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Chinese scientists first observed triple degenerated fermions

External evaluation This discovery is of great significance - to break the conventional classification of the new fermion study, for the understanding of the nature of the basic particles is of great significance. Even more rare is that the study from the theoretical prediction, sample preparation to the experimental observation of the whole process, by our scientists independently completed.

Recently, many science and technology media have been reported in the important position of the Chinese Academy of Sciences Institute of Physics research team in the field of topology research made a major breakthrough: China's scientists first observed triple degenerated fermions, solid materials for the electronic topology research A new direction. The results of this study on June 19 online published in the "natural" on.

External evaluation This discovery is of great significance - to break the conventional classification of the new fermion study, for the understanding of the nature of the basic particles is of great significance. Even more rare is that the study from the theoretical prediction, sample preparation to the experimental observation of the whole process, by our scientists independently completed.

This is the result of attracting the eyes of the world from the Chinese Academy of Sciences a group of young scientists. Weng Hongming, Qian Tian, ​​Shi Youguo is the backbone of the team members, they come from different provinces and cities, learn different professional. At the same time, they have a common experience, such as in the late 90s into the university, in the early 21st century to study in Japan and quickly return home. In the scientific research line quietly more than ten years later, they may enter the "outbreak period."

Theory, sample, experiment, one can not be less

In the physics of the young people, the researcher Weng Hongming is a small celebrity one, in the know almost often "Fang Zhong, Dai Xi and Weng Hongming is not representative of the world's condensed state physics top level" like "gossip "problem. As a theoretical physicist, Weng Hongming specializes in the calculation and design of quantum materials. In 2015, he and Fang Chen, Dai Xi, Fang Zhong, together with the first theoretical prediction and experimental team, for the first time confirmed the outer semi-metal arsenide tantalum family material exists. In 2016, they further "prophesied" that there was a triple degenerate electronic state in a class of tungsten carbide crystal structures. The results of the "natural" release from an experimental point of view confirmed a year ago triple Jane Fermi's prediction is correct. And the completion of these two experimental observations is the physical by the Ding Hong, Qian days team.

Often, physics is divided into two broad categories, namely, theoretical physics and experimental physics. Theoretical physics through theoretical deduction and formula projections of the conclusion is called "prophecy", "prophecy" must be verified by the experiment to become an internationally recognized fact.

It may be noted that the physical summary of several major discoveries will be repeatedly mentioned, "theoretical prediction, the sample preparation to the experimental observation of the whole process", in the view of scientists, it is these three links ring Have to have their repeated success. "Which is not a link, this time can walk in the rest of the world before the first observation of triple Jane Fermi is the result of our cooperation." Weng Hongming said.

Weng Hongming and Qian Tian said that scientific research alone by a group or even rely on the power of a group is not enough, when there are important mission objectives, we have several groups seamless docking, whether it was discovered that year ago, semi-metal or this discovery Triple degenerated fermions are victorious in theory, the sample, the experiment is closely integrated.

Here we have to mention the preparation of samples, many research institutions may ignore this link. "But the physical does not exist this problem." Shiyou Guo said cheerfully. He is a physical researcher, sample preparation experts, born a smile face, but trained a hard effort. In the discovery of triple degenerated fermions in the process, he after several groping, and soon grow high-quality samples for the team to win a valuable time.

It is necessary to work hard, but also chatting

Shi Youguo said he was doing "physical labor". It is true that manual work is true, because the process of sample preparation and extraction can not be interrupted, and the quality and size of the sample requirements are particularly high, so Shiyou Guo and team members often in the laboratory for a few hours , Wearing several layers of gloves, hot sweat, wet clothes. "I usually love to engage in exercise, I was physically alive, the body can not do a good job." Shi Youguo said with a smile.

This physical activity, Shiyou Guo insisted on doing more than ten years, but colleagues say that the sample growth is a craft, need to accumulate and explore long-term labor. Domestic and foreign counterparts often find him to take samples, no sample can not do experiments.

So the money days be "near the water tower first month", a lot of samples of stone friends always ready for his first time out. "This time is the rapid preparation of the family of tungsten carbide family of molybdenum phosphide monocrystalline samples, after several months of repeated experimental measurements, the successful analysis of the electronic structure of molybdenum phosphide, observed in the triple degenerate point, and Weng Hongming Their results are highly consistent, the first experiment to confirm the breakout of the traditional classification of the triple Jane Fermi. "Qian days said.

Qian Tianchang with a baby face, looks a little rhetoric, but he himself said that the biggest favorite is the usual chat. "In the past, it was hard to see the literature, and the experiment was able to solve the problem. Later, it was equally important to find communication with people, because new ideas and new methods could be obtained from different people," he said.

The physics of the cafe in the circle of prestigious, legend here, the coffee is delicious and often have a "science big coffee" here "spark collision". And predecessors, Weng Hongming, Shi Youguo and Qian Tian also the cafe as their little world, Weng Hongming what new ideas must tell them the first time, Shi Youguo and Qian days in the course of the experiment what new discovery or Doubts will be the first time to feedback to Weng Hongming.

"Chat will be able to exchange information, our exchange is completely open, unreservedly let everyone know what we do." Weng Hongming said.

Ten years grinding sword, there have been wandering when confused

People's imagination, the life of theoretical physicists like "old monk into the set" - sat after pondering Emmanuel, but now they have changed the rhythm. "The first thing to work every day is to look at the latest scientific research in the world, to understand the world's most cutting-edge research and progress, and then analyze, think, calculate, and then communicate their ideas with colleagues." Weng Hongming said.

From 2000 in Nanjing University to study theoretical physics doctoral degree to the present, Weng Hongming in this area has accumulated more than 10 years, always in their own scientific research direction perseverance. But in physics, they are still small generation.

Speaking, this generation of young scientists bear a lot of pressure. Before they have many outstanding achievements of the predecessors, after they have a lot of halo plus returnees talent. They have doubts: "their own research in the end can not make great achievements?"

"But these years, I have been insisting, start the sample to more and more smoothly." Shiyou said. Money days have the same feeling. He said that the experimental process has many uncertainties, success, failure is common. There was a lot of twists and turns in the middle of the experimental study of the triple degenerate fermions. Fortunately, after a few months of experimentation, they finally succeeded. Once the experiment starts, it is 24 hours without stopping, day and night in the laboratory. Stay up late is common, money days and his colleagues is this "boil" over.

A few months ago, Qian Tian and Shiyou Guo had a chat, to explore the scientific research and scientific research is the issue of confidence. Talk to the end of their mutual encouragement that adhere to the work will always usher in the harvest day. A few months later, they published in the "Nature" triple Jane Fermi article, won the attention of the world.

Prices bullish may lead to domestic tungsten market confusion

Price bullish may lead to domestic tungsten market chaos According to the China Tungsten Association, the person in charge, last year China's tungsten exports are a record high value. Tungsten exports amounted to 802.468 million US dollars, an increase of 144.7% over the previous year. Significant increase in tungsten exports In addition to tungsten exports growth factors, mainly due to tungsten prices increase in export prices.

In the history of China's tungsten imports and exports for the first time the emergence of tungsten tungsten tungsten average price is greater than the average price of imported tungsten tungsten situation. This is mainly due to the growth of domestic processing demand, changes in import structure, tungsten ore and its concentrate and other low-cost imports of resource products increased, with the domestic enterprises is expected to continue to increase demand for raw materials, this year this The situation will continue. As the tungsten prices bullish, a large number of investors have to invest in tungsten ore, last year the domestic tungsten concentrate production capacity has more than 10,000 tons, the current Xinjiang, Gansu, Inner Mongolia, Jilin, Hunan, Yunnan and other places continue to build or build Tungsten mining enterprises, while foreign tungsten mines are also restored or expanded. Domestic tungsten smelting production capacity is still expanding, last year, tungsten and ammonium acid production capacity of 131,000 tons,

An increase of 15,000 tons, is still in the construction of secondary tungsten and ammonium acid production capacity there are 16,000 tons. Carbide, tungsten production capacity is also expanding. But the industry generally worried that a substantial increase in tungsten concentrate production will accelerate the consumption of tungsten resources in China, once again caused the domestic tungsten city chaos. It is expected that this year the domestic tungsten market will be some changes, when the expansion of domestic and foreign construction and new mines are put into production, the tungsten concentrate and the price of various tungsten goods will be reduced to the level before 2003.

China's Indian relations are unstable, and the export of super-hard industry is changing

July 10, the foreign media said that in the Donglang region after the confrontation between China and India led to the relationship after the cold, China in India or the upcoming Chinese citizens to pay attention to the safety of the reminder.

The Chinese Embassy in India issued a warning that the timing was intriguing

"It's not a travel warning," he said. "It's a reminder of the safety of Chinese tourists," an Indian Foreign Ministry official said.

The Chinese Embassy in India issued this reminder.

Over the past three weeks, China and India are close to Bhutan and India, China's three countries at the junction of the Donglang area confrontation.

According to Taiwan's "Central News Agency" reported on July 8, when the Sino-Indian border confrontation tension has not yet alleviated the occasion, the Chinese Embassy in India issued a statement to remind the Indian and the upcoming Indian citizens, pay close attention to the local security situation, Self-protection awareness.

The statement also said that in India and the upcoming mainland people should be informed in advance to the family, colleagues, friends travel situation, keep the communication smooth, carry personal identification, cautious, strict compliance with Indian laws and regulations, respect for local religious customs and customs , With local law enforcement officers to check.

Reported that the Chinese Embassy in India suddenly issued the warning statement, the timing of intriguing.

Super-hard industry exports to the Indian market for two consecutive years the US market

According to the China Superhard Materials Industry Association statistics customs data show: 2016, the statistics of the diamond, diamond grinding wheel, diamond circular saw blade, superhard materials, cutting tools and other four categories of goods exports total about 960 million US dollars. India's market continues to occupy the first destination of China's diamond, diamond circular saw blades, diamond cutting tools, the first three categories of export products, but also from the second year of 2015 than the US market, the market development potential.

Among them, the customs statistics 2016 diamond export destination of the top six, respectively, India, the United States, Japan, Korea, Hong Kong, China, Ireland, India scheduled first, the export volume of 580 million carats, accounting for 21.89% Compared with 2015 growth rate of 13.73%;

The first six export destinations for diamond wheels in 2016 were India, Vietnam, Brazil, Malaysia, the United States, Turkey and India, ranking 566.8 tons, accounting for 34.0% of the total export volume.

2016 diamond saw blade export destination of the top six, respectively, India, the United States, Germany, Brazil, Vietnam, Japan, India ranked first, exports amounted to 11846.3 tons, accounting for 18.7% of total exports;

2016 diamond / CBN tool export data show that exports totaled 5320.9 tons, India ranked third, accounting for 9.2% of total exports.

It is predicted that from 2016 to 2020, the international machine tool consumer market development tends to be stable, or showing a modest rebound in the new round of industrial chain restructuring and industrial transfer, driven by the future international market will be a new increase, Especially in India's infrastructure and automotive industry will be China's super-hard materials industry to bring a huge market.

2017 Sino-Indian relations: the largest Chinese trade survey was actually India

In 2016, China's imports and exports to the EU amounted to 3.61 trillion yuan, and the EU initiated 9 trade remedy investigations to China. In 2016, China imported and exported 3.43 trillion yuan to the United States, 20 in the United States launched a trade remedy investigation against China; India's import and export of 462.7 billion yuan, only China's import and export to the EU less than 1/7, but India launched a trade remedy investigation to China reached 21, as China launched a trade remedy survey of the largest countries.

This trend is still continuing, July 6, the Ministry of Commerce spokesman said the peak, the first half of this year, India's trade remedy investigations to China reached 12, once again to China to launch the largest trade survey countries.

China's super-hard materials network that: with India's infrastructure and automotive industry investment and development, China's superhard materials industry will bring a very broad market prospects, more China's super-hard materials industry to provide a backup and upgrading power. However, with the uncertainty of the future trend of Sino-Indian relations and the instability of China-India trade and other factors, China's super-hard materials industry enterprises should be prepared in advance to respond.

American Metal Powder Industry Association awarded the 2008 Powder Metallurgy Design Competition Award

The gears made by Cap stan Atlantic company can be used in a commercial printer to obtain a hardware / appliance award. This kind of tooth The gears are composed of large and small gears. The surface density of the gears after surface densification is 71 8 g / cm3, and the density of the two gears is 71 3 g / cm3. The manufacturing precision of the large gear is A GMA Q10. The manufacturing precision of the pinion is A GMA Q8. The fatigue strength of the gear tooth is the same as that of the 8620 forged steel after carbonization. The gear group is replaced by the powder metallurgy method. Machining gears can save more than 40% of the cost. Kinetics Climax Co., Ltd. has adopted a metal injection molding process to create a set of lock parts with hardware / equipment category honor award. These metal injection molding processes are made of 17 - 4P H stainless steel, which are made of locking rods, pins and racks. The density of these powder metallurgy parts is 71 7 g / cm3, and the typical resistance The tensile strength is 128 000 p si, and the typical yield strength is 100 000 p si. These powder metallurgy parts work in a device called a Kwikset Smart Key drum, which can be easily used by the user. The use of metal injection molding process to create these parts can be significantly cost savings, 100 (Black & Decker) has used these new products.

Mit subishi materials from Japan PM G Co., Ltd. can be used in a new type of car driving system in a set of high-strength gear group won the car chassis award. The gear set consists of a toothed lock and two cams made of powder metallurgy steel which is treated by diffusion alloying. The powder metallurgy parts have a density greater than 71 05 g / cm3 and a tensile strength greater than 159 000 p si. These powder metallurgy parts are made in a near-final form and the powder metallurgy process replaces the forging and machining processes commonly used to produce these parts Technology, Fuji Kiko Co., Ltd. Fuji Kiko Co., Ltd. has used these new products.

ASCO sintering company made a series of stainless steel bobbin won the car chassis honor award. These stainless steel bobbins can be used in new braking systems for racing cars and high-performance vehicles. These stainless steel bobbins can significantly extend the fatigue life of the brakes and also have the functions of cushioning thermal expansion, vibration and insulation. The powder metallurgy parts have a density of 71 0 g / cm3, a tensile strength of 70 000 p si, a yield strength of 45 000, an elongation of 13%, a Rockwell hardness of 65 HRB, an impact toughness of 48 ft · lb, Friction Products Co., Ltd. has used these new products.

Burgess2Norton manufacturing company can be applied to a six-speed automatic transmission in a slot plate and a tray to obtain the car transmission category award. The troughs and compartments are made of powder metallurgy sintered hardened steel with a plate weight of 01 84 kg (11 85 lb) and a heavy weight of 11 15 kg (21 54 lb), both of which are The density is 61 7 g / cm3, the trough of the trough is 75 000 p si, Tensile strength of 90 000 p si, compared to the use of forged steel parts, the use of powder metallurgy process can save about 70% of the cost, and can improve manufacturing accuracy. Ordinary industrial companies have used these new products, the annual output of these two parts is estimated to be more than 2.5 million, each year about 3.63 million kg (800 million lb) iron powder.