News on China's scientific and technological development.

China expects to launch fifth lunar probe Chang'e-5 in 2017

English.news.cn 2011-03-02 19:30:33 FeedbackPrintRSS

BEIJING, March 2 (Xinhua) -- China is expected to launch its fifth lunar probe, Chang'e-5, in 2017 to send back a moon rock sample to earth, a top Chinese space scientist told Xinhua Wednesday.

A lunar landing probe, lunar surface patrol device and other equipment would be carried by Chang'e-5, said Ye Peijian, chief designer of Chang'e-1, the country's first moon probe, and chief commander of the Chang'e-2 and Chang'e-3 missions.

"Chang'e-5 will also carry a drilling machine to get moon rock from a depth of 2 meters underground," he said.

He revealed that experts from Hong Kong and Macao would participate in the lunar probe project.

Ye was speaking ahead of his attendance at the annual session of the Chinese People's Political Consultative Conference (CPPCC) National Committee, China's top political advisory body, which is to convene Thursday.

China launched its first lunar probe, Chang'e-1, named after the country's mythical Moon Goddess, on Oct. 24, 2007, from the southwestern Sichuan Province. The probe ended its 16-month mission on March 1, 2009, when it crashed into the moon's surface.

The second lunar probe, Chang'e-2, was launched on Oct. 1 last year. It entered its long-term lunar orbit on Nov. 3, beginning a six-month mission to take high-resolution images of the moon's Sinus Iridum, or Bay of Rainbows.

Space authorities have revealed that China would launch its third unmanned probe to the moon, Chang'e-3, in 2013.

"A soft-landing on moon will be a main aim for Chang'e-3," Ye said.

A China-designed moon rover would land with Chang'e-3, he said.

The moon rover is a robot that can move and accomplish complicated tasks of detecting, collecting and analyzing samples.

After Chang'e-3, China would launch Chang'e-4 with the goal of achieving automatic patrols on the moon, Ye said.

But a launch time for the fourth lunar probe remains unknown.

According to China's three-phase moon exploration plan, the first phase was the launch of Chang'e-2. The second will be when Chang'e-3 lands on the moon in 2013. Then, in 2017, a moon rock sample will be returned to earth.

Space experts have said the country would conduct more than 20 space missions this year as it accelerated efforts to improve space technologies.

Last year China conducted 15 space missions.

Editor: Zhang Xiang

Godson: China shuns US silicon with faux x86 superchip



"Godson: China shuns US silicon with faux x86 superchip
Who needs GPU co-processors?
By Timothy Prickett Morgan
Posted in HPC, 25th February 2011 21:07 GMT

ISSCC If the Chinese government is scaring the world with its hybrid CPU-GPU clusters, what do you think the reaction will be when Chinese supercomputers shun American-made x64 processors and GPU co-processors and start using their own energy-efficient, MIPS-derived, x86-emulating Godson line of 64-bit processors?

Apoplexy? Disbelief? A polite bow of respect? A bunch of orders for Godson chips is more likely, once you see what China is up to.

One of the more interesting presentations at this week's International Solid-State Circuits Conference, hosted by the IEEE in San Francisco, was by Weiwu Hu, the lead designer of the Godson family of processors being created by Institute of Computing Technology at the Chinese Academy of Sciences.

China started developing its own processor since 2002, explained Hu, and the Godson family of chips, which is based on the MIPS architecture created by Silicon Graphics, is part of a holistic technology investment program. The Godson chip effort is one of 16 different projects, in fact, that are each funded with between $5bn and $10bn.

The massive projects focus on specific technology areas that China reckons are key for its technological independence and economic future, including processors and operating systems, chip process technology, 4G wireless networks, nuclear fission power plants, water pollution control and treatment, aircraft design and construction, high-resolution satellite imaging, and manned spaceflight and lunar exploration.

As El Reg reported a year ago when China's ICT was bragging about its plans to build a petaflops-scale supercomputer with server maker Dawning, ICT originally got access to MIPS technology through its partnership with wafer-baker STMicroelectronics. But in June 2009, as it got serious about its Godson chips (also known by the name Loongson) it licensed the MIPS32 and MIPS64 architectures straight from MIPS Technologies, the chip-designing division of Silicon Graphics that was spun out in an initial public offering in 1998.

The initial Godson-1 processors were 32-bit chips running at a mere 266 MHz, and the Godson-2 moved to 64-bits and was revved up to 1.2 GHz. With the Godson-2F chip in 2007 and 2008, ICT came out with a design that has a four-issue core running at 800 MHz, rated at 3.2 gigaflops. The Godson-3A chip was delayed nearly a year and was aimed solely at servers. ICT shifted a four-core design and also did something else very clever: it added x64 instruction emulation right into the hardware. Hu only alluded to this emulation capability, but as El Reg explained a year ago, the Godson-3 chips have instructions added to help the QEMU hypervisor (the one that's at the heart of Red Hat's KVM hypervisor) to translate instructions from x86 to MIPS format. According to early benchmarks, the emulation penalty is about 30 per cent.


ICT's Godson family of chips for servers, PCs, and consumer electronics

The Godson-3A chip was implemented in a 65 nanometer process and ran at 1 GHz to deliver 16 gigaflops of floating point oomph. The chip has 425 million transistors, an area of 174.5 square millimeters, and burned only 10 watts under load. The chip included two 16-bit HyperTransport ports (licensed from Advanced Micro Devices), 4 MB of L2 cache, and two on-chip memory controllers that support either DDR2 or DDR3 main memory.

Oh Godson!

With the Godson-3B, which is what Hu was there to talk about in San Francisco, ICT is sticking with the same 65 nanometer CMOS process and running the chip at the same 1 GHz. But the chip is bumped up to eight cores from four and has two 256-bit vector co-processors per core. The chip has two HyperTransport ports and two DDR3 memory controllers, and weighs in at 583 million transistors in a 300 square millimeter area. Running at 1 GHz, peak performance on those vector units is 128 gigaflops, with the chip only emitting 40 watts. According to early tests, the cores burn about 28.9 watts, while the uncore parts of the chip (HT, memory controllers, and crossbar switches for linking chips together) consume 11.1 watts.

According to Hu, the vector extension unit in the Godson-3B and Godson-2H processors have 128-entry, 256-bit register files and have more than 300 SIMD instructions that have been added to the MIPS architecture.

Here's what the Godson-3B chip looks like:


ICT's Godson-3B MIPS processor, x86 emulation included

The Godson-3B processor will be used in the Dawning 6000 petaflops supercomputer, which China will be tweaking in 2012. Here's an early version of the blade equipped for the Godson-3B chips:


Dawning's two-socket Godson-3A and Godson-3B blade server

And this is what the blade server chassis looks like for the Dawning 6000:


The Dawning 6000 supercomputer blade server chassis

The Dawning 6000 blade design is used by the National Supercomputing Center in Shenzhen for its hybrid Xeon 5650-Nvidia M2050 system, which ranked number three on the Top 500 list from November 2010. That machine had an aggregate 1.27 petaflops of sustained performance running the Linpack Fortran benchmark test.

Another Dawning 6000 blade cluster with 3,000 of the Godson-3B chips, and rated at around 300 sustained teraflops, is expected to be up and running this summer, Hu said. (That would be about 384 peak theoretical teraflops just counting the vector units, not the cores.)

Those Dawning 6000 blades are by no means the highest density that ICT can come up with. Check out this system board for a 1U rack server that Hu showed off at ISSCC this week:


ICT's 1U2T Godson-3B system board

This IU2T system board packs 16 of the eight-core Godson-3B processors onto a single board, rated at 2 teraflops. So a rack of these puppies would yield 42 teraflops. So instead of hundreds of cabinets to reach 1 petaflops of raw number-crunching performance, as it can take with big x64-based machines, ICT could, in theory, do it with 24 racks.

ICT is not going to stop here. The Godson-3C design will shift to a 28 nanometer process and will come in eight-core variants like the Godson-3B as well as a 16-core variant. The Godson-3C will have faster clock speeds, too, running at between 1.5 GHz and 2 GHz. The roadmap says the chip is also capable of expanding up to 16 cores, too. ICT says the Godson-3C will deliver 512 gigaflops of raw performance on math work, and the way the math works, that is twice as much math moving from 1 GHz to 2 GHz and then a doubling again as the core count goes from 8 to 16. This chip is expected sometime around late 2012 or early 2013.

Wouldn't it be funny if Silicon Graphics started building systems with these Godson-3 chips? They could dust off Irix and take it out for a spin on some new iron and allow it to run x64-based Linux applications in emulation mode."

World's largest rocket production base takes shape in northern China


A Chinese rocket awaiting launch.



"World's largest rocket production base takes shape in northern China
2011-03-03 17:23:22

BEIJING, March 3 (Xinhua) -- The world's largest design, production and testing base for rockets is being built in northern China's Tianjin Municipality, Liang Xiaohong, deputy head of the China Academy of Launch Vehicle Technology, told Xinhua Thursday.

The first phase of the rocket industrial base in Tianjin's Binhai New Area will be completed within the year. Rocket parts will be designed, manufactured, assembled and tested at the base, Liang said.

Twenty of the 22 plants have been completed, and some of them are ready for operation. The base is designed to meet China's growing demand in space technology research and development for the next 30 to 50 years, he added.

By integrating the industrial chain, the base will be able to produce a whole spectrum of rockets of different sizes and types for China's moon probe project, space station and other projects, he said.

China's new rockets, including Long March IV, will be designed and manufactured in the 200-hectare base, he said."

How To Turn A Laser Into A Tractor Beam



"How To Turn A Laser Into A Tractor Beam
Technology Review
Published by MIT
kfc 02/28/2011

Physicists work out how to generate a backward pulling force from a forward propagating beam.



A photon has a small momentum which it can impart to anything it hits, as Arthur Compton and Peter Lebedev discovered at the beginning of the last century. We now know that photons can be used to push anything from electrons to solar sails.

Today, Jun Chen from Fudan University in China and a few pals demonstrate the counterintuitive result that photons can pull things too. In other words, they've worked out how to generate a backward pulling force from a forward propagating beam.

Chen and buddies say this is possible when the system meets two conditions. First, it works only for beams in which the momentum in the direction of propagation is small, as is the case for beams that merely glance off an object. Second, the photons must simultaneously excite several multipoles within the particle, which scatter the beam.

If the scattering angle is just right, the total momentum in the direction of propagation can be negative, meaning the particle is pulled back towards the source and the light becomes a tractor beam.

This must not be confused with various "optical tweezer" type mechanisms in which particles trapped in a beam follow the intensity gradient of the light. In this case, the particles always reach some point of equilibrium where the intensity reaches a maximum.

Chen and co's new force works when there is no gradient. Given the chance, their tractor beam will pull a particle all the way back to the source.

That's a handy additional tool in the nanomanipulator's box of tricks. "This may open up new avenues for optical micromanipulation, of which typical examples include transporting a particle backward over a long distance and particle sorting," say Chen and co.

This is a theory paper so there's one piece of the puzzle left to fit. All they have to do now is demonstrate that their tractor beam works.

Ref: : Backward Pulling Force From A Forward Propagating Beam"

Note: You can read the scientific paper at

Video of China's 120-Ton Liquid Oxygen/Kerosene Rocket Engine Test

The video may load slowly. Please be patient. The action starts 35 seconds (after the water release) into the video. It is one of the most impressive videos that I have seen.

[video]http://video.sina.com.cn/v/b/47542992-1738778381.html[/video]

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"China Developing New Rocket Engines
January 10, 2011, 10:22 pm


Photo Credit: CASC (China Aerospace Science & Technology Corp.)

China is advancing its space capabilities by developing staged combustion, an engine technology that is likely to offer greater performance for the Long March 6 and 7, two of a family of launchers that the country will field around the middle of the decade.

The smaller of the two, the Long March 6, may be the first to go into service, beating the flagship third member of the family, the Long March 5 heavy launcher.

A new 18-metric-ton-thrust engine “is a high-altitude liquid oxygen and kerosene engine with a staged combustion cycle and has been indigenously designed by China,” says national space contractor CASC.

If successfully executed, this technology would offer a high specific impulse, a key measure of rocket performance that compares the duration and level of thrust with the mass of fuel consumed in generating it. The practical result should be a greater payload to orbit for a launcher of a given size. The improved performance will probably be essential for China’s next generation of launchers to be competitive as the technology becomes increasingly common in the future.

As a liquid-fuel engine, the powerplant has limited meaning for China’s military capabilities. Modern missiles generally have solid propellants. But the development underscores the country’s ability to catch up with advanced foreign aerospace technology.

It can be assumed that development of the staged-combustion engine is going well, because CASC would not discuss a problem-ridden program that had hitherto received minimal attention, and because two rocket-building subsidiaries, SAST and CALT, are speaking optimistically of getting the related launchers into service within three or four years.

Shanghai-based SAST says its development of the Long March 6 is progressing smoothly and that the light launcher may become operational before the Long March 5.

The Long March 6 will be able to loft 1,000-kg. (2,200-lb.) payloads to an orbit of 600 km. (370 mi.) altitude, says SAST Vice President Meng Guang. The first launch of the Long March 5 heavy rocket is due in 2014 after a development program that began in 2007. Development of Long March 6 began in 2009, exploiting engines and stage modules already designed for the Long March 5.

The core of Long March 6 will use the standard 3.35-meter (11-ft.) diameter of the current Long March series, Meng and other SAST officials say. That means it will be based on the K3 stage module, the larger of two kerosene-fueled modules that SAST and CALT are developing for the launcher family.

A scheme for the family discussed in 2007 suggested that the smaller of its three launchers—now identified as Long March 6—would be based on the smallest, 2.25-meter-dia. module, K2, but the plan has obviously changed. The modules can serve as boosters or core stages.

Despite the rise in diameter, the first stage of Long March 6 will presumably be propelled by the single YF100 engine generating 120 metric tons (265,000 lb.) of thrust previously associated with the light rocket. The upper stage will have a smaller engine, says Meng, without giving details. CALT Vice President Hao Zhaoping has said that the medium-heavy Long March 7 will use an 18-ton engine for its second stage.

Since CASC says the staged-combustion engine will have a thrust of 18 tons and will be used on “new-generation launch vehicles,” it should be the powerplant for the second stages of Long March 6 and 7. One foreign rocket engineer calculates that the Long March 7 would need two of the 18-ton engines for its second stage.

The Long March 5 has core stages fed by liquid hydrogen and liquid oxygen, another technology route to high specific impulse. Kerosene-fueled modules with YF100s serve as its boosters.

Staged combustion avoids the usual waste of fuel or oxygen used to drive the pumps in an engine with the conventional gas-generator cycle. To avoid overheating, the mixture in that process in any liquid-fuel rocket is deliberately not optimal. It must have either too much oxygen or too much fuel, one of which is therefore partly wasted as the exhaust is dumped overboard.

In staged combustion, that still-usable exhaust is instead fed into the main combustion chamber, driving up pressure and burning a second time to maximize impulse from the available tankage. The principle sounds simple, but in practice it presents great challenges in handling the hot, high-pressure exhaust. Staged combustion engines in service include the Russian RD-180, used on the Atlas V, and the Space Shuttle Main Engine.

Chinese engineers probably chose to use the technology first in a smaller engine because high specific impulses in upper stages have the greatest effect on payload, and because a smaller engine would be easier to develop. The foreign engineer estimates that the engine will offer 15-20% higher specific impulse than an otherwise equivalent kerosene engine, and 10-15% greater payload to low Earth orbit, although another rocket propulsion specialist, from the U.S., thinks that with only a second stage using staged combustion, the payload advantage is likely to be 5-10%.

It is not known whether the Chinese engineers have chosen an oxygen- or kerosene-rich mixture for the pre-combustion. The former has advantages but is considered harder to develop.

The Chinese staged-combustion engine “adopts many advanced technologies, such as forced start and optimal stage transfer,” says CASC, giving neither the engine’s name nor the identity of the institute that developed it. The engine can operate for a long time, it adds. “It can regulate the thrust mixture ratio, supply a working medium for tank pressurization and provide a power supply for the servomechanism,” the hydraulics.

Optimal stage transfer implies that the engine is just the right size to propel its stage. Forced starting may mean restarting, which an upper-stage engine will often have to do, while the regulated mixture ratio implies that the Chinese powerplant has an advanced capability to accept propellants at imperfect ratios—maximizing its use of tankage even if the oxygen supply is reduced by boiling off.

A second U.S. rocket engineer interprets the reference to servomechanism power as meaning that the engine feeds high-pressure kerosene from the pump outlet, uses it as a working fluid in the actuators, and then sends it back for combustion. Several Russian engines have such a function, instead of a completely separate hydraulic system.

The design of the engine in general shows signs of Russian practice. It is not known whether that is because Russia has helped China with the program or because Chinese engineers simply like Russian features.

Manufacture of the Long March 7 has not yet been assigned to either SAST (Shanghai Academy of Spaceflight Technology) or CALT (China Academy of Launch Vehicle Technology), both subsidiaries of CASC (China Aerospace Science & Technology Corp.)."

Note: Thank you to "Marchpole" for the post.

World's first 660 KV DC transmission system sends power across China



"World's first 660 KV transmission system sends power across China
2011-02-28 16:15:32


Photo taken on Feb. 28, 2011 shows a transformer site for the 660 kV DC power transmission line in Yinchuan, capital of northwest China's Ningxia Hui Autonomous Region. The world's first 660 kV DC power transmission line, linking Ningxia with east China's Shandong Province, was officially put into operation on Monday. (Xinhua/Wang Peng)


Technicians work at a power plant in Yinchuan, capital of northwest China's Ningxia Hui Autonomous Region, on Feb. 28, 2011. (Xinhua/Wang Peng)


Photo taken on Feb. 28, 2011 shows a transformer site for the 660 kV DC power transmission line in Yinchuan, capital of northwest China's Ningxia Hui Autonomous Region. (Xinhua/Wang Peng)

YINCHUAN, Feb. 28 (Xinhua) -- The world's first 660-kilovolt direct current power transmission system began to supply energy from northwest China's Ningxia Hui Autonomous Region to the eastern Shandong Province on Monday.

The 10.4-billion-yuan (1.58 billion U.S. dollars) project is part of China's west-east power transmission program.

The cable system has a current-carrying capacity of 4 million kilowatts of electricity traveling over a distance of 1,333 km through five provinces and regions.

To generate the same amount of electricity, about 13 million tons of coal would be needed and 650,000 20-ton trucks to deliver the coal.

Therefore, the cable system not only eases Shandong's energy needs, but also helps relieve traffic pressures on the roads.

Cui Jifeng, general manager of Ningxia Power Co., a subsidiary of the China Power Grid Co., said the system was built to supply hydropower generated on the upper reaches of the Yellow River, as well as thermal power produced in Ningxia to coastal Shandong.

The system was independently designed, produced, built and tested by Chinese companies, he noted.

China's coal resources are mainly based in the west and north, which are economically underdeveloped compared with the east. The west-east power transmission program was begun in 2000.

The State Grid Corp. plans to build six cable systems, including three west-east facilities and three north-south systems, between 2011 and 2015.

For coal-rich provinces, the cables will make their coal mines more profitable, said Pan Jiazheng, academician of the Chinese Academy of Sciences.

The revenues from mining and delivering 13 million tons of coal by truck are about 2.59 billion yuan, while those of transmitting electricity generated by an equal amount of coal can be 6.5 billion yuan, according to Pan."

Re: Every rail line serves a particular city. What waste are you talking about?

Originally Posted by pugachev_diver View Post
Cant't name it right off my head at this moment, but I'm sure if you go online, you can easily find 10 different articles talking about this problem.

quote Martian;140928]Spare me your "sour grapes.

Click to expand...

¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬Martian , In the wake of the revelation in the stupendous losses made by China rail over recent years

"........... China's Ministry of Railways (MOR) is leading HSR construction. According to a report from the National Audit Office, the Ministry of Railways (MOR) was 1.3 trillion yuan ($195.50 billion) in debt in 2009, with 854.8 billion yuan ($128.21 billion) in short-term debt and 448.6 billion yuan ($67.33 billion) in long-term debt.
A report from China Minsheng Bank showed that the rapidly growing debt pushed up the interest that MOR had to pay, rising to 40 billion yuan ($6 billion) in 2009. China was expected to extend its HSR network to 16,000 kilometers by the end of 2010, at a cost of more than 2.6 trillion yuan ($390 billion), about the same cost as 1,300 Boeing 747 airliners.
Despite the government's generous funding, the HSR network won't turn a profit until 2030. What's more, no one can guarantee whether the government will benefit from the HSR sector afterwards........."

Therefore, one can hardly call "Pugachev Divers" suggestion for a re-evaluation as one motivated by "sour grapes"

Opening in 2008, the Beijing-Tianjin Intercity Railway lost more than 700 million yuan ($105 million) in its first year of operation. This line transported 18.7 million passengers over that period, only 62.3 percent of the expected number............
According to the China Daily



...............But many travelers cannot afford the tickets, causing a waste of transport capacity.
According to a report in the Shanghai-based Oriental Morning Post on Tuesday, hundreds of soft berths on bullet trains between Chengdu and Shanghai will be vacant, although cheaper tickets have sold out.
He Jianzhong said this year the situation had pushed many passengers, who used to ride home by slow trains because of the cheap tickets, onto long-distance buses.
This extra traffic will add pressure to the road transport system during the travel peak season, He said.
The Ministry of Transport estimated that a record high of 2.6 billion bus passenger trips will be made during the peak time between Jan 19 and Feb 27, an increase of 11.6 percent on the same period last year.
The transport sector plans to increase capacity to handle the extra traffic. A total of 840,000 buses, including 70,000 added this year, will hit the road during the travel peak, making 2.4 million road trips a day, he said.

While giving away some passengers to road transport, the high-speed railways, at the same time, have attracted more affluent travelers from the airlines.
Wang Changshun, deputy head of the Civil Aviation Administration of China, told a conference on Tuesday that the fast trains have forced some airlines to cancel short-distance flights along high-speed rail lines.

For example, the Wuhan-Guangzhou high-speed railway, where every few minutes trains zip between the two cities via Changsha, capital of Central China's Hunan province, has carried 20.6 million passengers in the year since its opening in December 2009.

During that period the number of flights between Changsha and Guangzhou has been cut from an average of 11.5 flights a day to three flights a day, he said.
Hainan and Shenzhen airlines decided to withdraw from the market, leaving only China Southern Airlines carrying the three daily flights, Wang said.

The ticket price for those flights also dropped by 15 percent to attract travelers, but still the number of passengers flying between Changsha and Guangzhou dropped by 48 percent to 390,000 during 2010, he said.

The opening of the Beijing-Shanghai high-speed line next year will be another blow to the air transport industry," Wang said, without forecasting how serious the impact will be.
Airlines have been urged to cut costs, reduce delays and seek cooperation opportunities with high-speed railways. "
Tan Zongyang contributed to this story.
China Daily

I dont think it was China rails intent to force people to use buses but its happening.

The railways will find out what is the proper mix of seat to win passengers from the airlines as well as back from the buses.
Wages are rising and that helps too.

Molecular motor design breakthrough - first molecular piston capable of self-assembly



"Molecular motor design breakthrough - first molecular piston capable of self-assembly
March 04, 2011

French researchers from CNRS and the Universite de Bordeaux, in collaboration with a Chinese team, have developed the first molecular piston capable of self-assembly. Their research represents a significant technological advance in the design of molecular motors. Such pistons could, for example, be used to manufacture artificial muscles or create polymers with controllable stiffness.


a) side view of the crystal structures of the host-guest complex 1É8 with single helix 1 in tube representation and rod 8 in CPK representation. b) Top view and c) side view of 1É8 with both rod and helix in CPK representation. Carbon atoms of the thread are shown in grey, nitrogen atoms in light blue, oxygen atoms in red and hydrogen atoms in white. Single helix 1 is shown in red. Isobutyl side chains and included solvent molecules have been removed for clarity.



Dynamic assembly is a powerful fabrication method of complex, functionally diverse molecular architectures, but its use in synthetic nanomachines has been hampered by the difficulty of avoiding reversible attachments that result in the premature breaking apart of loosely held moving parts. We show that molecular motion can be controlled in dynamically assembled systems through segregation of the disassembly process and internal translation to time scales that differ by four orders of magnitude. Helical molecular tapes were designed to slowly wind around rod-like guests and then to rapidly slide along them. The winding process requires helix unfolding and refolding, as well as a strict match between helix length and anchor points on the rods. This modular design and dynamic assembly open up promising capabilities in molecular machinery.

Living organisms make extensive use of molecular motors in fulfilling some of their vital functions, such as storing energy, enabling cell transport or even moving about in the case of bacteria. Since the molecular layouts of such motors are extremely complex, scientists seek to create their own, simpler versions. The motor developed by the international team headed by Ivan Huc , CNRS researcher in the “Chimie et Biologie des Membranes et des Nanoobjets” Unit, is a “molecular piston”. Like a real piston, it comprises a rod on which a moving part slides, except that the rod and the moving part are only several nanometers long.

More specifically, the rod is formed of a slender molecule, whereas the moving part is a helix-shaped molecule (both are derivatives of organic compounds especially synthesized for the purpose). How can the helicoidal molecule move along the rod? The acidity of the medium in which the molecular motor is immersed controls the progress of the helix along the rod: by increasing the acidity, the helix is drawn towards one end of the rod, as it then has an affinity for that portion of the slender molecule. By reducing the acidity, the process is reversed and the helix goes in the other direction.

This device has a crucial advantage compared to existing molecular pistons: self-assembly. In previous versions, which take the form of a ring sliding along a rod, the moving part is mechanically passed onto the rod with extreme difficulty. Conversely, the new piston is self-constructing: the researchers designed the helicoidal molecule specifically so that it winds itself spontaneously around the rod, while retaining enough flexibility for its lateral movements.

By allowing the large scale manufacturing of such molecular pistons, this self-assembly capacity augurs well for the rapid development of applications in various disciplines: biophysics, electronics, chemistry, etc. By grafting several pistons together end-to-end, it could be possible, for example, to produce a simplified version of an artificial muscle, capable of contracting on demand. A surface bristling with molecular pistons could, as and when required, become an electrical conductor or insulator. Finally, a large-scale version of the rod on which several helices could slide would provide a polymer of adjustable mechanical stiffness. This goes to show that the possibilities for this new molecular piston are (almost) infinite.

a) Assembly of an irreversible axis and a ring sliding along the latter.
b) reversible assembly of a propeller wound slowly around an axis and then quickly slip on it. (© Yann Ferrand / CNRS)

Notes:

(1) Beijing National Laboratory for Molecular Sciences
(2) His team is part of the European Institute of chemistry and biology.

References:

Helix-Rod Host-Guest Complexes With Much Faster Than Shuttling Rates Disassembly. Quan Gan, Yann Ferrand, Chunyan Bao, Brice Kauffmann, Axelle Grélard, Hua Jiang, Ivan Huc. Science. March 4, 2011.

Click to expand...

"

delft said:

The railways will find out what is the proper mix of seat to win passengers from the airlines as well as back from the buses.
Wages are rising and that helps too.

Click to expand...

Exactly China won't be poor forever. I am not surprise at the condescending comment .20 years ago when China build Highway system the same sour grape comment show up ."The highway is empty there is hardly any car why build highway"

Fast forward seem like China can't built enough highway. Who would ever guess that China's car production reached 11 million. Build first then they will use the highway. That show dynamism of new China a calculated risk. When you star nickel and diming a project nothing wll ever get built

Anyway it is wrong to see rail income only from the sale of passenger ticket , The real estate along the rail line will become gold . New city, industrial estate will sprout along the railway line generating economy activity more than paid for the cost of building the rail line Not to mention facilitate the move of industry to the inland of China