future.
On May 7, "Science" magazine published the research results of Pan Jianwei's team at the University of Science and Technology of China. It successfully developed the quantum computing prototype "Zuchongzhi", which manipulated 62 superconducting qubits, and realized on this basis Programmable two-dimensional quantum walk.
This achievement lays a technical foundation for realizing quantum superiority in superconducting quantum systems and for subsequent research on quantum computing with great practical value.
At the end of October, Pan Jianwei's team further developed a 66-bit programmable superconducting quantum computing prototype "Zuchongzhi 2.0", which achieved the superiority of quantum computing on random line sampling tasks, and the difficulty of the completed tasks was higher than that of Google's "Platanus" in 2019. It is 2-3 orders of magnitude higher.
At the same time, Pan Jianwei’s team’s upgraded version of "Nine Chapters 2.0" has also greatly improved its quantum advantage. For the Gaussian Bose sampling problem, the task that can be completed in one minute in the "Nine Chapters" one year ago is the most powerful in the world. The supercomputer takes hundreds of millions of years; the time spent on the supercomputer will increase by tens of billions of times for the tasks completed in one minute in "Nine Chapters 2.0".
And "Nine Chapters 2.0" also has some programmable capabilities.
The emergence of "Nine Chapters 2.0" and "Zu Chongzhi 2.0" makes my country the only country that has achieved the superiority of quantum computing in the two physical systems.
"China Sky Eye" welcomes scientists from all over the world
Observation applications will be collected at the end of March
In line with the principle of open sky, the 500-meter spherical radio telescope (FAST), a major national scientific and technological infrastructure known as the "China Sky Eye", has issued an invitation to astronomers around the world from 0:00 on March 31, 2021, Beijing time. Observation application, all foreign application projects will participate in the review.
The observation time starts in August of this year.
China SkyEye is located in Dawotai, Pingtang County, Qiannan Prefecture, Guizhou Province. It was completed in 2016 and is the world's largest single-aperture radio telescope with independent intellectual property rights.
Radio telescopes are the same as optical telescopes. The larger the aperture, the more electromagnetic waves it receives, the higher its sensitivity and the stronger its detection capability.
In this way, China's celestial eye can monitor the weak radio signals in the universe.
Since the start of operation through national acceptance, China's SkyEye facility has been operating stably and reliably. The number of pulsars discovered has reached more than 500, and major breakthroughs have been made in research fields such as rapid radio bursts.
The development and construction of China Sky Eye not only reflects my country's independent innovation capability, but also promotes the development of many high-tech fields in my country, such as antenna manufacturing technology, microwave electronic technology, parallel robots, large-scale structural engineering, and high-precision dynamic measurement within kilometers.
Wu Xiangping, academician of the Chinese Academy of Sciences and director of the FAST Scientific Committee, said that FAST is open to use around the world, demonstrating the concept of full cooperation and the practice of the concept of a community with a shared future for mankind.
Use liquid helium to create a -271℃ world
Large-scale cryogenic refrigeration equipment "Made in China"
On April 15, the national major scientific research equipment development project "Development of large-scale cryogenic refrigeration system from liquid helium to superfluid helium temperature zone" undertaken by the Technical Institute of Physics and Chemistry of the Chinese Academy of Sciences (hereinafter referred to as the Institute of Physics and Chemistry of the Chinese Academy of Sciences) passed the acceptance and achievement appraisal, and the project achievement appraisal The expert group believes that the overall technology of the project has reached the international advanced level.
This indicates that my country has the ability to develop large-scale cryogenic refrigeration equipment with liquid helium temperature (-269°C) kilowatts and superfluid helium temperature (-271°C) hundreds of watts.
Liquid helium is an "artifact" for manufacturing ultra-low temperature.
With the rapid development of the social economy, my country has become a major user of large-scale cryogenic refrigeration equipment.
However, due to the lack of large-scale cryogenic refrigeration systems, key sub-equipment and integrated technology, my country's large-scale cryogenic refrigeration equipment has been monopolized by foreign countries for a long time, and its import dependence is high.
In December 2015, the Institute of Physics and Chemistry of the Chinese Academy of Sciences started the development of large-scale cryogenic refrigeration equipment from liquid helium to superfluid helium temperature range.
On the basis of decades of low-temperature technology accumulation, after five years of arduous research and adherence to the road of independent innovation, the large-scale helium refrigerator with advanced technical indicators was finally successfully developed.
Light storage time up to 1 hour
An important step has been taken for the vector USB flash drive
In April, Li Chuanfeng and Zhou Zongquan of the Guo Guangcan team of the University of Science and Technology of China increased the optical storage time to 1 hour, which greatly refreshed the 1-minute optical storage world record created by the German team in 2013, and took an important step towards the realization of a quantum USB flash drive.
The results were published in the authoritative academic journal "Nature Communications" in late April.
Light has become the basic carrier of modern information transmission.
The speed of light is as high as 300,000 kilometers per second, and "reducing" the speed of light and even allowing the light to "stay" is the goal of the international academic community.
The storage of light is particularly important in the field of quantum communication. By storing photons in ultra-long-life quantum memory, that is, a quantum USB disk, the quantum information can be transmitted directly by transporting the quantum USB disk.
Considering the speed of transportation such as airplanes and high-speed rails, the optical storage time of a quantum U disk needs to be at least on the order of hours.
The research groups of Li Chuanfeng and Zhou Zongquan made their own optical Raman heterodyne detection nuclear magnetic resonance spectrometer in 2015. Relying on this instrument, it accurately described the complete Hamiltonian of the optical transition of the europium-doped yttrium silicate crystal, and theoretically predicted the first order. The Zeeman effect is the energy level structure under the ZEFOZ magnetic field.
In the future, relying on more mature quantum USB disks, mankind is expected to realize quantum information transmission based on classical transportation tools, thereby establishing a new quantum channel.
"Artificial Sun" breaks the world record
Achieve a repeatable combustion of 120 million ℃ for 101 seconds
On May 28th, good news came from the Hefei Institute of Material Science, Chinese Academy of Sciences. The fully superconducting Tokamak Nuclear Fusion Experimental Device (EAST), known as the "artificial sun", achieved a new breakthrough and successfully achieved a repeatable 120 million degrees Celsius 101 20 seconds of plasma operation at 160 million degrees Celsius and 160 million degrees Celsius, setting a new world record for the operation of the Tokamak experimental device, and taking an important step towards the application of nuclear fusion energy.
The light and heat on which all things grow on the earth originate from the energy released by the sun's nuclear fusion reaction.
The fuel deuterium that supports this fusion reaction is extremely abundant on earth, enough for humans to use for tens of billions of years.
If deuterium can be used to create an "artificial sun" to generate electricity, mankind is expected to completely realize energy freedom.
But the creation of an "artificial sun" faces a prominent practical problem: what container is used to carry nuclear fusion?
The ion temperature of the plasma needs to be over 100 million ℃ under artificially controlled conditions.
At present, the melting temperature of tungsten, the most heat-resistant metal material on earth, is more than 3000°C.
This means that it is necessary to create a device that can carry large current, strong magnetic field, ultra-high temperature, ultra-low temperature, high vacuum, high insulation and other complex environments at the same time, which places extremely high requirements on process design and materials.
In order to meet the requirements of the fusion experimental device, the scientists of the EAST team independently innovated, independently designed and developed most of the key technologies with independent intellectual property rights, and creatively completed the overall engineering design of the EAST device host.
The world's new generation of all-superconducting Tokamak nuclear fusion experimental device was first completed in China and officially put into operation, providing an experimental research platform for the future use and development of clean energy.
Earth simulation device activated
See the past, present, and future of the earth clearly
On June 23, the "Earth System Numerical Simulation Device", a major national scientific and technological infrastructure, was completed and put into use in Beijing Huairou Science City.
This is the first large-scale earth system simulation scientific device with independent intellectual property rights successfully developed by my country.
Earth system simulation device, also known as earth simulation laboratory, is to carry out numerical simulation of the earth system, that is, based on the observation data of the earth system, using the laws describing the physics, chemistry and life process of the earth system and its evolution to be carried out on a supercomputer Large-scale scientific computing.
As a result, scientists can reproduce the past of the earth, simulate the present of the earth, and predict the future of the earth.
The overall performance of the newly completed earth simulation laboratory is comparable to the international advanced level. It is the first in my country with independent intellectual property rights. It is based on the numerical simulation software of each layer of the earth system, and is designed in collaboration with hardware and software, scale and comprehensive technical level. A dedicated earth system numerical simulation device at the forefront of the world.
It has the ability to simulate the various layers of the earth's surface and can more comprehensively consider the various processes of the earth system.
Especially in the most urgent field of climate change and carbon neutrality, the system can fully focus on global ecological and biogeochemical processes and their interaction with the climate system, and on this basis establish an "ecology-temperature- The clear relationship between carbon dioxide concentration and carbon emissions" provides strong simulation support for greenhouse gas accounting and future warming predictions, and helps achieve carbon peaks and carbon neutrality goals.
And it will also provide a basis for my country's future negotiations in the field of climate and environment, and enhance my country's international voice.
"Ice Fiber" comes out
Can be flexibly bent and efficiently guide light
On July 9th, the authoritative academic journal "Science" published the results showed that the team of Professor Tong Limin from the School of Optoelectronic Science and Engineering of Zhejiang University and the researchers from the Center for Cross Mechanics of Zhejiang University and the University of California, Berkeley, in the -50 ℃ environment, The high-quality ice single crystal micro-nano fiber was prepared.
It can not only bend flexibly, but also transmit light with low loss, which is similar to glass fiber in performance.
As a functional structure that confines and transmits light freely, optical fiber is one of the most effective tools for light field manipulation.
Silicon oxide (quartz sand), the main component of conventional glass optical fibers, is one of the most abundant substances in the earth's crust.
But in fact, in the earth and many extraterrestrial bodies, the more common substance than quartz sand is ice or liquid water.
Therefore, the use of ice to prepare optical fibers has broad application prospects.
In this research, Tong Limin’s team built a growth device by itself. Based on a large number of experiments, the existing electric field-induced ice crystal preparation method was improved. In a low-temperature and high-voltage electric field, supplemented by a certain humidity condition, the water molecules move toward The direction of the electric field changes its disordered state of motion, thereby inducing single crystal growth.
Finally, in an environment of -50°C, an ice single crystal micro-nano fiber with a diameter of 800 nanometers to 10 microns was successfully fabricated.
In addition, the team also used the newly invented low-temperature micro-nano manipulation and transfer technology to obtain an elastic strain of 10.9% for the ice micro-nano fiber in an environment of -150°C, which is close to the theoretical elastic limit of ice.
Tong Limin believes that the results of this research will expand people’s perception of ice, inspire people to carry out research on ice-based optical fiber in optical transmission, optical sensing, ice physics, etc., as well as the development of micro-nano-scale ice suitable for special environments. Based technology.
"Throw away" photosynthetic synthetic starch
Save resources and improve production efficiency
On September 23, the Chinese Academy of Sciences announced major achievements.
Researchers from the Tianjin Institute of Industrial Biotechnology of the Institute proposed a subversive starch preparation method that does not rely on plant photosynthesis, and uses carbon dioxide and hydrogen generated by electrolysis as raw materials to successfully produce starch. The de novo synthesis of starch makes it possible to transform starch production from a traditional agricultural planting model to an industrial workshop production model.
Related research results were published online in the journal Science on September 24.
Starch is mainly synthesized by green plants by fixing carbon dioxide through photosynthesis.
In crops such as corn, the conversion of carbon dioxide into starch involves more than 60 steps of metabolic reactions and complex physiological regulation, and the theoretical utilization efficiency of solar energy does not exceed 2%.
The planting of crops requires a cycle of several months, using a large amount of land, fresh water, fertilizer and other resources.
In order to improve production efficiency, researchers from the Tianjin Institute of Industrial Biology, Chinese Academy of Sciences designed a new way of unnatural carbon dioxide fixation and artificial starch synthesis with an 11-step main reaction from the beginning, achieving the full synthesis of carbon dioxide to starch molecules in the laboratory for the first time.
The starch synthesis rate of this artificial route is 8.5 times that of corn starch.
And under the condition of sufficient energy supply, according to current technical parameters, theoretically, the annual starch output of a 1 cubic meter bioreactor is equivalent to the average annual output of corn planted on 5 acres of land in my country.
Prove the core conjecture of Keller's geometry
Solve the "unsettled case" in mathematics for more than 60 years
In early November, Professor Chen Xiuxiong, founding director of the Center for Geometric Physics, University of Science and Technology of China, and collaborator Cheng Jingrui achieved milestone results in the field of partial differential equations and complex geometry. They solved a fourth-order fully nonlinear elliptic equation and successfully proved the mandatory conjecture. And the geodesic stability conjecture, two core conjectures that have been unresolved in the international mathematics community for more than 60 years, have solved a number of well-known problems related to the constant scalar curvature measurement and the Calabi extremum measurement on the Keller manifold.
Two papers were published in the internationally renowned journal "Journal of the American Mathematical Society".
The existence of constant scalar curvature measures on Keller's manifold has been one of the core problems in geometry over the past 60 years.
Regarding its existence, there are three well-known conjectures—stability conjecture, mandatory conjecture, and geodetic stability conjecture.
After nearly 20 years of work by many famous mathematicians, the necessity of the compulsory conjecture and geodetic stability conjecture has become completely clear, but the proof of its adequacy has been considered out of reach before.
Solving a class of fourth-order completely nonlinear elliptic equations can prove the existence of constant scalar curvature measures.
The work of Chen Xiuxiong and Cheng Jingrui is precisely under the assumption of K-energy compulsion or geodetic stability to prove the existence of solutions of this type of equation.
They not only found the solutions of equations, but also established a set of methods to study such equations systematically, providing a new tool for exploring the unknown world of mathematics.
In addition, they also gave a proof of the stability conjecture on ring symmetric Keller manifolds, extended Donaldson's classic theorem on ring symmetric Keller surfaces to higher dimensions, and proposed possible solutions to the proof of general stability conjecture. , Making it possible to completely solve the general stability conjecture.
Trainee reporter Du Peng