2022-03-31 - Nº 361
Esta é a Newsletter Nº 361 que se apresenta com o mesmo formato que as anteriores. Se gostar da Newsletter partilhe-a!
Todas as Newsletters encontram-se indexadas no link.
Esta Newsletter tem os seguintes tópicos:
Faz hoje anos que nascia, em 1596, o filósofo e matemático francês René Descartes. Ele é conhecido como "o pai da filosofia moderna". A sua obra, La géométrie, inclui a sua aplicação da álgebra à geometria, da qual temos agora a geometria cartesiana. Durante 1620-28, Descartes viajou pela Europa, estabelecendo-se depois na Holanda. Pouco depois, começou a trabalhar no seu primeiro grande tratado sobre física, Le Monde, ou Traité de la Lumière. Este trabalho estava quase concluído quando lhe chegou a notícia de que Galileu estava condenado a prisão domiciliária. Ele decidiu não publicar essa obra durante a sua vida. Mais tarde, recorreu à filosofia, uma das primeiras a opor-se ao aristotelismo escolástico, começou por duvidar metodicamente dos conhecimentos baseados na autoridade, nos sentidos e na razão. A sua citação mais famosa é "Penso, logo existo".
Faz também hoje anos que nascia, em 1831, o químico escocês Archibald Scott Couper. Ele, independentemente de August Kekulé, propôs a tetravalência do carbono e a capacidade dos átomos de carbono de se ligarem uns aos outros para formar longas cadeias, conceitos fundamentais para compreender as moléculas encontradas nos organismos vivos. Também criou a utilização de uma linha entre símbolos de elementos para indicar uma ligação química. Escreveu estas ideias marcantes num artigo a ser submetido à Academia Francesa de Ciências através do seu superior, Adolphe Wurtz. Infelizmente para Couper, esse trabalho não foi enviado do laboratório em tempo útil, e entretanto outro químico, August Kekulé tinha publicado a mesma ideia, embora independente, de tetravalência, privando Couper da sua devida fama.
Faz igualmente hoje anos que nascia, em 1854, o inventor escocês Dugald Clerk. Ele criou o motor de motociclos de dois tempos, amplamente utilizado em motociclos ligeiros e outras pequenas máquinas. Em 1881 patenteou um motor que construiu em 1876 para funcionar com vapor de hidrocarboneto que utilizava uma explosão a cada dois tempos do pistão em vez de uma explosão a cada dois tempos do ciclo Otto mais comum utilizado pela maioria dos motores de automóveis. Numa outra direcção de investigação importante, estudou as propriedades do combustível gasoso e as suas aplicações de aquecimento e iluminação. O Almirantado britânico nomeou-o director da investigação de engenharia em 1916, seguido do seu cavaleiro em 1917. O seu trabalho aparece nos dois volumes de The Gas, Petrol, e Oil Engine.
Faz também hoje anos que nascia, em 1890, o físico australiano-inglês William Lawrence Bragg. Ele, aos 25 anos de idade, partilhou o Prémio Nobel da Física em 1915 (com o seu pai, Sir William Bragg). Lawrence Bragg formulou a lei Bragg da difracção de raios X, que é fundamental para a determinação da estrutura cristalina: nλ = 2dsinθ que relaciona o comprimento de onda dos raios X, λ, o ângulo de incidência num cristal, θ, e o espaçamento dos planos de cristal, d, para a difracção de raios X, onde n é um número inteiro (1, 2, 3, etc.). Em conjunto, os Braggs trabalharam as estruturas cristalinas de uma série de substâncias. No início deste trabalho, mostraram que o cloreto de sódio não tem moléculas individuais no sólido, mas é um conjunto de iões de sódio e cloreto.
Faz igualmente hoje anos que nascia, em 1906, o físico japonês Shin'ichirō Tomonaga. Ele partilhou o Prémio Nobel da Física em 1965 (com Richard P. Feynman e Julian S. Schwinger dos EUA) por desenvolver independentemente princípios básicos de electrodinâmica quântica. Foi um dos primeiros a aplicar a teoria quântica às partículas subatómicas com energias muito elevadas. Tomonaga começou com uma análise do acoplamento intermédio - a ideia de que as interacções entre duas partículas ocorrem através da troca de uma terceira (partícula virtual), como um navio que afecta o outro ao disparar uma bala de canhão. Ele utilizou este conceito para desenvolver uma teoria quântica de campo (1941-43) que era consistente com a teoria da relatividade especial. A Segunda Guerra Mundial atrasou as notícias do seu trabalho. Entretanto, Feynman e Schwinger publicaram as suas próprias soluções independentes.
Por fim, faz hoje anos que nascia, em 1934, o físico italiano Carlo Rubbia. Ele foi responsável pela descoberta da partícula W subatómica maciça e de curta duração e da partícula Z. Por volta de 1960, juntou-se ao recém fundado CERN, onde investigou a estrutura das interacções fracas. Em 1976, sugeriu a adaptação do Super Proton Synchrotron (SPS) do CERN para colidir protões e antiprotões no mesmo anel e a primeira fábrica mundial de antiprotões foi construída, e começou a funcionar em 1981. Em Janeiro de 1983, veio o anúncio, primeiro a partir do detector UA1, de que as partículas W tinham sido criadas. Alguns meses mais tarde, as partículas Z ainda mais esquivas foram também observadas. Estas partículas são os portadores da chamada força fraca envolvida na decadência radioactiva dos núcleos atómicos.
Em 1889, a Torre Eiffel, Paris, França, foi inaugurada, tornando-se a torre mais alta do mundo da sua época. Com uma altura de 300 m, continuou a ser a estrutura mais alta do mundo até ser ultrapassada pelo Empire State Building, 40 anos mais tarde. O designer Gustave Eiffel, 56 anos, celebrou desfraldando uma bandeira francesa no topo da torre. O imenso desenho das treliças de ferro foi escolhido por unanimidade entre 700 propostas apresentadas num concurso. A construção decorreu entre 26 de Janeiro de 1887 e 31 de Março de 1889, utilizando 300 trabalhadores siderúrgicos. Foi erguida para a Exposição de Paris de 1889, que contou com 1.968.287 visitantes. Os elevadores eram alimentados por maquinaria nos porões dos pilares oriental e ocidental.
Na Newsletter desta semana apresentamos diversas noticias, artigos científicos, projetos de maker e alguns vídeos interessantes. É apresentada a revista MagPI nº116 de Abril.
João Alves ([email protected])
O conteúdo da Newsletter encontra-se sob a licença Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Novidades da Semana
"Intel today announced full details and availability for the new 12th Gen Intel® Core™ i9-12900KS, the world’s fastest desktop processor1. It delivers up to 5.5 GHz max turbo frequency — in spec with Intel® Thermal Velocity Boost and features Intel® Adaptive Boost Technology (Intel® ABT) to provide the ultimate gaming experience. The unlocked i9-12900KS processor is the ultimate processor for enthusiasts and gamers who want the fastest processor available. With 16 cores (eight Performance-cores and eight Efficient-cores) and 24 threads, and up to 5.5 GHz max turbo frequency, 150W processor base power and 30MB Intel® Smart Cache for even more gaming power and performance. What It Offers: Key features and capabilities of the i9-12900KS include: - Up to 5.5 GHz max turbo frequency with Intel Thermal Velocity Boost. - Intel Adaptive Boost Technology for improved gaming performance by opportunistically allowing higher multi-core turbo frequencies." [...]
"Announcing a new secure storage subsystem and key provisioning for the Wireless Power Consortium (WPC) Qi 1.3 Wireless Charging standard. In order to ensure high quality wireless charging power transmitters, the Wireless Power Consortium (WPC) has released the Qi® 1.3 specification with the extended power profile. This new specification created demand for high security silicon authentication devices for full-service support. In response, Microchip Technology Inc. (Nasdaq: MCHP) is announcing the new industrial grade TrustFLEX ECC608 and the automotive grade Trust Anchor TA100 combined with Microchip secure key provisioning services for Qi 1.3 power transmitters. This new offering is an all-in-one secure storage subsystem that includes key provisioning for consumer and automotive systems. The Qi 1.3 specification now mandates the addition of a secure storage subsystem with secure key provisioning including X.509 certificates to cryptographically verify the source and quality of the certified power transmitter." [...]
Toshiba Releases 150V N-channel Power MOSFET that Uses Latest Generation Process to Improve Power Supply Efficiency
"Toshiba Electronic Devices & Storage Corporation ("Toshiba") has launched a 150V N-channel power MOSFET “TPH9R00CQH” that uses the latest generation process, “U-MOSX-H,” and that is suitable for use in switching power supplies for industrial equipment—including those deployed in data centers and communications base stations. Shipments start today. TPH9R00CQH has a drain-source On-resistance about 42% lower than TPH1500CNH, a 150V product that uses the current generation process, U-MOSⅧ-H. Optimization of the new MOSFET’s structure has improved the trade-off between the drain-source On-resistance and two charge characteristics, realizing excellent low-loss characteristics. In addition, spike voltage between the drain and source at switching operation is reduced, helping to lower electromagnetic interference (EMI) in switching power supplies. Two types of surface mount packages are available: SOP Advance and the more popular SOP Advance(N). Toshiba also offers tools that support circuit design for switching power supplies." [...]
"The first Intel Arc A-Series graphics processing units will power laptops, with more products coming this year for desktops and workstations. For decades, Intel has been a champion for PC platform innovation. We have delivered generations of CPUs that provide the computing horsepower for billions of people. We advanced connectivity through features like USB, Thunderbolt™ and Wi-Fi. And in partnership with the PC ecosystem, we developed the ground-breaking PCI architecture and the Intel® Evo™ platform, pushing the boundary for what mobile products can do. Intel is uniquely positioned to deliver PC platform innovations that meet the ever-increasing computing demands of professionals, consumers, gamers and creators around the world." [...]
"FedEx and Elroy Air work to launch test flights aimed at middle-mile delivery in 2023. FedEx Express, a subsidiary of FedEx Corp. (NYSE: FDX) and the world’s largest express transportation company, is teaming up with California Bay Area-based Elroy Air, the company building the first end-to-end autonomous vertical take-off and landing (VTOL) aerial cargo system. As a first of its kind agreement in the U.S., FedEx Express will develop plans to test Elroy Air’s Chaparral autonomous air cargo system within the company’s middle-mile logistics operations, moving shipments between sortation locations. This is the latest initiative from FedEx in its effort to explore and adopt emerging technologies across its networks. The exponential growth of e-commerce has accelerated the demand for reliable, efficient transportation and logistics solutions throughout all stages of the supply chain. FedEx believes that continued innovation and automation will improve safety, efficiency, and productivity for the company’s 600,000 team members as they continue to move the world forward." [...]
"A New Shepard vehicle lifted off from Blue Origin's Launch Site One in West Texas on Thursday (March 31) at 9:58 a.m. EDT (1358 GMT), carrying a crew of six people to suborbital space. Just about 10 minutes later, those folks came back down to Earth, their capsule raising a plume of dust as it touched down in the desert. "It's the most beautiful thing I've ever seen," passenger Sharon Hagle said on exiting the capsule. Their mission was called NS-20, because it was the 20th spaceflight of a New Shepard vehicle. But it was just the fourth crewed Blue Origin flight, and the first that didn't feature a celebrity passenger. The first crewed New Shepard mission sent Blue Origin founder and CEO Jeff Bezos, aviation pioneer Wally Funk and two other people to the final frontier on July 20, 2021." [...]
Ciência e Tecnologia
"A team co-led team by the University of Surrey has successfully increased the levels of energy absorbed by wafer-thin photovoltaic panels by 25%. Their solar panels, just one micrometre thick (1μm), convert light into electricity more efficiently than others as thin and pave the way to make it easier to general more clean, green energy. In a paper published in the American Chemical Society’s Photonics journal, the team detail how they used characteristics of sunlight to design a disordered honeycomb layer which lies on top of a wafer of silicon. Their approach is echoed in nature in the design of butterfly wings and bird eyes. The innovative honeycomb design enables light absorption from any angle and traps light inside the solar cell, enabling more energy to be generated. The team of researchers from the University of Surrey and Imperial College London worked with experimental collaborators at AMOLF in Amsterdam to design, model and create the new ultra-thin photovoltaic." [...]
"A new technology could make rocket launches more successful When it comes to materials, engineers are always looking for something better. There is a constant need for stronger, lighter and easier-to-produce materials that can withstand harsh environments. This is particularly true for aerospace applications. The smallest defect in a material used in rockets can have catastrophic, costly consequences. Safely launching and landing spacecraft, especially reusable spacecraft, requires thorough inspections to identify potential manufacturing flaws. There are, of course, nondestructive evaluation techniques that aim to find defects in materials before launch, but current techniques are limited in what they can detect." [...]
"What kind of high-tech materials for the electronics, power, and textile industries are being made in Russia? Which projects are developed in St. Petersburg and what is their potential? These and other questions were discussed at a recent TASS news agency’s press conference that featured heads of strategic projects and experts from St. Petersburg universities. Among the press conference’s participants were: head of ITMO’s Engineering Center “M2M Telecontrol and Instrumentation” Viktoria Zheltova; associate professor at the Institute of Physics, Nanotechnologies and Telecommunications of Peter the Great St. Petersburg Polytechnic University Roman Burkovsky; head of the Department of Micro and Nanoelectronics at LETI University Viktor Luchinin; professor at the St. Petersburg State University of Industrial Technologies and Design head of the Smart Textile strategic project Elena Sashina; and associate professor at the Engineering Materials Science Department of the St. Petersburg State University of Industrial Technologies and Design and head of the FashionTech Center for Technology and Competence Transfer within the Priority 2030 initiative Olga Moskalyuk. Flexible electronics The past decade saw active development in the field of flexible electronics. Major companies are already working on bendable smartphones or TVs that can be rolled up like paper without losing their properties." [...]
"An interface-templated method enhances the crystallinity of large single-layer graphene sheets on insulating supports. An approach that produces single-crystal graphene sheets on large-scale electrically insulating supports could help with the development of next-generation nanomaterial-based devices, such as very light and thin touchscreens, wearable electronics and solar cells. Most graphene-based electronic devices require insulating supports. Yet, high-quality graphene films destined for industrial use typically are grown on a metal substrate, such as copper foil, before being transferred to an insulating support for device fabrication. This transfer step can introduce impurities that affect how well the device performs. Efforts to grow graphene on insulating supports have not been able to produce the required high-quality single crystals." [...]
"MIT, RPI, and SUNY convene a national conversation on semiconductor tech translation and hard-tech startups. A growing gap in the transition of inventions from research labs to market is slowing the development and scale-up of new hardware technologies in the United States. This is particularly evident in complex microelectronics advancements, in which U.S. leadership has lagged. A workshop on semiconductor technology translation and hard-tech startups recently gathered stakeholders from across the country to analyze this challenge and propose solutions. Presented jointly last month by MIT, the State University of New York (SUNY), and Rensselaer Polytechnic Institute (RPI), the virtual event brought together academic researchers, members of industry, venture capital firms, state and federal agencies, nonprofit organizations, venture accelerators, and startups for a wide-ranging conversation on how to recapture U.S. leadership. In his opening remarks, MIT Provost Martin Schmidt challenged the speakers and attendees to seize the moment." [...]
"The research project INSPIRE develops a unique printing technique for large-scale production of optical chips consisting of layers of different materials. Faster, more energy-efficient ICT, or sensors to detect anything between beginning fruit rot and microscopic cracks in glass fibers: photonic technology holds great promises for the future. To deliver on those promises, a European consortium led by TU/e researchers takes the next step. The INSPIRE project uses a novel printing method to enable mass fabrication of hybrid photonic chips. These combine multiple technologies to create new possibilities for applications. Over the past decades, a myriad of technologies has been developed to produce minuscule devices that generate, detect, process and transport light." [...]
"A University of Rochester project uses flat panel technology to build a more cost-effective device that can also function as a touch interface. Over the past decade, smart devices have become essential components of daily life: doorbells, watches, keychains—even thermostats. But many smart devices, such as televisions, laptops, smartphones, and car “infotainment” dashboard consoles, rely on visual presentation of information. That can be a problem when a person’s visual attention is focused on something other than the device. One way to address this problem is to let people use sound or touch for interactions. Of course, adding separate microphones, loudspeakers, and vibration mechanisms using conventional means can impose extra costs and reduce the device’s durability and aesthetics." [...]
"Rice process customizes one-, two- or three-element doping for applications. Flashing graphene into existence from waste was merely a good start. Now Rice University researchers are customizing it. The Rice lab of chemist James Tour has modified its flash Joule heating process to produce doped graphene that tailors the atom-thick material’s structures and electronic states to make them more suitable for optical and electronic nanodevices. The doping process adds other elements to graphene’s 2D carbon matrix. The process reported in the American Chemical Society journal ACS Nano shows how graphene can be doped with a single element or with pairs or trios of elements." [...]
"A new technique could enable a robot to manipulate squishy objects like pizza dough or soft materials like clothing. Imagine a pizza maker working with a ball of dough. She might use a spatula to lift the dough onto a cutting board then use a rolling pin to flatten it into a circle. Easy, right? Not if this pizza maker is a robot. For a robot, working with a deformable object like dough is tricky because the shape of dough can change in many ways, which are difficult to represent with an equation." [...]
"Nuclear medicine uses technetium-99m among other things for tumor diagnostics. With over 30 million applications worldwide each year, it is the most widely used radioisotope. The precursor material, molybdenum-99, is mainly produced in research reactors. A study at the Heinz Maier-Leibnitz Research Neutron Source (FRM II) at the Technical University of Munich (TUM) now shows options to significantly reduce the radioactive waste produced during processing to a medical product. Over 85 percent of all nuclear medicine diagnostic examinations use technetium-99m (Tc-99m). In Germany alone, more than 3 million doses are deployed every year." [...]
"Lego blocks, beloved by both children and adults, can be assembled into set models like space shuttles or cool buildings, but also can be used to build any new structures. Like these blocks, a new technology has been proposed to assemble atomic-sized blocks into new materials. A POSTECH research team led by Professor Cheol-Joo Kim and Ph.D. candidates Seong-Jun Yang and Ju-Hyun Jung (Department of Chemical Engineering) in collaboration with Dr. Chang Cuk Hwang and Dr. Eunsook Lee (Pohang Accelerator Laboratory) and Professor Pinshane Y. Huang and Ph.D. candidate Edmund Han (University of Illinois Urbana-Champagne) has developed a technology for assembling wafer*1-scale films at the atomic level. Recently published as the front cover paper of Nano Letters, the findings are a result of precisely designing the structure of materials at the atomic level. Crystal*2 films composed of atoms offer varying physical properties based on the modulation of their thickness or atomic structures. Varying the stacking configuration of these thin films – layer-by-layer or twisted – produces different physical properties." [...]
"A POSTECH research team led by Professor Gil-Ho Lee and Gil Young Cho (Department of Physics) has developed a platform that can control the properties of solid materials with light and measure them. Recognized for developing a platform to control and measure the properties of materials in various ways with light, the findings from the study were published in the top international academic journal Nature on March 15, 2022 (GMT). The electrical properties of a material are determined by the movement of electrons in the material. For example, a material is defined as a metal if electrons can move freely, otherwise it is an insulator. In order to change the electrical properties of these solids, applying heat or pressure or adding impurities have been generally used. This is because the change in the position of the atoms in the solid changes the movement of electrons accordingly." [...]
"A cutting-edge nuclear thermal propulsion (NTP) rocket engine using what’s called centrifugal liquid fuel bubble-through could one day be a ticket for NASA to go directly into deep space. Under an NTP research contract for the Space Nuclear Propulsion Project Office at NASA’s Marshall Space Flight Center (MSFC), The University of Alabama in Huntsville (UAH), a part of the University of Alabama System, is leading a collaboration of universities across the nation including the University of Rhode Island (URI), Drexel University, the Massachusetts Institute of Technology (MIT), Pennsylvania State University and the University of Michigan (U-M) to research the concept. NASA has made substantial advances toward a solid fuel NTP design. The bubble-through concept under study by the university collaborators is one of three proposed hydrogen-based designs for a next generation liquid fuel NTP rocket. Either in person or virtually, all of NASA’s NTP academic partners will gather on March 11 at a workshop hosted by UAH for NASA to discuss their progress and issues. The bubble-through centrifugal NTP concept heats hydrogen gas propellant to super-hot temperatures, but there is no combustion." [...]
"Researchers at Nara Institute of Science and Technology develop a new mathematical method to calibrate scans of stained-glass windows to account for changes in natural light, which may help assist in the accurate preservation of famous artworks Scientists from Nara Institute of Science and Technology created a new approach to compensate for variations in illumination while scanning cathedral stained-glass windows. This work may be applied to other objects of cultural significance to help capture their colors in the most lifelike way. It's hard to think of a more inspirational experience than watching the sun slowly set through historic stained-glass windows, such as those found in the cathedrals in Europe. While the changing light levels over time may be breathtaking, it also makes high-resolution scans of the windows more challenging. That is, if the scanning process requires minutes or even hours to complete, variations in the natural illumination can lead to inconsistent results. Now, a team of researchers led by Nara Institute of Science and Technology has developed a new calibration method to help compensate for changes in the sun's illumination over the course of the scan." [...]
"Physicists know about the huge chasm between quantum physics and the theory of gravity. However, in recent decades, theoretical physics has provided some plausible conjecture to bridge this gap and to describe the behaviour of complex quantum many-body systems, for example black holes and wormholes in the universe. Now, a theory group at Freie Universität Berlin and HZB, together with Harvard University, USA, has proven a mathematical conjecture about the behaviour of complexity in such systems, increasing the viability of this bridge. The work is published in Nature Physics. "We have found a surprisingly simple solution to an important problem in physics," says Prof. Jens Eisert, a theoretical physicist at Freie Universität Berlin and HZB. "Our results provide a solid basis for understanding the physical properties of chaotic quantum systems, from black holes to complex many-body systems," Eisert adds." [...]
"Semiconductor electronics is getting faster and faster - but at some point, physics no longer permits any increase. The shortest possible time scale of optoelectronic phenomena has now been investigated. How fast can electronics be? When computer chips work with ever shorter signals and time intervals, at some point they come up against physical limits. The quantum-mechanical processes that enable the generation of electric current in a semiconductor material take a certain amount of time. This puts a limit to the speed of signal generation and signal transmission." [...]
"Quantum bits (qubits) are the smallest units of information in a quantum computer. Currently, one of the biggest challenges in developing this kind of powerful computer is scalability. A research group at the University of Basel, working with the IBM Research Laboratory in Rüschlikon, has made a breakthrough in this area. Quantum computers promise unprecedented computing power, but to date prototypes have been based on just a handful of computing units. Exploiting the potential of this new generation of computers requires combining large quantities of qubits. It is a scalability problem which once affected classic computers, as well; in that case it was solved with transistors integrated into silicon chips." [...]
"Collisions of light with deuterons offer insight into gluelike particles that bind the building blocks of matter—and what it takes to break protons and neutrons apart. Scientists have found a new way to “see” inside the simplest atomic nuclei to better understand the “glue” that holds the building blocks of matter together. The results, just published in Physical Review Letters, come from collisions of photons (particles of light) with deuterons, the simplest atomic nuclei (made of just one proton bound to one neutron). The collisions took place at the Relativistic Heavy Ion Collider (RHIC), a U.S. Department of Energy (DOE) Office of Science user facility for nuclear physics research at DOE’s Brookhaven National Laboratory. Scientists from around the world analyze data from RHIC’s subatomic smashups to gain insight into the particles and forces that build up the visible matter of our world. In these particular collisions, the photons acted somewhat like an x-ray beam to provide the first glimpse of how particles called gluons are arranged within the deuteron." [...]
"Researchers from ICFO in Barcelona, Columbia University, NTU in Singapore and NIMS in Japan, report in Science on experimentally achieving for the first time the bending of electrons in bilayer graphene with the use of light. The way electrons flow in materials determine its electronic properties. For example, when a voltage is sustained across a conducting material, electrons start flowing, generating an electrical current. These electrons are often thought to flow in straight paths, moving along the electric field, much like a ball rolling down a hill. Yet these are not the only trajectories electrons can take: when a magnetic field is applied, the electrons no longer travel in straight paths along the electric field, but in fact, they bend. The bent electronic flows lead to transverse signals called “Hall” responses." [...]
"Newly discovered Fermi arcs that can be controlled through magnetism could be the future of electronics based on electron spins. These new Fermi arcs were discovered by a team of researchers from Ames Laboratory and Iowa State University, as well as collaborators from the United States, Germany, and the United Kingdom. During their investigation of the rare-earth monopnictide NdBi (neodymium-bismuth), the research team discovered a new type of Fermi arc that appeared at low temperatures when the material became antiferromagnetic, i.e., neighboring spins point in opposite directions. Fermi surfaces in metals are a boundary between energy states that are occupied and unoccupied by electrons. Fermi surfaces are normally closed contours forming shapes such as spheres, ovoids, etc. Electrons at the Fermi surface control many properties of materials such as electrical and thermal conductivity, optical properties, etc." [...]
"Study by the University of Bonn could pave the way to new types of highly sensitive sensors Researchers at the University of Bonn have created a gas of light particles that can be extremely compressed. Their results confirm the predictions of central theories of quantum physics. The findings could also point the way to new types of sensors that can measure minute forces. The study is published in the journal Science. If you plug the outlet of an air pump with your finger, you can still push its piston down. The reason: Gases are fairly easy to compress - unlike liquids, for example." [...]
"Metallic materials used in engineering must be strong and ductile – capable of carrying high mechanical loads while able to withstand deformation without breaking. Whether a material is weak or strong, ductile or brittle, however, is not determined simply by the crystal grains that make up the material, but rather by what happens in the space between them known as the grain boundary. Despite decades of investigation, atomic-level deformation processes at the grain boundary remain elusive, along with the secret to making new and better materials. Using advanced microscopy coupled with novel computer simulations that track atomic movement, researchers at the Georgia Institute of Technology conducted real-time atomic-level observations of grain boundary deformation in poly-grained metallic materials called polycrystalline materials. The team observed previously unrecognized processes that affect material properties, such as atoms that hop from one plane to another across a grain boundary. Their work, published in Science this March, pushes the limits of atomic-level probing, and enables a deeper understanding of how polycrystalline materials deform." [...]
A documentação é parte essencial do processo de aprendizagem e a Internet além de artigos interessantes de explorar também tem alguma documentação em formato PDF interessante de ler. Todos os links aqui apresentados são para conteúdo disponibilizado livremente pelo editor do livro.
"Inside The MagPi magazine #116 - Hidden Hacks for Raspberry Pi. We unearth the Rasperry Pi secrets every owner should know - Capture the night sky with astrophotography. Take incredible photos of starry skies with Raspberry Pi - The top 10 Raspberry Pi robots. An incredible collection of mechanical friends built by The MagPi readers - Raspberry Pi Spectrum inside a cassette tape. Celebrate 40 years of Sinclair’s classic computer by putting Raspberry Pi inside a Boots’ C90 cassette tape - Learn ARM assembly language. Speak the language of computing by learning assembly with Raspberry Pi - Set up a digital audio workstation." [...]
Diversos Projetos interessantes.
"Welcome to this Instructable, I've wanted to build one of these Labyrinth Games for some time now but rather than use the conventional method with the hand turn knobs, I wanted to use 2 of the small 28BYJ-48 stepper motors controlled by a Joystick to move both Axis. Disclaimer: This game is not my idea, there are various Labyrinth games out there, whether there are games utilising stepper motors and a Joystick then I don't know, this version is just my take on the game. The stepper motors should make for a smoother and more precise axis movement in theory which is needed to navigate the steel ball through the course, the whole idea of a game of skill is that it can be achieved, a lot I have seen are nearly impossible to complete, so some thought must be given to the layout and the route the ball must take to achieve this goal. I will be using some left over spruce boards from a garden bench build and an off cut of 10mm Mdf for the playing area, the base will be 3mm ply For everything to work correctly the woodworking may be beyond my skills, I'm not that precise but with this type of build, everything has to be precise especially with Axis movement. On the Electronics side I am using an Arduino Nano with servo shield, with digital pins used for the stepper motors and Analog pins for the Joystick. The stepper motors are driven by the ULN2003 driver boards." [...]
"MyBroadband successfully played Doom ported to a Raspberry Pi Pico using guidelines provided by Graham Sanderson, also known as Kilograham. The Raspberry Pi Pico is a microcontroller with a dual-core ARM Cortex-M0+ processor, 264KB of RAM, and 2MB of flash storage. The device costs R69.90 in South Africa. With only 2MB of storage, most people assume using the Raspberry Pi Pico for gaming is impossible. They are wrong. Graham managed to recompress the shareware version of Doom and everything needed to make it run on the Pico into the 2MB of storage." [...]
"1 Watt FM Transmitter amplifier with a reasonably balanced design specified to boost a RF frequency in the 88 – 108 MHz spectrum. It may be considered a fairly sensitive configuration when used with quality RF power amplifier transistors, trimmers and inductors. It involves a power amplification factor of 9 to 12 dB (9 to 15 times). At an input power of 0.1W the output may be well over 1W. It's advisable to choose T1 transistor on the basis of the input voltage. For 12V voltage it is recommended to use transistors such as 2N4427, KT920A, KT934A, KT904, BLX65, 2SC1970, BLY87." [...]
"Via MKR GSM 1400, collate water quality data from resources over GPRS to train a Neuton model, run the model, and transmit results via SMS. In this project, I focused on developing an AI-driven budget-friendly device to collect water quality data from various water resources in the field and forecast water pollution levels based on oxidation-reduction potential (ORP), pH, total dissolved solids (TDS), and turbidity measurements. Why is water pollution a global issue? Since we incessantly pollute our limited water resources, which are already drowning in chemicals, waste, plastic, and other contaminants, it is crucial to eschew water pollution before it is too late for relieving the plight of people lacking safe drinking water. Although there are international efforts and campaigns to plummet water contaminants, it is yet a pressing issue to track water pollution levels locally to get prescient warnings regarding possible health and environmental risks. In addition to threatening terrestrial animals, plants, and marine life, water pollution is jeopardizing our health." [...]
"Spin the knob to browse 5,000+ genres of music along with your own playlists. Knobby is a distinctive remote control for Spotify and more. Explore a universe of music with just a knob Knobby is a remote made for discovering new music and rediscovering your own collection. It’s the perfect companion to a smart speaker, allowing you to browse playlists, see what’s playing, and control playback without interrupting anything. Preloaded with thousands of genre and country playlists from Every Noise at Once, it encourages you to explore unfamiliar music and puts all of Spotify on shuffle. Untether music from your phone Bring music discovery into your living room with a device that’s meant to be shared and free from distracting apps or notifications." [...]
"This is my next build using LED matrix's. You may have seen my last one - 81 LED Chaser, well this project uses 100 LED's and is an oscilloscope! Admittedly, the resolution isn't great for checking measurements (it is only 100 pixels!). However, it is fantastic at visualizing audio waveforms via a mic. There are 4 IC's that make up the project. First there are the 4017 decade counter and a LM3914 LED driver which control the LED's." [...]
"Maker Your Own DIY Professional Bench Power Supply Using A Old Computer PSU Every workbench should have at least one power supply. When you’re experimenting with electronics and microcontrollers a good power supply can be an essential piece of equipment. While you can certainly make do with USB power bricks and “battery eliminators” nothing beats having a dedicated power supply with plenty of voltage selection and current capability. An ideal workbench power supply should have both 5-volt and 12-volt outputs, with 3.3-volts being a nice option as well. It should be capable of providing several amperes of current for each voltage. You can buy bench power supplies of course, but they are not inexpensive." [...]
"Measuring a body temperature using contactless sensor When debugging an electronics circuit or testing a new hardware design, often times I tend to check if the components on the board are getting hot abnormally by touching them. And if something is messed up (which usually is in the first try) these components could get as hot as 80°C or more burning not only the component but also my finger along with it. After burning my fingers for more times than I could remember I decided to build my own Temperature Gun using Arduino and an Infrared Temperature Sensor. This Thermal gun will be built using a non-contact temperature sensor called MLX90614; hence it can not only be used to measure component temperatures but can also be used for measuring body temperature, surface temperature, Heat ventilation and much more. Of course, these thermal guns are readily available in the market from renowned manufacturers like Fluke, Flir etc. But they are not light on your pockets and on top of that what is more fun than building your own gadgets." [...]
"A 6-keys DIY Macropad using XIAO RP2040 I always wanted to make a DIY Macropad myself. In this project, we will go through the process of making a 6-keys Macropad using a Seeed Studio XIAO RP2040 which is a tiny development board. This is my first PCB design project using KiCad EDA. Hardware components First, we have to decide about what are we going to use in this project. In my case, I am going to use the following components. " [...]
"Made a PCB badge of our beloved hero Goku, LEDs sequence will look like Kamehameha in this badge. The idea here was to make a simple PCB badge that includes Goku, I placed a few LEDs on this board in such a way that when it is being driven by an Attiny13A, it glows in a chasing pattern and it creates an illusion of Goku firing his famous Kamehameha wave. MATERIAL REQUIRED Here's a shortlist of componenets I used in this built- - Attiny13A - Custom PCB - 8205S Mosfets - 0603 RED LEDs (Blue would look better) - Coin Cell Holder (SMD) - 10K Resistance - 1K Resistance - USB Type C port" [...]
"A heater similar to commercial one and made for low end tasks. Like PVC or plastic cutting or to heat small knifes and cutters. Hello guys, as you know I don’t have any 3d printer till now. So, I made my projects and 3d styled cases using PVC pipes. The cutting and molding of PVC can be done using heated knife or hot cutter. Heating a knife on gas stove or by electric nichrome wire is not recommended in this case." [...]
"Pulse Electromagnetic Field Therapy uses electromagnetic fields in an attempt to heal non-union fractures and depression. Pulsed electromagnetic field therapy (PEMF therapy), also known as low field magnetic stimulation (LFMS) uses electromagnetic fields in an attempt to heal non-union fractures and depression. In addition, PEMF therapy improves sleep, mental focus, and the body’s overall performance by helping the energy output and regeneration of the body’s cells. Commercial such devices are sold at a price of several hundred to thousands of dollars, so my goal is to make the simple to build and functional device available to more people who can not afford it. This time I will show you a simplest way to make a PEMF device, which gives a magnetic flux density of about 10 to15 Gauss. The device consists of several components: - ZK-PP2K High power PWM driver - 12V to 19v Pover supply unit - some type of connector to which the coil would be connected - and the therapeutic coil The heart of the device is this small module ZK-PP2K which can be purchased for less than 5 dollars." [...]
"An Ultrasonic Range Finder Using an SRF05 and an ATTiny85 An ultrasonic range finder is a useful tool in a variety of real-life and robotic applications, such as in obstacle avoidance and distance measurement systems. The ultrasonic range finder measures the distance by emitting a 40KHz pulse of ultrasonic sound that travels through the air until it hits an object, then it measures the delay of the reflected signal and sends proper commands to other units. I used an SRF05 ultrasonic sensor and an ATTiny85 microcontroller. The distance data is displayed on a 128*64 OLED screen, both in centimeters and inches. Also, a horizontal bar graph provides a visual estimation of the distance. The MCU code was developed using the Arduino IDE." [...]
"Today, we are here with an interesting DIY project, the automatic fish feeder. You might be thinking, what's new in an automatic fish feeder, right? Sit tight; we've got you a surprise. Apart from the existing automated fish feeders, this has a companion app that can control the fish feeder from anywhere in the world. You can instantly feed the fish using the "Feed Now" button. In addition, you can set your feeding schedule and change them easily using the scheduler in the companion app." [...]
"Drones are very popular toys and tools these days. You can find professional and even beginner drones and flying gadgets in the market. I have four drones (quadcopters and hexcopters), because I love everything that flies, but the 200th flight isn't so interesting and starts to be boring, so I decided that I will build my own drone with some extra feutures. I like to program Arduino and design circuits and gadgets so I started to build it. I used the MultiWii flight controller that is based on the ATMega328 chip that is also used in the Arduino UNO, so programming was pretty simple. This drone can be connected to an Android smartphone that sends its GPS data to the drone, that compares to its own GPS signal, then starts to follow phone, so if I move on the street the drone follows me." [...]
That's all Folks!