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Solar power without solar cells: A hidden magnetic effect of light could make it possible

Solar power without solar cells: A hidden magnetic effect of light could make it possible
A dramatic and surprising magnetic effect of light discovered by University of Michigan researchers could lead to solar power without traditional semiconductor-based solar cells. The researchers found a way to make an "optical battery," said Stephen Rand, a professor in the departments of Electrical Engineering and Computer Science, Physics and Applied Physics. In the process, they overturned a century-old tenet of physics. "You could stare at the equations of motion all day and you will not see this possibility. Light has electric and magnetic components. "This could lead to a new kind of solar cell without semiconductors and without absorption to produce charge separation," Rand said. What makes this possible is a previously undetected brand of "optical rectification," says William Fisher, a doctoral student in applied physics. Rand and Fisher found that under the right circumstances and in other types of materials, the light's magnetic field can also create optical rectification. Related:  `test 1021

Beyond 'absolute zero' temperatures get hotter It sounds like a contradiction in terms but scientists have reached temperatures that go beyond absolute zero in a lab, and get hotter as they do so. Whereas we’re all aware of what happens when temperatures hit negative temperatures on the Fahrenheit and Celsius scales (hint: it gets really cold), the Kelvin scale is an absolute temperature scale in physics where it is not possible to go beyond 0 degrees Kelvin. Therefore, the lowest point that any temperature can reach is 0 K or −460 °F (−273.15 °C); at least that’s what scientists thought until till now. When they cooled an atomic gas to extreme lows, known as ‘ultracooling’, physicists at the Ludwig-Maximilians University Munich and the Max Planck Institute of Quantum Optics in Germany created a gas that went beyond absolute zero. They found that the atoms in the ultracooled gas attract each other and give rise to a negative pressure. Instead of standing still when they go beyond 0 K, the gas becomes hotter.

Software a confronto per sviluppare eBook in formato epub2, epub3 reflowable e fixed layout - Digital Index Editore Dettagli Categoria: servizi maggio 2014 Digital Index nel 2011 ha pubblicato il suo primo eBook (Parigi Sotterranea) in formato epub 2 e mobi. A maggio 2012 il primo Apple iBook (Guida al Parco archeologico e Museo all'aperto della terramare di Montale) e a marzo 2013 il primo ePub3 con video, formule matematiche e quiz (TRE IN UNO - Piccola Enciclopedia della Matematica Intrigante). Da allora la sperimentazione e lo sviluppo di queste nuove tecnologie continua, in particolare per la loro applicazione nelle collana Digital Docet dedicata ai libri di testo per la Scuola e la didattica scolastica. Ora sviluppiamo per altre case editrici sia eBook 2 che opere in epub3 fixed layout (libri per bambini e ragazzi) con funzionalità interattive e multimediali. Ci sembra giusto e opportuno condividere lo stato della sperimentazione. Ogni segnalazione di nuovi prodotti e sviluppi è ovviamente ben accetta e servirà a integrare le informazioni. Formati degli eBook nelle librerie digitali

Is dark energy static or dynamic? (Phys.org)—While hypothesized dark energy can explain observations of the universe expanding at an accelerating rate, the specific properties of dark energy are still an enigma. Scientists think that dark energy could take one of two forms: a static cosmological constant that is homogenous over time and space, or a dynamical entity whose energy density changes in time and space. By examining data from a variety of experiments, scientists in a new study have developed a model that provides tantalizing hints that dark energy may be dynamic. The scientists, Gong-Bo Zhao of the University of Portsmouth in the UK and the Chinese Academy of Science in Beijing; Robert G. Crittenden of the University of Portsmouth; Levon Pogosian of Simon Fraser University in Burnaby, British Columbia, and the University of Portsmouth; and Xinmin Zhang of the Chinese Academy of Science, have published their paper on the evidence for dynamical dark energy in a recent issue of Physical Review Letters.

Souto de Moura e il disegno “Bic/Bic/Bic – Bic Cristal – Nessuno disegna tanto per disegnare. Disegnare non è un hobby, disegnare, in Architettura, significa dover risolvere un problema. Gli architetti disegnano per dovere, non per piacere; come nella Scuola di Belle Arti, dove c’era un orario, un modello, un professore, e noi alunni chiusi tra i cavalletti. Disegnare, in Architettura, è correre contro il tempo, prendere ciò che sta a portata di mano: una scatola di fiammiferi, un biglietto del tram, un pacchetto di sigarette rovesciato, i sacchetti per il mal d’aria che si trovano in aereo, oppure il nostro quaderno, che non deve avere carta di pregio. La carta, se è di buona qualità, spessa, ci intimidisce, facciamo cerimonie, ci inibisce i gesti, e non è per la grammatura della carta che passiamo ai posteri. Anche la penna deve essere banale, leggera, anonima e disponibile in ogni angolo della città.

New phase of water could dominate the interiors of Uranus and Neptune (Phys.org) —While everyone is familiar with water in the liquid, ice, and gas phases, water can also exist in many other phases over a vast range of temperature and pressure conditions. One lesser known phase of water is the superionic phase, which is considered an "ice" but exists somewhere between a solid and a liquid: while the oxygen atoms occupy fixed lattice positions as in a solid, the hydrogen atoms migrate through the lattice as in a fluid. Until now, scientists have thought that there was only one phase of superionic ice, but scientists in a new study have discovered a second phase that is more stable than the original. The new phase of superionic ice could make up a large component of the interiors of giant icy planets such as Uranus and Neptune. The scientists, Hugh F. Exotic water As the scientists explain, water has an unusually rich phase diagram, with 15 crystalline phases observed in laboratory experiments and eight additional phases predicted theoretically.

Starting With Nothing and Ending Up With Everything by Bruce Rawles Question: What's black and white and blinks in and out of existence 1044 (a lot) times per second? And is in every 1/1033 cubic centimeter of space (every teeny tiny bit)? Answer: Hey ... Everything! —W. Okay, it's time to dig down into the mental archives of your high school geometry class. If your geometry teacher was typical, the subject of the infinitesimal point was probably glossed over quickly to usher you into more "important" theorems and pragmatic applications. But let's hit the virtual PAUSE button on the subject of the point for a while, and give it the attention it deserves. The Infinitesimal Point A pure, ideal, mathematically pristine and glittering point occupies no space. Wait just a picosecond. If so, or even if you did boggle on it a while, let's explore the dimensionless point a bit further ... so you'll get my point ... about the point. Now that could come in handy. I've also found, to the delight of Ram Dass fans worldwide, that "here" appears to be quite portable.

Exclusive: Pioneering scientists turn fresh air into petrol in massive boost in fight against energy crisis - Home News - UK Air Fuel Synthesis in Stockton-on-Tees has produced five litres of petrol since August when it switched on a small refinery that manufactures gasoline from carbon dioxide and water vapour. The company hopes that within two years it will build a larger, commercial-scale plant capable of producing a ton of petrol a day. It also plans to produce green aviation fuel to make airline travel more carbon-neutral. Tim Fox, head of energy and the environment at the Institution of Mechanical Engineers in London, said: "It sounds too good to be true, but it is true. Although the process is still in the early developmental stages and needs to take electricity from the national grid to work, the company believes it will eventually be possible to use power from renewable sources such as wind farms or tidal barrages. "There's nobody else doing it in this country or indeed overseas as far as we know. "We ought to be aiming for a refinery-scale operation within the next 15 years.

Sephirot Sephirot (/sfɪˈroʊt/, /ˈsfɪroʊt/; Hebrew: סְפִירוֹת‎ Səphîrôṯ), meaning emanations, are the 10 attributes/emanations in Kabbalah, through which Ein Sof (The Infinite) reveals himself and continuously creates both the physical realm and the chain of higher metaphysical realms (Seder hishtalshelus). The term is alternatively transliterated into English as Sefirot/Sefiroth, singular Sephirah/Sefirah etc. Alternative configurations of the sephirot are given by different schools in the historical development of Kabbalah, with each articulating different spiritual aspects. The tradition of enumerating 10 is stated in the Sefer Yetzirah, "Ten sephirot of nothingness, ten and not nine, ten and not eleven". In Hasidic philosophy, which has sought to internalise the experience of Jewish mysticism into daily inspiration (dveikus), this inner life of the sephirot is explored, and the role they play in man's service of God in this world. Ten Sephirot[edit] Listings[edit] Description[by whom?] [edit]

Taming mavericks: Researchers use synthetic magnetism to control light (Phys.org)—Stanford researchers in physics and engineering have demonstrated a device that produces a synthetic magnetism to exert virtual force on photons similar to the effect of magnets on electrons. The advance could yield a new class of nanoscale applications that use light instead of electricity. Magnetically speaking, photons are the mavericks of the engineering world. Lacking electrical charge, they are free to run even in the most intense magnetic fields. The process breaks a key law of physics known as the time-reversal symmetry of light and could yield an entirely new class of devices that use light instead of electricity for applications ranging from accelerators and microscopes to speedier on-chip communications. "This is a fundamentally new way to manipulate light flow. The ability to use magnetic fields to redirect electrons is a founding principle of electronics, but a corollary for photons had not previously existed.

Stop Motion: Tutorials 09 feb 2014 Esistono moltissimi video sul web che possono mostrarci in maniera molto 23 nov 2013 Will Harding, model marker della Aardman Studios, durante l’ExpoPixel del FFF di quest’anno ha 24 mag 2013 Con la clay painting si passa dal piacere tattile del mondo 07 ott 2012 Continuiamo ad esaminare le possibilità che una stop-motion offre attraverso l’esempio 23 giu 2012 Si effettua componendo tra loro dei ritagli di carta, stoffa o 19 giu 2012 In una claymation i personaggi sono realizzati in plastilina, a volte 16 giu 2012 All’interno del modello in plastilina è necessaria una struttura rigida che 14 giu 2012 Come ci suggerisce già il suo nome questa tipologia di stop-motion 12 giu 2012 Realizzare un’animazione è un modo articolato e stimolante per dare vita 10 giu 2012 Tecnica tipicamente usata per animare pupazzi, modellini, marionette o fantocci, provvisti 09 giu 2012 Pixilation La Pixilation è la tecnica che Meliès utilizzò per inaugurare i primi effetti speciali 25 mag 2012 26 apr 2012 30 mar 2012

A new probe for spintronics The spin Hall effect (SHE) enables us to create spin current in non-magnetic materials without using ferromagnetic materials. It is a crucial element in the central idea behind spintronics, that of manipulating currents of spin instead of currents of charge. Since the first experimental report on the SHE in semiconductors in 2004, the phenomenon and its mechanism have been intensively studied to find out more efficient and economical methods of generation of the spin current, both in semiconductors and metals. The inverse process of SHE (ISHE) is similarly recognized as a key step to be mastered in order to convert the spin current back into a charge current. So while both the SHE and its inverse are important for the potential applications, there are few examples of their use as an electrical detector of more fundamental properties of condensed matter. Explore further: Information storage for the next generation of plastic computers

Scrivere Architettura. Instabilità del “genere” e trivellazione della “forma” | alienlog Antonello Da Messina. San Gerolamo nello studio. 1474 – 1475 Intervento proposto nel corso del convegno “Presente Teorico condizioni e possibilità per una teoria dell’architettura” Una premessaIo penso che l’architetto debba includere nel proprio patrimonio di conoscenze, oltre agli aspetti tecnico-deontologici e scientifici, un vettore “critico” in grado di porlo in modo non incerto al centro delle questioni fondamentali della disciplina, alfine di acquisire una complessiva consapevolezza dell’importanza politica e culturale che ricopre nella società. Io penso infatti che l’abiura, il sofferto disincanto, lo scetticismo rassegnato che ha contraddistinto il modo di guardare all’architettura e all’identità professionale ed intellettuale dell’architetto negli ultimi anni, derivi dall’aver estromesso volontariamente l’istanza culturale, teorico-critica, dalla nostra ottica complessiva. Rachel Whiteread. Il progetto del “testo” o il testo come “progetto” Claude Nicolas Ledoux. Aldo Rossi.

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