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Strong evidence for d-electron spin transport at room temperature

WOW! Great non-local signals, at room temperature!!! Spin transistor on the way finally!? (of course electric field gate controlled is fundamental) See more about the "quest" for the spin transistor here: http://spectrum.ieee.org/semiconductors/processors/the-quest-for-the-spin-transistor

It has been known for a century that electromagnetic fields can transport not only energy and linear momentum but also angular momentum. However, it was not until twenty years ago, with the discovery in laser optics of experimental techniques for the generation, detection and manipulation of photons in well-defined, pure orbital angular momentum (OAM) states, that twisted light and its pertinent optical vorticity and phase singularities began to come into widespread use in science and technology. We have now shown experimentally how OAM and vorticity can be readily imparted onto radio beams. Our results extend those of earlier experiments on angular momentum and vorticity in radio in that we used a single antenna and reflector to directly generate twisted radio beams and verified that their topological properties agree with theoretical predictions. This opens the possibility to work with photon OAM at frequencies low enough to allow the use of antennas and digital signal processing, thus enabling software controlled experimentation also with first-order quantities, and not only second (and higher) order quantities as in optics-type experiments. Since the OAM state space is infinite, our findings provide new tools for achieving high efficiency in radio communications and radar technology.

and how can we use this?

from the abstract: "Using a novel imaging and analysis technique on experimental data we estimated pheromone concentrations at all spatial positions in the experimental arena and at different times. Then we derived the response function of individual ants to pheromone concentrations by looking at correlations between concentrations and changes in speed or direction of the ants." [...] "agent based simulations based on the Weber's Law response function determined experimentally produced results compatible with those reported in the literature and reproduced the formation of trails."

Nice article!

More details in the linked pdf file.. a low pressurized tube with pods floating on air cushions together with EM propulsion and braking.. cool, but probably not going to be build any day soon

It would be great indeed, but even though the cost of the high speed train is a factor 10x higher, the prototype nature and hence relatively lower TRL of this system will probably not have it favoured. Best chance is that he develops a working prototype, one that might not even transport humans at the moment and for short distances, then maybe the project can take off

Actually, he was talking about a prototype: "I am somewhat tempted to at least make a demonstration prototype," Musk said in a conference call with reporters on Monday. "Perhaps I'll create a sub-scale version that's operating, and then hand it over to somebody else." "I think I'll probably end up doing that," he said. http://allthingsd.com/20130812/elon-musk-will-likely-build-his-own-hyperloop-prototype/

Another underestimated source of CO2, are turbulent waters. "The stronger the turbulences at the water's surface, the more CO2 is released into the atmosphere. The combination of maps and data revealed that, while the CO2 emissions from lakes and reservoirs are lower than assumed, those from rivers and streams are three times as high as previously believed." Alltogether the emitted CO2 equates to roughly one-fifth of the emissions caused by humans. Yet more stuff to model...

Nasia, I thought about your statement carefully - and I cannot agree with you. Water is not a greenhouse gas. It is instead a liquid. Also, I can't believe you keep feeding the troll! :-P But on a more topical note: I think it is an over-simplification to call water a greenhouse gas - water is one of the most important mechanisms in the way Earth handles heat input from the sun. The latent heat that you mention actually cools Earth: solar energy that would otherwise heat Earth's surface is ABSORBED as latent heat by water which consequently evaporates - the same water condenses into rain drops at high altitudes and releases this stored heat. In effect the water cycle is a mechanism of heat transport from low altitude to high altitude where the chance of infrared radiation escaping into space is much higher due to the much thinner layer of atmosphere above (including the smaller abundance of greenhouse gasses). Also, as I know you are well aware, the cloud cover that results from water condensation in the troposphere dramatically increases albedo which has a cooling effect on climate. Furthermore the heat capacity of wet air ("humid heat") is much larger than that of dry air - so any advective heat transfer due to air currents is more efficient in wet air - transporting heat from warm areas to a natural heat sink e.g. polar regions. Of course there are also climate heating effects of water like the absorption of IR radiation. But I stand by my statement (as defended in the above) that rain cools the atmosphere. Oh and also some nice reading material on the complexities related to climate feedback due to sea surface temperature: http://journals.ametsoc.org/doi/abs/10.1175/1520-0442(1993)006%3C2049%3ALSEOTR%3E2.0.CO%3B2

I enjoy trolling conversations when there is a gain for both sides at the end :-) . I had to check upon some of the facts in order to explain my self properly. The IPCC report states the greenhouse gases here, and water vapour is included: http://www.ipcc.ch/publications_and_data/ar4/wg1/en/faq-2-1.html Honestly, I read only the abstract of the article you posted, which is a very interesting hypothesis on the mechanism of regulating sea surface temperature, but it is very localized to the tropics (vivid convection, storms) a region of which I have very little expertise, and is difficult to study because it has non-hydrostatic dynamics. The only thing I can comment there is that the authors define constant relative humidity for the bottom layer, supplied by the oceanic surface, which limits the implementation of the concept on other earth regions. Also, we may confuse during the conversation the greenhouse gas with the Radiative Forcing of each greenhouse gas: I see your point of the latent heat trapped in the water vapour, and I agree, but the effect of the water is that it traps even as latent heat an amount of LR that would otherwise escape back to space. That is the greenhouse gas identity and an image to see the absorption bands in the atmosphere and how important the water is, without vain authority-based arguments that miss the explanation in the end: http://www.google.nl/imgres?imgurl=http://www.solarchords.com/uploaded/82/87-33833-450015_44absorbspec.gif&imgrefurl=http://www.solarchords.com/agw-science/4/greenhouse--1-radiation/33784/&h=468&w=458&sz=28&tbnid=x2NtfKh5OPM7lM:&tbnh=98&tbnw=96&zoom=1&usg=__KldteWbV19nVPbbsC4jsOgzCK6E=&docid=cMRZ9f22jbtYPM&sa=X&ei=SwynUq2TMqiS0QXVq4C4Aw&ved=0CDkQ9QEwAw

Imagine a material that only admits thermal conduction for certain temperatures. Martin Maldovan from Georgia Tech holds a tiny thermoelectric device that turns cold on one side when current is applied. Recent research has focused on the possibility of using interference effects in phonon waves to control heat transport in materials. These are exciting news (see Nature Materials paper here http://www.nature.com/nmat/journal/v14/n7/full/nmat4308.html). Heterostructure research lead to outstanding new possibilities when applied to electronic transport (e.g. in quantum well and quantum dots) and to photonics (e.g. Quantum Cascade Laser tunnable lasers). Apparently the time has come to see selective thermal control in this way! Truly exciting!!

what a ACT's exercise should look like...

Maybe, you should propose this exercise to the team. You'll see there is not much imagination, unless, you consider imagination equals craziness (bullshit things ... and the too common blah blah in the act). I think this concept is an imaginative credible concept. "anything we might ever see" explains it well.

well, the article is not very detailed so it can be only "du vent" ! did they actually try if such an airplane can fly ??? what about the engine ??? i find the solar impulse (see post below) much more eco-friendly !!! I agree with Leopold that it's quite boring and stays in the mainstream of the production. I'm sure we can do much better !!! What about some really useful things like pills against the flight sickness, and some really good food in the plane ? haha not soon to happen with all the cost reduction. The future of air transport will be a plane without seats, stewards and perhaps even without pilot !!!

NASA aims to "create a healthy private-sector competition for transport to the space station". Through this the development of space tourism is enforced and an increase in the number of rocket launches should be expected. 

University Alliance for Low Carbon Energy   Three universities, including Tsinghua University, University of Cambridge, and the Massachusetts Institute of Technology, have fostered up an alliance on November 15, 2009 to advocate low carbon energy and climate change adaptation The alliance will mainly work on 6 major areas: clean coal technology and CCS, homebuilding energy efficiency, industrial energy efficiency and sustainable transport, biomass energy and other renewable energy, advanced nuclear energy, intelligent power grid, and energy policies/planning. A steering panel made up of the senior experts from the three universities (two from each) will be established to review, evaluate, and endorse the goals, projects, fund raising activities, and collaborations under the alliance. With the Headquarters at the campus of Tsinghua University and branch offices at other two universities, the alliance will be chaired by a scientist selected from Tsinghua University.   According to a briefing, the alliance will need a budget of USD 3-5 million, mainly from the donations of government, industry, and all walks of life. In this context, the R&D findings derived from the alliance will find its applications in improving people's life.

Cilia are hairs driven by molecular motors. They are found in monocellular organisms, etc. If we can build such things artificially, we have micro-pumps etc. Any space usability?

carlo's distributed actuator study originally considered cilia as well as peristaltic motion if i remember right. i suppose you might still think about debris transport for digging applications. Originally there was an idea for thermal transport aswell which, it turns out, was bollocks.

You guys could like this....

Combined method of construction and transportation for access to space of distributed heavyweight cargo and personnel with safe, economical and renewable characteristics.

Nonradiative resonant energy transfer in optimized QD-QW systems may provide a solar energy conversion approach with a viable tradeoff with the bottlenecks of charge carrier generation and/or transport to/in electrodes faced by excitonic solar cells.

We find that the high thermal conductivity of carbon nanotubes remains intact under severe structural deformations while the corresponding electrical resistance and thermoelectric power show compromised responses. Similar robust thermal transport against

Doesn't really sound sexy, but this is of utmost importance for next generation grids for renewable energy.

I agree on the significance indeed - a small boost also for my favourite Desertec project ... Though their language is a bit too "grandiose": "ABB has successfully designed and developed a hybrid DC breaker after years of research, functional testing and simulation in the R&D laboratories. This breaker is a breakthrough that solves a technical challenge that has been unresolved for over a hundred years and was perhaps one the main influencers in the 'war of currents' outcome. The 'hybrid' breaker combines mechanical and power electronics switching that enables it to interrupt power flows equivalent to the output of a nuclear power station within 5 milliseconds - that's as fast as a honey bee takes per flap of its wing - and more than 30 times faster than the reaction time of an Olympic 100-meter medalist to react to the starter's gun! But its not just about speed. The challenge was to do it 'ultra-fast' with minimal operational losses and this has been achieved by combining advanced ultrafast mechanical actuators with our inhouse semiconductor IGBT valve technologies or power electronics (watch video: Hybrid HVDC Breaker - How does it work). In terms of significance, this breaker is a 'game changer'. It removes a significant stumbling block in the development of HVDC transmission grids where planning can start now. These grids will enable interconnection and load balancing between HVDC power superhighways integrating renewables and transporting bulk power across long distances with minimal losses. DC grids will enable sharing of resources like lines and converter stations that provides reliability and redundancy in a power network in an economically viable manner with minimal losses. ABB's new Hybrid HVDC breaker, in simple terms will enable the transmission system to maintain power flow even if there is a fault on one of the lines. This is a major achievement for the global R&D team in ABB who have worked for years on the challeng

TU/e is participating in the new Cruiser class of the World Solar Challenge. This competition entails building an eco friendly family car (instead of a racer) to prove that solar powered transportation is possible. Actually this car produces more solar power than it needs and has a range of 300+ km.

For 11 years, Henley & Partners has published the Visa Restrictions Index, giving unprecedented and inimitable insight into the development of visa policies over time. It is the only Index produced in collaboration with the International Air Transport Association, which maintains the world's largest database of travel information.

A "four-wheel drive car" less than one billionth the length of an average SUV has been built and operated by researchers in the Netherlands and Switzerland.

"Molecular machines are common in nature. Motor proteins, for example, can move along a surface to transport molecular-sized cargo and are often used to build structures within living cells. " reminds me of the fantastic movie on what happens inside a cell ...

Charged like your electric toothbrush by lowering the receiving coils to 4cm above the ground.

nice; there are similar trials ongoing a bit all over; there is one I know of in Mannheim, where i think they have quick charging coils at each stop to reduce the battery mass they need to carry; I have seen a demonstration of this in Kyoto university about 13 years ago on a normal car - even one where they had an entire road equipped with these chargers and tested with charging as you go , charing at traffic stops, parking etc ....

Interesting report on water transport in deep see fault lines. Subduction can suck huge quantities of water of water underground where friction and pressure heat it up causing the mantle to partly melt which leads to volcanic activities around the fault zones. Not all the water would make it back up, leading to the possibility that there might be large quantities of water stored within the earths crust.