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Don't tell me you puts your D inside some chemicals.So for years I am 4D printing stuff at my home with this. Width, lenght, depth and " time "
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He who can create breast controls the World! 
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Congratulations to China
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Most complete nestling preserved in amber reveals details of ancient birds
(Xinhua) 13:06, June 08, 2017
BEIJING, June 8 -- An international team of scientists have identified the most complete hatchling specimen found so far encased in a Burmese amber, which provides a detailed look at young birds that lived nearly 99 million years ago.
According to Xing Lida from China University of Geosciences, who is leading the research, the 9-centimeter-long specimen included most of the skull and neck, a partial wing and hindlimb, and soft tissue of the tail.
Xing said the proportions of body parts and form of the feathers indicated it was a very young and highly advanced hatchling, adding that the unusually detailed feathers revealed unexpected diversity in primitive birds.
"Many people thought it was a lizard. But the scales, thread-like feathers and sharp claws on the feet were so noticeable that I thought they must belong to a bird," said Chen Guang, owner of the specimen and curator of a museum in Yunnan, the province that borders Myanmar.
"There were no obvious signs of struggle. The overall posture of the bird resembled hunting, with its lifted body, open claws and beak and spread wings," said Tseng Kuowei with the University of Taipei. "It was possibly engulfed by falling resin at the exact moment it was hunting."
The paper titled "A mid-Cretaceous enantiornithine (Aves) hatchling preserved in Burmese amber with unusual plumage," co-authored by a group of Chinese, Canadian and American scientists, was published by Gondwana Research this month.
(Photos from Beijing Youth Daily Weibo account)
(Xinhua) 13:06, June 08, 2017
BEIJING, June 8 -- An international team of scientists have identified the most complete hatchling specimen found so far encased in a Burmese amber, which provides a detailed look at young birds that lived nearly 99 million years ago.
According to Xing Lida from China University of Geosciences, who is leading the research, the 9-centimeter-long specimen included most of the skull and neck, a partial wing and hindlimb, and soft tissue of the tail.
Xing said the proportions of body parts and form of the feathers indicated it was a very young and highly advanced hatchling, adding that the unusually detailed feathers revealed unexpected diversity in primitive birds.
"Many people thought it was a lizard. But the scales, thread-like feathers and sharp claws on the feet were so noticeable that I thought they must belong to a bird," said Chen Guang, owner of the specimen and curator of a museum in Yunnan, the province that borders Myanmar.
"There were no obvious signs of struggle. The overall posture of the bird resembled hunting, with its lifted body, open claws and beak and spread wings," said Tseng Kuowei with the University of Taipei. "It was possibly engulfed by falling resin at the exact moment it was hunting."
The paper titled "A mid-Cretaceous enantiornithine (Aves) hatchling preserved in Burmese amber with unusual plumage," co-authored by a group of Chinese, Canadian and American scientists, was published by Gondwana Research this month.
(Photos from Beijing Youth Daily Weibo account)
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FOR IMMEDIATE RELEASE | May 24, 2017
Feather-light metal cathodes for stable lithium-oxygen batteries
"Nanoengineered ultralight and robust all-metal cathode for high-capacity, stable lithium–oxygen batteries"
ACS Central Science
Nanoporous nickel cathodes for lithium oxygen batteries are ultralight, shown here balanced on flower stamens.
Credit: American Chemical Society
Lithium-oxygen systems could someday outperform today’s lithium-ion batteries because of their potential for high energy density. However, a number of important issues, such as their poor electrochemical stability must be addressed before these systems can successfully compete with current rechargeable batteries. Today, in ACS Central Science, researchers report a new type of cathode, which could make lithium-oxygen batteries a practical option.
Xin-Bo Zhang and colleagues note that most of the problems associated with lithium-oxygen battery systems arise from two highly reduced oxygen species that react readily with the electrolyte and the cathode. Carbon is a common strong-performing cathode, but it is unstable in these systems. So, the team hypothesized that the key to unlocking lithium-oxygen batteries’ potential could be to create cathodes that are unreactive to the reduced oxygen species, but that still have the same highly conductive, low-weight, porous characteristics of carbon cathodes. The researchers succeeded in creating an ultralight all-metal cathode.
The design incorporated three forms of nickel including a nanoporous nickel interior and a gold-nickel alloy surface directly attached to nickel foam. Compared to carbon cathodes, the system has much higher capacity and is stable for 286 cycles, which is amongst the best for lithium-oxygen systems, and is nearly competitive with current commercial lithium-ion systems. Further experimentation showed that the stability and performance arise from both the metal used and its nanoporous structure, and that both these aspects could be optimized to further improve performance.
The authors acknowledge funding from the Chinese Academy of Sciences, Ministry of Science and Technology of the People's Republic of China, Technology and Industry for National Defense of the People's Republic of China, National Natural Science Foundation of China and Jilin Province Science and Technology Development Program.
Feather-light metal cathodes for stable lithium-oxygen batteries - American Chemical Society
Feather-light metal cathodes for stable lithium-oxygen batteries
"Nanoengineered ultralight and robust all-metal cathode for high-capacity, stable lithium–oxygen batteries"
ACS Central Science
Credit: American Chemical Society
Lithium-oxygen systems could someday outperform today’s lithium-ion batteries because of their potential for high energy density. However, a number of important issues, such as their poor electrochemical stability must be addressed before these systems can successfully compete with current rechargeable batteries. Today, in ACS Central Science, researchers report a new type of cathode, which could make lithium-oxygen batteries a practical option.
Xin-Bo Zhang and colleagues note that most of the problems associated with lithium-oxygen battery systems arise from two highly reduced oxygen species that react readily with the electrolyte and the cathode. Carbon is a common strong-performing cathode, but it is unstable in these systems. So, the team hypothesized that the key to unlocking lithium-oxygen batteries’ potential could be to create cathodes that are unreactive to the reduced oxygen species, but that still have the same highly conductive, low-weight, porous characteristics of carbon cathodes. The researchers succeeded in creating an ultralight all-metal cathode.
The design incorporated three forms of nickel including a nanoporous nickel interior and a gold-nickel alloy surface directly attached to nickel foam. Compared to carbon cathodes, the system has much higher capacity and is stable for 286 cycles, which is amongst the best for lithium-oxygen systems, and is nearly competitive with current commercial lithium-ion systems. Further experimentation showed that the stability and performance arise from both the metal used and its nanoporous structure, and that both these aspects could be optimized to further improve performance.
The authors acknowledge funding from the Chinese Academy of Sciences, Ministry of Science and Technology of the People's Republic of China, Technology and Industry for National Defense of the People's Republic of China, National Natural Science Foundation of China and Jilin Province Science and Technology Development Program.
Feather-light metal cathodes for stable lithium-oxygen batteries - American Chemical Society
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The New Type of Graphene Films: Super Flexible, Highly Conductive
By Babak Mostaghaci
Posted on May 19, 2017
In solid materials, heat is carried by acoustic phonons and electrons. The thermal conductivity (K) of metals is mainly attributed to high concentration of transport electrons. In this context, silver has the maximum thermal conductivity with a K value around 429 W m-1 K-1 at room temperature. To reach higher thermal conductivity, the only option is to use non-metallic materials, as their heat conduction is usually dominated by phonons, the particle-core vibrations in a crystal lattice, as in the cases of diamond and semi-metallic graphite. For the same material, K is mainly scaled with the size of crystal domain but limited by the concentration of defects, such as interfaces, boundaries, impurities, and holes. Therefore, a prominent thermal conductive material is usually pure, highly crystallized and defect-free, which in turn inevitably leads to brittleness because of the strong bonding and close-packed three-dimensional structure. Hence, prominent K and exceptional flexibility are hard to be integrated into one macroscopic material.
In a recent paper published in Advanced Materials, Prof. Chao Gao and colleagues in Zhejiang University report an ultra-high thermal conductive yet super-flexible graphene film. They fold the atomic thin crystals of neat large-sized graphene into micro-folds. Using a debris-free giant graphene oxide to reduce defective grain boundaries and extremely high-temperature annealing process to obtain defect-free graphene sheets results in a super high K of 1940 ± 113 W m−1 K−1, which is around five times more than copper’s thermal conductivity. On the other hand, they press semi-fullerene-like micro-gasbags into micro-folds to accommodate large elongation (16%) under external tension and provide enough deformation freedom, for more than 100,000 cycles of bending and 6,000 cycles of ultimate folding.
This design concept and experimental technique strategy can be extended to other two-dimensional nanomaterials such as BN, MoS2, graphdiyne, and black phosphorus, without fundamental obstacles. Various large-area multifunctional two-dimensional materials can be integrated into flexible devices in the real world, spanning from the aerospace industry to smartphones.
The New Type of Graphene Films: Super Flexible, Highly Conductive - Advanced Science News
Li Peng, Zhen Xu, Zheng Liu, Yan Guo, Peng Li, Chao Gao. Ultrahigh Thermal Conductive yet Superflexible Graphene Films. Advanced Materials (2017). DOI: 10.1002/adma.201700589
By Babak Mostaghaci
Posted on May 19, 2017
In solid materials, heat is carried by acoustic phonons and electrons. The thermal conductivity (K) of metals is mainly attributed to high concentration of transport electrons. In this context, silver has the maximum thermal conductivity with a K value around 429 W m-1 K-1 at room temperature. To reach higher thermal conductivity, the only option is to use non-metallic materials, as their heat conduction is usually dominated by phonons, the particle-core vibrations in a crystal lattice, as in the cases of diamond and semi-metallic graphite. For the same material, K is mainly scaled with the size of crystal domain but limited by the concentration of defects, such as interfaces, boundaries, impurities, and holes. Therefore, a prominent thermal conductive material is usually pure, highly crystallized and defect-free, which in turn inevitably leads to brittleness because of the strong bonding and close-packed three-dimensional structure. Hence, prominent K and exceptional flexibility are hard to be integrated into one macroscopic material.
In a recent paper published in Advanced Materials, Prof. Chao Gao and colleagues in Zhejiang University report an ultra-high thermal conductive yet super-flexible graphene film. They fold the atomic thin crystals of neat large-sized graphene into micro-folds. Using a debris-free giant graphene oxide to reduce defective grain boundaries and extremely high-temperature annealing process to obtain defect-free graphene sheets results in a super high K of 1940 ± 113 W m−1 K−1, which is around five times more than copper’s thermal conductivity. On the other hand, they press semi-fullerene-like micro-gasbags into micro-folds to accommodate large elongation (16%) under external tension and provide enough deformation freedom, for more than 100,000 cycles of bending and 6,000 cycles of ultimate folding.
This design concept and experimental technique strategy can be extended to other two-dimensional nanomaterials such as BN, MoS2, graphdiyne, and black phosphorus, without fundamental obstacles. Various large-area multifunctional two-dimensional materials can be integrated into flexible devices in the real world, spanning from the aerospace industry to smartphones.
The New Type of Graphene Films: Super Flexible, Highly Conductive - Advanced Science News
Li Peng, Zhen Xu, Zheng Liu, Yan Guo, Peng Li, Chao Gao. Ultrahigh Thermal Conductive yet Superflexible Graphene Films. Advanced Materials (2017). DOI: 10.1002/adma.201700589
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Technological breakthrough raises nuclear fuel utilization rate: below 1% to 95%
(People's Daily Online) 13:36, June 09, 2017
Chinese scientists have made a technological breakthrough in the country's nuclear energy program. The new accelerator-driven system (ADS) is able to raise the utilization rate of uranium to 95 percent, a great leap forward from less than 1 percent using the current technology, paving way for a safer, greener nuclear future, said the Chinese Academy of Sciences (CAS) at a press conference on June 8.
The new system means that fission energy could be sustainable for roughly 10, 000 years. It’s also more environmentally friendly, as it can shorten the radioactive life of used nuclear fuel to less than 500 years, and the volume of disposed nuclear waste can be reduced to less than 4 percent of the conventional amount.
Xu Hushan, vice director of the Institute of Modern Physics under CAS, said the achievement in advanced fission energy is the result of six years of research by the institute. The disappointingly low utilization rate of nuclear fuel and its safe disposal have been key challenges for the nuclear power industry.
25MeV连续波超导质子直线加速器
25MeV continuous wave superconducting proton linear accelerator
(People's Daily Online) 13:36, June 09, 2017
Chinese scientists have made a technological breakthrough in the country's nuclear energy program. The new accelerator-driven system (ADS) is able to raise the utilization rate of uranium to 95 percent, a great leap forward from less than 1 percent using the current technology, paving way for a safer, greener nuclear future, said the Chinese Academy of Sciences (CAS) at a press conference on June 8.
The new system means that fission energy could be sustainable for roughly 10, 000 years. It’s also more environmentally friendly, as it can shorten the radioactive life of used nuclear fuel to less than 500 years, and the volume of disposed nuclear waste can be reduced to less than 4 percent of the conventional amount.
Xu Hushan, vice director of the Institute of Modern Physics under CAS, said the achievement in advanced fission energy is the result of six years of research by the institute. The disappointingly low utilization rate of nuclear fuel and its safe disposal have been key challenges for the nuclear power industry.
25MeV连续波超导质子直线加速器
25MeV continuous wave superconducting proton linear accelerator
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JSCh
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Solving systems of linear equations with quantum mechanics
June 9, 2017 by Lisa Zyga
(Left) False color photomicrograph and (right) simplified circuit diagram of the superconducting quantum circuit for solving 2 × 2 linear equations. The method uses four qubits, marked Q1 to Q4, with four corresponding readout resonators, marked R1 to R4. Credit: Zheng et al. © 2017 American Physical Society
(Phys.org)—Physicists have experimentally demonstrated a purely quantum method for solving systems of linear equations that has the potential to work exponentially faster than the best classical methods. The results show that quantum computing may eventually have far-reaching practical applications, since solving linear systems is commonly done throughout science and engineering.
The physicists, led by Haohua Wang at Zhejiang University and Chao-Yang Lu and Xiaobo Zhu at the University of Science and Technology of China, along with their coauthors from various institutions in China, have published their paper on what they refer to as a "quantum linear solver" in a recent issue of Physical Review Letters.
"For the first time, we have demonstrated a quantum algorithm for solving systems of linear equations on a superconducting quantum circuit," Lu told Phys.org. "[This is] one of the best solid-state platforms with excellent scalability and remarkable high fidelity."
The quantum algorithm they implemented is called the Harrow, Hassidim, and Lloyd (HHL) algorithm, which was previously shown to have the ability, in principle, to lead to an exponential quantum speedup over classical algorithms. However, so far this has not been experimentally demonstrated.
In the new study, the scientists showed that a superconducting quantum circuit running the HHL algorithm can solve the simplest type of linear system, which has two equations with two variables. The method uses just four qubits: one ancilla qubit (a universal component of most quantum computing systems), and three qubits that correspond to the input vector b and the two solutions represented by the solution vector x in the standard linear system Ax = b, where A is a 2 x 2 matrix.
By performing a series of rotations, swappings of states, and binary conversions, the HHL algorithm determines the solutions to this system, which can then be read out by a quantum nondemolition measurement. The researchers demonstrated the method using 18 different input vectors and the same matrix, generating different solutions for different inputs. As the researchers explain, it is too soon to tell how much faster this quantum method might work since these problems are easily solved by classical methods.
"The whole calculation process takes about one second," Zhu said. "It is hard to directly compare the current version to the classical methods now. In this work, we showed how to solve the simplest 2 x 2 linear system, which can be solved by classical methods in a very short time. The key power of the HHL quantum algorithm is that, when solving an 's-sparse' system matrix of a very large size, it can gain an exponential speed-up compared to the best classical method. Therefore, it would be much more interesting to show such a comparison when the size of the linear equation is scaled to a very large system."
The researchers expect that, in the future, this quantum circuit could be scaled up to solve larger linear systems. They also plan to further improve the system's performance by making some straightforward adjustments to the device fabrication to reduce some of the error in its implementation. In addition, the researchers want to investigate how the circuit could be used to implement other quantum algorithms for a variety of large-scale applications.
"Our future research will focus on improving the hardware performance, including longer coherence times, higher precision logic gates, larger numbers of qubits, lower crosstalk, better readout fidelity, etc.," Wang said. "Based on the improvement of the hardware, we will demonstrate and optimize more quantum algorithms to really show the power of the superconducting quantum processor."
More information: Yarui Zheng et al. "Solving Systems of Linear Equations with a Superconducting Quantum Processor." Physical Review Letters. DOI: 10.1103/PhysRevLett.118.210504. Also at arXiv:1703.06613 [quant-ph]
https://phys.org/news/2017-06-linear-equations-quantum-mechanics.html
June 9, 2017 by Lisa Zyga
(Left) False color photomicrograph and (right) simplified circuit diagram of the superconducting quantum circuit for solving 2 × 2 linear equations. The method uses four qubits, marked Q1 to Q4, with four corresponding readout resonators, marked R1 to R4. Credit: Zheng et al. © 2017 American Physical Society
(Phys.org)—Physicists have experimentally demonstrated a purely quantum method for solving systems of linear equations that has the potential to work exponentially faster than the best classical methods. The results show that quantum computing may eventually have far-reaching practical applications, since solving linear systems is commonly done throughout science and engineering.
The physicists, led by Haohua Wang at Zhejiang University and Chao-Yang Lu and Xiaobo Zhu at the University of Science and Technology of China, along with their coauthors from various institutions in China, have published their paper on what they refer to as a "quantum linear solver" in a recent issue of Physical Review Letters.
"For the first time, we have demonstrated a quantum algorithm for solving systems of linear equations on a superconducting quantum circuit," Lu told Phys.org. "[This is] one of the best solid-state platforms with excellent scalability and remarkable high fidelity."
The quantum algorithm they implemented is called the Harrow, Hassidim, and Lloyd (HHL) algorithm, which was previously shown to have the ability, in principle, to lead to an exponential quantum speedup over classical algorithms. However, so far this has not been experimentally demonstrated.
In the new study, the scientists showed that a superconducting quantum circuit running the HHL algorithm can solve the simplest type of linear system, which has two equations with two variables. The method uses just four qubits: one ancilla qubit (a universal component of most quantum computing systems), and three qubits that correspond to the input vector b and the two solutions represented by the solution vector x in the standard linear system Ax = b, where A is a 2 x 2 matrix.
By performing a series of rotations, swappings of states, and binary conversions, the HHL algorithm determines the solutions to this system, which can then be read out by a quantum nondemolition measurement. The researchers demonstrated the method using 18 different input vectors and the same matrix, generating different solutions for different inputs. As the researchers explain, it is too soon to tell how much faster this quantum method might work since these problems are easily solved by classical methods.
"The whole calculation process takes about one second," Zhu said. "It is hard to directly compare the current version to the classical methods now. In this work, we showed how to solve the simplest 2 x 2 linear system, which can be solved by classical methods in a very short time. The key power of the HHL quantum algorithm is that, when solving an 's-sparse' system matrix of a very large size, it can gain an exponential speed-up compared to the best classical method. Therefore, it would be much more interesting to show such a comparison when the size of the linear equation is scaled to a very large system."
The researchers expect that, in the future, this quantum circuit could be scaled up to solve larger linear systems. They also plan to further improve the system's performance by making some straightforward adjustments to the device fabrication to reduce some of the error in its implementation. In addition, the researchers want to investigate how the circuit could be used to implement other quantum algorithms for a variety of large-scale applications.
"Our future research will focus on improving the hardware performance, including longer coherence times, higher precision logic gates, larger numbers of qubits, lower crosstalk, better readout fidelity, etc.," Wang said. "Based on the improvement of the hardware, we will demonstrate and optimize more quantum algorithms to really show the power of the superconducting quantum processor."
More information: Yarui Zheng et al. "Solving Systems of Linear Equations with a Superconducting Quantum Processor." Physical Review Letters. DOI: 10.1103/PhysRevLett.118.210504. Also at arXiv:1703.06613 [quant-ph]
https://phys.org/news/2017-06-linear-equations-quantum-mechanics.html
cirr
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Scientists create ultrastrong carbon material that's elastic like rubber
2017-06-11 06:47
Xinhua Editor: Gu Liping
Scientists have developed a form of ultrastrong, lightweight carbon that is hard as a diamond yet elastic like rubber and electrically conductive.
"In simple terms, the material combines the best properties of graphitic- and diamond-like forms of carbon," study co-lead author Zhisheng Zhao, professor at Yanshan University, China, said in an email to Xinhua.
"This combination of properties is useful for many potential applications, such as military armor and aerospace."
The findings were published this week by the U.S. journal Science Advances.
Carbon is an element of seemingly infinite possibilities. This is because it has the flexibility to form different types of chemical bonds, which allows it to exhibit a variety of fascinating structures.
According to Zhao, pressure is an effective tool to control this chemical bonding and induce so-called phase transformations.
For example, under high-pressure conditions, soft graphite transforms into diamond, the hardest material known.
In the new study, scientists pressurized and heated a structurally disordered form of carbon called glassy carbon to create the new form of carbon.
"The process is similar to converting graphite into diamond, however, in our new approach, the temperature used is not high enough to produce diamond," Zhao said.
"The resulting compressed glassy carbon exhibits exceptional hybrid properties in that it is lightweight, ultrastrong, very hard, elastic and electrically conductive."
Specifically, the compressed glassy carbon is more than two times stronger than commonly used carbon fibers, cemented diamond, silicon carbide and boron carbide ceramics.
It also has high hardness compared with commonly used ceramics, is electrically conducting and simultaneously exhibits a robust elastic recovery that's higher than shape-memory alloys and organic rubber.
"Our future work will continue to develop this methodology and create new structural materials with high strength, hardness and elasticity," said Zhao. "Our ultimate goal is to obtain the extremely strong and superhard materials with superelasticity."
The findings also included researchers from Carnegie Institution of Washington, and Shanghai-based Center for High Pressure Science and Technology Advanced Research, the University of Chicago and the Pennsylvania State University.
http://www.ecns.cn/2017/06-11/261001.shtml
2017-06-11 06:47
Xinhua Editor: Gu Liping
Scientists have developed a form of ultrastrong, lightweight carbon that is hard as a diamond yet elastic like rubber and electrically conductive.
"In simple terms, the material combines the best properties of graphitic- and diamond-like forms of carbon," study co-lead author Zhisheng Zhao, professor at Yanshan University, China, said in an email to Xinhua.
"This combination of properties is useful for many potential applications, such as military armor and aerospace."
The findings were published this week by the U.S. journal Science Advances.
Carbon is an element of seemingly infinite possibilities. This is because it has the flexibility to form different types of chemical bonds, which allows it to exhibit a variety of fascinating structures.
According to Zhao, pressure is an effective tool to control this chemical bonding and induce so-called phase transformations.
For example, under high-pressure conditions, soft graphite transforms into diamond, the hardest material known.
In the new study, scientists pressurized and heated a structurally disordered form of carbon called glassy carbon to create the new form of carbon.
"The process is similar to converting graphite into diamond, however, in our new approach, the temperature used is not high enough to produce diamond," Zhao said.
"The resulting compressed glassy carbon exhibits exceptional hybrid properties in that it is lightweight, ultrastrong, very hard, elastic and electrically conductive."
Specifically, the compressed glassy carbon is more than two times stronger than commonly used carbon fibers, cemented diamond, silicon carbide and boron carbide ceramics.
It also has high hardness compared with commonly used ceramics, is electrically conducting and simultaneously exhibits a robust elastic recovery that's higher than shape-memory alloys and organic rubber.
"Our future work will continue to develop this methodology and create new structural materials with high strength, hardness and elasticity," said Zhao. "Our ultimate goal is to obtain the extremely strong and superhard materials with superelasticity."
The findings also included researchers from Carnegie Institution of Washington, and Shanghai-based Center for High Pressure Science and Technology Advanced Research, the University of Chicago and the Pennsylvania State University.
http://www.ecns.cn/2017/06-11/261001.shtml
JSCh
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Array could help solve cosmic puzzle
By ZHANG ZHIHAO | China Daily | Updated: 2017-06-12 06:56
Editor's note: In the run-up to the 19th Communist Party of China National Congress, China Daily will cover a series of key projects and advanced equipment of national importance, showcasing the country's huge improvement and relentless efforts at innovation.
Observatory being built in Sichuan to discover what makes gamma rays tick
Imagine an explosion that can release 10 times the energy the sun radiates in its 10-billion-year life. It's called a hypernova, one of the brightest and most powerful stellar events.
Scientists suspect such an explosion would produce a large amount of cosmic rays, highly energetic particles blazing across the universe at close to the speed of light. These cosmic bullets pack so much energy they can cause electronics problems in satellites, planes and other devices on Earth after traveling for billions of years.
First discovered in 1912, cosmic rays continue to baffle scientists as to exactly where and how they are made. But China is spending more than 1.2 billion yuan ($176.53 million) to build the world's largest cosmic ray observatory for gamma ray astronomy to crack this mystery, and possibly to learn how to recreate the high-energy particles on Earth.
The installation is called Large High Altitude Air Shower Observatory－a 136-hectare telescope array spreading across Haizi Mountain in Daocheng county, Sichuan province. It consists of more than 6,300 detectors and 12 telescopes, and is located 4.4 kilometers above sea level, making it one of the highest cosmic ray observatories in the world.
Construction of the roads and basic groundwork around the observatory started last year, and work on the detectors is set to begin this year, said Li Kunpeng, the senior engineer for the project from the Chinese Academy of Sciences' Institute of High Energy Physics. By the end of next year, 25 percent of the observatory will be operational and able to receive data. The entire project is scheduled to be finished by about January 2021.
The observatory will be the world's most sensitive detector of ultrahigh-energy cosmic gamma rays carrying more than 10 trillion electron volts－a unit of energy－and is able to detect charged cosmic rays up to 10 quintillion (1 followed by 18 zeros) electron volts. This scale dwarfs the energy level from the sun's cosmic rays, which is typically measured in millions and up to billions, said Cao Zhen, the project's chief scientist.
"Ultrahigh-energy particles could be the remnants and messengers of major cosmic events that could have happened billions of years ago in distant galaxies," he said, adding that they are a million times stronger than the most energetic particle created by the world's most powerful particle accelerator, the Large Hadron Collider in Switzerland.
"By studying their origin and how they accelerate, we will have a better understanding of the early days of the universe, and, if possible, we can emulate their acceleration mechanism for research, leading to new discoveries beyond the limits of our current equipment," he said.
Such discoveries include new properties or laws in high-energy radiation, star formation, dark matter as well as other fundamental fields, Cao said. This can lead to new applications such as the new-generation gamma knife, in which highly energetic photon particles are used to kill brain tumors, or better materials to protect astronauts and electronics from cosmic rays.
Catching these space travelers is no simple task. Even if they reach the Earth, the atmosphere absorbs most of them. So the ideal method is to use satellites equipped with telescopes and detectors to intercept them in space, like NASA's Fermi Gamma-ray Space Telescope and China's Dark Matter Particle Explorer.
However, the more energy a particle has, the rarer it becomes. Some ultrahigh-energy particles occur only once a year within a 1-square-kilometer surface, Cao said.
As a result, it is more common and cost-efficient to lay out the massive detectors array－what scientists call a sky net－on mountains or below ground to reduce interference from air.
Similar installations are the Pierre Auger Observatory in Argentina, the IceCube Neutrino Observatory in Antarctica, which is under ice, the ARGO-YBJ International Observatory in the Tibetan Plateau, and later the planned Cherenkov Telescope Array.
"The LHAASO will complement these existing observatories, and will become an advanced platform for scientists around the world from astronomy to nanotechnology to work together in unraveling the mystery of the universe," said He Huihai, the project's chief technologist.
Scientists from France, Italy, Russia, Switzerland, Thailand and other countries will also collaborate in the project along with Chinese scientists from more than 20 institutions and universities, he added.
What makes the Large High Altitude Air Shower Observatory unique is its way of catching the cosmic rays. When a high-energy particle enters the atmosphere, it ionizes－sheds one or more electrons－and charges the molecules in the air, and the ionized molecules continue to bump into other molecules, he said.
After a dozen rounds, this creates a shower of secondary molecules spreading across a large area, "the LHAASO will catch parts of the shower within nanoseconds, analyze their data, and find the one particle that started it all", he added.
Once a particle is located, scientists can estimate the direction it came from and order telescopes to look in that area to see what happened.
Coupled with lightwave analysis and different types of telescopes, scientists can even deduce the chemical makeup of the situation and possibly figure out how the particles got so fast.
"Given its extreme difficulty, such a task is only possible through global effort," He said. "This is the best part of studying the cosmos, it unites scientists across nations and fields together under one purpose－to learn about the universe."
By ZHANG ZHIHAO | China Daily | Updated: 2017-06-12 06:56
Editor's note: In the run-up to the 19th Communist Party of China National Congress, China Daily will cover a series of key projects and advanced equipment of national importance, showcasing the country's huge improvement and relentless efforts at innovation.
Observatory being built in Sichuan to discover what makes gamma rays tick
Imagine an explosion that can release 10 times the energy the sun radiates in its 10-billion-year life. It's called a hypernova, one of the brightest and most powerful stellar events.
Scientists suspect such an explosion would produce a large amount of cosmic rays, highly energetic particles blazing across the universe at close to the speed of light. These cosmic bullets pack so much energy they can cause electronics problems in satellites, planes and other devices on Earth after traveling for billions of years.
First discovered in 1912, cosmic rays continue to baffle scientists as to exactly where and how they are made. But China is spending more than 1.2 billion yuan ($176.53 million) to build the world's largest cosmic ray observatory for gamma ray astronomy to crack this mystery, and possibly to learn how to recreate the high-energy particles on Earth.
The installation is called Large High Altitude Air Shower Observatory－a 136-hectare telescope array spreading across Haizi Mountain in Daocheng county, Sichuan province. It consists of more than 6,300 detectors and 12 telescopes, and is located 4.4 kilometers above sea level, making it one of the highest cosmic ray observatories in the world.
Construction of the roads and basic groundwork around the observatory started last year, and work on the detectors is set to begin this year, said Li Kunpeng, the senior engineer for the project from the Chinese Academy of Sciences' Institute of High Energy Physics. By the end of next year, 25 percent of the observatory will be operational and able to receive data. The entire project is scheduled to be finished by about January 2021.
The observatory will be the world's most sensitive detector of ultrahigh-energy cosmic gamma rays carrying more than 10 trillion electron volts－a unit of energy－and is able to detect charged cosmic rays up to 10 quintillion (1 followed by 18 zeros) electron volts. This scale dwarfs the energy level from the sun's cosmic rays, which is typically measured in millions and up to billions, said Cao Zhen, the project's chief scientist.
"Ultrahigh-energy particles could be the remnants and messengers of major cosmic events that could have happened billions of years ago in distant galaxies," he said, adding that they are a million times stronger than the most energetic particle created by the world's most powerful particle accelerator, the Large Hadron Collider in Switzerland.
"By studying their origin and how they accelerate, we will have a better understanding of the early days of the universe, and, if possible, we can emulate their acceleration mechanism for research, leading to new discoveries beyond the limits of our current equipment," he said.
Such discoveries include new properties or laws in high-energy radiation, star formation, dark matter as well as other fundamental fields, Cao said. This can lead to new applications such as the new-generation gamma knife, in which highly energetic photon particles are used to kill brain tumors, or better materials to protect astronauts and electronics from cosmic rays.
Catching these space travelers is no simple task. Even if they reach the Earth, the atmosphere absorbs most of them. So the ideal method is to use satellites equipped with telescopes and detectors to intercept them in space, like NASA's Fermi Gamma-ray Space Telescope and China's Dark Matter Particle Explorer.
However, the more energy a particle has, the rarer it becomes. Some ultrahigh-energy particles occur only once a year within a 1-square-kilometer surface, Cao said.
As a result, it is more common and cost-efficient to lay out the massive detectors array－what scientists call a sky net－on mountains or below ground to reduce interference from air.
Similar installations are the Pierre Auger Observatory in Argentina, the IceCube Neutrino Observatory in Antarctica, which is under ice, the ARGO-YBJ International Observatory in the Tibetan Plateau, and later the planned Cherenkov Telescope Array.
"The LHAASO will complement these existing observatories, and will become an advanced platform for scientists around the world from astronomy to nanotechnology to work together in unraveling the mystery of the universe," said He Huihai, the project's chief technologist.
Scientists from France, Italy, Russia, Switzerland, Thailand and other countries will also collaborate in the project along with Chinese scientists from more than 20 institutions and universities, he added.
What makes the Large High Altitude Air Shower Observatory unique is its way of catching the cosmic rays. When a high-energy particle enters the atmosphere, it ionizes－sheds one or more electrons－and charges the molecules in the air, and the ionized molecules continue to bump into other molecules, he said.
After a dozen rounds, this creates a shower of secondary molecules spreading across a large area, "the LHAASO will catch parts of the shower within nanoseconds, analyze their data, and find the one particle that started it all", he added.
Once a particle is located, scientists can estimate the direction it came from and order telescopes to look in that area to see what happened.
Coupled with lightwave analysis and different types of telescopes, scientists can even deduce the chemical makeup of the situation and possibly figure out how the particles got so fast.
"Given its extreme difficulty, such a task is only possible through global effort," He said. "This is the best part of studying the cosmos, it unites scientists across nations and fields together under one purpose－to learn about the universe."
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Physicists use quantum memory to demonstrate quantum secure direct communication
June 12, 2017 by Lisa Zyga
Experimental set-up of quantum secure direct communication with quantum memory. Credit: Zhang et al. ©2017 American Physical Society
For the first time, physicists have experimentally demonstrated a quantum secure direct communication (QSDC) protocol combined with quantum memory, which is essential for storing and controlling the transfer of information. Until now, QSDC protocols have used fiber delay lines as a substitute for quantum memory, but the use of quantum memory is necessary for future applications, such as long-distance communication over secure quantum networks.
The researchers, Wei Zhang et al., from the University of Science and Technology of China and Nanjing University of Posts and Telecommunications, have published a paper on their experimental demonstration in a recent issue of Physical Review Letters.
QSDC is one of several different types of quantum communication methods, and has the ability to directly transmit secret messages over a quantum channel. Unlike most other quantum communication methods, QSDC does not require that the two parties communicating share a private key in advance. Similar to other kinds of quantum communication, the security of the method relies on some of the basic principles of quantum mechanics, such as the uncertainty principle and the no-cloning theorem.
As the physicists explain, a quantum memory is necessary for QSDC protocols in order to effectively control the transfer of information in future quantum networks. However, experimentally realizing quantum memory with QSDC is challenging because it requires storing entangled single photons and establishing the entanglement between separated memories.
In their experiments, the researchers demonstrated most of the essential steps of the protocol, including entanglement generation; channel security; and the distribution, storage, and encoding of entangled photons. Due to the difficulty of decoding entangled photons in the optimal way (which requires distinguishing between four quantum states), the researchers used an alternative decoding method that is easier to implement.
In the future, the researchers expect that it will be possible to demonstrate QSDC across distances of 100 km or more in free space, similar to the recent demonstrations of quantum key distribution, quantum teleportation and entanglement distribution over these distances. Achieving this goal will mark an important step in realizing satellite-based long-distance and global-scale QSDC in the future.
More information: Wei Zhang et al. "Quantum Secure Direct Communication with Quantum Memory." Physical Review Letters. DOI: 10.1103/PhysRevLett.118.220501
https://phys.org/news/2017-06-physicists-quantum-memory.html
June 12, 2017 by Lisa Zyga
For the first time, physicists have experimentally demonstrated a quantum secure direct communication (QSDC) protocol combined with quantum memory, which is essential for storing and controlling the transfer of information. Until now, QSDC protocols have used fiber delay lines as a substitute for quantum memory, but the use of quantum memory is necessary for future applications, such as long-distance communication over secure quantum networks.
The researchers, Wei Zhang et al., from the University of Science and Technology of China and Nanjing University of Posts and Telecommunications, have published a paper on their experimental demonstration in a recent issue of Physical Review Letters.
QSDC is one of several different types of quantum communication methods, and has the ability to directly transmit secret messages over a quantum channel. Unlike most other quantum communication methods, QSDC does not require that the two parties communicating share a private key in advance. Similar to other kinds of quantum communication, the security of the method relies on some of the basic principles of quantum mechanics, such as the uncertainty principle and the no-cloning theorem.
As the physicists explain, a quantum memory is necessary for QSDC protocols in order to effectively control the transfer of information in future quantum networks. However, experimentally realizing quantum memory with QSDC is challenging because it requires storing entangled single photons and establishing the entanglement between separated memories.
In their experiments, the researchers demonstrated most of the essential steps of the protocol, including entanglement generation; channel security; and the distribution, storage, and encoding of entangled photons. Due to the difficulty of decoding entangled photons in the optimal way (which requires distinguishing between four quantum states), the researchers used an alternative decoding method that is easier to implement.
In the future, the researchers expect that it will be possible to demonstrate QSDC across distances of 100 km or more in free space, similar to the recent demonstrations of quantum key distribution, quantum teleportation and entanglement distribution over these distances. Achieving this goal will mark an important step in realizing satellite-based long-distance and global-scale QSDC in the future.
More information: Wei Zhang et al. "Quantum Secure Direct Communication with Quantum Memory." Physical Review Letters. DOI: 10.1103/PhysRevLett.118.220501
https://phys.org/news/2017-06-physicists-quantum-memory.html
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New Approach to Convert CO2 Directly into Gasoline
Jun 14, 2017
The research team has found a new approach to convert carbon dioxide directly into gasoline by using a bifunctional catalyst contained a reducible oxide (In2O3) and a zeolite (HZSM-5), which will not only help to alleviate the global warming caused by increasing atmospheric CO2 concentration, but also offer a solution to replace dwindling fossil fuels.
The paper by a joint research team from CAS Key Laboratory of Low-Carbon Conversion Science and Engineering of Shanghai Advanced Research Institute (SARI) and SARI-ShanghaiTech University Joint Lab was published in the leading scientific journal Nature Chemistry.
"Because carbon dioxide is extremely inert, previous recycling was mainly on converting it to chemicals like methanol. But our findings are able to convert the greenhouse gas into value-added chemicals with two or more carbons like gasoline directly. And the conversion is of very high efficiency due to the newly developed catalyst." said ZHONG Liangshu, one of the project researchers.
Currently, CO2-based Fischer–Tropsch synthesis (FTS) route over modified Fe-based catalysts can be used for the production of hydrocarbons. According to Anderson–Schulz–Flory distribution, however, the chain growth probability of FTS limits the proportion of desired C5–C11 hydrocarbons only with 48% at maximum of C5–C11 selectivity.
In addition, the degree of hydrogenation of surface-adsorbed intermediates in CO2-based FTS is higher due to the slower adsorption rate of CO2 when compared to CO hydrogenation, leading to more readily formation of methane with a decrease in chain growth.
In the present work, the bifunctional catalyst exhibits excellent performance for the direct production of long-chain hydrocarbons from CO2 hydrogenation with high selectivity.
The C5+ selectivity in hydrocarbons distribution (carbon atom-based) reached up to 78.6% with only 1% CH4 at a CO2 conversion of 13.1%. There was no obvious catalyst deactivation over 150 h, and much better performance was observed with internal gas recycling. Such results suggest a promising potential for its industrial application.
Direct conversion of CO2 into liquid fuels with high selectivity over a bifunctional catalyst (Image by SARI)
China is the world's biggest carbon emitter and much attention has been paid to cut emissions. Chinese President Xi Jinping made the pledge that China would peak CO2 emissions by around 2030 in his speech at the United Nations Conference on Climate Change in Paris. If CO2 can be directly and efficiently converted into liquid fuels, the dream toward cycling carbon by mimicking nature will come true.
Thanks to the support from the National Natural Science Foundation of China (NSFC), the Ministry of Science and Technology (MOST), the Shanghai Science and Technology Committee (STCSM) and Chinese Academy of Sciences (CAS), the research team has published the results on direct production of lower olefins from syngas in Nature last year.
The results are highlights for the integration of research and education between SARI and ShanghaiTech and have laid a solid foundation for the development of Zhangjiang Comprehensive National Science and Technology Center.
New Approach to Convert CO2 Directly into Gasoline---Chinese Academy of Sciences
Jun 14, 2017
The research team has found a new approach to convert carbon dioxide directly into gasoline by using a bifunctional catalyst contained a reducible oxide (In2O3) and a zeolite (HZSM-5), which will not only help to alleviate the global warming caused by increasing atmospheric CO2 concentration, but also offer a solution to replace dwindling fossil fuels.
The paper by a joint research team from CAS Key Laboratory of Low-Carbon Conversion Science and Engineering of Shanghai Advanced Research Institute (SARI) and SARI-ShanghaiTech University Joint Lab was published in the leading scientific journal Nature Chemistry.
"Because carbon dioxide is extremely inert, previous recycling was mainly on converting it to chemicals like methanol. But our findings are able to convert the greenhouse gas into value-added chemicals with two or more carbons like gasoline directly. And the conversion is of very high efficiency due to the newly developed catalyst." said ZHONG Liangshu, one of the project researchers.
Currently, CO2-based Fischer–Tropsch synthesis (FTS) route over modified Fe-based catalysts can be used for the production of hydrocarbons. According to Anderson–Schulz–Flory distribution, however, the chain growth probability of FTS limits the proportion of desired C5–C11 hydrocarbons only with 48% at maximum of C5–C11 selectivity.
In addition, the degree of hydrogenation of surface-adsorbed intermediates in CO2-based FTS is higher due to the slower adsorption rate of CO2 when compared to CO hydrogenation, leading to more readily formation of methane with a decrease in chain growth.
In the present work, the bifunctional catalyst exhibits excellent performance for the direct production of long-chain hydrocarbons from CO2 hydrogenation with high selectivity.
The C5+ selectivity in hydrocarbons distribution (carbon atom-based) reached up to 78.6% with only 1% CH4 at a CO2 conversion of 13.1%. There was no obvious catalyst deactivation over 150 h, and much better performance was observed with internal gas recycling. Such results suggest a promising potential for its industrial application.
China is the world's biggest carbon emitter and much attention has been paid to cut emissions. Chinese President Xi Jinping made the pledge that China would peak CO2 emissions by around 2030 in his speech at the United Nations Conference on Climate Change in Paris. If CO2 can be directly and efficiently converted into liquid fuels, the dream toward cycling carbon by mimicking nature will come true.
Thanks to the support from the National Natural Science Foundation of China (NSFC), the Ministry of Science and Technology (MOST), the Shanghai Science and Technology Committee (STCSM) and Chinese Academy of Sciences (CAS), the research team has published the results on direct production of lower olefins from syngas in Nature last year.
The results are highlights for the integration of research and education between SARI and ShanghaiTech and have laid a solid foundation for the development of Zhangjiang Comprehensive National Science and Technology Center.
New Approach to Convert CO2 Directly into Gasoline---Chinese Academy of Sciences
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