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Thijs Versloot

Sulfur Graphene Oxides for high performance #EV batteries #Berkeley - 0 views

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    Test cell reaches 500Wh/kg and about a 1000 cycles. Graphene is excellent to use as it can handle the thermal expansion during charge cycles which normally destroy the cathodes and thereby degrade performance over time.
johannessimon81

Genetic modification for climate change (dutch) - 0 views

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    Engineering and improving great tits so they can better withstand climate change. By selectively breeding and genetically engineering the birds scientists try to keep the time when the birds produce offspring in sync with the changing availability of food sources in spring (mainly grubs).
Dario Izzo

Climate scientists told to 'cover up' the fact that the Earth's temperature hasn't rise... - 5 views

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    This is becoming a mess :)
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    I would avoid reading climate science from political journals, for a less selective / dramatic picture :-) . Here is a good start: http://www.realclimate.org/ And an article on why climate understanding should be approached hierarcically, (that is not the way done in the IPCC), a view with insight, 8 years ago: http://www.princeton.edu/aos/people/graduate_students/hill/files/held2005.pdf
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    True, but fundings are allocated to climate modelling 'science' on the basis of political decisions, not solid and boring scientific truisms such as 'all models are wrong'. The reason so many people got trained on this area in the past years is that resources were allocated to climate science on the basis of the dramatic picture depicted by some scientists when it was indeed convenient for them to be dramatic.
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    I see your point, and I agree that funding was also promoted through the energy players and their political influence. A coincident parallel interest which is irrelevant to the fact that the question remains vital. How do we affect climate and how does it respond. Huge complex system to analyse which responds in various time scales which could obscure the trend. What if we made a conceptual parallelism with the L Ácquila case : Is the scientific method guilty or the interpretation of uncertainty in terms of societal mobilization? Should we leave the humanitarian aspect outside any scientific activity?
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    I do not think there is anyone arguing that the question is not interesting and complex. The debate, instead, addresses the predictive value of the models produced so far. Are they good enough to be used outside of the scientific process aimed at improving them? Or should one wait for "the scientific method" to bring forth substantial improvements to the current understanding and only then start using its results? One can take both stand points, but some recent developments will bring many towards the second approach.
pandomilla

Super-material shrugs off molten metal - 0 views

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    Droplets already bounce off water-repellent surfaces, but scientists have engineered materials that speed up the bounce to repel water faster. Even the brief contact time between a surface and a droplet that bounces off it can allow water to freeze or collect on the surface and cause damage.
Athanasia Nikolaou

Nature Paper: Rivers and streams release more CO2 than previously believed - 6 views

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    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...
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    This could also be a mechanism to counter human CO2 emission ... the more we emit, the less turbulent rivers and stream, the less CO2 is emitted there ... makes sense?
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    I guess there is a natural equilibrium there. Once the climate warms up enough for all rivers and streams to evaporate they will not contribute CO2 anymore - which stops their contribution to global warming. So the problem is also the solution (as always).
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    "The source of inland water CO2 is still not known with certainty and new studies are needed to research the mechanisms controlling CO2 evasion globally." It is another source of CO2 this one, and the turbulence in the rivers is independent of our emissions in CO2 and just facilitates the process of releasing CO2 waters. Dario, if I understood correct you have in mind a finite quantity of CO2 that the atmosphere can accomodate, and to my knowledge this does not happen, so I cannot find a relevant feedback there. Johannes, H2O is a powerful greenhouse gas :-)
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    Nasia I think you did not get my point (a joke, really, that Johannes continued) .... by emitting more CO2 we warm up the planet thus drying up rivers and lakes which will, in turn emit less CO2 :) No finite quantity of CO2 in the atmosphere is needed to close this loop ... ... as for the H2O it could just go into non turbulent waters rather than staying into the atmosphere ...
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    Really awkward joke explanation: I got the joke of Johannes, but maybe you did not get mine: by warming up the planet to get rid of the rivers and their problems, the water of the rivers will be accomodated in the atmosphere, therefore, the greenhouse gas of water.
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    from my previous post: "... as for the H2O it could just go into non turbulent waters rather than staying into the atmosphere ..."
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    I guess the emphasis is on "could"... ;-) Also, everybody knows that rain is cold - so more water in the atmosphere makes the climate colder.
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    do you have the nature paper also? looks like very nice, meticulous typically german research lasting over 10 years with painstakingly many researchers from all over the world involved .... and while important the total is still only 20% of human emissions ... so a variation in it does not seem to change the overall picture
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    here is the nature paper : http://www.nature.com/nature/journal/v503/n7476/full/nature12760.html I appreciate Johannes' and Dario's jokes, since climate is the common ground that all of us can have an opinion, taking honours from experiencing weather. But, the same as if I am trying to make jokes for material science, or A.I. I take a high risk of failing(!) :-S Water is a greenhouse gas, rain rather releases latent heat to the environment in order to be formed, Johannes, nice trolling effort ;-) Between this and the next jokes to come, I would stop to take a look here, provided you have 10 minutes: how/where rain forms http://www.scribd.com/doc/58033704/Tephigrams-for-Dummies
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    omg
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    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
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    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
dejanpetkow

3D Holographic Power Point Presentation at ASE 2013 - 1 views

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    THIS is how the ACT should give its science coffees, and I am not referring to the fat stage or the guy's dress. Next time I'm attending this traditional ACT exercise I expect such a show!
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    Thats pretty cool indeed! I am for it in the next budget run! :) However, its technically not holographic though as this looks like a projection on Mylar film at 45 degrees from a bottom projector. It looks 3D and holographic as the background is transparent.
Isabelle Dicaire

Measuring height by connecting clocks - 2 views

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    They were able to compare the ticking rates of two optical clocks separated by 2000 km, with the objective of computing sea level based on the effect gravity has on the clock ticking rate. They did the experiment using glass optical fibers, but I wonder if we could one day do the same from orbit, to measure the gravitational field around Earth.
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    isn't this is effectively what pacome has been doing with his time for the last few years? e.g. http://arxiv.org/pdf/1308.6766v1.pdf also mentioning the ACES experiment
Beniamino Abis

Wanted: Volunteers for Yearlong Mock Mars Mission in Canadian Arctic - 2 views

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    Mars Society, which advocates for manned exploration of the Red Planet, has released its requirements for the six volunteers who will be expected to spend 12 months at the society's Flashline Mars Arctic Research Station on Canada's Devon Island, which is about 1,450 kilometers from the North Pole, beginning in July 2014. Crewmembers will spend most of their time doing science, studying things such as carbon release from the permafrost and human performance in extreme conditions. If they want to go outside their base, they'll have to wear a spacesuit. If something breaks, they're the ones who are going to have to fix it.
Tom Gheysens

New theory of synapse formation in the brain - 2 views

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    I have no idea if an algorithm based on this already exists, but it would certainly be a good one for autonomous AI, I think. I think an algorithm based on this should be able to select his own input parameters and reject them if they are not stimulated any further or integrate them in the algorithm if they are continiously stimulated... this could enable self learning, etc.
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    By steering the neuron's back to an intermediate activity level the mechanism probably optimizes their efficiency within the network (after all a neuron that fires all the time is just as useless as one that never fires).
Zivile Dalikaite

Amaze project aims to take 3D printing 'into metal age' - 1 views

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    The European Space Agency has unveiled plans to "take 3D printing into the metal age" by building parts for jets, spacecraft and fusion projects.
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    Metal Age sounds like some epic good time...
Thijs Versloot

Quantum #teleportation theory to be tested on the #ISS - 8 views

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    A theory-SuperDense quantum teleportation-posed by Hampshire College physics professor Herbert Bernstein will be tested on the International Space Station. Theoretical physicist Bernstein devised the SuperDense scheme more than a decade ago in his investigations of different ways to send a quantum state from one part of a laboratory to a remote station.
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    Anna could you have a closer look into this - we should at least know what they are up to, be able to explain if anybody asks ... I also somehow missed this one in the NIAC study descriptions ... maybe a good moment to have another look at these "This is the second NASA grant for SuperDense quantum teleportation. A grant awarded in 2010 through NASA Innovative Advanced Concepts (NIAC) investigated the viability of the theory and produced the world's first experimental demonstration. Surprising or seminal experiments have marked Bernstein's research career. This is the fourth time a major proposal has become reality; two of his experiments helped found new sub-fields of physics (neutron interferometry and entanglement for quantum information)."
annaheffernan

Cool new analytical solutions to Maxwells equations - 5 views

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    The solutions show light tied in knots
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    Really cool topic. Here a link to a paper from Leiden's quantum optics group from 2008 about knotted light (I was in that group at the time): http://www.nature.com/nphys/journal/v4/n9/abs/nphys1056.html
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    knot theory ... any volunteers?
johannessimon81

Solar Power Satellites: overview of NASA's former plans - 1 views

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    Nice link and clear overview! I like the point raised about 1000 man in space, even when including automation (as far as they could envision at the time). Now that is a future of the space industry and permanent habitation of near-earth orbits! In fact, I can envision just two reasons maybe, power and the hotel industry
Thijs Versloot

ISEE-3 Reboot Project - Recovering an satellite from deep space by crowdsourcing @Spac... - 3 views

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    "A band of space hackers and engineers are trying to do something never done before - recover a 36 year old NASA spacecraft from the grips of deep space and time. With old NASA documents and Rockethub crowdfunding, a team led by Dennis Wingo and Keith Cowing is attempting to steer ISEE-3, later rechristened ICE, the International Cometary Explorer, back into an Earth orbit and return it to scientific operations. Dennis says, 'ISEE-3 can become a great teaching tool for future engineers and scientists helping with design and travel to Mars'. Only 40 days remain before the spacecraft will be out of range for recovery. A radio telescope is available, propulsion designs are in hand and the team is hoping for public support to provide the small amount needed to accomplish a very unique milestone in space exploration
Thijs Versloot

9-year timelapse of how to build a fusion reactor #Wendelstein7X - 5 views

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    Looking forward to see what this amazing piece of engineering can do!
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    Whenever I see the complexity of fusion reactor design it makes me appreciate the simplicity of fission reactors even more. ;-D
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    Hope no one left their sandwich inside this time...
Thijs Versloot

Timelapse of a stellar explosion #IFLS - 2 views

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    An amazing video.. while science is still puzzled what actually happened
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    There's one very simple explanation I can think of...
johannessimon81

Entangled photons make a picture from a paradox - 3 views

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    Physicists have devised a way to take pictures using light that has not interacted with the object being photographed. This form of imaging uses pairs of photons, twins that are 'entangled' in such a way that the quantum state of one is inextricably linked to the other.
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    The actual article: http://www.nature.com/nature/journal/v512/n7515/full/nature13586.html ScienceDaily version: "Scientists photograph the Schrödinger's cat for the first time!"
Paul N

Wiring of retina reveals how eyes sense motion - 2 views

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    Basically neuroscientists discovered time delay neural networks. Guess we were right on track with AI back in the 70s.
Dario Izzo

The Micro: The First Truly Consumer 3D Printer by M3D LLC - Kickstarter - 4 views

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    We must get one of these. They had a goal of 50.000$ but got, instead more than 3,000,000$ !!
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    Really bad market analysis on their part...
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    https://www.kickstarter.com/projects/formlabs/form-1-an-affordable-professional-3d-printer?ref=live i think this is the one I was talking about the other day. ~3M$ from 100k$ target in 2012. I think I remembered it though cos they got sued for patent infringement and it was the first time kickstarter had been included in the lawsuit. I may even have posted the story on diigo...
Thijs Versloot

Sunlight to jet fuel - European collaboration SOLAR-JET produces first solar kerosene - 4 views

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    With the first ever production of synthesized "solar" jet fuel, the EU-funded SOLAR-JET project has successfully demonstrated the entire production chain for renewable kerosene obtained directly from sunlight, water and carbon dioxide (CO2), therein potentially revolutionizing the future of aviation. This process has also the potential to produce any other type of fuel for transport applications, such as diesel, gasoline or pure hydrogen in a more sustainable way.
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