Graphene: The Supermaterial

In this atomic era of Nanotechnology and Quantum analysis, scientists Andre giem and konstantin Novoselov at University of Manchester in 2010 discovered the material, Graphene, which is only one atomic layer thick, for which they got the Nobel Prize (2010).

Graphene is allotrope of carbon which is even harder than diamond and hundred times stronger than Steel. This mono atomic layer is extremely durable, stable, conductive, strongest material ever tested in lab. The Nobel Prize announcement was done saying one meter graphene hammock would support a 4 kg cat but would only weight as much as one of cat’s whiskers( 0.77 mg).

In 2013, European Union invested 1 billion Euro for research purpose about possible applications of graphene along with other universities for a decade. The possible applications of graphene is immense including semiconductivity, photo electric circuits, tissue engineering ,optical modulation, biosensors, seawater filtration, waterproof coating, bulletproof outfits, aviation industries, electromagnetic fields for Nano Antennas and many more.

This material is supposed to be game changer in field of mechanical engineering. It is very thin, lightweight, strongest material which can replace old metallic sheets for metallic construction of machines making it lighter, stronger and efficient when used with carbon fibre. Moreover, the engines when coated with this material increases life of engine, efficiency and its various properties. In 2011, researchers found out that vertically aligned multilayer graphene structure can be an approach for graphene based thermal management of metallic machine parts. Graphene has peculiar property of responding to electromagnetic field which help in communication with Aero-vehicles through absorption and transmission of radio waves as nanoantennas .  Graphene when added to lanthanum and partly reduced titanium oxide produce strong seebeck effect at temperature ranging from room temperature to 750 degree Celsius which would convert 5% of heat into electricity. We can even filter sea water through it and fulfill demand of drinking water at different places.

It can be used as super capacitor which would claimed to achieve very high energy density comparable to lithium ion battery. This is great news for mechanical engineers who are working in the field of green energy vehicles. Recently, it has been used to build “an electric car” in India where graphene -based air- metal electrochemical cell is used which has increased range of electric cars from 100 kilometers to more than 500 kilometers . This electric cars actually runs by changing electrolyte (water) regularly and electrode (Aluminum) occasionally.

Fig: energy content of graphene based battery||(image source :/nanographene.net)

In a nutshell, this Graphene is wonder material which can improve engineering fields to a greater extent making the life of engineers easier and exciting. So, there would not be any hesitation to call graphene a ”SUPER MATERIAL”.

– Daya Bandhu ghimire

The Future is Electric

With the introduction of the 21st century, humans have started becoming more environment centric than ever and with it now the car makers, both legendary and the new ones are now in a race to electrify the automotive industry.

“One in Six Cars in the World will be electric by 2025.”, a survey by UBS Global Autos reports.

Introduction

Electric Vehicles or simply EVs are simply vehicles with one or more electric motor that is used for propulsion. With the advancements in battery technology from countries such as China and Japan, EV’s can now challenge vehicles with internal combustion engines in terms of range as well as performance, such that EV’s have now resurged from long absence and have started taking the market. The EV’s are categorized into a lot of types which includes hybrid cars which combines a combustion engine with an electric motor and battery to reduce fuel consumption and carbon footprints, plug-in hybrids that can be charged for short range travel in battery power alone and the combustion engine kicks in when battery reaches end of range or on driver’s demand, battery electric cars that runs completely on batteries producing zero emissions. Also, as an alternative, tests have already begun for fuel cell vehicles which uses hydrogen gas to power an electric motor which virtually has no emissions if hydrogen comes from renewable sources. And also for the terrains like that of our country, plug-in hybrids are the suitable ones as charge stations are distant and battery power alone is not reliable enough.

The Future is Electric (and Clean)

Electric vehicles will one day push fuel powered ones out of the automotive business map -but how soon? Sooner than we might think, according to reports from the International Monetary Fund, by 2040 more than 90% of all passenger vehicles in the U.S., Canada, Europe and other rich countries could be electric. Along with a rush of recent commitments to electric vehicles by governments and car companies, the study offers hope about the prospects for ceasing the transportation sector off carbon. Of more than one billion registered vehicles on the road today, only two million are electric (with one million of those in China alone). But if EV’s catch on as fast as the researchers project, it could reduce oil use by 3.34 billion liters a day and cut CO2 emissions 3.2 billion tons a year.

Established car manufacturers like BMW and Daimler AG are spending billions in a race to gain market share in electric-car market, hoping their existing scale will help them leapfrog newer companies like Tesla that focus exclusively on electric vehicles. A policy in China makes electric-vehicle sales and production compulsory in coming future. According to analysts, by the middle of the next decade, global sales of electric vehicles should hit 16.5 million, a 16% increase from the previous estimate. They predict electric vehicles will make up 16% of all car sales by then, up from a previous estimate of 14%. “The shift to electric cars will come faster and in a more pronounced way, fueled by the diesel demise in Europe, battery technology advancements and regulation in China and Europe,” Patrick Hummel, the leading analyst said. Below are some of the electrified models that are making global impacts or are set to revolutionize the car industry.

Nissan Leaf, a compact five-door hatchback electric car manufactured by Nissan which was introduced in Japan in December 2010 is the bestselling electric production car in the world. Powered by a 30 kWh battery, with a 147hp motor and a class toping range is 172 km on a full battery charge, Leaf battery packs can be charged from fully discharged to 80% capacity in about 30 minutes using fast charging. More than 300,000 units have been sold worldwide till January 2018.

The BMW i8 is the ultimate evolution of plug-in hybrid technology, with an environmental conscience and a carbon fiber body promising sports car like performance. Having 2 electric motors and a 3-cylinder petrol engine producing a combined 357hp and a low weight carbon fiber body of 1567kgs, this car can give the world’s best sports car series, the Porsche 911 and BMW’s own M4 run for their money. That’s why more than 10000 units of this car have been sold despite having a high price tag of $150,000.

Tesla Roadster, a production ready supercar concept recently launched by the revolutionary Elon Musk have claimed the title of the world’s quickest car with an acceleration of 0-100kmph in just 1.9seconds. Having a range of almost 1000km per single charge, this supercar has a top speed of 400kmph, even Bugatti Chiron or Koenigsegg Agera RS  cannot defeat this roadster priced at just $250,000 that’s 10 almost 10 times less than the above mentioned hypercars. Even the hypercars have adopted the electric technology, then why can’t we!! 

-Siddhartha Shakya

Bird Strike Events and Incidents

Bird strikes are accidents occurring mostly in civil aircrafts that can lead to fatality and/or destruction of an aircraft as a result of collision with birds. The first known bird strike was recorded to be September 7, 1908 when Orville Wright was flying in Dayton, Ohio and was chasing birds. The first fatal accident was recorded in 1912 in at Long Beach, California, which killed Cal Rogers, the first person to fly across the USA. Although birds are small creatures as compared to large aircrafts, the accidents caused by bird strikes should be taken very seriously. This is because the bird strikes cause direct damage to wing structure and propeller.

But the majority of bird strikes (around 65%) cause little damage to the aircraft. From 1912 to 1995, bird strikes have caused 30 fatal accidents, the destruction of more than 52 civil aircrafts and 190 deaths. In the recent years, the International Civil Aviation Organization (ICAO) reports 65,139 bird strikes from 2011 to 2014. The Kathmandu Valley is the home of more than 500 varieties of birds. In addition, the Tribhuvan International Airport is at the center of the valley. The valley also has problems with solid waste management and dumping sites. The earthworms that dwell below the ground and die on the runway also attract a large number of birds to the airport. Also, the smell of food from nearby restaurants contributes to the large number of bird strikes in Kathmandu. There are also grains lying around Pashupati which is quite near the airport. Hence, there are many causes of bird strikes in Kathmandu in particular and the concerned authority should take concrete steps to reduce these risks.

-Purak Adhikari