Scientists have discovered a new method to convert dried tree leaves into a porous carbon material that can be used to produce high-tech electronics. Researchers from Qilu University of Technology in China used a multi-step, yet simple, process to convert phoenix tree leaves into a form that could be incorporated into electrodes as active materials.
The dried leaves were first ground into a powder, then heated to 220 degrees Celsius for 12 hours. This produced a powder composed of tiny carbon micro spheres. These micro spheres were then treated with a solution of potassium hydroxide and heated by increasing the temperature in a series of jumps from 450 to 800 degrees Celsius.
The chemical treatment corrodes the surface of the carbon micro spheres, making them extremely porous. The final product, a black carbon powder, has a very high surface area due to the presence of many tiny pores that have been chemically etched on the surface of the micro spheres.
The high surface area gives the final product its extraordinary electrical properties, said Hongfang Ma of Qilu University of Technology, who led the study published in the Journal of Renewable and Sustainable Energy. The researchers ran a series of standard electrochemical tests on the porous micro spheres to quantify their potential for use in electronic devices.
The current-voltage curves for these materials indicate that the substance could make an excellent capacitor. Further tests show that the materials are, in fact, supercapacitors, with specific capacitances of 367 Farads/gramme, which are over three times higher than values seen in some graphene supercapacitors, researchers said. A capacitor is a widely used electrical component that stores energy by holding a charge on two conductors,separated from each other by an insulator.
Supercapacitors can typically store 10-100 times as much energy as an ordinary capacitor, and can accept and deliver charges much faster than a typical rechargeable battery. For these reasons, supercapacitive materials hold great promise for a wide variety of energy storage needs, particularly in computer technology and hybrid or electric vehicles.
The supercapacitive properties of the porous carbon microspheres made from phoenix tree leaves are higher than those reported for carbon powders derived from other bio-waste materials, researchers said. The fine scale porous structure seems to be key to this property, since it facilitates contact between electrolyte ions and the surface of the carbon spheres, as well as enhancing ion transfer and diffusion on the carbon surface.
Bose Frames AR Audio Sunglasses Launched in India, Priced at Rs. 21,900
Over a year after originally showcasing its audio AR sunglasses, Bose is bringing them to the Indian market. The company on Thursday announced that the sunglasses, which are simply known as Bose Frames, will go on sale beginning next week in the country alongside Bose Frames Lens Collection. The Bose Frames combine three functionalities into one device – premium sunglasses, wireless headphones, and audio AR features. The Bose Frames are the company’s first product to be based on the company’s AR platform.
The Bose Frames carry a price tag of Rs. 21,900 and will be offered in two universal styles – the larger Alto and the smaller Rondo. The Bose Frames Lens Collection of non-polarised and polarised lenses will retail at Rs. 1,990 and Rs. 2,990, respectively. The sales open June 20 via select resellers and Bose stores in the country.
The Bose Frames are essentially a pair of sunglasses that pack a tiny Bose audio system in the temples. This audio system effectively turns them into a wireless pair of headphones. The Bose Frames also include a microphone and multi-function button on the right temple for power and pairing, Siri and Google Assistant, calls and commands, or to pause and skip songs.
“With a proprietary open-ear design, they [Bose Frames] take micro-acoustics, voice control, and personal audio to an entirely new level, so users can stream music and information, take and make calls, and access virtual assistants from — while keeping playlists, entertainment, and conversations private,” Bose said in a statement.
Like many wearable devices, the Bose Frames act as a companion device to your smartphone and need the same for processing the information and connecting to the Web.
As we mentioned earlier, the Bose Frames will be released in two designs – Alto and Rondo. Alto is square and angled, whereas Rondo is round and smaller. Both can block up to 99 percent of UVA/UVB rays and weigh just 45 grams. The lenses can be easily popped out and replaced.
Apart from the audio capabilities, the Frames are also compatible with Bose’s AR platform. The Bose Frames don’t include any visual AR capabilities, but they can provide audio AR input to enhance your experience.
“[Bose Frames] knows where you are and what you’re facing using a 9-axis head motion sensor and the GPS from your iOS or Android device — and automatically adds a layer of audio through Bose AR apps, connecting that place and time to endless possibilities for travel, learning, entertainment, gaming, and more,” Bose explained.
Bose AR apps can be downloaded using Bose Connect app and are only available for iOS right now. Android apps are being developed, according to the company’s website.
The company claims that onboard battery can last up to 3.5 hours for playback and up to 12 hours on standby. It can be fully recharged in less than two hours.
Novel device can quickly detect strokes
Scientists have developed a device that can monitor blood flow and help quickly diagnose and treat strokes.
A stroke, one of the leading causes of death worldwide, occurs due to poor blood flow to the brain — a condition known as cerebral ischemia.
Its diagnosis must be done within the first few hours for treatment to be effective, researchers said.
The hybrid device, developed by researchers at the China Academy of Engineering Physics and Army Medical University in China, relies on a combination of to light measuring techniques which could diagnose cerebral ischemia non-invasively and faster than the techniques used currently.
“We can measure blood volume, blood oxygenation and blood flow using suitable near-infrared techniques,” said Liguo Zhu, from China Academy of Engineering Physics.
Zhu said that “near-infrared light penetrates one to three centimetres and allows researchers to probe under the skin.”
The working of the instrument relies on the combination of the near-infrared diffuse optical spectroscopy, which analyses the light scattered from the tissues to calculate the amount of oxygen and blood within an area, and the diffuse correlation spectroscopy, which analyses fluctuation in the tissue-scattered lights to measure blood flow.
“Both techniques share the same detectors, which decreases the number of detectors compared to other instruments,” said Zhu.
“The team’s device can record a comprehensive profile of a body part’s hemodynamics, or blood circulation. Devices should measure as many ‘hemodynamic parameters’ as necessary to obtain an accurate diagnosis, as ‘the hemodynamics of stroke is complex’,” said Hua Feng, from Army Medical University.
Another advantage of the device is that it is cheap and compact, which would make more accessible to the people, and hence, help treatment, diagnosis and chances of stroke, researchers said.
Parineeti ‘still learning’ to play badminton
Actress Parineeti Chopra has not started shooting for ‘Saina’ yet and says she is still learning how to play badminton.
Parineeti on Thursday said that the shooting for the biopic will commence in October.
“Hi everyone, we have not started the shoot of ‘Saina’ yet. I am still learning how to play Badminton! We will start in October once I get better at it! Four months to go,” she tweeted.
Parineeti had replaced actress Shraddha Kapoor in the Saina Nehwal biopic, which is being directed by Amole Gupte.
She will next be seen in ‘Jabariya Jodi’ along with actor Sidharth Malhotra. The film is scheduled for release on August 2. Directed by Prashant Singh, ‘Jabariya Jodi’ is based on ‘Pakadwa Vivah’ (forced marriage), which was once rampant in Bihar.