Explore further 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. Researchers from Harvard University and the University of Hawaii at Manoa recently announced a new method for organizing nanowires and carbon nanotubes across large areas: blowing bubbles. Bubble blowing, or blown-film extrusion, is a well developed technique used in industry, such as in plastic-film manufacturing, where polymers are melted and inflated into balloons that can be collapsed and cut. However, this is the first time that this approach has been used in nanoscience research. The scientists suspended each type of nanostructure in a polymer-based liquid and created large bubbles using a circular die and controlled pressure. The very thin wall of each bubble (a few hundred nanometers thick) contains an even, well organized and aligned distribution of nanostructures. When an expanding bubble is placed against a surface, the bubble wall is transferred to it. This allows a thin film with a controllable nanostructure density and pattern to be deposited onto relatively large wafers, plastic sheets, and curved surfaces.“This ability is necessary for many proposed optical and electronic applications for nanowires and nanotubes but, so far, other methods cannot be extended to the large-scale assembly of nanowires and nanotubes on both flexible and rigid substrates,” said Harvard scientist Charles Lieber, the paper’s corresponding author, to PhysOrg.com.Lieber and his colleagues worked with two types of nanowires – silicon and cadmium sulfide – and both single- and multi-walled carbon nanotubes. In each case, they were able to produce bubbles with diameters greater than 25 centimeters (cm) and heights greater than 50 cm. The films were transferred to various surfaces: a silicon wafer 20 cm in diameter, a flexible plastic sheet with dimensions of 22.5 cm x 30 cm, and a half cylinder 2.5 cm in diameter and 6 cm long.The researchers say that by using larger dies and learning how to gain greater control of the expansion process they could potentially create bubbles up to a few meters in dimension as is achieved in today’s plastic-film industry. This means that films larger than one meter across could be produced and transferred, opening up the potential of new large-area electronics applications using nanowires and nanotubes.Lieber and his colleagues illustrated this potential by using a silicon-nanowire blown-bubble film to create a large array of nanowire-based transistors on 7.5-cm-diameter plastic sheets. The transistors’ properties and performance compare to, and often exceed, those created using other assembly methods. By using higher performance nanowires, the scientists expect that significant improvements are possible.“Our method has the added advantage of being a more straightforward and efficient approach than other techniques in terms of making functional nanodevices over large areas,” said Lieber.The scientists do concede that the nanowire density and wire-to-wire distance of the silicon-nanowire film currently achieved are “modest,” but can be further increased by preparing a higher concentration polymer suspension of nanostructures. However, they say, those values are still useful for some applications, such as biological sensor arrays and display screens.This research is discussed in the May 27 online edition of Nature Nanotechnology.Citation: Guihua Yu, Anyuan Cao and Charles M. Lieber, Nature Nanotechnology, 2007, 2, 372-377.Copyright 2007 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. Citation: ‘Blown Bubble’ Method Disperses Nanostructures Over Large Areas (2007, June 22) retrieved 18 August 2019 from https://phys.org/news/2007-06-blown-method-disperses-nanostructures-large.html New technology gives insight into how nanomaterials form and grow A blown-bubble film (bubble diameter is 35 cm, height is 50 cm) that has coated the surface of two silicon wafers. Credit: Charles Lieber, et al.
Explore further (PhysOrg.com) — In order to better understand how ceramics are able to resist heat, the National Science Foundation has awarded grants totaling half a million dollars to three research groups to look into how the ancient Greeks made their pottery, a process which allowed for as many as 100,000 vases to survive from ancient antiquity to now – a period of some twenty five hundred years. The hope is that such research will reveal more about the nature of iron-spinel chemistry, which is what gives ceramics an ability to withstand heat while remaining chemically stable. Getting a better grip on how ceramics work is critical to future space flight technological efforts, as ceramics are used to help space vehicles withstand both extreme hot and cold temperatures. © 2011 PhysOrg.com Citation: NSF turns to ancient pottery to improve modern heat resistant ceramics (2012, January 4) retrieved 18 August 2019 from https://phys.org/news/2012-01-nsf-ancient-pottery-modern-resistant.html 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. Deciphering the elements of iconic pottery In order for space vehicles to work properly, they have to be able to withstand the cold of space, which can be as low as 250 degrees Fahrenheit below zero. Then, some vehicles have to be able to withstand the extreme heat of reentry, which can be as hot as 3000 degrees. Hot enough to melt most any metal. As most know, the Space Shuttle was fitted with ceramic tiles on its underbelly to keep the vehicle from overheating as it came back to Earth, which was made all the more apparent when damage to the tiles resulted in the loss of Columbia in 2003. But ceramics are used in other components as well, and will be needed as more ambitious projects are undertaken in the future. Equally important is the ability of ceramics to remain chemically unchanged when subjected to such temperature variations. Such properties allow for the construction of components that minimize expansion and contraction under such stresses, which can be critical for long term operations in space. This is why the NSF has turned to research scientists to see if the ancient Greeks can provide some insight.Such research will involve using something called x-ray absorption near edge structure (XANES) – which is a special type of spectroscopy, along with other types of x-ray techniques, to find out what has gone on with iron oxidation in the pottery under study. What’s needed is a better understanding of the molecular structure of iron minerals that were used to make the pottery to help researchers in designing newer and better types of ceramics for future space missions, whether manned or otherwise.What’s interesting is that it is apparently the degree to which the iron in the ancient ceramic pottery oxidized that caused the distinctive red and black colorations that made it so attractive to those that worked with it all those years ago.
Explore further Citation: Ukraine team wins Imagine Cup with gloves that convert sign language to speech (2012, July 11) retrieved 18 August 2019 from https://phys.org/news/2012-07-ukraine-team-cup-gloves-language.html The team said the idea for their system came from the frustration they experienced when trying to communicate with hearing impaired athletes at their school. They also noted that the system can be easily tweaked by the user to incorporate custom signs and thus can be used for virtually any sign language dialect. The point they say is to help those with hearing impairments better manage in the world of the hearing. The problem with sign language they point out, is that most people who can hear never learn it, thus those with hearing impairments are only able to communicate with a small part of the general population which generally includes those who cannot hear and those in their immediate circle. This new system they say, will allow those with hearing impairments to communicate with anyone.
© 2013 Phys.org Citation: Crowd sourcing project to allow 3D scan-to-print web app (2013, August 5) retrieved 18 August 2019 from https://phys.org/news/2013-08-crowd-sourcing-3d-scan-to-print-web.html Explore further Technology to allow for printing three dimensional objects is evolving rapidly, making it difficult for some to keep up. It’s also still relatively expensive. Currently, people who wish to print such an object have but two choices—buy (or borrow) a 3D printer or contract out with a company that prints 3D objects for a price. Both options require software and a depth camera. Now it appears a third option is about to make its debut—one that might make the entire process both cheaper and far easier to carry out. BotObjects announces first full color 3D printer— ProDesk3D Volumental, a company that is currently accepting image data captured via depth camera, printing 3D models and shipping them back, is now looking to create a web based app to replace the software portion of the process. That would mean anyone with a depth camera (which includes Kinect devices) could scan an object, have it rendered onscreen and then sent to a 3D printer of their choice. If successful, a new way to print 3D objects could become as common as printing text and images on a piece of paper. The company has set up a Kickstarter project with a goal of reaching $20,000 to finish writing the web app code—pledges so far are just over half that amount.As depth cameras (those with two or more lenses) become more common, demand for 3D printing grows, though currently printers able to do so are still quite expensive. If, however, consumers that have already purchased a Kinect device for gaming can use their existing equipment along with what is essentially free software to capture the object data, then half the process of producing 3D models is covered. An added advantage to such a system would be a reduction in difficulty in capturing the 3D image. Users could conceivable load the browser scanner, spin slowly in place in front of their Kinect device, place an order with Volumental (or have the data sent to another site, such as the local 3D printer at work) and wait for the full color model to arrive at their home. Objects captured would be limited only by the range of the camera—users could conceivably scan every object in their living room, including furniture and have it printed in a size limited only by the ability of the printer to which it is sent. As printer technology improves, so too will the range of materials that can be used as “ink” opening up the door to some pretty amazing possibilities. 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.
The evening started with the short introduction by Ashok Vajpayee, followed by short word on Kraków and literature by Prof Piotr Klodkowski.Piaskowski took the audience through a presentation on Krakow City of literature. Urvashi Butalia made contemporary remarks on the literature of both the cities. Michal Rusinek gave an insight into the Krakow literature. The event was concluded with an interactive discussion with the audience.After a three-year wait, Kraków become the UNESCO City of Literature, 21 October 2013. Kraków is the seventh city to be granted this honour, following Edinburgh, Melbourne, Iowa City, Dublin, Reykjavík and Norwich. Also Read – ‘Playing Jojo was emotionally exhausting’Kraków receiving the title of UNESCO City of Literature bears testament to the cultural heritage of our ancient city and the wealth of its artistic life today.Kraków has long been an academic and intellectual centre of Europe and a cradle of language and literature; it was the first Polish city to hold scriptoriums, libraries and printing houses, and it is the birthplace of scores of literary masterpieces. It was also home to the authors of Polish modernism – Stanislaw Wyspianski, Stanislaw Przybyszewski and Józef Mehoffer – and more contemporary artists including Karol Wojtyla, Tadeusz Kantor, Stanislaw Lem, Slawomir Mrozek and Andrzej Wajda. It was here that Czeslaw Milosz (awarded the Nobel Prize in Literature in 1980) returned after many years in exile, and it was the home of Wislawa Szymborska (Nobel Prize in 1996) throughout her long life until her passing in 2012.
How do you define sexiness? What is sexy?, ‘From an infectious smile of Madhu Bala to the poised grace of Zennat Aman; dancing swirls of Madhuri Dixit and to the zero figure of Kareena Kapoor, everything is sexy! It has nothing really to do with how they dress up,’ said fashion critic and journalist, Reena Dhaka during a discussion in Oxford bookstore.‘Is being sexy anti-sexist?’, ‘Does dressing up in a sexy manner define a woman’s mindset?’ were some of the pertinent questions that were raised during the engaging conversation. An audio-visual presentation seeking responses from various women with different backgrounds attempted to answer these questions. They all were asked one question and that was, if they dress-up for others? The unanimous answer was an outright ‘No’. Also Read – ‘Playing Jojo was emotionally exhausting’The discussion attracted quite an ethusiastic crowd who were of the opinion that they dressed-up for themselves and no one else.The key speakers of the conversation, fashion designer, Rina Dhaka and Vinita Dawra Nangia discussed how dressing-up sexily does not really mean that one is easy or available. Nangia further said, ‘To even ask such a question would hint at sexism.’ The rape victims in this fairly sexist society are often slapped with a counter-argument as to how they deserve what hapened to them because they asked for it. When you ask them how? They will promptly reply with, ‘Of course, because of the clothes they wore.’ No one asks for violence, no one wants to get beaten up or raped, no matter what you wear. Also Read – Leslie doing new comedy special with NetflixDhaka said being a woman she has to confirm to various roles in a day and is expected to dress aprropriately for all the ocassions. She asked, ‘How can you expect a woman to dress appropriately throughout the day for varied ocassions. Isn’t that hectic? To dress three to four times a day? Just because people think it’s inappropriate to step out in a dress outside in the public?’ She said that dressing-up has nothing to do with sexiness. The definition has changed. It’s all in one’s attitude and the way they feel they are, not the way they dress. However, Dhaka’s ‘When in Rome, do like Romans’ comment did not strike well. She said, ‘In India, it is very important to select a dress according to the place and environment. There is no harm in carrying a shrug or a scarf, which you can easily take off once surrounded with a like minded people.’ The question this comment raises and remained unaswered was, why does one need to carry a scarf around? Instead of being preventive, why can’t we strive to change the mindset which compels us to carry a scarf with us?
Artist Puneet Kaushik presents his latest series of works titled Daraar – Beneath the Faultline at India Art Fair from January 29 to February 1. The works reflect no longer something remote, but abstractions of life itself. Kaushik’s bodies of work are aesthetic and material dimensions of extractions, accumulation, territorialisation, condensations and fractures underlying the visible reality of urban life. They are neo-expressionist, collages of kaleidoscope materials and techniques – wire mesh, paint, bead work, carpet craft, line drawings and organic dyes that bring to the surface histories of tension that exist just beneath the ordinariness of everyday lived humanity. Also Read – ‘Playing Jojo was emotionally exhausting’Known for using methodologies and traditional techniques incorporating tribal and folk art like the works are of steel wire mesh, woven hibiscus and coffee stains on paper, natural dyes, tufting the carpet technique, dabkha and bead work.In his works, Puneet has been successfully driven by a single idea or concept, injecting an element of exploration, with materials offering their own guiding agency; and in this respect he marks a posture of difference. Also Read – Leslie doing new comedy special with NetflixThe guiding concept behind the majority of the works has been around the idea of Identity, the dealing with the self. The beauty and the ugliness within the surface; the superficial and the deeper self, textured and layered by different circumstances where it is rare to be in a position to penetrate into the real self.Puneet has been intrigued by age-old traditional techniques like knitting, crochet and embroidery, rooted deep in our cultures as a means of talking about the self. For example, the traditional Tibetan technique using a process of embroidery where two or more beads are stitched in one go was normally done not only to enhance the jewellery or crown but also to thicken the surface in order to protect and keep one warm.When: January 29 to February 1Where: Booth S-5, India Art Fair, NSIC Exhibition Grounds
Athlete Lolo Jones has slammed erotic romantic drama film Fifty Shades of Grey, saying people should boycott the movie because it glamourises unholy sex. “Funny how some people think there’s nothing wrong with 50 shades of Grey. God didn’t create sex for that purpose. Watch another movie,” she posted on Twitter Tuesday about the Dakota Johnson and Jamie Dornan-starrer, reports tmz.com. Jones, who’s also a devout Evangelical Christian explained that the film’s hypersexual plot can make people feel that sex for pleasure is the answer to emotional pain.