28 Nov 2016

Page 1

UIT LRC – B U L L E T I N

(Vol-01) 28.11.2016

HEADLINES TODAY 

மின்னணு

பரிமாற்றமம இலக்கு!: 

மமாடி ரயில்

பணப்

பிரதமர்

டிக்கெட்

முன்பதிவில்

திருநங்கெயர் மூன்றாம்

பாலினமாெ மேர்ப்பு 

உலகத்

தரத்துக்கு உயர்த்த

பள்ளிகள்

தர

மதிப்பீ டுத் திட்டம்

இன்கறய தினம்… 28.11.1820: ெம்யூனிே ேித்தாந்தத்கத உருவாக்ெியவர்ெளில் ஒருவரான பிகரட்ரிக் எங்கெல்ஸ்

பிறந்த நாள்

இன்று!

UIT LRC BULLETIN ARCHIVES Click Here Visit our library Web Portal http://uitcentrallibrary.wixsite.com/home

Make reading a habit and books your best friends of all time I always feel that blessed are those souls that love reading. After all, someone has rightly said, “Reading is to the mind what exercise is to the body”. Reading offers not one but several benefits. First of all, it is a good relaxant and absorbs stress and tension. It takes away boredom and introduces us to calmness; and, like music uplifts our mood and spirits. May be for the same reason Charles De Montesquieu once said, “I have never known any distress that an hour’s reading did not relieve.” It also holds huge power to change our mindset and this can directly enhance our personality. In other words, by making books our friends, we give ourselves an opportunity to broaden our minds just as travel does. It should also not be overlooked that having an open mind is very important as it will help in achieving success in life. Making books our best friends is one way of achieving it. Those who never give up reading remain alert as the mind is always active. They tend to be more creative and imaginative, which boosts the health of the brain. Many psychologists also believe that this protects the brain against many of the 1


UIT LRC – B U L L E T I N age-related ailments that are commonly seen in elderly people, like dementia, amnesia, etc. I feel when our brain becomes creative and imaginative it also becomes easier for us to discover our hidden talent and to take it to new heights. As is often said: “Logic will take you from A to B but imagination along with creative wings will take you everywhere.”

(Vol-01) 28.11.2016

Most importantly, by reading one also lives through different experiences of different authors and learns so many inspiring lessons that can be helpful in one’s life. Link | Hindustan November 2016

Times

|

24

CHENNAI TEAM TURNS LEATHER WASTE INTO CARBON FOR ELECTRODES

The collagen fibre was converted into carbon without oxidising the chromium Researchers at the Vellore Institute of Technology University, Chennai, have successfully converted leather solid waste (wet blue leather splits) containing chromium (III) into porous carbon matrix for use as electrodes in supercapacitors using a simple, sequential, two-step process. This approach not only yielded “excellent porous electrode material for supercapacitors”, but also effectively addressed the management of chromium-containing leather solid waste, which is considered to be the major issue of leather manufacturing industry. The results were published in the Journal of Hazardous Materials.

Chromium (Cr) is widely used in leather tanning as it imparts toughness to leather. Though Cr(III) present in leather waste is not toxic, it can undergo spontaneous oxidation and get oxidised into Cr(VI) which is toxic. The conventional disposal methods, such as land filling and incineration, cannot be considered as an ideal way of disposing the waste in an ecofriendly manner. “The prime constituent of leather is collagen fibre. So we thought of converting the collagen fibre into carbon fibre without oxidising the Cr(III) to Cr(VI),” says Dr. L. John Kennedy from the Physics Division - Materials, School of Advanced Sciences, VIT University, Chennai, and the corresponding author of the paper. As a first step, the leather waste was precarbonised by heating it for four hours at 400 degree C. The precarbonised material was soaked in potassium hydroxide overnight and then heated at higher temperature in an inert atmosphere to produce porous carbon that contains inter-connected nanopores of all three sizes — micropores (less than 2 nm), mesopores (2-50 nm) and macropores (over 50 nm). Since the carbon contains all the three types of pores, it is called hierarchical porous carbons (HPCs). Role of pores

2


UIT LRC – B U L L E T I N The pores of different sizes are formed by pore drilling and pore widening due to the combined effect of potassium hydroxide and temperature. In addition to pore formation, graphitic stable carbon structure is also formed. The chromium present in the leather induces graphitisation in the carbon material; the graphitic content present in the material improves its electrical conductivity property. “We are not only taking care of chromium disposal, the metal actually improves the property of the carbon,” he says. Hierarchical porous carbon is considered as a promising material for making electrodes that can be used in supercapacitor devices. Three types The three types of interconnected pores have very different roles in rendering the carbon a good electrode material. (While the micropores enhance the electrical double layer formation, the mesopores provide ion-transport pathways with low resistance, and the macropores serve

(Vol-01) 28.11.2016

as ion-buffering reservoirs to reduce the diffusion distance.) At 900 degree C, the specific capacitance value was 1960 Farad per gram using one molar of potassium chloride electrolyte; the specific capacitance value was less at lower temperatures. “The mesopore volume increases with increasing temperature and this leads to higher specific capacitance,” Dr. Kennedy says. As the hierarchical porous carbon is highly porous and has higher surface area, adequate ions diffuse into the inner pores of the electrode material. Since more ions are adsorbed on these electrodes compared to normal electrodes, the charge storage capacity becomes higher. “We have explored and proved the potential of converting hazardous leather waste to an excellent electrode material for energy storage device concept,” he says. THE HINDU-28.11.2016

3


Turn static files into dynamic content formats.

Create a flipbook
Issuu converts static files into: digital portfolios, online yearbooks, online catalogs, digital photo albums and more. Sign up and create your flipbook.