This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Citation: Nanoball Batteries Could Charge Electric Cars in 5 Minutes (2009, March 12) retrieved 18 August 2019 from https://phys.org/news/2009-03-nanoball-batteries-electric-cars-minutes.html A sample of the new battery material that could allow quick charging of portable devices. Image credit: Donna Coveney. Explore further Byoungwoo Kang and Gerbrand Ceder of MIT have improved the design of a “nanoball battery,” which has a cathode that is composed of nanosized balls of lithium iron phosphate. As the battery charges, the nanoballs release lithium ions that travel across an electrolyte to the anode. As the battery discharges, the opposite occurs, and the lithium ions are reabsorbed by the nanoballs in the cathode. The key to the nanoball battery’s quick charge time is the speed at which the lithium iron phosphate nanoballs in the cathode can release and absorb lithium ions. In conventional lithium ion batteries, detaching the ions from the normal cathode takes a relatively long time. By coating each nanoball with a thin layer of lithium phosphate, Kang and Ceder showed that they could detach the lithium ions from the nanoballs even quicker than previous studies have found. To demonstrate the technology, the researchers fabricated a small battery that could be fully charged or discharged in 10 to 20 seconds, which would otherwise have taken six minutes. The scientists’ tests showed that the new material degrades less than other battery materials after repeated charges and discharges. This means that the battery could be made with less material, which could possibly lead to smaller, lighter batteries.More information: Byoungwoo Kang and Gerbrand Ceder. “Battery materials for ultrafast charging and discharging.” Nature 458, 190-193 (12 March 2009), doi:10.1038/nature07853.© 2009 PhysOrg.com New battery material could lead to rapid recharging of many devices (PhysOrg.com) — Researchers at MIT have designed a new battery that can recharge devices about 100 times faster than conventional lithium ion batteries. The design could lead to electric car batteries that charge in 5 minutes (compared with 8 hours in today’s electric cars) and cell phone batteries that charge in just 10 seconds.
(PhysOrg.com) — “Scientists have been making Bose-Einstein Condensates [BECs] for nearly 15 years,” Charlie Doret tells PhysOrg.com. “Essentially all BEC research to date, however, begins with laser cooling. Unfortunately, laser cooling is impractical for some atoms, and it is especially difficult with molecules, limiting the scope of new research.” This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Citation: Buffer gas cooling could open up the field of ultracold physics (2009, September 17) retrieved 18 August 2019 from https://phys.org/news/2009-09-buffer-gas-cooling-field-ultracold.html Explore further Scientists Announce First Observation of ‘Persistent Flow’ in a Gas In order to create a more general method for producing ultracold atoms and molecules, Doret, a graduate student at Harvard University, worked with a team to develop a method of buffer-gas cooling that would work for many different atoms and even for many molecules. “Our process is more general than laser cooling,” he explains. Along with Colin Connolly and John Doyle at Harvard and Wolfgang Ketterle at MIT, Doret believes that their more widely applicable technique will enable creation of BECs with new atoms and molecules. Their work can be found in Physical Review Letters: “Buffer-Gas Cooled Bose-Einstein Condensate.” To make BECs with ultracold atoms and molecules, an initial cooling and trapping stage is needed. The atoms or molecules in question are cooled to a point where they are moving slowly enough to be trapped. Once they are trapped they can be cooled further, leading to Bose-Einstein condensation. BECs are useful in a number of experiments, and have potential practical applications due to their similarities to laser light. “Unfortunately,” Doret points out, “laser cooling just doesn’t work well for some stuff.” In laser cooling, photons are sent to bombard the atom in such a way that it eventually slows down, via a scattering process. Doret explains that this technique is similar to using golf balls to slow down a bowling ball. “It works eventually, but it takes a lot of photon scattering events to slow an atom, just as you would expect to use a great many golf balls to effectively slow a bowling ball.” Instead of using lasers to slow down an atom, Doret and his peers opted for using a buffer gas. “We have a cold gas that we can bounce off of hot atoms. Collisions with this buffer gas cools the atoms, making them easier to magnetically trap, after which they can be further cooled until they Bose-condense.” For the current experiment, the Harvard and MIT team used cooled helium gas as a buffer to cool metastable helium atoms. “We have demonstrated the process from start to finish with atoms, but we haven’t done it with molecules. But the principle should be the same, and our next attempt will probably be to attempt to use buffer-gas cooling – with a few little tweaks – to create a BEC of the NH molecule.” A general path to BEC with molecules would be a huge step forward for ultracold physics, Doret insists. “One big effect it could have is for the possibility of building a quantum computer. One way that has been suggested is to take polar molecules and trap them in an optical lattice, using the cold molecules as qubits. Due to the difficulty of laser cooling molecules, getting polar molecules into a lattice is a challenging but important step. Buffer-gas cooling could work, though.” In the end, Doret believes that buffer-gas cooling could provide the means to experiment further with BECs and other subjects of interest. “Buffer-gas cooling allows us to use atoms and molecules not accessible in the past. There are new applications to pursue, and more tools that can be brought into play. This could open up the entire field of ultracold physics.” More information: Doret, et. al. “Buffer-Gas Cooled Bose-Einstein Condensate,” Physical Review Letters (2009). Available online: http://link.aps.org/doi/10.1103/PhysRevLett.103.103005. Copyright 2009 PhysOrg.com. All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com.
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Citation: Seabird’s morphing wings inspire design for robots that can both fly and swim (2010, November 19) retrieved 18 August 2019 from https://phys.org/news/2010-11-seabird-morphing-wings-robots.html (PhysOrg.com) — There are robots that can fly, and there are robots that can swim, but so far a robot that can both fly and swim does not exist. With the goal to design an aerial/aquatic robotic vehicle, a team of researchers is investigating how nature achieves both aerial and aquatic motion in a single entity, particularly in a seabird called the common guillemot. They plan to use their calculations, models, and simulations to design a robotic vehicle with a morphing wing similar to the one used by the seabird. Copyright 2010 PhysOrg.com.All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com. Explore further A robotic vehicle with the ability to fly and swim could have a variety of applications. For example, the vehicle could be used to inspect underwater oil pipes while flying to and from remote oil rigs. It could also be used for aerial and aquatic surveillance for counter-terrorism purposes. Variations in the missions could require very different operating speeds in each medium. The numerical model developed by the researchers takes these issues into consideration and can provide mission-specific optimal values to use in future concept vehicle designs. Currently, the researchers are developing an experimental platform from which they can investigate various parameters associated with flapping propulsion during aquatic locomotion.As Lock noted, there are still several challenges that need to be addressed, starting with the need to better understand the performance compromise between operations in the air and water due to the fact that robots of this type have not yet reached a level of maturity within the research community. “The second biggest challenge that we face is one that everybody within the robotics community has to deal with, and that is the problem of a suitable power source,” he said. “There is of course a finite payload which any robotic vehicle can carry, of which the power source invariably contributes a significant proportion of the overall mass. Implementing a power source that is light enough to allow aerial operations but provides sufficient power to enable the use of the locomotion mechanisms for any feasible length of time is a huge problem that we face. Luckily this is a common problem faced by many robots whereby the ultimate aim is for the untethered operations and as such many research groups are striving towards new power sources with greater power-to-weight ratios and lifespans. Although not currently available, we believe that in time a suitable power source will be developed that allows aerial/aquatic vehicles to be developed.“Finally, the third challenge we face comes from developing a vehicle of this scale capable of aerial operations utilizing beating wing flight. Very few mature examples exist that achieve this mode of locomotion through a flapping locomotion strategy, and they are not attempting operations in water as well. Solutions to this problem do exist, such as the inclusion of an additional propulsion source for use whilst in air such as a propeller, but this then moves away from the biological example from which the work drew inspiration. However, we are not ruling this out as a stepping stone whilst addressing other elements of the complex task that we face.” The common guillemot flies with straight wings and swims with bent wings, which reduces profile drag by up to 50%. This strategy is providing inspiration for the design of aerial/aquatic robotic vehicles. Image credit: Lock, et al. Adapted from unpublished BBC footage.) Micro flying robots can fly more effectively than flies More information: Richard J. Lock, et al. “Development of a biologically inspired multi-modal wing model for aerial-aquatic robotic vehicles through empirical and numerical modelling of the common guillemot, Uria aalge.” Bioinsp. Biomim. 5 (2010) 046001 (15pp). DOI:10.1088/1748-3182/5/4/046001 Researchers Richard Lock, who is working under the supervision of Dr. Ravi Vaidyanathan at the Bristol Robotics Laboratory, University of Bristol, and coauthors, have published their investigation of the common guillemot’s locomotive abilities in a recent issue of Bioinspiration & Biomimetics. “The capacity to mathematically model the morphological shifts the bird makes from aerial to aquatic media is our first step in being able to reproduce the process,” Lock told PhysOrg.com. “Understanding locomotion in a single medium is already a complex problem to solve; therefore, attempting to further our understanding of systems with a multi-modal capability, i.e., operations in two different media, provides many challenges. Our work focuses on trying to understand this balance between the different media, focusing on how different mission requirements present different compromises in performance.”As the researchers explained, a variety of birds and insects are capable of locomotion in both air and water. However, these animals are confronted with numerous physiological challenges, due primarily to the fact that water is some 800 times denser than air. The animals’ locomotive strategies that solve this problem can generally be divided into two categories: two different mechanisms for the two different media, or a single mechanism adapted for both media. The common guillemot falls into the second category, as it flaps its wings for locomotion in both media. However, the bird modifies its wing shape when swimming by folding part of its wing. This simple change results in a reduction of surface area, which, as the researchers calculated, reduces profile drag by as much as 50% and significantly reduces the overall power requirements. This ability enables the common guillemot to nest on land along the coast, fly up to 30 km out to sea, dive underwater, and flap its wings to swim and hunt for marine food. After developing a model of the common guillemot’s wing size, shape, and flapping behavior, the researchers validated the model with simulations. Their goal was to find the values of key variables that achieve the highest performance (i.e., the lowest energy requirements) for a robotic vehicle that could fly with a range of 2 km at a velocity of 20 m/s and swim with a range of 500 m at a velocity of 1.5 m/s. These values are similar to that of the typical feeding habits of the common guillemot. The model’s suggested values for key geometric and kinematic parameters were in close agreement to those exhibited by the guillemot, providing the researchers with preliminary validation of their numerical model. The model can also be used for additional missions based on projected uses of the concept vehicle.
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. PausePlay% buffered00:0000:00UnmuteMuteDisable captionsEnable captionsSettingsCaptionsDisabledQuality0SpeedNormalCaptionsGo back to previous menuQualityGo back to previous menuSpeedGo back to previous menu0.5×0.75×Normal1.25×1.5×1.75×2×Exit fullscreenEnter fullscreen Citation: Monkeys have better basic counting skills than originally thought (2011, March 31) retrieved 18 August 2019 from https://phys.org/news/2011-03-monkeys-basic-skills-thought.html Play A monkey choosing and obtaining the reward in the ‘Food’ condition. Image credit: NPG, doi:10.1038/ncomms1262 Researchers point out that these natural impulses in the monkeys and their desire to eat the raisins interfered with their judgment in the initial experiment. Similar to young children and the reverse reward paradigm, these monkeys were not able to see past their desire to eat the raisins.In the reverse reward paradigm, young children are presented with two piles of candies of different sizes. The children will always point to the larger pile and then this pile is given to another child. Children have difficulty understanding that by choosing the smaller pile, they will receive the larger pile. However, if this test is repeated with non-edible objects, the children are able to understand and perform the experiment correctly.Researchers in this study point to the same interference in judgment by the monkeys when presented with food. Their desire to eat the food gets in the way of the task at hand. These researchers believe that previous studies performed on other primates using food as a test symbol may have impaired results and therefore underestimated the primate’s numeracy abilities. © 2010 PhysOrg.com Macaca fascicularis, long-tailed macaque. Photo credit: Roy Fontaine Island monkeys do not recognize big cat calls More information: Representational format determines numerical competence in monkeys, Nature Communications 2, Article number: 257 doi:10.1038/ncomms1262 , Published 29 March 2011 Explore further Researchers, led by Vanessa Schmidt from the German Primate Center in Goettingen, Germany, conducted basic numeracy tests on long-tailed macaques in an effort to show that these primates understand the concept of relative quantity.In the first experiment, researchers presented the monkeys with two plates of raisins with one having more than the other. The idea being that the monkeys would choose the plate with the larger number of raisins. In this first experiment, the monkeys were then allowed to eat the raisins on the plate they choose. In this experiment, researchers found that the monkeys had a tendency to get this wrong and chose the plate with the smaller amount of raisins.In the second experiment, the researchers decided to replace the raisins with non-edible objects, in this case pebbles. When presented these plates with pebbles, the monkeys did much better.The third experiment returned to the plates with raisins, but instead of being rewarded with the raisins on the plate, the monkeys were rewarded with raisins hidden underneath. This experiment showed the same results as the pebbles. (PhysOrg.com) — In a recent study published in Nature Communications, it appears that Old World monkeys have the ability to count better than was originally thought. The research also shows that when presented with counting tasks, these long-tailed macaques are very similar to children in suppressing their impulses.
Citation: Berkeley robot uses tiny, spiny toes to climb cloth (2011, October 10) retrieved 18 August 2019 from https://phys.org/news/2011-10-berkeley-robot-tiny-spiny-toes.html The lab’s creation, CLASH, is the newest member of its robotic creatures, and this one moves vertically up cloth. Ten centimeters long, the 15-gram CLASH moves up cloth fast in an insect-like scurrying motion. The motor in CLASH powers the legs and drives its swift gait frequency. According to the Biomimetic Millisystems Lab site, the robotic device “is capable of climbing a loose cloth surface at 15 cm per second using a simple passive claw mechanism and a coupled in-plane leg drive system.”Each leg is connected to the single motor through a series of linkages. A point of design interest about CLASH is centered on the gripping and climbing technique the team devised, where tiny spikes on the robit’s feet grip into loose fabric and let the bot climb. The electronics and battery are configured into the tail of the robot, which adds balance. The CLASH newcomer belongs to the lab’s family of “Ambulating Robots.” They make a case for the value of legged systems rather than wheeled systems. Key performance advantages in legged systems is because the feet are not continually in contact with the ground, which makes legged robots better able to cross challenging terrain, they note. Perhaps the most interesting advantage, say the researchers, is in dynamic behavior seen in nature. “Many legged animals exhibit dynamically, self-stabilizing behavior. That is, the passive mechanical properties of the systems are tuned to naturally reject disturbances which might otherwise cause unstable behavior in the system.”Last month the Berkeley team of P. Birkmeyer, A. G. Gillies, and R. S. Fearing presented “CLASH: Climbing Vertical Loose Cloth” at IROS 2011 (International Conference on Intelligent Robots and Systems) in San Francisco.The lab’s work on CLASH is not done yet. According to a report in IEEE Spectrum, they want to get CLASH to crawl horizontally, and they want CLASH to turn. (PhysOrg.com) — Scientists working in robotics know that nature holds the best ideas for making robots that can perform with speed, agility, and efficiency. At University of California, Berkeley, the Biomimetic Millisystems Lab is at the forefront of mimicking nature. Its lab mission is “to harness features of animal manipulation, locomotion, sensing, actuation, mechanics, dynamics, and control strategies,” in its work with small lightweight millirobots. © 2011 PhysOrg.com Explore further Can MRI drive a medical robot? This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Citation: Study suggests multiple instances of inter-breeding between Neanderthal and early humans (2018, November 27) retrieved 18 August 2019 from https://phys.org/news/2018-11-multiple-instances-inter-breeding-neanderthal-early.html A pair of researchers at Temple University has found evidence that suggests Neanderthals mated and produced offspring with anatomically modern humans multiple times—not just once, as has been suggested by prior research. In their paper published in the journal Nature Ecology and Evolution, Fernando Villanea and Joshua Schraiber describe their genetic analysis of East Asian and European people and how they compared to people from other places. Fabrizio Mafessoni with the Max Planck Institute for Evolutionary Anthropology offers a News and Views piece on the work done by the pair in the same journal issue. More information: Fabrizio Mafessoni. Encounters with archaic hominins, Nature Ecology & Evolution (2018). DOI: 10.1038/s41559-018-0729-6Fernando A. Villanea et al. Multiple episodes of interbreeding between Neanderthal and modern humans, Nature Ecology & Evolution (2018). DOI: 10.1038/s41559-018-0735-8 Explore further Modern humans inherited viral defenses from Neanderthals Journal information: Nature Ecology & Evolution Comparison of Modern Human and Neanderthal skulls from the Cleveland Museum of Natural History. Credit: DrMikeBaxter/Wikipedia In recent years, scientists have discovered that early humans moving out of Africa encountered Neanderthals living in parts of what is now Europe and Eastern Asia. In comparing Neanderthal DNA with modern humans, researchers have found that there was a least one pairing that led to offspring, which is reflected in the DNA of humans—approximately 2 percent of the DNA in non-African humans today is Neanderthal. In this new effort, the researchers have found evidence that suggests there was more than one such encounter. Their findings make logical sense, considering that anatomically modern humans and Neanderthals coexisted for approximately 30,000 years. Recent research by other groups had suggested that multiple offspring-producing unions had occurred—some people in East Asia, for example, were found to have up to 20 percent more Neanderthal DNA than people of strictly European descent. In this new effort, the researchers took a more stringent look to find out once and for all if there had been multiple pairings or just one. They pulled and analyzed data from the 1000 Genomes Project, measuring the amount of Neanderthal DNA in genetic material from volunteers. The first step was separating the data between people of European and Asian ancestry. Doing so suggested that both groups had evidence of early multiple mating events. The researchers then studied the rates of the two groups by creating simulations showing outcomes of differing numbers of mating events between the two groups. Data from the simulations was then fed into a machine-learning algorithm that showed DNA percentage patterns based on the number of cross-breeding events that had occurred.The researchers concluded that the most likely scenario was that there were multiple instances of cross-breeding between early humans in both East Asia and Europe with Neanderthals. © 2018 Science X Network
Some scientists are truly extraordinary mentors. Take, for example, professor Charlotta Turner, a chemist at Lund University in Sweden, who in 2014 received a text from her Ph.D. student telling her that he might not finish his thesis in time. When she learned that her student, Firas Jumaah, was in fact hiding with his family in an Iraqi factory as armed members of the Islamic State group roamed the streets outside, she leapt into action and worked with the university’s security chair to arrange a daring rescue operation. But for every heroic mentor, there are just as many horror stories about bad ones. Unfortunately, most mentors don’t always have the tools or training to provide the proper support to their mentees (and, unfortunately, some just don’t care). Becoming a better mentor should be a central concern for new faculty members starting their own labs, but also for graduate students and postdocs mentoring research assistants—and even for more senior faculty members who are continually striving to improve their mentoring. Our capacity for growth as mentors is a lifelong journey. Read the whole story: Science One way to address this issue is by learning the science behind great mentoring, as Jay and colleagues discussed on a panel recently. Instead of relying solely on personal anecdotes or their own gut intuitions, the panelists described theories and research on how to manage the most important relationship in science: the one between a mentor and mentee. Here, we share three lessons from that event.
The Fourth Dastkar Basant Bazaar, 2013 edition in partnership with Delhi Tourism, a Spring Festival showcasing crafts and craftspeople from all over India, is on full flow at Dastkar’s permanent venue in Andheria Modh, Chhattarpur. The bazaar has been on from 22 February and will be on till 10 March, daily from 11:00 am to 7:00 pm. The festival brings together around 160 craft groups from over 20 states, with around 15 new designers, representing a wide range of authentic quality handlooms and handicrafts. Also Read – ‘Playing Jojo was emotionally exhausting’As spring breathes new life into nature, the Basant Bazaar will present the many beauties of regional crafts and textiles, so often created in dusty, earthy conditions. Like the lotus the does the beauty of the finished handcrafted products emerge from humble clay, bamboo cane, grass and coconut fibres, cotton yarns and silk worm cocoons, transformed by the skilled hands of craftspeople across the country.Dastakar has always worked to empower women and support the central role and capacities of craftswomen in particular. As part of a current breast cancer awareness campaign, The Indian Cancer Society will also be present at Basant Bazaar to disseminate information.Basant Bazaar has on offer interactive workshops and craft demonstrations that will delight. Alongside there are a mouth-watering selection of regional food stalls.DETAILAt: Nature Bazaar, Kisan Haat, Anuvrat Marg, Andheria Modh, Chhattarpur When: On till 10 March Timings: 11:00 am to 7:00 pm
West Bengal Chief Minister Mamata Banerjee, who had extended her support to Aam Aadmi Party (AAP) convener Arvind Kejriwal days before the poll date, congratulated him for the unprecedented victory. Hailing the victory, Banerjee tweeted, “My congratulations to all the Delhi voters, AAP workers and leaders for big victory. Well done to you. All my best wishes. We are very happy.”While taking a dig at Prime Minister Narendra Modi, Banerjee tweeted, “This is a victory for the people and a big defeat for the arrogant and those who are doing political vendetta & spreading hate among people.” The West Bengal CM, in her tweet, also said, “Delhi elex is turning point of present political situation. Shows political vendetta has no place in a democracy. Country needed this change.” Also Read – Need to understand why law graduate’s natural choice is not legal profession: CJINotably, a few days ahead of Delhi polls, the Trinamool Congress (TMC) president had issued a statement asking her supporters and voters to support Kejriwal for the development of Delhi. Banerjee had tweeted, “My request to all of you in Delhi is to please vote for AAP… for the greater need of the country and development in Delhi.” The TMC chief’s call for support to AAP is in the line with her policy for a “federal front” comprising of regional parties, including JD(U), BJD, SP, JD(S), CPI, etc. Also Read – Health remains key challenge in India’s development: KovindFormer Bihar CM and JD(U) leader Nitish Kumar, who had also extended his support to AAP, congratulated Kejriwal for registering a landslide victory in Delhi. On AAP victory, Kumar said, “People want development with justice. They never accept arrogance. This is reflected in AAP’s victory in Delhi.”Other leaders who had supported AAP in Delhi polls include national Conference leader Omar Abdullah, former Prime Minister HD Deve Gowda and CPI(M) general secretary Prakash Karat. JD(S) leader Gowda, a probable constituent of Mamata’s Federal Front, had asked their activists and supporters to back AAP wherever its candidates were not in the running.
The Portret Project aims to create a participatory project in which viewers and participants work with teamtpp to pick pieces of art from our studio install it at the AntiSocial in Hauz Khas Village. The collaborative experience begins at their studio in Vasant Vihar and through a process of cumulative ideating, hopes to make the participants engage with the works of art and the space. In doing so, unexhinition hopes to make the audience the enablers of the art experience rather than merely passive viewers. Also Read – ‘Playing Jojo was emotionally exhausting’Right from selecting the artworks, to setting up the installation at AntiSocial, the audience creates the experience. The installation will happen over 6 days starting on March 22. Viewers and participants are invited to join teamtpp at their studio in Vasant Vihar every day and eventually take the selected art to install it on the walls of Social. The Portret Project and Social Offline will conclude the process by hosting an event on the March 28 to show people a spacetransformed by art and share our stories.