China Science & Technology Forum

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Money can not buy intelligence,too simple.

 

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Money can not buy intelligence,too simple.

too naive

americans are buying our talents

 

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too naive

americans are buying our talents

Too funny
What talents,assistants whole working life in labs?

 

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too naive

americans are buying our talents

Stealing，not buying，for these talents are paid far less than their true worth or value。

 

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Too funny
What talents,assistants whole working life in labs?

too sad
it looks like all your acquaintances are a lot of lab assistant level of people in your life, may be including yourself!

 

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It is probable that，by the end of this year，foreign smartphone brands will have less than 20% of the Chinese market by numbers。

Xiaomi muscles past Apple to take sixth place in China’s smartphone market as Samsung stays on top

By Kaylene Hong

TNW Asia - Asia's Technology Blog about Internet Life, Business and Culture. Part of The Next Web Network.

Chinese smartphone manufacturer Xiaomi has been on a roll despite launching its first device only as recently as 2011 — it has officially overtaken Apple in the Chinese market.

The latest figures were conveyed to TNW by Canalys, an independent analyst firm, which noted that Xiaomi shipped a total of 4.4 million smartphones in China during the second quarter of 2013, inching above Apple which shipped 4.3 million units and knocking it to the seventh position. Last quarter, Apple managed to occupy the fifth spot in China’s smartphone market.

Samsung still took the lead in China in Q2 2013 with 15.5 million smartphones shipped to make up for a market share of 17.6 percent.

Despite only selling its phones in mainland China, Hong Kong and Taiwan, Xiaomi has been garnering success by inspiring the loyalty of many consumers. Its competitively priced phones are sold in batches that, when released in phases, regularly sell out fast, often within half an hour.

The latest figures come as Xiaomi recently unveiled its $130 Hongmi phone, the lowest-priced in its range, which has received an overwhelming response so far. According to a Donews report, pre-orders for the phone on social networking site Qzone exceeded a jaw-dropping 5 million units within three days. The phone will go on sale from August 12 onward.

The up-and-coming company has been compared to Apple on a regular basis, with some even criticizing it for being an Apple clone. However, it seems that consumers are happy to flock to the lower-priced Xiaomi smartphones instead of high-end iPhones, proven by its success so far. This could make it even harder for Apple to recapture some of its lost market share in China — despite rumors of a lower-priced iPhone, it could be too little, too late.

 

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too sad
it looks like all your acquaintances are a lot of lab assistant level of people in your life, may be including yourself!

Don't bother to talk about me and I am not saying about you.
I know one come from Princetown University who graduated from Qinghua and now working like I said for his boss and he and others told me what so called talented Chinese do.Lab assistant a good occupation any way.
OK,here is a talent who speak fluent mandarin and still working in labs,but not as an assistant:

 

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Don't bother to talk about me and I am not saying about you.
I know one come from Princetown University who graduated from Qinghua and now working like I said for his boss and he and others told me what so called talented Chinese do.Lab assistant a good occupation any way.
OK,here is a talent who speak fluent mandarin and still working in labs,but not as an assistant:

Good for your previous sarcasm!

the scientist when young! And much more of my respect when he delivered his award receiving speech in Putonghua!

He is still making great contribution in high energy physics and lately in his new findings on dark matters with his team!

 

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Stealing，not buying，for these talents are paid far less than their true worth or value。

Not just usa to where we lose our scientists. Hereunder is another example of the great discovery our people who can revolutionalse a commonly used storage device:

Chinese researchers discover new method to store 1,024,000 GB in a single DVD
06/24/2013 BY ADMIN

link

Most of us have probably moved on to using Blu-rays now, but the old DVD might have just received a big shot in the arm. And I mean big.

A bunch of Chinese researchers have discovered a new method that could theoretically allow a single DVD to store 1,000 terabytes (1,024,000 GB) of data. That’s a whole petabyte of storage in a medium that when it was first introduced was only capable of 4.7GB.

The DVD format was limited by the size of the laser, which Blu-ray eventually surpassed by using even smaller lasers — but that too hit a limit. According to Gizmodo‘s conveniently simplified rundown of the process, the researchers have developed a new method that uses two lasers that can cancel each other out, effectively creating smaller pits on the disk and increasing the amount of capacity.

But before you toss out the Blu-rays, note that it might be some time before this technology will reach the consumer level. While the data can be created, they still need to figure out a way to actually read it. Also, burning a 1,000TB disc sounds like it could take awhile.

More in detail here in Nauture Communications:

Three-dimensional deep sub-diffraction optical beam lithography with 9 nm feature size
Zongsong Gan, Yaoyu Cao, Richard A. Evans & Min Gu

http://www.nature.com/ncomms/2013/130619/ncomms3061/full/ncomms3061.html

 

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This kind of plants may provide solutions to messy and harmful oil spills

Credit: jiaoma.com

Structured cone arrays for continuous and effective collection of micron-sized oil droplets from water
http://www.nature.com/ncomms/2013/130806/ncomms3276/full/ncomms3276.html

Here an abstract:

Environmental protection agencies and the petroleum industry require effective methods to separate micron-sized oil droplets from water. However, for most existing separation methods, phase separation occurs in the oil–water mixture.

The remaining micron-scale oil droplets, which are not affected by phase separation, are difficult to handle with conventional methods on a large scale because of either a lack of separation ability or drawbacks in throughput capacity. Here we develop an oleophilic array of conical needle structures for the collection of micron-sized oil droplets, inspired by the collection of similar sized water droplets on conical cactus spines.

Underwater, these structures mimic cacti and can capture micron-sized oil droplets and continuously transport them towards the base of the conical needles. Materials with this structure show obvious advantages in micron-sized oil collection with high continuity and high throughput.

Affiliations
Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
Kan Li, Jie Ju, Zhongxin Xue, Jie Ma & Lei Jiang
Department of Chemistry, Tsinghua University, Beijing 100084, China
Lin Feng
College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
Song Gao
School of Chemistry and Environment, Beihang University, Beijing 100191, China
Lei Jiang



Also reported in the mass media hereunder:

Cactus 'points' the way for oil spill clean-up

Updated: 2013-08-07 15:45 ( Xinhua)

http://www.chinadaily.com.cn/china/2013-08/07/content_16877933.htm

BEIJING -- Inspired by prickly cacti, Chinese scientists have developed a new technique for removing oil from water, which could have applications in oil spill clean-up work.

An article published in the online scientific journal Nature Communications describes the study by Jiang Lei and his co-workers at the Institute of Chemistry, Chinese Academy of Sciences, whose creation of copper spike arrays have proved to be highly efficient in absorbing oil during experiments.

Jiang said the idea came from cacti needles, which can collect water by condensing moisture from the air and directing it to the root of the spines, an ability that keeps the plant hydrated in arid environments, like deserts.

Simulating cacti spines, researchers used substances with an affinity for oil, not water, to build conical spikes with a rough surface. These spikes have proven capable of catching micro-sized oil droplets in water.

Oil separation using such needle arrays has an efficiency rate of over 99 percent, and compared with conventional methods, our technique can be used continuously and is more environmentally friendly, Jiang told Xinhua.

Researchers expect that the technique could help clean water pollution caused by oil spills and be applied in industrial sectors, including those involved in oily industrial effluent disposal and tertiary oil recovery.




中国科学院 化学研究所
Institute of Chemistry, Chinese Academy of Sciences （ICCAS）

 

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Talking about braindrain, this Fudan University alumnus who is now working with a team of scientists at the Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Department of Biology and Department of Brain and Cognitive Sciences, MIT has made this important discovery in brain research:

Neuroscientists plant false memories in the brain
MIT study also pinpoints where the brain stores memory traces, both false and authentic.
Anne Trafton, MIT
July 25, 2013


The phenomenon of false memory has been well-documented: In many court cases, defendants have been found guilty based on testimony from witnesses and victims who were sure of their recollections, but DNA evidence later overturned the conviction.

In a step toward understanding how these faulty memories arise, MIT neuroscientists have shown that they can plant false memories in the brains of mice. They also found that many of the neurological traces of these memories are identical in nature to those of authentic memories.

“Whether it’s a false or genuine memory, the brain’s neural mechanism underlying the recall of the memory is the same,” says Susumu Tonegawa, the Picower Professor of Biology and Neuroscience and senior author of a paper describing the findings in the July 25 edition of Science.

MIT neuroscientists identified the cells (highlighted in red) where memory traces are stored in the mouse hippocampus.
IMAGE: STEVE RAMIREZ AND XU LIU

The study also provides further evidence that memories are stored in networks of neurons that form memory traces for each experience we have — a phenomenon that Tonegawa’s lab first demonstrated last year.

Neuroscientists have long sought the location of these memory traces, also called engrams. In the pair of studies, Tonegawa and colleagues at MIT’s Picower Institute for Learning and Memory showed that they could identify the cells that make up part of an engram for a specific memory and reactivate it using a technology called optogenetics.

Lead authors of the paper are graduate student Steve Ramirez and research scientist Xu Liu . Other authors are technical assistant Pei-Ann Lin, research scientist Junghyup Suh, and postdocs Michele Pignatelli, Roger Redondo and Tomas Ryan.

刘旭 博士 Dr LIU Xu, MIT
PhD Baylor College of Medicine
MS and BS: Fudan University



Seeking the engram

Episodic memories — memories of experiences — are made of associations of several elements, including objects, space and time. These associations are encoded by chemical and physical changes in neurons, as well as by modifications to the connections between the neurons.

Where these engrams reside in the brain has been a longstanding question in neuroscience. “Is the information spread out in various parts of the brain, or is there a particular area of the brain in which this type of memory is stored? This has been a very fundamental question,” Tonegawa says.

In the 1940s, Canadian neurosurgeon Wilder Penfield suggested that episodic memories are located in the brain’s temporal lobe. When Penfield electrically stimulated cells in the temporal lobes of patients who were about to undergo surgery to treat epileptic seizures, the patients reported that specific memories popped into mind. Later studies of the amnesiac patient known as “H.M.” confirmed that the temporal lobe, including the area known as the hippocampus, is critical for forming episodic memories.

However, these studies did not prove that engrams are actually stored in the hippocampus, Tonegawa says. To make that case, scientists needed to show that activating specific groups of hippocampal cells is sufficient to produce and recall memories.

To achieve that, Tonegawa’s lab turned to optogenetics, a new technology that allows cells to be selectively turned on or off using light.

For this pair of studies, the researchers engineered mouse hippocampal cells to express the gene for channelrhodopsin, a protein that activates neurons when stimulated by light. They also modified the gene so that channelrhodopsin would be produced whenever the c-fos gene, necessary for memory formation, was turned on.

In last year’s study, the researchers conditioned these mice to fear a particular chamber by delivering a mild electric shock. As this memory was formed, the c-fos gene was turned on, along with the engineered channelrhodopsin gene. This way, cells encoding the memory trace were “labeled” with light-sensitive proteins.

The next day, when the mice were put in a different chamber they had never seen before, they behaved normally. However, when the researchers delivered a pulse of light to the hippocampus, stimulating the memory cells labeled with channelrhodopsin, the mice froze in fear as the previous day’s memory was reactivated.

“Compared to most studies that treat the brain as a black box while trying to access it from the outside in, this is like we are trying to study the brain from the inside out,” Liu says. “The technology we developed for this study allows us to fine-dissect and even potentially tinker with the memory process by directly controlling the brain cells.”

Incepting false memories

That is exactly what the researchers did in the new study — exploring whether they could use these reactivated engrams to plant false memories in the mice’s brains.

First, the researchers placed the mice in a novel chamber, A, but did not deliver any shocks. As the mice explored this chamber, their memory cells were labeled with channelrhodopsin. The next day, the mice were placed in a second, very different chamber, B. After a while, the mice were given a mild foot shock. At the same instant, the researchers used light to activate the cells encoding the memory of chamber A.

On the third day, the mice were placed back into chamber A, where they now froze in fear, even though they had never been shocked there. A false memory had been incepted: The mice feared the memory of chamber A because when the shock was given in chamber B, they were reliving the memory of being in chamber A.

Moreover, that false memory appeared to compete with a genuine memory of chamber B, the researchers found. These mice also froze when placed in chamber B, but not as much as mice that had received a shock in chamber B without having the chamber A memory activated.

The researchers then showed that immediately after recall of the false memory, levels of neural activity were also elevated in the amygdala, a fear center in the brain that receives memory information from the hippocampus, just as they are when the mice recall a genuine memory.

These two papers represent a major step forward in memory research, says Howard Eichenbaum, a professor of psychology and director of Boston University’s Center for Memory and Brain.

“They identified a neural network associated with experience in an environment, attached a fear association with it, then reactivated the network to show that it supports memory expression. That, to me, shows for the first time a true functional engram,” says Eichenbaum, who was not part of the research team.

The MIT team is now planning further studies of how memories can be distorted in the brain.

“Now that we can reactivate and change the contents of memories in the brain, we can begin asking questions that were once the realm of philosophy,” Ramirez says. “Are there multiple conditions that lead to the formation of false memories? Can false memories for both pleasurable and aversive events be artificially created? What about false memories for more than just contexts — false memories for objects, food or other mice? These are the once seemingly sci-fi questions that can now be experimentally tackled in the lab.”

The research was funded by the RIKEN Brain Science Institute.

http://web.mit.edu/newsoffice/2013/neuroscientists-plant-false-memories-in-the-brain-0725.html

 

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An article of great interest and practical use：

A Semi-Floating Gate Transistor for Low-Voltage Ultrafast Memory and Sensing Operation

Peng-Fei Wang1,*,†, Xi Lin1, Lei Liu2, Qing-Qing Sun1,*, Peng Zhou1, Xiao-Yong Liu1, Wei Liu2, Yi Gong2, David Wei Zhang1,*
+ Author Affiliations

1State Key Laboratory of ASIC and System, School of Microelectronics, Fudan University, Shanghai, China.
2Oriental Semiconductor, Suzhou, China.
↵†Corresponding author. E-mail: pfw@fudan.edu.cn
↵* These authors contributed equally to this work.

ABSTRACTEDITOR'S SUMMARY

As the semiconductor devices of integrated circuits approach the physical limitations of scaling, alternative transistor and memory designs are needed to achieve improvements in speed, density, and power consumption. We report on a transistor that uses an embedded tunneling field-effect transistor for charging and discharging the semi-floating gate. This transistor operates at low voltages (≤2.0 volts), with a large threshold voltage window of 3.1 volts, and can achieve ultra–high-speed writing operations (on time scales of ~1 nanosecond). A linear dependence of drain current on light intensity was observed when the transistor was exposed to light, so possible applications include image sensing with high density and performance.

A Semi-Floating Gate Transistor for Low-Voltage Ultrafast Memory and Sensing Operation

 

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http://www.defence.pk/forums/china-far-east/269904-china-s-first-3d-bio-printer.html#post4617514

杭州电子科技大学
Hangzhou University of Electronic Science and Technology (or Hangzhou Danzi University)

Buildings of the Mathematics Department

Student Activities Center

Department of Robotics and Automation

Wenyi Campus

Xiasha Campus

 

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China's Huawei takes aim at Cisco with SDN programmable switch

Huawei is embarking on a global campaign to promote the new product

By Michael Kan

August 8, 2013 04:29 AM ET

IDG News Service - Huawei Technologies is bringing its own "software-defined networking" switch globally in a bid to raise its profile and expand in a market dominated by Cisco.

The Chinese company unveiled Thursday its S12700 Agile switch series, calling it a next generation product designed for managing campus networks. It joins the industry trend toward software-defined networking (SDN), an emerging technology that aims to deliver programmable interfaces to network hardware.

With SDN, a company can better customize its campus network through software and application development, rather than rely on making manual changes to the hardware, or buying new equipment to upgrade the network, Huawei executives said on Thursday. The rise of cloud computing and BYOD (bring-your-own-device) at offices demands that vendors come up with better and more secure solutions to manage networks, they added.

"The Agile switch and network products we launched today can truly resolve the problems customers have in network development," said William Xu, CEO of Huawei's enterprise business group in an interview. "It's a revolutionary product."

Huawei's Agile switch is designed with its own Ethernet network processor that can handle different software tasks. The company claims its product will offer better performance over rival switches built with application-specific integrated circuit (ASIC) chips, but at a still affordable low price.



The S12700 Agile switch series will come in two models and will arrive globally in October.

Huawei is best known for supplying telecommunication equipment to carriers, but in early 2011 the company officially entered the enterprise market. Since then the company has released new server and storage products, and seen its sales from its enterprise business grow to US$1.9 billion in 2012.

The company plans to hire an additional 1,000 employees globally to add to its 20,000 staff devoted to the enterprise business. By 2017, Huawei wants its enterprise revenue to reach over US$10 billion.

Huawei hopes its newest product, the Agile switch series, will further pave the way for its enterprise business and become a flagship product, Xu said. Starting on Thursday, the company is starting a global campaign to promote the switch in countries such as Japan and the U.S.

The Chinese company will have to contend with Cisco, a major U.S. provider of network switches. So far about half of Huawei's enterprise sales have come from its home market, with the remainder coming from foreign markets, including the U.S., where it has sold storage, switch and router products.

"We have just entered the U.S. enterprise business, and we are still in the process of learning," he said. But Xu expects the company's Agile switch will also garner customers in the U.S.

China's Huawei takes aim at Cisco with SDN programmable switch - Computerworld

 

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5 August 2013

Nanosphere-patterned sapphire improves deep UV LED performance

Researchers in China have been developing nanopatterned-sapphire substrates (NPSS), achieved with nano-sphere lithography (NSL), as a basis for the production of superior aluminium gallium nitride (AlGaN) semiconductor material for deep ultraviolet (UV) light-emitting diodes (LEDs) [Peng Dong et al, Appl. Phys. Lett., vol102, p241113, 2013].

“We have demonstrated the first high-performance AlGaN-based deep UV-LEDs fabricated on NPSS that is prepared by NSL and wet etching,” says the team from Chinese Academy of Sciences’ Institute of Semiconductors, Tsinghua University, and State Key Laboratory for Artificial Microstructure and Mesoscopic Physics at Peking University

Proposed applications of deep UV LEDs include disinfection, sensing, water purification, bio-medical, and communication. It is also hoped that efficient deep UV LEDs would provide more energy efficient compact solutions compared with the present fragile and hazardous mercury vapor lamps. Improved material quality is key to achieving these aims.

Sapphire patterning was achieved by photolithography through a mask consisting of polystyrene nanospheres that were then removed using deionized water (Figure 1). The pattern in the developed photoresist was transferred to an underlying hard mask layer of 200nm silicon dioxide using inductively coupled plasma etch. Finally, the sapphire was wet etched using a mix of sulfuric and phosphoric acid solutions. The silicon dioxide was removed using hydrofluoric acid.

Figure 1. (a) Schematic of fabrication process flow to create nano-patterns on a sapphire substrate (NPSS). SEM images of the patterned photoresist (b) and wet-etched NPSS (c). Inset in Figure 1(c) shows line profile of patterns of NPSS by AFM measurement.

The pattern consisted of 230nm-deep concave triangular cones set in a hexagonal pattern of period 900nm. The unetched region between the cones was 400nm wide.

The growth of the UV LED epitaxial structure was through low-pressure metal-organic chemical vapor deposition (LP-MOCVD) with trimethyl-aluminium, trimethyl-gallium, and ammonia precursors, respectively, for the Al, Ga, and N species. The structure began with 25nm of low-temperature 550°C AlN, before the whole 4μm AlN template was completed at 1200°C in nitrogen-rich conditions.

The AlN was found to coalesce after only 3μm. This is much sooner than other epitaxial layer overgrowth (ELOG) techniques using micro-stripe patterning that only coalesce after 10μm growth. Atomic force microscopy (AFM) over 5μm x 5μm fields gave a root-mean-square roughness of 0.15nm. The AFM analysis also indicated a step-flow growth mode. X-ray analysis gave estimates for screw and edge dislocation densities of 1.6x107/cm2 and 1.2x109/cm2, respectively.

This AlN template material was used in further growth of the UV LED structure (Figure 2). The same structure was grown on flat sapphire with a 1μm AlN template layer. The n-AlGaN layer was found to have pure edge and mixed threading dislocation densities on NPSS and FSS substrates of ~1.6x109/cm2 and ~3.4x109/cm2, respectively. The reduced density layer on NPSS was attributed to the higher-quality AlN template. The superlattice regions were also designed to have dislocation filtering effects.

Figure 2. Deep UV LED structure.

Temperature-dependent photoluminescence studies at 10K and 300K suggested an internal quantum efficiency of 45% for the NPSS LED structure, compared with 28% for the FSS AlN template epitaxy.

The epitaxial materials were formed into 380μm x 380μm devices. Mesas for the devices were etched using inductively coupled plasma. The n-contact metal stack consisted of titanium/aluminium/titanium/gold annealed at 850°C in nitrogen. The p-contact was nickel/gold annealed in air at 500°C.

The chips were flip-chip mounted on silicon sub-mounts with gold-bump bonding. The majority of light in deep UV LEDs is expected to emerge through the sapphire substrate, since the p-GaN layer is absorbing of the radiation due to it having the narrowest bandgap in the structure. The device testing was performed with the sub-mounted chips attached to metal-core circuit boards with silver paste to improve heat dissipation.

The main electroluminescence (EL) peak occurred at 282nm with a weak shoulder peak near 330nm (Figure 3). It is thought that recombination in the electron-blocking layer was responsible for the shoulder peak. Hence, “further optimization of the electron-blocking layer is needed to suppress electron overflow into the p-cladding layer,” the researchers write.

Figure 3. (a) EL spectra and (b) LOP-I-EQE curves of deep UV LEDs grown on NPSS and FSS.

The light output power (LOP) at 20mA current (I) was 3.03mW with external quantum efficiency (EQE) of 3.45% for the NPSS-based device. This was almost double that of the FSS-based LED. The saturation LOP for the NPSS LED was 6.56mW at 60mA current. The FSS device saturated at 2.53mW with 50mA injection.

Since the internal quantum efficiency does not account for all the improvement in performance, the researchers believe that “the light scattering at the AlN/NPSS interface decreases the total internal reflection and the absorption in the p-GaN layer, and increases the photon’s escape opportunity from the sapphire backside.”

Nanosphere-patterned sapphire improves deep UV LED performance